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Developing strategies toward safe and effective drug delivery into the central nervous system (CNS) with improved targeting abilities and reduced off-target effects is crucial. CNS-targeted drug carriers made of synthetic molecules raise concerns about their biodegradation, clearance, immune responses, and neurotoxicity. Cell-derived nanovesicles (CDNs) have recently been applied in CNS-targeted drug delivery, because of their intrinsic stability, biocompatibility, inherent homing capability, and the ability to penetrate through biological barriers, including the blood-brain barrier. Among these CDNs, extracellular vesicles and exosomes are the most studied because their surface can be engineered and modified to cater to brain targeting. In this review, we focus on the application of CDNs in brain-targeted drug delivery to treat neurological diseases. We cover recently developed methods of exosome derivation and engineering, including exosome-like particles, hybrid exosomes, exosome-associated adeno-associated viruses, and envelope protein nanocages. Finally, we discuss the limitations and project the future development of the CDN-based brain-targeted delivery systems, and conclude that engineered CDNs hold great potential in the treatment of neurological diseases.

Objective To develop and validate a magnetic resonance imaging (MRI)-based machine learning classifier for evaluating the tumor-stroma ratio (TSR) in patients with pancreatic ductal adenocarcinoma (PDAC). Materials and Methods In this retrospective study, 148 patients with PDAC underwent an MR scan and surgical resection. We used hematoxylin and eosin to quantify the TSR. For each patient, we extracted 1,409 radiomics features and reduced them using the least absolute shrinkage and selection operator logistic regression algorithm. The extreme gradient boosting (XGBoost) classifier was developed using a training set comprising 110 consecutive patients, admitted between December 2016 and December 2017. The model was validated in 38 consecutive patients, admitted between January 2018 and April 2018. We determined the performance of the XGBoost classifier based on its discriminative ability, calibration, and clinical utility. Results A log-rank test revealed significantly longer survival in the TSR-low group. The prediction model displayed good discrimination in the training (area under the curve [AUC], 0.82) and validation set (AUC, 0.78). While the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for the training set were 77.14%, 75.00%, 0.76%, 0.84%, and 0.65%, respectively, those for the validation set were 58.33%, 92.86%, 0.71%, 0.93%, and 0.57%, respectively. Conclusion We developed an XGBoost classifier based on MRI radiomics features, a non-invasive prediction tool that can evaluate the TSR of patients with PDAC. Moreover, it will provide a basis for interstitial targeted therapy selection and monitoring.

Objectives We aimed to develop and validate a multimodality radiomics model for the preoperative prediction of nonfunctional pancreatic neuroendocrine tumor (NF-pNET) grade (G). Methods This retrospective study assessed 123 patients with surgically resected, pathologically confirmed NF-pNETs who underwent multidetector computed tomography and MRI scans between December 2012 and May 2020. Radiomic features were extracted from multidetector computed tomography and MRI. Wilcoxon rank-sum test and Max-Relevance and Min-Redundancy tests were used to select the features. The linear discriminative analysis (LDA) was used to construct the four models including a clinical model, MRI radiomics model, computed tomography radiomics model, and mixed radiomics model. The performance of the models was assessed using a training cohort (82 patients) and a validation cohort (41 patients), and decision curve analysis was applied for clinical use. Results We successfully constructed 4 models to predict the tumor grade of NF- pNETs. Model 4 combined 6 features of T2-weighted imaging radiomics features and 1 arterial-phase computed tomography radiomics feature, and showed better discrimination in the training cohort (AUC = 0.92) and validation cohort (AUC = 0.85) relative to the other models. In the decision curves, if the threshold probability was 0.07–0.87, the use of the radiomics score to distinguish NF-pNET G1 and G2/3 offered more benefit than did the use of a “treat all patients” or a “treat none” scheme in the training cohort of the MRI radiomics model. Conclusion The LDA classifier combining multimodality images may be a valuable noninvasive tool for distinguishing NF-pNET grades and avoid unnecessary surgery.

Purpose To evaluate the diagnostic performance of the delayed-phase difference between tumor and pancreas for differentiating solid pseudopapillary tumors (SPTs) from non-functional neuroendocrine tumors (NF-NETs) of the pancreas. Methods This retrospective review included 148 consecutive patients with SPT and 98 consecutive patients with NF-NET confirmed by pathology. Patients with SPT and NF-NET were matched via propensity score matching (PSM). All patients underwent multidetector computed tomography (MDCT). For each patient, the delayed-phase difference between the tumor and pancreas was measured, and the performance of this variable was assessed based on its discriminative ability and clinical utility. Results After PSM, 27 patients with SPT and 27 patients with NF-NET were included in the matched analysis. There were no statistically significant differences in clinical and CT characteristics between the resulting two groups (p > 0.05). The delayed-phase difference values between the tumor and pancreas were significantly lower in patients with SPT (median: -0.45; range: -2.05 to 0.73) than in patients with NF-NET (median: 0.71; range: -1.39 to 2.38). The delayed-phase difference between tumor and pancreas had a high diagnostic accuracy (area under the curve=0.88). The best cutoff point based on maximizing the sum of the sensitivity and specificity was -0.23 (sensitivity = 88.89%; specificity = 88.89%; accuracy = 0.89). Conclusions The delayed-phase difference between tumor and pancreas can accurately and noninvasively differentiate SPT from NF-NET.

Chromatin regulators (CRs) regulate the gene transcription process through combinatorial patterns, which currently remain obscure for pan-cancer. This study identified the interaction of CRs and constructed CR-CR interaction networks across five tumor cell lines. The global interaction analysis revealed that CRs tend to function in synergistically. In addition, common and specific CRs in interaction networks were identified, and the epigenetic processes of these CRs in regulating gene transcription were analyzed. Common CRs have conserved binding sites but cooperate with different partners in multiple tumor cell lines. They also participate in gene transcription regulation, through mediation of different histone modifications (HMs). Specific CRs, ATF2 and PRDM10 were found to distinguish liver cancer samples with different prognosis. PRDM10 participates in gene transcription regulation, by exertion of influence on the DNA methylation level of liver cancer. Through analysis of the edges in the CR-CR interaction networks, it was found EP300-TAF1 has genome-wide distinct signaling patterns, which exhibit different effects on downstream targets. This analysis provides novel insights for the understanding of synergistic mechanism of CRs function, as controllers of gene transcription across cancer types.

We report an investigation into the impact of applying a large reverse bias voltage during current–voltage (J-V) sweeps on the degradation rate of solar cells based on poly[N-9″-hepta-decanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT) and [6-6]-phenyl C71-butyric acid methyl ester (PC70BM), under air mass 1.5 simulated solar irradiation. The degradation rate was found to be significantly slower when devices were characterized using frequent J-V sweeps with a large reverse bias component (-7 V to 1 V), with a decrease in power conversion efficiency of 24% after ∼ 100 hrs of light exposure. In contrast, devices scanned from −1 V to 1 V degrade by 72% in the same time period. The decay in the photovoltaic performance was found to be related to an increase in the series resistance and a decrease in the shunt resistance of the devices over time. Further characterization of the bulk heterojunction layer under irradiation conditions indicates that this behavior might be caused by the decreasing mobility of the charge carriers due to the formation of the defects or traps in the layer, induced by the photo-oxidation process. The frequent application of a large reverse bias sweep most likely helps de-trap the charge carriers and slows down the device degradation. Impedance analysis indicated that during the decay of PCDTBT:PC70BM devices the bulk layer became more resistive with time, and applying large and frequent reverse bias sweeps during testing could significantly slow down this process. The charge carrier extraction time was found to increase from 7 μs to more than 400 μs after photo-degradation. These findings demonstrate that repeated application of a reverse bias voltage can affect device degradation, and therefore that the specific details of J-V characterization should be reported alongside device lifetime claims.

Rationale and Objective To investigate the significance of magnetic resonance imaging (MRI)-based radiomics model in differentiating local recurrence of rectal cancer from nonrecurrence lesions at the site of anastomosis. Materials and Methods A total of 80 patients with clinically suspected lesions of anastomosis underwent 3.0T pelvic MRI consisting of T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and contrast-enhanced T1-weighted volume interpolated body examination (VIBE) imaging. Radiomics features were extracted from volumes of interest (VOIs), delineated manually on multiple MRI sequences. Subsequently, principal component analysis reduced the dimensionality of features for T2WI, DWI, VIBE, and combined multisequences, respectively. On this basis, the extreme gradient boosting (XGBoost) classifier was trained to build ModelT2WI, ModelDWI, ModelVIBE, and Modelcombination. Receiver operating characteristic curves were generated to determine the diagnostic performance of various models. Results Principal component analysis selected eight, four, seven, and six principal components to construct the radiomics model for T2WI, DWI, VIBE, and combined multisequences, respectively. Modelcombination had an area under the receiver operating characteristic curve of 0.864, with sensitivity and specificity of 81.82% and 75.86% in the validation set, demonstrating a more optimal performance compared to other models (p Conclusion This study demonstrated that MRI-based radiomics is a sophisticated and noninvasive tool for accurately distinguishing LR from nonrecurrence lesions at the site of anastomosis. Combining multiple sequences significantly improves its performance.

To investigate the exact relationship between CT tumor size and the microscopic tumor size in PDAC.We enrolled 310 patients with pathologically confirmed PDAC without preoperative adjuvant therapies who underwent CT examination from June 2016 and December 2018. Smooth curve fitting and a segmented regression model were used to analyze the threshold effect between CT tumor size and the microscopic tumor size.The tumor size was 2.93±1.15 cm under the microscope and 3.00±1.23 cm in CT. The mean bias was 0.067 cm between CT and microscopic assessments. The accuracy of CT T stages was 61.02% (36/59), 79.41% (162/204) and 57.45% (27/47) in T1, T2 and T3, respectively. A non-linear relationship was detected between CT tumor size and the microscopic tumor size, with a turning point of 4.3 cm. On the left of the inflection point, the effect size, 95% confidence interval, and p value were 0.51, 0.40 to 0.63, and0.0001, respectively. However, we observed no relationship between CT size and microscopic tumor size on the right of the inflection point (0.22, 0 to 0.44, 0.053).The relationship between CT and the microscopic tumor size is non-linear. When the CT tumor size was4.3 cm, every 1-cm increase in CT tumor size was associated with a 0.56 cm increase in microscopic tumor size. When the CT tumor size was4.3 cm, every 1-cm increase in CT tumor size was associated with a 0.91 cm increase in microscopic tumor size.

The present work aimed to develop and validate a radiomics model for evaluating peritoneal cancer index (PCI) in peritoneal metastasis (PM) cases based on preoperative CT scans.Pathologically confirmed pancreatic, colon, rectal, and gastric cancer cases with PM administered exploratory laparotomy in 2 different cohorts were retrospectively analyzed. Surgical PCIs (sPCIs) were confirmed by the surgery team, and CT-PCI scores were assessed by radiologists. Totally 63 and 27 cases in cohort 1 were assigned to the training and test groups, respectively. Then, 73 cases in cohort 2 were enrolled as an external validation set. Radiomics features were derived from the portal venous phase of preoperative abdominopelvic CT scans. Nineteen optimal features related to sPCI were finally selected. Support vector machine (SVM) was adopted for radiomics model generation. The associations of CT-PCI, radiomics PCI and sPCI were analyzed. The performances in distinguishing between low-sPCI (≤ 20) and high-sPCI (20) cases were also assessed by receiver operating characteristic (ROC) curve analysis and decision curve analysis (DCA).Both CT-PCI and radiomics PCI scores had positive associations with sPCI. The radiomics approach had higher agreement for detecting sPCI than CT-PCI. In addition, the radiomics model had enhanced diagnostic performance than CT-PCI (AUCs were 0.894, 0.822 and 0.810 in training, test and validation sets, respectively, vs 0.749, 0.678 and 0.693, respectively). The net reclassification index was 0.266. The usefulness of the proposed model was confirmed by DCA in an external validation set.The present pilot study showed that the radiomics model based on preoperative abdominopelvic CT has increased agreement and diagnostic performance in detecting sPCI than CT-PCI in patients with PM, which could be used to optimize individualized treatment strategies.

Background Childhood trauma is associated with major depressive disorder (MDD) and bipolar disorder (BD) in adults. However, no meta-analysis was performed on the prevalence of different types of childhood trauma in adults with affective disorders, using the Childhood Trauma Questionnaire (CTQ). Methods Four databases were used to search articles regarding the prevalence of childhood emotional abuse (CEA), childhood physical abuse (CPA), childhood sexual abuse (CSA), childhood physical neglect (CPN), and childhood emotional neglect (CEN) in patients with MDD and BD using the CTQ. Results A total of 17 and 11 articles were found analyzing patients with MDD and BD, respectively. A pooled prevalence rate of 33.0% and 30.0% for CEA, 17.0% and 18.0% for CPA, 19.0% and 22.0% for CSA, 37.0% and 31.0% for CEN, and 31% and 30.0% for CPN was found in patients with MDD and BD respectively. A difference in 95% confidence interval in the CSA rate between men and women was found in patients with MDD in the gender subgroup and in the rate of some types of childhood trauma in the continent subgroup in both patient types. Limitations A limited number of articles were included in some continents, thus, the heterogeneity in the meta-analysis was generally high. Conclusion The prevalence of CEA, CEN, and CPN in patients with affective disorders was relatively high, whereas that of CPA and CSA was relatively low. These childhood traumas might be affected by continent and gender.

Rationale and Objectives: A linear array of carbon nanotube-enabled x-ray sources allows for stationary digital breast tomosynthesis (sDBT), during which projection views are collected without the need to move the x-ray tube. This work presents our initial clinical experience with a first-generation sDBT device. Materials and Methods: Following informed consent, women with a “suspicious abnormality” (Breast Imaging Reporting and Data System 4), discovered by digital mammography and awaiting biopsy, were also imaged by the first generation sDBT. Four radiologists participated in this paired-image study, completing questionnaires while interpreting the mammograms and sDBT image stacks. Areas under the receiver operating characteristic curve were used to measure reader performance (likelihood of correctly identifying malignancy based on pathology as ground truth), while a multivariate analysis assessed preference, as readers compared one modality to the next when interpreting diagnostically important image features. Results: Findings from 43 women were available for analysis, in whom 12 cases of malignancy were identified by pathology. The mean areas under the receiver operating characteristic curve was significantly higher (p < 0.05) for sDBT than mammography for all breast density categories and breast thicknesses. Additionally, readers preferred sDBT over mammography when evaluating mass margins and shape, architectural distortion, and asymmetry, but preferred mammography when characterizing microcalcifications. Conclusion: Readers preferred sDBT over mammography when interpreting soft-tissue breast features and were diagnostically more accurate using images generated by sDBT in a Breast Imaging Reporting and Data System 4 population. However, the findings also demonstrated the need to improve microcalcification conspicuity, which is guiding both technological and image-processing design changes in future sDBT devices.

Magnaporthe oryzae infects rice, wheat and other grass crops through appressoria. The formation of the appressorium is regulated by the external environment, signal transduction pathways, and transcription factors. Transcription factors Vrf1 and Hox7 are involved in the regulation of appressorium formation. In this study, we demonstrate that Vrf1 and Hox7 play vital roles in coordinately regulating appressorium maturation. In strain 70-15, deletion of VRF1 resulted in the inability to continue melanization and maturation of the incipient appressorium, and deletion of HOX7 also resulted in defects in appressorium melanization and maturation. The defects in appressorium formation in Δhox7Δvrf1 were similar to those in Δhox7 and Δvrf1. The gene expression profiles of the incipient appressoria at 5 h post-inoculation (hpi) showed that the expression levels of 704 genes (25.94 % of all differentially expressed genes in the three mutants) were significantly downregulated (606 genes) or upregulated (98 genes). In the appressoria of Δhox7, Δvrf1, and Δhox7Δvrf1 at 5 hpi, the expression level of genes related to cell wall remodeling was changed. Genes for melanin synthesis, chitin and glucan degradation, and extracellular cell wall degrading enzyme were significantly downregulated, while genes for chitin and glucan synthesis were upregulated. After 8 hpi, the incipient appressoria of Δhox7, Δvrf1, and Δhox7Δvrf1 regerminated and formed swollen hyphal-like structures with multiple nuclei. The ratio of the nuclear number of the hyphal-like structures of Δhox7, Δhox7Δvrf1, and Δvrf1 was close to 6:4:2 at 24 hpi. Therefore, although Vrf1 and Hox7 are somewhat functionally different, they synergistically regulate appressorium maturation in M. oryzae.

To investigate the prevalence of attention deficit hyperactivity disorder (ADHD) among medical college students in a Chinese population.A cross-sectional design was used to collect demographic data on participants and their symptoms of ADHD, anxiety, and depression. Data were collected through questionnaires filled out on a computer or through WeChat, a widely used social media app.The prevalence of ADHD among 5693 college students was 3.5% (3.02∼3.98%). Individuals with ADHD showed higher scores on scales of anxiety and depression symptoms (both p 0.05) than the general population. There was a significant difference in the prevalence of ADHD grouped by smoking, drinking, suicidal ideation, suicidal plans, suicidal attempt, anxiety and depression (p 0.05). The odds ratio (OR) of ADHD was high for suicidal ideation, suicide plans, suicide attempts, anxiety and depression, with ORs of 5.901, 5.46, 6.011, 8.037 and 7.88, respectively. The ORs of suicidal behaviors for ADHD were decreased after adjusting for covariates such as drinking, smoking and depression.The sample was exclusively selected from three medical-related colleges, which might not be best representation of college students in China. Furthermore, majority of the participants were females.ADHD remains a common disorder among Chinese medical college students and is significantly associated with suicidal behaviors, anxiety and depression. It is important to increase awareness and promote effective interventions to this particular population.

The development of printable and air-stable unipolar n-type semiconductors remains a critical issue in the field of organic electronics in view of n-type transistors being indispensable components in the manufacture of low-power-consumption complementary (CMOS type) integrated circuits. In this work, we report on two dicyanomethylene-substituted diketopyrrolopyrrole derivatives with different alkyl side chains (DCM-DPP-C13 and DCM-DPP-C16) for n-type transistors. Compared with DCM-DPP-C16, the side chain branching point in DCM-DPP-C13 was moved further away from the conjugated backbone. Both materials showed promising electron mobility above 0.1 cm2/VS in air with remarkably low threshold voltages (−3 V – 2 V) on spin-coated bottom-contact bottom-gated devices on silicon substrates. Contrary to our original expectation, the average electron mobility of DCM-DPP-C16 (0.2 cm2/VS) was higher than that of DCM-DPP-C13 (0.12 cm2/VS) due to the bigger crystalline domains in the thin film of the former compound. We investigated the inkjet printability of these two compounds as well, and bottom-contact top-gated transistors were successfully fabricated on flexible PET substrates. Widely used Cytop was employed as the gate dielectric. Ag gate electrodes were readily inkjet printed on the gate dielectric by using a thin layer of Nafion as an adhesion promoter. DCM-DPP-C16 demonstrated an excellent inkjet-ability with good uniformity and reproducibility. An average electron mobility around 0.1 cm2/VS was achieved in air. This is an important step toward the fabrication of large-area organic CMOS logic circuits with low cost.

To evaluate the potential clinical value of Arterial spin-labeled (ASL) through comparison with computed tomography perfusion (CTP) in patients with chronic intracranial artery (middle cerebral artery, MCA) stenosis.Twenty-nine patients (14 female, average ages 62) were included in our study from October 2013 to August 2016. Relative cerebral blood flow (rCBF) in the MCA territory was calculated on both ASL and CTP. Patients were divided into three groups (mild, moderate and severe) based on their degree of MCA stenosis on DSA. The paired t-tests and Bland-Altman plots were used to evaluate the differences of rCBF between ASL and CTP.There was a significant difference in rCBF between ASL and CTP for all patients (P 0.001) and for those with severe MCA stenosis (P 0.001). For patients with mild or moderate stenosis, there were no significant differences (P = 0.496 and 0.645, respectively). The 95% limits of agreement for all patients and those with severe stenosis were (-0.25, 0.41) and (-0.13, 0.56), respectively. For patients with mild or moderate stenosis, the values were (-0.21, 0.22) and (-0.20, 0.19).Compared with CTP, ASL tended to overestimate the perfusion deficit in patients with severe chronic MCA stenosis. However, ASL is noninvasive, repeatable method and can be a promising clinical diagnostic tool to evaluate patients with intracranial stenosis.

Background: Although, in gastric cancer (GC), the presence of CD8 T cells and programmed cell death ligand-1(PD-L1) were considered as an inflamed marker for immunotherapy, the objective response rate was only 22% for this kind of patients. Herein, we comprehensively elucidate the gene mutation and expression, and functional enrichment pathways profile basing on CD8 and PD-L1 levels to better understand the immune pattern of inflamed GC and to interpretation the potential clinical treatment strategies to circumvent the obstacle of immunotherapy resistance for patients with different CD8 and PD-L1 levels. Methods: Histopathologic analysis was used to evaluate PD-L1/ CD8 expression in 186 tumor tissues from GC patients whose survival outcomes were recorded as well. Meanwhile, the gene expression and mutations of 289 GC samples in the Cancer Genome Atlas (TCGA) were computed using R 3.6.1 packages. Findings: The CD8/PD-L1 subtype were established with Types I (60.3%), II (11.8%), III (0%), and IV (27.9%) in 186 GC samples with survival outcomes related to CD8 T cells level. In 289 GC samples data from TCGA, all four CD8/PD-L1 subtypes had distinguishing molecular subtype with oncogenes and DNA damage repair-related (DDR) genes frequently altered in Type I, while TP53 mutations tend to be enriched in Type II and IV. Interpretation: We attempted to present a framework for distinguishing and conceptualizing the different signatures among GC with varied PD-L1/CD8 levels rely on histopathological data, gene mutation and expression to provide a new insight into the possibility of overcoming resistance of PD-1/PD-L1 inhibitors. Funding Statement: The work was supported by in part by Natural Science Foundation of Fujian Province (Grant No. 2017J01259, 2018J01267), Fujian provincial health and family planning research talent training program (Grant No. 2018-ZQN-13,2019-CX-4), Science and Technology Program of Fujian Province, China (Grant No. 2018Y2003, 2019L3018 and 2019YZ016006), Joint Funds for the innovation of science and Technology, Fujian province (Grant No. 2017Y9077，2018Y2003 and 2019YZ016006), Startup Fund for science research, Fujian Medical University (Grant No. 2019QH1196), and the National Clinical Key Specialty Construction Program. Declaration of Interests: None declared. Ethics Approval Statement: This study had been informed and approved by the ethics committee of the Fujian Medical University Cancer Hospital. All procedures in the study were conducted conformed to the standards set by the Declaration of Helsinki.

The paper presents a systematic description about the observation scheme analysis and practical observation of artificially triggered lightning with a ground-based microwave radiometer together with other discharging observation instruments at Guangzhou Field Experiment Site for Lightning research and testing in Conghua, Guangdong in the thunderstorm season of the 4 consecutive years from 2016 to 2019. The results from statistical analysis of the brightness temperature data observed from 2017 to 2019 show that: (1) The frequencies such as 28, 30, 51.25 and 51.76 GHz in atmospheric window are more likely to respond with outstanding brightness temperature pulses than other observation frequencies of the radiometer; (2) When the elevation angle is 30°, the observation distance is relatively short (99 m in this study), and the “lightning observation mode” is adopted, the efficiency for a ground-based microwave radiometer to capture the lightning heating effect caused by artificially triggered lightning can be improved; (3) The observation efficiency of the 3 years as a whole is 71.4% but gradually increases year by year; (4) The radiometer observation data can be used to reveal the characteristics of lightning heating effects such as duration and lightning current integral; (5) Combined with the lightning current data measured by a coaxial shunt during the experiment, it was found that the estimated lightning heating effect durations based on 25 artificially triggered lightning observations are well consistent with the lightning current durations, as shown by the correlation coefficient of 0.73. This also implies that the radiometer working on the lightning observation mode presented by this paper can observe the lightning heating effect and estimate its duration.

Indigenous microbial consortia are closely associated with soil inherent components including nutrients and minerals. Although indigenous microbial consortia present great prospects for bioremediation of vanadate [V(V)] contaminated soil, influences of some key components, such as available phosphorus (AP), on V(V) biodetoxification are poorly understood. In this study, surface soils sampled from five representative vanadium smelter sites were employed as inocula without pretreatment. V(V) removal efficiency ranged from 81.7 ± 1.4% to 99.5 ± 0.2% in batch experiment, and the maximum V(V) removal rates were positively correlated with AP contents. Long-term V(V) removal was achieved under fluctuant hydrodynamic and hydrochemical conditions in column experiment. Geobacter and Bacillus, which were found in both original soils and bioreactors, catalytically reduced V(V) to insoluble tetravalent vanadium. Phosphate-solubilizing bacterium affiliated to Gemmatimonadaceae were also identified abundantly. Microbial functional characterization indicated the enrichment of phosphate ABC transporter, which could accelerate V(V) transfer into intercellular space for efficient reduction due to the structural similarity of V(V) and phosphate. This study reveals the critical role of AP in microbial V(V) decontamination and provides promising strategy for in situ bioremediation of V(V) polluted soil.

Automatic image segmentation is an indispensable step in medical image analysis, and it plays an important role in computer-assisted radiotherapy, disease diagnosis and treatment effect evaluation. The difficulty of medical image segmentation is greatly enhanced by the blurry nature of medical image, the complex shape of objects and the existence of noise. In recent years, segmentation methods based on deep learning, especially convolutional neural network, have made great progress in improving the accuracy of medical image segmentation. However, these methods also have poor ability to distinguish similar objects in different environments, because of insufficient use of the local context information of images during the process of feature extraction. To address this problem, this paper proposes a deep neural network (LCP-Net) that can perceive multi-scale context information of images. LCP-Net improves the utilization of context information of feature encoders by using Parallel Dilated Convolution (PDC) and Local Context Embedding (LCE), which are beneficial to get feature map rich in environmental information. In addition, to improve the segmentation accuracy of the model for small objects and alleviate the swing issue during training, we propose a novel improved cross-entropy loss (DDCLoss), which can adaptively adjust the weight of loss according to the certainty and deviation distance of the predicted pixel value and enable the model to focus on optimizing the sample points with low certainty and tend to be mislabeled. Experimental results on three different medical datasets demonstrate that compared with the state-of-the-art medical image segmentation models, our proposed LCP-Net can achieve better segmentation performance.

Extranodal NK/T-cell lymphoma (ENKTL), nasal type is an aggressive lymphoma characterized by rapid clinical progression, an unfavorable prognosis, and a short survival time. This study aimed to investigate the correlations of c-MYC protein expression, gene rearrangement, and gene copy number with the prognosis of ENKTL. Immunohistochemistry for CD20, CD3, CD56, TIA-1, Ki-67, and c-MYC were performed using tissue sections from 68 patients diagnosed with ENKTL. In situ hybridization was performed to detect Epstein-Barr virus (EBV)-encoded small RNA (EBER). c-MYC genetic alterations (located on chromosome 8q24) were detected using fluorescence in situ hybridization. Sixty patients with nasopharyngeal mucosa lymphadenosis were selected as a normal control group for the c-MYC gene and protein. Immunophenotypically, CD3 and TIA-1 were positive in all patients, CD56 was positive in 54 patients (79.4%), and CD20 was negative in all patients. A Ki-67 proliferation index of > 50% was observed in 94.1% of patients (64/68). In situ hybridization for EBER was positive in all patients. The c-MYC positive expression rate (> 40% of tumor cells with nuclear staining regarded as positive) in patients with ENKTL was 50% (34/68), which was significantly higher than that in patients with nasopharyngeal mucosa lymphadenosis (0%, 0/60; p 0.05). Multivariate Cox regression analysis further confirmed that clinical stage and c-MYC positivity were independent prognostic factors in patients with ENKTL. The abnormal expression of c-MYC may play an important role in the development and progression of ENKTL and influence the prognosis of patients.

Mackinawite (FeS), a widely-distributed natural reducing mineral, can donate electron for various (bio)processes. However, little is known about mackinawite-driven chemoautotrophic bioreduction of toxic vanadate [V(V)] in aquifer. This study demonstrates that V(V) is successfully bioreduced by mackinawite under anaerobic condition via 150-d operation of constructed aquifer. Complete V(V) removal was achieved at the initial concentration of 10 mg/L and flow rate of 0.125 mL/min. Fluctuant hydrochemistry and hydrodynamics affected V(V) removal performance. Biotic activity was identified as the major contribution to V(V) transformation (76.4 ± 1.01%). Chemoautotrophic genera (e.g., Thiobacillus) could oxidize FeS coupled to direct V(V) reduction independently. Heterotrophic V(V) reducers (e.g., Pseudomonas and Spirochaeta) could also achieve V(V) detoxification by utilizing metabolic intermediates synthesized by autotrophic Fe(II) oxidizers (e.g., Thiobacillus) and S(-II) oxidizing genera (e.g., Sulfuricurvum). Gene abundance and enzymatic activity tests confirmed that nitrate reductase gene napA functioned crucially in chemoautotrophic V(V) reduction by Fe(II) and S(-II) donating electron. V(V) was reduced to insoluble V(IV) while elements in mackinawite were oxidized to Fe(III) and SO42−. This study reveals the coupling of iron, sulfur and vanadium in biogeochemical cycling, and offers a promising strategy for remediation of V(V)-polluted aquifer.

The synthesis of 4,4ʹ-difluoro-2,2ʹ-bithiophene is reported and an alternating donor-acceptor copolymer of this moiety and diketopyrrolopyrrole has been prepared. This polymer has a lower highest occupied molecular orbital than its non-fluorinated analogue polymer. Organic thin film transistors based on this polymer showed p-type charge transport behavior and a hole mobility of 0.21 cm2 V−1 s−1 in bottom-gate bottom-contact devices. Organic solar cells using this polymer as donor and [6,6]-Phenyl-C71-butyric acid methyl ester as acceptor achieved a power conversion efficiency of 3.4% with a high fill factor of 69%. Our morphology analysis showed that there was a lack of long-range ordered structure in the neat polymer thin film, which could cause the inferior device performance.

Introduction Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide. The search for new biomarkers that predict the outcome of HCC patients is ongoing. We propose the second harmonic generation–based quantitative assessment approach to evaluate the prognostic value of tumor stromal collagen in HCC. Materials and methods We evaluated tumor stromal collagen in paraffin-embedded specimens from 109 HCC patients by second-harmonic generation imaging. The parameters and quantitative assessment of collagen were obtained using a fiber network extraction algorithm. The relationships between collagen features and clinical pathological features and overall survival were statistically analyzed. Result Among the collagen features, some parameters of aggregated collagen correlated well with clinical pathological features, especially the aggregated collagen cross-linked density. Cross-linked collagen fibers form a fiber network in moderately and poor differentiated HCCs. Kaplan–Meier analyses and the multivariate Cox proportional hazard model showed that high aggregated collagen cross-linked density was associated with poor overall survival. The chi-squared test showed that aggregated cross-link density was significantly associated with histological grade and tumor recurrence. Conclusion Our results indicate the prognostic value of the quantitative evaluation of tumor stromal collagen using second harmonic generation imaging of patients with HCC.

We report on inkjet printable gate-dielectric based on a spin-on-glass (SOG) material for applications in n-type organic field-effect transistors (OFETs). The SOG material is polymethylsilsesquioxane in alcohol mixture. After annealed at 135 °C in air, the SOG films are well crosslinked and have a good resistance against alcohol, which allows for the inkjet printing of Ag gate electrodes on top of the SOG dielectric. The crosslinked SOG films are very dense, and can withstand high electric field. This is very beneficial to the operation of transistors. In addition, the SOG films have very low hydroxyl content after annealing. This property is very important for n-type transistors. After ink formulation, this SOG dielectric has an excellent inkjet-ability with good uniformity and reproducibility. By using Polyera's P(NDI2OD-T2) as the semiconductor and SOG as the dielectric, bottom-contact top-gated n-type transistors were successfully fabricated on PET substrates with electron mobility above 0.1 cm2/V and high on/off ratio well above 105. These remarkable results demonstrate that this newly formulated SOG dielectric is a promising candidate for the future development of flexible electronic devices.

Vanadium and chromium co-exist commonly with elevated levels in groundwater at vanadium smelting sites. While bioremediation has been recognized promising for this co-contamination treatment in aquifer, interactions during vanadium (V) [V(V)] and chromium (VI) [Cr(VI)] bio-reductions under autotrophic condition remain largely unknown. In this study, efficient reductions of V(V) and Cr(VI) from synthetic groundwater were realized simultaneously in a continuous flow autotrophic sulfur-based biosystem, with more than 85% overall removals under hydrochemical and hydrodynamic fluctuations during 276-d operation. Soluble Cr(VI) was reduced to insoluble Cr(III) preferentially, while reduction of soluble V(V) to insoluble V(IV) was easily inhibited. Elemental sulfur [S(0)] was bio-oxidized to sulfate. Analyses of carbon isotope, microbial community and metabolic pathway revealed the synergetic mechanisms. Autotrophs (e.g., Sulfuricurvum) utilized energy released from S(0) oxidation to synthesize volatile fatty acids (VFAs), which were consumed by heterotrophic V(V) and/or Cr(VI) reducers (e.g., Geobacter). Functional genes responsible for S(0) oxidation and reduction of V(V) and Cr(VI) were detected. V(V) and Cr(VI) reductions were catalyzed by both cytochrome c and nicotinamide adenine dinucleotide. VFAs were also transformed to glycogen in cells to store energy. Robust remediation strategy is thereby proposed for aquifer co-contaminated by V(V) and Cr(VI).

Background Tuned aperture computed tomography (TACT) and intraoral tomosynthesis were studied in the past and demonstrated improved detection of various dental diseases. However, interest in TACT waned because the technology was not viable for clinical use. Recently, interest resurged with the advent of the carbon nanotube field emission x-ray source array technology. Researchers from the University of North Carolina (UNC) Department of Physics and Astronomy and the UNC School of Dentistry designed, patented, and conducted several benchtop studies to demonstrate its utility.1 Objective The aim of this study was to develop a viable stationary intraoral tomosynthesis imaging device for clinical use. Materials and Methods XinVivo, an imaging device startup company, developed a prototype system designed for intraoral imaging applications.2 Results The prototype met all the requirements for clinical use and met the U.S. Food and Drug Administration (FDA) requirements for intraoral imaging devices. Discussion The clinical prototype met all manufacturer specifications. Preliminary studies indicated that stationary intraoral tomosynthesis (s-IOT) provides increased image quality and feature conspicuity at a dose comparable with that in a single 2-dimensional (2-D) intraoral radiography.3

AIM To find potential predictors at unenhanced computed tomography (CT) to evaluate the stone clearance rate (SCR) of pancreatic duct stones (PDS) by extracorporeal shock wave lithotripsy (ESWL). MATERIALS AND METHODS A total of 106 consecutive patients with multiple stones of maximal transverse length (MTL) 0.3–3.6 cm in pancreatic head region were enrolled. Unenhanced CT was performed both before and after ESWL therapy. All patients underwent ESWL therapy using an electromagnetic lithotripter, and were divided into three groups with threshold values of >90%, 50–90% and RESULTS The only significant predictor of SCR by ESWL was MSD (p CONCLUSION MSD on pre-treatment unenhanced CT is an independent predictor for SCR of PDS patients treated with ESWL. Using a cut-off value of 375.4 HU, patients with low MSD are good candidates for ESWL therapy.

The impact of uniaxial strain along the [111] direction on the structural and electronic properties of bulk HgTe in the zinc blende is studied by DFT. Uniaxial strain can effectively manipulate the local lattice structure along the same direction. The transformation may be caused to form the graphite-like structure in large compression and the layered one under stretching. Meanwhile, the conductive band minimum (CBM) and valence band maximum (VBM) are gradually shifted to form the indirect band structures. Further, the band gap is opened in HgTe for the significant stretching, The uniaxial compression only changes the coordination of HgTe by maintaining the semi-metallic properties.

Summary Background and purpose Intracranial large-artery atherosclerosis is considered a frequent cause of stroke worldwide, particularly in Asian populations. The current evidence suggests that symptomatic patients with severe stenosis may benefit from intracranial stents. There are two methods for calculating the degree of intracranial stenosis, Warfarin–Aspirin Symptomatic Intracranial Disease (WASID) and North American Symptomatic Carotid Endarterectomy Trial (NASCET), but they have never been compared. Methods A total of 25 patients with suspected middle cerebral artery (MCA) stenosis based on their acute presentation were imaged by computed tomography angiography (CTA), then confirmed by digital subtraction angiography (DSA). Measurements were carried out on symptomatic MCA using both methods for determining the degree of stenosis. Results The degree of stenosis was significantly different using NASCET and WASID methods in DSA (48.2% vs. 54.6%; P P = 0.9). All measurements were highly correlated between methods (Spearman r = 0.92 and 0.89, respectively; P Conclusion The results of this study suggest that NASCET and WASID measures are, on average, generally similar, although substantial disagreement in a given patient may be seen.

Polymer/inorganic-nanocrystals bulk heterojunction solar cells, where inorganic semiconductor nanocrystals such as CdSe, CdS, CdTe, ZnO, TiO 2 , and silicon, replace the fullerene molecules as the electron acceptors, typically exhibit a power conversion efficiency (PCE) below 3% even after tremendous engineering efforts to optimize the nanocrystal size, shape, and nanoscale morphology. One promising feature of polymer hybrid solar cells is the ability to sensitize conjugated polymers, which on their own absorb only in the visible part of solar spectrum, into the infrared spectral range using infrared-active lead salt nanocrystal quantum dots (NQDs). Here we observed for the first time hole transfer from PbS NQDs to polymers as evidenced by the quenching of the PbS photoluminescence (PL), a sign of the presence of charge separating type II heterojunction. The type II band-offset at the NQD/polymer heterojunction enables efficient hole extraction from NQDs and leads to a record PCE of 3.80%, realized in a planar junction configuration under simulated air mass 1.5 global (AM 1.5G) irradiation of 100 mW/cm 2 . The photocurrent has an extended spectral range spanning from the ultraviolet (UV) to the infrared (IR). Contributions from the polymer and PbS to the photocurrent were identified. Infrared photons (>700 nm) contribute about 30% of the photocurrent and yield a high external quantum efficiency (EQE) of 20% at 1050 nm.

In this work, two high boiling-point solvents (1-chloronaphthalene (CN) and 1,8-diiodooctane (DIO)) were utilized as co-additives in ortho-dichlorobenzene (ODCB) and chlorobenzene (CB) solutions to fine tune the donor and acceptor domains in the bulk heterojunction (BHJ) of poly(benzo[1,2-b:4,5-b′]dithiophene-alt-thieno[3,4-c]pyrrole-4,6-dione) (PBDTTPD) and fullerene derivatives. A power conversion efficiency of 7.1% and a fill factor up to 70% were obtained for solar cells with active area of 1 cm2 when using [6,6]-phenyl C61-butyric acid methyl ester (PC60BM) as acceptor, suggesting that an optimized morphology was achieved.

0.2PbNi 1/3 Nb 2/3 –0.8Pb(Zr,Ti)O 3 (PNN–PZT) thick films were deposited on Pt wire with the diameter of 50 μm by electrophoretic deposition (EPD) method. The EPD deposition times on the microstructures of PNN–PZT thick films were investigated. By optimizing the EPD process, the Pt wire can be uniformly wrapped with the PNN–PZT powders. During the sintering process, the as-deposited PNN–PZT/Pt wires were buried in the mixed powders of PbCO 3 and ZrO 2 , and then sintered in the optimal temperature to get a dense microstructure. The piezoelectric properties of the thick films were characterized by scanning force microscopy (SFM) method. The results show that the PNN–PZT thick films prepared by EPD method have good piezoelectricity.

Mesoporous aluminum-doped titanium dioxide (Al-TiO2) materials with high specific surface areas were prepared via a solid-state reaction route. The properties of these materials were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), energy dispersive spectroscopy (EDS), N2 absorption-desorption, ultraviolet visible light spectroscopy (UV-Vis) and electrochemical spectroscopy. The results show that the mesoporous structure of the product with ethanol is composed of anatase laced crystal walls with amorphous grain boundaries formed gradually by degradation. Compared with those without ethanol, these samples possess larger crystallite size since ethanol decreases the pore size at higher temperature. With the increase of ethanol amount, however, the crystallite size will grow. The amorphous grain boundaries in the mesoporous material, with a large impedance and low incidental cyclic potential, are difficult to effectively degrade and the phase transformation temperature is changed from 500 to 550 °C. The growth rate of Al-TiO2 crystallites that obeys the quadratic polynomial equation may be controlled.

Rationale and Objectives Challenges remain in the imaging of the lungs of free-breathing mice. Although computed tomographic (CT) imaging is near optimal from a contrast perspective, the rapid respiration rate, limited temporal resolution, and inflexible x-ray pulse control of most micro-CT scanners limit their utility in pulmonary imaging. Carbon nanotubes (CNTs) have permitted the development of field emission cathodes, with rapid switching and precise pulse control. The goal of this study was to explore the utility of a CNT-based micro-CT system for application in quantitative pulmonary imaging. Materials and Methods Twelve CB57/B6 mice were imaged during peak inspiration and end-exhalation using the CNT micro-CT system. The respiratory trace was derived from a sensor placed underneath the abdomen of the animal. Animals were allowed to breathe freely during the imaging under isoflurane anesthesia. Images were reconstructed using isotropic voxels of 77-μm resolution (50 kVp, 400 projections, 30-ms x-ray pulse). Lung volumes were measured with region-growing techniques and thresholds derived from the surrounding air and soft tissues. Basic functional parameters, including tidal volume, functional reserve capacity and minute volume, were also calculated. Results The average scan time was 13.4 ± 1.8 minutes for each phase of the respiratory cycle. Mean lung volumes at peak inspiration and end-expiration were 0.23 ± 0.026 and 0.11 ± 0.024 mL, respectively. The average minute volume was 11.93 ± 2.64 mL/min. Conclusions The results of this study demonstrate the utility of a CNT-based micro-CT system in acquiring prospectively gated images from free-breathing mice for obtaining physiologic data. This technique provides an alternative to breath-hold techniques requiring intubation and offers greater dose efficiency than retrospective gating techniques.

Effects of farmer field school (FFS) and the conventional (classroom lectures) training on acquisition of pest management knowledge and skills by small vegetable farmers were studied in Yunnan province, China from 2003 to 2007. There were significant gains of knowledge about vegetable pests, natural enemies, insect and disease ecology and pest management among the FFS farmers, but were no significant improvements of knowledge among the conventional trained farmers. Vegetable FFS enabled farmers to learn simple knowledge as well as complex IPM knowledge. In contrast, the conventional training only improved vegetable farmers' simple knowledge. The potential and limitations of FFS as a unique extension tool to disseminate the complex knowledge of IPM to smallholder farmers were demonstrated.

Amino tricyanovinyl thiophene chromophores (A-TCVT) are prepared by a substitution reaction of amino-phenylene vinylene thiophene (A-PVT) with tetracyanoethylene (TCNE). This reaction does not occur directly. The vinylene double bond in the PVT unit first reacts rapidly with TCNE to form a [2+2] cycloaddition product. It is then reverted to PVT unit prior to the subsequent substitution at 50 °C. This reversible cycloaddition converts the cis-isomer of PVT units into the trans-counterparts, thus the final TCNE substituted products can be expected for a better performance as non-linear optical materials.

A novel photovoltaic solar assisted heat pump (PV-SAHP) system has been proposed in this study. Performance tests with a range of condenser supply water temperature were conducted on an experimental rig. The dynamic performance of this PV-SAHP system in a 4-day period with very similar weather conditions was analyzed and the influencing factors were identified. The results indicate that this PV-SAHP system has a superior coefficient of performance (COP) than the conventional heat pump system and at the same time, the photovoltaic efficiency is also higher. The COP of the heat pump was able to reach 10.4 and the average value was about 5.4. The average photovoltaic efficiency was around 13.4%. The highest overall coefficient of performance (COPp/t), bringing into consideration both the photovoltaic and thermal efficiency, was about 16.1.