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A method to compute the resistance and capacitance parameters for driver's Thevenan equivalent circuit model was presented. Based on the minimum and maximum load capacitance, with two different output voltages chosen from the driver's output simulation curve, the output resistance and capacitance are derived according to the corresponding gate load delays. The results show that the driver's output curve plotted according to the calculated resistance and capacitance fits the Spice simulation curve well for output voltages chosen from 30%, 40%, or 50% of the final value. [ABSTRACT FROM AUTHOR]

The fabrication of van der Waals (vdWs) heterostructures mainly extends to two-dimensional (2D) materials. Nevertheless, the current processes for obtaining high-quality 2D films are mainly exfoliated from their bulk counterparts or by high-temperature chemical vapor deposition (CVD), which limits industrial production and is often accompanied by defects. Herein, we first fabricated the type-II p-PdSe 2 /n-InSe vdWs heterostructure using the ultra-high vacuum laser molecular beam epitaxy (LMBE) technique combined with the vertical 2D stacking strategy, which is reproducible and suitable for high-volume manufacturing. This work found that the introduction of 365 nm UV light illumination can significantly improve the electrical transport properties and NO 2 sensing performance of the PdSe 2 /InSe heterojunction-based device at room temperature (RT). The detailed studies confirm that the sensor based on the PdSe 2 /InSe heterojunction delivers the comparable sensitivity ( R a / R g = ∼2.6 at 10 ppm), a low limit of detection of 52 ppb, and excellent selectivity for NO 2 gas under UV light illumination, indicating great potential for NO 2 detection. Notably, the sensor possesses fast response and full recovery properties (275/1078 s) compared to the results in the dark. Furthermore, the mechanism of enhanced gas sensitivity was proposed based on the energy band alignment of the PdSe 2 /InSe heterojunction with the assistance of investigating the surface potential variations. This work may pave the way for the development of high-performance, room-temperature gas sensors based on 2D vdWs heterostructures through the LMBE technique.

Despite a growing neuroimaging literature on the pathophysiology of major depressive disorder (MDD), reproducible findings are lacking, probably reflecting mostly small sample sizes and heterogeneity in analytic approaches. To address these issues, the Depression Imaging REsearch ConsorTium (DIRECT) was launched. The REST-meta-MDD project, pooling 2428 functional brain images processed with a standardized pipeline across all participating sites, has been the first effort from DIRECT. In this review, we present an overview of the motivations, rationale, and principal findings of the studies so far from the REST-meta-MDD project. Findings from the first round of analyses of the pooled repository have included alterations in functional connectivity within the default mode network, in whole-brain topological properties, in dynamic features, and in functional lateralization. These well-powered exploratory observations have also provided the basis for future longitudinal hypothesis-driven research. Following these fruitful explorations, DIRECT has proceeded to its second stage of data sharing that seeks to examine ethnicity in brain alterations in MDD by extending the exclusive Chinese original sample to other ethnic groups through international collaborations. A state-of-the-art, surface-based preprocessing pipeline has also been introduced to improve sensitivity. Functional images from patients with bipolar disorder and schizophrenia will be included to identify shared and unique abnormalities across diagnosis boundaries. In addition, large-scale longitudinal studies targeting brain network alterations following antidepressant treatment, aggregation of diffusion tensor images, and the development of functional magnetic resonance imaging-guided neuromodulation approaches are underway. Through these endeavours, we hope to accelerate the translation of functional neuroimaging findings to clinical use, such as evaluating longitudinal effects of antidepressant medications and developing individualized neuromodulation targets, while building an open repository for the scientific community., Competing Interests: One of the authors, Dr Qi-Yong Gong, is also the editor-in-chief of Psychoradiology. He was blinded from reviewing or making decisions on the manuscript., (© The Author(s) 2022. Published by Oxford University Press on behalf of West China School of Medicine/West China Hospital (WCSM/WCH) of Sichuan University.)

Objective: The purpose of this study was to investigate the clinicopathologic factors associated with false-negative rate of sentinel lymph node biopsy (SLNB) in breast cancer, and to explore how to reduce the false-negative rate of SLNB., Methods: The clinicopathological data of 2265 patients with invasive breast carcinoma who underwent sentinel lymph nodes biopsy (SLNB) in Shandong Cancer Hospital between November 1999 and December 2011 were retrospectively analyzed. We screened 1228 patients who received axillary lymph node dissection after SLNB, and studied the clinicopathological factors that could be associated with false-negative rate of SLNB., Results: The false negative rate of this group was 10.7% (73/683), accuracy rate was 94.1% (1155/1228), and negative predictive value was 88.2% (545/618). Clinical tumor size (all P < 0.05), calendar year of surgery (all P < 0.05) and numbers of detected SLNs (all P < 0.05) were significantly related with false negative rate and accuracy rate of SLNB, determined by single factor analysis. Logistic regression model analysis showed that calendar year of surgery (P = 0.034) and numbers of detected SLNs (P = 0.012) were independent predictive factors for the false negative rate of SLNB., Conclusions: False negative rate and accuracy rate of SLNB are significantly related to the calendar year of surgery and number of detected SLNs. Strict case selection, standard operation procedure, increaseing numbers of detected SLNs, and improvement of the skill of operators are effective measures to reduce the false negative rate of SLNB.

This study investigated the effect of Angelica sinensis polysaccharides (APS-3c) on rat osteoarthritis (OA) model in vivo and rat interleukin-1-beta- (IL-1 β -) stimulated chondrocytes in vitro. APS-3c was administrated into rat OA knee joints and had protective effects on rat OA cartilage in vivo. Primary rat articular chondrocytes were cotreated with APS-3c and IL-1 β   in vitro. 2~50  μ g/mL APS-3c had no effect on chondrocytes viability, whereas it increased the proteoglycans (PGs) synthesis inhibited by IL-1 β . Microarray analysis showed that the significant changes were concentrated in the genes which were involved in PGs synthesis. RT-PCR confirmed that treatment with APS-3c increased the mRNA expression of aggrecan and glycosyltransferases (GTs) inhibited by IL-1 β but did not affect the mRNA expression of matrix-degrading enzymes. These results indicate that APS-3c can improve PGs synthesis of chondrocytes on rat OA model in vivo and IL-1 β -stimulated chondrocytes in vitro, which is due to the promotion of the expression of aggrecan and GTs involved in PGs synthesis but not the inhibition of the expression of matrix-degrading enzymes. Our findings suggest the clinical relevance of APS-3c in the prospective of future alternative medical treatment for OA.

Objective: To explore the studies and application status of sentinel lymph node biopsy (SLNB) in breast cancer in China by statistically analyzing the relevant domestic literature., Methods: The literatures published from January 1999 to December 2005 were searched in the databases of China, Info, CBM and CNKI retrieval system with "breast tumor, SLN and SLNB" as the key words. A total of 88 manuscripts were selected with 2 new reports of SLNB. The successful rate, accuracy, false-negative rate and sensitivity of SLNB were analyzed by SPSS 10.0 statistical analysis software., Results: Among a total of 6282 patients, the detection rate of SLNB was 90.82% (5705/6282) and the overall false-negative rate 9.69% (259/2671). The prediction sensitivity, specificity, false positive rate, accuracy, negative and positive predictive value of SLN for axillary lymph nodes status were 90.30%, 99.64%, 0.41%, 86.52%, 92.11% and 99.55% respectively., Conclusion: SLNB can accurately predict the axillary lymph node metastasis. And its detection rate is correlated with patient age and tumor location. The detection rate and false-negative rate has nothing to do with the tracer injection site. A combined regimen has a higher detection rate and a low false negative rate. Affecting the whole breast, SLN is not correlated with a particular area of breast. The validation phase of SLNB in breast cancer is currently feasible in China.

Translational medicine is an emerging idea in current medical research area. Typically, for the purpose of bridging the gap between basic and clinical research, it not only emphasizes the urgency and necessity to break the traditional working formats, including single subject centered research team and limited cooperation among different scientific groups, but also highlights a more close and frequent interaction between basic scientist and clinician. In order to reach this goal, the theory and method of systems biology should be employed. This paper mainly focused on a central issue that how to carry out an investigation on early clinical diagnosis of xenobiotic-induced intrauterine growth retardation (IUGR) by using research concept of translational medicine and method of systems biology. Briefly, a hypothesis of common mechanism of IUGR was first proposed and subsequent validation was performed via integrating--omics (e.g. genomics, proteomics, cytomics, metabonomics/metabolomics) and molecular biology techniques. Metabonomics was further utilized to explore IUGR biomarker and establish preliminary forecasting model by bioinformatics and computational biology, which is available for early diagnosis of IUGR and make a complement to current evaluation criteria.

Objective: The purpose of the present study was to explore the expression and clinical significance of multiple tumor suppressor gene 1 (MTS1) and cyclooxygenase-2 (COX-2) gene in invasive breast cancers., Methods: Flow cytometry was used to analyze the expression level of MTS1 and COX-2 in cancer tissues and corresponding para-cancer tissues from 66 cases of primary invasive breast cancers., Results: In breast cancer tissues, the expression of MTS1 and COX-2 assessed by relative fluorescence intensity were 0.84 and 10.54, respectively, and were 1.61 and 4.00 in corresponding para-cancer tissues, respectively. There was a significant difference between MTS1 and COX-2 expressions in cancer and corresponding para-cancer tissues (P <0.05). The differences of MTS1 and COX-2 expression of different ages, pathological types, tumor sizes or clinical stages of the breast cancer patients were not significant (P > 0.05). The MTS1 and COX-2 expressions were 1.12 and 5.94, respectively, in lymph node metastasis positive patients, and 0.79 and 13.05, respectively, in lymph node metastasis negative patients. The differences were significant (P <0.05)., Conclusion: The preliminary research results suggest that MTS1 and COX-2 gene expressions play fairly important role in tumorigenesis and progression of breast cancers. MTS1 and COX-2 protein expressions have correlation with lymph node metastasis. This study provides theoretical basis for use of COX-2 selective inhibitors in prevention and treatment for breast cancer patients.

Objective: To investigate the inhibitory and apoptosis regulating effects of adriamycin (ADM) on different human breast cancer cell lines and to evaluate the value of apoptosis in breast cancer treatment., Methods: Human breast cancer cells of the lines Bcap37 and MDA-MB-231 were cultured. ADM of different concentrations was added into the culture fluid. MTT method was used to detect the inhibition rate. Flow cytometry was used to detect the proliferation and apoptosis of the cells. To examine the expression of apoptosis-related molecules: Fas, mutant p53, and Bcl-2 proteins., Results: ADM inhibited the proliferation of Bcap37 cells and MDA-MB-231 cells dose and time-dependently, however, the inhibitory effect of ADM was stronger on the Bcap37 cells than on the MDA-MB-231 cells. After being treated by ADM the expression of Fas was increased and the expression of Bcl-2 was decreased in the Bcap37 cells. However, after being treated by ADM the expressions of Fas, Bcl-2, and mutant p53 in the MDA-MB-231 cells remained almost unchanged. Treated by ADM for 24 hours the apoptotic rate of the Bcap37 cells was increased from 0% to 5.8% (P < 0.05), however, no apoptosis was detected in the MDA-MB-231 cells after treatment of ADM at any time pint., Conclusion: With different molecular and biological characteristics, different breast cancer lines are different in chemosensitivity and drug-resistance, which are related to their apoptotic abilities induced by chemotherapeutic drugs.

Low levels of synthetic auxins are used as root growth promoters for a wide variety of botanicals. When properly used, they can produce earlier and more prolific root growth. Indole-3-succinic acid (ISA) is a chiral compound that can be synthesized as a racemate. Its enantiomers were resolved by both chromatography and diastereomeric crystallization. The absolute configuration of each enantiomer was determined by X-ray crystallography and then tested for auxin activity. The relative effectiveness of the ISA enantiomers was determined and compared to the achiral synthetic auxin indole-3-butyric acid and to the natural auxin indole-3-acetic acid.