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The Internet and 5G era makes e-learning a vital part of modern education, and extensive evidence has shown that peer teaching and flipped classroom contribute to increased success in medical teaching. However, the applicability of these pedagogies in laboratory courses remains largely unexplored. This study aimed to evaluate the academic performance, proficiency in procedural skills, and perception of nursing students in physiology laboratory classes delivered with nontraditional classroom (NTC) pedagogies comprising the combination of e-learning, peer teaching, and flipped classroom. Each class was subdivided into two equal halves by successive student identification (ID) number and randomly assigned to the control or NTC group. Compared to the control class, NTC teaching significantly enhanced mean score of six preclass tests (67.77 ± 9.83 vs. 62.94 ± 9.70), with "B" graders increased obviously, suggesting that preclass e-learning was more effective than textbook-based preview, especially for general grasp of the topic. Similarly, average scores on postclass quizzes in the NTC group were improved (79.40 ± 9.12 vs. 74.43 ± 8.88). Lesser time cost and higher success rates were observed in trachea, artery, and heart catheterizations in the NTC group, although no disparities were found in ureteral intubation. The majority (~74%) of students supported the reform and shared positive experiences with NTC methodology. They reported that virtual experiments and self-paced procedural skill videos affected pre- and in-class learning outcomes most, respectively. These findings indicated that NTC pedagogy was workable to improve students' subject scores and proficiency in complicated and direct-viewing procedural skills and was favorable to students.

The specific objective of this study was to use a logistic regression model for determining the degree to which egg laying patterns of individual females at the end of life (i.e., terminal segments) in each of three different fruit fly species could be distinguished from the egg-laying patterns over a similar period in midlife (i.e., non-terminal segments). Extracting data from large-scale databases for 11-day terminal and 11-day non-terminal segments in the vinegar fly (Drosophila melanogaster), the Mexican fruit fly (Anastrepha ludens) and the Mediterranean fruit fly (Ceratitis capitata) and organizing the model's results in a 2 × 2 contingency table, we found that: (1) daily egg-laying patterns in fruit flies can be used to distinguish terminal from non-terminal periods; (2) the overall performance metrics such as precision, accuracy, false positives and true negatives depended heavily on species; (3) differentiating between terminal and non-terminal segments is more difficult when flies die at younger ages; and (4) among the three species the best performing metrics including accuracy and precision were those produced using data on D. melanogaster. We conclude that, although the reliability of the prediction of whether a segment occurred at the end of life is relatively high for most species, it does not follow precisely predicting remaining life will also be highly reliable since classifying an end of life period is a fundamentally different challenge than is predicting an exact day of death.

Abstract Background Porphyromonas gingivalis plays an oncogenic role in development and progression of esophageal squamous cell carcinoma (ESCC). However, the impact of P. gingivalis on local recurrence of early ESCC or precancerous lesion after ESD treatment remains unknown. The present study aimed to evaluate the impact of P. gingivalis on local recurrence after ESD treatment of early ESCC or high-grade dysplasia (HGD). Methods The amount of P. gingivalis was assessed by immunohistochemistry in 205 patients with early ESCC or HGD. Univariate and multivariate Cox regression analyses were performed to determine the effect of P. gingivalis on local recurrence. Propensity score matching analysis was performed to reduce the imbalance of baseline characteristics. A nomogram integrating significant prognostic factors was built for local recurrence prediction. Results The amount of P. gingivalis increased significantly in neoplasms that invaded up to muscularis mucosa and submucosa compared with lesions confined to epithelium or lamina propria. Overabundance of P. gingivalis was positively associated with invasion depth, post-ESD stricture and local recurrence. Univariate and multivariate Cox regression analyses revealed that P. gingivalis, longitudinal length of lesion and lymphovascular invasion were independent predictors for post-ESD recurrence. A nomogram comprising P. gingivalis, lymphovascular involvement, and lesion length performed well for prediction of post-ESD local recurrence with the concordance indices of 0.72 (95%CI, 0.62 to 0.80), 0.72 (95%CI, 0.63 to 0.80), and 0.74 (95%CI, 0.65 to 0.83) in the validation cohort, the entire cohort, and the subcohort after PSM, respectively. Conclusion P. gingivalis overabundance is a risk factor and a potential predictor for local recurrence of early ESCC or HGD after ESD treatment. Thus, clearance of P. gingivalis represents an attractive strategy for prognosis improvement and for prevention of ESCC.

We review the motivation, goals, and achievements of the Photonic Integrated Networked Energy efficient datacenter (PINE) project, which is part of the Advanced Research Projects Agency-Energy (ARPA-E) ENergy-efficient Light-wave Integrated Technology Enabling Networks that Enhance Dataprocessing (ENLITENED) program. The PINE program leverages the unique features of photonic technologies to enable alternative mega-datacenters and high-performance computing (HPC) system architectures that deliver more substantial energy efficiency improvements than can be achieved through link energy efficiency alone. In phase 1 of the program, the PINE system architecture demonstrated an average factor of 2.2 ×2.2× improvement in transactions/joule across a diverse set of HPC and datacenter applications. In phase 2, PINE will demonstrate an aggressive 1.0 pJ/bit total link budget with high-bandwidth-density dense wavelength-division multiplexing (DWDM) links to enable additional 2.5 ×2.5× or more efficiency gains through deep resource disaggregation.

In order to deal with the chromatic dispersion-induced power fading issue for short-reach direct-detection optical fiber communication applications, such as the ever-increasing data-center interconnections (DCIs), optical filed recovery is intensively being under investigation. To date, various direct detection schemes capable of optical field recovery have been proposed, including the Kramers–Kronig (KK) receiver, asymmetric self-coherence detection (ASCD) receiver, carrier-assisted differential detection receiver (CADD), Stokes vector receiver (SVR), and carrier-free phase-retrieval (CF-PR) receiver. Among those, the CF-PR receiver attracts lots of research attention because it can circumvent the requirement of a strong continuous-wave (CW) optical carrier for the beating with the signal. Generally, the CF-PR receiver consists of only two single-ended photodiodes (PDs) and one dispersive element, for the field recovery of the quadrature amplitude modulation (QAM) signals. Based on the theoretical and experimental studies reported so far, this paper reviews the latest progress of CF-PR receivers designed for high-speed optical short-reach transmission links.

Tiebangchui, which mainly originates from the dried root of Aconitum pendulum Busch, is an important traditional Tibetan medicine and has long been used for the treatment of various types of cold and pain. However, the excellent pharmacological activities of Tiebangchui are accompanied by high toxicity caused by Aconitum alkaloids. To ensure clinical medication safety, Tiebangchui is only used after processing. Stir-frying with Zanba is an effective and unique processing method in traditional Tibetan medicine, but chemical variations in raw and processed Tiebangchui are rarely reported. In this study, an integrated method combining ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and desorption electrospray ionization mass spectrometry imaging (DESI-MSI) was applied to explore chemical constituent variations, transformation mechanisms, and in situ spatial distributions of metabolites in raw Tiebangchui and its series of processed products. Three important diterpenoid alkaloids were quantified by HPLC. Results revealed visible differences between raw Tiebangchui and its Zanba stir-fried products, and 60 min was demonstrated to be the proper processing time. A total of 64 components were detected, and 32 of them were considered as metabolic markers to distinguish raw Tiebangchui and its processed products stir-fried for different time. Chemical changes were also visualized by DESI-MSI: the contents of aconitine and 3-deoxyaconitine significantly decreased, and those of benzoylaconine, benzoyldeoxyaconine, 16-epi-pyrodeoxyaconitine, and 16-epi-pyroaconitine markedly increased. Transformations from diester-diterpenoid alkaloids to monoester-diterpenoid alkaloids through hydrolysis and pyrolysis were found to be the major detoxication processes during Zanba stir-frying. In summary, UPLC-Q-TOF-MS based metabolomics, DESI-MSI, and quantitative combined approach could be an efficient method to characterize chemical variations in Tiebangchui and its Zanba processed products with different stir-frying time. The wide application of this method would contribute to the process monitoring and safe control of Tiebangchui and other toxic Aconitum medicine.

Converting low-cost inorganic chemicals into value-added organic chemicals is a longstanding goal in chemistry. Here the authors describe a silver-catalysed chemoselective carbene N−H insertion reaction, providing access to primary amines from aqueous ammonia and diazo compounds.

Objective: In order to evaluate the difference of characteristic flavor intensity between different times of cyclic stewed beef. Methods: The volatile flavor compounds in circulating stewed beef were determined by solid phase microextraction-gas chromatography-mass spectrometry （SPME-GC-MS）, and the key flavors with important contribution were screened out according to the relative odor activity value. The flavor substances contributed by circulating stewed beef were analyzed by principal component analysis, the flavor intensity evaluation model of cyclic stewed beef was established, and the comprehensive evaluation of cyclic stewed beef was carried out combined with sensory evaluation. Results: The seven key flavourings were n-hexanal, undecanal, nonanal, n-hexanol, 3-methylpentane, cineole and anethole. The results showed that the contribution rates of the first to third principal components obtained by principal component analysis were 52.40%, 25.64% and 12.95% respectively, and the cumulative contribution rate was 90.98%, which could represent the main information of volatile flavor substances in cyclic stewed beef. The correlation coefficient between the characteristic flavor intensity of the model and the sensory score was 0.90（P＜0.05）. Conclusion: The model can be applied to the flavor evaluation of cyclic stewed beef.

Abstract Melanoma, one of the most aggressive malignancies, its high mortality and low survival rates are associated with effective metastatic colonization. Melanoma metastasis hinges on the bidirectional cell-cell communication within the complex metastatic microenvironments (MME). Extracellular vesicles (EVs) are recognized as a new class of molecular mediator in MME programing. Published studies show that melanoma EVs can educate MME stromal cells to acquire the pro-metastatic phenotype to enhance metastatic colonization. Whether EVs can mediate the interactions between heterogenous cancer cells within the MME that alter the course of metastasis has not been investigated at the mechanistic level. In this study, melanoma parental cells (MPCs) and paired derivative cancer stem cell line melanoma stem cells (MSCs) that were derived from melanoma cell line M14 were used. We demonstrate that the EVs-mediated crosstalk between the MSCs and the MPCs is a novel mechanism for melanoma metastasis. We characterized miR-592, a relatively novel microRNA of prognostic potential, in mediation of such intercellular crosstalk. EVs can encapsulate and deliver miR-592 to target MPCs. Upon entering, miR-592 inhibits the expression of its gene target protein tyrosine phosphatase non-receptor type7 (PTPN7), a phosphatase targeting MAPKs. This leads to the relief of the inhibitory effect of PTPN7 on MAPK/ERK signaling and consequently the augmentation of metastatic colonization of MPCs. Thus, via the extracellular vesicle miR-592/PTPN7/MAPK axis, melanoma-CSCs can transfer their metastatic ability to the low-metastatic non-CSC melanoma cells.