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It has been an important approach of using matrix completion to perform image restoration. Most previous works on matrix completion focus on the low-rank property by imposing explicit constraints on the recovered matrix, such as the constraint of the nuclear norm or limiting the dimension of the matrix factorization component. Recently, theoretical works suggest that deep linear neural network has an implicit bias towards low rank on matrix completion. However, low rank is not adequate to reflect the intrinsic characteristics of a natural image. Thus, algorithms with only the constraint of low rank are insufficient to perform image restoration well. In this work, we propose a Regularized Deep Matrix Factorized (RDMF) model for image restoration, which utilizes the implicit bias of the low rank of deep neural networks and the explicit bias of total variation. We demonstrate the effectiveness of our RDMF model with extensive experiments, in which our method surpasses the state of art models in common examples, especially for the restoration from very few observations. Our work sheds light on a more general framework for solving other inverse problems by combining the implicit bias of deep learning with explicit regularization.

The capacitance and rate performance of Ti3CNTx-based films can be significantly improved by interlayer intercalation and surface modification.

A multilayer fabric consisting of PAN fibers with MXene coating prepared by time-difference blow-spinning exhibits remarkable EMI shielding due to synergistic effects of surface reflection, internal multiple scattering and multiple reflections.

Volatile flavor, as one of the important sensory substance in apples, directly influences customers’ choice and has attracted great attentions. In this study, representative ‘Fuji’ apples (Malus × domestica Borkh.) from Xinjiang and Shandong regions in China were chosen to study the influence of production regions, skin varieties (blushed and striped) and bagging management on the volatile flavor. About 40 volatile organic compounds were identified, mainly including esters and olefins. Bagging management reduced the differences in apple aroma components not significantly, and little difference was caused by skin varieties. While the production region had a significant impact on the difference in volatile and aroma substances compared to bagging management and skin variety. This study will provide key differential volatiles and their main influence factor for cultivation of ‘Fuji’ apple with good flavor quality.

IntroductionAbscisic acid (ABA) is an important sesquiterpene compound that regulates the stress resistance of plants. Botrytis cinerea can synthesize ABA via the mevalonic acid pathway. To identify the functional genes that are involved in the biosynthesis of ABA, we performed insertion mutagenesis into B. cinerea TB-31.MethodsWe obtained the ABA-reduced mutant E154 by insertion mutagenesis, and we identified the insertion site was located upstream of the gene bcfrp1 by Thermal asymmetric interlaced PCR. We performed a detailed phenotypic characterization of the bcfrp1 knockout and complementation mutants in TB-31. Furthermore, transcriptome and proteome analyses were conducted to explore how bcfrp1 affects the level of the ABA biosynthesis.ResultsThe bcfrp1 gene encodes an F-box protein. The phenotypic results confirmed the positive contribution of bcfrp1 to the biosynthesis of ABA and growth. Between TB-31 and ΔBcfrp1, we obtained 4,128 and 1,073 differentially expressed genes and proteins, respectively. The impaired ABA biosynthesis in the ΔBcfrp1 mutants was primarily affected by the different levels of expression of the ABA biosynthetic gene cluster and the genes involved in the mevalonic acid pathway. In addition, we further characterized the differentially expressed genes and proteins that participated in the growth, secondary metabolism, and signal transduction in B. cinerea based on the transcriptome and proteome data.DiscussionThis research based on the transcriptome and proteome analyses to display the changes after the deletion of bcfrp1 in B. cinerea TB-31, will help us to explore the molecular mechanism of ABA biosynthesis in B. cinerea.

Background The safety and short-term outcomes of gastrectomy after preoperative chemotherapy plus immunotherapy (PCIT) versus preoperative chemotherapy (PCT) in patients with advanced gastric cancer (AGC) remain unclear. This study was conducted to compare the safety and short-term efficacy of PCIT with those of PCT in patients with AGC. Methods We retrospectively reviewed the data of patients with AGC who received PCIT or PCT at Peking University Cancer Hospital and Institute Gastrointestinal Cancer Center I between January 2019 and June 2021. The clinical characteristics were recorded, and short-term oncological outcomes were compared. Independent t tests, Mann‒Whitney U tests, chi-square tests, and Fisher’s exact tests were used to calculate differences. The correlation analyses were performed using Pearson correlation. All p values were two-sided, and a p value Results A total of 162 AGC patients were included in this study, including 25 patients who received PCIT and 137 patients who received PCT. There were no significant differences in preoperative treatment-related adverse events (TRAEs) between the PCIT group and the PCT group (p = 0.088). Compared with the PCT group, the PCIT group had comparable postoperative functional recovery, with no significant differences in terms of time to first aerofluxus (p = 0.349), time to first defecation (p = 0.800), time to liquid diet (p = 0.233), or length of stay (p = 0.278). No significant differences were observed in terms of postoperative complications (p = 0.952), postoperative pain intensity at 24, 48, or 72 h (p = 0.375, p = 0.601, and p = 0.821, respectively), or postoperative supplementary analgesic use between the two groups (p = 0.881). In addition, the postoperative complication rate was 33.3% following laparoscopic approaches and 31.2% following open approaches in the PCIT group, with no significant difference (p = 1.000). Conclusion In patients with AGC, gastrectomy with D2 or D2 + lymphadenectomy after PCIT had comparable short-term oncological outcomes to PCT.

BackgroundThe optimal indications of staging laparoscopy in gastric cancer to detect peritoneal carcinomatosis are still controversial. We performed this systematic review and meta-analysis to quantify the relevance of the preoperative factors with peritoneal carcinomatosis to explore the indications of staging laparoscopy.Materials and methodsSystematic searches were conducted using Medline, Embase, and the Cochrane Library in December 2021. On the basis of calculating the odds ratio (OR) of each factor, we quantified the association between the risk factors and peritoneal carcinomatosis such as clinical T/N stage, Borrmann type, and tumor markers, using meta-analysis with a random-effects model.ResultsA total of 21 case-control studies and one cohort study were obtained. T stage, N stage, and differentiation degree were most widely studied, with OR values of 2.96 (95% CI: 1.87–4.69), 1.22 (95% CI: 0.86–1.73), and 1.91 (95% CI: 1.42–2.56), respectively. Among all the factors, elevated CA125 (OR = 19.45, 95% CI: 4.71–80.30), Borrmann type IV (OR = 7.68, 95% CI: 3.62–16.27), and large tumor diameter (OR = 5.12, 95% CI: 2.55–10.31) had the highest OR. In particular, CA125 had the best predictability for peritoneal carcinomatosis but was only mentioned by three articles.ConclusionsThere was a cognitive gap between the awareness and importance of risk factors for peritoneal carcinomatosis. In addition to T4 stage, patients with factors with high OR, such as Borrmann type IV, large tumor diameter, and elevated CA125, should undergo staging laparoscopy.

Apple flavor quality is vital for fruit assessment and the competitiveness. Complex apple flavor constitution is normally determined by complicated detection methods, which make simple, fast, and effective quality determination a challenge. In this study, the representative Fuji apples (Malus × domestica Borkh.) from Xinjiang and Shandong regions in China were selected to establish a simple and effective method for flavor assessment. Appearance, soluble solid content (SSC), and ethylene release changes of the fruits were monitored. During 65 days of storage, SSC, representing sugar content, kept stable as storage became longer, while the ethylene release exhibited dynamic changes with a peak and a reflection point, which reflected the physiological information of fruit. Moreover, ethylene could also reflect the aroma condition of the fruit in previous study. Therefore, SSC, together with ethylene, can stand for the flavor quality characteristics of apple fruits. Especially, both of them can be obtained independently by rapid nondestructive technologies, providing a new sight and strategy for the simple and effective flavor quality detection of Fuji apples.

Background Laparoscopic gastrectomy (LG) for gastric cancer has rapidly developed and become more popular in recent decades. Additional high-quality randomized controlled trial (RCT) studies comparing LG versus open gastrectomy (OG) for gastric cancer (GC) have been published in recent years. An updated systematic review is warranted. The aim of our meta-analysis was to comprehensively evaluate the short- and long-term outcomes of LG versus OG for GC. Materials and methods The PubMed, Embase, Web of Science, and Cochrane Center Register of Controlled Trials databases were comprehensively searched to identify RCTs comparing LG versus OG for GC published between January 1994 and December 7, 2021. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Cochrane Collaboration and the Quality of Reporting of Meta-analyses (QUORUM) guidelines. All RCTs comparing the short- and long-term outcomes of LG with those of OG were included. A random effects model was adopted with significant heterogeneity (I2 > 50%), while a fixed effects model was employed in all other cases (I2 ≤ 50%). Results A total of 26 RCTs with 8301 patients were included in this meta-analysis. The results indicated that the intraoperative complication rate was comparable between the LG group and the OG group (OR=1.14, 95% CI [0.76, 1.70], I2=0%, p=0.53). The LG group had fewer postoperative complications than the OG group (OR=0.65, 95% CI [0.57, 0.74], I2=26%, pI2=10%, p=0.10; OR=1.11, 95% CI [0.59, 2.09], I2=0%, p=0.74, respectively). The number of lymph nodes retrieved by the LG group was less than that of the OG group (MD=−1.51, 95% CI [−2.29, −0.74], I2=0%, pI2=23%, p=0.003), but the distal resection margin distance in the two groups was comparable (MD=−0.21, 95% CI [−0.47, 0.04], I2=0%, p=0.10). The time to first ambulation was shorter in the LG group than in the OG group (MD=−0.14, 95% CI [−.26, −0.01], I2=40%, p=0.03). The time to first flatus was also shorter in the LG group than in the OG group (MD=−0.15, 95% CI [−0.23, −0.07], I2=4%, p=0.0001). However, the first time on a liquid diet was comparable between the two groups (MD=−0.30, 95% CI [−0.64, 0.04], I2=88%, p=0.09). Furthermore, the postoperative length of stay was shorter in the LG group than in the OG group (MD=−1.26, 95% CI [−1.99, −0.53], I2=90%, p=0.0007). The 5-year overall survival (OS) was comparable between the two groups (HR=0.97, 95% CI [0.80, 1.17], I2=0%, p=0.73), and the 5-year disease-free survival (DFS) was also similar between the LG group and OG group (HR=1.08, 95% CI [0.77, 1.52], I2=0%, p=0.64). Conclusion LG is a technically safe and feasible alternative to OG with the advantages of a fewer postoperative complication rate, faster recovery of gastrointestinal function, and greater cosmetic benefit for patients with GC. Meanwhile, LG has comparable long-term outcomes to OG for GC.

BackgroundPeritoneal carcinomatosis (PC) of gastric cancer indicates a poor outcome and is mainly diagnosed by staging laparoscopy (SL). This study was designed to develop a risk stratification model based on the number of risk factors to exempt low-risk patients from unnecessary SL.MethodsThis was a retrospective cohort study based on a single institution between January 2015 and December 2019. SL is indicated for patients of advanced locoregional stage, and clinicopathologic characteristics of 535 consecutive patients were included. PC-associated variables were identified by logistic regression analysis. A risk stratification model based on the number of risk factors was constructed, and we defined its predictive value with a receiver operating characteristic (ROC) curve and negative predictive value.ResultsIn total, 15.9% of included patients were found to have PC during SL. Borrmann type IV, elevated CA125, and tumour diameter ≥5 cm were independent risk factors of PC. These three factors combined with cT4 were selected as predictive factors, and the number of predictive variables was significantly related to the possibility of PC (2.0%, 12.8%, 20.0%, 54.2%, and 100%, respectively). When the cutoff value is more than one predictive factor, the negative predictive value is 98.0%, with an area under the curve of 0.780. This model could exempt 29.8% of unnecessary SL compared to the indication of the current NCCN guideline.ConclusionsWe constructed a simple model to predict the probability of PC using the number of predictive factors. It is recommended that patients without any of these factors should be exempt from SL.

Purpose This study was conducted to compare the safety and short-term efficacy of gastrectomy after preoperative chemotherapy plus immunotherapy (PCIT) versus preoperative chemotherapy (PCT) in patients with advanced gastric cancer (AGC).Methods We retrospectively reviewed the data of patients with AGC who received PCIT or PCT at Peking University Cancer Hospital and Institute Gastrointestinal Cancer Center I between January 2019 and June 2021. The clinical characteristics were recorded, and short-term oncological outcomes were compared. Independent t-tests, Mann-Whitney U tests, Chi-square tests, and Fisher’s exact tests were used to calculate differences. The correlation analyses were performed using Pearson correlation. All p values were two-sided, and a p-value Results A total of 162 AGC patients were included in this study, including 25 patients receiving PCIT and 137 patients receiving PCT. There were no significant differences in preoperative treatment-related adverse events (TRAEs) between the PCIT group and the PCT group (p=0.088). Compared with the PCT group, the PCIT group had comparable postoperative functional recovery, with no significant differences in terms of the first aerofluxus time (p=0.349), the first defecating time (p=0.800), the first time on liquid diets (p=0.233), and length of stay (p=0.278). No significant differences were observed in terms of postoperative complications (p=0.952), postoperative pain intensity at 24, 48, and 72 hours (p=0.375, p=0.601, and p=0.821, respectively), and postoperative supplementary analgesic between the two groups (p=0.881). In addition, the postoperative complication rates were 33.3% following the laparoscopic approaches and 31.2% following the open approaches in the PCIT group, with no significant difference (p=1.000).Conclusions In patients with AGC, gastrectomy with D2 or D2+ lymphadenectomy after PCIT was comparable to PCT in terms of short-term oncological outcomes. The safety of LG was similar to that of OG in patients with AGC after PCIT.

Fuji apple (Malus × domestica Borkh.) is a popular fruit cultivar and occupies an important position in the fruit market due to its excellent flavor and storage quality. Ethylene emission can induce respiration, which would reduce postharvest quality and increase storage losses. In order to maintain fruit quality and extend shelf life, apples are usually stored in a low-temperature environment after harvest to reduce the formation of ethylene. Volatile aroma components are regarded as one of the most important aspects of flavor quality and a key factor for apple quality grading and customer satisfaction. Ethylene emission and its relationship with volatile aromas during low temperature, however, have not been determined. In this study, the dynamic changes of volatile aroma compounds of Fuji apples stored at 4 °C were detected and analyzed for 42 days. The variation of ethylene released from Fuji apple was studied correspondingly. The results showed that ethyl butyrate, ethyl caproate, ethyl 2-methylbutyrate and 2-methylbutyl acetate were the main aroma components of Fuji apple. The change in ethylene emission and the normalized peak area of volatile aroma compounds exhibited a similar tendency that increased significantly from the 3rd day to the peak on the 14th day and then decreased; there was a positive linear correlation between them with a correlation coefficient of 0.79 (P < 0.05). Therefore, ethylene release can be used as a potential indicator for evaluation of volatile aroma compounds in apples. Using ethylene emission as an indicator could reduce the difficulty and complexity of volatile aroma evaluation, which could be a new non-destructive inspection choice for apple flavor quality assessment.

The educational quality of research master’s degree can be in part reflected by the examiner score of the thesis. This study focuses on finding positive predictors of this score with the aim of developing assessment and prediction methods for the educational quality of postgraduates. This study is based on regression analysis of the characteristics extracted from publications and references involving 1038 research master’s theses written at three universities in China. The analysis indicates that for a thesis, the number and the integrated impact factor of its references in Science Citation Index Expanded (SCIE) journals are significantly positive predictors of having publications in such journals. Additionally, the number and the integrated impact factor of a thesis’ representative publications, defined as the publications authored by the master’s student as a first author or second author with tutors in lead position, in SCIE journals, are significantly positive predictors of its examiner score. Based on these predictors, a range of indicators is provided to assess thesis quality, to measure the contributions of disciplines to postgraduate education, to predict postgraduates’ research outcomes, and to provide benchmarks regarding the quality and quantity of their reading work.

A solution of NH3 detection based on catalytic conversion of NH3 into NOx was proposed by using MOS gas detectors and Pt-supported catalysts. The catalysts convert NH3 into NOx, which is a very sensitive analyte for MOS detectors. Catalysts based on Pt-loaded HZSM-5 and Al2O3 were prepared by wet impregnation. MOS detectors were fabricated from nanosized In2O3 and WO3 using screen-printing techniques. As expected, MOS sensors based on In2O3 and WO3 have an extremely high sensitivity to NO2; nevertheless, they have a relatively low response to NH3 and a large cross-sensitivity to typical interfering gases such as CO and ethanol. By the present solution, MOS sensors could very sensitively respond to NH3, even down to 0.25 ppm. In addition, it was also found that the catalysis also combusts the reducing gases into CO2 and water and consequently significantly improves the selectivity of NH3. Lastly, we would to like to stress that the proposed concept of the catalytic conversion method suggests the potential utility for broader measurements by using different catalysts and gas detectors and that only a part of the usage for NH3 was presented here.

Stacking different two-dimensional (2D) nanomaterials into composite structures opens an opportunity to fabricate electrodes combining the advantages of the individual nanomaterials. Here, different types of MXene nanosheets are combined to create flexible all-MXene hybrid films with high gravimetric capacitance and excellent rate performance for flexible supercapacitors. Ti3C2Tx nanosheets are introduced in between Nb2CTx layers, leading to a significantly increased interlayer spacing. The self-restacking of both types of MXene nanosheets is effectively impeded, accelerating the diffusion of electrolyte ions and enabling more accessible 2D nanochannels. The freestanding Ti3C2Tx/Nb2CTx films deliver a high gravimetric capacitance of 370 F g−1 at a scan rate of 2 mV s−1, good rate performance with 56.1% capacitance retention at 200 mV s−1 and a long cycle life. Furthermore, the energy density of the assembled all-solid-state symmetric supercapacitor can reach up to 5.5 mW h g−1 at a power density of 141.4 mW g−1. Serving as a stable power source unit, the all-solid-state supercapacitor was also integrated with a flex sensor to fabricate a self-powered device. The route to fabricate Ti3C2Tx/Nb2CTx hybrid films with enhanced electrochemical performance is also applicable for other MXenes, promoting the application of MXenes in flexible supercapacitors and integrated electronic devices.

The quality of masters’ dissertations is an important index of graduate education, which can be in part reflected through the grades given by experts. This study aims to find the factors positively correlated to the grades, and then use them to predict the grades and quality of dissertations. We applied four typical machine learning models to calculate the impacts of several factors extracted from the contents of dissertations on the grades. It shows that the random forest model outperforms logistic regression, support vector machine, and naive Bayes on recognizing the dissertations with a high grade. It also shows that the quantity of publications is the most important predictor to the grades, compared with the quantity of publications, the length of dissertations, the quantity and quality of references. And the quality of references is a significant predictor of producing high quality publications. Those findings can be utilized to predict and recognize high quality dissertations.

Quantifiable predictability in the citation counts of articles is significant in scientometrics and informetrics. Many metrics based on the citation counts can evaluate the scientific impact of research articles and journals. Utilising time series models, an article’s citation counts up to the yth year after publication can be predicted by those up to the previous years. However, the typically used models cannot predict the fat tail of the actual citation distributions. Thus, based on cumulative advantage of the citation behaviour, we propose a method to predict the accumulated citation counts, by using a random number sampled from a power-law distribution to modify the results given by a recurrent neural network (RNN), long short-term memory. Extensive experiments on the data set including 17 journals in information science verified the effectiveness of our method by the good fittings on distributions and evolutionary trends of the citation counts of articles. Our method has the potential to be extended to predict other popular assessment measures such as impact factor and h-index for journals.

The monitoring of ethylene is of great importance to fruit and vegetable quality, yet routine techniques rely on manual and complex operation. Herein, a chemiresistive ethylene sensor based on reduced graphene oxide (rGO)/tungsten diselenide (WSe2)/Pd heterojunctions was designed for room-temperature (RT) ethylene detection. The sensor exhibited high sensitivity and quick p-type response/recovery (33/13 s) to 10–100 ppm ethylene at RT, and full reversibility and excellent selectivity to ethylene were also achieved. Such excellent ethylene sensing behaviors could be attributed to the synergistic effects of ethylene adsorption abilities derived from the negative adsorption energy and the promoted electron transfer across the WSe2/Pd and rGO/WSe2 interfaces through band energy alignment. Furthermore, its application feasibility to banana ripeness detection was verified by comparison with routine technique through simulation experiments. This work provides a feasible methodology toward designing and fabricating RT ethylene sensors, and may greatly push forward the development of modernized intelligent agriculture.

Background Among locally advanced gastric cancer (LAGC) patients, poor response to initial neoadjuvant chemotherapy (NAC) is associated with unfavorable outcomes; however, changing the postoperative therapy regimen in this group of patients is unclear. We compared the poor responders who continued the original protocols with that of patients who switched treatment after NAC plus D2 gastrectomy. Methods Our study included LAGC patients who achieved tumor regression grade 3 according to the American Joint Committee on Cancer/College of American Pathologists system, after NAC, between December 2006 and December 2017 at our institution. Outcomes were overall survival (OS), progression-free survival (PFS), and adverse events during postoperative treatment. The propensity score matching method was used to match patients. Results Overall, 160 patients were enrolled in the final analysis set, including 21 switched cases and 139 non-switched cases. A 1:2 matched cohort (21 switching vs. 42 non-switching) was generated to eliminate all confounding factors. No statistical differences were observed in OS and PFS, either in the whole patients (OS: log-rank p = 0.804; PFS: log-rank p = 0.943) or in the matched cohort (OS: log-rank p = 0.907; PFS: log-rank p = 0.670) between the two groups. Patients with changed regimens had a significantly higher rate of peripheral neurotoxicity (p = 0.045). Contrarily, a lower rate of overall adverse events was observed in the non-switching group with marginal significance (p = 0.069). Conclusion Adjusting to a non-cross-resistant regimen only by post-NAC pathological evaluation may not be sufficient for designing an effective treatment route for LAGC poor responders. Treatment change required a more scrutinized clinical track, which involved a multifaceted assessment.

BackgroundEpstein–Barr virus-associated gastric cancer(EBVaGC)has a unique tumor immune microenvironment. We performed a comprehensive analysis of the tumor-infiltrating immune cells in a cohort of EBVaGC in a Chinese population.MethodsEpstein–Barr encoding region (EBER) in situ hybridization was performed in 1,328 consecutive cases of surgically resected GC. Densities of immune cells, including T cells, B cells, natural killer cells, and macrophages from the patients were calculated after immunohistochemical staining with CD3, CD20, CD57, and CD68 antibodies in tissue microarrays, respectively.ResultsEBVaGC patients accounted for 4.1% (55 of 1,328) cases in the overall population. The average age of patients with EBVaGC was lower than that of non-EBVaGC patients. Histologically, EBVaGC patients exhibited poorly differentiated adenocarcinoma (P = 0.004) and lower frequency of vascular invasion (P = 0.034). The density of CD3+ T lymphocytes (CD3, 23.84 ± 14.49 vs. 12.76 ± 8.93, P < 0.001) and CD68+ macrophages (CD68, 9.73 ± 5.25 vs. 5.44 ± 4.18, P < 0.001) was significantly higher in EBVaGC patients. CD3+ T cell density predicted better 5-year overall survival of EBVaGC patients (P = 0.022).ConclusionsEBVaGC patients were younger with low-differentiated adenocarcinoma and less vascular invasion. Increased infiltration of multiple immune cells affected the prognosis of patients, especially EBVaGC patients with more CD3+ T lymphocytes, who survived longer.

In this research, single-factor and response surface experiments were conducted in the fed-batch fermentation process to improve the yield of iturin A. The effect of adding various concentrations of precursor amino acids l-asparagine (Asn), l-aspartic acid (Asp), l-glutamic acid (Glu), l-glutamine (Gln), l-Serine (Ser) and l-proline (Pro) at different adding times (3 and 12 h) on iturin A production and cell growth was studied. The respective addition of amino acids (Asp 0.28 g/L; Asn 0.36 g/L; Glu 0.20, 0.28 and 0.360 g/L; Gln 0.20, 0.28 and 0.36 g/L; Pro 0.12, 0.20, 0.28 and 0.36 g/L) at 3 h was shown to improve cell growth but did not affect the yield of iturin A. Meanwhile, the individual addition of the same amino acids at 12 h improved cell growth and increased the yield of iturin A. Excellent correlation was obtained between the predicted and measured values, suggesting that the regression model was accurate and reliable; highly significant (P

Network embedding is an important method to learn the low-dimensional representation of nodes. It can be used to reduce the dimension of the network for downstream tasks. Many existing embeddings learn the representation only based on the reconstruction of the topological structure, yet nodes with attributes can provide important information in many real networks. Thus, learning attributed graph embedding should not only be based on the reconstruction of topological structure but also node features. In this paper, we propose a reasonable and interpretable graph autoencoder based on structure and attributes. This model can also be extended in both supervised and unsupervised tasks. Experiments including link prediction, clustering, and graph visualization have verified the effectiveness of our proposed GAE model.

In this research, single-factor and response surface experiments were conducted in the fed-batch fermentation process to improve the yield of iturin A. The effect of adding various concentrations of precursor amino acids l-asparagine (Asn), l-aspartic acid (Asp), l-glutamic acid (Glu), l-glutamine (Gln), l-Serine (Ser) and l-proline (Pro) at different adding times (3 and 12 h) on iturin A production and cell growth was studied. The respective addition of amino acids (Asp 0.28 g/L; Asn 0.36 g/L; Glu 0.20, 0.28 and 0.360 g/L; Gln 0.20, 0.28 and 0.36 g/L; Pro 0.12, 0.20, 0.28 and 0.36 g/L) at 3 h was shown to improve cell growth but did not affect the yield of iturin A. Meanwhile, the individual addition of the same amino acids at 12 h improved cell growth and increased the yield of iturin A. Excellent correlation was obtained between the predicted and measured values, suggesting that the regression model was accurate and reliable; highly significant (P

A solution of NH

To improve the ecological situation, the Chinese government launched the Beijing-Tianjin sandstorm source control project in 2001. Concurrently, a series of ecological restoration strategies were i...

Objective Diagnostic laparoscopy is recommended for the pretherapeutic staging of gastric cancer to detect any unexpected or unconfirmed intra-abdominal metastasis. The aim of this study was to evaluate the role and indications of diagnostic laparoscopy in the detection of intra-abdominal metastasis. Methods Standard diagnostic laparoscopy with peritoneal cytology examination was performed prospectively on patients who were clinically diagnosed with primary local advanced gastric cancer (cT≥2M0). We calculated the rate of intra-abdominal metastases identified by diagnostic laparoscopy, and examined the relationship between peritoneal dissemination (P) and cytology results (CY). Split-sample method was applied to find clinical risk factors for intra-abdominal metastasis. Multivariate logistic regression analysis and receiver-operator characteristic (ROC) analysis were performed in training set to find out risk factors of intra-abdominal metastasis, and then validate it in testing set. Results Out of 249 cM0 patients, 51 (20.5%) patients with intra-abdominal metastasis were identified by diagnostic laparoscopy, including 20 (8.0%) P1CY1, 17 (6.8%) P0CY1 and 14 (5.6%) P1CY0 patients. In the training set, multivariate logistic regression analysis and ROC analysis showed that the depth of tumor invasion on computer tomography (CT) scan ≥21 mm and tumor-occupied ≥2 portions of stomach are predictive factors of metastasis. In the testing set, when diagnostic laparoscopy was performed on patients who had one or two of these risk factors, the sensitivity and positive predictive value for detecting intra-abdominal metastasis were 90.0% and 32.1%, respectively. Conclusions According to our results, depth of tumor invasion and tumor-occupied portions of stomach are predictive factors of intra-abdominal metastasis.

Let S n 2 be the graph obtained by the strong prism of a star Sn, i.e. the strong product of K2 and Sn. In this paper, explicit expressions for Kirchhoff index, multiplicative degree-Kirchhoff index and number of spanning tress of S n 2 are determined, respectively. More specially, let S n , r 2 be the set of subgraphs obtained by randomly deleting r vertical edges from S n 2 , where 0 ≤ r ≤ n. Explicit formulas for Kirchhoff index and number of spanning trees for any graph S n , r 2 ∈ S n , r 2 are established, respectively. Moreover, the Kirchhoff index of S n , r 2 is almost three-eighths of its Wiener index.

In recent years, the international status of agriculture in the BRICS countries&mdash, Brazil, Russia, India, China and South Africa&mdash, has been continuously improved. In 2018, the gross agricultural production of the BRICS countries accounted for more than 50% of the world&rsquo, s total. Further strengthening the developing cooperation of the BRICS countries is of great significance for ensuring global food security. Based on the data from FAOSTAT and UN Comtrade Database, this study builds a food self-sufficiency rate and food security cooperation potential index to quantitatively analyze the food security status, cooperation effectiveness, and future trends of the BRICS countries. The study finds that the overall food security of the BRICS countries is generally showing a trend of volatility and growth, with high rates for cereals and relatively low rates for fresh products. In the future, BRICS food security cooperation should be based on their own resource endowment and socioeconomic characteristics. The BRICS countries need to constantly improve the awareness of joint cooperation and action in the future, focusing on scientific and technological cooperation, information sharing, complementary advantages in trade, and improving the global competitiveness of products. With the help of agricultural science and technology, Brazil is growing as a strong export country of food products. Russia needs to increase the introduction of agricultural science and technology and foreign capital to give full play to its resource advantages. India can improve its food self-sufficiency faster by the construction of a BRICS Agricultural Research Platform. China makes full use of BRICS resources, actively promotes agricultural enterprises to go global, and constantly optimizes the food supply structure. South Africa maintains the advantages of fruit and vegetable industry and increases the introduction and promotion of agricultural science and technology to improve the domestic food production capacity.

Background Preoperative diagnosis of peritoneal metastasis with gastric cancer remains challenging. This study explored the abnormal computed tomography (CT) signs of occult peritoneal metastasis (OPM) and evaluated it by region-to-region comparison using staging laparoscopy, from which a 4-point CT score system was developed. Methods Patients with advanced gastric cancer (stage cT ≥ 2M0) diagnosed by CT were enrolled in the study. Occult peritoneal metastasis detected during staging laparoscopy was compared with preoperative CT to investigate the presence of abnormal signs by a region-to-region comparison. A 4-point CT score system was developed to define the radiologic characteristics. Subsequently, the diagnostic efficacy of the CT score system was prospectively verified. Results In this study, 57 OPM regions were detected by staging laparoscopy in 33 of the 385 enrolled patients. The greater omentum was the most frequent site of OPM (38.60%, 22/57), which usually exhibited a smudge-like ground-glass opacity (S-GGO) (90.91%, 20/22) with a mean CT score of 2.14. The parietal and perihepatic peritoneum was the second most common site (22.81%, 13/57). A 4-point CT score system was developed based on the results. A cutoff CT score of 2 or higher was associated with a false-negative rate of 2% (2/99). This CT score system had a sensitivity of 87.5% and a specificity of 76.4% for an OPM-positive diagnosis (area under the curve, 0.848). The agreement between two radiologists on the assigned final score was 76.2% (kappa, 0.5). Conclusions Patients with OPM mostly exhibited S-GGO on CT, which should be interpreted cautiously. The 4-point CT score system may improve the pretreatment evaluation of occult peritoneal metastasis, and staging laparoscopy might not be necessary for patients with a score lower than 2.

IntroductionCurrent guidelines recommend open gastrectomy with D2 lymph node dissection and adjuvant chemotherapy as the standard treatment for advanced gastric cancer. However, the prognosis is not satisfactory. Perioperative chemotherapy has been proposed to improve survival. Although still in debate, the efficacy of laparoscopic distal gastrectomy (LDG) in patients with advanced gastric cancer has been demonstrated in a few trials. Therefore, LDG after neoadjuvant chemotherapy can be a candidate for future standard treatment on advanced distal gastric cancer. We propose a randomised phase II trial to compare LDG and open distal gastrectomy (ODG) after neoadjuvant chemotherapy for advanced gastric cancer.Methods and analysisTo test the efficacy and safety, a randomised, open-label, single-centre, phase II trial was designed to evaluate the non-inferiority of LDG compared with ODG after neoadjuvant chemotherapy, with 3-year recurrence-free survival as the primary endpoint. The chosen critical value of a non-inferiority margin was an increase of Ethics and disseminationThis study was approved by the Peking University Cancer Hospital Ethics Committee. The results will be submitted for publication in peer-reviewed journals.Trial registration numberNCT02404753; Pre-results.

Thermal stability is very important for real application of bulk heterojunction (BHJ) solar cells. In this work, we report the thermal stability and degradation behavior of the BHJ solar cells. The evolution of the local structures and in situ charge separation and transport were revealed by electrical scanning probe microscopy (ESPM). The BHJ solar cells are composed of a 2D conjugated thienyl-substituted BDT with substituted TT (PBDTTT-C-T) or conventional semicrystalline poly(3-hexylthiophene) (P3HT) as the electron donors and [6,6]-phenyl C61-butyric acid methyl ester (PCBM) or indene-C60 bisadduct (ICBA) as the acceptors. Among these four material pair-wise combinations, the PBDTTT-C-T/ICBA combination show highest thermal stability (the PCE declined by 10.77%) while the P3HT/PCBM combination shown worst (declined by 42.82%). Morphological and charge information with nanoscale resolution were provided. The hole transport and mobility of the P3HT-based BHJ blend films declined significantly after the aging treatment. However, for the PBDTTT-C-T-based BHJ system, the hole current was even enhanced. Physical evolution processes were proposed to depict the thermal aging effects within the active layer. This work provides new insights into the rational design of thermally stable photovoltaic systems by considering mesoscopic heterogeneity.

To investigate the current status of diagnosis and treatment of early gastric cancer in China, based on the nationwide survey by China Gastrointestinal Cancer Surgery Union.The union sent questionnaires on basic diagnosis and treatment data of gastric and colorectal cancer to all the centers of the union. Different centers collected and summarized their data by year and sent back the questionnaires to the e-mail of theunion(gi_union@foxmail.com) for summary.From 2014 to 2016, the union collected 285 questionnaires from 85 centers all over China. In these 3 years, a total of 88 340 cases of gastric cancer were summarized and there were 17 187 cases of early gastric cancer (part of the data was not available in some centers). The proportion of early gastric cancer varied from 19.5%(5711/29290) in 2014 to 19.0%(6081/32050) in 2015 and 20.0%(5395/27000) in 2016. Significant difference was found among them (χThe data report of China Gastrointestinal Cancer Surgery Union partly reflects the epidemiologic characteristics, current status of diagnosis and treatment of early gastric in China.

The dietary patterns determine the nutrition structure and suitable nutrition benefits for health. In order to measure the relationship between nutrition and health, this article focuses on the relationship between Dietary patterns and health expenditure. We collected 547 household samples from six counties in rural Hainan Province of China. The authors applied Seemingly Unrelated Regression (SUR) model to estimate the empirical model. The results are: (1) some animal food have significant effect to health expenditure; (2) based on the current analysis, consuming more pork and eggs, health expenditure would significantly increase; while consuming more chicken and fish, health expenditure would significantly decrease. We could conclude that appropriate dietary pattern benefits health; livestock meat consuming, primarily pork, may cause more health care expenditure, while fish-dominant diet could reduce health expenditure

BACKGROUND Over the past 10 years, food safety incidents have occurred frequently in China. Food safety issues in the dairy sector have increasingly gained the attention of the Chinese government and the public. The objective of this research is to explore consumption changes of dairy products of different income groups after these dairy safety incidents. RESULTS The research indicates that consumers' response to dairy safety risk is very intense. Dairy consumption has experienced a declining trend in recent years, and the impact of dairy safety incidents has lasted for at least 5 years. Until 2012, dairy consumption had not yet fully recovered from this influence. Using the random effects model, this study examined the relationship between food safety incident and consumption. CONCLUSIONS Overall, the results show that consumers in the low-income group are more sensitive to safety risk than those in the high-income group. It can be seen from this paper that the decrease of urban residents' dairy consumption was mainly driven by changes in fresh milk consumption, while the decline of milk powder consumption, which was affected by the melamine incident, was relatively moderate, and milk powder consumption for the high-income group even increased. © 2015 Society of Chemical Industry

The effect of methanol addition on the heterologous expression of isoprenyl transferase NovQ was studied in Pichia pastoris Gpn12, with menadione and isopentenol as precursors to catalyze vitamin K2 (MK-3) synthesis. The expression of NovQ increased by 36% when 2% methanol was added every 24 h. The influence of initial pH, temperature, methanol addition, precursors (menadione, isopentenol) addition, catalytic time and cetyltrimethyl-ammonium bromide (CTAB) addition were explored in the P. pastoris whole-cell catalytic synthesis process of MK-3 in shaking flask. Three significant factors were then studied by response surface method. The optimal catalytic conditions obtained were as follows: catalytic temperature 31.56 ℃, menadione 295.54 mg/L, catalytic time 15.87 h. Consistent with the response surface prediction results, the optimized yield of MK-3 reached 98.47 mg/L in shaking flask, 35% higher than that of the control group. On this basis, the production in a 30-L fermenter reached 189.67 mg/L when the cell catalyst of 220 g/L (dry weight) was used to catalyze the synthesis for 24 h. This method laid the foundation for the large-scale production of MK-3 by P. pastoris Gpn12.对异戊烯基转移酶NovQ 在毕赤酵母Gpn12 异源表达过程中诱导剂甲醇添加量进行了探究，并以毕赤酵母Gpn12 全细胞为酶源，以甲萘醌、异戊烯醇为前体，催化合成维生素K2 (MK-3)。每24 h 添加2%甲醇时，NovQ表达量提高约36%。考察摇瓶中初始pH、温度、甲醇添加量、前体 (甲萘醌、异戊烯醇) 添加量、催化时间、十六烷基三甲基溴化铵 (CTAB) 添加量等7 个因素对Gpn12 全细胞催化合成MK-3 的影响，发现催化温度、甲萘醌添加量、催化时间影响显著，对3 个显著因素进行响应面优化得出催化条件为：催化温度31.56 ℃，甲萘醌添加量295.54 mg/L，催化时间15.87 h，优化后的摇瓶MK-3 产量达到98.47 mg/L，与响应面预测结果一致，较优化前对照组提高了35%。在30 L 发酵罐进行生物催化实验，催化时间24 h，细胞催化剂浓度220 g (干重)/L，MK-3 产量达到189.67 mg/L。该方法为Gpn12 规模化生产MK-3 奠定了一定的基础。.

Gas sensors based on reduced graphene oxide (rGO) films and rGO/MoS

Gastric cancer is the fourth most common cancer worldwide and the leading cause of tumor-related death in China. Gastric cancer is a heterogeneous disease and therefore requires different treatments based on the subtype. We describe a patient who had gastric cancer with liver metastases. Biopsy and tumor analysis using the HercepTest revealed a human epidermal growth factor receptor 2 (HER2)-positive adenocarcinoma as confirmed by fluorescence in situ hybridization. The patient was treated with a regimen of trastuzumab, oxaliplatin, and S-1 (six cycles). When positron emission tomography findings suggested that the metastases had resolved, the patient underwent surgery. Histopathologically, no cancer cells were observed in the resected hepatic tissue. The patient underwent tumor resection surgery, during which the tumor and gastric lymph nodes with lesions were removed. The patient has remained disease-free for 3 months. Therefore, trastuzumab may be an effective agent in the chemotherapeutic treatment of liver metastases in patients with HER2-positive gastric adenocarcinoma.

As the development of information technology and intelligent tutoring, web-based learning has been widely used nowadays to help people acquire knowledge in a flexible way. Especially, web-based learning services can greatly facilitate farmers to gain knowledge on farming. It is observed that learning goals and preferences tend to be localized for farming knowledge due to similar climate and soil conditions in an area. Therefore, geographical information can be utilized to recommend agricultural learning resources. In this paper, an agricultural learning resource recommendation approach is proposed using agent-based simulation that takes geographical information into account. The agent simulation environment is introduced. A distance-aware agent reputation model is presented. A multi-agent collaborative recommendation approach is proposed. Simulation experiments are conducted for the evaluation of the proposed approach. The results show good performance of it.

Social tagging becomes prevailing with the emergence of Web 2.0 communities recently. By utilizing this additional valuable information from user-created tags, it is convenient to understand users’ interests and behavior so that we can provide good user experience in applications of various domains. Therefore, the definition of profile is crucial for tagging systems. Furthermore, it is important to have recommendations for various groups of users. In recipe recommendations, older people typically have different needs compared with young users. In this paper, we first focus on the definitions of user profile, item feature and how to derive semantics from these sources. Afterwards, we design the framework of the tag-based multimedia recipe recommendation system (MRRS). Finally, we conduct preliminary experimental study of recipe recommendations for different age groups. The result shows that older people concern more about the nutrition aspects of recipes.

The gene lasB from Pseudomonas aeruginosa, which encoded elastase, was cloned and firstly successfully expressed in Pichia pastoris stain KM71 under the control of AOX promoter. The effects on the recombinant elastase activities of different pH, different temperatures and different metal ions were assayed. The full-length gene (1497 bp) encodes a preproenzyme including an N-terminal signal peptide (23 aa), a propeptide (197 aa) and mature elastase (301 aa). The recombinant elastase was secreted into culture supernatants using signal sequence from lasB and showed a single band at about 34 kDa by SDS-PAGE. The recombinant elastase expression hit the highest level of approximately 450 mg/L and the specific elastolytic activity of the recombinant elastase was 130 U/ml, which was approximately 26-fold higher than that of elastase obtained from P. aeruginosa. The optimal temperature and pH of the recombinant elastase was 28 degrees C and 7.4, respectively. The enzyme possessed high resistance to heat, and can be activated by Ca(2+). These enzyme properties suggested that it could be produced in an industrial scale and has the potential to be a commercial enzyme.

Purpose Angiogenesis is a promising therapeutic target to inhibit tumor growth. This review summarizes data from clinical trials of anti-angiogenic agents in gastric cancer. Design A systematic search of PubMed, Embase and conference databases is performed to identify clinical trials with specific anti-angiogenic agents in gastric cancer treatment Results The risk of disease progression (37–52%) and death (19–22%) with ramucirumab as second-line treatment decreases in phase III trials in advanced gastric cancer. No significant improvement in overall survival (OS) with the addition of bevacizumab to chemotherapy is shown. Bevacizumab or ramucirumab combined with traditional chemotherapy is associated with higher adverse event rate compared to chemotherapy alone. Except for apatinib, phase II trials of other tyrosine kinase inhibitors (TKIs) may improve overall response rate, but there are no significant improvements in OS and progression-free survival (PFS) when combined with chemotherapy. Conclusion Phase III trials in advanced gastric cancer have demonstrated improved outcome with ramucirumab as second-line treatment. Most of the other studies on anti-angiogenic agents in gastric cancer have reported improvement in response rate but not in OS compared to chemotherapy alone. Future research is expected in optimizing the anti-angiogenic therapy combined with traditional treatment.

Over the past 10 years, food safety incidents have occurred frequently in China. Food safety issues in the dairy sector have increasingly gained the attention of the Chinese government and the public. The objective of this research is to explore consumption changes of dairy products of different income groups after these dairy safety incidents.The research indicates that consumers' response to dairy safety risk is very intense. Dairy consumption has experienced a declining trend in recent years, and the impact of dairy safety incidents has lasted for at least 5 years. Until 2012, dairy consumption had not yet fully recovered from this influence. Using the random effects model, this study examined the relationship between food safety incident and consumption.Overall, the results show that consumers in the low-income group are more sensitive to safety risk than those in the high-income group. It can be seen from this paper that the decrease of urban residents' dairy consumption was mainly driven by changes in fresh milk consumption, while the decline of milk powder consumption, which was affected by the melamine incident, was relatively moderate, and milk powder consumption for the high-income group even increased.