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Due to the pivotal role of Recommender Systems (RS) in guiding customers towards the purchase, there is a natural motivation for unscrupulous parties to spoof RS for profits. In this paper, we study Shilling Attack where an adversarial party injects a number of fake user profiles for improper purposes. Conventional Shilling Attack approaches lack attack transferability (i.e., attacks are not effective on some victim RS models) and/or attack invisibility (i.e., injected profiles can be easily detected). To overcome these issues, we present Leg-UP, a novel attack model based on the Generative Adversarial Network. Leg-UP learns user behavior patterns from real users in the sampled ``templates'' and constructs fake user profiles. To simulate real users, the generator in Leg-UP directly outputs discrete ratings. To enhance attack transferability, the parameters of the generator are optimized by maximizing the attack performance on a surrogate RS model. To improve attack invisibility, Leg-UP adopts a discriminator to guide the generator to generate undetectable fake user profiles. Experiments on benchmarks have shown that Leg-UP exceeds state-of-the-art Shilling Attack methods on a wide range of victim RS models. The source code of our work is available at: https://github.com/XMUDM/ShillingAttack., Accepted by TNNLS. 15 pages, 8 figures

Purpose We aimed to evaluate the effect of luteal phase support (LPS) on pregnancy outcome in natural cycle frozen embryo transfer (NC-FET). Method We searched PubMed, Cochrane Library, Embase for related literature from start to February 2020. Relative risk ratio (RR) and 95% confidence intervals (95% CI) in random-effects, fixed-effects models were calculated using Review Manager 5.3. Results Totally 9 studies were included in the meta-analysis. The results showed no significant difference could be found regarding chemical pregnancy rate (RR 1.07, 95% CI 0.93-1.22; I2 = 54%) and miscarriage rate (RR 0.92, 95% CI 0.70-1.22; I2 = 0%) between the LPS groups and no LPS groups in NC-FET. LPS groups has increased the rate of clinical pregnancy rate (RR 1.23, 95% CI 1.12-1.34; I2 = 52%) compared with no LPS groups. Subgroup analysis according to trigger administration also showed a significant difference between the two groups. Conclusion LPS might improve the clinical pregnancy rate in NC-FET. HCG trigger for ovulating may result in luteal phase deficiency. LPS subsequently improved clinical pregnancy rate and chemical pregnancy rate for patients undergoing HCG trigger and NC-FET. Retrospectively registered This meta-analysis was registered at PROSPERO, PROSPERO ID is CRD42020171758.

BackgroundTumor metastasis with poor prognosis is still the leading cause of deaths among triple-negative breast caner (TNBC) patients. Therefore, understanding the underlying molecular mechanisms of TNBC metastasis and identifying the molecules contributing to the process are of great importance.It would be provided targets for the prevention and treatment of recurrence and metastasis of TNBC. MethodsThe expression level of MAP3K1 and its up-or downstream genes,SOX2 and KLF4 were detected using Western blotting assay. Cell migration and proliferation were measure by xCELLigence Real-Time Cell Analyzer (RTCA). Protein interaction was used for co-immunorecipitation. ResultCompared with metastasis (Met) in TBNC model, the expression of MAP3K1,KLF4,ERK1/2, C-jun and werelower, while SOX2, Ras,Rafand c-Fos were higher in non-metastasis (non-Met) samples. In MAP3K1 silenced MDA-MB-231 cells, the cell proliferation and metastasis rates were increased. The expression level of KLF4 was lower than SOX2 reduced or minimal interaction of both. In SOX2 silenced MDA-MB-231 cells, the cell proliferation and metastasis rates were decreased, while the expression of KLF4 and MAP3K1 were higher, the interaction of MAP3K1 and KLF4 was inhibited. ConclusionsIt is demonstrated for the very first time that SOX2 and MAP3K1 are playing an important rolesin TNBC cell metastasis by regulating MAPK signaling pathway by interacting with KLF4 .

This systematic review sought to evaluate the clinical outcomes of vitrification at the cleavage stage and blastocyst stage for embryo transfer in patients undergoing assisted reproductive technology (ART) treatment. We searched for related comparative studies published in the PubMed, EMBASE, and Cochrane Library databases up to July 2017. The primary outcomes were clinical pregnancy rate (CPR) and embryo implantation rate (IR). Secondary outcomes were multiple pregnancy rate (MPR), miscarriage rate (MR), live birth rate (LBR), and ongoing pregnancy rate (OPR). The Mantel-Haenszel fixed effects model and random effects model were used to analyze the summary risks ratios (RRs) with 95% confidence intervals (CIs). Eight studies with more than 6590 cycles were included in our meta-analysis. Seven studies were observational retrospective comparative studies. One was a prospective study. Overall, the current study summarizes information from 6590 vitrification warming cycles (cleavage stage n = 4594; blastocysts n = 1996). There was no difference in the primary outcome clinical pregnancy rate (RR = 0.97, 95% CI = 0.90–1.04; fixed effects model; I 2 = 21%), whereas vitrified blastocyst transfer was significantly superior to vitrified cleavage-stage embryo transfer regarding the implantation rate (RR = 0.85, 95% CI = 0.74–0.97; random effects model; I 2 = 43). Regarding the secondary outcomes, no differences were found in the multiple pregnancy rate (RR = 1.20, 95% CI = 0.79–1.82; fixed effects model; I 2 = 22), live birth rate (RR = 1.07, 95% CI = 0.98–1.16; fixed effects model; I 2 = 0), and ongoing pregnancy rate (RR = 1.01, 95% CI = 0.92–1.120; fixed effects model; I 2 = 0), whereas a higher miscarriage rate was observed with vitrified blastocyst transfer (RR = 0.65, 95% CI = 0.45–0.93; random effects model; I 2 = 23). In summary, this meta-analysis shows that vitrification at any stage has no detrimental effect on clinical outcome. Blastocyst transfer will still remain a favorable and promising option in ART. Due to the small sample evaluated in the pool of included studies, large-scale, prospective, and randomized controlled trials are required to determine if these small effects are clinically relevant.

Sea-to-air fluxes of marine biogenic aerosols have the potential to modify cloud microphysics and regional radiative budgets, and thus moderate Earth's warming. Polar regions play a critical role in the evolution of global climate. In this work, we use a well-established biogeochemical model to simulate the DMS flux from the Greenland Sea (20°W–10°E and 70°N–80°N) for the period 2003–2004. Parameter sensitivity analysis is employed to identify the most sensitive parameters in the model. A genetic algorithm (GA) technique is used for DMS model parameter calibration. Data from phase 5 of the Coupled Model Intercomparison Project (CMIP5) are used to drive the DMS model under 4 × CO2 conditions. DMS flux under quadrupled CO2 levels increases more than 300% compared with late 20th century levels (1 × CO2). Reasons for the increase in DMS flux include changes in the ocean state—namely an increase in sea surface temperature (SST) and loss of sea ice—and an increase in DMS transfer velocity, especially in spring and summer. Such a large increase in DMS flux could slow the rate of warming in the Arctic via radiative budget changes associated with DMS-derived aerosols.

Problem Several recent studies have investigated the relationship between antinuclear antibodies (ANAs) and in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) outcomes. This meta-analysis evaluated the effect of ANA on clinical outcome for patients undergoing IVF/ICSI treatment. Method of study A systemic survey of the literature was performed using PubMed, EMBASE and the Cochrane Library databases, through January 2019. Evaluated outcomes included clinical pregnancy rate (CPR), miscarriage rate (MR) and implantation rate (IR). Relative risk ratio (RR) and 95% confidence intervals (95% CI) were used for dichotomous data. Meta-analyses were performed with Review Manager 5.3 software. Results Eleven eligible studies were found. For IVF/ICSI cycles, compared with an ANA(-) group, infertile patients with ANA(+) had significantly reduced incidence of CPR (RR 0.66, 95% CI 0.56-0.79; I2 = 60%) and IR (RR 0.61, 95% CI 0.49-0.76; I2 = 75%), and had a higher MR (RR 1.81, 95% CI 1.40-2.36; I2 = 48%). Conclusion This study suggested that ANA might cause poor pregnancy outcomes for infertile women undergoing IVF/ICSI treatment.

Previous studies have proven the existence of active brown adipose tissue (BAT) in adults; however, its effect on systematic metabolism remains unclear. The current study was designed to investigate the differences in the metabolic profiles of healthy adults with and without active BAT using positron emission tomography–computed tomography (PET-CT) scans in the un-stimulated state. A cross-sectional analysis was performed to assess the health of adults using PET-CT whole-body scans at Huashan Hospital Medical Centre between November 2009 and May 2010. A total of 62 healthy adults with active BAT were enrolled in the BAT-positive group. For each positive subject, a same-gender individual who underwent PET-CT the same day and who had no detectable BAT was chosen as the negative control. Body composition was measured, and blood samples were collected for assays of metabolic profiles and other biomarkers. In both the male and female groups, BAT-positive individuals were younger and had lower body mass indexes, fasting insulin, insulin resistance, and leptin, but a greater level of high-density lipoprotein cholesterol compared with the negative controls. In the male group, body fat content and levels of tumor necrosis factor-α were significantly lower in the BAT-positive than in the negative control group. The healthy adults with active BAT in an un-stimulated state had favorable metabolic profiles suggesting that active BAT may be a potential target for preventing and treating obesity and other metabolic disorders.

Cushing’s disease (CD) is remarkably prevalent among females; however, more severe clinical presentation and adverse outcomes have been found in males. The purpose of this study was to investigate the overall clinical profile and biochemical parameters in patients with CD to identify the gender differences. Here we describe our series of CD patients referred to our medical center during 2012-2013. Among 73 cases, females presented a marked preponderance compared to males. Males had significantly higher ACTH, BMI, HbA1c, systolic blood pressure, and hemoglobin than females. For the first time, the incidence of fatty liver and hepatic function was also shown to be elevated in males. Multiple linear regression analysis was performed to further investigate the correlation of risk factors with hypokalemia, HbA1c, and systolic blood pressure. Gender and serum cortisol were associated with hypokalemia. Age, gender, and serum cortisol were significantly associated with HbA1c. Additionally, only gender was significantly associated with systolic blood pressure. Regarding clinical presentation, purple striae seemed to occur more frequently in males than in females. Thus, more severe clinical presentation, biochemical parameters, and complications were found in males than in females. Clinical professionals should pay more attention to the diagnosis and management of males with CD.

Researches on Arctic aerosol, ice cover and cloud cover have received great attention and it related to the regional even global climate changing. We here study the distributions and the coupling relationships of AOD, cloud cover (CLD) and ice cover (ICE) in the Greenland Sea (20°W–10°E, 70°N–80°N) during 2003–2012. Enhanced statistics methods, such as lag regression method and co-integration analysis method are used for correlation and regression analysis. According to the 10 years satellite data, AOD was high in spring, and low in summer. Generally, AOD was higher down south and lower up north. CLD and AOD mainly had negative correlations and ICE and AOD had positive correlations. According to the lag regression analysis by statistical software EViews, both the peaks of CLD and peaks of ICE were all 1 month earlier than the peak of AOD. The co-integration test suggested that both ICE(-1) and CLD(-1) and AOD were all zero-order integration, and there was no unit root in the residual, so there all had long-run equilibrium relationships. ICE and AOD were stationary series, and the residual had no unit root, they were good coupling. The melting of sea ice and decreasing of cloud cover would all result in the increasing of the AOD content. However, the relationship between AOD and CLD was weaker than the relationship between AOD and ICE, indicating that the aerosol in Arctic mostly came from the sea rather than from the air.

Sparse representation classification is widely used in pattern recognition. In this paper, a k-nn and sparse represent based method for gesture recognition (KSRC) is proposed. In order to reduce the computational complexity problem in sparse representation, KSRC exploits K nearest neighbors of the testing sample from all training samples and represents the test sample as a linear combination of the K nearest neighbors, then solving the l1-norm constrained least square problem. Taking linear interpolation method to force all data to be in the same space. Experiments show almost perfect user-independent recognition, and user-mixed recognition and user-dependent recognition, and speeds up 4 times than SRC.

Environmental context Future changes in marine biogenic aerosol emissions in Arctic seas are likely to affect the radiative budget of the region. Here we employ a calibrated biogeochemical model to simulate change in sulfate aerosol emissions in the Barents Sea, and find strong increases occur by the late 21st century. If replicated across the Arctic Ocean, such increases in sulfate aerosol loading to the Arctic atmosphere may decrease the rate of warming at polar latitudes. Abstract Global warming of climate is connected to ecosystem change, especially in the polar oceans. Biogenic emissions of dimethylsulfide (DMS) are the main biogenic source of sulfate aerosols to the marine atmosphere and may change in the Arctic, where warming is currently very rapid. Here, we simulate DMS distribution and sea-to-air flux in the Barents Sea (30–40°E and 70–80°N) for the period 2003–05. A genetic algorithm is used to calibrate the key parameters in the DMS model. We use MODIS satellite chlorophyll-a data and regional DMS field data to calibrate the model. Owing to limited DMS observations in the Arctic Ocean, multiple data sources were used and compared. A back-propagation neural network is used for predicting regional DMS based on previous history time series. Parameter sensitivity analysis is done based on DMS flux output. Global climate model forcings for 1×CO2 to 3×CO2 conditions are used to force the biogeochemical model under future climate warming (c. 2080). The simulation results show that under tripled CO2, DMS flux would increase 168 to 279% from autumn through winter and would increase 112% during ice melting season. DMS flux would increase much more in ice-melt-affected water. The increased DMS flux under 3×CO2 indicates that regional warming could slow owing to the emission of DMS in the Arctic, if the increase in emissions of anthropogenic greenhouse gases is controlled.