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This purpose of the paper is to explore the optimal price strategy for the retailers under the cross-store full-reduction promotion mode, where speculative consumers will deliberately purchase add-on items to qualify for discounts when the purchase amount is less than the “full-reduction” threshold and then return the add-on items after successful payment. With respect to the optimal decision problem consisting of two online complementary retailers and an e-commerce platform in the face of speculative consumers’ add-on items return behavior, we construct the single-cycle sales decision models based on the revenue sharing contract. Furthermore, through the derivative function analysis method, we examine the effect of the proportion of speculative consumers, the proportion of product sharing discount amount and revenue sharing coefficient on the platform’s sale strategy and the retailers’ the optimal price strategy. The results show that whether platform implements cross-store full-reduction promotion strategy or not, the product price increases with the increase of revenue sharing coefficient. In addition, under the non-promotion sales mode, the optimal price is not affected by the speculative consumers’ behavior. Under the cross-store full-reduction promotion sales mode, the optimal price changes with the proportion of product sharing discount amount and the proportion of speculative consumers. And the price of only purchasing single product in this case is always higher than the price under the non-promotion sales mode. Finally, we compare the profits under the two scenarios, it is found that the profits under the cross-store full-reduction promotion sales mode are not always higher than that under non-promotion sales mode and the boundary conditions for the platform to adopt different modes are further given.

Introduction As the most common aggressive intraocular cancer in adults, uveal melanoma (UVM) threatens the survival and vision of many people. Glycolysis is a novel hallmark of cancer, but the role of glycolysis-related genes in UVM prognosis remains unknown. The purpose of the study was to establish a glycolysis-related gene signature (GRGS) to predict UVM prognosis. Methods Raw data were obtained from TCGA-UVM and GSE22138 datasets. The GRGS was established by univariate, LASSO and multivariate Cox regression analyses. Kaplan‒Meier survival and time-dependent receiver operating characteristic curves were used to evaluate the predictive ability of the GRGS. The relationships of the GRGS with infiltrating immune cell levels and mutations were analyzed with CIBERSORT and maftools. Results A novel GRGS (risk score = 0.690861*ISG20 +0.070991*MET -0.227520*SDC2 +0.690223*FBP1 +0.048008*CLN6-0.128520* SDC3) was developed for predicting UVM prognosis. The GRGS had robust predictive stability in UVM. Enrichment annotation suggested that the high-risk group had stronger adaptive immune responses and that the low-risk group had more innate immune cell infiltration. Moreover, BAP1 mutation was related to high risk, and SF3B1 mutation was related to low risk. Conclusions This study developed and validated a novel GRGS to predict UVM prognosis and immune infiltration. The signature revealed an association between glycolysis-related genes and the tumor microenvironment, providing new insights into the role of glycolysis in UVM.

This purpose of the paper is to make an in-depth study on the selection of the optimal shopping add-on items recommendation service strength strategy of the e-commerce platform with full-reduction promotion based on consumers’ heterogeneity preferences for discount amount and add-on items recommendation. With respect to the optimal decision problem consisting of an e-commerce platform who maximizes the profits and consumers who make purchase decision based on their utility, we construct a Stackelberg game model that reflects the interaction between platform’s recommendation service strength and consumers’ purchase willingness. Furthermore, through the derivative function analysis method, we examine the effect of reservation price, recommended commodity price and discount amount on the platform’s optimal recommendation service strength strategy. The results show that the discount amount, reservation price and consumer preference have different effects on the optimal add-on items recommendation service strength and the profit of the platform. Additionally, appropriate recommendation services strength is beneficial to enhance consumers’ willingness-to-pay and then increase the profits of the platform. Therefore, it is an effective way to improve the performance of the platform to reasonably formulate the basic discount amount, full-reduction promotion threshold and add-on items recommendation service strength.

Background In general, ZIF-8 tends to undergo ion responsive degradation in ionic solutions, which makes it difficult to maintain its original structure, thus restricting its direct application in biological settings. Methods ZIF-8 was synthesized using one-pot method and the ZIF-8/PCL scaffolds were built by a round mould or printed by melt electrowrittten (MEW) technology. Mineralization performance was evaluated by SEM with EDS-mapping and micro-CT scanning after soaking in simulated body fluid (SBF). The osteogenic activity in vivo or in vitro was assessed using different methods including micro-CT scanning, Alizarin red staining, and immunohistochemical staining. Results Herein, an abnormal phenomenon is reported that ZIF-8 can form large hydroxyapatite-like crystals when getting immersed directly in multi-ion simulated body fluid. The abnormal crystals showed the continuation of rapid growth in 14 days, with its volume increasing by more than ten times. As suggested by the release of Zn2+ and the emergence of new XRD diffraction peaks, ZIF-8 particles might gradually collapse and congregate through competitive coordination and re-nucleation. The above phenomenon is also observable on the surface of ZIF-8/PCL composite materials and MEW printing ZIF-8/PCL scaffolds. ZIF-8 increased the roughness of PCL by altering its surface topography, which significantly improved its biocompatibility and osteoinductivity both in vitro and in vivo. Notably, the capability of pro-biomineralization makes ZIF-8 also applicable in polylactic acid. Conclusions To sum up, the results shown in this study demonstrate that ZIF-8 can serve as a bioactive additive that enables the surface modification to synthetic polymers, which suggests its potential of application for in-situ bone regeneration.

This study aimed to evaluate the infection rate of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among different populations in Wuhan, China. This cross-sectional survey-based study examined the results of SARS-CoV-2-specific serological tests and RT-PCR tests for 4,454 community residents and 4,614 healthcare workers performed from May 15 to May 29, 2020. The healthcare workers were classified as administrative and logistical staff (n = 1,378), non-first-line healthcare workers (n = 2,630), or first-line healthcare workers (n = 606) according to their frequency of contact with coronavirus disease (COVID-19) patients. The positive rates of SARS-CoV-2-specific IgG, IgM, and RNA were 2.9%, 0.4%, and 0.1% for the community residents and 3.3%, 0.6%, and 0.2% for the healthcare workers, respectively. There were no statistically significant differences between the rates of the two groups. Spearman's correlation analysis showed that the frequency of contact with COVID-19 patients negatively correlated with the positive rates of RT-PCR (rs = -0.036, P = 0.016), but did not significantly correlate with the positive rates of IgM (rs = -0.006, P = 0.698) or IgG (rs = 0.017, P = 0.239). There was no statistically significant difference between the SARS-CoV-2-specific IgG, IgM, or RNA positive rates of the community residents and those of the healthcare workers. The positive rate of SARS-CoV-2 RNA was lower for the first-line healthcare workers than for the non-first-line healthcare workers and the administrative and logistical staff.

A series of Zn-incorporated nano-ZSM-5 zeolites were synthesized by a dry gel conversion (DGC) method using tetrapropylammonium hydroxide (TPAOH) as a single template, and their activity in methanol to aromatics (MTA) process was investigated. The characterization results revealed that the introduction of Zn species slightly decreased the crystal size with the formation of some agglomerated particles. We also demonstrated that new Lewis acid sites formed in Zn-incorporated nano-ZSM-5 zeolite at the expense of Bronsted acid sites. The amount of medium acid sites in Zn-modified samples increased with increasing of Zn contents. Catalytic evaluation results revealed that the selectivity of BTX and aromatics for the sample synthesized via direct synthesis (Zn-NZ5-3) is increased from 24.0% and 37.9% to 27.9% and 46.4%, respectively. In addition, the lifetime of the sample prepared by the direct synthesis (Zn-NZ5-3) was 33% longer than that of the impregnated sample, while the selectivity of BTX and aromatics was slightly higher.

In this study, we developed a novel, simple, rapid, and low-cost colloidal gold-based immunochromatography method, with filter paper replacing nitrocellulose membrane as the substrate. To obtain adequately immobilized protein, chitosan was used to functionalize the filter paper. After conditions and parameters were optimized, the novel immunochromatography method was applied for detection of sulfonamide residues in milk. Quantitative detection was accomplished using a smartphone and Photoshop software (Adobe Inc., San Jose, CA), allowing us to screen 13 sulfonamides with a limit of detection ranging from 0.42 to 8.64 μg/L and recovery ranging from 88.2 to 116.9% in milk. The proposed novel method performed similarly to the conventional method that uses a nitrocellulose membrane as the transport medium, and it had lower cost and better usability because of the inexpensive and easily available filter paper.

Antibiotic residues are major contaminants in milk because of their use in agriculture and animal husbandry. In particular, streptomycin, an aminoglycoside antibiotic, is a potential risk to consumers because of its ototoxicity, anaphylaxis, and growth inhibition. Herein, monoclonal antibodies for streptomycin were conjugated with europium microspheres to serve as detection probes for the development of a chromatographic time-resolved fluoroimmunoassay to detect streptomycin residues in milk. The method had a low detection limit of 0.58 µg/kg, a linear range of 0.8 to 6.25 μg/kg, and substantial recovery, from 85.6 to 108.3%. It showed slight cross-reactivity with another aminoglycoside analog. Strong correlations between the results of established chromatographic time-resolved fluoroimmunoassay and ultra-performance liquid chromatography-tandem mass spectrometry indicated that the established fluoroimmunoassay is a reliable method for rapid onsite detection of streptomycin in milk and it has great potential in food safety monitoring.

Secure and trusted cross-platform knowledge sharing is significant for modern intelligent data analysis. To address the trade-off problems between privacy and utility in complex federated learning, a novel differentially private federated learning framework is proposed. First, the impact of data heterogeneity of participants on global model accuracy is analyzed quantitatively based on 1-Wasserstein distance. Then, we design a multilevel and multiparticipant dynamic allocation method of privacy budget to reduce the injected noise, and the utility can be improved efficiently. Finally, they are integrated, and a novel adaptive differentially private federated learning algorithm (A-DPFL) is designed. Comprehensive experiments on redefined non-I.I.D MNIST and CIFAR-10 datasets are conducted, and the results demonstrate the superiority of model accuracy, convergence, and robustness.

Retinoblastoma (RB) is the commonest malignant tumor of the infant retina. Besides genetic changes, epigenetic events are also considered to implicate the occurrence of RB. This study aimed to identify significantly altered protein-coding genes, DNA methylation, microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and their molecular functions and pathways associated with RB, and investigate the epigenetically regulatory mechanism of DNA methylation modification and non-coding RNAs on key genes of RB via bioinformatics method. We obtained multi-omics data on protein-coding genes, DNA methylation, miRNAs, and lncRNAs from the Gene Expression Omnibus database. We identified differentially expressed genes (DEGs) using the Limma package in R, discerned their biological functions and pathways using enrichment analysis, and conducted the modular analysis based on protein-protein interaction network to identify hub genes of RB. Survival analyses based on The Cancer Genome Atlas clinical database were performed to analyze prognostic values of key genes of RB. Subsequently, we identified the differentially methylated genes, differentially expressed miRNAs (DEMs) and lncRNAs (DELs), and intersected them with key genes to analyze possible targets of the underlying epigenetic regulatory mechanisms. Finally, the ceRNA network of lncRNAs-miRNAs-mRNAs was constructed using Cytoscape. A total of 193 DEGs, 74 differentially methylated-DEGs (DM-DEGs), 45 DEMs, 5 DELs were identified. The molecular pathways of DEGs were enriched in cell cycle, p53 signaling pathway, and DNA replication. A total of 10 key genes were identified and found significantly associated with poor survival outcome based on survival analyses, including CDK1, BUB1, CCNB2, TOP2A, CCNB1, RRM2, KIF11, KIF20A, NDC80, and TTK. We further found that hub genes MCM6 and KIF14 were differentially methylated, key gene RRM2 was targeted by DEMs, and key genes TTK, RRM2, and CDK1 were indirectly regulated by DELs. Additionally, the ceRNA network with 222 regulatory associations was constructed to visualize the correlations between lncRNAs-miRNAs-mRNAs. This study presents an integrated bioinformatics analysis of genetic and epigenetic changes that may be associated with the development of RB. Findings may yield many new insights into the molecular biomarker candidates and epigenetically regulatory targets of RB.

Recent studies have reported that surfaces and objects in the rooms of infected patients that are frequently touched by both medical staff and patients could be contaminated with SARS-CoV-2. In December 2019, Wuhan China suffered the earliest from this COVID-19 pandemic, and we took that opportunity to investigate whether the SARS-CoV-2 RNA exists in the ward environment after a long time from exposure. We found that on the 28th day following the discharge of COVID-19 patients, SARS-CoV-2 RNA could still be detected on the surfaces of pagers and in drawers in the isolation wards. Thorough disinfection of the ward environment was subsequently performed, after which these surfaces in the isolation wards tested negative for the presence of SARS-CoV-2 RNA. The findings remind us that the contaminated environment in the wards may become potential infectious resources and that despite a long time from exposure, the thorough disinfection in the COVID-10 units after is still necessary.

BackgroundThe emerging 2019 novel coronavirus (2019-nCoV) has pushed several countries into state of emergency all over the world. The possible transmission of 2019-nCoV by conjunctiva is controversial and has substantial public health implications.MethodsA retrospective cohort study was initiated to investigate the possible transmission of 2019-nCoV through aerosol contact with conjunctiva. We enrolled 67 cases of confirmed or suspected cases of novel coronavirus pneumonia (NCP) during 17–28 Jan 2020. Nasopharyngeal and conjunctival swabs were collected for real time RT-PCR analysis to detect 2019-nCoV.Results63 patients were identified as laboratory-confirmed NCP and the remaining four were suspected NCP. Conjunctival swab samples from one NCP patient yielded positive PCR results and two NCP patients yielded probable positive PCR results. None of the three patients had ocular symptoms. The only one NCP patient with conjunctivitis as the first symptom had negative conjunctival sac 2019-nCoV test. Conjunctival swab samples from the four suspected cases of NCIP were negative.Conclusion2019-nCoV can be detected in the conjunctival sac of patients with NCP. Through clinical analysis, viral transmission via the conjunctival route was not supported by the data. Good clinical protection can effectively cut off the transmission path.

A time-resolved fluorescent immunochromatographic assay (TRFICA) was successfully developed for the sensitive, simultaneous, and quantitative detection of aflatoxin B1 (AFB1) and zearalenone (ZEN) ...

Six aflatoxins (AFs; AF B1, B2, G1, G2, M1 and M2) and six zearalenone (ZEN) analogs (ZEN, zearalanone, α-zeralanol, β-zeralanol, α-zearalenol, and β-zearalenol) were simultaneously extracted from edible and medicinal herbs using a group-specific immunoaffinity column (IAC) and then identified by ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS). The IAC was prepared by coupling N-hydroxysuccinimide-activated Sepharose 4B Fast Flow gel with two group-specific monoclonal antibodies. The column capacities to six AFs and six ZEN analogs ranged from 100.2 ng to 167.1 ng and from 59.5 ng to 244.4 ng, respectively. The IAC–UPLC–MS/MS method was developed and validated with three different matrices (Chinese yam [Dioscorea polystachya], Platycodon grandiflorum and coix seed [Semen Coicis]). Recoveries of twelve analytes from edible and medicinal herbs were in the range of 64.7%–112.1%, with relative standard deviations below 13.7%. The limits of quantification were in the range from 0.08 μg kg−1 to 0.2 μg kg−1. The method was proven to be sensitive and accurate, and suitable for the determination of real samples.

Background Impaired wound healing might be associated with many issues, especially overactive of reactive oxygen species (ROS), deficiency of blood vessels and immature of epidermis. N-acetylcysteine (NAC), as an antioxidant, could solve these problems by inhibiting overreactive of ROS, promoting revascularization and accelerating re-epithelialization. How to deliver NAC in situ with a controllable releasing speed still remain a challenge. Materials and Methods In this study, we combined collagen (Col) with N-acetylcysteine to perform the characteristics of sustained release and chemically crosslinked Col/NAC composite with polyamide (PA) nanofibers to enhance the mechanical property of collagen and fabricated this multi-layered scaffold (PA-Col/NAC scaffold). The physical properties of the scaffolds such as surface characteristics, water absorption and tensile modulus were tested. Meanwhile, the ability to promote wound healing in vitro and in vivo were investigated. Results These scaffolds were porous and performed great water absorption. The PA-Col/NAC scaffold could sustainably release NAC for at least 14 days. After cell implantation, PA-Col/NAC scaffold showed better cell proliferation and cell migration than the other groups. In vivo, PA-Col/NAC scaffolds could promote wound healing best among all the groups. Conclusion The multi-layered scaffolds could obviously accelerate the process of wound healing and exert better and prolonged effects.

A method is described to enhance the sensitivity of an immunochromatographic assay for clenbuterol (CLE) by making use of dually-labeled gold nanoparticles (GNPs), background fluorescence blocking, and immunomagnetic separation. The GNPs were labeled with biotinylated antibody and streptavidin, respectively, and dually labeled GNPs were obtained via the biotin-streptavidin interaction to amplify the detection signal. The fluorescent signal was blocked by dually labeled GNPs and decreased as the dually labeled GNPs aggregation increases on nitrocellulose membrane, which derived from fluorescent polyvinylchloride card. However, fluorescence (measured at excitation/emission wavelengths of 518/580 nm) recovers when CLE reacts with dually labeled GNPs. Immunomagnetic separation was first applied for sample pretreatment. This can offset the matrix effect and improves the sensitivity and accuracy of the assay. Under the optimal conditions, the limits of detection of CLE visually were 0.25 μg·L−1. In addition, clenbuterol can be quantified in swine urine with a 0.03 μg·L−1 detection limit. This is 60-fold lower than current immunochromatography. Response is linear in the 0.06–0.59 μg·L−1 concentration range, and the recoveries from spiked swine urine range from 81 to 115%.”

Cancer immunotherapy and tumor microenvironment have been at the forefront of research over the past decades. Targeting immune checkpoints especially programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) has made a breakthrough in treating advanced malignancies. However, the low response rate brings a daunting challenge, changing the focus to dig deeply into the tumor microenvironment for alternative therapeutic targets. Strikingly, the inhibitory immune checkpoint lymphocyte activation gene-3 (LAG-3) holds considerable potential. LAG-3 suppresses T cells activation and cytokines secretion, thereby ensuring immune homeostasis. It exerts differential inhibitory impacts on various types of lymphocytes and shows a remarkable synergy with PD-1 to inhibit immune responses. Targeting LAG-3 immunotherapy is moving forward in active clinical trials, and combination immunotherapy of anti-LAG-3 and anti-PD-1 has shown exciting efficacy in fighting PD-1 resistance. Herein, we shed light on the significance of LAG-3 in the tumor microenvironment, highlight its role to regulate different lymphocytes, interplay with other immune checkpoints especially PD-1, and emphasize new advances in LAG-3-targeted immunotherapy.

In 2-(N-morpholino)ethanesulfonic acid buffer (0.1 M, pH 6.0), manganese dioxide-modified silicon dioxide (SiO2@MnO2) nanocomposites were facilely synthesized under ultrasonic conditions. Given their good biocompatibility and evident brown color, SiO2@MnO2 nanocomposites were used as labels in immunochromatography sensor for high-throughput screening of antibiotic residues in milk within 10 min. Meanwhile, excessive amounts of antibiotic residues might cause certain diseases and inhibit the activities of glutathione reductase in human body through the food chain, altering glutathione (GSH) levels in the human serum. GSH can reduce MnO2 to Mn(II). This phenomenon can effectively quench the fluorescence of Au nanoclusters. Thus, a fluorescent platform based on SiO2@MnO2 nanocomposites and Au nanoclusters has been designed for sensitive detection of GSH in the human serum with a limit of detection of 1.23 nM. After the parameters were optimized, the developed detection platforms based on SiO2@MnO2 nanocomposites have been used to detect antibiotics and GSH in real samples (milk and human serum) with satisfactory results. Results demonstrated that the proposed SiO2@MnO2 nanocomposites hold great potential for applications in food safety and clinical diagnosis simultaneously.

A multiplex lateral flow immunoassay sensor based on highly luminescent green-emitting Au nanoclusters (AuNCs-MLFIA sensor) was successfully established for the simultaneous and quantitative determination of clenbuterol (Clen) and ractopamine (RAC) in swine urine. The antigens of Clen and RAC were dispersed on a nitrocellulose membrane as two test lines, and the Au nanoclusters were synthesized from 6-aza-2-thiothymine and l -arginine to obtain highly green luminescence and ultra-small nanoparticles (Arg/ATT/AuNCs). Free carboxyl groups on Arg/ATT/AuNCs enabled conjugation with biomolecules to afford an indicator for the biosensor. The AuNCs-MLFIA sensor is based on the indirect competition assay and could successfully detect samples within 18 min without sample pretreatment, qualitative results can be obtained by visual inspection under a UV lamp. The limits of detection of Clen and RAC by the naked eye were both 0.25 μg L−1. In addition, the AuNCs-MLFIA sensor allowed quantitative detection combined with a portable fluorescence reader. The half-maximal inhibitory concentrations of Clen and RAC were 0.06 and 0.32 μg L−1, respectively, with detection limits of 0.003 and 0.023 μg L−1. Thirty blind-spiked swine urine samples were analyzed by the AuNCs-MLFIA sensor and liquid chromatography–tandem mass spectrometry, and the results of the two methods showed a significant correlation. The newly developed AuNCs-MLFIA sensor overcomes several limitations of conventional LFIA sensors, including their low sensitivity, limitation to quantify analytes, and single-analyte detection.

We report the magnetocaloric effect in a Tb

Morphotropic phase boundary (MPB) have aroused wide interests due to the exotic properties exhibited by the compositions around MPB [Tb1−x Dy x Co2, PRL 104, 197201 (2010); Tb1−x Dy x Fe2, PRL 111, 017203 (2013)]. By combining the two MPB compositions Tb0.3Dy0.7Co2 and Tb0.3Dy0.7Fe2, we designed a pseudo-binary system Tb0.3Dy0.7(Co1−x Fe x )2. The phase diagram is determined from the temperature spectra of magnetic susceptibility and magnetization. A Griffiths-like phase appears above the Curie temperature and gradually vanishes as the Fe content increases to x = 0.8. Magnetic hysteresis and magnetoelastic behavior are also investigated. Compared with the Terfenol-D composition x = 1.0, x = 0.8 exhibits higher Curie temperature (707 K) and comparable magnetostriction (818 ppm), which may be used in the sensors or transducers at high temperature.

A spontaneous exchange bias (SEB) discovered by Wang et al. [Phys. Rev. Lett. 106 (2011) 077203.] after zero-field cooling (ZFC) has attracted recent attention due to its interesting physics. In this letter, we report a giant SEB tuned by Sb-doping in Ni50Mn38Ga12-xSbx Heusler alloys. Such an SEB was switched on below the blocking temperature of approximately 50 K. The maximum exchange bias HE can arrive at 2930 Oe in a Ni50Mn38Ga10Sb2 sample after ZFC to 2 K. Further studies showed that this SEB was attributable to interaction of superspin glass (SSG) and antiferromagnetic matix, which was triggered by the crossover of SSG from canonical spin glass to a cluster spin glass. Our results not only explain the underlying physics of SEB, but also provide a way to tune and control the SEB performance.

We report the magnetocaloric effect in a Tb1-x Dy x Co2 compound which exhibits a wide working temperature window around the Curie temperature (T C) and delivers a large refrigerant capacity (RC) with near-zero thermal hysteresis. Specifically, the wide full width at half maxima ([Formula: see text]) can reach up to 62 K and the RC value changes from 216.5 to 274.3 J Kg-1 when the external magnetic field increases to 5 T. Such magnetocaloric effects are attributed to a magnetic and structural transition from a paramagnetic and cubic phase to a ferromagnetic (M S along [1 1 1] direction) and rhombohedral phase or ferromagnetic (M S along [0 0 1] direction) and tetragonal phase.

We report a magnetocaloric effect with nearly zero thermal hysteresis in Heusler alloy of Ni50Mn36Sb8Ga6 around room temperature due to a ferromagnetic transition in martensitic state (FTMS). The refrigerant capacity value of this ferromagnetic transition in the vicinity of onset temperature TCM can arrive at 163.8 J/kg, much higher than that of first-order magnetically martensitic transition in the same alloy. Such a magnetocaloric effect in FTMS is attributed to a second-order (or a weak first-order) transition from an antiferromagnetic phase with modulated 7 M orthorhombic structure to a ferromagnetic phase with modulated 4O orthorhombic structure.