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Inspired by the global budget concept in health care, we propose an innovative subsidy scheme in which governments do not commit the subsidy amount in advance but determine it by the end of the subsidy period. The performance of the traditional and proposed subsidy schemes is evaluated in an oligopoly without competition, where each manufacturer decides its product quality and production quantity under the diseconomies of scale in production. Both types of schemes can take into account product quality or not. Our results show that compared to the traditional scheme, the proposed scheme drives manufacturers to reduce production quantity but improves product quality and brings them higher profits. Furthermore, the scheme results in greater social welfare when the subsidy budget is large. Finally, we conduct robustness checking by considering the market competition and absence of the diseconomies of scale, respectively. The result shows that the main findings in the basic model continue to hold, while there are additional findings. In the first scenario, as the market competition intensity increases, our proposed scheme becomes more preferable to the manufacturers and the government. In the second scenario, subsidy schemes that take product quality into account are never preferable. [ABSTRACT FROM AUTHOR]

The micromorphology and composition of three pieces of ancient celadon with various degrees of corrosion salvaged from Dalian Island, Pingtan County of East China's Fujian Province were analyzed. The results indicate that there were black corrosion products with a high content of Fe and Mn and white crystals with high concentrations of Ca and Mg on the surfaces of the samples. The black corrosion products infiltrated into the interior along the cracks on the sample surfaces, producing corrosion products mainly composed of FeOOH and MnO2. Meanwhile, there were white crystals containing MgCa(CO3)2 gathering on the black corrosion surface. Subsequently, the attachment of a biological carbon film containing proteins and polysaccharides in the corrosion area was determined by Fourier transform infrared spectroscopy and steady state and transient fluorescence. It is speculated that the existence of a bio-film and the presence of Fe and Mn oxides is related to the microbial corrosion and mineralization of iron bacteria in the marine environment. In this paper, through the analysis of the corrosion products of the effluent celadons as well as the study of iron bacterial biological corrosion and biomineralization, the corrosion model is explained and established so as to clarify the microbial corrosion mechanism of celadon ceramics retrieved from the seabed. [ABSTRACT FROM AUTHOR]

Due to the simplicity and low cost of attribute inspection, several control charts have been proposed for employing attribute inspection to monitor the mean shifts. But these charts usually require a larger sample size to perform well as the X ¯ chart. In this paper, a new npCEV chart is proposed to monitor process mean shifts based on attribute inspection in which the conditional expected value (CEV) weight method is adopted to take full advantage of the censored observations obtained from attribute inspection. The optimal design of the proposed chart is derived from optimizing average run length (ARL) properties. Several numerical experiments are conducted to investigate the performance of the proposed chart. The results demonstrate that the proposed chart is always superior to npx chart by reducing the sample size by 70% to 97% while achieving the same ARL as npx chart. In addition, the proposed chart always achieves a smaller ARL1 than X ¯ rec chart. Furthermore, the proposed chart outperforms X ¯ chart as it achieves the same ARL as that of X ¯ chart with a lower inspection cost. Finally, an industry example is given to illustrate how to simply apply the proposed chart to the manufacturing process. [ABSTRACT FROM AUTHOR]

This retrospective study was performed to investigate the predictive power of the Ovarian Sensitivity Index (OSI) for IVF/ICSI outcomes in infertile patients who were of normal expected ovarian response. A total of 912 infertile patients who underwent GnRH antagonist protocol between January 2017 to August 2019 at the Medical Center for Human Reproduction, Beijing Chao-Yang Hospital were included. All patients completed the full oocyte retrieval cycle and either had a live birth or had no embryos left. OSI was significantly lower in patients with a live birth (196.0 ± 120.4 in the live birth group vs 276.4 ± 235.7 in the non-live birth group, p < 0.001) while follicular output rate (FORT, defined as the ratio of pre-ovulatory follicle count on hCG day x 100/small antral follicle count at baseline) showed no significant difference. Patients were divided into low, average and high OSI groups and analysed in tertiles. From the low to the high OSI group, the cumulative live birth rate (CLBR) decreased dramatically (72.7 vs 67.2 vs 54.8%, p < 0.001). Multivariate regression analysis showed that OSI was an independent factor affecting CLBR (OR: 0.996, 95%CI: 0.995–0.998, p < 0.001) in our study population. In conclusion, OSI can be used as an independent indicator to distinguish fecundity in infertile patients with normal expected ovarian response and is probably more sensitive than FORT. [ABSTRACT FROM AUTHOR]

We study a service market with two firms: one that provides regular and another that provides premium services. Customers are delay sensitive and heterogeneous in evaluating the service level. We study two competition games that differ in segmentation-marketing strategies. One is the size-based competition in which firms compete on the segment size dimension, and the other is the value-based competition in which firms compete on the segment target (regarding customer valuation) dimension. For both games, the Nash equilibrium always exists, and the (Pareto dominant) equilibrium is unique. Interestingly, the premium service provider's effective arrival rate can be increasing in its competitor's service rate in the value-based game. Moreover, we capture the conditions for the equilibrium market as either a monopoly or a duopoly and show that size-based competition helps sustain service variety. We also show that the prices are reduced in the value-based game; the premium (regular) service provider serves more (fewer) customers in the value-based game than in the size-based game. Our results show that value-based competition is more intensive in the sense that the number of customers who are served, customer surplus and social welfare are higher, while the total revenue of two firms is lower in the value-based competition than in the size-based competition. [ABSTRACT FROM AUTHOR]

Cap-and-trade systems, or emission trading systems (ETS), are increasingly adopted by countries and regions to provide economic incentives for reducing greenhouse gas emissions. The majority of existing ETS are early-stage systems implemented in and after 2013. These early-stage ETS are typically characterised by a focus on few industry sectors, and the employment of free emission allocation schemes including grandfathering and benchmarking. In this paper, we investigate the impact of emission allocation schemes in an early-stage cap-and-trade system in a duopoly market. We show that benchmarking scheme may lead the energy-efficient firm to reserve part of its emission permits, while firms always use up their after-trading permits under grandfathering. We also find that a more stringent emission cap may increase firms' profits rather than decreasing them under both allocation schemes, suggesting a possible cause for windfall profits observed in early-stage ETS. Benchmarking is found to lead to lower emissions compared to those under grandfathering, while it may result in higher or lower firm profits, consumer surplus, and the overall social welfare. Furthermore, under either allocation scheme, allowing emission trading does not affect the total emissions, while it can increase firm profits and consumer surplus and therefore the overall social welfare. [ABSTRACT FROM AUTHOR]

The aim of the study was to examine the clinical value of blastocysts derived from mono-pronuclear (1PN) or non-pronuclear (0PN) zygotes with two polar bodies (2PB), which were selected by our criteria. We retrospectively analysed 610 frozen-thawed blastocyst transfer (FET) cycles and the corresponding oocyte retrieval cycles from 2014 to 2017. Developmental potential and clinical outcomes of embryos derived from zygotes with various numbers of pronuclei were analysed. Based on more detailed pre-selection settings, blastulation rates of 1PN/2PB and 0PN/2PB-derived embryos were 70.18% and 69.17%, respectively. Blastocyst FET results were not significantly different between 2PN/2PB, 1PN/2PB and 0PN/2PB groups in terms of clinical pregnancy rates (59.79%, 47.06% and 56.25%), implantation rates (47.24%, 40.00% and 47.62%), live birth rates (49.39%, 29.41% and 43.75%) or malformation rates (0%, 0% and 0%). In conclusion, after strict morphological selection and blastocyst culture, 1PN/2PB and 0PN/2PB-derived embryos in IVF cycles can have considerable clinical value. Blastocysts derived from 1PN/2PB or 0PN/2PB zygotes are worthwhile FET option for patients who have no available 2PN-derived embryos. [ABSTRACT FROM AUTHOR]

Aim: COVID-19 is a major threat to public health worldwide. A large proportion of COVID-19 patients is proved to develop anemia. Herein, we investigate the association between anemia and severe pneumonia. Materials & methods: 137 of COVID-19-confirmed patients admitted to Wuhan Union Hospital (Wuhan, China) from 13 February to 17 March 2020 were included. Their clinical characteristics and laboratory data were studied, and multivariable logistic regression analyses were performed. Results: The anemic patients were less likely to develop fever in the early stage of COVID-19. Elevated IL-6 levels were found in anemic COVID-19 patients compared with those without anemia. COVID-19 patients with anemia had an 8.2 times greater possibility of developing severe pneumonia compared with their counterparts without anemia. Conclusion: This study comprehensively describes the clinical characteristics of anemic patients with ordinary, severe and critical COVID-19 and demonstrates the close relationship between the anemia and severe COVID-19. [ABSTRACT FROM AUTHOR]

The purpose of this study was to explore the application of glucose to improve embryo development potential when fertilization is delayed in mice. After recovery, mouse oocytes were cultured alone for 6 h before fertilization in three fertilization media: G-IVF PLUS, G-IVF PLUS with 5 mM and 10 mM glucose. G-IVF PLUS group was used as the control group. Then, in vitro fertilization (IVF) was performed and blastocysts were transferred at Day 4. To compare the effects of different glucose concentrations on embryo development and birth outcomes, conventional IVF and embryo transfer were carried out in G-IVF PLUS, G-IVF PLUS with 5 mM and 10 mM glucose. The results indicated that G-IVF PLUS with 5 mM glucose significantly increased blastocyst rate (p < 0.05) and birth rate (p < 0.05) when fertilization was delayed 6 h compared with G-IVF PLUS groups. In conventional IVF without delayed fertilization, embryo development was not significantly affected by G-IVF PLUS with 5 mM or 10 mM glucose. There were no significant differences in terms of birth rate, fetal weight, crown-rump length, tail length and birth defect rate among the three groups. In conclusion, 5 mM glucose could significantly improve embryo developmental potential and birth outcomes when fertilization was delayed 6 h and did not have adverse effects on embryo quality and birth outcomes for normal IVF. It might have a good prospect of clinical application in assisted reproductive technology (ART). Abbreviations: ART: assisted reproductive technology; IVF: in vitro fertilization; ICSI: intracytoplasmic sperm injection; TFF: total fertilization failure; TESA: testicular sperm aspiration. [ABSTRACT FROM AUTHOR]

Between 5 and 25% of patients with cutaneous lupus erythematosus (CLE) can progress to systemic lupus erythematosus (SLE) during the course of the disease. There is no clear predictive guideline for the progression of CLE to SLE. Lupus erythematosus (LE), a chronic autoimmune disease, has a wide spectrum of manifestations. On one side of the spectrum is CLE, in which patients only display skin lesions. On the other side of the spectrum is SLE, which develops severe systemic involvement. CLE has even been considered as a separate entity from LE, while CLE is also proposed to be associated with SLE. In this review, the authors will describe the relationship between CLE and SLE; summarize the incidence, risk factors, systemic involvement, and management of patients who transition to SLE. The literature search was conducted mainly through PubMed from March to July 2020. The identification of clinical characteristics and biomarkers in patients facing risk of developing SLE and monitoring the disease on a regular basis are essential to promptly manage and hopefully prevent transition to the systemic form. [ABSTRACT FROM AUTHOR]

This study aimed to explore the effects of low-concentration (0.6 ng/mL) granulocyte-macrophage colony-stimulating factor (GM-CSF) supplementation on human embryo quality and pregnancy outcomes in patients with fresh transfer cycles. The data were retrospectively collected from 719 hyperstimulation cycles of 631 patients divided into two groups: GM-CSF supplementation (0.6 ng/mL, n = 399) and control (n = 320). The embryo quality and pregnancy outcomes were compared. GM-CSF addition significantly increased the available embryo rate (52.0 vs. 48.1%, p < .05). In patients >38 years, it significantly enhanced cleavage (99.4 vs. 97.8%, p < .05) and blastocyst formation (45.7 vs. 34.9%, p < .05) rates but not pregnancy outcomes, including clinical pregnancy (power = 0.160) and implantation (power = 0.204) rates. The lack of a statistically significant difference could be related to low study power. These results suggest that low-concentration GM-CSF addition contributes to embryo quality improvement, especially in patients >38 years.IMPACT STATEMENTWhat is already known on this subject? Granulocyte-macrophage colony-stimulating factor (GM-CSF) has a beneficial effect on the development of human embryos in assisted reproductive technology.What do the results of this study add? Adding 0.6 ng/mL GM-CSF significantly increased the available embryo rate. In patients over 38 years of age, it statistically significantly enhanced the cleavage rate (99.4 vs. 97.8%, p < .05) and blastocyst formation rate (45.7 vs. 34.9%, p < .05).What are the implications of these findings for clinical practice and/or further research? GM-CSF benefits embryos with poorer development potential and a randomised clinical trial with a larger sample size should be performed. [ABSTRACT FROM AUTHOR]

In this paper, a synthetic control chart is proposed by integrating the salient features of the npx chart and the CRL chart. The synthetic chart achieves higher detection effectiveness on both small and large mean shifts while retaining the operational simplicity of the attribute charts owing to only using attribute inspection. Both statistical and economic design of the synthetic chart are considered and numerical tests have indicated that the synthetic chart has a higher power for detecting mean shifts than the npx chart, MON chart and CUSUM chart. In addition, sensitivity analyses are also performed under both the statistical and economic design model. [ABSTRACT FROM AUTHOR]

The wooden construction painting is a type of an ancient decorative art on Chinese ancient structures. Comprehensive reports concerning the composition of these materials are rather limited. Here multiple analytical methods were applied to systematically explore the morphology and materials. Several paintings were characterized using a morphological microscope. Scanning electron microscopy–energy dispersive spectrometry (SEM-EDS), X-ray fluorescence (XRF), and X-ray diffraction (XRD) detected emerald green and ultramarine in the paint layers. Gas chromatography–mass spectrometry (GC-MS) indicated that the binding medium in the first layer was composed of blood. Our study helps to comprehensively understand the preparation of the wooden construction paintings in the renowned Summer Palace and provide a scientific basis for its restoration and related archeology work. [ABSTRACT FROM AUTHOR]

Control chart and maintenance management (MM) are two key tools in production management. Although there is a close connection between these tools, they are usually studied separately in both academia and industry. This article develops an integrated model of MM and quality control policy with an adaptive synthetic chart. The corrective maintenance and preventive maintenance are considered. An economical design model that minimizes the general cost of implementing the integrated model is established and solved by a specific genetic algorithm. Numerical experiments are conducted to analyze the optimal policy. The results show that an economic benefit of 2.64% is obtained by the joint optimization model. Finally, the effects of model parameters on the optimal policies are presented through sensitivity analysis, with practical implications for practitioners. [ABSTRACT FROM AUTHOR]

This study uses national time-series survey data to monitor the levels and changing trends of doctoral student satisfaction with their education process. From 2012 to 2016, advising ranked highest on the satisfaction continuum, followed by scientific research training, curriculum and teaching, the financial aid system, and management and service. The latter three indicators show the most significant weaknesses, albeit with a steady upward trend, and therefore require stronger reforms and pinpointed policy implementation. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the efficacy of different open cryo-carriers: the CryoloopTM, CryotopTM, and CryoleafTM, in embryo survival and clinical outcome in patients with frozen embryo transfer (FET) cycle. We analyzed the embryo survival rate and clinical outcome in 325 patients of 348 FET cycles vitrified with the CryoloopTM (160 cycles), CryotopTM (105 cycles), or CryoleafTM (83 cycles). No significant differences were observed in embryo survival rate (98.8% vs. 100% vs. 97.7%, p > 0.05), HCG positive rate (58.8% vs. 63.8% vs. 57.8%, p > 0.05), biochemical pregnancy rate (6.9% vs. 11.4% vs. 9.6%, p > 0.05), or implantation rate (33.2% vs. 37.4% vs. 34.1%, p > 0.05) in the three groups respectively. The early abortion rate of the CryoloopTM group was significantly higher than that of the CryotopTM and CryoleafTM group (27.1% vs. 3.6% and 7.5%, p < 0.05). At the same time, the average female age of the CryoloopTM group was significantly older by 1 year than that of the CryotopTM and CryoleafTM group (33.29 ± 4.71 years vs. 31.96 ± 4.27 years and 31.1 ± 4.28 years, p < 0.05). There was no significant difference in take home baby rate (38.1% vs. 46.7% vs. 43.4, p > 0.05) or birth weight among the groups (2893.5 ± 780.8 g vs. 2778.4 ± 710.0 g vs. 2724.5 ± 838.8 g, p > 0.05). No case of neonatal malformation was observed in the present study. Overall, CryotopTM and CryoleafTM were effective for embryo vitrification at both the cleavage and blastocyst stage according to the results of clinical outcome and infant characteristics. However, CryoloopTM led to a decreased positive HCG rate and increased early abortion rate, heightened at the cleavage stage.Abbreviations: LN2: liquid nitrogen; CPA: cryoprotectant; ART: assisted reproductive technology; IVF: in vitro fertilization; ICSI: intracytoplasmic sperm injection; BMI: body mass index; FSH: follicular stimulation hormone; COH: controlled ovarian hyperstimulation; FET: frozen embryo transfer; mm: millimeter; HCG: human chorionic gonadotropin; RCT: randomized clinical trial; NC: natural cycle; AC: artificial cycle; EM: equilibration medium; DMSO: dimethyl sulphoxide; EG: ethylene glycol; VM: vitrification medium; WM: warming medium [ABSTRACT FROM AUTHOR]

Although the classical Shewhart np control chart has been widely used to detect an out-of-control status of manufacturing process, it is static and there is lack of responsiveness to slight process changes. In this paper, an adaptive np control chart with a joint sampling strategy combining double sampling (DS) and variable sampling interval (VSI) is developed. The multiple dependent state sampling scheme is adopted to further improve the performance of the control chart. An economical design model to minimize the general cost of using the proposed chart is established and solved by a genetic algorithm. The numerical results show that comparing to traditional static np control chart, the proposed np chart yields better performance in terms of shorter time to signal an out-of-control process and less expected cost per unit of time. Comparisons are made to show the capability of the proposed chart in yielding average reductions of 5.01% and 8.89%, in the cost of the proposed model compared to situations in which either the DSVSI np chart or the traditional np chart is used. [ABSTRACT FROM AUTHOR]

Development of an effective system for oocyte-cryopreservation is of clinical relevance in reproductive medicine. However, oocyte-preservation is not as effective as embryo preservation. In this study, we used a 37°C pre-equilibrium temperature as part of a modified vitrification method for human oocyte cryopreservation. The effect of the new method on spindle configuration, chromosomal arrangement, and mitochondrial distribution was investigated inin vitro-matured human oocytes. A total of 101in vitro-matured oocytes were randomly assigned for vitrification at pre-equilibrium temperature of 37°C (37°C Group,n=50) or at room temperature (RT Group, 22-24°C,n=51). The time needed for vitrification in the 37°C group was significantly shorter than that in the RT group. Defective spindles were found in 45.5% and 69.0% oocytes in the 37°C group and RT group, respectively (p< 0.05). Abnormal chromosomes were found in 47.7% and 71.4% oocytes, respectively (p< 0.05). There were no significant differences with respect to oocyte survival rate and mitochondrial distribution pattern between the two groups. These results indicate that vitrification at a pre-equilibrium temperature of 37°C may reduce the incidence of defective spindle configuration and chromosomal abnormalities inin-vitro-matured human oocytes. Abbreviations: ICSI: intracytoplasmic sperm injection; FSH: follicle-stimulating hormone; MII: metaphase II; EG: ethylene glycol; PROH: 1,2-propanediol [ABSTRACT FROM PUBLISHER]

AbstractWe investigate a supply chain consisting of a supplier and an e-commence platform who sign a consignment contract with uncertainty in price, demand, and yield. Due to the challenges of actually determining the joint distribution of random variables, we assume that only the partial distributional information is available for these three uncertainties. To address the issue of distributional ambiguity and to more accurately account for arbitrary correlations among these uncertainties, we introduce a moment-based distributionally robust optimization (DRO) approach that assumes only the first and second moments of these three uncertainties are known. Given an exogenous consignment rate, we derive the closed-form expression for the supplier’s optimal production decision and her worst-case expected profit. We study the impact of random price and random yield within the ambiguity set on the supplier’s production decision and the worst-case expected profit. From the e-commerce platform’s perspective, we further examine the contract design problem when the consignment rate is endogenous and analyze equilibrium solutions for both contracting parties. Our results show that the additional consideration of price or yield uncertainty within the ambiguity set does not always mitigate or enhance the degree of conservatism of the contracting parties, which is closely related to the correlation between any two types of uncertainty, as well as the degree of uncertainty itself. [ABSTRACT FROM AUTHOR]