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After consideration of a supply chain consisting of a manufacturer and a retailer, this paper uses a two-stage Stackelberg game to explore the production decision as well as the government cap setting with wholesale price and revenue sharing contracts under cap-and-trade regulation. We also compare the total carbon emission and social welfare with the two contracts. We list some main conclusions. Firstly, we find that the government's over-allocated carbon credits may damage the manufacturer's profit with wholesale price or revenue sharing contract, which can increase the difficulty of implementing cap-and-trade regulation. Secondly, we detect that the optimal cap under the two contracts is decreasing or constant in the environmental concern parameter, which means that the government should keep the optimal cap unchanged under the low or high environmental concern parameter, and decrease the cap when the middle environmental concern parameter increases. Thirdly, we show that using green technology may increase the total carbon emission. Finally, we discover that the social welfare with wholesale price contract is less (larger) than that with revenue sharing contract under low (high) value of the environmental concern parameter, and the social welfare with the two contracts is equal to each other under middle value of the environmental concern parameter. [ABSTRACT FROM AUTHOR]

Purpose: Neutrophils remain at the top of congenital and adaptive immune systems. The past 20 years witnessed a steep rise in the interest in neutrophil extracellular traps (NETs), which are a novel type of anti-pathogen mechanism coordinated with neutrophils. However, accumulating data revealed that excessive NETs in the host were associated with exacerbated inflammation, thrombosis, and autoimmunity. Increasing evidence found the participation of NETs in the pathophysiological process of many infectious and sterile diseases in the ocular system. Therefore, we discussed the role of neutrophil extracellular traps in the ocular system in this review. Methods: Articles were searched on PubMed, Embase and Web of science up to December 2021. Results: In this review, we exhibited the protective role of neutrophils patrolling the ocular surface from invading pathogens and their contribution to exacerbated inflammation and thrombogenesis in some ocular diseases. We also discussed the physiological and pathological processes of NET generation to identify novel biomarkers and therapeutic targets to interrupt immoderate NET formation and alleviate NET-induced harmful effects. Conclusions: Neutrophils and NETs are quite important for immune responses in the ocular system, while their negative effects on ocular tissue should also be emphasized, which could serve as novel biomarkers and potential therapeutic targets. [ABSTRACT FROM AUTHOR]

We look at a Bertrand model in which each firm may be unreliable with random yield, so the total quantity brought into market is uncertain. Under mild conditions, the Bertrand model with random yield has a unique Nash equilibrium, in which the prices and production quantities are determined by each firm’s production cost and reliability. In the case of symmetric firms, we compare Bertrand competition with Cournot competition by numerical examples, and find that Bertrand competition yields lower prices and less profits than Cournot competition. Furthermore, in the case of symmetric firms with 0–1 yields, we explicitly show that Bertrand competition yields lower prices and less profits than Cournot competition, and the comparison between the quantities of Bertrand and Cournot competition is dependent on the value of reliability. When the reliability is high, Cournot competition yields less quantities than Bertrand competition. Otherwise, the other hand holds. [ABSTRACT FROM AUTHOR]

We study a newsvendor problem with capital constraint and demand forecast update. The newsvendor has two instants to order from a supplier prior to a single selling season. While the demand is uncertain, the newsvendor can improve the forecast by utilizing the market signal observed between the first and second instants. We analyze the newsvendor’s optimal ordering policy in two cases: risk-neutrality and risk-aversion. Our analysis suggests that the optimal policy in each case is characterized by a critical value: a target safety capital. Under this policy, part of capital is left to use at instant 2 if and only if the initial capital is above the target safety capital. When this happens, the order quantity at instant 1 decreases as the initial capital increases. We further analyze the effect of information update on the newsvendor’s ordering policy. Our results indicate that more capital should be left to use at instant 2 when the correlation coefficient between market information and demand becomes large or when the newsvendor is more risk-averse. [ABSTRACT FROM PUBLISHER]

Heavy metal contamination of agricultural soil has become a critical issue worldwide. A sustainable approach to mitigate heavy metal contamination is extremely important. Phytoremediation has been proved to be a well alternative for soil remediation as cost-effective, environment friendly, and esthetically pleasing. This review briefly elucidates heavy metal tolerance, uptake, and the corresponding mechanism in cotton, and discusses the risk of heavy metal residues and the socioeconomic benefits, to further assess cotton planting for phytoremediation of heavy metal-contaminated soils. Cotton plant has a relatively large biomass, a profuse toot system, and exhibits very excellent tolerance and enrichment capacity of heavy metals. Heavy metals residue in cotton was low. Especially, the content of heavy metal in the fiber, the main product of cotton, is obviously negligible. In brief, cotton as a fiber crop can be a promising candidate for phytoremediation of contaminated soils with heavy metals, which could minimize the risk of human food chain contamination and benefit in ecological and socioeconomic terms. [ABSTRACT FROM AUTHOR]

Soil heavy metal pollution has become a worldwide environmental issue that has attracted considerable public attention, largely from the increasing concern for the security of agricultural products. Heavy metals refer to some metals and metalloids possessing biological toxicity, such as cadmium, mercury, arsenic, lead, and chromium. These elements enter the soil agro-ecosystem through natural processes derived from parent materials, and through anthropogenic activities. Heavy metal pollution poses a great threat to the health and well-being of organisms and human beings due to potential accumulation risk through the food chain. Remediation using chemical, physical, and biological methods has been adopted to solve the problem. Phytoremediation has proven to be a promising alternative to conventional approaches as it is cost effective, environmentally friendly, and aesthetically pleasing. To date, based on the natural ability of extraction, approximately 500 taxa have been identified as hyperaccumulators of one or more metals. In addition, further research integrating biotechnological approaches with comprehensive multidisciplinary research is needed to improve plant tolerance and reduce the accumulation of toxic metals in soils. This review discusses harmful effects, sources of heavy metals, and the remediation technologies for soil contaminated by heavy metals. [ABSTRACT FROM AUTHOR]

Stinky mandarin fish is a nutritious fermented dish widely consumed in China. We evaluated changes in mandarin fish’ (Siniperca chuatsi) moisture and texture during fermentation to determine why the dish has a unique flavor. The moisture content was analyzed by the direct drying method and low-field nuclear magnetic resonance. Change in the hardness, chewiness, resilience, elasticity, gumminess, and adhesiveness of the meat was measured using a texture analyzer, and all improved gradually during fermentation. The moisture content decreased from 77.72% to 55.50%, water-holding capacity increased from 85.63% to 98.81%, and cooking loss decreased and then increased. Bound water and intermediate water content changed little, whereas free water content decreased significantly and intercellular binding increased. [ABSTRACT FROM AUTHOR]

Background: Cockayne syndrome is a rare, autosomal recessive, multisystem disorder that causes a senile appearance. Ophthalmic abnormalities are frequently present. Here, we report a wide range of ocular findings in a child with Cockayne syndrome. Materials and methods: The systemic and ocular findings were reviewed. A mutation analysis was performed in the patient and her parents. Results: The patient underwent a complete ocular examination. Both eyes had low visual acuity, corneal epithelial degeneration, punctate opacities of the lens, and retina disorders. The systemic findings included growth deficiency and a senile appearance. Gene analysis showed mutations in exons 4 and 18 of theERCC6gene. Conclusion: Multiple ocular abnormalities were observed in a patient with Cockayne syndrome. A detailed ophthalmic evaluation of children with Cockayne syndrome is advised. [ABSTRACT FROM AUTHOR]

Using a simple one-period model of a supply chain with one retailer and multiple risky suppliers, this paper studies questions of supplier selection and ordering policies among firms. A supplier is said to be unreliable when the quantity of goods effectively delivered by that supplier cannot correspond exactly to the order quantity. The question facing the retailer is to determine how many suppliers to contract and how much to order from each contracted supplier. We not only present the structural properties of the optimal ordering policy, but also analyze the effect of random yield and fixed ordering cost on the optimal policy and the retailer’s profit. [ABSTRACT FROM PUBLISHER]

This article considers the problem of joint replenishment and pricing decisions for a single product with fixed ordering costs and random supply in a fluctuated environment. We assume that the environment comprises a Markov chain with finite states and all the parameters are dependent on the environment states, such as supply, demand, and cost structure. Our objective is to maximize the total expected profit during the whole sales horizon by choosing an appropriate replenishment and pricing policy. We show that the form of the optimal ordering and pricing policy has an environment-dependent (s, S, p)-type. Moreover, we analyze the operational effects of random supply on the optimal policy and obtain that the optimal profit increases with the probability of receiving orders. The optimal profit function for the finite horizon problem converges to that for the infinite horizon problem under some mild conditions. [ABSTRACT FROM AUTHOR]

In this article, we consider an economic order quantity (EOQ) model with multiple suppliers and random yield. We show that the structure of the optimal ordering policy is not only dependent on the structure of setup cost but also on the distributions of random yield. For some particular cases of random yield, the optimal order quantity from each supplier can be formulated as an explicit form. [ABSTRACT FROM AUTHOR]