In a product market with uncertain demand, we examine a distribution channel consisting of one manufacturer and one capital-constrained retailer. The retailer may fund its business by borrowing ...credit either from a competitive bank market or from the manufacturer, provided it is also to the latter׳s benefit to extend trade credit. Under bank credit financing, we show that the channel behaves as if the retailer is not constrained by capital. In a wholesale price contract, we find that trade credit makes both channel members better off and is the unique financing equilibrium; trade credit better integrates the channel than bank credit by centralizing the financing of distribution at the manufacturer. We further compare bank versus trade credit under a classical channel contract, revenue sharing contract. In addition, we present a set of numerical experiments to show how product cost, internal capital, and demand variability impact on the market equilibrium under both bank and trade credits.
► We study the value of 3PL firms in budget-constrained supply chains. ► 3PL firms can help reduce asymmetric information disadvantages. ► Players’ profits are improved when 3PL financing the ...budget-constrained retailer. ► All players can be better off under 3PL financing than under bank financing. ► 3PL financing conditionally outperforms supplier financing.
Integrated logistics and financial services have been practiced by third party logistics (3PL) firms for years; however, the literature has been silent on the value of 3PL firms as credit providers in budget-constrained supply chains. This paper investigates an extended supply chain model with a supplier, a budget-constrained retailer, a bank, and a 3PL firm, in which the retailer has insufficient initial budget and may borrow or obtain trade credit from either a bank (traditional role) or a 3PL firm (control role). Our analysis indicates that the control role model yields higher profits not only for the 3PL firm but also for the supplier, the retailer, and the entire supply chain. In comparison with a supplier credit model where the supplier provides the trade credit, the control role model yields a better performance for the supply chain as long as the 3PL firm’s marginal profit is greater than that of the supplier. We further demonstrate that, for all players, both the control role and supplier credit models can outperform the classic newsvendor model without budget constraint.
•PFAS mixture was inversely associated with E2 and E2/TT in young men, with PFuDA being the major contributor.•Exposure to PFTrDA and PFDoA were associated with reduced INSL3 levels.•No consistent ...associations were found between branched PFAS isomers and F-53B and male reproductive hormones.
Previous epidemiological studies on the relationship between per- and polyfluoroalkyl substances (PFAS) exposure and male reproductive hormones were mainly limited to a few legacy PFAS and ignored the possible mixture effects.
To assess the associations of PFAS mixture, branched isomers and emerging alternatives of PFAS with male reproductive hormones.
A total of 902 men (mean age: 31.3 years) were recruited in this cross-sectional study. We quantified 24 targeted PFAS, including 7 branched PFOS isomers, 2 branched PFOA isomers and 2 components of F-53B, in blood plasma. Five reproductive hormones, including total testosterone (TT), estradiol (E2), follicular stimulating hormone (FSH), luteinizing hormone (LH) and insulin like factor 3 (INSL3), and sex hormone binding globulin (SHBG) were measured in serum. Associations were first assessed by confounder-adjusted multiple linear regression while correcting for multiple comparisons. Bayesian kernel machine regression (BKMR) and adaptive elastic net (AENET) were further used to assess mixture effects and the adjusted exposure response (ER) relationship of individual PFAS.
After adjusting for confounders, we found that PFAS mixture was significantly and inversely associated with E2 and E2/TT, with perfluoro-n-undecanoic acid (PFuDA) being the major contributor. Although the associations between PFAS mixture and other hormones were non-significant, certain individual PFAS presented significant associations. Notably, perfluoro-n-tridecanoic acid (PFTrDA) and perfluoro-n-dodecanoic acid (PFDoA) were found to be significantly and inversely associated with INSL3, a unique indicator of Leydig cells function. Meanwhile, significant positive associations were found between perfluorobutane sulfonic acid (PFBS) and FSH and between PFuDA and LH. But the associations with branched isomers or F-53B were sporadic and inconsistent.
Our findings provided the evidence that PFAS mixture may reduce E2 level, and certain PFAS (i.e., PFTrDA and PFDoA) may have negative effects on Leydig cells function among young men. Additional studies are much needed to confirm our results and elucidate potential mechanisms.
•Magnetic porous carbon derived from bimetallic metal–organic framework was synthesized.•The magnetic porous carbon was used as sorbent for MSPE of organochlorine pesticides from drinking and ...environmental water samples.•High extraction efficiency and good sensitivity was achieved using the developed method.
In this work, magnetic porous carbon material derived from a bimetallic metal–organic framework was explored as an adsorbent for magnetic solid-phase extraction of organochlorine pesticides (OCPs). The synthesized porous carbon possessed a high specific surface area and magnetization saturation. The OCPs in the samples were quantified using gas chromatography coupled with a triple quadrupole mass spectrometer. The experimental parameters, including the desorption solvent and conditions, amount of adsorbent, extraction time, extraction temperature, and ionic strength of the solution, were optimized. Under optimal conditions, the developed method displayed good linearity (r>0.99) within the concentration range of 2–500ngL−1. Low limits of detection (0.39–0.70ngL−1, signal-to-noise ratio=3:1) and limits of quantification (1.45–2.0ngL−1, signal-to-noise ratio=10:1) as well as good precision (relative standard deviation<10%) were also obtained. The developed method was applied in the analysis of OCPs in drinking and environmental water samples.
Ambient measurements of PM2.5-bounded polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs (NPAHs), and oxy-PAHs (OPAHs) were conducted during the summer in Jinan, China, an urban site, and at Tuoji ...island and Mt. Tai, two background locations. 3.5 h and 11.5 h sampling intervals in daytime and nighttime were utilized to research the diurnal variations of PAHs, NPAHs, and OPAHs. The concentrations of PAHs, NPAHs, and OPAHs were highest at the urban site and lowest at the marine site. The diurnal patterns of PAHs and NPAHs at the urban and marine sites were dissimilar to those observed at the mountain site partly due to the influence of the boundary layer. Vehicle emissions at the urban site made a large contribution to high molecular weight PAHs. 1N-PYR and 7N-BaA during morning and night sampling periods in JN were relatively high. Fossil fuel combustion and biomass burning were the main sources for all three sites during the sampling periods. The air masses at the marine and mountain sites were strongly impacted by photo-degradation, and the air masses at the marine site were the most aged. Secondary formation of NPAHs was mainly initiated by OH radicals at all the three sites and was strongest at the marine site. Secondary formation was most efficient during the daytime at the urban and mountain sites and during morning periods at the marine site. The average excess cancer risk from inhalation (ECR) for 70 years' life span at the urban site was much higher than those calculated for the background sites.
•Diurnal variations of NPAHs and OPAHs were analyzed at urban and background sites.•The air masses collected at the marine site was the most aged.•Fossil fuel combustion and biomass burning were the main sources.•The secondary formation of NPAHs at urban site was strongest during the daytime.•The excess cancer risk in Jinan was higher than those in the background sites.
We propose a novel filter circuit that incorporates a double ring resonator with a balanced Mach-Zehnder interferometer (MZI). The circuit has a response equivalent to a conventional ring loaded MZI ...filter, but with added flexibility in terms of configurability. The second-order filter can also be cascaded to realize higher-order filters. The circuit incorporates a two-stage input and output coupler to further reduce the effect of dispersion. A combination of local and global optimization strategies to program the filter, using tailored objective functions, have been tested in simulation and experiments. To our best knowledge, this is the first time a global optimization strategy is directly used in ARMA filter synthesis and simulation without any additional requirement. We further extend the optimization strategy into experiments and demonstrated its use in practical case for programmable filter circuits.
An easy prepared probe, BHMMP, was designed and synthesized, which displayed a significant fluorescence enhancement (over 38-fold) and obvious color change in the recognition of Al3+. The binding ...ratio of probe BHMMP to Al3+ was determined as 1:1, according to Job plot. The binding mechanism was fully clarified by the experiments, such as FT-IR spectrum, ESI–MS analysis, and 1H NMR titration. A DFT study further confirmed the binding mode of BHMMP to Al3+. The limit of detection (LOD) for Al3+ was determined as low as 0.70 µM, based on the fluorescence titration of BHMMP. Moreover, the results from real sample experiments, including real water samples, test papers, and cell images, well-demonstrated that BHMMP was capable of sensing Al3+ in environmental and biological systems.
•Magnetic microspheres containing a SiO2-protected Fe3O4 core, a layer of MOF and TiO2 shell were synthesized.•The microspheres were used as sorbents for MSPE of fungicides from water samples.•High ...extraction efficiency and sensitivity were achieved using the developed method.
In this work, a core-shell Fe3O4@SiO2@MOF/TiO2 nanocomposite was synthesized and used to as adsorbent for magnetic solid-phase extraction (MSPE) of triazole fungicides from environmental water samples. Five triazole fungicides, namely, triadimenol, hexaconazole, diniconazole, myclobutanil, and tebuconazole, were selected as target analytes for MSPE. These analytes were quantitatively adsorbed on microspheres, and the sorbents were separated from the solution by using a magnet. The analytes were desorbed by methanol and determined through liquid-chromatography coupled with tandem mass spectrometry. The extraction parameters affecting the extraction efficiency were optimized through response surface methodology. The limits of detection and limits of quantification for the selected fungicides were 0.19–1.20ngL−1 and 0.61–3.62ngL−1, respectively. The proposed method was applied to determine the concentration of fungicides in actual environmental water samples. The accuracy of the proposed method was evaluated by measuring the recovery of the spiked samples. The satisfying recoveries of the four water samples ranged from 90.2% to 104.2%. Therefore, the magnetic metal–organic framework/TiO2 nanocomposite based MSPE is a potential approach to analyze fungicides in actual water samples.
China is the largest chlorinated paraffin (CP) producer in the world. Given that CP production is a major source of short-chain CP (SCCP) pollution in China, the effects of CP production on the ...environment inside and outside of CP production plants are worth revealing. The concentrations and specific congener group patterns of SCCPs in various environmental matrices, such as air, soil and dust, inside and outside of a chosen CP production plant surrounded by farmlands and villages were analyzed to explore SCCP pollution and transportation behaviors. SCCP concentrations in air (129–1442 ng/m3) and soil (28–554 μg/g) samples inside the CP production plant were dramatically higher than those in air (91–333 ng/m3) and soil (102–441 ng/g) samples outside the CP production plant. Based on the congener abundance patterns among these samples, lighter groups (C10-11 and Cl5-6) were dominant in atmospheric environment, with greater long-range transport potential, whereas heavier groups (C12-13 and Cl7-10) were inclined toward deposition. It was clear that substantial amounts of SCCPs were released from the CP production plant, which contaminated the environment inside and outside of the plant. The daily occupational SCCP exposure of employees in the production hall (21.8 μg/day-kg) exceeded the tolerable daily intake (TDI, 10 μg/day-kg) given by Canadian Environmental Protection Act, suggesting that production employees were confronted with high health risk from SCCP exposure; while daily SCCP exposure of employees in office areas (0.57 μg/day-kg) and residents near the CP plant (1.22–25.5 × 10−2 μg/day-kg) were significantly lower, representing low health risk.
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•The environmental impacts and health risks of a CP production plant were assessed.•Massive in-plant SCCPs were from CP production and accidental leakage.•Out-plant SCCPs mainly resulted from atmospheric transport, imposing low health risk.•Lighter congeners were more diffusive; heavier congeners tended to deposition.•SCCPs in the production hall potentially imposed health risk to employees.
Rhizoma Bolbostemmatis, the dry tuber of
, has being used for the treatment of acute mastitis and tumors in traditional Chinese medicine. In this study, tubeimoside (TBM) I, II, and III from this ...drug were investigated for the adjuvant activities, structure-activity relationships (SAR), and mechanisms of action. Three TBMs significantly boosted the antigen-specific humoral and cellular immune responses and elicited both Th1/Th2 and Tc1/Tc2 responses towards ovalbumin (OVA) in mice. TBM I also remarkably facilitated mRNA and protein expression of various chemokines and cytokines in the local muscle tissues. Flow cytometry revealed that TBM I promoted the recruitment and antigen uptake of immune cells in the injected muscles, and augmented the migration and antigen transport of immune cells to the draining lymph nodes. Gene expression microarray analysis manifested that TBM I modulated immune, chemotaxis, and inflammation-related genes. The integrated analysis of network pharmacology, transcriptomics, and molecular docking predicted that TBM I exerted adjuvant activity by interaction with SYK and LYN. Further investigation verified that SYK-STAT3 signaling axis was involved in the TBM I-induced inflammatory response in the C2C12 cells. Our results for the first time demonstrated that TBMs might be promising vaccine adjuvant candidates and exert the adjuvant activity through mediating the local immune microenvironment. SAR information contributes to developing the semisynthetic saponin derivatives with adjuvant activities.
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