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Dissociation of biomolecules by tandem mass spectrometry (MS/MS) generates a variety of fragment ions which provide useful information for the structural characterization of biomolecules. Different fragmentation strategies result in different mass spectra for the same molecule and thus provide distinct features. Charge carriers play important roles in determining the dissociation pathways of the target precursor ions. The use of various transition metals ions as charge carriers of glycopeptide and glycan might provide additional structural information and needs to be investigated.A 9.4 T SolariX FTICR mass spectrometer was used for collision-induced dissociation (CID) of glycopeptide and glycan. Group IIB metal ions, including ZnFor ZnZn

Aluminum dust explosion venting experiments with static activation pressure ranging from 70 kPa to 280 kPa were conducted in the 20 L spherical chamber with venting diameters from 20 mm to 125 mm. For the case of high activation pressure, the maximum flame length in experiments is 1.64 m, which is close to the prediction of standard, while the maximum width is significantly smaller than the prediction. New fitting formulas in a laboratory scale for flame length and width are obtained, which provide a reference for venting safety area design, and the effect of activation pressure, dust concentration and venting area are taken into account. By the comparison, the external pressure prediction of EN14491 shows a good performance and NFPA68 has an opposite trend with experiments. Based on the experimental results, it is found that the the external pressure attenuation is inversely proportional to the distance, which is different with the coefficient of the distance suggested by the standard EN 14491.

Two risk control mechanisms, namely, cash deposit, and loan limits based on retained profit or maximum expected guarantor profit, are developed for capital-constrained newsvendor financing. Results show that with a large initial capital or mortgage asset, the newsvendor reduces the order quantity to avoid bankruptcy risk. Under the risk control mechanism with a cash deposit, the guarantor gains greater profit when the newsvendor has a low initial capital. Setting a loan limit is thus an effective mechanism for newsvendors to not only reduce the bankruptcy risk, but also increase the guarantee profit. Numerical experiments also show that, compared with the risk control mechanism based on maximum expected profit, loan limits based on retained profit is more beneficial for the newsvendor, guarantee, and the bank.

Dietary intake is one of the main pathways for residents to become exposed to chlorinated paraffins (CPs). In China, due to the popularization of nutritional and medicinal edible fungi, consumption has increased on a yearly basis. Edible fungi have a variety of active substances and are consumed daily by residents. However, there is limited information on the concentration and source of chlorinated paraffins in edible fungi. In this study, the concentrations of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) in 105 edible fungi samples and 36 culture material samples were detected. The concentration range of SCCPs was 79.8 ng/g dw to 3879.3 ng/g dw, and the MCCPs was ND to 572.3 ng/g dw. Spearman correlation analysis indicated that the sources of SCCPs and MCCPs in edible fungi were similar (r = 0.57, p 0.01). The preponderant SCCPs and MCCPs congener group profiles were C

1.AbstractMesenchymal stem cell-derived exosome (MSC-EXO) transplantation has been suggested as an efficacious treatment to suppress spinal cord injury (SCI)-triggered neuroinflammation. However, an ethically acceptable method to continuously deliver MSC-EXOs to acute spinal lesions, without damaging nearby tissues/axons, has never been achieved. In this study, we fabricated a device comprising a patch containing MSCs and a microneedle array (MN-MSC patch) to treat severe SCI. When topically applied to an acute spinal lesion beneath the spinal dura, the soft microneedle (MN) array with reasonable mechanical strength avoided damaging the nearby spinal tissues, and the porous microstructure of MNs facilitated highly efficient MSC-EXO delivery. With the capacity for sustained delivery of MSC-EXOs, the MN-MSC patch was evaluated in a contusive rat SCI model. The MSCs encapsulated in the patch could survive for at least 7 days, encompassing the optimal time window for downregulating SCI-triggered neuroinflammation. As a result, MN-MSC patch treatment led to reduced cavity and scar tissue formation, greater angiogenesis, and improved survival of nearby tissues/axons. Remarkably, rats treated by this method achieved superior muscle control and exhibited robust hindlimb locomotion functional recovery. Conclusively, the MN-MSC patch device proposed here overcomes the current dilemma between treatment efficacy and ethical issues in treating acute SCI.

Despite tremendous unmet medical needs, there is no effective pharmacological treatment to promote functional recovery after spinal cord injury (SCI). Although multiple pathological events have been implicated in SCI, the development of a noninvasive pharmacological approach to simultaneously target the different mechanisms involved in SCI remains a formidable challenge. In this study, we report the development of a noninvasive nanodrug delivery system that consists of ROS-responsive amphiphilic copolymers and an encapsulated neurotransmitter-conjugated KCC2 agonist. We show that upon intravenous administration, the nanodrugs were able to enter the injured spinal cord due to blood spinal cord barrier disruption and ROS-responsive disassembly. Remarkably, once in the injured spinal cord, these nanodrugs exhibited dual functions: scavenging ROS accumulated in the lesion to protect spared connections and increasing neuronal excitability in the injured spinal cord through targeted delivery of the KCC2 agonist to inhibitory neurons. Thus, the noninvasive treatment led to significant functional recovery in the rats with contusive SCI. Together, these findings provide a much-needed translational pharmacological approach for treating severe SCI.

Mesenchymal stem cell (MSC) transplantation was suggested as a promising approach to treat spinal cord injury (SCI). However, the heterogeneity of MSC and the lack of appropriate delivery methods impede its clinical application. To tackle these challenges, we first generated human MSCs derived from a single cell with a great homogeneity of batch quality and then developed a biocompatible injectable hydrogel to embed these cells to treat severe SCI. In a clinically relevant rat severe SCI model, we showed that the injection of MSCs with injectable hydrogel into the lesion site promoted robust functional recovery, while the intrathecal delivery of MSCs only resulted in limited therapeutic effects. Mechanistically, the hydrogel protected MSCs from the damage of harmful neuroinflammatory microenvironment in the spinal cord lesion. The hydrogel with the survived MSCs ameliorates the neuroinflammatory microenvironment of spinal cord lesion, preventing cavity formation and leads to the remnant of spared axons/tissues, which results in a better prognosis in the end.

International audience; We report, for the first time, the application of fluorinated hexagonal boron nitride nanosheets (F-BNNs) as an effective inorganic matrix for matrix-assisted laser desorption and ionization mass spectrometry (MALDI-MS) analysis of perfluoroalkyl acids (PFAAs). Fluoride modification of F-BNNs increases both enrichment ability and ionization efficiency. The method was validated using environmental water, milk, human serum samples, and zebrafish imaging that has been previously exposed to PFAAs. The method provided in this work holds considerable promise in term of rapid analysis, sample requirement, and practicability.

International audience

An intelligent surgical knife (iKnife) coupled with rapid evaporative ionization mass spectrometry (REIMS) was employed for the lipidomic profiling of fresh and frozen-thawed beef muscle. The data were obtained by REIMS and then processed using multivariate statistical analysis methods including principal component analysis-linear discriminant analysis (PCA-LDA) and orthogonal partial least-squares discriminant analysis (OPLS-DA). The discrimination of fresh and frozen-thawed meat has been achieved, and the real-time identification accuracy was 92-100%. Changes in the composition and content of fatty acids and phospholipids were statistically analyzed by OPLS-DA, and the ions of m/z 279.2317, m/z 681.4830, and m/z 697.4882 were selected as differential compounds/metabolites. The developed method was also successfully applied in the discrimination of fresh and frozen-thawed meat samples. These results showed that REIMS as a high-throughput, rapid, and real-time mass spectrometry detection technology can be used for the identification of fresh and frozen-thawed meat samples.

Linear light-processing functions (e.g., routing, splitting, filtering) are key functions requiring configuration to implement on a programmable photonic integrated circuit (PPIC). In recirculating waveguide meshes (which include loop-backs), this is usually done manually. Some previous results describe explorations to perform this task automatically, but their efficiency or applicability is still limited. In this paper, we propose an efficient method that can automatically realize configurations for many light-processing functions on a square-mesh PPIC. At its heart is an automatic differentiation subroutine built upon analytical expressions of scattering matrices that enables gradient descent optimization for functional circuit synthesis. Similar to the state-of-the-art synthesis techniques, our method can realize configurations for a wide range of light-processing functions, and multiple functions on the same PPIC simultaneously. However, we do not need to separate the functions spatially into different subdomains of the mesh, and the resulting optimum can have multiple functions using the same part of the mesh. Furthermore, compared to nongradient- or numerical differentiation-based methods, our proposed approach achieves 3× time reduction in computational cost.

Triclosan (TCS) is a ubiquitous antimicrobial used in many daily consumer products. It has been reported to induce endocrine disrupting effects at low doses in mammals, disturbing sex hormone function and thyroid function. The hypothalamus plays a crucial role in the maintenance of neuroendocrine function and energy homeostasis. We speculated that the adverse effects of TCS might be related to the disturbance of metabolic processes in hypothalamus. The present study aimed at investigating the effects of TCS exposure on the protein and metabolite profiles in hypothalamus of mice. Male C57BL/6 mice were orally exposed to TCS at the dosage of 10 mg/kg/d for 13 weeks. The hypothalamus was isolated and processed for mass spectrometry (MS)-based proteomics and metabolomics analyses. The results showed that a 10.6% decrease (P = 0.066) in body weight gain was observed in the TCS exposure group compared with vehicle control group. Differential analysis defined 52 proteins and 57 metabolites that delineated TCS exposed mice from vehicle controls. Among the differential features, multiple proteins and metabolites were found to play vital roles in neuronal signaling and function. Bioinformatics analysis revealed that these differentially expressed proteins and metabolites were involved in four major biological processes, including glucose metabolism, purine metabolism, neurotransmitter release, and neural plasticity, suggesting the disturbance of homeostasis in energy metabolism, mitochondria function, neurotransmitter system, and neuronal function. Our results may provide insights into the neurotoxicity of TCS and extend our understanding of the biological effects induced by TCS exposure.

Pristine alpine regions are ideal regions for investigating the long-range atmospheric transport and cold trapping effects of short chain chlorinated paraffins (SCCPs). The concentrations and alpine condensation of SCCPs were investigated in lichen samples collected from the southeastern Tibetan Plateau. The concentrations of SCCPs ranged from 3098 to 6999 ng/g lipid weight (lw) and appeared to have an increasing trend with altitude. For congeners, C10 dominated among all the congener groups. The different environmental behavior for different congener groups was closely related to their octanol-air partition coefficient (Koa). C10 congeners showed an increasing trend with altitude, whereas C13 congeners were negatively correlated with altitude. Volumetric bioconcentration factors (BCF) of SCCPs reached 8.71 in lichens, which were higher than other semivolatile organic compounds (SVOCs) such as organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and hexabromocyclododecane (HBCD). These results suggested that SCCPs were prone to accumulate in the lichen from the air and provided evidence for the role of lichens as a suitable atmospheric indicator in the Tibetan Plateau.

Purification of antibodies has become a critical factor in antibody production. A high-purity specific antibody against antigens, especially small molecules, seems to be difficult to obtain, even with the help of a protein A affinity column, which is a conventional and broadly used ligand for the separation of antibody and non-antibody proteins. Therefore, it is urgent to develop a cheap, simple, efficient, and stable method to separate the specific antibody from other antibodies. In this study, to improve the sensitivity and accuracy of immunoassay results, enrofloxacin (ENR) was grafted onto polyethylenimine (PEI) by the abundant amino groups and then the whole ligand (ENR-PEI) was conjugated to CNBr-Sepharose 4B to prepare the affinity column for the purification of the specific antibody against ENR from polyclonal antibodies. Scanning electron microscopy and Fourier transform infrared spectroscopy verification showed that Sepharose 4B was successfully modified by ENR-PEI with excellent uniformity. The capacity of the prepared column could reach to 6.15 mg of specific antibody with high purity per milliliter resin due to the high coupling ratio (49.3:1) of ENR on PEI, and the IC50 value of the antibody after purification was 47.58 ng/mL with a lowest limit of detection (IC10) of 1.099 ng/mL-18 times lower than those of the antibody purified through the protein A column. All the results showed that this new kind of resin could be used as the potential ligand in the purification of the trace-specific antibody against antigens in complex mixtures with high efficiency and specificity.

Three dissociation methods, including collision-induced dissociation (CID), electron capture dissociation (ECD), and electronic excitation dissociation (EED), were evaluated for the dissociation of doubly charged glycans using sodium or magnesium ions as charge carriers. CID produced mainly glycosidic cleavages, although more cross-ring fragment ions could be obtained at higher intensities when magnesium ions were used as charge carriers [M + Mg]

Hyaluronidase (HAase) is implicated in inflammation, cancer development, and allergic reaction. The detection of HAase is significantly important in clinical diagnosis and medical treatment. Herein, we propose a new principle for the development of equipment-free and label-free paper-based flow sensors based on the enzymatic hydrolysis-induced viscosity change in a stimuli-responsive polymer solution, which increases the water flow distance on the pH indicator paper. The detection of HAase is demonstrated as an example. This facile and versatile method can overcome the potential drawbacks of traditional hydrogel-based sensors, including complex preparation steps, slow response time, or low sensitivity. Moreover, it can also avoid the use of specialized instruments, labeled molecules, or functionalized nanoparticles in the sensors developed using the polymer solutions. Using this strategy, the detection of HAase is achieved with a limit of detection as low as 0.2 U/mL. Also, it works well in human urine. Additionally, the detection of tannic acid, which is an inhibitor of HAase, is also fulfilled. Overall, a simple, efficient, high-throughput, and low-cost detection method is developed for the rapid and quantitative detection of HAase and its inhibitor without the use of labeled molecules, synthetic particles, and specialized instruments. As only minimal reagents of HAase, HA, and paper are used, it is very promising in the development of commercial kits for point-of-care testing.

This paper investigates the efficacy of zero-interest early payment financing (alternatively referred to as early payment) and positive-interest in-house factoring financing in a pull supply chain with a capital-constrained manufacturer selling a product through a capital-abundant retailer. Early payment is the prepayment of a wholesale cost to the manufacturer, whereas in-house factoring is a loan service provided to the manufacturer by a branch financing firm of the same retailer. We find that the retailer prefers early payment financing to bank financing when the manufacturer’s production cost is low. If the retailer instead offers positive-interest inhouse factoring financing to the manufacturer, then the financing equilibrium domain enlarges as compared to bank financing. Interestingly, early payment financing can outplay positive-interest in-house factoring financing if the production cost is considerably low; otherwise, vice versa. When the production cost is big enough, the retailer will not provide either early payment or in-house factoring. Furthermore, our main qualitative result sustains with an identical wholesale price across all three financing schemes and the financing equilibrium domain of early payment shrinks as demand variability grows.

Genetic engineering (GE) technology is widely used in plant modification. However, the results of modification may not exactly meet the expectations. Herein, we propose a new multi-omics method for GE plant evaluation based on the optimized use of the metID algorithm. Using this method, we found that flavonoid accumulation was at the expense of the great sacrifice of l-phenylalanine in GE tomatoes for the first time. Meanwhile, the ceramide series of sphingolipid is synthesized de novo from l-serine, and ceramides are the primary source of vesicles coated with flavonoids and secreted from the endoplasmic reticulum. Therefore, the accumulation of the ceramide series of sphingolipid changed the cell component of intracellular organelles. Furthermore, the improvement of the method allows us to identify more metabolites related to dysregulated pathways.

Traditional Chinese medicine (TCM) provides therapeutic and health care effects through dietary intake. Owing to the susceptibility of plants to contaminations, a risk assessment system is urgently needed to ensure the safe use of TCMs. In this study, the contamination levels and risks associated with the dietary intake of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) were investigated in six kinds of frequently-used TCM herbs. The concentrations varied from 144.4 to 1527.8 ng·g

α-Amylase (AMS) in human serum is a critical biomarker for the early diagnosis of pancreatic damage. In addition, the inhibition of α-amylase has long been thought to decrease the occurrence of diabetes. Thus, it is critical to construct a facile and convenient method for the determination of AMS and its inhibitor. In this study, we demonstrate a novel amylase sensor based on translating the viscosity change of the aqueous solution into the difference of the water diffusion length on a pH paper strip. AMS can be quantitatively detected by measuring the viscosity change of the amylopectin solution in the presence of AMS with different concentrations. The paper-based AMS sensor has a very high sensitivity with a detection limit of 0.017 U/mL and also shows excellent specificity. In addition, the inhibitory effect of acarbose on AMS is demonstrated with the IC

We have developed an algorithm for (re)configuration of Coupled Resonator Optical Waveguides filters. We analyze in detail the effect of the phase shift introduced by tunable Mach-Zehnder interferometers. An alternating pattern is proposed to drive every other tunable coupler. We verified this algorithm to realize a user-defined all-pole filter function in circuit simulation.

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.

This paper presents a multiple case study analysis on how blockchain technology (BCT) has been adopted in organisations to support supply chain finance (SCF) based on secondary data. Findings from the multiple case analysis indicate that BCT can cope with challenges in traditional SCF, including financing range, financing cost, financing efficiency, and risk management. Before the implementation of the BCT, multiple parties’ decision on jointly operating the blockchain-based SCF platform enables them to take full advantage of their inherent resources and blockchain characteristics. Also, both the BCT and enterprises need internal and external adjustments, which are interrelated. The unexpected issues may emerge from the pilot stage, but the adjustments are still involved in the previous stages, leading to a feedback loop from the pilot stage to the redefining/restructuring stage. To realise large-scale implementation of blockchain-based SCF solutions, more stakeholders need to be motivated to adopt the BCT, and new laws and regulations should be developed to promote the BCT adoption. Based on these findings and by applying innovation adoption theory, an overall implementation framework is proposed to provide a meaningful guidance for organisations to adopt BCT in SCF.

Programmable photonic chips allow flexible reconfiguration of on-chip optical connections, controlled through electronics and software. We will present the recent progress of such complex photonic circuits powered by silicon photonic MEMS actuators.

The payment mechanism plays an important role in coordinating a supply chain for better financial performance through cash flow optimization, which is key for today's business success. The supplier needs to decide on two issues regarding the payment mechanism: (a) the payment term, whether to collect payment early or late, and (b) the payment approach, to collect personally or through a third party. Focusing on these two issues, this study examines and compares the influence of three supply chain finance schemes: early payment, delayed payment, and reverse factoring on the financial performance of the supplier and retailer. We found delayed payment offers additional benefits to the supplier and retailer when the supplier has the financing advantage (i.e., a lower capital cost), and early payment and reverse factoring offer additional benefits to the supplier and retailer when the retailer has the financing advantage. With the bank's involvement and intermediation role, the increase in profits for the supplier and retailer, when using reverse factoring, is even higher than when early payment is used. The greater the difference in capital cost between the supplier and retailer, the greater the efficiency of the three financial schemes. Additionally, the financial schemes are more valuable with a higher production cost and higher demand volatility. Our study provides incentives and guidelines for the supplier and retailer to offer and use various financial programs to achieve better financial performance when faced with stochastic customer demand.

Aiming at the limitation of describing the semantic attributes of target classification, this paper proposes an adaptive weighted fusion feature based zero-sampling image classification algorithm. Firstly, the fusion weights are initialized randomly. Meantime, the semantic vector features and semantic attributes of the text are fused by neural network. Then, particle swarm optimization algorithm is used to optimize the weight of feature fusion. Finally, the features of weighted fusion are regarded as the transfer knowledge of the classification of zero-sampling images. The experimental results show that the classification algorithm based on adaptive weighted fusion for the zero-sampling image has an accuracy rate of 88.9% on the Animals with Attributes (AWA) data set, which illustrates the effectiveness. What's more, the proposed algorithm also improves the stability of the classification model for the zero-sampling image compared with the fusion feature.

We propose a novel filter circuit that incorporates a balanced Mach-Zehnder interferometer (MZI) loaded with a double coupled ring resonator. A global optimization method is applied to optimize the proposed auto-regression/moving average (ARMA) filter to a specific target function.

Two polysaccharides from Crocus sativus petals (PCSPs), PCSPA and PCSPB, presented immunopotentiatory activity through activating macrophages via MAPK and NF-κB pathway. In this study, two PCSPs were investigated for the adjuvant effects and underlying mechanisms using ovalbumin (OVA) in mice. PCSPA and PCSPB remarkably not only boosted the OVA-specific IgG antibody and its isotype titers, but strengthened splenocyte proliferation and natural killer cell activities in immunized mice. Both PCSPs also dramatically triggered the production of Th1- and Th2-cytokines and facilitated the gene expression of Th1- and Th2-cytokines and transcription factors in OVA-stimulated splenocytes. In mechanisms, two PCSPs rapidly elicited the gene and protein expression of cytokines and chemokines, 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. These findings demonstrated that PCSPs enhanced and improved immune responses and simultaneously elicited Th1- and Th2-immune responses to OVA through activating innate immune microenvironment, and that they could act as promising vaccine adjuvant candidates.

Organophosphates (OPEs) are manmade organic pollutants that are widely used as flame retardants, plasticizers, and antifoaming and hydraulic agents. In this study, seven OPEs in seawater and sediment from the Yellow Sea and East China Sea were determined to study the distribution and diffusion behavior, and to evaluate the environmental risks. The ΣOPEs in the seawater and sediments ranged from below the method detection limit (MDL) to 497.40 ng/L and fromMDL to 66.50 ng/g dw, respectively. Tri-n-butyl phosphate (TnBP), tris-(1, 3-Dichloro-2-Propyl) phosphate (TDCPP), and tri-meta-cresyl phosphate (TmCP) were the dominant OPEs in the seawater and sediments. OPEs were mainly distributed in coastal areas and the South Yellow Sea, indicating that they are mainly affected by land-based pollution and ocean currents. Fugacity analysis shows that tri-para-cresyl phosphate (TpCP) was in a state of equilibrium, while TDCPP, TnBP, and TmCP other OPEs tended to diffuse from sediment to water. The diffusion behavior of OPEs is mainly affected by their chemical properties. Hazard quotient (HQ) values of TmCP and TpCP in sediment samples were1.0, indicating high ecological risks to aquatic organisms.

With the frequent use of chemical pesticides, the current-use pesticides (CUPs) emerge and concentrate in the sea. The partition between the sediment and seawater is essential for understanding the environmental fate of CUPs. However, there is little research on this topic. In the present study, seventeen CUPs were screened in seawater and sediment samples collected from the Yellow Sea and East China Sea. Total concentration of 17 CUPs in surface seawater samples ranged from 9.5 to 267.3 ng/L, with 6 CUPs presenting 100% detection frequency. Carbendazim, tricyclazole, tebuconazole, atrazine and imidacloprid accounted for80% of all CUPs, which was due to their large application in the local agriculture and fishing activities. Higher concentration sites were located near the shore and Yangtze river estuary, indicating intense human activities and riverine input that elevated the level of CUPs in marginal sea. The pesticides in seawater were mainly found in the surface followed by the bottom layer, which indicated that atmospheric deposition and re-suspension played key roles for their vertical distribution characteristics. The high fugacity fraction ratios (ff 0.5) indicated the non-equilibrium state of pesticides that might have been transferred from sediment to seawater at most sites. These 17 detectable pesticides in seawater were at low levels, presenting ignorable or low toxic effects to aquatic organisms.

High-efficiency caption of pesticide residue is of vital significance for environmental safety monitoring. Herein, a hexagonal boron nitride nanosheets-based magnetic composite (Fe

Background 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. Objectives To assess the associations of PFAS mixture, branched isomers and emerging alternatives of PFAS with male reproductive hormones. Methods 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. Results 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. Conclusions 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.

This research presents a theoretical framework to investigate how firms with limited resource maintain and improve their performance facing the problems incurred by product complexity. It considers operational level supplier collaboration as firms’ strategy to reduce the negative impact of product complexity. It also examines the mediating role of risk management capabilities between supplier collaboration and firms’ performance. Survey data was collected from 264 U.S. manufacturing firms to test the hypothesized relationships in the proposed model using Structure Equation Modeling methodology. The findings indicate that product complexity motivates firms to collaborate with their suppliers. Supplier collaboration at operational level enables firms to achieve better performance through improving firms’ risk management capabilities toward normal risks, internal processing risks, and extraordinary risks with limited resource investment. This research contributes to risk management literature through conceptualizing the concept of risk management capabilities and empirically testing its role as a mediating factor between supplier collaboration and firms’ performance. The findings of this research also provide useful insights about how to handle product complexity through basic level collaboration with suppliers.

Calculation of isotopic distribution is a valuable but challenging task in biological mass spectrometry. An algorithm to simulate both isotope aggregated and fine structure is proposed in this paper. The algorithm generates isotopic distribution of a given molecular formula by vector manipulation and change-making strategy based on the concept of denomination system. Additional feature of the algorithm can provide isotope fine structure within an interested m/z window. The performance of the algorithm is evaluated by a number of testing molecules. It is shown that the algorithm is accurate and efficient, providing an alternative solution to the conundrum of isotopic distribution calculation. The program has been implemented as an interactive Matlab package, an independent GUI software, and an open-source Python package, which can be conveniently downloaded and installed.

Firms aim to achieve time-based competitiveness to reach their target market sooner and better to meet consumers’ changing demands and cater to rapidly changing markets. One efficient approach is t...

A 2D Z-scheme BiVO4/g-C3N4 photocatalyst was successfully synthesized by a two-step hydrothermal/calcination method for overall water splitting. Morphology design to restrain the growth of BiVO4 nanoplates with thickness around 20 nm was achieved by adjusting the pH value and introducing graphene sheets. Then, the BiVO4/g-C3N4 (BVO-CN) hybrid photocatalysts were fabricated with different mass ratios of two components. The structures and optical properties of the BVO-CN photocatalysts were characterized by transmission electron microscope, scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, and photoluminescence spectroscopy. In application, the BVO-CN photocatalysts exhibited the catalytic overall water splitting activity up to 15.6 μmol h−1 for H2 production and 7.3 μmol h−1 for O2 evolution under visible light irradiation. A possible Z-scheme mechanism is proposed for the enhanced photocatalytic activity and was further confirmed by electron spin resonance spectroscopy. This study demonstrated enhanced overall water splitting photocatalytic performance of BiVO4/g-C3N4 photocatalyst by constructing a 2D nanoplates morphology and shed light on the morphology design of Z-scheme semiconductor materials.

With an increasingly open global economy and advanced technologies, some third-party logistics providers (3PLs), such as Eternal Asia, have emerged as supply chain orchestrators, linking buyers with manufacturers worldwide. In addition to their traditional transportation services, these orchestrators provide procurement and financial assistance to buyers in the supply network, especially small- and medium-sized enterprises (SMEs) in developing countries. Oftentimes, the 3PLs can obtain payment delay arrangements from the financially stronger manufacturers, which in turn can be partially extended to the SME buyers, alleviating their high costs of capital. To illustrate the efficiency improvements of the aforementioned practice, we use a model to explicitly capture the cash-flow dynamics in a supply chain consisting of a manufacturer, a buyer, and a 3PL firm and explore the conditions under which this innovation benefits all parties in the supply chain so that the business model is sustainable. We characterize these conditions and show that the supply chain profit can be higher under leadership by the 3PL than by the manufacturer. The intermediary role of the 3PL is crucial, in that its benefit may vanish if the manufacturer chooses to directly grant payment delay to the buyers. We demonstrate that the benefit is more likely to occur with more buyers. We further identify the unique Nash bargaining solution for the transportation time and the payment delay grace period. The online appendix is available at https://doi.org/10.1287/msom.2017.0667 . This paper has been accepted for the Manufacturing & Service Operations Management Special Issue on Value Chain Innovations in Developing Economies.

Short-chain chlorinated paraffins (SCCPs) were added to the Stockholm Convention on Persistent Organic Pollutants (POPs) at the eighth meeting of the conference of the parties in 2017. As a consequence, increasing environmental attention and international regulation on SCCPs is expected in the future. Inhalation uptake of particulate matter (PM) was an important exposure pathway for POPs into the human body. In the present study, a total of eighty PM2.5 samples were collected in the four seasons of the year at an urban site (Shandong University, Jinan) in Shandong province to investigate the seasonal changes of SCCPs and their inhalation exposure risks to human health. The concentrations of SCCPs ranged from 9.80 to 105 ng m−3, with the mean value of 38.7 ng m−3. The highest concentrations of SCCPs were detected in winter, while the lowest concentrations were in summer. SCCPs concentrations were positively correlated with the mass concentrations of PM2.5 (r = 0.629, p

The PM2.5 samples at an urban site (JN) and a suburban site (QXT) were simultaneously collected in a heavily polluted city in North China Plain (Jinan) from March to December in 2016, and eighteen polycyclic aromatic hydrocarbons (PAHs) were analyzed. The annual average ∑PAHs concentrations were 39.8 ± 36.6 and 23.6 ± 14.0 ng m–3 at JN and QXT, respectively, with the highest concentrations observed during winter. PHE and CHY were the two most abundant PAHs, accounting for 31.1% at JN and 34.2% at QXT. Source apportionment analyses from the results of Principal Component Analysis (PCA) revealed that coal/biomass combustion and vehicle emission were the major PAH sources in PM2.5. The ratio of LMW + MMW (LMW: low molecular weight; MMW: middle molecular weight) PAHs to ∑PAHs at JN was significantly lower (p < 0.001) than that at QXT, indicating coal/biomass burning made more significant contribution to suburban area than that to urban area. Conversely, vehicle emission worked more effectively to urban area. The total benzo[a]pyrene (BaP) equivalent concentration (BaPeq) of PAHs (gas + particle phases) was 9.66 times higher than the standard value (1.00 ng m–3) and mainly originated from PAHs in particles (93.1%) with the highest contributor of Benzo(a)pyrene (BaP, 60.8%) at the urban site of Jinan in winter. The total incremental lifetime cancer risk (ILCR) assessment suggested that all age groups may have potential health risk at JN in winter except for infant. The Concentration Weighted Trajectory (CWT) model indicated that local emission and short-distance transport were the main sources of PAHs during spring and winter, and long-range transport played a key role on PAH concentrations in summer and autumn.

Multiple studies have examined the relationship between PFAS and semen quality, but none has explored the associations of PFAS mixture that includes emerging alternatives and branched isomers.22 PFAS, including 10 linear legacy PFAS, 7 branched isomers, 3 short chain alternatives and 2 components of F53B [e.g., 6:2 chlorinated polyfluorinated ether sulfonate (Cl-PFESA)] were quantified in blood plasma among 740 healthy men. Five semen quality parameters (i.e., volume, count, concentration, total motility and progressive rate) were assessed. Multiple linear regression and three multiple pollutant models (i.e., adaptive elastic net regression, quantile based g-computation, and XGBoost method) were used to assess the associations of individual PFAS and PFAS mixture with semen quality and the potential interactive effects among congeners.After adjusting for selected confounders, perfluorobutane sulfonate (PFBS) and perfluorohexane sulfonate (PFHxS) presented significant and negative associations with sperm count [βIn the current cross-sectional study, we found that two emerging PFAS replacements (i.e., 6:2 Cl-PFESA and PFBS) and PFHxS exposure were associated with reduced semen concentration, total sperm count and motility in men. Meanwhile, significant positive associations between PFHpS and sperm count and concentration were also observed. But there were no consistent associations between PFAS mixture, branched isomers and semen quality.