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Graphene (Gr) is a monolayer of carbon atoms in a two-dimensional honeycomb lattice, and has derivatives of graphene oxide and reduced graphene oxide. Gr is widely used in various fields for its good optics, conductivity, mechanical properties, low toxicity, antibacterial properties, biocompatibility and stability. Graphene oxide and reduced graphene oxide have similar properties to Gr, and all three materials have advantages and disadvantages and are often not used alone but are composited with other materials to improve their properties for a particular application. From the perspectives of the toxicity and antibacterial properties of Gr and its derivatives, this paper reviews their uses in treating skin wounds and tumours, promoting the regeneration of skeletal muscle and bone, and facilitating drug loading and diagnosis. The problems associated with these applications are analyzed and solutions are suggested. Future research and development prospects for Gr-based materials are presented.

Background Wilson disease is a rare, disabling, neurological genetic disease. Biomarkers of brain damage are less well developed. Objective The aim of this study was to evaluate the utility of plasma glial fibrillary acidic protein as a biomarker for neurological involvement in patients with Wilson disease. Methods This prospective cross-observational study compared plasma glial fibrillary acidic protein concentration among different subtypes of patients with Wilson disease and healthy control subjects. Plasma glial fibrillary acidic protein levels were measured in 94 patients and 25 healthy control subjects. Patients were divided into two subtypes: patients with neurological manifestations (n = 74) or hepatic manifestations (n = 20). Results Median levels of plasma glial fibrillary acidic protein were significantly elevated in patients with neurological manifestations (143.87 pg/mL) compared with those with hepatic manifestations (107.50 pg/mL) and healthy control subjects (86.85 pg/mL). Receiver operating characteristic curve revealed that a plasma glial fibrillary acidic protein cutoff value of 128.8 pg/mL provides sufficient sensitivity (80.0%) and specificity (63.5%) to differentiate patients with neurological manifestations from those with hepatic manifestations. Conclusions Plasma glial fibrillary acidic protein may serve as a biomarker for distinguishing different subtypes of Wilson disease. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

In this work, an irregular calixpyridinium-suramin sodium supramolecular assembly was constructed by the strong host-guest electrostatic interactions. More interestingly, a novel regular spherical supramolecular assembly was also fabricated by the hydrogen bonding interactions between suramin sodium and the UV accelerated addition product of deprotonated calixpyridinium in water. The same principle was also applied to construct a UV accelerated regular spherical self-assembly by the addition product of deprotonated calixpyridinium in water. Compared with the complicated and irreversible covalent connection of the light-responsive groups to the building block, which is one of the common means of obtaining light-responsive supramolecular systems, this finding not only provides a smart, facile, and universally applicable method to construct deprotonated calixpyridinium-based light-responsive host-guest systems but also provides a new idea for the development of other novel light-responsive building blocks.

Aims This study aimed to compare the differences in the bacterial community structure of Lycium barbarum rhizosphere and elucidate the contribution of rhizosphere bacteria to the active ingredients of L. barbarum fruit. Methods and Results This study investigated the soil and meteorological characteristics of L. barbarum rhizosphere during three growth stages across three production regions of China. High-throughput sequencing showed significant differences in the bacterial community diversity of L. barbarum rhizosphere across the three production regions, and norank_o_Gaiellales, norank_f_Anaerolineaceae and norank_f_AKYG1722 were the highest in Ningxia. In addition, regression and path analysis revealed that pH, norank_o_Gaiellales and norank_f_AKYG1722 significantly promoted the accumulation of total sugar and flavonoids in L. barbarum fruit directly or indirectly. Soil organic matter (SOM), norank_f_Anaerolineaceae and humidity significantly promoted the accumulation of betaine. The average temperature during the growth stages, norank_f_AKYG1722, and norank_o_Gaiellales promoted the accumulation of polysaccharides. Conclusions The interaction between rhizosphere bacteria and environmental factors promoted the accumulation of active ingredients in L. barbarum fruits. Significance and Impact of the Study Our results provided insights to improve the quality of L. barbarum fruit.

The ITER magnet system consists of TF coil, PF coil, CS and CCs. The bottom correction coils are one set of ITER Correction Coils (CC), which is used to reduce the range of magnetic error fields created by the other coils. Before the BCCs are finally positioned, it needs to be temporarily supported in Pit. The design and analysis of BCC temporary supports need to be considered load combinations when BCCs are placing in the Pit. The FE analysis results meet the design requirements and stress evaluation criteria. An engineering calculation, like bolt joint, assuring the integrity of the analysis work. This work could provide a necessary reference for the manufacture of BCC Temporary Supports.

ITER Bottom Correction Coils (BCCs) as an important part of the ITER magnet system, is used to compensate for the error field of other coils due to non-axial symmetry. The BCC lifting frame will be used in the process of lifting the BCC to the temporary position in the pit, the BCC lifting frame also applies to Top Correction Coils (TCCs). Considering the load combination of BCC lifting frame according to the actual working conditions, the results of finite element analysis prove that the designed BCC lifting frame meet the stress and deformation evaluation standard.

In order to develop superconducting joint technology, a field decay system was setup for the joint resistance measurement. To verify the feasibility of the testing system, a YBCO conductor joint, which was a single-turn loop coil with joint soldered by low-temperature solder, has been fabricated and used as the sample. The testing results have been compared with that by the standard four-probe method. The resistance measured by the four-probe method is 5.75x10−8Ω, and using this system, the performance of the joint is 4x10−8 Ω. The measured resistance by field decay method is less than that by the four-probe method. This is mainly due to the self-inductance of the YBCO closed coil based on FEM is smaller than the actual value.

Silybum marianum is a traditional Chinese medicine that has been used for treating liver disease. Silybin consisting of silybin A and silybin B, is a member of Silybum marianum, and exerts a therapeutic effect on many diseases. However, the protective effect of silybin on cisplatin-induced neurotoxicity and the stereoisomer contributing to the effect remain unknown.The present study aimed to study the effect of silybin on cisplatin-induced neuronal injury, compare the difference of protective effect between silybin A and silybin B, and the potential mechanism.High performance liquid chromatography (HPLC) was used to separate silybin A and silybin B. X-ray crystallographic analysis in combination with experimental and calculated ECD were performed to identify the structure of silybin A and silybin B. The toxicity of the silybin or cisplatin against murine hippocampal neuronal HT22 cells was determined through MTT assay. The cell cycle and cell apoptosis were measured by PI staining and Annexin V-FITC/PI staining, respectively, and then subjected to flow cytometry. Western blot analysis was conducted to quantify the expression of proteins related to apoptosis and DNA damage. Immunofluorescence was used to evaluate the expression of DNA damage marker. In vivo experiment, the behavioral analysis was determined through pole test, swimming test and Morris water maze test. The index of superoxide dismutase (SOD), reduced glutathione (GSH), total antioxidant capacity (T-AOC) and lipid peroxidation (LPO) were examined to evaluate the antioxidant capacity in mice brain. Nissl staining and Tunel assay were used to detect the neuronal viability and apoptosis in hippocampus.We successfully separated and identified silybin A and silybin B. We found both silybin A and silybin B alleviated cisplatin-induced apoptosis and cell cycle arrest in HT22 cells, and silybin B was more effective. We chose silybin B for further mechanism investigation, and found silybin B alleviated DNA damage by enhancing phosphorylation of ATR and decreasing expression of γ-H2AX. In the in vivo experiment, we observed that silybin B markedly improved the behavioral abnormalities in cisplatin-treated mice, reduced LPO level while increased SOD, GSH and T-AOC in mice brain tissue. Nissl staining and Tunel assay showed that silybin B alleviated cisplatin-induced hippocampal damage.These results suggest that silybin B might serve as a promising drug candidate in mitigating cisplatin-induced neural injury in the brain and thereby improving the chemotherapeutic outcomes.

Three new quaternary Zintl phases with the "9-4-9" formula, Ae9Mn4-xAlxSb9 (Ae = Ca, Yb, Eu), have been synthesized using Pb as the metal flux, and their crystal structures have been established by single-crystal X-ray diffraction. Both Ca9Mn2.91(4)Al1.09Sb9 and Yb9Mn3.59(6)Al0.41Sb9 are isostructural with Ca9Mn4Bi9, and they crystallize in the orthorhombic space group Pbam with unit cell dimensions of a = 12.4571(8), 12.2884(16) A, b = 22.1352(16), 22.024(3) A, and c = 4.6012(3), 4.6187(6) A, respectively. Their anionic structures can be viewed as infinite ribbons based on corner-shared tetrahedrons. Also, Eu9Mn2.87(4)Al1.13Sb9 has the space group Cmca and a = 9.4883(7) A, b = 23.6895(18) A, and c = 24.4845(19) A. The structural relationships between Ca9Mn2.91(4)Al1.09Sb9 and Eu9Mn2.87(4)Al1.13Sb9 are compared and discussed as well. The successful Al3+ substitution provides additional electrons to the compounds to achieve structural stability. Magnetic susceptibility and electrical resistivity measurements, performed on single crystals of Eu9Mn2.87(4)Al1.13Sb9, indicate complex magnetic properties and semiconductor behavior. The physical properties of Yb9Mn3.59(6)Al0.41Sb9 are similar to those observed for Yb9Mn4.18(2)Sb9.

Recently, the application of sulfur (S) has been recommended to control the accumulation of cadmium (Cd) in rice in contaminated paddy soil. However, the effects of exogenous S on Cd transfer in paddy rice systems under different water-management practices have not been systematically investigated. Pot experiments were performed to monitor the composition of soil pore water and the Cd accumulation in iron plaque and rice tissue were compared under different S (0 and 200 mg/kg Na

Two new steroidal glycosides oxystauntoside A (1) and oxystauntoside B (2), together with sixteen known compounds (3–18) were isolated from the 95% ethanol extract of Merrillanthus hainanensis. Their structures were characterized by extensive spectroscopic analysis including NMR and mass spectra and single crystal X-ray crystallography. The absolute configuration of 1 and 2 were further determined by ECD calculations. All of these compounds were isolated from M. hainanensis for the first time. All the fractions and compounds were tested for the anti-inflammatory activity against the TNF-α factor. The ethyl acetate fraction showed the most potent inhibition (71.3%) at 10 μg/mL and compounds 5 (78.9%) and 9 (73.4%) in this fraction with both carboxyl and phenolic hydroxyl groups showed significant inhibition at 10 μM. Our study provided the first scientific report for the medicinal value of M. hainanensis.

Broad area semiconductor laser (BAL) has poor lateral beam quality due to lateral mode competition, which limits its application as a high-power optical source. In this work, the distributed Bragg reflector laser diode with tapered grating (TDBR-LD) is studied. By changing the lateral width, the tapered grating increases the loss of high-order lateral modes, thus improving the lateral characteristics of the laser diode. The measuring results show that the TDBR-LD can achieve a single-lobe output under 0.9 A. In contrast to the straight distributed Bragg reflector laser diode (SDBR-LD), the lateral far field divergence of TDBR-LD is measured to be 5.23° at 1 A, representing a 17% decline. The linewidth of TDBR-LD is 0.4 nm at 0.2 A, which is reduced by nearly 43% in comparison with that of SDBR-LD. Meanwhile, both of the devices have a maximum output power value of approximate 470 mW.

Background: The fungal communities inhabiting natural Ophiocordyceps sinensis play critical ecological roles in alpine meadow ecosystem, contribute to infect host insect, influence the occurrence of O. sinensis, and are repertoire of potential novel metabolites discovery. However, a comprehensive understanding of fungal communities of O. sinensis remain elusive. Therefore, the present study aimed to unravel fungal communities of natural O. sinensis using combination of high-throughput sequencing and culture-dependent approaches. Results: A total of 280,519 high-quality sequences, belonging to 5 fungal phyla, 15 classes, 41 orders, 79 families, 112 genera, and 352 putative operational taxonomic units (OTUs) were obtained from natural O. sinensis using high-throughput sequencing. Among of which, 43 genera were identified in external mycelial cortices, Ophiocordyceps, Sebacinia, Archaeorhizomyces were predominant genera with the abundance of 95.86%, 1.14%, 0.85%, respectively. A total of 66 genera were identified from soil microhabitat, Inocybe, Archaeorhizomyces, unclassified Thelephoraceae, Tomentella, Thelephora, Sebacina, unclassified Ascomycota, unclassified Fungi were predominant genera with an average abundance of 53.32%, 8.69%, 8.12%, 8.12%, 7.21%, 4.6%, 3.08% and 3.05%, respectively. The fungal communities in external mycelial cortices were significantly distinct from the soil microhabitat. Meanwhile, seven types of culture media were used to isolate culturable fungi at 16°C, resulted in 77 fungal strains isolated by rDNA ITS sequence analysis, belonging to 33 genera, including Ophiocordyceps, Trichoderma, Cytospora, Truncatella, Dactylonectria, Isaria, Cephalosporium, Fusarium, Cosmospora and Paecilomyces, etc.. Among all culturable fungi, Mortierella and Trichoderma were predominant genera. Conclusions: The significantly differences and overlap in fungal community structure between two approaches highlight that the integration of high-throughput sequencing and culture-dependent approaches would generate more information. Our result reveal a comprehensive understanding of fungal community structure of natural O. sinensis, provide new insight into O. sinensis associated fungi, and support that microbiota of natural O. sinensis is an untapped source for novel bioactive metabolites discovery.

Hookerianones A – E (1–5), five new polyprenylated acylphloroglucinols (PPAPs), along with six known ones, were isolated from the aerial parts of Hypericum hookerianum. Their structures were elucidated by analyses of MS, NMR, chiroptical properties, biogenetic pathway, and/or single crystal X-ray diffraction. A ubiquitin-rhodamine 110 assay showed that furohyperforin and hypercalin C, two representative PPAPs in this plant, inhibited more than 90% USP7 at the concentration of 10 μM.

Perilla frutescens (L.) Britt. (Lamiaceae) is a traditionally medicinal herb in East Asian countries to treat various diseases. In present study, the low-polarity constituents of the aerial parts of P. frutescens were investigated and their anti-inflammatory effect on lipopolysaccharide (LPS)-stimulated RAW264.7 cells were assayed. Three new furanoid monoterpenoids, named as frutescenones A - C (1-3), together with thirteen known compounds (4-16) were isolated and identified on the basis of extensive spectroscopic analysis and a single-crystal X-ray diffraction study. Among these components, 1 is an unusual monoterpenoid with 2,3'-bifuran skeleton, and 3 is a rare perillaketone-adenine hybrid heterodimer, while the revised NMR arrangements of 4 were reported at the first time. Furthermore, monoterpenoid 4 and alkaloid 15 showed remarkably inhibitory effect on the production of inflammatory mediator (NO) and pro-inflammatory cytokines (TNF-α and/or IL-6) in LPS-stimulated RAW264.7 cells.

In a paper published in the International Journal of Production Economics (IJPE) [Zhang, R., Kaku, I., Xiao, Y., 2012. Model and heuristic algorithm of the joint replenishment problem with complete backordering and correlated demand. International Journal of Production Economics 139 (1), 33–41], the authors proposed a joint replenishment problem (JRP) model with complete backordering and correlated demand caused by cross-selling. The model was transformed into minimizing a function with respect to multiples of a major item's order cycle, and a heuristic algorithm was developed for near-optimal solutions. In this paper, we reinvestigate the problem and analyze the mathematical property of the model to develop an exact algorithm. The algorithm can obtain global optima and exhibits polynomial complexity.

Three new quaternary Zintl phases with the "9-4-9" formula, Ae

Background: Hereditary spastic paraplegia type 5 (SPG5) is an ultra-rare neurogenetic axon-degenerative disease. The absence of treatment to prevent disease progression represents a major unmet clinical need. With a greater understanding of the pathophysiological basis of SPG5, opportunities have emerged for providing a targeted mechanistic therapy. The aims of this preliminary study were to investigate the efficacy of a PCSK9 inhibitor, Evolocumab, as a cholesterol-lowering therapy for reducing the accumulation of neurotoxic oxysterols and to evaluate the effects on axonal degeneration. Methods: This was as an open-label, evaluator-blind, single-center pilot study in which 23 SPG5 patients each received a single subcutaneous injections of 420 mg Evolocumab. Clinical data, CSF and blood were collected for analysis at enrollment and subsequent day 30. Induced pluripotent stem cells (iPSCs) were generated from the fibroblasts of a SPG5 patient to assess the mechanism of PCSK9 inhibitor’s effect on treatment. Findings: This trial is the largest sample-size prospective study among any treatment trial for SPG5. In this relatively homogeneous group of SPG5 patients (96% carried the same known nonsense mutation c.334 C>T; the median age was 34 years; disease duration was 16 years), we found that PCSK9 inhibitor significantly lowered levels of the toxic metabolite 27-hydroxycholesterol (27-OHC) in plasma (median (IQR), 589(487-644) vs. 396(348-468) ng/ml , P < 0.001). CSF 27-OHC decreased in 12 (71%) patients with a median reduction by 11% from the median 10 ng/ml before treatment to 8.3 ng/ml after treatment (P = 0.012). Most importantly, axonal degeneration, assessed by using neurofilament light (NFL) as a quantitative biomarker, receded at 30 days after single-dose Evolocumab treatment. Additionally, using iPSC-derived motor neurons, this study also showed that PCSK9 inhibitor had anti-apoptosis activity in SPG5 patients. Interpretation: The potential biological activity of cholesterol modulation for SPG5 patients, that is, alleviation of damage to axons from the effects of neurotoxic oxysterol, as well as the absence of adverse effects associated with the use of PCSK9 inhibitor therapy documented here deserves, in fact urges, full evaluation by well-designed long-term clinical trials. Trial Registration: This study is registered with ClinicalTrials.gov, number: NCT01892345. Funding Statement: This work has been supported by grants U1905210 (W.-J.C.), 81771230(W.-J.C.) and 81801130 (X.L.) from the National Natural Science Foundation of China, Joint Funds for the Innovation of Science and Technology of Fujian Province (2017Y9094) (W.-J.C.) and (2018Y9082) (N.W.), the Natural Science Foundation of Fujian Province (2019J02010) (W.-J.C.) and (2019J05076) (X.L.), the Key Clinical Specialty Discipline Construction Program of Fujian (N.W.). Declaration of Interests: All authors report no conflict of interest. Fujian medical university school of public health have received consultant fees as statistician to perform the data analysis. Ethics Approval Statement: The study protocol and informed consent procedures were approved by the institutional review board. Written informed consent was provided by the patients and their health care proxies.

A microporous metal-organic framework containing Co(II) as nodes with a polar pore surface, {[Co(SDB)(bpdh)0.5]}n (1), was formed via reaction of a –SO2 functionalized organic connector (H2SDB = 4,4′-sulfonyldibenzoic acid) combined with (bpdh = 2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene), N-rich spacer under the solvothermal conditions. The diamond channels of the framework for 1 have a size of 6.1 Å along the b axis of the crystal, and the surface area of BET is 541 m2·g−1. FT-IR spectra demonstrated 5-Fu loading and ultraviolet–visible spectra showed the loading capacity of 5-Fu of 27.36%. Compared with normal tissue of pH = 7.4, the drug release in simulated cancer tissue of pH = 5.7 was gradual, showing a rational pH-responsive drug release. Clone formation experiments and CCK-8 assay confirmed the antitumor activity of 5-Fu@1a against EOMA hemangioma cells. Detection of apoptotic protein level and Annexin V-FITC/PI analysis showed that 5-Fu@1a could induce the apoptosis in caspase-dependent manner. Antitumor ability of the 5-Fu was verified by experimental data in vivo, which is consistent with the experimental data in vitro.

To explore the association between soil selenium levels and the risk of diabetes in Chinese adults aged 35-74 years.Data for this study were derived from the China Chronic Diseases and Behavioral Risk Factors Surveillance 2010 survey. Selenium concentrations in soil were obtained from the Atlas of Soil Environmental Background Values in China. A two-level binary logistic regression model was used to determine the association between soil selenium concentrations and the risk of diabetes, with participants nested within districts/counties.A total of 69,332 participants aged 35-74 years, from 158 districts/counties were included in the analysis. Concentrations of selenium in soil varied greatly across the 158 districts/counties, with a median concentration of 0.219 mg/kg (Excessive selenium concentrations in soil could increase the risk of diabetes among Chinese adults aged 35-74 years.

In this work, the host–guest interaction between calixpyridinium and anionic anticancer drug Alimta was studied in aqueous media. Spherical supramolecular amphiphilic assembly rather than simple complex was accidentally fabricated by the complexation of calixpyridinium with Alimta. It is the third kind of anionic guest to be discovered to form the higher-order assembly by the complexation of calixpyridinium besides polyanionic guest and anionic gemini surfactant guest. The finding of this assembly approach supplies a new idea to construct various self-assembly architectures in water via the complexation of calixpyridinium with anionic drugs. The resulting calixpyridinium–drug assemblies may also have the potential to adjust the effects of drugs.

Three 3D structures coordination polymers: [Ln(C2O4)(CH3COO)(H2O)]n (Ln = Gd, Eu, Tb) featuring a three-dimensional (3D) structure were synthesized with light-weight ligands. 1Gd owing to the higher magnetic density based on the large mass ratio (metal/ligands) and 3D structures, shows good MCE with −ΔSmmax = 39.5 J kg−1 K−1 at 2 K and ΔH = 7 T. Meanwhile, the luminescence properties and luminescence decay of 2Tb and 3Eu were investigated, the results showed that 2Tb and 3Eu present characteristic emissions of EuIII and TbIII ions.

In this work, a water-soluble fluorescent and colouring macrocycle deprotonated-calixpyridinium was obtained by a simple pH modulatory strategy. This type of fluorescent and colouring macrocyclic skeleton as host will be certainly applied in a large number of fields, especially in the sensing area. Herein, a near white-light emission was carried out by an innovative method of deprotonated-calixpyridinium-based host–guest interactions employing camptothecin sodium as the guest. Moreover, the pH-responsive luminescence color change of calixpyridinium–camptothecin sodium complex was further applied for the high selective detection of arginine in pure water and real samples, which is quite important in the accurate diagnosis of various disorders. The newfound pH-dependent luminescent and colouring properties of calixpyridinium will also provide an alternative idea for the development of other novel fluorescent and colorimetric macrocyclic sensors.

A matured oocyte has experienced three critical division stages: (1) proliferation in early fetal stage, (2) meiotic arrest at diplotene of prophase I, and (3) meiotic resumption and extrusion of the first polar body. The abnormalities of these stages are associated closely with female reproduction problems including primary ovarian insufficiency (POI), the pathogenic mechanisms of which consist of insufficient initial follicle number, accelerated follicle loss, and arrest of follicle development. Recently, many meiotic associated genetic factors were identified to be mutated in POI patients and mouse models, revealing the association between meiosis and ovarian reserve. In this review, we provide an overview of the genetic factors involved in meiotic prophase I and their pathogenic mechanisms in POI.

Recurrence of atrial fibrillation (AF) after ablation is still high. Perindopril plays an essential role in AF induction and maintenance.We aimed to prove that perindopril (8 mg) could prevent recurrence after pulmonary vein isolation.Patients with paroxysmal AF who received radiofrequency ablation were randomized to a 3-month course of perindopril 8 mg once daily (perindopril group) or placebo (placebo group). Angiotensin-II (Ang-II) therapy and standard transthoracic echocardiography were performed. All 256 patients with paroxysmal AF who received radiofrequency ablation were randomized. And we followed them for complete 1 year. The 3-month recurrence and the 1-year recurrence were compared between the 2 groups.The 3-month recurrence of AF was observed in 33 (26.19%) of 126 patients in the placebo group vs 19 (14.62%) of 130 patients who received perindopril 8 mg once daily (χ2, P = .021). One-year recurrence of AF was observed in 36 (28.5%) of 126 patients in the placebo group as compared with 21 (16.2%) of 130 patients who received perindopril after 1 year (P = .017). The κ value was 0.94 in the control group (P.001) and 0.96 in the perindopril group (P.001) between 3-month and 1-year recurrence. The Ang-II level was related to the left atrial distance with the reduction in AF recurrence (r = 0.17, P = .005 at 3 months; r = 0.25, P.001 at 1 year).Perindopril is an effective and safe treatment for the prevention of AF recurrence after radiofrequency catheter ablation. This effect seems to be strongly associated with a significant decrease in Ang-II level and left atrial distance.

Demand estimation is often confronted with incomplete information of censored demand because of lost sales. Many estimators have been proposed to deal with lost sales when estimating the parameters of demand distribution. This study introduces the cross-selling effect into estimations, where two items are cross-sold because of the positive externality in a newsvendor-type inventory system. We propose an approach to estimate the parameters of a jointly normally distributed demand for two cross-selling items based on an iterative framework considering lost sales. Computational results based on more than two million numerical examples show that our estimator achieves high precision. Compared with the point estimations without lost sales, all the relative errors of the estimations of demand expectation, standard deviation, and correlation coefficient are no larger than 2% on average if the sample size is no smaller than 800. In particular, for demand expectation, the error is smaller than 1% if the comprehensive censoring level is no larger than four standard deviations (implying a 2σ-level of safety stock for each item), even if the sample size decreases to 50. This implies that the demand estimator should be competent in modern inventory systems that are rich in data.

Land reclamation transforms a tidal flat from a marine ecosystem to terrestrial ecosystem, which significantly changes the soil ecosystem process, affecting the soil enzyme activities. Soil enzyme is involved in almost all soil biochemical processes. Clarifying the relationship between soil physicochemical properties and soil enzyme activities can reveal the changes of soil quality after reclamation and provide a theoretical basis for the scientific regulation of the soil ecosystem. In this study, a total of 72 soil samples were collected from a coastal reclamation area with different years of reclamation (0, 7, 32, 40, and 63 a) in Rudong County. The changes in soil physicochemical properties and enzyme activities within different reclamation years were analyzed by classical statistical analysis, and the relationship between soil enzyme activities and physicochemical properties was analyzed using a redundancy analysis. The results showed that longterm land reclamation had significant effects on soil physicochemical properties and enzyme activities. pH and electrical conductivity showed a decreasing trend after reclamation, while the content of soil organic carbon, total nitrogen, and total phosphorus showed a trend of "rapidly accumulate-gradually consume-accumulate again" with increasing years of reclamation. Compared with the bare flat area (0 a), amylase, dehydrogenase, and acid phosphatase activity initially increased and then decreased with increasing years of reclamation, while urease and alkaline phosphatase activities were characterized by an increase-decrease-increase trend. Meanwhile, the enzyme activities within different reclamation ages were basically higher in surface soil than deep layers. Redundancy analysis revealed that the soil physicochemical properties explained 69.8% of the variation in soil enzyme activities, and an obvious relationship existed between pH, electronic conductivity, soil organic carbon, total nitrogen, total phosphorus, and soil enzyme activities (