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1.
J Pharm Biomed Anal ; 177: 112873, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31539711

RESUMO

A rapid, sensitive and convenient analytical method of ultra-performance liquid chromatography coupled with triple-quadrupole linear ion-trap tandem mass spectrometry (UPLC-QTRAP®/MS2) was proposed for the simultaneous determination of characteristic alkaline and acidic components covering many structure types including alkaloids, phenolic acids, phenylpropanoids and flavonoids in Leonurus japonicus Houtt. (LJ). The proposed method was first reported and validated by assessing the matrix effects, linearity, limit of detections, limit of quantifications, precision, repeatability, stability and recovery of target components. The developed UPLC-QTRAP®/MS2 was successfully applied to simultaneously determine all target compounds in 38 batches of LJ from 11 different producing regions in China and five organs (including root, caulis, branch, flower and leaf) of LJ from the same stand planting base in Jiangsu Province (China). The result showed that LJ in different regions with different geographical position would affect the accumulation of different compounds, and the significant discrepancies of some target compounds were also observed in different organs of LJ due to different biosynthetic pathway and enzymes in different organs. Furthermore, both hierarchical clustering analysis and principal components analysis were performed to classify the 38 batches of LJ samples from different producing regions on the basis of target compounds. As a result, the samples could be mainly clustered into different groups, which were similar with areas classification. Overall, the presented method would be helpful for the comprehensive utilization and development of LJ resources.

2.
Nat Prod Bioprospect ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31696441

RESUMO

Terminalia Linn, a genus of mostly medium or large trees in the family Combretaceae with about 250 species in the world, is distributed mainly in southern Asia, Himalayas, Madagascar, Australia, and the tropical and subtropical regions of Africa. Many species are used widely in many traditional medicinal systems, e.g., traditional Chinese medicine, Tibetan medicine, and Indian Ayurvedic medicine practices. So far, about 39 species have been phytochemically studied, which led to the identification of 368 compounds, including terpenoids, tannins, flavonoids, phenylpropanoids, simple phenolics and so on. Some of the isolates showed various bioactivities, in vitro or in vivo, such as antitumor, anti HIV-1, antifungal, antimicrobial, antimalarial, antioxidant, diarrhea and analgesic. This review covers research articles from 1934 to 2018, retrieved from SciFinder, Wikipedia, Google Scholar, Chinese Knowledge Network and Baidu Scholar by using "Terminalia" as the search term ("all fields") with no specific time frame setting for the search. Thirty-nine important medicinal and edible Terminalia species were selected and summarized on their geographical distribution, traditional uses, phytochemistry and related pharmacological activities.

3.
Mult Scler Relat Disord ; 37: 101488, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31706167

RESUMO

BACKGROUND: Neuromyelitis optica spectrum disorder (NMOSD) is a rare demyelinating disease in need of more studies to determine effective treatment regimens. The rarity of the disorder, however, makes large randomized-controlled trials challenging. Validation of the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) code for NMO could facilitate the use of large healthcare claims data for future research. We aimed 1) to determine the positive predictive value (PPV) of the ICD-9-CM code for NMO as well as evaluate case-finding algorithms for the identification of patients with NMO/NMOSD and 2) to compare the evaluation of and treatment for pediatric versus adult patients. METHODS: This was a multicenter retrospective cohort study of patients with ≥ 1 ICD-9 code for NMO seen at 3 pediatric and 2 adult United States medical centers from 2001-2016. Using a standardized data entry form, pediatric and adult neurologists and rheumatologists reviewed patients' medical records to determine whether patients fulfilled the 2006 criteria for NMO and/or the 2015 criteria for NMOSD in order to determine the positive predictive value (PPV) for the ICD-9-CM code. Demographic and clinical information was abstracted from patient medical records to ascertain variables then evaluated in case-based finding algorithms for further identification of patients with true NMO/NMOSD. We also evaluated differences in clinical characteristics between pediatric and adult patients using chi-squared or Fisher's exact tests, as appropriate, to assess for treatment variation. RESULTS: A single code for NMO had a PPV of 47% across all sites, with significant site variation (0-77%). The best case-finding algorithm included at least 5 codes as well as a documented hospitalization (PPV = =90% for children and PPV = 92% for adults). Children were more likely to be evaluated by a rheumatologist or ophthalmologist, undergo magnetic resonance imaging of the orbits, and receive immunosuppressive and biologic agents than their adult counterparts. Rituximab was administered similarly among the two groups. CONCLUSION: The ICD-9 code for neuromyelitis optica (NMO) is inaccurate for identification of NMO/NMOSD. Using case-finding algorithms increases the PPV. The initial diagnostic evaluation and treatment of NMOSD differs significantly between children and adults.

4.
Biosens Bioelectron ; 148: 111800, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31678824

RESUMO

Circling exosomal PD-L1 can be expected as a predictor for the clinical responds of anti-PD-1/PD-L1 therapy. Here, we present a simple method integrating capture and analysis of exosomal PD-L1 directly from serum. Firstly, Fe3O4@TiO2 nanoparticles were used to enrich exosomes through the binding of TiO2 shell and hydrophilic phosphate head of the exosome phospholipids. Model exosomes can be enriched and separated from solution within 5 min with a capture efficiency of 96.5%. Secondly, anti-PD-L1 antibody modified Au@Ag@MBA SERS tags were added to label the exosomal PD-L1 for quantification. The whole process can be finished within 40 min with a detection limit of 1 PD-L1+exosome/µL. Furthermore, this method was used for personalized exosomal PD-L1quantification by using a 4 µL clinical serum sample individually. Based on the personalized SERS signal analysis, NSCLC patients can be distinguished from the healthy controls easily. More important, the advantage of clearly individual quantification may help the doctor to discover the relationship of exosomal PD-L1 and the immnuotherapy responds in individual level.

5.
Math Biosci Eng ; 16(6): 8309-8321, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31698669

RESUMO

An effective classifier combining convolutional neural network and regularized extreme learning machine (called as CNN-RELM) is presented in this paper. Firstly, CNN-RELM trains the convolutional neural network (CNN) using the gradient descent method until the learning target accuracy reaches. Then the fully connected layer of CNN is replaced by regularized extreme learning machine (RELM) optimized by genetic algorithm and the rest layers of the CNN remain unchanged. The experiments on different face databases are given to evaluate the performance of CNN-RELM. The experimental results show that CNN-RELM is a feasible classifier and it outperforms CNN and RELM. Due to the uniting of CNN and RELM, CNN-RELM have the advantages of CNN and RELM and it is easier to learn and faster in testing.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31671049

RESUMO

A Gram-staining-positive, aerobic, rod-shaped, non-spore-forming actinobacterium, designated strain M2KJ-4T, was isolated from a surface-sterilized bark of Melia azedaeach L. collected from Xinpu in Guizhou, PR China and characterized using a polyphasic approach to determine its taxonomic position. M2KJ-4T grew optimally with 1 % (w/v) NaCl at 25 °C and pH 8.0. Substrate mycelia and aerial mycelia were not formed, and no diffusible pigments were observed on the media tested. Phylogenetic analysis based on 16S rRNA gene sequence indicated that M2KJ-4Trepresented a member of the genus Aeromicrobium and shared the highest 16S rRNA gene sequence similarity with Aeromicrobium fastidiosum DSM 10552T (Z78209) (98.95 %). The DNA G+C content of M2KJ-4T was 70.6 mol%. The average nucleotide identity value and estimated DDH value between M2KJ-4T and the type strain of A. fastidiosum were 86.1 % and 30.2 %, respectively. The cell-wall peptidoglycan contained ll-diaminopimelic acid and MK-9(H4) was the predominant menaquinone. The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol, unidentified phospholipids and unidentified lipids. The major fatty acids were C16 : 0, 10-methyl C18 : 0, C16 : 0 2-OH and C18 : 1ω9c. On the basis of the results from phylogenetic, phenotypic and chemotaxonomic analysis, strain M2KJ-4T represents a novel species of the genus Aeromicrobium, for which the name Aeromicrobium endophyticum sp. nov. is proposed. The type strain is M2KJ-4T (=KCTC 49174T=CGMCC 1.13666T).

7.
Transplantation ; 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31596739

RESUMO

MDSCs, a heterogeneous population of myeloid cells, are characterized by their immunosuppressive abilities through the secretion of various cytokines such as iNOS, NO, ROS, TGF-ß, and Arg-1. Accumulating evidence highlights its potential role in maintaining immune tolerance in solid organ and hematopoietic stem cell transplantation (HSCT). Mechanistically, MDSCs induced transplant tolerance is mainly dependent on direct suppression of allogeneic reaction or strengthened crosstalk between MDSCs and Treg or NKT cells. Adopted transfer of in vitro- or in vivo-induced MDSCs by special drugs therefore becomes a potential strategy for maintaining transplantation tolerance. In this review, we will summarize the previously published data regarding the role of MDSCs in the biology of transplantation tolerance and gain insights into the possible molecular mechanism governing this process.

8.
J Invest Surg ; : 1-8, 2019 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-31588822

RESUMO

Purpose: Practical training models can be a viable and effective educational tool that allows surgeons to acquire specific surgical techniques or skills. However, a suitable animal training model for reconstruction after a pancreaticoduodenectomy (PD) has not yet been reported. Therefore, we explored the feasibility and safety of establishing an animal training model for digestive tract reconstruction after a simulated PD using mongrel dogs. Methods: We used the anatomical similarity between the canine and human digestive tract to simulate the digestive tract reconstruction after pancreatoduodenectomy. A hepatobiliary surgeon performed simulated PD digestive reconstructions on 6 mongrel canines. Pancreaticojejunostomy (PJ), biliary-enteric anastomosis (BEA), and jejuno-jejunal anastomosis (JJ) were performed sequentially. The survival rate, surgical operation time, complications, body weight changes, gross specimen, and pathological examination of the anastomotic region were observed 30 days after surgery. Results: The survival rate 30 days after surgery was 100%. Total mean operative time was 230.5 ± 39.7 min. The operative time for PJ, BEA, and JJ was calculated as 21.5 ± 7 min, 21.7 ± 8.7 min, and 13.2 ± 1.8 min, respectively. An incision infection occurred in 1 case (16.7%); there was 1 case of ascites (16.7%), and 1 case of vomiting (16.7%). The total protein and total bilirubin indicators of the 6 dogs and the serum amylase index of 5 dogs 30 days postoperatively were within the normal range. The 6th dog's serum amylase was approximately double the normal value, possibly due to pancreatitis. Observing the gross specimen, the mucosa of the anastomosis was intact and smooth. Masson staining showed that the bile duct and jejunum anastomosis, the pancreas, and jejunum of the 6 canines were all integrated with rich collagen. Conclusion: Establishing an animal model for digestive tract reconstruction after a simulated PD in canines is feasible and safe.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31646743

RESUMO

OBJECTIVE: We aimed to estimate the incidence rate (IR) of psoriasis in children with inflammatory bowel disease (IBD), juvenile idiopathic arthritis (JIA), and chronic noninfectious osteomyelitis (CNO) with tumor necrosis factor-alpha inhibitor (TNFi) exposure as compared to those without TNFi exposure and to the general pediatric population. METHODS: This was a single-center retrospective cohort study of children with IBD, JIA, or CNO from 2008 to 2018. TNFi exposure was defined as a prescription for adalimumab, etanercept, infliximab, certolizumab, or golimumab, and the primary outcome was incident psoriasis. IRs and standardized incidence ratios (SIRs) were calculated. Cox proportional hazards models were used to assess the association of psoriasis with TNFi exposure and other risk factors. RESULTS: Of the 4111 children who met inclusion criteria, 1614 (39%) had TNFi exposure and 2497 (61%) did not with 4705 and 6604 person-years of follow-up, respectively. There were 58 (IR 12.3 per 1000 person-years) and 25 (IR 3.8 per 1000 person-years) cases of psoriasis in children with and without TNFi exposure, respectively. The SIR was 18 (95% confidence interval [CI] 15, 22) overall, 30 (95% CI 23, 39) for children with TNFi exposure, and 9.3 (95% CI 6.3, 14) for children without TNFi exposure. The hazard ratio (HR) of psoriasis comparing TNFi exposure to no TNFi exposure was 3.84 (95% CI 2.28, 6.47, p<0.001). CONCLUSION: Children with IBD, JIA, and CNO had an increased rate of psoriasis compared to the general pediatric population, with the highest rate in those with TNFi exposure.

11.
J Am Heart Assoc ; 8(20): e012052, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31595836

RESUMO

Background The impact of estimated glomerular filtration rate (eGFR) on clinical short-term outcomes after stroke thrombolysis with tissue plasminogen activator remains controversial. Methods and Results We analyzed 18 320 ischemic stroke patients who received intravenous tissue plasminogen activator at participating hospitals in the Chinese Stroke Center Alliance between June 2015 and November 2017. Multivariate logistic regression models were used to evaluate associations between eGFR (<45, 45-59, 60-89, and ≥90 mL/min per 1.73 m2) and in-hospital mortality and symptomatic intracerebral hemorrhage, adjusting for patient and hospital characteristics and the hospital clustering effect. Of the 18 320 patients receiving tissue plasminogen activator, 601 (3.3%) had an eGFR <45, 625 (3.4%) had an eGFR 45 to 59, 3679 (20.1%) had an eGFR 60 to 89, and 13 415 (73.2%) had an eGFR ≥90. As compared with eGFR ≥90, eGFR values <45 (6.7% versus 0.9%, adjusted odds ratio, 3.59; 95% CI, 2.18-5.91), 45 to 59 (4.0% versus 0.9%, adjusted odds ratio, 2.00; 95% CI, 1.18-3.38), and 60 to 89 (2.5% versus 0.9%, adjusted odds ratio, 1.67; 95% CI, 1.20-2.34) were independently associated with increased odds of in-hospital mortality. However, there was no statistically significant association between eGFR and symptomatic intracerebral hemorrhage. Conclusions eGFR was associated with an increased risk of in-hospital mortality in acute ischemic stroke patients after treatment with tissue plasminogen activator. eGFR is an important predictor of poststroke short-term death but not of symptomatic intracerebral hemorrhage.

12.
Curr Drug Metab ; 2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31608839

RESUMO

Background: To investigate MiRNA-126 amounts in serum exosomes from allergic asthma patients as well as lung tissues of asthmatic mice, evaluating the expression of its target gene DNMT1 in mouse specimens. Methods: MiRNA-126 amounts in serum exosomes from asthmatic patients were detected by real-time PCR. The mouse model of allergic asthma was established by OVA-sensitization, and allergic symptoms were recorded; serum IL-4 and sIgE level evaluation (ELISA), alveolar lavage fluid (BALF) cell count and H&E staining were performed to assess airway inflammation. MiRNA-126 and DNMT1 levels in the lung of asthmatic and control mice were detected by real-time PCR; DNMT1 protein levels were detected by immunoblot. Results: MiRNA-126 amounts in peripheral blood exosomes from patients with allergic asthma were significantly higher than that of healthy volunteers (P<0.05). The frequencies of scratching of both sides of the nose and sneezing were elevated within 10 min of excitation in asthmatic rats compared with controls. Meanwhile, OVA-sIgE and IL-4 levels were significantly higher in asthmatic animals than controls (P<0.05). In the asthma group, narrowed bronchial lumen and thickened wall were observed, and bronchial and peripheral vessels showed overt inflammatory cell infiltration. Eosinophil, neutrophil and mast cell amounts in the BALF of asthmatic mice were significantly higher than control values. Furthermore, lung miRNA-126 expression in asthmatic mice was significantly higher than that of controls. Finally, DNMT1 mRNA and protein levels were significantly lower in asthmatic animals compared with controls (P < 0.01). Conclusion: MiRNA-126 is highly expressed in serum exosomes from allergic asthma patients and lung tissues of asthmatic mice, suggesting that it may be involved in the pathogenesis of bronchial asthma.

13.
Neurosci Lett ; 714: 134502, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31639423

RESUMO

The aim of this study was to investigate the relationship of dopamine D1 receptor (D1R) and its downstream factors with morphine withdrawal symptoms in rats. Rats were injected intraperitoneally with morphine in a dose-escalating manner. The midbrain periaqueductal gray (PAG) area was microinjected with D1R antagonist SCH23390 or D1R agonist SKF38393. Rats were intraperitoneally injected with naloxone (4 mg/kg) after the last morphine injection, and the withdrawal response was observed. The D1R antagonist reduced the withdrawal response in morphine-exposed rats and decreased the expression of Ca2+/calmodulin-dependent protein kinase II (CaMKII), phosphorylated extracellular signal-regulated kinase (p-ERK) and cAMP response element-binding protein (CREB) in the PAG. However, the ability of SKF38393 to increase the withdrawal response was weak and limited. Taken together, the results suggest that D1R antagonist decreased the withdrawal response in morphine-exposed rats by downregulating the downstream factors, CaMKII, p-ERK and CREB.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31613744

RESUMO

A Gram-staining-positive, aerobic, rod-shaped, endospore-forming bacterium, designated strain M5HDSG1-1T, was originally isolated from a surface-sterilized root of Taxus chinensis (Pilger) Rehd. in Guizhou, PR China. This bacterium was tested by a polyphasic approach to determine its taxonomic position. A 16S rRNA gene-based phylogenetic analysis revealed that M5HDSG1-1T had the greatest similarity to the type strain of Bacillus nealsonii DSM 15077T (99.1 %). The average nucleotide identity values between M5HDSG1-1T and Bacillus nealsonii DSM 15077T and Bacillus circulans NBRC 13626T were 73.3 and 72.8 %, respectively. The digital DNA-DNA hybridization values between M5HDSG1-1T and Bacillus nealsonii DSM 15077T and Bacillus circulans NBRC 13626T were 20.1 and 20.6 %, respectively, which were below the recommended thresholds. M5HDSG1-1T grew at a pH range of 6.0-12.0 (optimum, 7.0-8.0), at temperatures between 10 and 45 °C (optimum, 30 °C) and at 0-2 % (w/v) NaCl (optimum, 1 %). Neither substrate nor aerial mycelia was formed, and no diffusible pigments were observed on the media tested. The predominant isoprenoid quinone was menaquinone-7 (MK-7). The major fatty acids were anteiso-C15 : 0, and iso-C15 : 0. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminophospholipid and an unidentified phospholipid. The DNA G+C content was 37.5 mol%. According to the phylogeneic, phenotypic and chemotaxonomic data, M5HDSG1-1T was clearly distinguishable from other species with validly published names in the genus Bacillus and should therefore be classified as representing a novel species, and we suggest the name Bacillus taxi sp. nov. The type strain is M5HDSG1-1T (=JCM 33117T=CGMCC 1.13668T).

15.
Cell Mol Life Sci ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31584127

RESUMO

In the past two decades, transmembrane channel-like (TMC) proteins have attracted a significant amount of research interest, because mutations of Tmc1 lead to hereditary deafness. As evolutionarily conserved membrane proteins, TMC proteins are widely involved in diverse sensorimotor functions of many species, such as hearing, chemosensation, egg laying, and food texture detection. Interestingly, recent structural and physiological studies suggest that TMC channels may share a similar membrane topology with the Ca2+-activated Cl- channel TMEM16 and the mechanically activated OSCA1.2/TMEM63 channel. Namely, these channels form dimers and each subunit consists of ten transmembrane segments. Despite this important structural insight, a key question remains: what is the gating mechanism of TMC channels? The major technical hurdle to answer this question is that the reconstitution of TMC proteins as functional ion channels has been challenging in mammalian heterologous systems. Since TMC channels are conserved across taxa, genetic studies of TMC channels in model organisms such as C. elegans, Drosophila, and zebrafish may provide us critical information on the physiological function and regulation of TMCs. Here, we present a comparative overview on the diverse functions of TMC channels in different species.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31659889

RESUMO

Operating chemical looping at moderate temperatures circumvents the issue that the sintering of oxygen carrier materials (OCMs) is serious at typical operating conditions, 800-950 oC. However, lower temperatures can lead to deterioration on the reaction kinetics and thereby the low H2 production rate and yield. Here, we present several doped spinel oxides consisting of earth-abundant elements for chemical looping water splitting. By virtue of the ability of Cu dopant to improve the reduction of Co based binary spinel, the high reducibility of the dopants in the reduction period, as well as the phase reversibility in the water splitting period, Cu0.25Co0.25Fe2.5Oy shows high hydrogen yield (~11.9 mmol.g-1) and average hydrogen production rate (~137.7 µmol.g-1.min-1) at 550 oC, with negligible decays in repetitive redox cycles. The performance of this material is comparable to the state-of-the-art perovskites which usually contains rare-earth metals, enabling its potential in industrial implementation.

17.
Int Forum Allergy Rhinol ; 9(11): 1289-1296, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31623025

RESUMO

BACKGROUND: The therapeutic efficacy of allergic rhinitis (AR) needs to be improved. Probiotics have immunoregulatory functions. In this study we evaluated the effects of protein extracts of probiotics in the amelioration of AR. METHODS: Extracts of Bifidobacterium infantis (EBI) were prepared by lysing the live probiotics. AR mice were developed to be used to evaluate the therapeutic efficacy of EBI. RESULTS: The results show that EBI induced interleukin (IL)-10-producing dendritic cells (DCs) via increasing IL-35 and signal transducer and activator of transcription 3 (STAT3) phosphorylation. IL-10-expressing DCs induced IL-10-producing B cells (B10 cells), with the latter showing immunosuppressive functions. After challenge with specific antigens, AR mice showed sneezing, nasal itch, and increases in serum-specific immunoglobulin E (IgE) and mouse mast cell protease-1; higher levels of T helper 2 (Th2) cytokines (IL-4, 67.17 ± 10.66; IL-5, 62.83 ± 9.70; IL-13, 51.00 ± 6.69, before treatment) in nasal mucosal protein extracts, which were significantly suppressed (IL-4, 27.00 ± 6.66; IL-5, 23.86 ± 4.53; IL-13, 25.67 ± 4.93, after treatment (p < 0.001) by administration with EBI nasal drops. CONCLUSION: EBI can suppress AR via inducing B10 cells. Thus, after carrying out required preclinical experiments and tests, EBI has the translational potential to be used in the treatment of AR and other allergic diseases.

18.
Inorg Chem ; 58(21): 14389-14402, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31625736

RESUMO

Cation ordering/disordering in spinel oxides plays an essential role in the rich physical and chemical properties which are hallmarks of the structural archetype. A variety of cation-ordering motifs have been reported for spinel oxides with multiple cations residing on the octahedral site (or B-site). This has attracted tremendous attention from both experimental and theoretical communities in the last few decades. However, no unified view has been reached, presumably due to the richness of cation species and corresponding complex arrangements emergent in this large family of compounds. In this report, local cation-ordered ground states of (inverse) spinel oxides with two different cations on the octahedral site have been thoroughly investigated using neutron and X-ray total scattering, and a comprehensive theory has been proposed to explain the commonly observed cation-ordered polymorphs. It is found that a cation-zigzag-ordered structure (space group P4122) is the ground state for inverse spinel oxides with a pure or strong ionic lattice, while a cation-linear-ordered arrangement (space group Imma) emerges when one of the B-site cations forms very strong directional covalent bonds with lattice oxygen. The degree and length scale of cation ordering is strongly correlated with the charge and ionic radius difference between the two octahedral site cations. More complicated cation ordering schemes can be formed when there is a concomitant charge and orbital ordering which fall on a similar energy scale. This can lead to the formation of orbital-driven cation clusters or the broad concept of "molecules" in solid- state compounds. It is expected these findings will help to better understand the observed physical properties of spinel oxides and thus facilitate design strategies for improved functional materials.

19.
Biol Open ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31649117

RESUMO

Microbes in soil can degrade insoluble inorganic and organic phosphorus, which are components of the soil phosphorus cycle and play an important role in plant growth. Pinus massoniana is a pioneer tree species used for afforestation in southern China and grows in poor, acidic soil. A shortage of available phosphorus in soil limits the growth of P massoniana To alleviate this situation, it is necessary to improve soil fertility. A fungal strain (JP-NJ2) with the ability to solubilize phosphate was isolated from the P massoniana rhizosphere. The ability of JP-NJ2 to solubilize inorganic and organic phosphorus and promote the growth of P massoniana was evaluated. It showed that JP-NJ2 could grow in NBRIP inorganic phosphate (AlPO4, FePO4·4H2O, and Ca3[PO4]2) fermentation broths, with the highest phosphorus concentration (1.93 mg/mL) and phosphate-solubilizing rate (43.7%) for AlPO4 and in Monkina organic phosphate fermentation broth with a phosphorus concentration of 0.153 mg/mL. The phosphate-solubilizing capability in inorganic and organic fermentation broths was negatively correlated with pH. JP-NJ2-produced acids at a total concentration of 4.7 g/L, which included gluconic (2.3 g/L), oxalic (1.1 g/L), lactic (0.7 g/L), and malonic (0.5 g/L) acids. It prioritized extracellular acidic phosphatase and combined with phytase to solubilize organic phosphates. The fungal suspension and extracellular metabolites from phosphate-solubilizing fungi promoted the shoot length of P massoniana seedlings by 97.7% and 59.5%, respectively, while increased the root crown diameter by 46.8% and 27.7%. JP-NJ2 was identified as Penicillium guanacastense based on its morphology and phylogenetic analyses of five genes/regions (ITS, ben A, cmd, cox1, and tef). This is the first report on P guanacastense isolated from pine tree rhizosphere soil in China and its high phosphate-solubilization capability, which promoted the growth of P massoniana P guanacastense JP-NJ2 has potential use as a biological fertilizer in forestry and farming.

20.
Environ Int ; 133(Pt A): 105170, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31629171

RESUMO

Ecosystem health assessment is an important method for obtaining information on ecosystem conditions, and it plays a vital role in preserving and enhancing ecosystem health status. In addition, it provides useful information and knowledge for urban agglomeration development decision makers. However, ecological phenomena often vary considerably from one observation to the next, which makes it difficult to distinguish different status of the ecosystem health. In this study, hidden Markov model (HMM) was employed to simulate the internal-external correlations of ecosystem status through establishing the relationships between internal ecological health level and combination state of external observation. Based on the statistics and land use data in 2001, 2007 and 2013, the Vigor-Organization-Resilience (VOR) framework was employed to identify the ecosystem health in Shanghai-Hangzhou Bay Metropolitan (SHBM), in which the ecosystem health state was considered as a hidden state that could be estimated according to the conditions of vigor, organization and resilience. In addition, two parameter learning cases including mathematical statistics and extensible sequence method were employed to solve the iterative convergence problem of parameters in short-time series of ecosystem health simulation. Results show that HMM not only provides a comparable descriptive ability to that of the VOR model, but also can monitor ecosystem health at the optimal grid scale in SHBM. The combination of HMM and VOR greatly expands the spatiotemporal characteristics and provides a new research approach for the study of ecosystem health assessment of urban agglomerations.

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