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1.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3312-3315, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602888

RESUMO

Phytochemical investigation of the flowers of Hosta plantaginea led to isolate of one new flavonoid glycoside,plantanone C( 1) by silica gel,Sephadex LH-20,and RP-HPLC column chromatographies. Its structure was extensively determined on basis of HR-ESI-MS and NMR spectroscopic data. Compound 1 exhibited moderate antioxidant activity against DPPH radical scavenging activity,with an IC50 value of 240. 2 µmol·L~(-1).

2.
Sensors (Basel) ; 19(19)2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31547206

RESUMO

BaTiO3 (BTO) ceramics were fabricated based on stereolithography technology. The microstructures and electric properties of the BTO ceramics were studied. X-ray patterns of sintered BTO ceramics indicated that the tetragonal phase had formed, and the grain size increased clearly as BTO weight percentage increased. Moreover, the BTO ceramics exhibited good electric properties, with a piezoelectric constant d33 of 166 pC/N at 80% BTO weight percentage. To evaluate the properties of 3D printed BTO ceramics, a 1.4 MHz focused ultrasonic array was fabricated and characterized. The -6dB bandwidth of the array was 40%, and the insertion loss at the center frequency was 50 dB. The results show that the printed BTO ceramics array have good potential to be used in ultrasonic transducers for various applications.

3.
Proc Natl Acad Sci U S A ; 116(39): 19258-19263, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31501328

RESUMO

Ultrafast control of magnetic order by light provides a promising realization for spintronic devices beyond Moore's Law and has stimulated intense research interest in recent years. Yet, despite 2 decades of debates, the key question of how the spin angular momentum flows on the femtosecond timescale remains open. The lack of direct first-principle methods and pictures for such process exacerbates the issue. Here, we unravel the laser-induced demagnetization mechanism of ferromagnetic semiconductor GaMnAs, using an efficient time-dependent density functional theory approach that enables the direct real-time snapshot of the demagnetization process. Our results show a clear spin-transfer trajectory from the localized Mn-d electrons to itinerant carriers within 20 fs, illustrating the dominant role of [Formula: see text] interaction. We find that the total spin of localized electrons and itinerant carriers is not conserved in the presence of spin-orbit coupling (SOC). Immediately after laser excitation, a growing percentage of spin-angular momentum is quickly transferred to the electron orbital via SOC in about 1 ps, then slowly to the lattice via electron-phonon coupling in a few picoseconds, responsible for the 2-stage process observed experimentally. The spin-relaxation time via SOC is about 300 fs for itinerant carriers and about 700 fs for Mn-d electrons. These results provide a quantum-mechanical microscopic picture for the long-standing questions regarding the channels and timescales of spin transfer, as well as the roles of different interactions underlying the GaMnAs demagnetization process.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31512996

RESUMO

BACKGROUND: Forkhead box C1 (FOXC1) is an important cancer associated gene in tumor. PPAR-γ and C/EBPα are both transcriptional regulators involved in tumor development. OBJECTIVE: We aimed to clarify the function of PPAR-γ, C/EBPα in hepatocellular carcinoma (HCC) and relationship of PPAR-γ, C/EBPα and FOXC1 in HCC. METHOD: Western blotting, immunofluorescent staining and immunohistochemistry were used to evaluate protein expression. qRT-PCR was used to assess mRNA expression. Co-IP was performed to detect the protein interaction. And ChIP and fluorescent reporter detection were used to determine the binding between protein and FOXC1 promoter. RESULTS: C/EBPα could bind to FOXC1 promoter and PPAR-γ could strengthen C/EBPα's function. Expressions of C/EBPα and PPAR-γ were both negatively related with FOXC1 in human HCC tissue. Confocal displayed that C/EBPα was co-located with FOXC1 in HepG2 cells. C/EBPα could bind to FOXC1 promoter by ChIP. Luciferase activity detection exhibited that C/EBPα could inhibit FOXC1 promoter activity, especially FOXC1 promoter from -600 to -300 was the critical binding site. Only PPAR-γ couldn't influence luciferase activity but strengthen inhibited effect of C/EBPα. Further, the Co-IP displayed that PPAR-γ could bind to C/EBPα. When C/EBPα and PPAR-γ was both high expressed, cell proliferation, migration, invasion and colony information were inhibited enormously. C/EBPα plasmid combined with or without PPAR-γ agonist MDG548 treatment exhibited a strong tumor inhibition and FOXC1 suppression in mice. CONCLUSION: Our data establish C/EBPα targeting FOXC1 as potential determinant in the HCC, which supplies a new pathway to treat HCC. However, PPAR-γ has no effect on FOXC1 expression.

5.
Math Biosci Eng ; 16(5): 4053-4068, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31499649

RESUMO

In this paper, a low distortion reversible database watermarking method based on histogram gap is proposed in view of the large gap in histogram of database integer data. By using the method, the tolerance of the attribute column containing all integer data is firstly calculated and the prediction error is obtained according to the tolerance. Then according to the watermark bits to be embedded, the database tuples will be randomly grouped and the histogram can be constructed by using the prediction error. Finally, the histogram correction rule is used to find the histogram peak bin, the number of consecutive non-zero prediction errors on the left and right sides of the peak is obtained, and the histogram shift is performed on the side with a smaller number of non-zero prediction errors, and then the watermark embedding will be realized. The results of the experiments based on the published dataset of FCTD (Forest Cover Type Dataset) show that compared with the existing GAHSW which also considers distortion, the proposed method significantly reduces the number of histogram column shift while embedding the watermarks, greatly reduces the changes to the carrier data, and effectively reduces the database's data distortion caused by watermark embedding.

6.
Math Biosci Eng ; 16(5): 4908-4922, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31499696

RESUMO

Steganography poses a serious challenge to forensics because investigators cannot identify even traces of secret messages embedded using a steganographer. Contrarily, the objective of locating steganalysis is to locate the embedded message, which should help extract the secret message. In this paper, a methodology of locating steganalysis using quantitative steganalysis is presented for multiple stego images with embedded messages along the same embedding path. Three typical quantitative steganalysis methods are applied to the methodology to locate the messages embedded using LSB re-placement. Experimental results show that the presented methods can reliably estimate the embedding positions, which verifies the validity of the presented methodology. The presented methodology points out a new use of quantitative steganalysis, and further demonstrates that it is necessary to design more precise quantitative steganalysis methods.

7.
J Environ Manage ; 249: 109384, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31419674

RESUMO

The microalgal-bacterial co-cultivation was adopted as an alternative in making microbial-based biofuel production to be more feasible in considering the economic and environmental prospects. Accordingly, the microalgal-bacterial symbiotic relationship was exploited to enhance the microbial biomass yield, while bioremediating the nitrogen-rich municipal wastewater. An optimized inoculation ratio of microalgae and activated sludge (AS:MA) was predetermined and further optimization was performed in terms of different increment ratios to enhance the bioremediation process. The nitrogen removal was found accelerating with the increase of the increment ratios of inoculated AS:MA, though all the increment ratios had recorded a near complete total nitrogen removal (94-95%). In light of treatment efficiency and lipid production, the increment ratio of 0.5 was hailed as the best microbial population size in accounting the total nitrogen removal efficiency of 94.45%, while not compromising the lipid production of 0.241 g/L. Moreover, the cultures in municipal wastewater had attained higher biomass and lipid productions of 1.42 g/L and 0.242 g/L, respectively, as compared with the synthetic wastewater which were only 1.12 g/L (biomass yield) and 0.175 g/L (lipid yield). This was possibly due to the presence of trace elements which had contributed to the increase of biomass yield; thus, higher lipid attainability from the microalgal-bacterial culture. This synergistic microalgal-bacterial approach had been proven to be effective in treating wastewater, while also producing useful biomass for eventual lipid production with comparable net energy ratio (NER) value of 0.27, obtained from the life-cycle analysis (LCA) studies. Thereby, contributing towards long-term sustainability and possible commercialization of microbial-based biofuel production.

8.
Environ Sci Technol ; 53(17): 10269-10278, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31386807

RESUMO

Understanding the sectoral contribution of emissions to fine particulate matter (PM2.5) offers information for air quality management, and for investigation of association with health outcomes. This study evaluates the contribution of different emission sectors to PM2.5 in 2013 for Canada using the GEOS-Chem chemical transport model, downscaled with satellite-based PM2.5. Despite the low population-weighted PM2.5 concentrations of 5.5 µg m-3 across Canada, we find that over 70% of population-weighted PM2.5 originates from Canadian sources followed by 30% from the contiguous United States. The three leading sectoral contributors to population-weighted PM2.5 over Canada are wildfires with 1.0 µg m-3 (17%), transportation with 0.96 µg m-3 (16%), and residential combustion with 0.91 µg m-3 (15%). The relative contribution to population-weighted PM2.5 of different sectors varies regionally with residential combustion as the leading contributor in Central Canada (19%), while wildfires dominate over Northern Canada (59%), Atlantic Canada (34%), and Western Canada (18%). The contribution from U.S. sources is larger over Central Canada (33%) than over Western Canada (17%), Atlantic Canada (17%), and Northern Canada (<2%). Sectoral trend analysis showed that the contribution from anthropogenic sources to population-weighted PM2.5 decreased from 7.1 µg m-3 to 3.4 µg m-3 over the past two decades.

9.
J Am Chem Soc ; 141(35): 13914-13922, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31394035

RESUMO

Multicomponent reactions are fundamentally different from two-component reactions, as multicomponent reactions can enable the efficient and step-economical construction of complex molecular scaffolds from simple precursors. Here, an unprecedented three-component direct C-H addition was achieved in the challenging meta-selective fashion. Fluoroalkyl halides and a wide range of alkenes, including vinylarenes, unactivated alkenes, and internal alkenes, were employed as the coupling partners of arenes in this strategy. The detailed mechanism presented is supported by kinetic isotope studies, radical clock experiments, and density functional theory calculations. Moreover, this strategy provided access to various fluoride-containing bioactive 1,1-diarylalkanes and other challenging synthetically potential products.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31436521

RESUMO

A Gram-stain-negative bacterial strain, designated JW-3T, was isolated from a soil sample collected from farmland in Yantai, Shandong Province, PR China. Cells of strain JW-3T are motile rods and strictly aerobic, showing catalase- and oxidase-positive reactions. Strain JW-3T could grow at 16-37 °C (optimum, 30 °C), at pH 6.0-9.0 (pH 7.0) and in the presence of 0-1 % (w/v) NaCl (0.5 %, in Luria-Bertani broth). The major fatty acids were summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c; 35.5 %), iso-C16 : 0 (16.7 %) and C12 : 0 (10.8 %). The major respiratory quinone was ubiquinone-8 (Q8). The polar lipids of strain JW-3T consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, four unidentified phospholipids, two unidentified lipids, two unidentified glycolipids and a partial unidentified aminophospholipid. Strain JW-3T was most closely related to Steroidobacter agariperforans KA5-BT with 97.67 % 16S rRNA gene sequence similarity. Results of phylogenetic analyses, based on 16S rRNA gene sequencing, showed that strain JW-3T forms a distinct phylogenic lineage within the genus Steroidobacter of the family Sinobacteraceae. The DNA G+C content of strain JW-3T was 62.57 mol%, based on its draft genome sequence. Average nucleotide identity values and digital DNA-DNA hybridization values for draft genomes, between strain JW-3T and strain KA5-BT, were 84.54 and 30.80 %, respectively. Based on its phenotypic, chemotaxonomic and molecular features, and DNA-DNA hybridization results, strain JW-3T represents a novel species of the genus Steroidobacter, for which the name Steroidobactersoli sp. nov. is proposed. The type strain is JW-3T (=CCTCC AB 2018184T=KCTC 62820T).

11.
Acta Biomater ; 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31401346

RESUMO

In the present study, a novel biodegradable Zn-0.8Cu coronary artery stent was fabricated and implanted into porcine coronary arteries for up to 24 months. Micro-CT analysis showed that the implanted stent was able to maintain structural integrity after 6 months, while its disintegration occurred after 9 months of implantation. After 24 months of implantation, approximately 28 ±â€¯13 vol% of the stent remained. Optical coherence tomography and histological analysis showed that the endothelialization process could be completed within the first month after implantation, and no inflammation responses or thrombosis formation was observed within 24 months. Cross-section analysis indicated that the subsequent degradation products had been removed in the abluminal direction, guaranteeing that the strut could be replaced by normal tissue without the risk of contaminating the circulatory system, causing neither thrombosis nor inflammation response. The present work demonstrates that the Zn-0.8Cu stent has provided sufficient structural supporting and exhibited an appropriate degradation rate during 24 months of implantation without degradation product accumulation, thrombosis, or inflammation response. The results indicate that the Zn-0.8Cu coronary artery stent is promising for further clinical applications. STATEMENT OF SIGNIFICANCE: Although Zn and its alloys have been considered to be potential candidates of biodegradable metals for vascular stent use, by far, no Zn-based stent with appropriate medical device performance has been reported because of the low mechanical properties of zinc. The present work presents promising results of a Zn-Cu biodegradable vascular stent in porcine coronary arteries. The Zn-Cu stent fabricated in this work demonstrated adequate medical device performance both in vitro and in vivo and degraded at a proper rate without safety problems induced. Furthermore, large animal models have more cardiovascular similarities as humans. Results of this study may provide further information of the Zn-based stents for translational medicine research.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31464658

RESUMO

A strictly aerobic, Gram-stain-negative, rod-shaped, yellow, non-spore-forming bacterial strain, designated P-25T, was isolated from soil collected in Yantai, Shandong Province, PR China. The temperature, pH and NaCl concentration ranges for the growth of strain P-25T were 10-37 °C (optimum, 28-30 °C), pH 6.0-9.0 (optimum, pH 7.5-8.0) and 0-4 % (w/v) (optimum, 1 % w/v), respectively. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain P-25T was most closely related to Pedobacter xixiisoli S27T (98.1 % 16S rRNA gene sequence similarity), followed by Pedobacter chitinilyticus CM134L-2T (97.2 %) and Pedobacter ureilyticus THG-T11T (97.1 %). The genomic DNA G+C content of strain P-25T based on its draft genome sequence was 38.1 %. MK-7 was the major respiratory quinone, and iso-C15 : 0, C16 : 1ω7c and/or C16 : 1ω6c (summed feature 3) and iso-C17 : 0 3-OH were the major fatty acids. The major polar lipids were phosphatidylethanolamine, one unidentified aminophospholipid, one unidentified phospholipid, two unidentified lipids, five unidentified aminolipids and two unidentified glycolipids. Average nucleotide identity values for the draft genomes between strain P-25T and strains S27T, CM134L-2T and THG-T11T were 81.8, 77.6 and 81.2 %, respectively, and the digital DNA-DNA hybridization (dDDH) values were 30.0, 19.2 and 27.6 %, respectively. Based on their phylogenetic and phenotypic characteristics, chemotaxonomic data, and dDDH results, strain P-25T is considered to represent a novel species of the genus Pedobacter, for which the name Pedobacter helvus sp. nov. is proposed; the type strain is strain P-25T (KCTC 62821T=CCTCC AB 2018185T).

13.
Am Surg ; 85(6): 645-653, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31267907

RESUMO

The purpose of this meta-analysis was to determine the value of quantitative dynamic contrast-enhanced (DCE) MRI (DCE-MRI) in evaluating the response of breast cancer to neoadjuvant chemotherapy (NAC). PubMed, Embase, and Cochrane Library databases (from building to July 31, 2018) were searched to collect articles about the therapeutic evaluation of NAC using the quantitative DCE-MRI in patients with breast cancer. The sensitivities and specificities of quantitative DCE-MRI in the evaluation of NAC for breast cancer were extracted from the articles. Meta-DiSc1.4 was applied to evaluate the efficacy of the sensitivity and specificity; forest figure and summary receiver operating characteristics (SROC) were created. A total of 356 articles were enrolled in this study, including 739 cases in total, in which 218 cases were effective and the other 521 cases were ineffective to NAC, considering the pathological results as the gold standard. The sensitivity and specificity in the included 14 articles of quantitative DCE-MRI (Ktrans, Kep, and ve) in comprehensively evaluating NAC for breast cancer were 84 per cent (95% confidence interval (CI): 78-88%) and 83 per cent (95% CI: 79-86%), respectively. The area under SROC was 0.899 (95% CI: 0.867-0.943). The sensitivity and specificity in the three articles of Ktrans evaluating NAC for breast cancer were 84.1 per cent (95% CI: 71.0-92.1%) and 81.3 per cent (95% CI: 70.5%-88.5%), respectively. The area under SROC was 0.899 (95% CI: 0.834-0.962). Our study confirmed that the quantitative DCE-MRI is able to monitor NAC treatment for breast cancer because of its high sensitivity and specificity. However, there is a high degree of heterogeneity in published studies, highlighting the lack of standardization in the field.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Meios de Contraste , Imagem por Ressonância Magnética/métodos , Terapia Neoadjuvante/métodos , Intensificação de Imagem Radiográfica/métodos , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Área Sob a Curva , Neoplasias da Mama/mortalidade , Estudos de Avaliação como Assunto , Medicina Baseada em Evidências , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC , Medição de Risco , Sensibilidade e Especificidade , Análise de Sobrevida , Resultado do Tratamento
14.
Bioresour Technol ; 289: 121727, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31279318

RESUMO

In this present study, microalgal phycobiliproteins were isolated and purified via potential biphasic processing technique for pharmaceutical as well as food applications. The algal pre-treatment techniques were studied to enhance the yield of microalgal phycobiliproteins from the biomass. The proposed methods were optimised to obtain the best recovery yield of phycobiliproteins that can be isolated from the biomass. The phycobiliproteins were further purified using liquid biphasic system. The results showed that microalgal phycobiliproteins of high purity and yield was achieved using sonication treatment (20% power, 50% duty cycle and 7 min of irradiation time) with the biphasic system, where the purification fold of 6.17 and recovery yield of 94.89% was achieved. This work will provide insights towards the effective downstream processing of biomolecules from microalgae.


Assuntos
Microalgas , Preparações Farmacêuticas , Spirulina , Biomassa , Ficobiliproteínas
15.
J Food Biochem ; 43(4): e12771, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31353584

RESUMO

Low-temperature storage is a key method for delaying the ripening of "Nanguo" pears. However, the aroma of "Nanguo" pears fades after long-term refrigeration. We investigated the potential mechanism of fading of aroma in "Nanguo" pears by analyzing differentially expressed proteins in pears stored at room temperature, which had higher level of aromatic esters and those stored at low temperature, having lower esters. We observed that 293 kinds of proteins were down-regulated and 377 were up-regulated. Gene ontology analysis showed that proteins in the "catalytic activity," "metabolic process," "organelle," and "membrane" proteins were affected by low temperature. KEGG analysis showed that the differentially expressed proteins were involved in oxidative phosphorylation, carbon and fatty acid metabolism. Real-time PCR showed that transcription levels of nine selected genes correlated with differentially expressed proteins. The results revealed that the expression of potentially aroma-related proteins, which are important in further research on improving aroma quality of "Nanguo" pears. PRACTICAL APPLICATIONS: "Nanguo" pears aroma is an important character for attracting consumers and many proteins are involved in the synthesis of aroma. However, their aroma is lost after cold storage and the quality of fruits is affected by low temperature. It is, therefore, of great significance to study the potential proteins that regulate the aroma of refrigerated "Nanguo" pears. In addition, the study results could provide basic and scientific data for the study of improving the aroma quality and genetic improvement of "Nanguo" pears.

16.
Inorg Chem ; 58(15): 9706-9712, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31318540

RESUMO

A family of inorganic-organic hybrid one-dimensional (1-D) chain iron-lanthanide (Ln) heterometal encapsulated tungstotellurates [H2N(CH3)2]8K2Na4[Ln2(Ac)2(H2O)4Fe2(Hpdca)2(B-ß-TeW9O33)2][Ln2(H2O)8Fe2(Hpdca)2(B-ß-TeW9O33)2]·50H2O [Ln = Eu3+ (1), Tb3+ (2), Dy3+ (3), Er3+ (4), HAc = acetate acid, H2pdca = 2,5-pyridinedicarboxylic acid] were prepared using a facile "one-pot" reaction. The molecular structures of 1-4 consist of an intriguing organic-ligand-connecting Fe-Ln heterometal inserted tetrameric unit [Ln2(Ac)2(H2O)4Fe2(Hpdca)2(B-ß-TeW9O33)2][Ln2(H2O)8Fe2(Hpdca)2(B-ß-TeW9O33)2]14-. Appealingly, the tetrameric unit is composed of two sandwich-type subunits [Ln2(Ac)2(H2O)4Fe2(Hpdca)2(B-ß-TeW9O33)2]8- and [Ln2(H2O)8Fe2(Hpdca)2(B-ß-TeW9O33)2]6-, in which each sandwich-type subunit can be regarded as a derivative of two Ln-organic complexes substituting two external FeIII ions in the classic Krebs-type [Fe4(H2O)10(ß-TeW9O33)2]4- fragment. Furthermore, adjacent tetrameric units are interconnected into a 1-D chain arrangement by Hpdca- bridges. 1-4 represent the first examples of Fe-Ln heterometal encapsulated tungstotellurates. Comprehensive magnetic measurements of 3 imply the possible single-molecule magnet properties in 3 with an estimated relaxation time τ0 ≈ 6.06 × 10-6 s at Hdc = 0 Oe and τ0 ≈ 6.97 × 10-5 s at Hdc = 1500 Oe. In addition, the solid-state photoluminescence spectra of 1 and 2 at room temperature exhibit the typical f-f transitions of Ln cations. The Commission International d'Eclairage (CIE) color coordinates of (0.540 24, 0.442 44) for 1 and (0.428 71, 0.428 30) for 2 along with the correlated color temperatures of 1995 and 3278 K, dominant wavelengths of 586 and 578 nm, and color purities of 95.09% and 57.27% for 1 and 2 are obtained.

17.
Medicine (Baltimore) ; 98(28): e16404, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31305451

RESUMO

BACKGROUND: The role of fruit and vegetables (FVs) consumption in decreasing gallstone disease risk remains contradictory. We performed a meta-analysis to analyze this potential correlation, followed by investigation of dose-response relationship of FVs consumption with gallstone disease. MATERIALS AND METHODS: PubMed, Embase, as well as Web of Science were searched to determine all published researches about the connection of FVs consumption with gallstone disease before March 2018. Relative risks (RRs) or odds ratios (ORs) along with corresponding 95% confidence intervals (CIs) was pooled utilizing random effect models, aiming at examining the correlation of FVs consumption with gallstone disease risk. RESULTS: One cross-sectional study, our case-control studies as well as nine cohort studies were enrolled, covering approximately 33,983 patients with gallstone disease and 1,53,3752 participants. In a pooled analysis, vegetables consumption was significantly related to a decreased gallstone disease risk, (RR = 0.83, 95% CI, 0.74-0.94, I = 91.1%), and for fruits consumption, RR was similar (RR = 0.88, 95%CI, 0.83-0.92, I = 0.01%). This inverse correlation of FVs consumption with gallstone disease risk was solid in most subgroup analysis. The nonlinear dose-response correlation indicated that gallstone risk was reduced by 4% (RR = 0.96, 95%CI, 0.93-0.98) and 3% (RR = 0.97, 95%CI, 0.96-0.98) for every 200 g per day increment in vegetables consumption (P = .001) and fruits consumption (P = .001), respectively. CONCLUSION: This study suggests vegetables and fruits consumption is correlated with a significantly reduced risk of gallstone disease.


Assuntos
Dieta , Frutas , Cálculos Biliares/epidemiologia , Verduras , Cálculos Biliares/prevenção & controle , Humanos
18.
IEEE Trans Cybern ; 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31283492

RESUMO

This paper discusses the problem of suboptimal local piecewise H∞ fuzzy control of quasi-linear spatiotemporal dynamic systems with control magnitude constraints. A Takagi-Sugeno fuzzy partial differential equation (PDE) model with space-varying coefficient matrices is first assumed to be derived for exactly describing nonlinear system dynamics. In the light of the fuzzy model, a local piecewise fuzzy feedback controller is then constructed to guarantee the exponential stability with a prescribed H∞ disturbance attenuation level for the resulting closed-loop system, while the control constraints are also ensured. A sufficient condition on the existence of such fuzzy controller is developed by the Lyapunov direct method and an integral inequality and presented in terms of space algebraic linear matrix inequalities (LMIs) coupled with LMIs. By virtue of extreme value theorem, a suboptimal-constrained local piecewise H∞ fuzzy control design in the sense of minimizing the disturbance attenuation level is formulated as a minimization optimization problem with LMI constraints. Finally, the proposed method is applied to solve the feedback control of a quasi-linear FitzHugh-Nagumo equation with space-varying coefficients, and simulation results show its effectiveness and merit.

19.
Microb Cell Fact ; 18(1): 115, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253150

RESUMO

BACKGROUND: Ganoderic acids (GAs), derived from the medicinal mushroom Ganoderma lucidum, possess anticancer and other important pharmacological activities. To improve production of GAs, a homologous farnesyl diphosphate synthase (FPS) gene was overexpressed in G. lucidum. Moreover, the influence of FPS gene overexpression on GA production was investigated by developing the corresponding mathematical models. RESULTS: The maximum levels of total GAs and individual GAs (GA-T, GA-S, and GA-Me) in the transgenic strain were 2.76 mg/100 mg dry weight (DW), 41 ± 2, 21 ± 5, and 28 ± 1 µg/100 mg DW, respectively, which were increased by 2.28-, 2.27-, 2.62-, and 2.80-folds compared with those in the control. Transcription levels of squalene synthase (SQS) and lanosterol synthase (LS) genes during GA biosynthesis were upregulated by 2.28- and 1.73-folds, respectively, in the transgenic G. lucidum. In addition, the developed unstructured models had a satisfactory fit for the process of GA production in submerged cultures of G. lucidum. Analysis of the kinetic process showed that FPS gene overexpression had a stronger positive impact on GA production compared with its influence on cell growth. Also, FPS gene overexpression led to a higher non-growth-associated-constant ß (1.151) over the growth-associated-constant α (0.026) in the developed models. CONCLUSIONS: FPS gene overexpression is an effective strategy to improve the production of GAs in G. lucidum. The developed mathematical models are useful for developing a better GA production process in future large-scale bioreactors.

20.
Bioresour Technol ; 288: 121607, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31176945

RESUMO

In this study, the effects of strigolactone (SL) on the biomass, lipid content, biochemical properties, and gene transcription of Monoraphidium sp. QLY-1 were examined. The lipid content and lipid productivity increased by 61% and 55% in QLY-1 under 1 µM SL induction compared to the control group, respectively. SL also upregulated the levels of endogenous NO and Ca2+ and lipid biosynthesis gene transcription. Subsequently, the relationship between Ca2+ and nitric oxide (NO) in the regulation of cell growth and lipid accumulation of QLY-1 under SL induction conditions was analysed. An increase in endogenous Ca2+ regulated cell growth and lipid biosynthesis by modulating the levels of NO and lipid biosynthesis-related gene expression. Collectively, this study provided a valuable approach for biofuel production from microalgae under SL induction and demonstrated that there is crucial crosstalk between the Ca2+ and NO signalling in the manipulation of lipid biosynthesis in microalgae under SL treatment.


Assuntos
Microalgas , Biocombustíveis , Biomassa , Clorofíceas , Lipídeos
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