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1.
Sci Rep ; 14(1): 13821, 2024 06 15.
Article in English | MEDLINE | ID: mdl-38879683

ABSTRACT

The problem of cadmium pollution and its control is becoming increasingly severe issue in the world. Banana straw is an abundant bio raw material, but its burning or discarding in field not only causes pollution but also spreads fusarium wilt. The objective of this paper is to utilize biochar derived from the wilt-infected banana straw for remediation of Cd(II) pollution while to eliminate the pathogen. The activity of wilt pathogen in biochar was determined by PDA petri dish test. The Cd(II) adsorption of the biochar was determined by batch adsorption experiments. The effects of KOH concentration (0.25, 0.5 and 0.75 M) on the physicochemical characteristics of the biochar were also observed by BET, SEM, FTIR, XRD and XPS. Results showed that pristine banana straw biochar (PBBC) did not harbor any pathogen. The specific surface area (SSA) and Cd(II) adsorption capacity of 0.75 M KOH modified banana straw biochar (MBBC0.75M) were increased by 247.2% and 46.1% compared to that of PBBC, respectively. Cd(II) adsorption by MBBC0.75M was suitable to be described by the pseudo-second-order kinetic model and Freundlich isotherm. After Cd(II) adsorption, the CdCO3 were confirmed by XRD and observed through SEM. The weakness and shift of oxygen-containing functional groups in MBBC0.75M after Cd(II) adsorption implied that those groups were complexed with Cd(II). The results showed that pyrolysis could not only eliminate banana fusarium wilt, but also prepare porous biochar with the wilt-infected banana straw. The porous biochar possessed the potential to adsorb Cd(II) pollutants.


Subject(s)
Cadmium , Charcoal , Fusarium , Musa , Water Pollutants, Chemical , Musa/microbiology , Musa/chemistry , Charcoal/chemistry , Fusarium/metabolism , Cadmium/metabolism , Adsorption , Porosity , Plant Diseases/microbiology , Plant Diseases/prevention & control , Environmental Restoration and Remediation/methods , Kinetics
2.
Article in English | MEDLINE | ID: mdl-38828555

ABSTRACT

CONTEXT: Paltusotine is a nonpeptide selective somatostatin receptor 2 agonist in development as once-daily oral treatment for acromegaly. OBJECTIVE: To evaluate the efficacy and safety of paltusotine in the treatment of patients with acromegaly previously controlled with injected somatostatin receptor ligands (SRLs). METHODS: This phase 3, randomized, double-blind, placebo-controlled trial enrolled adults with acromegaly who had insulin-like growth factor I (IGF-I) ≤1.0 times the upper limit of normal (×ULN) while receiving a stable dose of depot octreotide or lanreotide. Patients were switched from injected SRLs and randomized to receive paltusotine or placebo orally for 36 weeks. The primary endpoint was proportion of patients maintaining IGF-I ≤1.0×ULN. Secondary endpoints were change in IGF-I level, change in Acromegaly Symptom Diary (ASD) score, and maintenance of mean 5-sample growth hormone (GH) <1.0 ng/mL. RESULTS: The primary endpoint was met: 83.3% (25/30) of patients receiving paltusotine and 3.6% (1/28) receiving placebo maintained IGF-I ≤1.0×ULN (odds ratio: 126.53; 95% CI: 13.73, >999.99; P<.0001). Paltusotine was also superior to placebo for all secondary endpoints: mean (±SE) change in IGF-I of 0.04±0.09×ULN versus 0.83±0.1×ULN (P<.0001); mean (±SE) change in ASD score of -0.6±1.5 versus 4.6±1.6 (P=.02); mean GH maintained at <1.0 ng/mL in 20/23 (87.0%) versus 5/18 (27.8%) patients (odds ratio: 16.61; 95% CI: 2.86, 181.36; P=.0003). The most common adverse events were acromegaly symptoms and gastrointestinal effects characteristic of SRLs. CONCLUSION: Replacement of injected SRLs by once-daily oral paltusotine was effective in maintaining both biochemical and symptom control in patients with acromegaly and was well tolerated.

3.
Small ; : e2312071, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38446075

ABSTRACT

The fabrication of metallic micro/nanostructures has great potential for advancing optoelectronic microdevices. Over the past decade, femtosecond laser direct writing (FsLDW) technology has played a crucial role in driving progress in this field. In this study, silica gel glass is used as a supporting medium, and FsLDW is employed to reduce gold and palladium ions using 7-Diethylamino-3-thenoylcoumarin (DETC) as a two-photon sensitizer, enabling the printing of conductive multilayered and 3D metallic structures. How the pore size of the silica gel glass affects the electrical conductivity of printed metal wires is systematically examined. This 3D printing method is versatile and offers expanded opportunities for applying metallic micro/nanostructures in optoelectronic devices.

4.
Chin J Traumatol ; 27(1): 34-41, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38071167

ABSTRACT

PURPOSE: To identify the potential target genes of blast lung injury (BLI) for the diagnosis and treatment. METHODS: This is an experimental study. The BLI models in rats and goats were established by conducting a fuel-air explosive power test in an unobstructed environment, which was subsequently validated through hematoxylin-eosin staining. Transcriptome sequencing was performed on lung tissues from both goats and rats. Differentially expressed genes were identified using the criteria of q ≤ 0.05 and |log2 fold change| ≥ 1. Following that, enrichment analyses were conducted for gene ontology and the Kyoto Encyclopedia of Genes and Genomes pathways. The potential target genes were further confirmed through quantitative real-time polymerase chain reaction and enzyme linked immunosorbent assay. RESULTS: Observations through microscopy unveiled the presence of reddish edema fluid, erythrocytes, and instances of focal or patchy bleeding within the alveolar cavity. Transcriptome sequencing analysis identified a total of 83 differentially expressed genes in both rats and goats. Notably, 49 genes exhibited a consistent expression pattern, with 38 genes displaying up-regulation and 11 genes demonstrating down-regulation. Enrichment analysis highlighted the potential involvement of the interleukin-17 signaling pathway and vascular smooth muscle contraction pathway in the underlying mechanism of BLI. Furthermore, the experimental findings in both goats and rats demonstrated a strong association between BLI and several key genes, including anterior gradient 2, ankyrin repeat domain 65, bactericidal/permeability-increasing fold containing family A member 1, bactericidal/permeability-increasing fold containing family B member 1, and keratin 4, which exhibited up-regulation. CONCLUSIONS: Anterior gradient 2, ankyrin repeat domain 65, bactericidal/permeability-increasing fold containing family A member 1, bactericidal/permeability-increasing fold containing family B member 1, and keratin 4 hold potential as target genes for the prognosis, diagnosis, and treatment of BLI.


Subject(s)
Lung Injury , Rats , Animals , Lung Injury/genetics , Goats/genetics , Keratin-4 , Gene Expression Profiling , Gene Expression
5.
Anal Chem ; 95(45): 16639-16648, 2023 11 14.
Article in English | MEDLINE | ID: mdl-37910128

ABSTRACT

The simultaneous detection of multiple antibiotic residues in food is of great significance for food safety. In this work, a novel dual-potential electrochemiluminescence (ECL) immunoassay was designed for the simultaneous detection of chloramphenicol and fluorfenicol residues in food. Ru@MOF was used as an anodic probe, and SnS2 QDs-PEI-Au-MoS2 was used as a cathodic probe. Notably, the coreactant for both luminophores was K2S2O8, avoiding interactions caused by different kinds of coreactants. Au nanoparticles functionalized with a nitrogen- and sulfur-doped graphene oxide-modified glassy carbon electrode to improve the electron transfer efficiency and provide a larger surface area for immobilization of antigen. The linear range for the detection of florfenicol was determined to be 0.1-1000 ng mL-1 with a detection limit of 0.03 ng mL-1, and the linear range for the detection of chloramphenicol was 0.01-1000 ng mL-1 with a detection limit of 3.2 pg mL-1 by recording the ECL responses at two different excitation potentials. The proposed immunoassay achieved a more stable recovery in the detection of actual samples and provided a new analytical method for the simultaneous detection of florfenicol and chloramphenicol residues with high sensitivity and specificity.


Subject(s)
Biosensing Techniques , Metal Nanoparticles , Chloramphenicol , Electrochemical Techniques/methods , Metal Nanoparticles/chemistry , Gold/chemistry , Immunoassay/methods , Luminescent Measurements/methods , Biosensing Techniques/methods , Limit of Detection
6.
Analyst ; 148(22): 5691-5697, 2023 Nov 06.
Article in English | MEDLINE | ID: mdl-37823327

ABSTRACT

In this study, a novel electrochemiluminescence resonance energy transfer (ECL-RET) immunoassay was developed for the first time for the detection of zearalenone (ZEN). A porphyrin metal-organic framework (PCN-222), an emerging porphyrin-based ECL luminophore, was prepared by a simple hydrothermal method using tetrakis(4-carboxyphenyl) porphyrin, which has excellent ECL emission as well as good ECL efficiency. Because the ECL emission spectrum of PCN-222 is highly matched to the absorption spectrum of gold nanoparticle-modified graphene oxide (AuNPs/NSG) nanocomposites, they were used as donor-acceptor counterparts in this work for the ECL-RET strategy. Under optimal conditions, the ECL immunosensor showed a sensitive response to ZEN in a wide detection range, with a linearity of 0.0005-1000 ng mL-1 and a detection limit of 0.15 pg mL-1. In addition, the sensor showed good potential for application in the detection of wheat and corn samples, providing a new approach for the detection of mycotoxin-like contaminants such as ZEN in food grains.


Subject(s)
Biosensing Techniques , Metal Nanoparticles , Metal-Organic Frameworks , Zearalenone , Immunoassay/methods , Gold , Biosensing Techniques/methods , Luminescent Measurements/methods , Energy Transfer
7.
Math Biosci Eng ; 20(6): 10883-10908, 2023 04 20.
Article in English | MEDLINE | ID: mdl-37322965

ABSTRACT

New stochastic and deterministic Hepatitis B epidemic models with general incidence are established to study the dynamics of Hepatitis B virus (HBV) epidemic transmission. Optimal control strategies are developed to control the spread of HBV in the population. In this regard, we first calculate the basic reproduction number and the equilibrium points of the deterministic Hepatitis B model. And then the local asymptotic stability at the equilibrium point is studied. Secondly, the basic reproduction number of the stochastic Hepatitis B model is calculated. Appropriate Lyapunov functions are constructed, and the unique global positive solution of the stochastic model is verified by Itô formula. By applying a series of stochastic inequalities and strong number theorems, the moment exponential stability, the extinction and persistence of HBV at the equilibrium point are obtained. Finally, using the optimal control theory, the optimal control strategy to eliminate the spread of HBV is developed. To reduce Hepatitis B infection rates and to promote vaccination rates, three control variables are used, for instance, isolation of patients, treatment of patients, and vaccine inoculation. For the purpose of verifying the rationality of our main theoretical conclusions, the Runge-Kutta method is applied to numerical simulation.


Subject(s)
Epidemics , Hepatitis B , Humans , Incidence , Hepatitis B/epidemiology , Hepatitis B/prevention & control , Hepatitis B virus , Computer Simulation
8.
Biotechnol Biofuels Bioprod ; 16(1): 97, 2023 Jun 08.
Article in English | MEDLINE | ID: mdl-37291654

ABSTRACT

BACKGROUND: Lignin played an important role in the establishment of coated fertilizers coating material as a substitute for petrochemical raw materials. However, so far, the lignin-based coated fertilizers was limited in only the poor slow-release performance. To achieve good slow-release performance of lignin-based coated fertilizers, hydrophilic of lignin need to be resolved to establish an green and better controllable lignin-based coated fertilizers. RESULTS: In the study, a novel green double layer coating with lignin-based polyurethane (LPU) as the inner coating and epoxy resin (EP) as the outer coating was effectively constructed for coated urea. Fourier transform infrared spectra confirmed that lignin and polycaprolactone diol successfully reacted with Hexamethylene diisocyanate. The loss weight and water contact angle (WCA, 75.6-63.6°) of the LPUs decreased with the increased lignin content. The average particle hardness of the lignin-based double-layer coated urea (LDCU) first increased from 58.1 N (lignin of 30%) to 67.0 N (lignin of 60%), but then decreased to 62.3 N (lignin of 70%). The release longevity of the coated urea was closely related to the preparation parameters of the coating material. The optimal cumulative nutrient release rate (79.4%) of LDCU was obtained (lignin of 50%, -CNO/-OH molar ratios of 1.15, EP of 35%, and coating ratio of 5%). The aggregates of hydrone on the LDCU caused the dissolution and swelling of nutrients, and then the diffusion of nutrients through the concentration gradient. CONCLUSIONS: A though the nutrient release of the LDCUs was affected by many factors, the successful development of the LDCUs will help improve the rapid development of the coated fertilizer industry.

9.
Int J Biol Macromol ; 242(Pt 3): 125143, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37247714

ABSTRACT

Natural bioactive molecules have been widely used as stabilizers in the functional improvement of selenium nanoparticles (SeNPs) in recent years. In this study, Morchella sextelata polysaccharide (MSP) was introduced as a novel stabilizer for the synthesis of SeNPs based on the redox system of sodium selenite and ascorbic acid. The size, morphology, stability, and anti-cancer cell activities were respectively analyzed by various methods. The results showed that the synthesized SeNPs with MSP were 72.07 ± 0.53 nm in size, red in color, spherical in shape, and amorphous in nature. MSP-SeNPs showed high scavenging activity against DPPH and ABTS radicals. And, these MSP-SeNPs exhibited a significant anti-proliferation effect on human liver (HepG2) and cervical cancer (Hela) cells in vitro, while no significant cytotoxicity against normal human kidney cells (HK-2) was observed. Moreover, the mitochondria-dependent apoptosis pathway triggered by MSP-SeNPs in HepG2 cell was identified. The expression levels of p53, Bax, cytochrome c, caspase-3 and caspase-9 were all up-regulated in HepG2 cells after MSP-SeNPs treatment, while Bcl-2 expression was down-regulated. These results suggest that MSP-SeNPs have strong potential as the food supplement for application in cancer chemoprevention.


Subject(s)
Nanoparticles , Selenium , Humans , Selenium/pharmacology , Selenium/chemistry , Nanoparticles/chemistry , Antioxidants/chemistry , Polysaccharides/pharmacology
10.
Biotechnol Genet Eng Rev ; : 1-15, 2023 Apr 11.
Article in English | MEDLINE | ID: mdl-37042058

ABSTRACT

The curative effect of Huoxue Huayu Recipe combined with ibuprofen in the postoperative pain in patients with ankle fractures was analyzed. 68 patients with ankle fractures were divided into study group (n = 34, Huoxue Huayu Decoction combined with ibuprofen) and control group (n = 34, ibuprofen). The levels of inflammatory factors, ankle joint function, VAS score and bone metabolism indexes were compared. Complications, isokinetic muscle strength and clinical related index levels were compared after treatment. High AOFAS score and low VAS score were identified in the study group compared with the control group at 1 week, 1 month and 2 months after operation. Compared to the control group, the incidence of postoperative complications was declined in the study group. After treatment, IL-6 and TNF-α levels in both groups were significantly decreased, and the study group had lower IL-6 and TNF-α levels. After treatment, the torque acceleration energy, relative peak torque value and endurance in the study group were obviously improved. The disappearance time of swelling and pain, fracture healing time, and complete weight-bearing time in the study group were reduced compared to the control group. After treatment, BGP and BALP levels in study group were higher than control group. Huoxue Huayu Recipe combined with ibuprofen can reduce inflammatory factors levels in patients with ankle fracture, improve isokinetic muscle strength and ankle function, and accelerate the recovery of patients.

11.
Math Biosci Eng ; 20(3): 4421-4436, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36896506

ABSTRACT

The purpose of this article is to research the existence of solutions for fractional periodic boundary value problems with p(t)-Laplacian operator. In this regard, the article needs to establish a continuation theorem corresponding to the above problem. By applying the continuation theorem, a new existence result for the problem is obtained, which enriches existing literature. In addition, we provide an example to verify the main result.

12.
Math Biosci Eng ; 20(3): 5094-5116, 2023 Jan 06.
Article in English | MEDLINE | ID: mdl-36896537

ABSTRACT

The purpose of the article is to investigate Dirichlet boundary-value problems of the fractional p-Laplacian equation with impulsive effects. By using the Nehari manifold method, mountain pass theorem and three critical points theorem, some new results are achieved under more general growth conditions. In addition, this paper weakens the commonly used p-suplinear and p-sublinear growth conditions.

13.
Sci Total Environ ; 873: 162334, 2023 May 15.
Article in English | MEDLINE | ID: mdl-36813204

ABSTRACT

Aminated lignin (AL) was prepared and first applied to remediation of cadmium (Cd) pollution in soil. Meanwhile, the nitrogen mineralization characteristics of AL in soil and its effect on soil physicochemical properties were elucidated by soil incubation experiment. The results showed that the Cd availability was dramatically lowered in soil by adding the AL. The DTPA-extractable Cd content of AL treatments was considerably reduced by 40.7-71.4 %. The soil pH (5.77-7.01) and absolute value of zeta potential (30.7-34.7 mV) enhanced simultaneously as the AL additions increased. The content of soil organic matter (SOM) (99.0-264.0 %) and total nitrogen (95.9-301.3 %) were gradually enhanced due to high C (63.31 %) and N (9.69 %) content in AL. Moreover, AL significantly elevated the content of mineral nitrogen (77.2-142.4 %) and available nitrogen (95.5-301.7 %). The first-order kinetic equation of soil nitrogen mineralization revealed that AL greatly enhanced nitrogen mineralization potential (84.7-143.9 %) and reduced environmental pollution by lowering the loss of soil inorganic nitrogen. AL could effectively reduce the availability of Cd through direct (self-adsorption) and indirect effects (improvement of soil pH, SOM and reduction of soil zeta potential), thereby achieving passivation of Cd in soil. In short, this work will develop a novel approach and technical support for soil heavy metal remediation, which is of great significance for improving the sustainable development of agricultural production.

14.
Int J Biol Macromol ; 231: 123334, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36682667

ABSTRACT

An advanced hydrophobic lignin-based polyurethane coated urea (HLPCU) was successfully developed by synergy of carbon black (CB) and polysiloxane. In this work, CB and polysiloxane were employed to modify the liquefied lignin-based polyurethane (LLPU) and improve it's the hydrophobicity. The effects of polysiloxane contents and coating rates on the nutrient release of HLPCU were thoroughly investigated. The lignin was degraded into polyol with a low molecular weight. FT-IR, XPS and EDX results confirmed that polysiloxane was grafted to the LLPU. The water contact angle (WCA) of the HLPUs (89.39°-98.68°) gradually increased as the polysiloxane content rose (5 %-15 %). However, when the polysiloxane content further increased to 20 %, the WCA of the HLPUs rapidly declined (90.82°). A proper amount of polysiloxane molecules could increase thermo-physical properties of LLPU. The almost no pores were observed on the section micrograph of the HLPCU obtained by synergy of CB and polysiloxane. Synergy between CB and polysiloxane could significantly improve hydrophobicity and then enhance N release longevity of HLPCU (polysiloxane content of 15 %, coating rates of 7 %) up to 44 days. Compared to traditional urea, HLPCU could improve total N use efficiency the cabbage. The HLPCU and HLPCU85 treatments (15 % weight loss with fertilization) reduced the greenhouse effect of N2O, CO2 and CH4 and finally reduced GWP, especially for HLPCU85 treatment. This work will supply an advanced approach and process technology for progress of HLPCU and sustainable agriculture.


Subject(s)
Greenhouse Gases , Greenhouse Gases/analysis , Siloxanes , Soot , Lignin , Urea/chemistry , Polyurethanes , Spectroscopy, Fourier Transform Infrared , Fertilizers , Methane , Nitrous Oxide/analysis , Agriculture/methods , Soil , Carbon Dioxide
15.
Environ Sci Technol ; 57(1): 561-569, 2023 01 10.
Article in English | MEDLINE | ID: mdl-36443945

ABSTRACT

Fluorene-9-bisphenol (BHPF), a bisphenol A (BPA) substitute, has been increasingly used as a material in syntheses of polymers that are widely used in road markings, artificial tracks, coating floors, building paints, etc., increasing the likelihood of BHPF contamination in the aquatic environment due to its release from the products. However, to date, it is unknown whether it may have actual impacts on fish in real environments. In this study, a 105-day exposure experiment of BHPF at various concentrations (0.01, 0.1, 1, and 10 µg/L) on Chinese medaka (Oryzias sinensis) was performed under laboratory conditions and found decreased fecundity, such as lower egg qualities and quantities, retarded oogenesis, and atretic follicles in the fish and deformed eyes and bodies in its F1 generation. Toxico-transcriptome analyses showed that estrogen-responsive genes were significantly suppressed by BHPF, indicating that antagonist properties of BHPF on estrogen receptors might be causes for the decreased fecundity. Field investigations (Beijing) demonstrated that BHPF was detectable in 60% surface waters, with a mean concentration of 10.49 ± 6.33 ng/L, by gas chromatography-mass spectrometry, and similar effects in wild Chinese medaka were also observed, some of which the parameters were found to be obviously correlated with the BHPF levels in corresponding waters.


Subject(s)
Oryzias , Water Pollutants, Chemical , Animals , Fluorenes/toxicity , Fluorenes/chemistry , Reproduction , Water Pollutants, Chemical/toxicity
16.
Environ Pollut ; 317: 120724, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-36427818

ABSTRACT

Ecological toxicity assessments of contaminants in aquatic environments are of great concern. However, a dilemma in ecological toxicity assessments often arises when linking the effects found in model animals in the laboratory and the phenomena observed in wild fishes in the field due to species differences. Chinese medaka (Oryzias sinensis), widely distributed in East Asia, is a satisfactory model animal to assess aquatic environment in China. Here, we domesticated this species and assembled its genome (814 Mb) using next-generation sequencing (NGS). A total of 21,922 high-confidence genes with 41,306 transcripts were obtained and annotated, and their expression patterns in tissues were determined by RNA-sequencing. Six mostly sensitive biomarker genes, including vtg1, vtg3, vtg6, zp3a.2, zp2l1, and zp2.3 to estrogen exposure were screened and validated in the fish exposed to concentrations of estrone (E1), 17ß-estradiol (E2), and estriol (E3) under laboratory condition. Field investigations were then performed to evaluating the gene expression of biomarkers in wild Chinese medaka and levels of E1, E2, and E3 in the fish habitats. It was found that in 40 sampling sites, the biomarker genes were obviously highly expressed in the wild fish from about half sites, and the detection frequencies of E1, E2, and E3, were 97.5%, 42.5%, and 45% with mean concentrations of 82.48, 43.17, 52.69 ng/L, respectively. Correlation analyses of the biomarker gene expressions in the fish with the estrogens levels which were converted to EEQs showed good correlation, indicating that the environmental estrogens and estrogenicity of the surface water might adversely affect wild fishes. Finally, histologic examination of gonads in male wild Chinese medaka was performed and found the presence of intersex in the fish. This study facilitated the uses of Chinese medaka as a model animal for ecotoxicological studies.


Subject(s)
Oryzias , Water Pollutants, Chemical , Animals , Male , Biomarkers/metabolism , Estrogens/analysis , Estrone/analysis , Oryzias/genetics , Oryzias/metabolism , Transcriptome , Water Pollutants, Chemical/analysis
17.
Int J Biol Macromol ; 221: 1130-1141, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-36113589

ABSTRACT

Novel lignin/paraffin/epoxy resin composite coated urea (LPECCU) was successfully prepared. Paraffin and epoxy resin (ER) were used to improve the slow-release properties of the lignin-based polyurethane (LPU) coated urea. The relationships among the N release characteristics, liquid-solid rate, -CNO/-OH molar rate and film formation rate in the coating material of LPECCU were investigated. The results showed that the water contact angle (WCA) of the LPU-paraffin increased with the rate of liquid-solid rate (73.61-88.19°) and -CNO/-OH molar rate (65.17-82.24°) increased. The average particle hardness of LPECCU decreased with the increased of liquid-solid rate (57.10-66.80 N) and the reduced of -CNO/-OH molar rate (48.11-63.00 N). The LPECCU emerged compact micro-structure, low sustained release and high compressive resistance by adding paraffin and ER. The coating material of LPECCU appeared excellent biodegradability in the soil. The optimal N cumulative release rate (72.49 %) of LPECCU was obtained (liquid-solid rate of 1.43, -CNO/-OH molar rate of 2, and the film formation rate of 6.66 %). The lettuce growth study was conducted to further evaluate the pot application of the LPECCU. In comparison to conventional urea, LPECCU could improve the total dry matter accumulation and N use efficiency of the lettuce.


Subject(s)
Nitrogen , Urea , Urea/chemistry , Nitrogen/chemistry , Lignin/chemistry , Fertilizers , Epoxy Resins , Lactuca , Paraffin , Composite Resins , Polyurethanes/chemistry
18.
Math Biosci Eng ; 19(10): 10618-10636, 2022 07 26.
Article in English | MEDLINE | ID: mdl-36032009

ABSTRACT

A stochastic SIRS epidemic model with vaccination is discussed. A new stochastic threshold $ R_0/ $ is determined. When the noise is very low ($ R_0/ < 1 $), the disease becomes extinct, and if $ R_0/ > 1 $, the disease persists. Furthermore, we show that the solution of the stochastic model oscillates around the endemic equilibrium point and the intensity of the fluctuation is proportional to the intensity of the white noise. Computer simulations are used to support our findings.


Subject(s)
Models, Biological , Systemic Inflammatory Response Syndrome , Computer Simulation , Humans , Incidence , Stochastic Processes , Vaccination
19.
Chem Sci ; 13(27): 8193-8202, 2022 Jul 13.
Article in English | MEDLINE | ID: mdl-35919436

ABSTRACT

The origin of the enormous catalytic power of enzymes has been extensively studied through experimental and computational approaches. Although precise mechanisms are still subject to much debate, enzymes are thought to catalyze reactions by stabilizing transition states (TSs) or destabilizing ground states (GSs). By exploring the catalysis of various types of enzyme-substrate noncovalent interactions, we found that catalysis by TS stabilization and the catalysis by GS destabilization share common features by reducing the free energy barriers (ΔG ‡s) of reactions, but are different in attaining the requirement for ΔG ‡ reduction. Irrespective of whether enzymes catalyze reactions by TS stabilization or GS destabilization, they reduce ΔG ‡s by enhancing the charge densities of catalytic atoms that experience a reduction in charge density between GSs and TSs. Notably, in TS stabilization, the charge density of catalytic atoms is enhanced prior to enzyme-substrate binding; whereas in GS destabilization, the charge density of catalytic atoms is enhanced during the enzyme-substrate binding. Results show that TS stabilization and GS destabilization are not contradictory to each other and are consistent in reducing the ΔG ‡s of reactions. The full mechanism of enzyme catalysis includes the mechanism of reducing ΔG ‡ and the mechanism of enhancing atomic charge densities. Our findings may help resolve the debate between TS stabilization and GS destabilization and assist our understanding of catalysis and the design of artificial enzymes.

20.
Comput Math Methods Med ; 2022: 1797258, 2022.
Article in English | MEDLINE | ID: mdl-36017144

ABSTRACT

In this paper, a class of fractional deterministic and stochastic susceptible-infected-removed- susceptible (SIRS) epidemic models with vaccination is proposed. For the fractional deterministic SIRS epidemic model, the existence of solution and the stability of equilibrium points are analyzed by using dynamic method. Then, the appropriate controls are established to effectively control the disease and eliminate it. On this basis, the fractional stochastic SIRS epidemic model with vaccination is further considered, and a numerical approximation method is proposed. The correctness of the conclusion is verified by numerical simulation.


Subject(s)
Epidemics , Models, Biological , Epidemics/prevention & control , Humans , Stochastic Processes , Systemic Inflammatory Response Syndrome , Vaccination/methods
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