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1.
Compr Rev Food Sci Food Saf ; 23(3): e13326, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38572572

RESUMO

A growing demand for sustainable, alternative protein sources that are nutrient-dense, such as microorganisms, and insects, has gradually evolved. When paired with effective processing techniques, yeast cells contain substantial substances that could supply the population's needs for food, medicine, and fuel. This review article explores the potential of yeast proteins as a sustainable and viable alternative to animal and plant-based protein sources. It highlights the various yeast protein extraction methods including both mechanical and non-mechanical methods. The application of nanoparticles is one example of the fast-evolving technology used to damage microbial cells. SiO2 or Al2O3 nanoparticles break yeast cell walls and disrupt membranes, releasing intracellular bioactive compounds. Succinylation of yeast protein during extraction can increase yeast protein extraction rate, lower RNA concentration, raise yeast protein solubility, increase amino acid content, and improve yeast protein emulsification and foaming capabilities. Combining physical and enzymatic extraction methods generates the most representative pool of mannose proteins from yeast cell walls. Ethanol or isoelectric precipitation purifies mannose proteins. Mannoproteins can be used as foamy replacement for animal-derived components like egg whites due to their emulsification, stability, and foaming capabilities. Yeast bioactive peptide was separated by ultrafiltration after enzymatic hydrolysis of yeast protein and has shown hypoglycemic, hypotensive, and oxidative action in vitro studies. Additionally, the review delves into the physicochemical properties and stability of yeast-derived peptides as well as their applications in the food industry. The article infers that yeast proteins are among the promising sources of sustainable protein, with a wide range of potential applications in the food industry.


Assuntos
Manose , Saccharomyces cerevisiae , Animais , Dióxido de Silício , Indústria Alimentícia , Proteínas Fúngicas , Proteínas de Plantas/química , Peptídeos
3.
Metab Eng ; 82: 29-40, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38224832

RESUMO

Yarrowia lipolytica is widely used in biotechnology to produce recombinant proteins, food ingredients and diverse natural products. However, unstable expression of plasmids, difficult and time-consuming integration of single and low-copy-number plasmids hampers the construction of efficient production pathways and application to industrial production. Here, by exploiting sequence diversity in the long terminal repeats (LTRs) of retrotransposons and ribosomal DNA (rDNA) sequences, a set of vectors and methods that can recycle multiple and high-copy-number plasmids was developed that can achieve stable integration of long-pathway genes in Y. lipolytica. By combining these sequences, amino acids and antibiotic tags with the Cre-LoxP system, a series of multi-copy site integration recyclable vectors were constructed and assessed using the green fluorescent protein (HrGFP) reporter system. Furthermore, by combining the consensus sequence with the vector backbone of a rapidly degrading selective marker and a weak promoter, multiple integrated high-copy-number vectors were obtained and high levels of stable HrGFP expression were achieved. To validate the universality of the tools, simple integration of essential biosynthesis modules was explored, and 7.3 g/L of L-ergothioneine and 8.3 g/L of (2S)-naringenin were achieved in a 5 L fermenter, the highest titres reported to date for Y. lipolytica. These novel multi-copy genome integration strategies provide convenient and effective tools for further metabolic engineering of Y. lipolytica.


Assuntos
Yarrowia , Yarrowia/genética , Yarrowia/metabolismo , Plasmídeos/genética , Engenharia Metabólica , Biotecnologia , Proteínas Recombinantes/genética
4.
ACS Appl Mater Interfaces ; 16(3): 4126-4137, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38191293

RESUMO

Droplet directional transport is one of the central topics in microfluidics and lab-on-a-chip applications. Selective transport of diverse droplets, particularly in another liquid phase environment with controlled directions, is still challenging. In this work, we propose an electric-field gradient-driven droplet directional transport platform facilitated by a robust lubricant surface. On the platform, we clearly demonstrated a liquid-inherent critical frequency-dominated selective transport of diverse droplets and a driving mechanism transition from electrowetting to liquid dielectrophoresis. Enlightened by the Kelvin-Helmholtz theory, we first realize the directional droplet transport in another liquid phase whenever a permittivity difference exists. Co-transport of multiple droplets and various combinations of droplet types, as well as multifunctional droplet transport modes, are realized based on the presented powerful electric-field gradient-driven platform, overcoming the limitations of the surrounding environment, liquid conductivity, and intrinsic solid-liquid wetting property existing in traditional droplet transport strategies. This work may inspire new applications in liquid separation, multiphase microfluidic manipulation, chemical reagent selection, and so on.

5.
Adv Mater ; 36(4): e2304364, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37885340

RESUMO

Self-assembling peptides are valuable building blocks to fabricate supramolecular biomaterials, which have broad applications from biomedicine to biotechnology. However, limited choices to induce different globular proteins into hydrogels hinder these designs. Here, an easy-to-implement and tunable self-assembling strategy, which employs Ure2 amyloidogenic peptide, are described to induce any target proteins to assemble into supramolecular hydrogels alone or in combination with notable compositional control. Furthermore, the collective effect of nanoscale interactions among amyloid nanofibrils and partially disordered elastomeric polypeptides are investigated. This led to many useful macroscopic material properties simultaneously emerging from one pure protein material, i.e. strong adhesion to any substrates under wet conditions, rapidly self--assembling into robust and porous hydrogels, adaptation to remodeling processes, strongly promoting cell adhesion, proliferation and differentiation. Moreover, he demonstrated this supramolecular material's robust performance in vitro and vivo for tissue engineering, cosmetic and hemostasis applications and exhibited superior performance compared to corresponding commercial counterparts. To the best of his knowledge, few pure protein-based materials could meet such seemingly mutually exclusive properties simultaneously. Such versatility renders this novel supramolecular nanomaterial as next-generation functional protein-based materials, and he demonstrated the sequence level modulation of structural order and disorder as an untapped principle to design new proteins.


Assuntos
Proteínas Amiloidogênicas , Proteínas de Insetos , Nanoestruturas , Peptídeos/química , Nanoestruturas/química , Amiloide/química , Materiais Biocompatíveis/química , Hidrogéis/química
6.
RSC Adv ; 13(45): 31659-31666, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37908647

RESUMO

Reversed-electrowetting based droplet electricity generator (REWOD-DEG) shows merits in high power densities, tunable output formats, and wide adaptability to diverse mechanical energies. However, the surface charge trapping and dielectric failure, which are also common challenges for electrowetting system, hinders the development of reliable REWOD-DEGs for long-term running. We innovatively introduce a slippery lubricant-infused porous surface (SLIPS) into REWOD-DEG. Benefits from the significant inhibitory effect for surface charge trapping and ambient contamination, self-healing characteristic given by SLIPS, and robust reversed-electrowetting based energy harvesting were achieved. The SLIPS enhanced REWOD-DEG experienced 100 days of intermittent energy harvesting without deterioration. In addition, the device shows robust performances when exposed to a variety of extreme working conditions, like low temperature, pH, humidity, fouling, and even scratching. This work may address the core application challenges of REWOD based devices, and inspire the development of other robust droplet-based electricity generators.

7.
BMC Cancer ; 23(1): 1113, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968600

RESUMO

BACKGROUND: Children with acute lymphoblastic leukaemia (ALL) experience multiple symptoms that occur in complicated patterns and negatively affect patient outcomes. To date, no systematic review has been performed on the prevalence of symptoms in children with ALL. OBJECTIVE: The study aimed to report and analyse the prevalence of symptoms in children with ALL during treatment. METHODS: A systematic search was conducted in eight databases (PubMed, Ovid Embase, Web of Science, CINAHL, PsycINFO, China WanFang Database, China Science and Technology Journal Database, and China National Knowledge Infrastructure) for studies published between January 1, 2000, and August 12, 2023. The methodological quality of the included studies was evaluated and a meta-analysis was performed to pool the prevalence of symptoms. RESULTS: In total, 17 studies were included, from which 34 symptoms were identified. The symptom prevalence ranged between 1.5 and 91.0% and the most frequent symptoms observed were fatigue, lack of energy, dry mouth, lack of appetite, sweating, and feeling irritable, which occurred in at least 60% of the patients. CONCLUSIONS: Symptoms remain highly prevalent in paediatric patients with ALL, which provides support for the need for symptom assessment in the clinical setting. Specific intervention is urgently needed to mitigate the symptoms in children with ALL and help them cope with the symptom burden.


Assuntos
Emoções , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Criança , Prevalência , China/epidemiologia , Fadiga/epidemiologia , Fadiga/etiologia , Fadiga/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia
8.
Sci Total Environ ; 904: 166738, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37659563

RESUMO

Grasslands represent the largest ecosystem in China, accurate and efficient extraction of its integrated vegetation cover (IVC) plays a crucial role in supporting policy decisions. This study presented a method for grassland monitoring via IVC derived from high-resolution satellite data. Taking the multispectral data of Gaofen-1 (GF-1) and Gaofen-6 (GF-6) with 16 m resolution as the main data source, vegetation cover of six representative regions was assessed based on mixed-pixel decomposition model. Using grassland vegetation cover and ratio of grassland area, the IVC in each site was calculated and verified against ground-measured sample data. The results showed that the IVC of grassland was closely related to vegetation habitat driven by regional hydrothermal regime. Yichang grassland, dominated with warm-temperate shrub tussock type, had the highest IVC (80.06 %) due to its favorable hydrothermal conditions. For the main grassland types in Hulunbuir and Gansu Province (temperate meadow steppe and temperate typical steppe), the IVC was 79.38 % and 58.46 %, respectively. In both Xilin-Gol and Nagqu, vegetation cover decreased gradually from east to west, and the IVC was merely 42.83 % and 42.61 %, respectively. Both regions are endowed with less hydrothermal resources to different degrees. Alxa, with a predominately temperate desert landscape, had the lowest IVC of 15.58 % where precipitation is extremely scarce. Based on the grass species of measured samples, the dominant species and biodiversity of different grassland types in Gansu Province and Hulunbuir Municipality of Inner Mongolia Autonomous Region were analyzed. The results showed that the meadow grassland has the richest biodiversity. The temperate mountain meadows in Gansu Province have a high species diversity, with a total of 90 grass species, and the lowland meadows in Hulunbuir have a total of 49 grass species. This study utilizes high-resolution data to conduct large-scale vegetation monitoring, which is a viable alternative for efficient assessment of steppe ecology.

9.
Sensors (Basel) ; 23(16)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37631695

RESUMO

The assessment of land cover and changes will help to understand the temporal and spatial pattern of land cover in the world and the Belt and Road (B&R) region, and provide reference information for global sustainable development and the Belt and Road construction. In this paper, the 1 km global land cover classification maps of 2016 and 2020 with a high accuracy of 88% are mapped using the Moderate Resolution Imaging Spectroradiometer (MODIS) time series surface reflectance products. Based on the maps, the land cover status of the world and the Belt and Road region, the land cover change from 2016 to 2020, and the mutual transformation characteristics between various types, are analyzed. The research results indicate that from 2016 to 2020, the global change rates of cropland, forest, grassland, and impervious surface are 0.25%, 0.22%, 0.08% and 3.41%, respectively. In the Belt and Road region, the change rates of cropland, forest, grassland, and impervious surface are 0.42%, 0.60%, -0.55% and 2.98% respectively. The assessment results will help to clarify the spatial pattern of land cover change in the five years from 2016 to 2020, so as to provide valuable scientific information for the global realization of sustainable development goals and the construction of the B&R.

10.
J Cancer Surviv ; 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37610477

RESUMO

PURPOSE: To investigate the level of fear of cancer recurrence (FCR) in spouses of patients with lymphoma and its relationship with patients' FCR, as well as the correlations between FCR, sense of spousal support (SSS), anxiety, and depression in the couples. METHODS: A cross-sectional study of 233 couples where one partner had lymphoma was conducted from May 2021 to February 2022. Participants provided demographic information and completed the Spouse Support Inventory and Hospital Anxiety and Depression Scale. The Fear of Progression Questionnaire (for patients) and Fear of Progression Questionnaire for Partners (for spouses) were used to measure FCR. Descriptive analyses, t-tests, variance analysis, Spearman's correlation analysis, and multiple linear regression analysis was performed. RESULTS: The prevalence of FCR, anxiety, and depression in patients was 37.7%, 68.7%, and 83.3%, respectively. The prevalence of FCR, anxiety, and depression in spouses was 56.2%, 78.1%, and 81.1%, respectively. Spouses' FCR scores were higher than those of patients, whereas patients' SSS and anxiety scores were higher than those of their spouses. Multiple linear regression analysis showed that patients' anxiety and SSS, as well as spouses' FCR were significantly associated with patients' FCR. Variables significantly associated with higher FCR among spouses were anxiety, per capita monthly household income, and patients' FCR. CONCLUSIONS: Patients with lymphoma and their spouses have a certain degree of FCR, anxiety, and depression. FCR levels in spouses are higher than in patients. IMPLICATIONS FOR CANCER SURVIVORS: Psychological support interventions for couples may be effective in reducing FCR and facilitating family adaptation to cancer.

11.
Waste Manag ; 171: 43-53, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37647725

RESUMO

The waste-to-energy and manganese industries face significant ecological challenges due to two major risk sources: municipal solid waste incineration (MSWI) fly ash and electrolytic manganese residue (EMR), especially, the MSWI fly is classified as hazardous waste. High temperature melting is a promising method for harmless disposal of solid wastes. However, it has yet to be industrialized due to the high costs and energy consumption. This study proposes using EMR as an additive to co-melt with MSWI fly ash, aiming to develop a method that minimizes energy consumption while producing high value-added products. To this end, the phase evolution and phase-change cooling characteristics during the co-melting process of MSWI fly ash and EMR were experimentally investigated. XRD and SEM analyses revealed that pure vitreous slag can be obtained when mixtures are heated to 1500 °C for 120 min with ≥40 wt% EMR addition under natural air-cooling conditions. Additionally, to produce vitreous slag by air-cooling and increase MSWI fly ash treatment capacity, the molten mixture with 30 wt% EMR addition was adopted in the directional solidification experiments to establish a predictive model relating the average cooling rate to the glass content. The findings ultimately contribute to the advancement of melting-based industrial applications.

12.
Medicine (Baltimore) ; 102(7): e32750, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36800584

RESUMO

BACKGROUND: Escherichia coli can cause severe infections. The latter can lead to disseminated intravascular coagulation (DIC). The importance of an early diagnosis of DIC is illustrated through this case report. AIM: Review the utility and shortcomings of representative clinical indicators of E coli infection and DIC. CASE REPORT: A 48-year-old man presented with diarrhea, nausea, and vomiting with fever of 2-day duration, during which consciousness was lost for 12 hour. Hematology was undertaken. The coagulation profile, liver function, and kidney function were determined, and blood cultures undertaken. The final diagnosis was acute gastroenteritis complicated by DIC. Meropenem (1.0 g, q8h, i.v.) was started, along with active replacement of fluids. Anticoagulant therapy (low-molecular-weight heparin 0.4 mL, q.d.s.) was given. Plasma supplementation of coagulation factors and albumin was applied. On day-5 of therapy, hematology showed the platelet count, D-dimer level, and prothrombin time to be improved significantly. Low-molecular-weight heparin treatment was stopped and antibiotic treatment was continued for 1 week. The patient made a full recovery. CONCLUSIONS: In severe infection, timely assessment of the platelet count, procalcitonin level, coagulation function, as well as rational use of antibiotics, can improve the prognosis of patients.


Assuntos
Coagulação Intravascular Disseminada , Masculino , Humanos , Pessoa de Meia-Idade , Coagulação Intravascular Disseminada/diagnóstico , Coagulação Intravascular Disseminada/etiologia , Escherichia coli , Anticoagulantes/uso terapêutico , Testes de Coagulação Sanguínea , Heparina de Baixo Peso Molecular
13.
Annu Rev Food Sci Technol ; 14: 225-246, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36696571

RESUMO

Lipids are a large group of essential nutrients in daily diets that provide energy and maintain various physiological functions. As the global population is rapidly expanding, there is an urgent need to enhance the production and quality of food lipids. The development of modern biotechnology allows the manipulation of oil production in plants and microorganisms and the improvement of the nutritional value of food lipids. Various metabolic engineering strategies have been exploited to increase oil production and produce value-added oils in traditional oil crops and other novel lipid sources (e.g., plant vegetative tissues, microalgae, and oleaginous microorganisms). Furthermore, natural lipid structures can be modified by lipases to prepare functional lipids, e.g., diacylglycerols, medium-long-medium-type structured triacylglycerols, human milk-fat substitutes, and structuralphospholipids, for specific nutritional demands. In this review, we focus on the recent advances in metabolic engineering of lipid production in plants and microorganisms, and the preparation of functional lipids via biocatalysis.


Assuntos
Biotecnologia , Óleos , Humanos , Triglicerídeos/química , Lipase/química , Lipase/metabolismo
14.
Eur J Oncol Nurs ; 62: 102262, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36603493

RESUMO

PURPOSE: This study aimed to explore the positive experiences of dyadic coping between patients with acute leukemia and their spouses in China, and to highlight the target factors that could promote coping and adaptation. METHODS: A qualitative descriptive study was employed. This study was conducted at a tertiary hospital in China from September 2021 to February 2022. A purposive sampling method was used to select participants, and 17 patients diagnosed with acute leukemia and their spouses were interviewed. Qualitative data were analyzed using the content analysis method. This study followed the COREQ checklist. RESULTS: This study's data were categorized into five themes and twelve subthemes: (1) adapting to a new role-couples used role adjustments to adapt; (2) commitment to companionship-patients benefit from spousal commitment in word or in deed; (3) active communication-allows couples to get to know each other better; (4) white lies-shield partner from negative information; (5) seeking external support-outside of couple cohesion. In sum, positive dyadic coping experiences between couples follow the marital commitment of "never forsake." CONCLUSIONS: This study contributes new knowledge to the understanding of the dyadic coping experiences of patients with acute leukemia and their spouses within the Chinese social-cultural context and contributes to cross-cultural comparisons. The results can be used to design and implement couple-based intervention programs to support couples by enhancing their mutual support to cope with and adjust to acute leukemia effectively.


Assuntos
Leucemia , Cônjuges , Humanos , Adaptação Psicológica , Relações Interpessoais , Estresse Psicológico , Leucemia/terapia
15.
Analyst ; 147(21): 4876-4887, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36155591

RESUMO

As the gold standard for nucleic acid detection, full-process polymerase chain reaction (PCR) analysis often falls into the dilemma of complex workflow, time-consuming, and high equipment costs. Therefore, we designed and optimized a DNA quantification microfluidic system by strategically integrating sample pretreatment and a smartphone-readable gradient plasmonic photothermal (GPPT) continuous-flow PCR (CF-PCR). Through preloading and sequential injection of immiscible extraction reagents, combined with magnetic bead (MB) manipulation, the microfluidic chip successfully purified and concentrated 100 µL of HBV-DNA spiked plasma into a 20-µL purified sample within 14 minutes. With a digital PCR platform, the optimized experiments showed that the DNA extraction efficiency can reach 69% at an immiscible reagent configuration ratio of 10 : 10 : 1 : 12 : 2 (sample : lysis/binding buffer : MB : silicone oil : eluent) and a flow rate of 25 µL min-1. For the first time, we used gold nanorod (AuNR)-doped PDMS to prepare a CF-PCR submodule for the amplification of a 40 µL PCR mixture. Due to the plasmonic photothermal effect of AuNRs and the gradient intensity of an expanded laser spot, the PCR thermal gradient was formed on a coin-sized area. The compact annular thermal-microfluidic layout, optimized DNA dye concentration, and chip transmittance synergistically enable a rarely reported smartphone-based fluorescence CF-PCR, greatly simplifying thermal control and detection setup. Prototype construction and validation experiments show that the microsystem can complete the sample-to-answer quantification of HBV-DNA with a dynamic linear range from 1.2 × 101 to 1.2 × 106 copies per µL in ∼37 minutes. This novel microfluidic solution effectively bridges the technical gap between the CF-PCR, sample pretreatment and result characterization, making the workflow standardized and rapid and requiring <15% of the commercial instrument cost. The simplicity, rapidity and low cost of this work make it promising for applications in decentralized laboratories and low-resource settings.


Assuntos
Técnicas Analíticas Microfluídicas , Microfluídica , DNA Viral/genética , Smartphone , Óleos de Silicone , Reação em Cadeia da Polimerase , Indicadores e Reagentes
16.
Cancer Biol Ther ; 23(1): 439-445, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-35921289

RESUMO

Exosome DNA (exoDNA) can be used for liquid biopsy. This study was the first to use droplet digital PCR (ddPCR) to detect tumor-specific mutations in exoDNA and to evaluate the prognosis of hepatocellular carcinoma (HCC) patients. 60 HCC patients were enrolled in the study. We used ddPCR to detect c.747 G > T mutation in TP53 gene. We analyzed the correlation between detectable mutation in exoDNA and clinicopathologic characteristics using Multivariate logistics regression analysis. We performed Cox regression to assess the correlation between mutation frequency (mutant droplets/total droplets, MD/TD) and prognostic. We found that 48 of 60 patients had c.747 G > T mutation in TP53 gene in exoDNA (80.0%). We found that detectable mutation in exoDNA and age were associated with microvascular invasion (MVI) (P < .01). The ROC curve analysis revealed that the best cutoff value of mutation frequency to predict MVI was 67% (sensitivity 48.15%, specificity 93.94%,), the corresponding AUC was 0.761 (95%CI, 0.640-0.866; P < .01). Furthermore, we found that patients suffered high-frequency mutation (>67%) had shorted median recurrence-free survival (RFS) with 63 days (range, 53-202 days), compared with 368 days (range, 51-576 days) for patients with low-frequency mutation (<67%) (HR:4.61; 95% CI, 1.70-12.48; P = 0 .003). We also found that high-frequency mutation was associated with poor prognosis though patients had better pathological characteristics, such as AFP (<400 ng/mL), Liver cirrhosis (Negative), Tumor thrombus (Negative), Tumor numbers (Single) and Post-operation TACE (Executed). We provided evidence that the mutations in exoDNA might be used to predict patients with poor RFS.Abbreviations: TP53: Tumor protein p53; ExoDNA: Exosomal DNA; HCC: Hepatocellular carcinoma; ddPCR: Droplet digital Polymerase Chain Reaction (PCR); MD/TD: The ratio of mutant droplets/total droplets; AFP: Alpha-fetoprotein; MVI: Microvascular invasion; RFS: Recurrence-free survival.


Assuntos
Carcinoma Hepatocelular , Ácidos Nucleicos Livres , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , Mutação , Prognóstico , Estudos Retrospectivos , Proteína Supressora de Tumor p53/genética , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo
17.
Sensors (Basel) ; 22(16)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36015709

RESUMO

We report a tomographic absorption spectroscopy (TAS) study of water vapor transport in a laminar jet issuing into the ambient. The jet was generated using compressed dry air that was straightened by a honeycomb and a smooth contraction nozzle. A TAS scheme using the water vapor in the ambient as absorbing species and the absorption line near 1368.598 nm was proposed to study the H2O transport in the laminar jet with an inverse concentration gradient. One-dimensional tomography was conducted at various heights above the nozzle, and the results were validated by the predictions from computational fluid dynamics (CFD) simulations. Particularly, the variations in the concentration gradient in the shear layer at different heights were captured. The 2D distribution of water concentration in the dry laminar jet was obtained experimentally. The present study shows that TAS has great potential in the research of mass transfer and scalar field of gaseous flows.


Assuntos
Vapor , Tomografia , Gases , Hidrodinâmica , Análise Espectral/métodos
18.
Biomaterials ; 287: 121650, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35872554

RESUMO

Cultured meat is meat for consumption produced in a more sustainable way. It involves cell harvesting and expansion, differentiation into myotubes, construction into muscle fibres and meat structuring. We isolated 5.3 × 104 porcine muscle stem cells from 1 g of neonatal pig muscle tissue. According to calculations, we need to expand muscle stem cells 106-107 times to produce 100 g or 1 kg of cultured meat. However, the cells gradually lost the ability to express stemness and mature muscle cell markers (PAX7, MyHC). To tackle this critical issue and maintain cell function during cell expansion, we found that long-term culture with (100 µM) l-Ascorbic acid 2-phosphate (Asc-2P) accelerated cell proliferation while preserving the muscle cell differentiation. We further optimized a scalable PDMS mold. Porcine muscle stem cells formed structurally-organized myotubes similar to muscle fibres in the mold. Asc-2P enhanced porcine muscle cells grown as 3D tissue networks that can produce a relatively large 3D tissue networks as cultured meat building blocks, which showed improved texture and amino acid content. These results established a realistic workflow for the production of cultured meat that mimics the pork meat structurally and is potentially scalable for industry.

19.
Sci Total Environ ; 844: 157111, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-35787896

RESUMO

Nitrogen (N) deposition has complex effects on vegetation dynamics and nutrient cycling in terrestrial ecosystems. However, how N deposition alters fine root traits remains unclear in forest ecosystems. Here, we carried out a synthesis based on 890 paired observations of 14 fine root traits from 79 articles to assess the effects of N deposition on fine root traits. The results showed that N deposition mainly affected root nutrient content and stoichiometry. Specifically, N deposition increased the root N content, root carbon: phosphorus (C:P) and root nitrogen: phosphorus (N:P) ratio, but decreased the root P content and root C:N ratio. Moreover, N deposition increased fine root respiration, but had no significant effect on other root morphological and physiological traits. N deposition effects on fine root biomass, root tissue density and fungal colonization decreased with N deposition duration. Compared to fine root P content, N deposition effects on fine root C content and C:P ratio increased with N deposition level. Moreover, the interaction between N deposition level and duration significantly affected fine root biomass. N deposition effects on fine-root biomass decreased with greater N deposition duration, especially in high N deposition experiments. Moreover, the effect of N deposition on root diameter decreased with mean annual temperature and mean annual precipitation. N form, forest type and soil depth significantly affect the effect of N deposition on fine root C:P. Therefore, the effects of N deposition on fine root traits were not only determined by N deposition level, duration and their interactions, but also regulated by abiotic factors. These findings highlight the diverse responses of fine root traits to N deposition have strong implications for forest ecosystems soil carbon stocks in a world of increasing N deposition associated with decreased root-derived carbon inputs and increases in fine-root respiration.


Assuntos
Ecossistema , Nitrogênio , Biomassa , Carbono , Florestas , Nitrogênio/análise , Fósforo , Raízes de Plantas/química , Solo
20.
Int J Biol Macromol ; 207: 927-940, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35364194

RESUMO

Up to now, unbalanced mechanical properties and poor heat resistance have become two major problems of polylactic acid (PLA). In this study, the coupling between Cellulose nanocrystal (CNC) and strong shearing field formed a unique hierarchical structure. Compared with pure PLA, the tensile strength of DPIM PLA/CNC increased from 57.9 MPa to 79.6 MPa without sacrificing the toughness of PLA, and the vicat softening temperature of DPIM PLA/CNC increased from 60 °C to 155 °C. The microstructure of PLA/CNC composites was analyzed by SEM, SAXS and WAXD, and it was found that the coupling effect of CNC and strong shear flow field could significantly change the crystallization behavior of PLA. CNC could increase PLA shish length from 251 nm to 889 nm under the action of shear field. At the same time, due to this coupling effect, more PLA shish-kebab structures were induced at the interface. This special hierarchical structure composed of CNC and PLA Shish-Kebab is of great significance and can provide important guidance for achieving the balance of strength and toughness of polymer materials.


Assuntos
Celulose , Nanopartículas , Celulose/química , Nanopartículas/química , Poliésteres/química , Espalhamento a Baixo Ângulo , Difração de Raios X
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