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BACKGROUND: The role of B cell subsets remained to be elucidated in a variety of immune diseases, though which was used as an effective biomarker for anti-inflammatory or antiviral response. This study aimed to evaluate the early changes of B cell subtypes distribution in elderly patients with community acquired pneumonia (CAP), as well as the association between B cell subtypes and prognosis. METHODS: This prospective study included elderly patients with CAP, severe CAP (sCAP) and healthy elderly subjects between April 2016 and March 2018. Flow cytometry was used to detect CD3, CD20, HLA-DR, CD24, CD27, CD38, IgM, and IgD. CD20+ B cells were further divided into naïve B cells (Bn), IgM/D+ memory B cells (IgM+ Bm), switched B cells (SwB), and transitional B cells (Btr). RESULTS: A total of 22 healthy controls, 87 patients with CAP and 58 patients with sCAP were included in the study. Compared to CAP, sCAP was characterized by significantly lower absolute number of B cells, Bn and Btr, significantly lower Btr and Bn subset percentage, while percentage of IgM+ Bm was significantly higher. Heat map showed Bn and Btr on day 3 and day 7 was negatively correlated with activated partial prothrombin time (APTT), international normalized ratio (INR), sequential organ failure assessment score (SOFA) and Acute Physiology and Chronic Health Evaluation II (APACHE II). After 28-day follow-up, Btr percentage in survival group was significantly higher. Receiver operator characteristic (ROC) curve analysis found that Btr count showed sensitivity of 48.6% and specificity of 87.0% for predicting the 28-day survival, with an area under the ROC curves of 0.689 (p = 0.019). CONCLUSIONS: Severity and prognosis of CAP in elderly people is accompanied by changes in the B cell subsets. Btr subsets could play prognostic role for a short-term mortality of elderly CAP patients.
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Subpopulações de Linfócitos B , Infecções Comunitárias Adquiridas , Pneumonia , Idoso , Humanos , Imunoglobulina M , Prognóstico , Estudos Prospectivos , Curva ROC , Estudos RetrospectivosRESUMO
BACKGROUND Anaplastic thyroid carcinoma (ATC) is a very rare, highly lethal malignant cancer. Our aim in this study was to develop nomograms that predict survival in ATC patients. MATERIAL AND METHODS ATC incidence and mortality were assessed via joinpoint regression analysis of 567 ATC patients selected from the Surveillance, Epidemiology, and End Results 18 Registries Research database. Predictive models were established via univariate and multivariate Cox regression analysis of potential risk factors and used to produce nomograms. Performance of the nomograms in terms of discrimination ability and calibration was evaluated by determining the concordance index (C-index) and by generating calibration plots, respectively. RESULTS The incidence and mortality rates for ATC increased from 2000 to 2015 according to the collected data (p<0.05). Two nomograms were constructed based on 2 predictive models: nomogram 1 considered age, tumor size, and metastasis (all before surgery), and nomogram 2 considered age, tumor size, metastasis, surgery, and extrathyroidal extension (all after surgery). Both nomogram 1 (C-index, 0.6803; 95% confidence interval, 0.6517-0.7089) and nomogram 2 (C-index, 0.7064; 95% confidence interval, 0.6783-0.7345) had good discrimination ability. The validated C-index values were 0.6783 and 0.7029 for nomogram 1 and 2, respectively. The observed values were in agreement with the calibration curves. CONCLUSIONS Nomogram 1 can assist in preoperative prediction of survival time in ATC patients, whereas nomogram 2 can provide additional outcome-related information.
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Previsões/métodos , Carcinoma Anaplásico da Tireoide/mortalidade , Adulto , Idoso , China , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Nomogramas , Valor Preditivo dos Testes , Prognóstico , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco , Neoplasias da Glândula Tireoide/mortalidadeRESUMO
We report the realization of a coherent perfect absorber, using a pair of passive resonators coupled to a microwave transmission line in the background, which can completely absorb light in its parity-time (PT-)symmetric phase but not in its broken phase. Instead of balancing material gain and loss, we exploit the incident waves in the open system as an effective gain so that ideal PT symmetry can be established by using only passive materials. Such a route will be effective to construct PT-symmetric metamaterials and also tunable PT-symmetric optical elements in general. It also provides a flexible platform for studying exceptional-point physics with both electric and magnetic responses.
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We report the first laser operation based on Ho(3+)-doped LuLiF(4) single crystal, which is directly pumped with 1.15-µm laser diode (LD). Based on the numerical model, it is found that the "two-for-one" effect induced by the cross-relaxation plays an important role for the laser efficiency. The maximum continuous wave (CW) output power of 1.4 W is produced with a beam propagation factor of M(2) ~2 at the lasing wavelength of 2.066 µm. The slope efficiency of 29% with respect to absorbed power is obtained.
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Lasers de Estado Sólido , Transferência de Energia , Desenho de Equipamento , Análise de Falha de EquipamentoRESUMO
OBJECTIVE: To explore the relationship between methylation status of XAF1 (X-linked inhibitor of apoptosis protein associated factor-1) gene promoter and its protein expression in papillary thyroid carcinoma (PTC). METHODS: Methylation-specific polymerase chain reaction (MSP) and immunohistochemical substance P (SP) technique were used to detect the methylation status of XAF1 gene promoter and its protein expression in 70 PTC cases and their matched adjacent non-cancerous epithelium (NCE). RESULTS: In NCE, there was no promoter methylation of XAF1 gene while the rate was 35.7% (25/70) in PTC (χ(2) = 27.206, P < 0.01). And it was correlated with tumor TNM stage, pathological grade and lymph node metastasis (P < 0.05). The positive rates of XAF1 protein expression in NCE and PTC were 100% (70/70) and 55.7% (39/70) respectively. And there was significant difference (χ(2) = 36.458, P < 0.01). In PTC, the positive rates of XAF1 protein expression in Grades I and II were 67.5% (27/40) and 40.0% (12/30) respectively. And they were 35.7% (10/28) and 69.0% (29/42) in the lymph node metastasis and non-metastasis groups respectively. And there were significant differences between two groups (P < 0.05). Futhermore, there was distinct correlation between methylation of XAF1 gene promoter and its protein expression (χ(2) = 8.864, P < 0.01). CONCLUSION: Methylation of promoter may be one of the important inactivating factors of XAF1 gene. And it plays an important role in the carcinogenesis and progression of PTC.
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Carcinoma/genética , Carcinoma/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Adolescente , Adulto , Idoso , Proteínas Reguladoras de Apoptose , Carcinoma/patologia , Carcinoma Papilar , Metilação de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/patologia , Adulto JovemRESUMO
On-chip light source is the main development part of the optoelectronic systems in the future. As on-chip light source, the main disadvantage of LED is its low extraction efficiency. Photonic crystal is an efficient method to increase the extraction efficiency of LED. The structure and parameters of the C-band LED was designed and the band gap of the 2D photonic crystals for different arrangement and different ratio was calculated using the finite-difference time-domain (FDTD) method, and then the best structural parameters of the 2D photonic crystals were determined using the method of band gap theory in this paper. Results show that the best structure is air holes PC with a triangular arrangement having a lattice constant of 500 nm and a ratio of 0.44.
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A system for demodulating distributed fiber Bragg grating sensors of the intelligent clothing was researched and realized, which is based on arrayed waveguide grating. The principle of demodulation method based on arrayed waveguide grating was analyzed, intensity--demodulating method was used to interrogate the wavelength of the fiber Bragg grating based on the building up of an experimental platform, and demodulation experiment of pre and post series of fiber Bragg grating was completed. The results show that the wavelength demodulation of the system has high linearity for fiber Bragg grating, the system gives a wavelength accuracy of 0.001 nm, and demodulation error caused by crosstalk between different sensors is 0.0005 nm. The measurement error of human body temperature is +/- 0.16 degrees C. It can be applied to the human body temperature measurement.
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Temperatura Corporal , Vestuário , Humanos , Fibras ÓpticasRESUMO
Understanding the nitrification capacity of coastal saline farmland soils and its main drivers is of great significance to regulate soil nitrification and improve the utilization efficiency of nitrogen fertilization in farmland. Using a combination of field investigations and laboratory analyses, we examined farmland soil nitrification potential and soil physical, chemical, and biological properties in the coastal muddy tidal flat saline soil area (Dongying and Dongtai). We established the correlation between soil properties and soil nitrification potential with multiple stepwise regression analyses and structural equation modeling (SEM). The results showed that soil pH value was relatively stable and other soil properties and soil nitrification potential varied in coastal saline farmland. The soil nitrification potential ranged from 0.04 to 10.42 mg·kg-1·d-1 and decreased with the increases of soil salinization level. Soil nitrification potential had the strongest correlation with soil organic matter, cation exchange capacity, and Cl-, with the correlation coefficient being 0.409, 0.397 and -0.337, respectively. The results of multiple stepwise regression analysis showed that Na+, silt, cation exchange capacity, and CO32-+HCO3- were the main influencing factors of soil nitrification potential. The results from the SEM analysis suggested that Na+, silt, cation exchange capacity, and CO32-+HCO3- directly affected soil nitrification potential, and soil organic matter, clay, Cl- and SO42- had indirect effects. In all, soil Na+ and cation exchange capacity were the two main factors affecting nitrification. Adjusting soil NaCl content and cation exchange capacity was an effective means of regulating soil nitrification.
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Nitrificação , Solo , Fazendas , Nitrogênio/análise , Solo/química , Microbiologia do SoloRESUMO
Biochar has been widely recognized as an effective and eco-friendly ameliorant for saline soils, but information about the mechanism of how biochar influences nitrification in salt-affected agroecosystem remains fragmented. An incubation experiment was performed on the salt-affected soil collected from a three-consecutive-year experiment at biochar application gradients of 7.5 tâ ha-1, 15 tâ ha-1 and 30â t ha-1 and under nitrogen (N) fertilization. Responses of the nitrification rate (NR), numbers of ammonia monooxygenase (amoA) gene copies, and community structures of ammonia-oxidizing bacteria (AOB) and archaea (AOA) to biochar application were investigated. The results indicated that, under N fertilization, the NR and numbers of amoA-AOB and amoA-AOA gene copies negatively responded to biochar addition. Biochar application increased the community diversity of AOB but decreased that of AOA. Biochar addition and N fertilization shifted the AOB community from Nitrosospira-dominated to Nitrosospira and Nitrosomonas-dominated, and altered the AOA community from Nitrososphaera-dominated to Nitrososphaera and Nitrosopumilus-dominated. The relative abundance of Nitrosospira, Nitrosomonas and Nitrosopumilus decreased, and that of Nitrosovibrio and Nitrososphaera increased with biochar application rate. Soil SOC, pH and NO3--N explained 87.1% of the variation in the AOB community, and 78.1% of the variation in the AOA community was explanatory by soil pH and SOC. The SOC and NO3--N influenced NR through Nitrosovibrio, Nitrosomonas, Norank_c_environmental_samples_p_Crenarchaeota and amoA-AOB and amoA-AOA gene abundance. Therefore, biochar addition inhibited nitrification in salt-affected irrigation-silting soil by shifting the community structures of AOB and AOA and reducing the relative abundance of dominant functional ammonia-oxidizers, such as Nitrosospira, Nitrosomonas and Nitrosopumilus.
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OBJECTIVE: To explore the mRNA and protein expressions of Runx3 gene in papillary thyroid carcinoma (PTC). METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot were used to detect the Runx3 mRNA and protein levels in 67 human PTC specimens and their matched adjacent non-cancerous epithelium (NCE). RESULTS: The relative expression value of Runx3 mRNA was 0.31 ± 0.07 in PTC versus 0.92 ± 0.08 in NCE (t = 38.251, P < 0.05). In PTC, it was correlated with the tumor pathological grade and lymph node metastasis (χ(2) = 5.511, 6.492, P < 0.05). The integral optical density value of Runx3 protein confirmed was 1012 ± 221 in PTC versus 1993 ± 199 in NCE (t = 18.413, P < 0.05). In PTC, it was correlated with the tumor TNM stage, pathological grade and lymph node metastasis (χ(2) = 5.550, 9.678, 5.070, P < 0.05). Furthermore there was a distinct correlation between the mRNA and protein expressions of Runx3 gene (χ(2) = 42.699, P < 0.05). CONCLUSION: The mRNA and protein expressions of Runx3 gene in PTC were lower than those in NCE. A lower expression of Runx3 gene may play an important role in the carcinogenesis and progression of PTC.
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Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Adolescente , Adulto , Idoso , Carcinoma , Carcinoma Papilar , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/genética , Adulto JovemRESUMO
Circular RNAs (circRNAs) have been shown to regulate the development and progression of various cancers. However, the expression and function of circRNAs in papillary thyroid cancer (PTC) remain largely unknown. This study is aimed to investigate the potential roles of circEIF3I in PTC and elucidate the functional mechanism. We found that the expression of circEIF3I was significantly upregulated in PTC tissues compared to adjacent normal tissues. CircEIF3I expression was positively associated with tumor size, TNM stage and metastasis. CircEIF3I knockdown remarkably suppressed the proliferation, migration and invasion of PTC cells. Mechanistically, circEIF3I promoted KIF2A expression through competitively interacting with miR-149. In conclusion, circEIF3I upregulation in PTC tissues facilitates KIF2A expression by inhibiting miR-149, leading to malignant progression of PTC. This study suggested circEIF3I/miR-149/KIF2A axis might be a potential therapeutic target.
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Based upon the review of the status of nitrogen use efficiency in salinized farmland in China, we summarized the effect of salinization on key processes of nitrogen transformation in farmland soil, analyzed the microbial mechanism underlying nitrogen transformation, and summed up the main ways for high efficient utilization of nitrogen in salinized farmland. Salinization had thre-shold effects on mineralization, nitrification, and denitrification of nitrogen from farmland soil, with the influence varying greatly in different scopes. Salinity and secondary barriers had different effects on microorganisms, with threshold in their effects. The most widely used methods for nitrogen synergism regulation in salinized farmland include soil conditioner, biomass material, growing salt-tole-rant plants, optimizing the ratio of different nitrogen forms, and biological inhibitor. We proposed current research shortcomings and future research directions of nitrogen cycle processes in salinized farmland. This study was of great significance for reducing nitrogen loss, enhancing utilization of nutrient from fertilizers, and controlling agricultural non-point source pollution in salinized farmland.
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Nitrogênio , Solo , China , Fazendas , Nitrogênio/análise , Ciclo do NitrogênioRESUMO
OBJECTIVE: To investigate the diet and nutritional status of hospitalized children with blood disease in order to provide nutritional guidelines. METHODS: The patients' daily dietary intakes, including breakfast, lunch, dinner and additional meals, were recorded in detail for seven consecutive days. The intake amount of various nutrients was calculated using the dietary database. RESULTS: The majority of children with blood disease showed inadequate intakes of calories [mean 1825.81 kCal/d, 73.62% of the recommended intake (RNI)] and protein (mean 67.68 g/d, 81.34% of RNI). Intakes of vitamin E and riboflavin were adequate, but intakes of vitamin A, thiamine and vitamin C (66.67%, 77.78% and 69.89% of RNI, respectively) were inadequate. Iron and selenium intakes were adequate, but calcium and zinc intakes (41.11% and 56.21% of RNI, respectively) were grossly inadequate. CONCLUSIONS: Hospitalized children with blood disease had decreased dietary intakes of calories, protein, vitamin A, vitamin C, thiamin, calcium and zinc. The dietary pattern and nutritional intake need to be improved.
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Ingestão de Energia , Doenças Hematológicas/metabolismo , Estado Nutricional , Adolescente , Ácido Ascórbico/administração & dosagem , Criança , Pré-Escolar , Feminino , Hospitalização , Humanos , Lactente , Masculino , Espécies Reativas de Oxigênio/metabolismo , Selênio/administração & dosagem , Vitamina A/administração & dosagem , Zinco/administração & dosagemRESUMO
As the most representative functional sugar, the application areas and market demands of xylo-oligosaccharides (XOS) have been expanding year by year. Owing to the complex structure of corn stalk (CS), XOS obtained from CS are accompanied by problems such as low purity and high color value, which degrade the product. To improve the quality of XOS from CS, the enzymatic hydrolysis was precipitated by acid; then, the ethanol elution concentration was systematically investigated after optimizing the adsorption conditions. The results showed that the purity of XOS was increased to 87.28% from 67.31%, and the color value was decreased to 1050 from 4682 when the acid precipitation pH was 2. On the basis of acid precipitation, if the corresponding optimal conditions of XOS adsorption and elution were used, the highest purity of XOS was 97.87% obtained, with the lowest color value, 780, which reached the standard of the commercial XOS.
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Oligossacarídeos , Etanol , Glucuronatos , Hidrólise , Zea maysRESUMO
As the second abundant natural carbohydrate, xylan is normally prepared through alkaline extraction and then used for xylo-oligosaccharides (XOS) production. However, the extracted xylan inevitably contains salt, ethanol, and pigment. In order to investigate the effects of these impurities on XOS production, the alkaline-extracted xylan with different kinds and concentrations of impurities was made and then hydrolyzed using alkaline xylanase (EC 3.2.1.8) to produce XOS. The results showed that a certain concentration of salt (NaCl) promoted the XOS production, while ethanol and pigment inhibited the enzymatic hydrolysis process significantly. The color value mainly ascribed to the phenolic compounds binding to xylan was a key restriction factor in the enzymatic hydrolysis later stage. Using optimal xylan sample (with 10 mg/mL NaCl, color value of 4.6 × 10(5), without ethanol) as substrate, the highest XOS yield of 58.58 % was obtained. As the substrate of XOS production, prepared xylan should contain colored materials and ethanol as less as possible, however, retains appropriate salt.
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Endo-1,4-beta-Xilanases/química , Oligossacarídeos/biossíntese , Pigmentos Biológicos/química , Xilanos/isolamento & purificação , Etanol/química , Hidrólise , Oligossacarídeos/química , Cloreto de Sódio/química , Temperatura , Xilanos/química , Xilose/química , Zea mays/químicaRESUMO
As the important structural component of corn stover, hemicellulose could be converted into a variety of high value-added products. However, high quality hemicellulose extraction is not an easy issue. The present study aims to investigate the effects of non-structural components (NSCs) and lignin removal on alkaline extraction of hemicellulose. Although NSCs were found to have a minimal effect on hemicellulose dissolution, they affected the color values of the hemicellulose extracts. The lignin limited the hemicellulose dissolution and increased the color value by binding to hemicellulose molecules and forming lignin-carbohydrate complexes. Sodium chlorite method can remove about 90% lignin from corn stover, especially the lignin connected to hemicellulose through p-coumaric and ferulic acids. Which increased the hemicellulose dissolution ratio to 93% and reduced the color value 14-28%, but the cost is about 20% carbohydrates lost.
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Carboidratos/química , Lignina/química , Polissacarídeos/química , Zea mays/química , Biotecnologia , Celulose/química , Cloretos/química , Etanol/química , TemperaturaRESUMO
BACKGROUND: Adult chronic idiopathic thrombocytopenic purpura (ITP) is a common hematologic disease characterized by persistent thrombocytopenia. So far, there were only a few reports on adult Chinese patients with chronic ITP. This study aimed at defining the treatment outcome and prognostic factors for chronic ITP based on a large cohort of Chinese patients followed up for over 25 years at a single center. METHODS: The medical records of 1791 patients aged 14 years or older who were diagnosed as having chronic ITP at our hospital from 1974 to 1999 were retrospectively analyzed. RESULTS: The female-to-male ratio was 2:1, with a median age of 34 years (ranging from 14 to 80 years), median platelet count of 38 x 10(9)/L [range (1-99) x 10(9)/L], and median follow-up of 36 months (range 1-220 months). Steroids were used in 689 patients, among them 209 (30.3%) achieved complete remission (CR). A splenectomy was performed in 124 patients, and response to steroid pre-splenectomy was not available in 14 patients. The CR rate after a splenectomy was lower in steroid nonresponders (29 of 90, 32.2%) than in those who relapsed after successful steroid treatment (12 of 20, 60.0%) (P < 0.05). In comparison with patients negative for antinuclear antibody (ANA), those who were ANA positive had similar responses to steroids, but a significantly shorter remission period after a splenectomy (P < 0.01). CONCLUSIONS: Adult Chinese chronic ITP patients can have long-term remission after steroid therapy and splenectomies. Primary steroid refractoriness is a prognostic factor predicting poor subsequent response to a splenectomy.
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Púrpura Trombocitopênica Idiopática/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antinucleares/sangue , Plaquetas/imunologia , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prednisolona/uso terapêutico , Prognóstico , Púrpura Trombocitopênica Idiopática/imunologia , Estudos Retrospectivos , Esplenectomia , Resultado do TratamentoRESUMO
A challenge for lignocellulosic pretreatment is how to retain hemicellulose as much as possible. To reduce the degradation of hemicellulose and increase the recovery of sugars, an effective pH pre-corrected liquid hot water pretreatment (LHWP) was developed by employing a small amount of NaOH (⩽5/100g substrate) to accelerate the hemicellulose deacetylation and simultaneously pre-correct the acid hydrolyzate in situ. The results showed that the pH pre-correction can control the hydrolyzate pH. Under the pretreatment severity (PS) of 4.0, the pH pre-corrected LHWP reduced the hemicellulose degradation by 35.3-92.3%, decreased furfural formation by 90.5-99.8%. The highest hemicellulose recovery of 96.38% was obtained with pH pre-corrected by 2g NaOH/100g substrate. Enzymatic hydrolysis (EH) and simultaneous saccharification and fermentation (SSF) on the whole slurry from the pH pre-corrected LHWP showed that the hemicellulose retained in the solid residue did not bring significant resistance to cellulose EH (p=0.837).
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Temperatura Alta , Polissacarídeos/isolamento & purificação , Resíduos , Água/farmacologia , Zea mays/química , Metabolismo dos Carboidratos/efeitos dos fármacos , Celulase/metabolismo , Fermentação/efeitos dos fármacos , Furaldeído/análise , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Hidrólise/efeitos dos fármacos , Lignina/análise , Fenóis/análise , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Zea mays/efeitos dos fármacos , Zea mays/ultraestruturaRESUMO
The mass distribution regularity in substrate of solid-state fermentation (SSF) has rarely been reported due to the heterogeneity of solid medium and the lack of suitable instrument and method, which limited the comprehensive analysis and enhancement of the SSF performance. In this work, the distributions of water, biomass, and fermentation product in different medium depths of SSF were determined using near-infrared spectroscopy (NIRS) and the developed models. Based on the mass distribution regularity, the effects of gas double-dynamic on heat transfer, microbial growth and metabolism, and product distribution gradient were systematically investigated. Results indicated that the maximum temperature of substrate and the maximum carbon dioxide evolution rate (CER) were 39.5°C and 2.48mg/(hg) under static aeration solid-state fermentation (SASSF) and 33.9°C and 5.38mg/(hg) under gas double-dynamic solid-state fermentation (GDSSF), respectively, with the environmental temperature for fermentation of 30±1°C. The fermentation production (cellulase activity) ratios of the upper, middle, and lower levels were 1:0.90:0.78 at seventh day under SASSF and 1:0.95:0.89 at fifth day under GDSSF. Therefore, combined with NIRS analysis, gas double-dynamic could effectively strengthen the solid-state fermentation performance due to the enhancement of heat transfer, the stimulation of microbial metabolism and the increase of the homogeneity of fermentation products.
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Reatores Biológicos , Celulase/metabolismo , Fermentação , Microbiologia Industrial/métodos , Proteínas de Plantas/metabolismo , Trichoderma/enzimologia , Movimentos do Ar , Biomassa , Dióxido de Carbono/metabolismo , Desenho de Equipamento , Temperatura Alta , Microbiologia Industrial/instrumentação , Microscopia Eletrônica de Varredura , Micélio/crescimento & desenvolvimento , Micélio/ultraestrutura , Caules de Planta , Espectroscopia de Luz Próxima ao Infravermelho , Trichoderma/crescimento & desenvolvimento , Trichoderma/ultraestrutura , Triticum , ÁguaRESUMO
The accurate determination on the key components in lignocellulosic biomass is the premise of pretreatment and bioconversion. Currently, the widely used 72% H2SO4 two-step hydrolysis quantitative saccharification (QS) procedure uses loss coefficient of monosaccharide standards to correct monosaccharide loss in the secondary hydrolysis (SH) of QS and may result in excessive correction. By studying the quantitative relationships of glucose and xylose losses during special hydrolysis conditions and the HMF and furfural productions, a simple correction on the monosaccharide loss from both PH and SH was established by using HMF and furfural as the calibrators. This method was used to the component determination on corn stover, Miscanthus and cotton stalk (raw materials and pretreated) and compared to the NREL method. It has been proved that this method can avoid excessive correction on the samples with high-carbohydrate contents.