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1.
Sci Rep ; 14(1): 9992, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693305

RESUMO

A two-dimensional unsteady seepage model for coal using a finite element program is developed, and the temporal variations of key factors such as water pressure and hydraulic gradient are analyzed in this paper. Additionally, the triaxial rock mechanical experiment and utilized pneumatic fracturing equipment on raw coal samples to investigate both hydraulic and pneumatic fracturing processes are conducted. Through these experiments, the relationship between pressure and crack formation and expansion are examined. The analysis reveals that the pore pressure gradient at the coal inlet reaches its peak during rapid surges in water pressure but diminishes over time. Conversely, the pore pressure gradient at the outlet side exhibits a gradual increase. Hydraulic fracturing is most likely to occur at the water inlet during sudden increases in water pressure. Besides, as the permeability of coal decreases, the duration for seepage stabilization prolongs due to the intensified pore pressure gradient resulting from sudden increases in water pressure. Moreover, an extended period of high hydraulic gradient further increases the risk of hydraulic fracturing. The experimental findings indicate that coal samples initially experience tensile failure influenced by water and air pressure. Subsequently, mode I cracks form under pressure, propagating along the fracture surface and becoming visible. The main types of failure observed in hydraulic and pneumatic fracturing are diametrical tensile failure, and the development of fractures can be categorized into three distinct stages, which contains the initial stage characterized by slight volume changes while water pressure increases, the expansion stage when pressure reaches the failure strength, and the crack closure stage marked by little or even decreasing volume changes during pressure unloading. The acoustic emission signal accurately corresponds to these three stages.

2.
Adv Appl Microbiol ; 122: 127-150, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37085192

RESUMO

As a semi-essential amino acid, l-arginine (l-Arg) plays an important role in food, health care, and medical treatment. At present, the main method of producing l-Arg is the use of microbial fermentation. Therefore, the selection and breeding of high-efficiency microbial strains is the top priority. To continuously improve the l-Arg production performance of the strains, a series of metabolic engineering strategies have been tried to transform the strains. The production of l-Arg by metabolically engineered Corynebacterium glutamicum (C. glutamicum) reached a relatively high level. Escherichia coli (E. coli), as a strain with great potential for l-Arg production, also has a large number of research strategies aimed at screening effective E. coli for producing l-Arg. E. coli also has a number of advantages over C. glutamicum in producing l-Arg. Therefore, it is of great significance to screen out excellent and stable E. coli to produce l-Arg. Here, based on recent research results, we review the metabolic pathways of l-Arg production in E. coli, the research progress of l-Arg production in E. coli, and various regulatory strategies implemented in E. coli.


Assuntos
Corynebacterium glutamicum , Proteínas de Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Engenharia Metabólica/métodos , Arginina/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Fermentação
3.
Food Chem ; 412: 135581, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36731239

RESUMO

Nelumbo nucifera Gaertn, commonly known as lotus, is a genus comprising perennial and rhizomatous aquatic plants, found throughout Asia and Australia. This review aimed to cover the biosynthesis of flavonoids, alkaloids, and lipids in plants and their types in different parts of lotus. This review also examined the physiological functions of bioactive compounds in lotus and the extracts from different organs of the lotus plant. The structures and identities of flavonoids, alkaloids, and lipids in different parts of lotus as well as their biosynthesis were illustrated and updated. In the traditional medicine systems and previous scientific studies, bioactive compounds and the extracts of lotus have been applied for treating inflammation, cancer, liver disease, Alzheimer's disease, etc. We suggest future studies to be focused on standardization of the extract of lotus, and their pharmacological mechanisms as drugs or functional foods. This review is important for the lotus-based food processing and application.


Assuntos
Alcaloides , Lotus , Nelumbo , Nelumbo/química , Alcaloides/química , Extratos Vegetais/química , Flavonoides , Lipídeos
4.
BMC Urol ; 21(1): 184, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-34952574

RESUMO

OBJECTIVE: CT-Urography combined with 3D printing technology, digital design, construction of individualized PCNL puncture guides, and preliminary analyze their efficacy, safety puncture positioning for PCNL. METHODS: Twenty-two patients with renal calculi were randomly selected at the affiliated Hospital of Xuzhou Medical University during 2017-2018. We randomly divided the patients into two groups: in 10 experimental groups, we used our 3D printing personalized percutaneous puncture guide access plate for PCNL, and in the control group, 12 patients with standard USG guide PCNL. The accuracy of puncture position, puncture time, and intraoperative blood loss was compared. RESULTS: In the experimental group, 10 patients with 3D printing personalized percutaneous puncture guide access plate. The puncture needle was accessed through the guide plate and verified by the color Doppler. The single puncture, needle position, and depth success rate were 100.00% (10/10). The angles were consistent with the preoperative design. In the control group, 12 patients via USG guided PCNL success rate was 75.00% (9/12). The puncture time and amount of hemorrhage was (7.78 ± 0.94) min and (49.31 ± 6.43) mL, and (9.04 ± 1.09) min and (60.08 ± 12.18) mL, respectively. The above data of the two groups were statistically significant (P < 0.05). CONCLUSION: 3D printing personalized percutaneous nephrolithotomy guide plate for PCNL can improve PCNL renal puncture channel positioning accuracy, shorten puncture time, reduce intraoperative blood loss, bleeding-related complications and provide a new method for PCNL renal puncture positioning, which is worthy of further clinical exploration.


Assuntos
Cálculos Renais/cirurgia , Rim/diagnóstico por imagem , Nefrolitotomia Percutânea/métodos , Impressão Tridimensional , Adulto , Feminino , Humanos , Rim/anatomia & histologia , Cálculos Renais/diagnóstico por imagem , Cálculos Renais/patologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Punções , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler em Cores , Urografia
5.
Front Psychiatry ; 12: 656198, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512408

RESUMO

Objective: Somatization symptoms are commonly comorbid with depression. Furthermore, people with depression and somatization have a negative memory bias. We investigated the differences in emotional memory among adolescent patients with depressive disorders, with and without functional somatization symptoms (FSS). Methods: We recruited 30 adolescents with depression and FSS, 38 adolescents with depression but without FSS, and 38 healthy participants. Emotional memory tasks were conducted to evaluate the emotional memory of the participants in the three groups. The clinical symptoms were evaluated using the Hamilton Depression Rating Scale (HDRS) and the Children's Somatization Inventory (CSI). Results: The valence ratings and recognition accuracy rates for positive and neutral images of adolescent patients were significantly lower than those of the control group (F = 12.208, P < 0.001; F = 6.801, P < 0.05; F = 14.536, P < 0.001; F = 6.306, P < 0.05, respectively); however, the recognition accuracy rate for negative images of adolescent patients of depression without FSS was significantly lower than that of patients with FSS and control group participants (F = 10.316, P < 0.001). These differences persisted after controlling for HDRS scores. The within-group analysis revealed that patients of depression with FSS showed significantly higher recognition accuracy rates for negative images than the other types (F = 5.446, P < 0.05). The recognition accuracy rate for negative images was positively correlated with CSI scores (r = 0.352, P < 0.05). Conclusion: Therefore, emotional memory impairment exists in adolescent patients of depression and FSS are associated with negative emotional memory retention.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33854561

RESUMO

OBJECTIVES: To evaluate the efficacy and safety of Ningmitai (NMT) capsules in patients with chronic epididymitis. METHODS: This prospective randomized controlled trial included 112 patients diagnosed with chronic epididymitis. The patients were randomized (1 : 1 : 1) to receive levofloxacin (LVX), NMT, or NMT combined with LVX for 4 weeks. The patients were followed up at 2 and 4 weeks after initiation of treatment and were evaluated in terms of Chronic Epididymitis Symptom Index (CESI) scores, epididymal nodules, and safety parameters. The primary endpoints were the CESI scores at the end of 2 and 4 weeks of treatment. The secondary endpoints included the mean epididymal nodule diameter and the clinical efficacy rate. Safety was evaluated by hepatorenal function tests and adverse event reports during the trial. RESULTS: After 2 weeks of treatment, the CESI score of the NMT group was significantly lower than that of the LVX group (P < 0.05). In addition, the clinical efficacy rate of the NMT group was significantly higher than that of the LVX group (55% vs. 8.33%, P < 0.0001), indicating that NMT has a rapid effect on chronic epididymitis. After 4 weeks of treatment, there was no significant difference in CESI scores or clinical efficacy rates between the two monotherapy regimens (P > 0.05); however, the mean diameter of epididymal nodules was significantly smaller in the NMT group than in the LVX group (P < 0.0001). Moreover, after 4 weeks of treatment, the patients in the LVX + NMT group, which had a clinical efficacy rate of 97.22%, had lower CESI scores (both P < 0.01) and a smaller epididymal nodule diameter (vs. LVX, P < 0.0001; vs. NMT, P < 0.05) than those in the other two groups. No adverse events or abnormal hepatorenal function were found during the study. CONCLUSION: NMT significantly improved CESI scores and epididymal nodule diameter in patients with chronic epididymitis. The combination of NMT and LVX provides a much better effect than monotherapy, and this treatment regimen was well tolerated.

7.
Sensors (Basel) ; 20(6)2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32210211

RESUMO

Due to the unsteady morphology of heterogeneous irises generated by a variety of different devices and environments, the traditional processing methods of statistical learning or cognitive learning for a single iris source are not effective. Traditional iris recognition divides the whole process into several statistically guided steps, which cannot solve the problem of correlation between various links. The existing iris data set size and situational classification constraints make it difficult to meet the requirements of learning methods under a single deep learning framework. Therefore, aiming at a one-to-one iris certification scenario, this paper proposes a heterogeneous iris one-to-one certification method with universal sensors based on quality fuzzy inference and a multi-feature entropy fusion lightweight neural network. The method is divided into an evaluation module and a certification module. The evaluation module can be used by different devices to design a quality fuzzy concept inference system and an iris quality knowledge concept construction mechanism, transform human logical cognition concepts into digital concepts, and select appropriate concepts to determine iris quality according to different iris quality requirements and get a recognizable iris. The certification module is a lightweight neural network based on statistical learning ideas and a multi-source feature fusion mechanism. The information entropy of the iris feature label was used to set the iris entropy feature category label and design certification module functions according to the category label to obtain the certification module result. As the requirements for the number and quality of irises changes, the category labels in the certification module function were dynamically adjusted using a feedback learning mechanism. This paper uses iris data collected from three different sensors in the JLU(Jilin University) iris library. The experimental results prove that for the lightweight multi-state irises, the abovementioned problems are ameliorated to a certain extent by this method.

8.
Eur J Ophthalmol ; 30(4): 658-667, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31014078

RESUMO

INTRODUCTION: Amblyopia is speculated to be an untreatable disease in the patient, who is beyond the critical period of vision; however, currently, it is treatable in adults. PURPOSE: This study aimed to elucidate whether the treatment is useful in both anisometropic amblyopia and strabismic amblyopia. In addition, the differences were detected between anisometropic amblyopia and strabismic amblyopia after the same perceptual treatment and whether the suppression in anisometropic amblyopia or strabismic amblyopia could be decreased before and after the treatment. METHODS: A binocular perceptual learning was applied for the treatment, the suppression was measured, and the patients were followed up for 2 months after training. Anisometropic amblyopia and strabismic amblyopia groups were subjected to the assessment of stereo, visual acuity, contrast sensitivity, and suppression before and after the training. RESULTS: After 6 weeks of "Diploma Gabor Orientation Coherence" training, in the anisometropic amblyopia group, the outcomes of visual acuity (t = 3.114, p = 0.026) and contrast sensitivity (t = 7.786, p = 0.001) were increased significantly. While in the strabismic amblyopia group, the outcomes of stereo (t = 2.987, p = 0.040) and contrast sensitivity (t = 3.638, p = 0.022) were increased significantly. CONCLUSION: After Diploma Gabor Orientation Coherence training in the same frequency and in the same duration, the anisometropic amblyopia group got an improvement in visual acuity, but the strabismic amblyopia group got an improvement in stereo. As there are evidences to show that anisometropic amblyopia and strabismic amblyopia were injured in different pathways, we think the diverse results might come from the different pathway injury in anisometropic amblyopia and strabismic amblyopia.


Assuntos
Ambliopia/terapia , Anisometropia/terapia , Aprendizagem por Discriminação/fisiologia , Estrabismo/terapia , Visão Binocular/fisiologia , Percepção Visual/fisiologia , Adulto , Ambliopia/fisiopatologia , Anisometropia/fisiopatologia , Sensibilidades de Contraste/fisiologia , Percepção de Profundidade/fisiologia , Feminino , Humanos , Masculino , Estrabismo/fisiopatologia , Acuidade Visual/fisiologia , Adulto Jovem
9.
Pak J Pharm Sci ; 32(3 Special): 1349-1353, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31551214

RESUMO

Qingnaopian has been used in traditional Chinese medicine for treating central nervous system (CNS) injury and inflammatory diseases. The aim of this study was to investigate the effects of Qingnaopian in concussion mice. C57BL/6 mice were used to establish the mild Traumatic Brain Injury (mTBI)/ concussion using the weight-drop techniques. Animal behavioral experiments righting reflex response and locomotor activity were assessed. The expression of pro inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), IL-1 and Glial fibrillary acidic protein (GFAP) were assessed by enzyme-linked immunosorbent assay (ELISA) and Western blot method, respectively. SPSS 19.0 software was used for statistical analysis. The results showed that righting reflex time and locomotor activity were higher in model group compared with those in control group. Qingnaopian treated mice had lower pro inflammatory cytokines, such as IL-1, IL-6 and TNF-α with alleviated GFAP. In short, Qingnaopian treatment improved GFAP induced by blow to head and inflammatory cytokines in concussion mice.


Assuntos
Concussão Encefálica/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Encefalite/tratamento farmacológico , Proteína Glial Fibrilar Ácida/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Concussão Encefálica/complicações , Ácidos Cumáricos/análise , Citocinas/líquido cefalorraquidiano , Medicamentos de Ervas Chinesas/química , Encefalite/líquido cefalorraquidiano , Encefalite/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Reflexo de Endireitamento/efeitos dos fármacos
10.
FEMS Microbiol Ecol ; 90(1): 290-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25065524

RESUMO

Ammonia-oxidising archaea (AOA) are increasingly recognised as the primary mediators of soil ammonia oxidation, particularly in acidic soils. To explore the niche segregation of AOA and ammonia-oxidising bacteria (AOB) and the potential effect of this segregation on nitrification rates and the nitrogen cycle in Chinese agricultural soils, AOA and AOB amoA gene databases were established, and 454 high-throughput sequencing was used to investigate the key factors leading to the niche segregation of these two types of microorganisms. qPCR results demonstrated that there were more functional genes for AOA than for AOB in most of the soils. AOA diversity was higher than AOB diversity in most of the soils with AOA operational taxonomic units (OTU) numbers ranging from 40 to 169 and AOB OTU numbers ranging from 18 to 105. pH was the most important factor influencing the community structure of AOA (P < 0.01) and AOB (P < 0.05), and acidophilic AOA (i.e. Nitrosotalea-related sequences) were dominant in soils with pH values below 6.0. In addition, AOA amoA gene copy numbers were significantly positively correlated with pH (P < 0.05), the ratio of AOA OTU numbers/AOB OTU numbers was significantly negatively correlated with pH (P < 0.05), and the percentage of sequences represented by the Nitrosotalea cluster was significantly negatively correlated with pH (P < 0.01).


Assuntos
Amônia/metabolismo , Archaea/classificação , Bactérias/classificação , Microbiologia do Solo , Agricultura , Archaea/genética , Archaea/isolamento & purificação , Archaea/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , China , Dados de Sequência Molecular , Nitrificação , Oxirredução , Solo/química
11.
Appl Microbiol Biotechnol ; 98(11): 5029-38, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24515728

RESUMO

Nitrite-dependent anaerobic methane oxidation (N-DAMO) is a recently discovered process linking the global carbon and nitrogen cycles. This process was reported to be mediated by "Candidatus Methylomirabilis oxyfera". To date, M. oxyfera-like bacteria have been detected in a limited number of freshwater habitats, but whether these bacteria occur in estuarine habitats is currently unknown. In this study, the distribution, diversity and abundance of M. oxyfera-like bacteria were studied in the sediment of the Jiaojiang Estuary of the East Sea (China). Both the 16S ribosomal RNA (rRNA) and pmoA genes confirmed the occurrence of M. oxyfera-like bacteria in the examined estuary. The recovered 16S rRNA gene sequences showed 91.5-97.2 % identity to the 16S rRNA gene of M. oxyfera, and the recovered pmoA gene sequences showed 85.1-95.4 % identity to the pmoA gene of M. oxyfera. Quantitative PCR further confirmed the occurrence of M. oxyfera-like bacteria in this estuary, with the abundance varying from 5.80 ± 0.28 × 10(4) to 8.35 ± 0.52 × 10(7) copies g (dry weight)(-1). Correlation analysis indicated that the sediment organic content was the most important factor affecting the distribution of M. oxyfera-like bacterial communities in the examined sediments among the environmental factors investigated. This study demonstrated for the first time the existence of M. oxyfera-like bacteria in an estuarine environment and showed the correlations between the distribution of these bacteria and the estuarine environmental conditions.


Assuntos
Bactérias/isolamento & purificação , Bactérias/metabolismo , Sedimentos Geológicos/microbiologia , Metano/metabolismo , Nitritos/metabolismo , Anaerobiose , Bactérias/classificação , Bactérias/genética , Proteínas de Bactérias/genética , China , Análise por Conglomerados , DNA Ribossômico/química , DNA Ribossômico/genética , Estuários , Dados de Sequência Molecular , Oxirredução , Filogenia , RNA Ribossômico 16S/genética , Água do Mar , Análise de Sequência de DNA
12.
PLoS One ; 7(8): e44122, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22952893

RESUMO

Ammonia oxidation is performed by both ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). To explore the effect of ammonia concentration on the population dynamic changes of ammonia-oxidizing microorganisms, we examined changes in the abundance and community composition of AOA and AOB in different layers. Most of the archaeal amoA sequences were Nitrosotalea-related and the proportion that Nitrosotalea cluster occupied decreased in the surface layer and increased in the deep layer during the cultivation process. Nitrosopumilus-related sequences were only detected in the deep layer in the first stage and disappeared later. Both phylogenetic and quantitative analysis showed that there were increased Nitrosomonas-related sequences appeared in the surface layer where the ammonia concentration was the highest. Both AOA and AOB OTU numbers in different layers decreased under selective pressure and then recovered. The potential nitrification rates were 25.06 µg · N · L(-1) · g(-1) dry soil · h(-1) in the mid layer which was higher than the other two layers. In general, obvious population dynamic changes were found for both AOA and AOB under the selective pressure of exogenous ammonia and the changes were different in three layers of the soil column.


Assuntos
Amônia/farmacologia , Archaea/crescimento & desenvolvimento , Bactérias/crescimento & desenvolvimento , Biota , Oryza/microbiologia , Microbiologia do Solo , Archaea/efeitos dos fármacos , Archaea/genética , Bactérias/efeitos dos fármacos , Bactérias/genética , Sequência de Bases , Dosagem de Genes/genética , Biblioteca Gênica , Genes Arqueais/genética , Genes Bacterianos/genética , Variação Genética/efeitos dos fármacos , Dados de Sequência Molecular , Nitrificação/genética , Oxirredução/efeitos dos fármacos , Filogenia , Reação em Cadeia da Polimerase em Tempo Real
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