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1.
RSC Adv ; 14(3): 1741-1749, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38192307

RESUMO

The main limit for the calcium looping process is the sharp decrease of the capture capacity of the CO2 sorbents during multiple cycles. In this research, a solution combustion method was employed to synthesize MgO-stabilized CaO sorbents. Polyethylene glycol (PEG) was used as the fuel and dispersant, with the purpose to enhance the uniformity of the Ca and Mg distributions in the sorbent. The results show that highly reactive MgO-stabilized CaO sorbents can be obtained through a solution combustion method using PEG as the fuel and dispersant. The existence of MgO can effectively restrain the sintering of the sorbent, resulting in a more porous and stable micro-structure of the sorbent. The CO2 capture capacity of the MgO-stabilized CaO sorbent synthesized under the optimum conditions is 0.40 g(CO2)/g(sorbent) after 20 cycles, which is 75.3% higher than CaCO3.

2.
Med Phys ; 51(2): 1034-1046, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38103259

RESUMO

BACKGROUND: Computed tomography (CT)-based positron emission tomography (PET) attenuation correction (AC) is a commonly used method in PET AC. However, the CT truncation caused by the subject's limbs outside the CT field-of-view (FOV) leads to errors in PET AC. PURPOSE: In order to enhance the quantitative accuracy of PET imaging in the all-digital DigitMI 930 PET/CT system, we assessed the impact of FOV truncation on its image quality and investigated the effectiveness of geometric shape-based FOV extension algorithms in this system. METHODS: We implemented two geometric shape-based FOV extension algorithms. By setting the data from different numbers of detector channels on either side of the sinogram to zero, we simulated various levels of truncation. Specific regions of interest (ROI) were selected, and the mean values of these ROIs were calculated to visually compare the differences between truncated CT, CT extended using the FOV extension algorithms, and the original CT. Furthermore, we conducted statistical analyses on the mean and standard deviation of residual maps between truncated/extended CT and the original CT at different levels of truncation. Subsequently, similar data processing was applied to PET images corrected using original CT and those corrected using simulated truncated and extended CT images. This allowed us to evaluate the influence of FOV truncation on the images produced by the DigitMI 930 PET/CT system and assess the effectiveness of the FOV extension algorithms. RESULTS: Truncation caused bright artifacts at the CT FOV edge and a slight increase in pixel values within the FOV. When using truncated CT data for PET AC, the PET activity outside the CT FOV decreased, while the extension algorithm effectively reduced these effects. Patient data showed that the activity within the CT FOV decreased by 60% in the truncated image compared to the base image, but this number could be reduced to at least 17.3% after extension. CONCLUSION: The two geometric shape-based algorithms effectively eliminate CT truncation artifacts and restore the true distribution of CT shape and PET emission data outside the FOV in the all-digital DigitMI 930 PET/CT system. These two algorithms can be used as basic solutions for CT FOV extension in all-digital PET/CT systems.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Tomografia por Emissão de Pósitrons/métodos , Imagens de Fantasmas , Artefatos , Processamento de Imagem Assistida por Computador/métodos
3.
BMC Microbiol ; 23(1): 389, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38057705

RESUMO

BACKGROUND: Depression and anxiety are common comorbid diseases of constipation. Fecal microbiota transplantation (FMT) significantly relieves gastrointestinal-related symptoms, but its impact on psychiatric symptoms remains uncharted. METHODS: We collected fecal and serum samples before and after FMT from 4 functional constipation patients with psychiatric symptoms and corresponding donor stool samples. We categorized the samples into two groups: before FMT (Fb) and after FMT (Fa). Parameters associated with constipation, depression, and anxiety symptoms were evaluated. Metagenomics and targeted neurotransmitter metabolomics were performed to investigate the gut microbiota and metabolites. 5-hydroxytryptamine (5-HT) biosynthesis was detected in patients' fecal supernatants exposed to the QGP-1 cell model in vitro. RESULTS: Our study demonstrated that patient's constipation, depression, and anxiety were improved after FMT intervention. At the genus level, relative abundance of g_Bacteroides and g_Klebsiella decreased in the Fa group, while g_Lactobacillus, and g_Selenomonas content increased in the same group. These observations suggest a potential involvement of these genera in the pathogenesis of constipation with psychiatric symptoms. Metabolomics analysis showed that FMT intervention decreased serum 5-HT levels. Additionally, we found that species, including s_Klebsiella sp. 1_1_55, s_Odoribacter splanchnicus, and s_Ruminococcus gnavus CAG:126, were positively correlated with 5-HT levels. In contrast, s_Acetobacterium bakii, s_Enterococcus hermanniensis, s_Prevotella falsenii, s_Propionispira arboris, s_Schwartzia succinivorans, s_Selenomonas artemidis, and s_Selenomonas sp. FC4001 were negatively correlated with 5-HT levels. Furthermore, we observed that patients' fecal supernatants increased 5-HT biosynthesis in QGP-1 cells. CONCLUSION: FMT can relieve patients' constipation, depression, and anxiety symptoms by reshaping gut microbiota. The 5-HT level was associated with an altered abundance of specific bacteria or metabolites. This study provides specific evidence for FMT intervention in constipation patients with psychiatric symptoms.


Assuntos
Transplante de Microbiota Fecal , Gastroenteropatias , Humanos , Depressão/terapia , Multiômica , Serotonina , Constipação Intestinal/terapia , Fezes/microbiologia , Ansiedade/terapia
4.
Macromol Rapid Commun ; 44(5): e2200795, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36482873

RESUMO

Stretchable electrodes are highly demanded in various wearable and flexible electronic devices, whereas the efficient fabrication approach is still a challenge. In this work, an efficient shrinking method to fabricate carbon nanotube (CNT)-based stretchable electrodes is proposed. The electrode is a layer of anisotropic CNT wrinkling film coated on a latex balloon substrate (CNT@latex), whose resistivity remains stable after 25 000 stretching cycles of 0 to 50% tensile strain, and can survive up to 500% tensile train. The highly conductive electrode can be used as the current collector of a stretchable Zinc-ion battery, maintaining an output voltage of 1.3 V during the stretching process of 0 to 100%. The applications of the electrode in flexible triboelectric nanogenerators and Joule heating devices are also demonstrated, further indicating their good prospects in the field of stretchable electronic devices.


Assuntos
Nanotubos de Carbono , Dispositivos Eletrônicos Vestíveis , Látex , Eletrodos , Eletrônica
5.
Front Microbiol ; 13: 1018008, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36246281

RESUMO

Functional constipation is a common functional gastrointestinal disease. In our previous study, we found that the gut microbiota structure was disordered and the level of phenylalanine (Phe) in serum was decreased in constipated women. We conducted the present study to elucidate the role of Phe in remodeling the composition of gut microbiota and the relationship between gut microbiota and serum metabolites. Here, we demonstrated that Phe treatment significantly enhanced intestinal motility, suppressed inflammatory responses, and prevented intestinal barrier damage in rats with loperamide (Lop)-induced constipation. By metagenomic sequencing, the disbalanced gut microbial profile was analyzed in constipated rats. Phe treatment reversed changes in the abundance of several gut bacteria at the phylum, genus, and species levels. Further, we observed distinct metabolic patterns in constipated rats through targeted metabolomics and identified constipation-related gut microbial species linked to changes in circulating neurotransmitter metabolites. The abundances of species s_Lactobacillus murinus, s_Enterococcus italicus, s_Lactobacillus animalis, s_Lactobacillus apodemi, s_Enterococcus faecalis, and s_Lactobacillus backii were positively correlated with L-asparagine, L-Glutamic acid, Putrescine, and Spermidine levels. The abundances of s_Lactobacillus johnsonii and s_Butyricimonas virosa were negatively correlated with L-asparagine, L-Glutamic acid, Putrescine, and Spermidine levels. Taken together, our findings suggest that Phe can ameliorate the development of Lop-induced constipation in rats by remodeling the gut microbial community structure and changing metabolite levels.

6.
Front Psychol ; 13: 918238, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35756320

RESUMO

Despite a wealth of research on the interaction behavior patterns among team members from different angles, few studies focus on the combination of innovation management and innovation team. With the "Input-Process-Output" theoretical framework, this study takes the coding analysis to explore the differences in the interaction behavior patterns of members caused by the cognitive differences in the higher and lower innovative-performing teams. An innovation experiment was conducted in 12 innovation teams based on an experimental paradigm proposed for team innovation tasks. Subsequently, team members' 1,754 behaviors were coded to analyze the similarities and differences in the interaction behavior patterns between higher and lower innovative-performing teams with lag sequential analysis. The results revealed that both higher and lower innovative-performing teams showed some same interaction behavior patterns. More specifically, the probability of idea facilitation behaviors being followed by team spirit facilitation behaviors was significantly higher than expected, while the probability of idea facilitation behaviors recurring was significantly lower than expected. However, in lower innovative-performing teams, there were some special interaction behavior patterns, such as "the probability of idea facilitation behaviors being followed by neutral interaction or idea inhibition behaviors was significantly lower than expected." These phenomena may reflect some realistic situations in our life, such as "One echoes the other," "Sitting on the sidelines" and "A gentleman is ready to die for his bosom friends" in the members' interaction after cognitive differences happen. This paper provides opinions and suggestions for the research on the interaction behavior observation and coding analysis among members of innovation teams, as well as theoretical contributions to the research on the behavior observation of innovation teams.

7.
Med Sci Monit ; 28: e934117, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35236817

RESUMO

BACKGROUND Chronic constipation is a common gastrointestinal disease. Our previous studies confirmed that there are differences in the composition and function of gut microbiota between women of reproductive age with chronic constipation and healthy controls. However, little is known about the differences in the metabolic profile of the 2 groups. The aim of this study was to observe changes in serum metabolites and identify potential metabolic pathways in the development of chronic constipation. MATERIAL AND METHODS A total of 50 participants were included in this study: 25 female patients of childbearing age with chronic constipation who met the inclusion and exclusion criteria and 25 healthy participants as a control group. Serum samples of these participants were collected; 1 portion of the serum sample was used for clinical biochemical analysis, and the other was used for non-targeted metabolomic testing. RESULTS Compared with the control group, serum 2-hydroxyphenylacetic acid levels were higher (P<0.05) and DL-phenylalanine levels were lower (P<0.05) in the constipation group. Other amino acids, such as 5-hydroxy-l-lysine and l-pipecolic acid, were upregulated, and L-valine, glycine, L-leucyl-L-proline, and N-formylmethionine were downregulated in the constipation group. In addition, levels of the bile acid, 3b-hydroxy-5-cholenoic acid, were higher in the constipation group than in the control group. Pathway analysis showed that the significantly altered pathways were phenylalanine metabolism and glycine, serine, and threonine metabolism. CONCLUSIONS These results strongly suggest that serum metabolites and pathways are significantly altered in women of reproductive age with chronic constipation.


Assuntos
Constipação Intestinal/sangue , Microbioma Gastrointestinal , Metaboloma/fisiologia , Metabolômica/métodos , Adulto , Doença Crônica , Feminino , Humanos , Masculino , Adulto Jovem
8.
Angew Chem Int Ed Engl ; 60(43): 23193-23196, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34460127

RESUMO

Direct enantioselective hydrogenation of unsaturated compounds to generate chiral three-dimensional motifs is one of the most straightforward and important approaches in synthetic chemistry. We realized the Ru(II)-NHC-catalyzed asymmetric hydrogenation of 2-quinolones under mild reaction conditions. Alkyl-, aryl- and halogen-substituted optically active dihydro-2-quinolones were obtained in high yields with moderate to excellent enantioselectivities. The reaction provides an efficient and atom-economic pathway to construct simple chiral 3,4-dihydro-2-quinolones. The desired products could be further reduced to tetrahydroquinolines and octahydroquinolones.

9.
Angew Chem Int Ed Engl ; 60(24): 13677-13681, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-33844391

RESUMO

We report an enantio- and diastereoselective, complete hydrogenation of multiply substituted benzofurans in a one-pot cascade catalysis. The developed protocol facilitates the controlled installation of up to six new defined stereocenters and produces architecturally complex octahydrobenzofurans, prevalent in many bioactive molecules. A unique match of a chiral homogeneous ruthenium-N-heterocyclic carbene complex and an in situ activated rhodium catalyst from a complex precursor act in sequence to enable the presented process.

10.
J Chromatogr Sci ; 59(8): 758-761, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-33420497

RESUMO

OBJECTIVE: This study aimed to establish an ion chromatography for the simultaneous determination of nitrite and azide ions in valsartan. METHODS: Dionex IonpacAG18 (4 × 50 mm2) and Dionex IonpacAS18 (4 × 250 mm2) were used as the 2D guard column and analytical column, respectively. Dionex AMGTMC18 (4 × 30 mm2) was used as a 1D pre-separation column and Dionex UTAC-ULP1 as the concentration column. KOH solution generated by an online eluent generator (EG) was used as the 2D mobile phase, and gradient elution was performed at 1 mL/min. Water and acetonitrile were used as 1D mobile phase, and gradient elution was performed at 0.5 mL/min. Suppressed conductivity detector (suppressor, ASRS 300 4 mm) was used for detection. The column temperature was 30°C, while that of the detector was 35°C. RESULTS: This method showed satisfactory reproducibility and recovery. The linear range and the correlation coefficient for both nitrite and azide ions were 0.01-0.2 mg/L and 0.9998, respectively. However, the recovery rate was 85-115% for nitrite and 90-110% for azide ions. CONCLUSION: This method was suitable for the simultaneous determination of nitrite and azide ions in valsartan and other sartan drugs.


Assuntos
Azidas , Nitritos , Cromatografia por Troca Iônica , Reprodutibilidade dos Testes , Valsartana
11.
iScience ; 23(3): 100966, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32199292

RESUMO

The Suzuki-Miyaura coupling is a fundamentally important transformation in modern organic synthesis. The development of new reaction modes for new chemical accessibility and higher synthetic efficiency is still the consistent pursuance in this field. An efficient Suzuki-Miyaura coupling enabled by a controllable 1,4-palladium migration was realized to afford stereodefined multisubstituted olefins and 1,3-dienes. The reaction exhibits remarkable broad substrate scope, excellent functional-group tolerance, versatile conversion with obtained products, and easy scalability. The practicality of this method is highlighted by the aggregation-induced emission feature of the produced olefins and 1,3-dienes, as well as the capability of affording geometric isomer pairs with a marked difference on photoluminescent quantum yield values.

12.
RSC Adv ; 10(42): 25200-25208, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35517474

RESUMO

Boron carbonitride (BCN) nanofibers with rapid and efficient adsorption performance were prepared by electrospinning technology. TEM, XRD, XPS and N2 adsorption-desorption isotherms were performed to study the microstructure of the nanofibers. The results showed that the BCN fibers synthesized at 1000 °C (BCN-1000) have good crystallinity and high specific surface areas (403 m2 g-1). BCN-1000 nanofibers adsorb 70% of amino black 10B (AB-10B) within 10 minutes and reach adsorption equilibrium within 60 minutes. Compared with previous reports, it is found that the adsorption rate of BCN-1000 nanofibers to amino black (AB-10B) is much higher than that of other adsorbents. And BCN nanofibers exhibit a large adsorption capacity (625 mg g-1). In addition, the process of AB-10B adsorption on BCN nanofibers was systematically investigated, which was in accordance with the pseudo-second-order kinetics model and Langmuir isotherm model.

13.
Angew Chem Int Ed Engl ; 58(11): 3387-3391, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30644152

RESUMO

The asymmetric rhodium-catalyzed alkenylation of enones and imines with arylboronic acids has been developed. A highly controllable aryl to vinyl 1,4-rhodium migration is the key step. Stereodefined vinyl moieties were installed in excellent enantioselectivies for most examined examples. DFT calculations reveal that the driving force of this rhodium migration is a kinetically favored process.

14.
J Pharm Pharmacol ; 71(2): 220-229, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30298631

RESUMO

OBJECTIVES: The objective of this paper was to explore the effects of Radix isatidis polysaccharide (RIP) extracted from Radix isatis on alleviating insulin resistance. METHODS: The insulin resistance models of 3T3-L1 preadipocytes and type 2 diabetic rats were established to evaluate the insulin resistance activity of RIP. KEY FINDINGS: Radix isatidis polysaccharide within the concentration range of 25-100 µg/ml could reduce cell supernatant glucose and TNF-α levels (P < 0.01) and increase the expression of PI-3K P85, Glut4, IRS-1 and Akt protein in symptoms of IR 3T3-L1 preadipocytes. In the meantime, RIP contributed to relieve the weight loss of diabetic rats whose liver weight and liver index were decreased due to the effects of RIP. Experiments in rats also showed that RIP had capacity in reduced serum TC, TG, LDL-C, FFA, FBG, FINS, MDA, ALT, AST activities and increased serum HDL-C, SOD, ISI (P < 0.05 or 0.01). In addition, the oral glucose tolerance in rats was improved (P < 0.05) and liver damage was restored due to RIP. CONCLUSIONS: Radix isatidis polysaccharide significantly alleviates insulin resistance in 3T3-L1 preadipocytes and type 2 diabetic rats. These beneficial effects of RIP may associate with their roles in improving the glucose metabolism, lipid metabolism and oxidative stress.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Resistência à Insulina , Polissacarídeos/farmacologia , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/química , Teste de Tolerância a Glucose , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas , Polissacarídeos/administração & dosagem , Polissacarídeos/isolamento & purificação , Ratos , Ratos Wistar
15.
ACS Appl Mater Interfaces ; 11(1): 1283-1293, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30525398

RESUMO

Recently, flexible and wearable devices are increasingly in demand and graphene has been widely used due to its exceptional chemical, mechanical and electrical properties. Building complex buckling patterns of graphene is an essential strategy to increase its flexible and stretchable properties. Herein, a facile dimensionally controlled four-dimensional (4D) shrinking method was proposed to generate hierarchical reduced graphene oxide (rGO) buckling patterns on curved substrates mimicking different parts of the uniforms. The reduced graphene oxide ridges (rGORs) generated on the spherical substrate seem isotropic, while those generated on the cylindrical substrate are obviously more hierarchical or oriented, especially when the cylindrical substrate are shrinking via two steps. The oriented rGORs are superhydrophobic and strain sensitive but obviously anisotropic along the axial and circumferential directions. The sensitivity of rGORs along the axial direction is much higher than those along the circumferential direction. In addition, the intrinsic solvent barrier property of graphene enables the crack-free rGORs an excellent chemical protective performance, withstanding DCM immersion for more than 2.5 h. The flexible rGORs-based strain sensors can be used to detect both large and subtle human motions and activities by achieving high sensitivity (maximum gauge factor up to 48), high unidirectional stretchability (300-530%), and ultrahigh areal stretchability (up to 2690%). Excellent durability was also demonstrated for human motion monitoring with resistance to hand rubbing, ultrasonic cleaning, machine washing, and chemical immersion.

16.
Angew Chem Int Ed Engl ; 57(20): 5871-5875, 2018 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-29573527

RESUMO

An efficient aryl to vinyl 1,4-palladium migration/Heck sequence was developed for the stereoselective synthesis of 1,3-dienes. High stereoselectivity was observed not only for 1,3-dienes bearing two similar aryl groups at terminal positions, but also for those with configurations shown to be unfavorable with previous methods.

17.
ACS Nano ; 11(7): 6843-6852, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28582627

RESUMO

Gyrification in the human brain is driven by the compressive stress induced by the tangential expansion of the cortical layer, while similar topographies can also be induced by the tangential shrinkage of the spherical substrate. Herein we introduce a simple three-dimensional (3D) shrinking method to generate the cortex-like patterns using two-dimensional (2D) graphene oxide (GO) as the building blocks. By rotation-dip-coating a GO film on an air-charged latex balloon and then releasing the air slowly, a highly folded hydrophobic GO surface can be induced. Wrinkling-to-folding transition was observed and the folding state can be easily regulated by varying the prestrain of the substrate and the thickness of the GO film. Driven by the residue stresses stored in the system, sheet-to-tube actuating occurs rapidly once the bilayer system is cut into slices. In response to some organic solvents, however, the square bilayer actuator exhibits excellent reversible, bidirectional, large-deformational curling properties on wetting and drying. An ultralarge curvature of 2.75 mm-1 was observed within 18 s from the original negative bending to the final positive bending in response to tetrahydrofuran (THF). In addition to a mechanical hand, a swimming worm, a smart package, a bionic mimosa, and two bionic flowers, a crude oil collector has been designed and demonstrated, aided by the superhydrophobic and superoleophilic modified GO surface and the solvent-responsive bilayer system.

18.
J Am Chem Soc ; 138(9): 2897-900, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26899435

RESUMO

The aryl to vinyl palladium 1,4-migration was realized for the first time. The generated alkenyl palladium species was trapped by diboron reagents under Miyaura borylation conditions, providing a new method to synthesize ß,ß-disubstituted vinylboronates. The excellent regioselectivity and broad substrate scope were observed for this novel transformation.

19.
Chem Commun (Camb) ; 51(42): 8773-6, 2015 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-25912603

RESUMO

A highly diastereo- and enantioselective rhodium-catalyzed arylation of cyclobutenes for the efficient synthesis of chiral cyclobutanes has been developed. Chiral diene ligands exhibited excellent capability for the reaction diastereoselectivity control.


Assuntos
Alcadienos/química , Ciclobutanos/síntese química , Compostos Organometálicos/química , Ródio/química , Catálise , Cristalografia por Raios X , Ciclobutanos/química , Ligantes , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo
20.
ACS Appl Mater Interfaces ; 6(24): 22673-9, 2014 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-25470597

RESUMO

Centimeters-long SiC nanowire could be a strong "bridge" between microworld and macroworld due to its unique morphology, excellent chemical stability, and intriguing physical properties. Here we present a novel "paperlike" material-free-standing SiC nanopaper fabricated by acetone-assisted compression of centimeters-long SiC nanowires. The resistance of this new paperlike material linearly increases with increasing environmental relative humidity in a very short time. We suggest that adsorption of water molecules on SiC nanopaper surface led to fast electron transfer between SiC nanopaper and water layer, which indicates that SiC nanopaper could be applied to high-performance humidity sensor in harsh environment.

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