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1.
Comput Intell Neurosci ; 2021: 7742700, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335725

RESUMO

Modern urban landscape is a simple ecosystem, which is of great significance to the sustainable development of the city. This study proposes a landscape information extraction model based on deep convolutional neural network, studies the multiscale landscape convolutional neural network classification method, constructs a landscape information extraction model based on multiscale CNN, and finally analyzes the quantitative effect of deep convolutional neural network. The results show that the overall kappa coefficient is 0.91 and the classification accuracy is 93% by calculating the confusion matrix, production accuracy, and user accuracy. The method proposed in this study can identify more than 90% of water targets, the user accuracy and production accuracy are 99.78% and 91.94%, respectively, and the overall accuracy is 93.33%. The method proposed in this study is obviously better than other methods, and the kappa coefficient and overall accuracy are the best. This study provides a certain reference value for the quantitative evaluation of modern urban landscape spatial scale.

2.
Huan Jing Ke Xue ; 42(7): 3442-3450, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212671

RESUMO

Based on Landsat satellite remote sensing images, this study interprets land use changes in the Yangtze River Delta (YRD) region from 2000 to 2018. Combined with changes in nitrogen fertilizer application, the changes in ammonia emissions from farmland ecosystem due changes in land use and nitrogen fertilizer application were further investigated. The results show that along with the rapid urbanization process, the area of cultivated land in the YRD region has gradually decreased from 276269 km2 (49% of total land area) in 2000 to 244001 km2 (44%) in 2018. The effects of changes in land use and nitrogen fertilizer application on ammonia emissions from farmland ecosystems mainly include emissions from soil background and nitrogen fertilizer application. From 2000 to 2018, ammonia emissions due to the application of nitrogen fertilizer decreased from 690 kt·a-1 to 541 kt·a-1 (relative decrease by 22%), while the ammonia emissions from the soil background reduced from 32 kt·a-1 to 29 kt·a-1 (decrease by 9%). During the past 20 years, urbanization in the YRD region has accelerated, and the area of cultivated land and the total amount of nitrogen fertilizer application have significantly reduced, thus resulting in reductions in ammonia emissions from the farmland ecosystem.


Assuntos
Amônia , Ecossistema , Agricultura , Amônia/análise , China , Fertilizantes/análise , Nitrogênio/análise , Rios , Solo
3.
World J Surg Oncol ; 19(1): 195, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215279

RESUMO

BACKGROUND: To describe the techniques and outcomes of complete transperitoneal laparoscopic nephroureterectomy (CTLNU) for upper urinary tract urothelial carcinoma (UTUC) in a single position. MATERIALS AND METHODS: Those patients with localized UTUC were included, among which 50 cases had CTLNU while 48 cases had laparoscopic nephroureterectomy with open bladder cuff excision (LNOBE). The clinical data were collected and analyzed retrospectively. RESULTS: All 98 patients underwent successful procedures of radical nephroureterectomy without transferring into open surgery. No significant difference was found among baseline clinical characteristics. Compared with the LNOBE group, the CTLNU group had a shorter operative time (98.5±40.3 min vs. 132.4±60.2 min), less blood loss (60.4±20.3 ml vs. 150.6±50.2 ml), shorter length of hospital stay (5.3±2.2 days vs. 8.1±2.3 days), and shorter incision (6.3±1.2 cm vs. 11.5±3.2 cm). The disease-related outcomes such as pathological stage, tumor grade, and recurrence rate were similar between the two groups. CONCLUSIONS: The CTLNU in a single position had advantages of shorter operation time, less blood loss, and shorter incision length. This surgical technique is a more minimally invasive, simplified, and effective way to perform the radical nephroureterectomy.


Assuntos
Carcinoma de Células de Transição , Laparoscopia , Ureter , Neoplasias Ureterais , Neoplasias da Bexiga Urinária , Carcinoma de Células de Transição/cirurgia , Humanos , Recidiva Local de Neoplasia , Nefrectomia , Nefroureterectomia , Prognóstico , Estudos Retrospectivos , Neoplasias Ureterais/cirurgia
4.
Oxid Med Cell Longev ; 2021: 9973457, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234888

RESUMO

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are common critical diseases. Bone marrow mesenchymal stem cell (BMSC) transplantation is previously shown to effectively rescue injured lung tissues. The therapeutic mechanism of BMSC-derived exosomes is not fully understood. Here, we investigated the BMSC-derived exosomal microRNAs (miRNAs) on effecting lipopolysaccharide- (LPS-) induced ALI and its mechanism. In vitro, rat alveolar macrophages were treated with or without exosomes in the presence of 10 µg/ml LPS for 24 h. Cell viability was determined with Cell Counting Kit-8 assay. Apoptotic ratio was determined with TUNEL and Annexin V-FITC/PI double staining. The levels of miR-384-5p and autophagy-associated genes were measured by RT-qPCR and western blot. Autophagy was observed by TEM and assessed by means of the mRFP-GFP-LC3 adenovirus transfection assay. In vivo, we constructed LPS-induced ALI rat models. Exosomes were injected into rats via the caudal vein or trachea 4 h later after LPS treatment. The lung histological pathology was determined by H&E staining. Pulmonary vascular permeability was assessed by wet-to-dry weight ratio and Evans blue dye leakage assay, and inflammatory cytokines in serum and BALF were measured by ELISA. Furthermore, the therapeutic mechanism involved in miR-384-5p and Beclin-1 was determined. The results showed that BMSC-derived exosomes were taken up by the alveolar macrophages and attenuated LPS-induced alveolar macrophage viability loss and apoptosis. Exosomes effectively improved the survival rate of ALI rats within 7 days, which was associated with alleviating lung pathological changes and pulmonary vascular permeability and attenuating inflammatory response. Furthermore, this study for the first time found that miR-384-5p was enriched in BMSC-derived exosomes, and exosomal miR-384-5p resulted in relieving LPS-injured autophagy disorder in alveolar macrophages by targeting Beclin-1. Therefore, exosomal miR-384-5p could be demonstrated as a promising therapeutic strategy for ALI/ARDS.

5.
JACC Cardiovasc Interv ; 14(13): 1450-1462, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34238555

RESUMO

OBJECTIVES: The aim of the present study was to evaluate the safety and efficacy of thinner strut Firesorb (100/125 µm) sirolimus-eluting bioresorbable scaffolds (BRS) versus cobalt-chromium everolimus-eluting stents (CoCr-EES) in patients with coronary artery disease. BACKGROUND: First-generation thicker strut BRS were associated with unexpected device-related adverse outcomes at long-term follow-up. METHODS: Eligible patients with 1 or 2 de novo noncomplex coronary lesions were randomized to the Firesorb BRS group or CoCr-EES group in a 1:1 ratio. The primary endpoint was 1-year angiographic in-segment late loss (LL), powered for noninferiority testing. The key secondary endpoint was the 1-year proportion of covered struts assessed on optical coherence tomography, powered for noninferiority and subsequent superiority testing. RESULTS: A total of 433 participants from 28 Chinese centers were randomized to the Firesorb BRS group (n = 215) or CoCr-EES group (n = 218). Patient-level 1-year in-segment LL was 0.17 ± 0.27 mm in the Firesorb BRS group and 0.18 ± 0.37 mm in the CoCr-EES group (difference -0.01 mm; 95% confidence interval [CI]: -0.07 to 0.06; pnoninferiority < 0.0001) in the intention-to-treat population and was 0.17 ± 0.27 mm in the Firesorb BRS group and 0.19 ± 0.37 mm in the CoCr-EES group (difference -0.005 mm; 95% CI: -0.07 to 0.06; pnoninferiority < 0.0001) in the per-protocol set. The proportion of covered struts was 99.3% in the Firesorb BRS group and 98.8% in the CoCr-EES group (difference 0.8%; 95% CI: -0.5% to 2.1%; pnoninferiority < 0.0001; psuperiority = 0.21). One-year clinical outcomes were similar between groups. CONCLUSIONS: The thinner strut Firesorb BRS was noninferior to the CoCr-EES for the primary endpoint of 1-year angiographic in-segment LL and the key secondary endpoint of 1-year proportion of covered struts by optical coherence tomography. (A Trial of Firesorb in Patients With Coronary Artery Disease: FUTURE-II [FUTURE-II]; NCT02890160).

6.
RNA Biol ; 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34241580

RESUMO

Melanoma is considered as the most frequent primary malignancy occurring in skin. Accumulating studies have suggested that long non-coding RNAs (lncRNAs) play critical parts in multiple cancers. In this study, we explored the molecular mechanism of ZBED3 antisense RNA 1 (ZBED3-AS1) in melanoma. We observed that ZBED3-AS1 expression was remarkably up-regulated in melanoma tissues, and high ZBED3-AS1 level was linked to unsatisfactory survival of melanoma patients. Then, we discovered that ZBED3-AS1 was overexpressed in melanoma cells compared with human epidermal melanocytes. In addition, loss-of-function assays verified that ZBED3-AS1 knockdown restrained cell proliferation, migration, epithelial-mesenchymal transition (EMT) and stemness in melanoma. In addition, signal transducer and activator of transcription 3 (STAT3), which also showed tumor-facilitating functions in melanoma, was confirmed as a transcriptional activator of ZBED3-AS1. Moreover, ZBED3-AS1 enhanced the expression of AT-rich interaction domain 4B (ARID4B) through sequestering miR-381-3p. Importantly, we further confirmed that ZBED3-AS1 promoted the malignant progression of melanoma by regulating miR-381-3p/ARID4B axis to activate the phosphatidylinositol 3-kinase/AKT serine/threonine kinase (PI3K/AKT) signaling pathway. In a word, our research might provide a novel therapeutic target for melanoma.

7.
Langmuir ; 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34233119

RESUMO

CuCo2O4, a type of promising lithium-ion storage material, exhibits high electrochemical properties in lithium-ion batteries and enormous economic benefits. However, its practical application is limited by problems such as structural collapse and electrochemical stability during the charging and discharging process. In this work, the reduced graphene oxide (rGO)-coated CuCo2O4 (CuCo2O4/rGO) hollow microspheres were successfully prepared by electrostatic self-assembly. The CuCo2O4/rGO electrode shows an outstanding capability for lithium-ion storage and a remarkable rate capacity, e.g., 445 mA h g-1 at 5 A g-1. After 150 cycles at 0.1 A g-1, the reversible capacity of the CuCo2O4/rGO electrode is as high as 1080 mA h g-1, and it can still retain about 530 mA h g-1 in the 400th cycle at 1 A g-1. The hollow microspheres with mesoporous shells can cause electrolyte penetration into the spherical shell to effectively shorten the transfer distance of lithium ions, and the encapsulation of graphene improves the conductivity and stability of CuCo2O4, which endows CuCo2O4/rGO with a wonderful Li+ storage performance. It is proved that this is an efficient method to improve the electrochemical performance of metal compounds for better applications in energy storage.

8.
Rev Sci Instrum ; 92(4): 043709, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243459

RESUMO

Here, we report our newly built table-top ultrafast extreme ultraviolet (EUV) photoemission electron microscope. The coherent ultrafast EUV light is served by a single order harmonic, which is generated by the interaction between the intense 800-nm femtosecond laser and noble gases in the hollow core fiber. The required order of the harmonic is selected out by a single grating in the off-plane mount and focused on the sample in the ultrahigh vacuum chamber of the photoemission electron microscope. Using metal gold and copper samples, the spatial resolution is calibrated to be better than 50 nm and the energy resolution is calibrated to be better than 300 meV. This microscope provides an advanced tool for studying electron dynamics covering the full Brillouin zone of solid materials with ultrahigh time, space, and energy resolution.

9.
Artigo em Inglês | MEDLINE | ID: mdl-34328727

RESUMO

Metal-organic frameworks (MOF) are promising media for achieving solid-state Mg2+ conduction and developing a magnesium-based battery. To this end, the chemical behavior and transport properties of an Mg(TFSI)2/DME electrolyte system inside Mg-MOF-74 were studied by density functional theory (DFT). We found that inside the MOF chemical environment, solvent and anion molecules occupy the coordinatively unsaturated open metal sites of Mg-MOF-74, while Mg2+ ions adsorb directly onto the carboxylate group of the MOF organic linker. These predicted binding geometries were further corroborated by IR spectroscopy. We computed the free energies of desolvation of Mg2+ ions inside MOF to investigate the capacity of Mg-MOF-74 thin film to act as a separator for selective Mg2+ transport. We showed that Mg-MOF-74 could facilitate partial, but not full, desolvation of Mg2+. We found that the dominant minimum-energy pathway (MEP) for Mg2+ conduction inside Mg-MOF-74 corresponds to a "solvent hopping" mechanism, with an energy barrier of 4.4 kcal/mol. The molar conductivity of Mg2+ associated with the idealized solvent hopping mechanism along the MOF one-dimensional channel was predicted to be 2.4 × 10-3 S cm-1 M-1, which is one to two orders of magnitude greater than the experimentally measured value of 1.2 × 10-4 S cm-1 M-1 (with an estimated Mg2+ concentration). We have discussed several possible factors contributing to this apparent discrepancy. The current work demonstrates the validity of the computational strategies applied and the structural models constructed for the understanding of fast and selective Mg2+ transport in Mg-MOF-74, which serves as a cornerstone for studying transport of multivalent ions in MOFs. Furthermore, it provides detailed molecular-level insights that are not yet accessible experimentally.

10.
Chemosphere ; 285: 131519, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34329128

RESUMO

This study chose Oak woodchips and gravel as media filter to enhance the denitrification in the bioretention system (saturated zone 7.7 L) treating synthetic stormwater runoff. It revealed that the denitrification process mainly occurred during the drying phase and enlarging volume of saturated zones to retain more stormwater during storm event was the direct method to promote nitrogen removal of the bioretention system. Nevertheless, it was noted that the nitrogen and dissolved organic carbon would be released into the effluent during the wetting period. The denitrification rate with different nitrate nitrogen (NO3-N) concentrations did not show the obvious change with zero order kinetics constant of 2.91 mg/L∙d on average. Furthermore, it confirmed that woodchips were degraded and converted to volatile fatty acids (VFAs), especially acetic acid as carbon source, further utilized by the denitrifying bacteria, such as Dechloromonas, Acidoborax, Pseudomonas, Denitratisoma and Acinetobacter. In addition, genera of Lachnospiraceae and Lactobacillus, which had the ability to degrade the macromolecular organic components into low molecular VFAs, were observed in the woodchips bioretention system.

11.
Genome Res ; 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34330789

RESUMO

Uniparental embryos derived from only the mother (gynogenetic, GG) or the father (androgenetic, AG) are unique models for studying genomic imprinting and parental contributions to embryonic development. Human parthenogenetic embryos can be obtained following artificial activation of unfertilized oocytes, but the production of AG embryos by injection of two sperm into one denucleated oocyte leads to an extra centriole, resulting in multipolar spindles, abnormal cell division, and developmental defects. Here, we improved androgenote production by transferring the male pronucleus from one zygote into another haploid androgenote to prevent extra centrioles and successfully generated human diploid androgenetic embryos capable of developing into blastocysts with an identifiable inner cell mass (ICM) and trophectoderm (TE). The GG embryos were also generated. The zygotic genome was successfully activated in both the AG and GG embryos. DNA methylome analysis showed that the GG blastocysts partially retain the oocyte transcription-dependent methylation pattern, whereas the AG blastocyst methylome showed more extensive demethylation. The methylation states of most known imprinted differentially methylated regions (DMRs) were recapitulated in the AG and GG blastocysts. Novel candidate imprinted DMRs were also identified. The production of uniparental human embryos followed by transcriptome and methylome analysis is valuable for identifying parental contributions and epigenome memory transitions during early human development.

12.
Acta Pharm Sin B ; 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34249607

RESUMO

The COVID-19 pandemic caused by the novel SARS-CoV-2 virus has caused havoc across the entire world. Even though several COVID-19 vaccines are currently in distribution worldwide, with others in the pipeline, treatment modalities lag behind. Accordingly, researchers have been working hard to understand the nature of the virus, its mutant strains, and the pathogenesis of the disease in order to uncover possible drug targets and effective therapeutic agents. As the research continues, we now know the genome structure, epidemiological and clinical features, and pathogenic mechanism of SARS-CoV-2. Here, we summarized the potential therapeutic targets involved in the life cycle of the virus. On the basis of these targets, small-molecule prophylactic and therapeutic agents have been or are being developed for prevention and treatment of SARS-CoV-2 infection.

13.
Biomed Res Int ; 2021: 9976541, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34250094

RESUMO

Objective: Many intracranial aneurysms often have branch arteries, and it is especially important to protect them during embolization. The purpose of the present study was to evaluate the curative effect and safety of the "stilted building" technique. Methods: 25 patients with intracranial aneurysms with branch arteries that have been treated by coil embolization with the "stilted building" technique were retrospectively reviewed. Clinical follow-up was performed after endovascular treatment. Results: All 25 patients successfully underwent aneurysm embolization. During the operation, the ruptured sac and most of the body of the aneurysm were embolized using the "stilted building" technique. Immediate imaging showed that the blood flow to the branch arteries from the neck or sidewall of the aneurysm was unobstructed. The mRS scores of the 25 patients during the follow-up period were mRS 0 for twenty-one patients, mRS 1 for three patients, and mRS 6 for one patient. No aneurysms recurred among the patients who completed the follow-up. Conclusions: In an aneurysm with a branch artery, when a balloon or stent cannot be effectively used to protect the branch artery, the use of "stilted building" embolization can achieve good therapeutic effects, and the short-term follow-up results are satisfactory; the technique can effectively protect branch arteries originating from aneurysms.

14.
Artigo em Inglês | MEDLINE | ID: mdl-34252033

RESUMO

Deep multiview clustering methods have achieved remarkable performance. However, all of them failed to consider the difficulty labels (uncertainty of ground truth for training samples) over multiview samples, which may result in a nonideal clustering network for getting stuck into poor local optima during the training process; worse still, the difficulty labels from the multiview samples are always inconsistent, and such a fact makes it even more challenging to handle. In this article, we propose a novel deep adversarial inconsistent cognitive sampling (DAICS) method for multiview progressive subspace clustering. A multiview binary classification (easy or difficult) loss and a feature similarity loss are proposed to jointly learn a binary classifier and a deep consistent feature embedding network, throughout an adversarial minimax game over difficulty labels of multiview consistent samples. We develop a multiview cognitive sampling strategy to select the input samples from easy to difficult for multiview clustering network training. However, the distributions of easy and difficult samples are mixed together, hence not trivial to achieve the goal. To resolve it, we define a sampling probability with a theoretical guarantee. Based on that, a golden section mechanism is further designed to generate a sample set boundary to progressively select the samples with varied difficulty labels via a gate unit, which is utilized to jointly learn a multiview common progressive subspace and clustering network for more efficient clustering. Experimental results on four real-world datasets demonstrate the superiority of DAICS over state-of-the-art methods.

15.
Inorg Chem ; 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34255966

RESUMO

A series of ß-ketoamino-based N,O-chelate half-sandwich iridium complexes with the general formula [Cp*IrClL] have been prepared in good yields. These air-insensitive iridium complexes showed desirable catalytic activity in an amide preparation under mild conditions. A number of amides with diverse substituted groups were furnished in a one-pot reaction with good-to-excellent yields through an amidation reaction of NH2OH·HCl with aldehydes in the presence of these iridium(III) precursors. The excellent catalytic activity, mild reaction conditions, and broad substrate scope gave this type of iridium catalyst potential for use in industry. All of the obtained iridium complexes were well characterized by different spectroscopy techniques. The exact molecular structure of complex 3 has been confirmed by single-crystal X-ray analysis.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34199383

RESUMO

AIM: There is an ongoing debate as to what extent antimicrobial resistance (AMR) can be transmitted from dietary to humans via the consumption of food products. We investigated this association between dietary and global spreading carbapenem-resistant gene blaNDM Methods: We did a cross-sectional study to assess the risk factors for carrier of blaNDM in health community. Healthy adults were recruited from the residents attending Community Healthcare Service in Shenzhen City (Guangdong Province, China), through 1February 2018 to 31December 2019, and 718 pre-participants were included in this study. Questionnaire were obtained and the qualitative food frequency questionnaire (Q-FFQ) were used to assess dietary intake. qPCR was applied to confirm the carrier of blaNDM in participants'fecal samples. Multivariable logistic regression was used to estimate the odds ratio (OR) and 95% confidence interval (95% CI) of each outcome according to each dietary factor before and after prosperity score matching (PSM). RESULTS: we showed that a high intake of coarse grain (OR 1.003; 95% CI 1.001-1.005, p < 0.01) and root and tuber crops (OR 1.003; 95% CI 1.001-1.004, p < 0.05) were independent risk factor for blaNDM carrier in health communities, suggesting a possible transfer of AMRbetweendietary andhumans. Surprisingly, we also showed an association between a higher intake of poultry as a protective, which may be explained by the beneficial effects on the gut microbiota. CONCLUSION: Dietary factors such as intake of coarse grain, root and tuber crops and poultry were associated with blaNDM carrier in health communities. The influence of dietary factorson blaNDM carrier in the present study provides insights for the tangible dietary advice with guidelines to the routine of people with the risk of blaNDM carrier. This demonstrates the role of dietary intake in the prevention of blaNDM carrier, since prevention is the best way to control modifiable risk factors. A lower carrier rate of blaNDM is helpful to reduce the possibility of transmission and pathogenicity. Further studies on food, microbiota and antimicrobial resistance are necessary to confirm this possible association and unravel underlying mechanisms.


Assuntos
Dieta , Microbioma Gastrointestinal , Adulto , China/epidemiologia , Estudos Transversais , Humanos , Fatores de Risco
17.
Biomed Res Int ; 2021: 6681491, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34195279

RESUMO

Background: Although hypothyroidism during pregnancy may develop grave outcomes for both mothers and offspring, management of which is still a challenge due to the insufficient understanding of this disease. The close correlation between hypothyroidism and preeclampsia is well documented, suggesting that preeclampsia is a potential risk factor for the development of maternal hypothyroidism. However, the exact role of preeclampsia in gestational hypothyroidism is still obscure. Objective: In this study, we explored the possible mechanisms of the effect of preeclampsia on thyroid function of maternal rats. Methods: Thirty pregnant rats were randomly divided into normal pregnancy control (NOP), preeclampsia (PE), and preeclampsia supplemented with amlodipine besylate (PEAml). NG-Nitro-L-arginine-methyl ester was used to induce preeclamptic symptoms. On gestational day 21, rats were sacrificed, and then, the ultrastructure of the thyroid gland, type 1 iodothyronine deiodinase (Dio1) expression, and serum-free thyroxine (FT4), free triiodothyronine (FT3), and thyroid stimulation hormones (TSH) were assessed. Results: Compared to NOP rats, results of PE rats showed that thyroid follicular cells' ultrastructure was damaged; both hepatic Dio1 mRNA and protein levels were decreased. Interestingly, these changes were ameliorated in PEAml rats. Additionally, FT4, FT3, and TSH levels have no significant differences among groups. Conclusion: These findings indicated that preeclampsia could disrupt synthesis, secretion, and metabolism function of thyroid hormones by damaging thyroid follicular cells and interfering Dio1 expression.

18.
Analyst ; 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34296232

RESUMO

Surface-enhanced Raman scattering (SERS) has become one of the most sensitive analytical techniques for identifying the chemical components, molecular structures, molecular conformations, and the interactions between molecules. However, great challenges still need to be addressed until it can be widely accepted by the absolute quantification of analytes. Recently, many efforts have been devoted to addressing these issues via various electromagnetic (EM), chemical (CM), and EM-CM hybrid coupling enhancement strategies. In comparison with uncoupled SERS devices, they offer key advantages in terms of sensitivity, reproducibility, uniformity, stability, controllability and reliability. This review provides an in-depth analysis of coupled SERS devices, including coupling enhancement mechanisms, materials and approaches. Finally, we also discuss the remaining bottlenecks and possible strategies for the development of coupling-enhanced SERS devices in the future.

19.
J Agric Food Chem ; 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34296617

RESUMO

pH shift is an effective technique for modifying functional properties of food proteins. However, it can increase lysinoalanine (LAL) content under alkali conditions, thus limiting the use of proteins. This study investigated the inhibition effect of ultrasonic parameters on LAL formation in rapeseed protein isolates (RPI) during pH shift treatment (pH-ST). Results showed that the content of LAL decreased by 49.5% and 74.1%, following the use of ultrasound (28 kHz, 40 W/L, 40 °C, and 30 min) under alkali and acidic treatment, respectively. Structural analysis showed that after ultrasonic irradiation, increased sulfhydryl groups and amino acids reduced the dehydroalanine and, thus, decreased LAL content. Particle size, secondary structure, and microstructure (SEM, AFM) analyses showed relative dispersion in protein distribution, reducing intermolecular or intramolecular cross-linking, thereby lowering the LAL content. Thus, ultrasonic-aided pH-ST may be an operational technique toward minimizing LAL formation in RPI.

20.
Sci Rep ; 11(1): 14794, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34285326

RESUMO

Force enhancement is one kind of myogenic spontaneous fasciculation in lengthening preload striated muscles. In cardiac muscle, the role of this biomechanical event is not well established. The physiological passive property is an essential part for maintaining normal diastole in the heart. In excessive preload heart, force enhancement relative erratic passive properties may cause muscle decompensating, implicate in the development of diastolic dysfunction. In this study, the force enhancement occurrence in mouse cardiac papillary muscle was evaluated by a microstepping stretch method. The intracellular Ca2+ redistribution during occurrence of force enhancement was monitored in real-time by a Flou-3 (2 mM) indicator. The force enhancement amplitude, the enhancement of the prolongation time, and the tension-time integral were analyzed by myography. The results indicated that the force enhancement occurred immediately after active stretching and was rapidly enhanced during sustained static stretch. The presence of the force and the increase in the amplitude synchronized with the acquisition and immediate transfer of Ca2+ to adjacent fibres. In highly preloaded fibres, the enhancement exceeded the maximum passive tension (from 4.49 ± 0.43 N/mm2 to 6.20 ± 0.51 N/mm2). The occurrence of force enhancement were unstable in each static stretch. The increased enhancement amplitude combined with the reduced prolongation time to induce a reduction in the tension-time integral. We concluded that intracellular Ca2+-synchronized force enhancement is one kind of interruption event in excessive preload cardiac muscle. During the cardiac muscle in its passive relaxation period, the occurrence of this interruption affected the rhythmic stability of the cardiac relaxation cycle.

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