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1.
Nat Commun ; 15(1): 7682, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227380

RESUMO

The inversion of substrate size specificity is an evolutionary roadblock for proteins. The Duf4243 dioxygenases GedK and BTG13 are known to catalyze the aromatic cleavage of bulky tricyclic hydroquinone. In this study, we discover a Duf4243 dioxygenase PaD that favors small monocyclic hydroquinones from the penicillic-acid biosynthetic pathway. Sequence alignments between PaD and GedK and BTG13 suggest PaD has three additional motifs, namely motifs 1-3, distributed at different positions in the protein sequence. X-ray crystal structures of PaD with the substrate at high resolution show motifs 1-3 determine three loops (loops 1-3). Most intriguing, loops 1-3 stack together at the top of the pocket, creating a lid-like tertiary structure with a narrow channel and a clearly constricted opening. This drastically changes the substrate specificity by determining the entry and binding of much smaller substrates. Further genome mining suggests Duf4243 dioxygenases with motifs 1-3 belong to an evolutionary branch that is extensively involved in the biosynthesis of natural products and has the ability to degrade diverse monocyclic hydroquinone pollutants. This study showcases how natural enzymes alter the substrate specificity fundamentally by incorporating new small motifs, with a fixed overall scaffold-architecture. It will also offer a theoretical foundation for the engineering of substrate specificity in enzymes and act as a guide for the identification of aromatic dioxygenases with distinct substrate specificities.


Assuntos
Motivos de Aminoácidos , Dioxigenases , Especificidade por Substrato , Dioxigenases/metabolismo , Dioxigenases/genética , Dioxigenases/química , Cristalografia por Raios X , Hidroquinonas/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Sequência de Aminoácidos , Modelos Moleculares , Alinhamento de Sequência
2.
ACS Appl Mater Interfaces ; 16(35): 46280-46288, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39162615

RESUMO

Layered materials have emerged as stars in the realm of nanomaterials, showcasing exceptional versatility in various fields. This investigation employed a thermally driven method to intercalate cobalt (Co) into the van der Waals gaps of (CuI)0.002Bi2Te2.7Se0.3 crystals and investigated the mechanism by which the intercalated Co enhances the thermoelectric performance of the material. Co intercalation decreases the carrier concentration, thereby improving the Seebeck coefficient and decreasing both the mobility and the electrical conductivity. These effects result in a significant enhancement of the power factor above 400 K. Theoretical electronic structure calculations provide insights into the role of Co in this material. Additionally, the presence of intercalated Co significantly enhances phonon scattering, thereby boosting the thermoelectric figure-of-merit, ZT to 1.33 at 350 K for 0.17% Co intercalation. These findings highlight the potential of Co incorporation for improving the thermoelectric energy efficiency of n-type Bi2Te2.7Se0.3, offering avenues for further optimization in thermoelectric applications.

3.
Sensors (Basel) ; 24(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39123878

RESUMO

With the development of smart agriculture, autopilot technology is being used more and more widely in agriculture. Because most of the current global path planning only considers the shortest path, it is difficult to meet the articulated steering tractor operation needs in the orchard environment and address other issues, so this paper proposes a hybrid algorithm of an improved bidirectional search A* algorithm and improved differential evolution genetic algorithm(AGADE). First, the integrated priority function and search method of the traditional A* algorithm are improved by adding weight influence to the integrated priority, and the search method is changed to a bidirectional search. Second, the genetic algorithm fitness function and search strategy are improved; the fitness function is set as the path tree row center offset factor; the smoothing factor and safety coefficient are set; and the search strategy adopts differential evolution for cross mutation. Finally, the shortest path obtained by the improved bidirectional search A* algorithm is used as the initial population of an improved differential evolution genetic algorithm, optimized iteratively, and the optimal path is obtained by adding kinematic constraints through a cubic B-spline curve smoothing path. The convergence of the AGADE hybrid algorithm and GA algorithm on four different maps, path length, and trajectory curve are compared and analyzed through simulation tests. The convergence speed of the AGADE hybrid algorithm on four different complexity maps is improved by 92.8%, 64.5%, 50.0%, and 71.2% respectively. The path length is slightly increased compared with the GA algorithm, but the path trajectory curve is located in the center of the tree row, with fewer turns, and it meets the articulated steering tractor operation needs in the orchard environment, proving that the improved hybrid algorithm is effective.

4.
Materials (Basel) ; 17(15)2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39124429

RESUMO

Room temperature drop hammer impact and compression after impact (CAI) experiments were conducted on carbon fiber-epoxy resin (CF/EP) composites to investigate the variation in impact load and absorbed energy, as well as to determine the residual compressive strength of CF/EP composites following impact damage. Industrial CT scanning was employed to observe the damage morphology after both impact and compression, aiding in the study of impact-damage and compression-failure mechanisms. The results indicate that, under the impact load, the surface of a CF/EP composite exhibits evident cratering as the impact energy increases, while cracks form along the length direction on the back surface. The residual compressive strength exhibits an inverse relationship with the impact energy. Impact damage occurring at an energy lower than 45 J results in end crushing during the compression of CF/EP composites, whereas energy exceeding 45 J leads to the formation of long cracks spanning the entire width of the specimen, primarily distributed symmetrically along the center of the specimen.

5.
Transl Pediatr ; 13(6): 938-945, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38984021

RESUMO

Background: In 2009, the clinical practice guidelines (CPG) were released by the American Academy of Orthopaedic Surgeons (AAOS), which outline an age-based approach for treating pediatric femoral shaft fractures (PFSF), both nonoperatively and operatively. The aim of the current study was to investigate potential disparities between the recommended treatments for PFSF based on the AAOS-CPG and the actual treatments administered in The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University. Methods: A retrospective review was conducted on the medical charts and radiographs of all PFSF treated at The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University from January 2014 to January 2022. We identified 445 children who met our inclusion criteria and evaluated their treatments according to the AAOS-CPG. Actual treatments were then compared with the treatments recommended by the AAOS-CPG. Binomial and multivariate logistic regression was used to examine whether different factors could predict the choice between operative and nonoperative management. Results: Operative treatments were undertaken in 102 of 215 (47.4%) fractures in children younger than 6 years, in 102 of 122 (83.6%) fractures in those between 6 and 12 years of age, and in 107 of 108 (99.1%) fractures in those older than 12 years. Nonoperative management was conducted in 113 of 215 (52.6%) fractures in children younger than 6 years, in 20 of 122 (16.4%) fractures in those between 6 and 12 years of age, and in 1 of 108 (0.9%) fractures in those older than 12 years of age. Surgeon decisions for non-surgery were in agreement with the CPG 52.6% of the time, whereas agreement reached 90.9% for surgical choices. Predictors of actual operative management were age (P=0.01), patient weight (P<0.001), fracture pattern (P<0.001), presence of other orthopedic injuries requiring surgery (P=0.002), and polytrauma (P=0.02). Conclusions: There was limited concordance between actual treatments and CPG recommendations, particularly for the nonoperative management of fractures in children under 6 years old. Age, patient weight, fracture pattern, presence of other orthopedic injuries requiring surgery, and polytrauma were the main predictors of our operative decision-making process.

6.
ACS Appl Mater Interfaces ; 16(31): 41495-41503, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39069916

RESUMO

This study explores the utilization of the organic conductive molecule Polypyrrole (PPy) for the modification of Indium Gallium Zinc Oxide (IGZO) nanoparticles, aiming to develop highly sensitive ozone sensors. Pyrrole (Py) molecules undergo polymerization, resulting in the formation of extended chains of PPy that graft onto the surface of IGZO nanoparticles. This interaction effectively diminishes oxygen vacancies on the IGZO surface, thereby promoting the crystallization of the IGZO (1114) facets. The resultant structure exhibits promising potential for achieving high-performance wideband semiconductor gas sensors. The IGZO/PPy device forms a Straddling Gap heterojunction, facilitating enhanced electron transfer between IGZO and ozone molecules. Notably, the adsorption and desorption of ozone gas occur efficiently at a low temperature of approximately 25 °C, obviating the need for additional energy typically associated with wide bandgap semiconductor materials. Density Functional Theory (DFT) calculations attribute this efficiency to the enhanced number of active sites for ozone adsorption, facilitated by hydrogen bonds. The substantial conductivity of PPy, combined with its planar ring structure, induces positively charged polarization on the IGZO side upon ozone adsorption. The resultant device exhibits exceptional sensitivity, boasting a 4-fold improvement compared to sensors reliant solely on IGZO. Additionally, the response time is significantly reduced by a factor of 10, underscoring the practical viability and enhanced performance of the IGZO/PPy sensor field.

7.
Nanomaterials (Basel) ; 14(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38727342

RESUMO

Thermoelectric power can convert heat and electricity directly and reversibly. Low-dimensional thermoelectric materials, particularly thin films, have been considered a breakthrough for separating electronic and thermal transport relationships. In this study, a series of Bi0.5Sb1.5Te3 thin films with thicknesses of 0.125, 0.25, 0.5, and 1 µm have been fabricated by RF sputtering for the study of thickness effects on thermoelectric properties. We demonstrated that microstructure (texture) changes highly correlate with the growth thickness in the films, and equilibrium annealing significantly improves the thermoelectric performance, resulting in a remarkable enhancement in the thermoelectric performance. Consequently, the 0.5 µm thin films achieve an exceptional power factor of 18.1 µWcm-1K-2 at 400 K. Furthermore, we utilize a novel method that involves exfoliating a nanosized film and cutting with a focused ion beam, enabling precise in-plane thermal conductivity measurements through the 3ω method. We obtain the in-plane thermal conductivity as low as 0.3 Wm-1K-1, leading to a maximum ZT of 1.86, nearing room temperature. Our results provide significant insights into advanced thin-film thermoelectric design and fabrication, boosting high-performance systems.

8.
Sci Rep ; 14(1): 11011, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744937

RESUMO

Spider silk is a promising material with great potential in biomedical applications due to its incredible mechanical properties and resistance to degradation of commercially available bacterial strains. However, little is known about the bacterial communities that may inhabit spider webs and how these microorganisms interact with spider silk. In this study, we exposed two exopolysaccharide-secreting bacteria, isolated from webs of an orb spider, to major ampullate (MA) silk from host spiders. The naturally occurring lipid and glycoprotein surface layers of MA silk were experimentally removed to further probe the interaction between bacteria and silk. Extensibility of major ampullate silk produced by Triconephila clavata that was exposed to either Microbacterium sp. or Novosphigobium sp. was significantly higher than that of silk that was not exposed to bacteria (differed by 58.7%). This strain-enhancing effect was not observed when the lipid and glycoprotein surface layers of MA silks were removed. The presence of exopolysaccharides was detected through NMR from MA silks exposed to these two bacteria but not from those without exposure. Here we report for the first time that exopolysaccharide-secreting bacteria inhabiting spider webs can enhance extensibility of host MA silks and silk surface layers play a vital role in mediating such effects.


Assuntos
Seda , Aranhas , Animais , Aranhas/microbiologia , Aranhas/metabolismo , Seda/metabolismo , Bactérias/metabolismo , Polissacarídeos Bacterianos/metabolismo
9.
Materials (Basel) ; 17(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38673165

RESUMO

The low-temperature fatigue crack propagation rate of 925A steel, as a rudder steel for polar special ships, has a crucial impact on the evaluation of the fatigue strength of polar ships. The purpose of this article is to study the fatigue crack propagation rate of 925A steel under different low-temperature conditions from room temperature (RT) to -60 °C. The material was subjected to fatigue crack propagation tests and stress intensity factor tests. The experimental tests were conducted according to the Chinese Standard of GB/T6398-2017. The results show that as the temperature decreases, the lifespan of 925A increases. Within a certain stress intensity factor, as the temperature decreases, the fatigue crack propagation rate decreases. At -60 °C, it exhibits ductile fracture; within normal polar temperatures, it can be determined that 925A meets the requirements for low-temperature fatigue crack propagation rates in polar regions. However, in some extreme polar temperatures below -60 °C, preventing brittle failure becomes a key focus of fatigue design. Finally, the fatigue crack propagation behavior at the microscale of 925A steel at low temperatures was described using fracture morphology. The experimental data can provide reference for the design of polar ships to further resist low-temperature fatigue and cold brittle fracture.

10.
Sensors (Basel) ; 24(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38544273

RESUMO

Designed to meet the demands of AGV global optimal path planning and dynamic obstacle avoidance, this paper proposes a combination of an improved A* algorithm and dynamic window method fusion algorithm. Firstly, the heuristic function is dynamically weighted to reduce the search scope and improve the planning efficiency; secondly, a path-optimization method is introduced to eliminate redundant nodes and redundant turning points in the path; thirdly, combined with the improved A* algorithm and dynamic window method, the local dynamic obstacle avoidance in the global optimal path is realized. Finally, the effectiveness of the proposed method is verified by simulation experiments. According to the results of simulation analysis, the path-planning time of the improved A* algorithm is 26.3% shorter than the traditional A* algorithm, the search scope is 57.9% less, the path length is 7.2% shorter, the number of path nodes is 85.7% less, and the number of turning points is 71.4% less. The fusion algorithm can evade moving obstacles and unknown static obstacles in different map environments in real time along the global optimal path.

11.
BMC Musculoskelet Disord ; 25(1): 188, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431562

RESUMO

BACKGROUND: Implant choice for the fixation of femoral neck fracture is one of the most important management controversies. This study aims to evaluate and compare the short-term outcomes associated with the use of the Femoral Neck System (FNS), Multiple Cancellous Screws (MCS), and Dynamic Hip Screws (DHS) in treating femoral neck fractures in a young patient population. METHODS: From June 2018 to June 2021, a total of 120 surgeries for a primary femoral neck fracture were retrospectively analyzed. This review encompassed demographic details of the patients and the mechanisms behind the injuries. Key surgical parameters such as operation duration, intraoperative blood loss, fluoroscopy duration, and hospital stay were meticulously documented. The employed surgical technique was described. All patients were followed up at 6 weeks, 3 months, 6 months, and 12 months postoperatively. Avascular necrosis of the femoral head (AVN), nonunion, malreduction, implant failure or other complications were noted. The functional status at the last follow-up was assessed using the Harris functional scoring criteria. RESULTS: There were 90 males and 30 females, with a mean age of 40.4 years. As to patient characteristics, there were no significant differences between the three groups. DHS group showed longer operation time(52.15 ± 4.80 min), more blood loss(59.05 ± 5.87 ml) and longer time of hospitalization(7.6 ± 0.90 d) than FNS group (39.65 ± 2.84 min, 45.33 ± 9.63 ml and 4.87 ± 0.48 d) and MCS group (39.45 ± 3.10 min, 48.15 ± 7.88 ml and 5.04 ± 0.49 d) (p < 0.05). In addition, the time of fluoroscopy in FNS group (15.45 ± 3.67) was less than that in MCS group (26.3 ± 4.76) and DHS group (27.1 ± 5.67) (p < 0.05). The cost of FNS group(44.51 ± 2.99 thousand RMB) was significantly higher than the MCS and DHS groups. The FNS, MCS and DHS groups showed a similar mean length of femoral neck shortening (LFNS) and Harris score. The FNS, MCS and DHS groups showed a similar mean rate of AVN and internal fixation failure. CONCLUSIONS: Following successful fracture reduction, FNS, MCS, and DHS are effective for in the young femoral neck fractures. No difference was found in complications between the three groups. However, the reduced fluoroscopy time associated with FNS contributes to shorter operation durations. The adoption of minimally invasive techniques correlates with decreased blood loss and shorter hospital stays. Nevertheless, these advantages may be offset by the potential economic burden they impose.


Assuntos
Fraturas do Colo Femoral , Colo do Fêmur , Masculino , Feminino , Humanos , Adulto , Estudos Retrospectivos , Parafusos Ósseos , Fraturas do Colo Femoral/diagnóstico por imagem , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Resultado do Tratamento
12.
Sci Total Environ ; 914: 169901, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38184257

RESUMO

In recent years, dam failures have occurred frequently because of extreme weather, posing a significant threat to downstream residents. The establishment of emergency shelters is crucial for reducing casualties. The selection of suitable shelters depends on key information such as the number and distribution of affected people, and the effective capacity and accessibility of the shelters. However, previous studies on siting shelters did not fully consider population distribution differences at a finer scale. This limitation hinders the accuracy of estimating the number of affected people. In addition, most studies ignored the impact of extreme rainfall on the effective capacity and accessibility of shelters, leading to a low applicability of the shelter selection results. Therefore, in this study, land-use and land-cover change (LUCC) and nighttime lighting data were used to simulate population distribution and determine the number and distribution of affected people. Qualified candidate shelters were obtained based on screening criteria, and their effective capacity and accessibility information under different weather conditions were quantified. Considering factors such as population transfer efficiency, construction cost and shelter capacity constraints, a multi-objective siting model was established and solved using the non-dominated sorting genetic algorithm II (NSGA- II) to obtain the final siting scheme. The method was applied to the Dafangying Reservoir, and the results showed the following: (1) The overall mean relative error (MRE) of the population in the 35 downstream streets was 11.16 %, with good fitting accuracy. The simulation results truly reflect the population distribution. (2) Normal weather screening generated 352 qualified candidate shelters, whereas extreme rainfall weather screening generated 266 candidate shelters. (3) Based on the population distribution and weather factors, four scenarios were set up, with 63, 106, 73, and 131 shelters selected. These two factors have a significant impact on the selection of shelters and the allocation of evacuees, and should be considered in the event of a dam-failure floods.

13.
ACS Appl Mater Interfaces ; 16(3): 3520-3531, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38194411

RESUMO

Mg-Sn alloy thin films have garnered significant attention for their outstanding thermoelectric (TE) properties and cost-effective elemental composition, making them potential candidates for wearable energy harvesting devices. While previous studies have explored the properties of these thin films, limited research has been conducted to identify physical factors that can further enhance their performance. In this study, we present a novel approach utilizing a convenient electron beam coevaporation technique to fabricate Mg-Sn alloy thin films. Experimental results revealed that controlling the tin content in the Mg-Sn thin films at 38.9% led to the formation of a mixed-phase structure, comprising Mg2Sn and Mg9Sn5. This dual-phase structure exhibited a notable advantage in enhancing the TE performance. The presence of the Mg9Sn5 phase significantly increased the carrier concentration, while maintaining the original Seebeck coefficient and mobility, thereby improving the conductivity of Mg2Sn. Theoretical calculations indicated that the Mg9Sn5 phase displayed 1D-like characteristics, leading to a highly effective valley degeneracy and consequently a high power factor. Overall, this work introduces a promising approach to fabricate high-performance Mg-Sn alloy thin films through electron beam coevaporation, opening up possibilities for their application in wearable energy harvesting devices.

14.
J Thromb Thrombolysis ; 57(1): 89-100, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37605063

RESUMO

The role of direct oral anticoagulants (DOAC) in patients with atrial fibrillation (AF) and stage 4-5 chronic kidney disease (CKD) is controversial. Electronic medical records from 2012 to 2021 were retrieved for patients with AF and stage 4-5 CKD receiving oral anticoagulants. Patients were separated into those receiving DOACs (dabigatran, rivaroxaban, apixaban, or edoxaban) or vitamin K antagonists (VKA). Primary outcomes included ischemic stroke (IS), systemic thrombosis (SE), major bleeding, gastrointestinal bleeding, hemorrhagic stroke, acute myocardial infarction, cardiovascular death, and all-cause death. Renal outcomes included eGFR declines, creatinine doubling, progression to dialysis, and major adverse kidney events (MAKE). The primary analysis was until the end of follow up and the results at 1-year and 2-year of follow ups were also assessed. 2,382 patients (DOAC = 1,047, VKA = 1,335) between 2012 and 2021 with AF and stage 4-5 CKD were identified. The mean follow-up period was 2.3 ± 2.1 years in DOCAs and 2.6 ± 2.3 years in VKA respectively. At the end of follow up, the DOAC patients had significantly decreased SE (subdistribution hazard ratio [SHR] = 0.50, 95% confidence interval [CI] = 0.34-0.73), composite of IS/SE (SHR = 0.78, 95% CI = 0.62-0.98), major bleeding (HR = 0.77, 95% CI = 0.66-0.90), hemorrhagic stroke (HR = 0.52, 95% CI = 0.36-0.76), and composite of bleeding events (SHR = 0.80, 95% CI = 0.69-0.92) compared with VKA patients. The IS efficacy outcome revealed neutral between DOAC and VKA patients (HR = 1.05, 95% CI = 0.79-1.39). In addition, DOAC patients had significantly decreased rates of eGFR decline > 50% (SHR = 0.75, 95% CI = 0.64-0.87), creatinine doubling (SHR = 0.80, 95% CI = 0.67-0.95), and MAKE (SHR = 0.81, 95% CI = 0.71-0.93). In patients with AF and stage 4-5 CKD, use of DOAC was associated with decreased rates of a composite of ischemic stroke/systemic embolism, a composite of bleeding events, and renal events compared to VKA. Efficacy and safety benefits associated with apixaban at standard doses were consistent throughout follow-up.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral Hemorrágico , AVC Isquêmico , Falência Renal Crônica , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Acidente Vascular Cerebral Hemorrágico/induzido quimicamente , Acidente Vascular Cerebral Hemorrágico/complicações , Acidente Vascular Cerebral Hemorrágico/tratamento farmacológico , Estudos Retrospectivos , Creatinina , Anticoagulantes/efeitos adversos , Rivaroxabana/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Falência Renal Crônica/complicações , Rim , AVC Isquêmico/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Administração Oral
15.
Dement Geriatr Cogn Disord ; 53(1): 12-18, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38056437

RESUMO

INTRODUCTION: Stroke is common cerebrovascular disease in the elderly, which is characterized by neurological defects caused by cerebral vessels. Multiple studies have shown that miRNAs play important roles in stroke. In addition, a large number of evidence suggest that stroke increases the risk and severity of cognitive impairments. METHODS: miR-511-3p expression levels were detected by real-time PCR. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic value of miR-511-3p in distinguishing stroke patients from healthy controls and to assess risk of post-stroke cognitive impairment (PSCI) in stroke patients. Pearson correlation coefficient was used to determine the relationship between miR-511-3p expression level and Montreal Cognitive Assessment Scale (MoCA) scores. RESULTS: Serum miR-511-3p expression levels were decreased in stroke patients, and the decrease was more significant in PSCI patients. ROC curve results showed that miR-511-3p had high diagnostic accuracy in distinguishing healthy controls from stroke patients. Moreover, the expression level of miR-511-3p can be used as an independent predictor for the occurrence of PSCI and is positively correlated with MoCA scores of PSCI patients. CONCLUSION: miR-511-3p may be involved in the occurrence and development of stroke. In addition, miR-511-3p may be a novel biomarker for predicting PSCI occurred in stroke patients. These results may help improve the quality of prognosis of stroke.


Assuntos
Disfunção Cognitiva , MicroRNAs , Acidente Vascular Cerebral , Humanos , Idoso , Acidente Vascular Cerebral/complicações , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/genética , MicroRNAs/genética , Biomarcadores , Prognóstico
16.
Sensors (Basel) ; 23(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37960544

RESUMO

The upcoming Salinity Satellite, scheduled for launch in 2024, will feature the world's first phased array radar scatterometer. To validate its capability in measuring ocean surface backscatter coefficients, this paper conducts an in-depth analysis of the onboard verification flight test for the Salinity Satellite scatterometer. This paper provides a detailed introduction to the system design of the Salinity Satellite scatterometer, which utilizes phased array radar technology and digital beamforming techniques to achieve accurate measurements of sea surface scattering characteristics. The paper elaborates on the derivation of backscatter coefficients, system calibration, and phase amplitude correction for the phased array scatterometer. Furthermore, it describes the process of the onboard calibration flight test. By analyzing internal noise signals, onboard calibration signals, and external noise signals, the stability and reliability of the scatterometer system are validated. The experiment covers both land and ocean observations, with a particular focus on complex sea surface conditions in nearshore areas. Through the precise analysis of backscatter coefficients, the paper successfully distinguishes the different backscatter coefficient characteristics between ocean and land. The research results effectively demonstrate the feasibility of the Salinity Satellite scatterometer for measuring backscatter coefficients in a phased array configuration, as well as its outstanding performance in complex marine environments.

17.
Bioresour Technol ; 390: 129821, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37806360

RESUMO

Sponge iron (SI) is a promising material for nitrogen removal from wastewater. This study reveals the potential functions and mechanisms of SI-mediated multiple metabolic processes in the nitrogen removal of Anammox. The results showed that although the SI application prolonged the start-up time of the reactor, achieved efficient and stable nitrogen removal after a successful start-up. The total nitrogen removal efficiency of the SI-Anammox system (92.62%) was 13.30% higher than that of R0 without SI (79.32%). The increase in nitrogen removal performance was accompanied by an increase in SAA and EPS content. Further microbial analysis showed significant enrichment of functional microorganisms, such as Candidatus_Brocadia, Nitrosomonas, Ellin6067, and Nitrospira. Multi-omics evidence suggests that efficient nitrogen removal is ultimately attributable to the enhancement of the specific key Fe- and N-functional genes in Anammox.


Assuntos
Compostos de Amônio , Águas Residuárias , Anaerobiose , Oxirredução , Compostos de Amônio/metabolismo , Ferro , Reatores Biológicos , Nitrogênio/metabolismo , Desnitrificação , Esgotos
18.
Int J Biol Macromol ; 253(Pt 8): 127495, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37858642

RESUMO

Developing biocompatible and antibacterial materials with biodegradable polymers is an ideal strategy to improve public health problems and plastic pollution simultaneously. In the present study, novel biocompatible and antibacterial poly (L-lactic acid) (PLLA, coded as P)/TEMPO-oxidized cellulose nanofiber (TOCNF, coded as T)­silver nanoparticle (AgNP, coded as A) films were first developed. The core/shell PT Pickering emulsion was prepared by sonication treatment. The TOCNF shells with -COO-Na+ groups (∼1.5 mmol/g cellulose) were used as the support to in situ synthesize and immobilize AgNPs on the PT emulsion droplets. Silver nitrate (AgNO3) (1.5, 3.0, 4.5, and 6.0 mmol/g cellulose) was added to the PT emulsions. Then, ion-exchange reaction and hydrothermal reduction were conducted to form PTA (PTA1-PTA4) emulsions. After centrifugation to remove the excess Ag+, filtration, oven-drying, and hot-pressing, the PTA composite films were successfully prepared. The PTA3 film contained AgNPs 12.4 ± 2.8 nm in diameter and exhibited the highest antibacterial activities against the E. coli (85.2%) and S. aureus (80.1%) at 37 °C, where the initial bacterial suspension concentrations were approximately 2 × 108 CFU mL-1. Therefore, the biocompatible and antibacterial PTA3 film is a promising candidate for biomedical applications, in particular as an antibacterial bioactive packaging material.


Assuntos
Nanopartículas Metálicas , Nanofibras , Celulose , Emulsões , Escherichia coli , Staphylococcus aureus , Prata , Antibacterianos/farmacologia
19.
Biochem Pharmacol ; 217: 115817, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37757917

RESUMO

Osteoporosis, characterized by over-production and activation of osteoclasts, has become a major health problem especially in elderly women. In our study, we first tested the effect of Caudatin (Cau) in osteoclastogenesis, which is separated from Cynanchum auriculatum as a species of C-21 steroidal glyosides. The results indicated that Cau suppressed osteoclastogenesis in a time- and dose-dependent manner in vitro. Mechanistically, Cau was identified to inhibit NF-κB signaling pathway via modulation of KIF11-mediated mTORC1 activity. In vivo, by establishing an ovariectomized (OVX) mouse model to mimic osteoporosis, we confirmed that Cau treatment prevented OVX-induced bone loss in mice. In conclusion, we demonstrated that Cau inhibited NF-κB signaling pathway via modulation of KIF11-mediated mTORC1 activity to suppress osteoclast differentiation in vitro as well as OVX-induced bone loss in vivo. This provides the possibility of a novel prospective drug for osteoporosis remedies.


Assuntos
Reabsorção Óssea , Osteoporose , Animais , Camundongos , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/prevenção & controle , Reabsorção Óssea/metabolismo , Diferenciação Celular , Cinesinas/metabolismo , NF-kappa B/metabolismo , Osteoclastos , Osteogênese , Osteoporose/tratamento farmacológico , Osteoporose/prevenção & controle , Osteoporose/metabolismo , Ovariectomia , Ligante RANK/farmacologia , Transdução de Sinais , Alvo Mecanístico do Complexo 1 de Rapamicina
20.
Exp Gerontol ; 178: 112195, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37121335

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disease with high incidence in the elderly population. MicroRNAs have been reported to abnormally expressed in patients with AD. In this study, we investigated the role of inflammation-related miR-511-3p in AD patients and AD cell models. METHOD: The level of miR-511-3p was quantified by Real-Time PCR. The diagnostic value was evaluated by receiver operating characteristic curve (ROC) analysis. The correlation between miR-511-3p expression levels and ini-mental state examination (MMSE) scores, Montreal Cognitive Assessment (MoCA) scores and inflammatory factors was analyzed. The concentrations of IL-1ß, IL-6 and TNF-α were measured by Enzyme-Linked Immunosorbent Assay (ELISA) in AD cell model and serum from AD patients. RESULT: Serum miR-511-3p expression was decreased in AD patients and correlated with MMSE score, MoCA score and inflammatory response. MiR-511-3p mimics significantly reversed the effects of Aß 1-40 on inflammation in AD cells. ROC curve results showed that miR-511-3p had high diagnostic accuracy in distinguishing normal controls from AD patients. CONCLUSION: Our results show that miR-511-3p is down-regulated in AD patients and has high diagnostic value. MiR-511-3p may participate in the development of AD by regulating the levels of neuroinflammatory factors in AD cells. MiR-511-3p may provide a new perspective for the prevention and pathogenesis of AD.


Assuntos
Doença de Alzheimer , MicroRNAs , Doenças Neurodegenerativas , Humanos , Idoso , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Sobrevivência Celular , MicroRNAs/metabolismo , Biomarcadores , Inflamação
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