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1.
Phys Chem Chem Phys ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39139147

RESUMEN

The external electric field has emerged as a powerful tool for building molecular switches with excellent properties. In this work, we investigate the impact of an external electric field on the transition between lithium salt and electride-like molecule conformations in Li@corannulene. Remarkably, the distance between the Li atom and the corannulene bottom displays a sharp increase under the influence of an external electric field strength of F-z = 110 × 10-4 a.u. As the external electric field strength increases, the Li atom brings about different directions of charge transfer (CT). The natural population analysis (NPA) charge and the molecular electrostatic potential (ESP) results show that the intermolecular CT occurs from the Li atom to the corannulene with the F-z ranging from 0 to 100 × 10-4 a.u. Interestingly, when the external electric field reaches F-z = 110 × 10-4 a.u., the CT is oriented from the corannulene to the Li atom. Moreover, electron localization function (ELF) basins are presented under an F-z of 110 × 10-4 a.u., which indicates that Li@corannulene exhibits electride-like (e-⋯[Li@corannulene]+) molecules and lithiation salt (Li+[corannulene]-) under an F-z of 0 to 100 × 10-4 a.u. Significantly, the differences in charge transfer also contribute to a significant improvement in hyperpolarizabilities (ßtot) during the conformation transition from lithiation salt (Li+[corannulene]-) to electride-like (e-⋯[Li@corannulene]+) molecules. This study explores the potential of Li@corannulene as a promising second-order NLO material, and the external electric field provides an efficient strategy for designing and developing NLO switching devices.

2.
Chem Sci ; 15(31): 12442-12450, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39118600

RESUMEN

C-H Functionalization of pyridines is an efficient strategy to access pyridine derivatives occurring in pharmaceuticals, agrochemicals, and materials. Nucleophilic additions to pyridiniums via both ionic and radical species have proven particularly useful. However, these reactions suffer from poor regioselectivity. By identifying an enzyme-mimic pocket-type urea activation reagent, we report a general platform for pyridine C-4 functionalization. Both ionic and radical nucleophiles can be incorporated to achieve the alkylation and arylation. Notably, the highly regioselective C-4 radical arylation is disclosed for the first time. The broad scope of nucleophiles and pyridines renders this platform applicable to the late-stage functionalization of drug-like molecules and the preparation of complex biologically important molecules.

3.
Int J Biol Sci ; 20(10): 3784-3801, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39113709

RESUMEN

Ubiquitination, a prevalent and highly dynamic reversible post-translational modification, is tightly regulated by the deubiquitinating enzymes (DUBs) superfamily. Among them, OTU Domain-Containing Ubiquitin Aldehyde-Binding Protein 1 (OTUB1) stands out as a critical member of the OTU deubiquitinating family, playing a pivotal role as a tumor regulator across various cancers. However, its specific involvement in BLCA (BLCA) and its clinical significance have remained ambiguous. This study aimed to elucidate the biofunctions of OTUB1 in BLCA and its implications for clinical prognosis. Our investigation revealed heightened OTUB1 expression in BLCA, correlating with unfavorable clinical outcomes. Through in vivo and in vitro experiments, we demonstrated that increased OTUB1 levels promote BLCA tumorigenesis and progression, along with conferring resistance to cisplatin treatment. Notably, we established a comprehensive network involving OTUB1, ß-catenin, necroptosis, and BLCA, delineating their regulatory interplay. Mechanistically, we uncovered that OTUB1 exerts its influence by deubiquitinating and stabilizing ß-catenin, leading to its nuclear translocation. Subsequently, nuclear ß-catenin enhances the transcriptional activity of c-myc and cyclin D1 while suppressing the expression of RIPK3 and MLKL, thereby fostering BLCA progression and cisplatin resistance. Importantly, our clinical data suggest that the OTUB1/ß-catenin/RIPK3/MLKL axis holds promise as a potential biomarker for BLCA.


Asunto(s)
Cisteína Endopeptidasas , Transducción de Señal , beta Catenina , Humanos , beta Catenina/metabolismo , Animales , Cisteína Endopeptidasas/metabolismo , Cisteína Endopeptidasas/genética , Ratones , Enzimas Desubicuitinizantes/metabolismo , Línea Celular Tumoral , Ratones Desnudos , Ubiquitinación , Cisplatino/farmacología , Cisplatino/uso terapéutico
4.
Sci Rep ; 14(1): 18781, 2024 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138326

RESUMEN

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight in rice. Polyhydroxyalkanoates (PHAs) consitute a diverse group of biopolyesters synthesized by bacteria under nutrient-limited conditions. The phaC gene is important for PHA polymerization. We investigated the effects of phaC gene mutagensis in Xoo strain PXO99A. The phaC gene knock-out mutant exhibited reduced swarming ability relative to that of the wild-type. Under conditions where glucose was the sole sugar source, extracellular polysaccharide (EPS) production by ΔphaC declined by 44.8%. ΔphaC showed weak hypersensitive response (HR) induction in the leaves of non-host Nicotiana tabacum, concomitant with downregulation of hpa1 gene expression. When inoculated in rice leaves by the leaf-clipping method, ΔphaC displayed reduced virulence in terms of lesion length compared with the wild-type strain. The complemented strain showed no significant difference from the wild-type strain, suggesting that the deletion of phaC in Xoo induces significant alterations in various physiological and biological processes. These include bacterial swarming ability, EPS production, transcription of hrp genes, and glucose metabolism. These changes are intricately linked to the energy utilization and virulence of Xoo during plant infection. These findings revealed involvement of phaC in Xoo is in the maintaining carbon metabolism by functioning in the PHA metabolic pathway.


Asunto(s)
Proteínas Bacterianas , Carbono , Oryza , Enfermedades de las Plantas , Polisacáridos Bacterianos , Xanthomonas , Xanthomonas/patogenicidad , Xanthomonas/genética , Xanthomonas/metabolismo , Oryza/microbiología , Carbono/metabolismo , Enfermedades de las Plantas/microbiología , Virulencia/genética , Polisacáridos Bacterianos/metabolismo , Polisacáridos Bacterianos/biosíntesis , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Mutación , Regulación Bacteriana de la Expresión Génica , Polihidroxialcanoatos/biosíntesis , Polihidroxialcanoatos/metabolismo , Nicotiana/microbiología , Hojas de la Planta/microbiología
5.
Front Plant Sci ; 15: 1403202, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39049860

RESUMEN

Background: Pepper veinal mottle virus (PVMV) belongs to the genus Potyvirus within the family Potyviridae and is a major threat to pepper production, causing reduction in yield and fruit quality; however, efficient pesticides and chemical treatments for plant protection against viral infections are lacking. Hence, there is a critical need to discover highly active and environment-friendly antiviral agents derived from natural sources. Bacillus spp. are widely utilized as biocontrol agents to manage fungal, bacterial, and viral plant diseases. Particularly, Bacillus velezensis HN-2 exhibits a strong antibiotic activity against plant pathogens and can also induce plant resistance. Methods: The experimental subjects employed in this study were Bacillus velezensis HN-2, benzothiadiazole, and dufulin, aiming to evaluate their impact on antioxidant activity, levels of reactive oxygen species, activity of defense enzymes, and expression of defense-related genes in Nicotiana benthamiana. Furthermore, the colonization ability of Bacillus velezensis HN-2 in Capsicum chinense was investigated. Results: The results of bioassays revealed the robust colonization capability of Bacillus velezensis HN-2, particularly in intercellular spaces, leading to delayed infection and enhanced protection against PVMV through multiple plant defense mechanisms, thereby promoting plant growth. Furthermore, Bacillus velezensis HN-2 increased the activities of antioxidant enzymes, thereby mitigating the PVMV-induced ROS production in Nicotiana benthamiana. Moreover, the application of Bacillus velezensis HN-2 at 5 dpi significantly increased the expression of JA-responsive genes, whereas the expression of salicylic acid-responsive genes remained unchanged, implying the activation of the JA signaling pathway as a crucial mechanism underlying Bacillus velezensis HN-2-induced anti-PVMV activity. Immunoblot analysis revealed that HN-2 treatment delayed PVMV infection at 15 dpi, further highlighting its role in inducing plant resistance and promoting growth and development. Conclusions: These findings underscore the potential of Bacillus velezensis HN-2 for field application in managing viral plant diseases effectively.

6.
Nanomaterials (Basel) ; 14(14)2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39057875

RESUMEN

A phase-field model for the precipitation of Fe-Cr-Al alloy is established incorporating grain boundary (GB) effects and irradiation-accelerated diffusion. The radiation source and grain boundary effect are incorporated to broaden the applicability of the Fe-Cr-Al precipitated phase-field model. The model is firstly employed to simulate the precipitation of the Cr-rich α' phase in a single-crystal alloy. The precipitation rate and the size distribution of the precipitated phase were analyzed. Subsequently, the model is utilized to simulate segregation at GBs in a double-crystal system, analyzing the enrichment of Cr and depletion of Al near these boundaries. The simulation results are consistent with experimental observations reported in the references. Finally, the model is applied to simulate the precipitation in a polycrystalline Fe-Cr-Al system. The simulated results revealed that the presence of GBs induces the formation of localized regions with enhanced Cr and Al content as well as depleted zones adjacent to these boundaries. GBs also diminish both the quantity and precipitation rate of the formed phase within the grains.

7.
Trials ; 25(1): 511, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39075524

RESUMEN

BACKGROUND: Postoperative respiratory adverse events are the most common perioperative complications in pediatric anesthesia, particularly prevalent in children undergoing tonsillectomy and adenoidectomy, with an incidence rate as high as 50%. The choice of anesthetic induction regimen directly influences the incidence of respiratory adverse events during the induction period. However, this effect seems to have minimal impact on postoperative outcomes. The occurrence rate of postoperative respiratory adverse events is likely more closely associated with the anesthetic maintenance phase, yet this relationship remains uncertain at present. METHODS: The objective of this study was to assess the impact of different anesthetic maintenance regimens on postoperative respiratory adverse events in pediatric patients undergoing tonsillectomy and adenoidectomy. The AmPRAEC study is a multicenter, randomized, double-blind controlled trial. A total of 717 pediatric patients were recruited from 12 medical centers and randomly assigned to three groups: group A (intravenous maintenance group, receiving propofol infusion); group B (intravenous-inhalational combination group, maintained with 1% sevoflurane combined with propofol); and group C (inhalational maintenance group, maintained with 2-3% sevoflurane inhalation). The primary outcome measure was the incidence rate of postoperative respiratory adverse events. DISCUSSION: This clinical trial aims to elucidate the impact of various anesthetic maintenance regimens on postoperative respiratory adverse events in pediatric patients. The outcomes of this study are anticipated to facilitate anesthesiologists in devising more comprehensive perioperative management strategies, enhancing comfort, and improving the clinical outcomes for this patient population. TRIAL REGISTRATION: Chinese Clinical Trial Registry ( http://www.chictr.org.cn ) ChiCTR2300074803. Registered on August 16, 2023.


Asunto(s)
Adenoidectomía , Complicaciones Posoperatorias , Propofol , Ensayos Clínicos Controlados Aleatorios como Asunto , Sevoflurano , Tonsilectomía , Humanos , Tonsilectomía/efectos adversos , Adenoidectomía/efectos adversos , Método Doble Ciego , Niño , Sevoflurano/administración & dosificación , Sevoflurano/efectos adversos , Preescolar , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Propofol/administración & dosificación , Propofol/efectos adversos , Masculino , Femenino , Estudios Multicéntricos como Asunto , Anestésicos Intravenosos/administración & dosificación , Anestésicos Intravenosos/efectos adversos , Resultado del Tratamiento , Anestésicos por Inhalación/efectos adversos , Anestésicos por Inhalación/administración & dosificación , China/epidemiología , Factores de Tiempo , Adolescente
8.
ACS Appl Mater Interfaces ; 16(28): 36628-36636, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38954707

RESUMEN

Real-time detection of harmful gases at room temperature has become a serious problem in public health and environmental monitoring. Two-dimensional materials with semiconductor properties BiOCl is a promising gas-sensitive material due to its large specific surface area and adjustable band gap as well as outstanding safety characteristics. However, limited by the weak gas adsorption sites and sluggish charge-transfer ability, the performance of BiOCl could not be fully exploited. Oxygen vacancy (Vo) engineering can introduce lattice defects, thereby significantly increasing the local charge density and enhancing the adsorption of gases, which is an effective strategy to enhance the gas-sensing performance. In this work, we composite BiOCl with a vacancy (Vo-BiOCl) and reduced graphene oxide (rGO) to construct a Vo-BiOCl/rGO heterostructure with enhanced gas adsorption sites. Experimental and theoretical calculations show that Vo can enhance the adsorption of gases and the introduction of rGO forms a high-quality heterostructure with BiOCl, which can effectively reduce the band gap of BiOCl and promote electron transfer, thereby improving the sensitivity of the sensor. Benefiting from above, Vo-BiOCl/rGO achieves the ability to detect low concentrations of NO2/NH3 at room temperature, with high sensitivity (55% at 1 ppm of NO2 and -28% at 1 ppm of NH3), fast response time (40 s at 1 ppm of NO2 and 2 s at 1 ppm of NH3), good stability (over 150 days), and fully recoverable gas sensitivity.

9.
Angew Chem Int Ed Engl ; : e202411014, 2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39034426

RESUMEN

A novel Ir-Mn dual-atom electrocatalyst is synthesized by a facile ion-exchange method by incorporating Ir in SrMnO3, which yields an extremely high activity and stability for the oxygen evolution reaction (OER). The ion exchange process occurs in a self-limitation way, which favors the formation of Ir-Mn dual-atom in the IrMnO9 unit. The incorporation of Ir modulates the electronic structure of both Ir and Mn, thereby resulting in a shorter distance of the Ir-Mn dual-atom (2.41 Å) than the Mn-Mn dual-atom (2.49 Å). The modulated Ir-Mn dual-atom enables the same spin direction O (↑) of the adsorbed *O intermediates, thus facilitating the direct coupling of the two adsorbed *O intermediates to release O2 via the oxygen-oxygen radical coupling mechanism. Electrochemical tests reveal that the Ir-SrMnO3 exhibits a superior OER's activity with a low overpotential of 207 mV at 10 mA cm-2 and achieves a mass specific activity of 1100 A gIr-1 at 1.5 V. The proton-exchange-membrane water electrolyzer with the Ir-SrMnO3 catalyst exhibits a low electrolysis voltage of 1.63 V at 1.0 A cm-2 and a stable 2000-h operation with a decay of only 15 µV h-1 at 0.5 A cm-2.

10.
Adv Mater ; 36(31): e2403659, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38843445

RESUMEN

On-chip integration of 2D materials with unique structures and properties endow integrated devices with new functionalities and improved performance. With high flexibility in ways to modify its properties and compatibility with integrated platforms, graphene oxide (GO) is an exceptionally attractive 2D material for hybrid integrated photonic chips. Here, by harnessing unique property changes induced by photothermal effects in 2D GO films, novel functionalities beyond the capability of photonic integrated circuits are demonstrated. These include all-optical control and tuning, optical power limiting, and nonreciprocal light transmission. The 2D layered GO films are integrated onto photonic chips with precise control of their thickness and size. Benefitting from the broadband optical response of 2D GO films, all three functionalities feature a very wide operational optical bandwidth. By fitting the experimental results with theory, the changes in GO film properties induced by the photothermal effects are analyzed, revealing interesting insights about the physics of 2D GO films. These results highlight the versatility of 2D GO films in implementing new functions for integrated photonic devices for a wide range of applications.

11.
Nanomaterials (Basel) ; 14(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38921902

RESUMEN

The corrosion behavior of 20G and TP347H materials was investigated in molten LiCl-NaCl-KCl salt. The corrosion rates of these materials in molten chloride salt are high and are strongly affected by the alloying surface oxide formation. The 20G shows uniform surface corrosion with almost no protective oxide formation on the surface. In contrast, the austenitic steel TP347H exhibits better corrosion resistance in molten chloride salts due to its high Cr content. Owing to the highly corrosive nature of molten chloride salts, the Cl- in molten salt could react with oxides and alloy, inducing intergranular corrosion of austenitic steel in molten chloride salt environments.

12.
Small Methods ; : e2400411, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850177

RESUMEN

Sn-based materials with high capacity showcase great potential for next-generation lithium-ion batteries (LIBs). Yet, the large volume change and limited ion/electron transfer efficiency of Sn-based materials upon operation significantly compromises the battery performance. In this study, a unique 3D copper-nickel nanoporous column array current collector is rationally developed via a facile template-free galvanostatic electrodeposition method, followed by electrodepositing SnS active material onto it (denoted as 3D SnS@CNCA). Excitingly, the morphology of the 3D SnS@CNCA electrode perfectly inherited the nanoporous column array structure of the 3D current collector, which not only endows the electrode with a large specific surface area to provide more active sites and sufficient ion/electron transport pathways, but also effectively alleviates the volume expansion of SnS upon repeated charge-discharge cycles. Therefore, the binder-free 3D SnS@CNCA electrode showcases a significantly enhanced Li storage performance, showing a high initial reversible capacity of 1019.7 mAh g-1 with noteworthy cycling stability (a capacity retention rate of 89.4% after 200 cycles). Moreover, the designed electrode also manifests high rate performance with a high capacity of 570.6 mAh g-1 at 4 A g-1. This work provides a novel design idea for the preparation of high-performance electrodes beyond LIBs.

13.
J Phys Chem Lett ; 15(26): 6835-6840, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38917057

RESUMEN

Organic-inorganic hybrid ternary copper halides offer a broader spectrum of structural possibilities for finely tuning their optoelectronic properties. Herein, we demonstrate for the first time the potential of [N(C2H5)4]2[Cu2Br4], a zero-dimensional hybrid copper halide [(TEA)2Cu2Br4], for ultraviolet (UV) photodetection. A self-powered, visible-blind UV photodetector based on a (TEA)2Cu2Br4/GaN heterojunction architecture is developed, exhibiting a high responsivity, a high detectivity, and fast response speeds. The device demonstrates exceptional stability against environmental oxygen/moisture, heat, and UV light illumination, surpassing the stability of reported copper-based UV photodetectors. Our work highlights the significant potential of (TEA)2Cu2Br4 as a lead-free, stable, and efficient material for next-generation UV photodetection technology.

14.
Int J Biol Macromol ; 273(Pt 2): 133191, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38880455

RESUMEN

Abdominal hernia mesh is a common product which is used for prevention of abdominal adhesion and repairing abdominal wall defect. Currently, designing and preparing a novel bio-mesh material with prevention of adhesion, promoting repair and good biocompatibility simultaneously remain a great bottleneck. In this study, a novel siloxane-modified bacterial cellulose (BC) was designed and fabricated by chemical vapor deposition silylation, then the effects of different alkyl chains length of siloxane on surface properties and cell behaviors were explored. The effect of preventing of abdominal adhesion and repairing abdominal wall defect in rats with the siloxane-modified BC was evaluated. As the grafted alkyl chains become longer, the surface of the siloxane-modified BC can be transformed from super hydrophilic to hydrophobic. In vivo results showed that BC-C16 had good long-term anti-adhesion effect, good tissue adaptability and histocompatibility, which is expected to be used as a new anti-adhesion hernia repair material in clinic.


Asunto(s)
Celulosa , Animales , Celulosa/química , Celulosa/farmacología , Ratas , Adherencias Tisulares/prevención & control , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Masculino , Pared Abdominal/cirugía , Pared Abdominal/patología , Interacciones Hidrofóbicas e Hidrofílicas , Ratones , Propiedades de Superficie , Hernia Abdominal/prevención & control , Mallas Quirúrgicas , Ratas Sprague-Dawley
15.
Chemistry ; 30(41): e202401619, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38773843

RESUMEN

Organic molecules with light-modifiable reactivity are important in many fields because they can serve as the "switch" for light to trigger chemical processes. Herein, we disclose a new type of stable non-twisted amides, the reactivity of which can be turned on by light as acyl transfer reagents. Upon photo-activation, these amides react with various nucleophiles including amines, phenols, hydroxide, thiols, boronic acids, and alkynes either under metal-free or metal-catalysis conditions. This reactivity hinges on the design and synthesis of a photo-activatable reagent (7-nitro-5,6-dihydrophenanthridine), which undergoes self-aromatization enabled by an internal oxidant under light. This masked acyl donor group is anticipated to be useful in scenarios where light is preferred to trigger a chemical process.

16.
Int J Ophthalmol ; 17(3): 551-557, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38721499

RESUMEN

AIM: To introduce the macular hole (MH) hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH. METHODS: This retrospective observational case series comprised 16 consecutive patients (17 eyes) diagnosed with MH. Inclusion criteria involved a hole aperture diameter larger than 600 µm or the presence of an unclosed MH larger than 600 µm following the previous vitrectomy. Standard MH repair procedures were administered in all cases, involving the manipulation and aspiration of the hole margin through the application of water flow with a soft-tip flute needle. A comprehensive assessment was conducted for each case before and after surgery, and optical coherence tomography (OCT) images were captured at every follow-up point. RESULTS: The mean preoperative aperture diameter was 747±156 µm (range 611-1180 µm), with a mean base diameter of 1390±435 µm (range 578-2220 µm). Following surgery, all cases achieved complete anatomical closure of MH, with 13 cases (76.5%) exhibiting type 1 closure and 4 cases (23.5%) demonstrating type 2 closure. No significant differences were observed in the preoperative OCT variables between the two closure types. Eyes with type 1 closure showed a significantly improved visual acuity (0.70±0.10, range 0.50-0.80) compared to those with type 2 closure (0.90±0.12, range 0.80-1.00, P=0.014). CONCLUSION: The MH hydromassage technique demonstrates promising results, achieving acceptable closure rates in cases of large or persistent MH. This technique may serve as an effective adjunctive maneuver during challenging MH surgery.

17.
Materials (Basel) ; 17(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38730927

RESUMEN

A new approach is proposed that identifies three different zones of the Si-rich network structure (the cellular structure) in laser powder bed fused (LPBF) AlSi10Mg alloy, based on the variation in morphology, grain growth transition, and melt pool solidification conditions. The three identified zones are denoted in the present work as the liquid solidification zone (LSZ), the mushy solidification zone (MSZ), and the heat affected zone (HAZ). The LSZ is the result of liquid-solid transformation, showing small planar growth at the boundary and large cellular growth in the center, while the MSZ is related to a semisolid reaction, and the HAZ arises from a short-time aging process. The boundary between the LSZ and MSZ is identified by the change of grain growth direction and the Si-rich network advancing direction. The boundary between MSZ and HAZ is identified by the start of the breakdown of the Si-rich network. In addition, it is found that the fracture is generated in and propagates along the HAZ during tensile tests.

18.
Micromachines (Basel) ; 15(5)2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38793210

RESUMEN

Improving measurement accuracy is the core issue with surface acoustic wave (SAW) micro-force sensors. An electrode transducer can stimulate not only the SAW but also the bulk acoustic wave (BAW). A portion of the BAW can be picked up by the receiving transducer, leading to an unwanted or spurious signal. This can harm the device's frequency response characteristics, thereby potentially reducing the precision of the micro-force sensor's measurements. This paper examines the influence of anisotropy on wave propagation, and it also performs a phase-matching analysis between interdigital transducers (IDTs) and bulk waves. Two solutions are shown to reduce the influence of BAW for SAW micro sensors, which are arranged with acoustic absorbers at the ends of the substrate and in grooving in the piezoelectric substrate. Three different types of sensors were manufactured, and the test results showed that the sidelobes of the SAW micro-force sensor could be effectively inhibited (3.32 dB), thereby enhancing the sensitivity and performance of sensor detection. The SAW micro-force sensor manufactured using the new process was tested and the following results were obtained: the center frequency was 59.83 MHz, the fractional bandwidth was 1.33%, the range was 0-1000 mN, the linearity was 1.02%, the hysteresis was 0.59%, the repeatability was 1.11%, and the accuracy was 1.34%.

19.
Orphanet J Rare Dis ; 19(1): 218, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802922

RESUMEN

BACKGROUND: Microtia is reported to be one of the most common congenital craniofacial malformations. Due to the complex etiology and the ethical barrier of embryonic study, the precise mechanisms of microtia remain unclear. Here we report a rare case of microtia with costal chondrodysplasia based on bioinformatics analysis and further verifications on other sporadic microtia patients. RESULTS: One hundred fourteen deleterious insert and deletion (InDel) and 646 deleterious SNPs were screened out by WES, candidate genes were ranked in descending order according to their relative impact with microtia. Label-free proteomic analysis showed that proteins significantly different between the groups were related with oxidative stress and energy metabolism. By real-time PCR and immunohistochemistry, we further verified the candidate genes between other sporadic microtia and normal ear chondrocytes, which showed threonine aspartase, cadherin-13, aldolase B and adiponectin were significantly upregulated in mRNA levels but were significantly lower in protein levels. ROS detection and mitochondrial membrane potential (∆ Ψ m) detection proved that oxidative stress exists in microtia chondrocytes. CONCLUSIONS: Our results not only spot new candidate genes by WES and label-free proteomics, but also speculate for the first time that metabolism and oxidative stress may disturb cartilage development and this might become therapeutic targets and potential biomarkers with clinical usefulness in the future.


Asunto(s)
Microtia Congénita , Estrés Oxidativo , Humanos , Microtia Congénita/genética , Microtia Congénita/metabolismo , Estrés Oxidativo/genética , Proteómica , Masculino , Femenino , Condrocitos/metabolismo , Condrocitos/patología , Multiómica
20.
ACS Appl Mater Interfaces ; 16(20): 26674-26684, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38717387

RESUMEN

Flexible pressure sensors have attracted great interest as they play an important role in various fields such as health monitoring and human-machine interactions. The design of the pressure sensors still faces challenges in achieving a high sensitivity for a wide sensing range, and the interference of water restricts the applications of the sensors. Herein, we developed a graphene-polydimethylsiloxane film combining a hierarchical surface with nanowrinkles on it and a hollow structure. The microstructure design of the composite can be facilely controlled to improve the sensing and hydrophobic performance by tailoring the microsphere building units. Attributed to the irregular surface and hollow structure of the sensing layer, the optimized sensor exhibits a superior sensitivity of 1085 kPa-1 in a 50 kPa linear range. For practical applications, the nanowrinkles on the surface of the microspheres and the polymer coating endow the composite with waterproof properties. Inspired by the dual receptors of the skin, two designed microstructured films can simply integrate into one with double-sided microstructures. The sensing performance and the water-repellence property allow the sensor to detect physiological signals under both ambient and underwater conditions. Furthermore, underwater stimuli detection and communication are demonstrated. This method of fabricating a flexible sensor shows great potential in wearable and robotic fields.

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