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1.
Plant J ; 119(2): 814-827, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38739690

RESUMO

Several dwarf and semi-dwarf genes have been identified in barley. However, only a limited number have been effectively utilized in breeding programs to cultivate lodging resistant varieties. This is due to the common association of dwarf and semi-dwarf traits with negative effects on malt quality. In this study, we employed gene editing to generate three new haplotypes of sdw1/denso candidate gene gibberellin (GA) 20-oxidase2 (GA20ox2). These haplotypes induced a dwarfing phenotype and enhancing yield potential, and promoting seed dormancy, thereby reducing pre-harvest sprouting. Moreover, ß-amylase activity in the grains of the mutant lines was significantly increased, which is beneficial for malt quality. The haplotype analysis revealed significant genetic divergence of this gene during barley domestication and selection. A novel allele (sdw1.ZU9), containing a 96-bp fragment in the promoter region of HvGA20ox2, was discovered and primarily observed in East Asian and Russian barley varieties. The 96-bp fragment was associated with lower gene expression, leading to lower plant height but higher germination rate. In conclusion, HvGA20ox2 can be potentially used to develop semi-dwarf barley cultivars with high yield and improved malt quality.

2.
Int Arch Allergy Immunol ; : 1-9, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38763133

RESUMO

INTRODUCTION: Although microRNA (miR)-150-5p participates in the progression of renal fibrosis, its mechanism of action remains elusive. METHODS: A mouse model of unilateral ureteral obstruction was used. The in vitro renal fibrosis model was established by stimulating human kidney 2 (HK-2) cells with transforming growth factor beta 1 (TGF-ß1). The expression profiles of miR-150-5p, zinc finger E-box binding homeobox 1 (ZEB1), and other fibrosis- and epithelial-mesenchymal transition (EMT)-linked proteins were determined using Western blot and quantitative reverse transcription polymerase chain reaction. The relationship between miR-150-5p and ZEB1 in HK-2 cells was confirmed by a dual-luciferase reporter assay. RESULTS: Both in vivo and in vitro renal fibrosis models revealed reduced miR-150-5p expression and elevated ZEB1 level. A significant decrease in E-cadherin levels, as well as increases in alpha smooth muscle actin (α-SMA) and collagen type I (Col-I) levels, was seen in TGF-ß1-treated HK-2 cells. The overexpression of miR-150-5p ameliorated TGF-ß1-mediated fibrosis and EMT. Notably, miR-150-5p acts by directly targeting ZEB1. A significant reversal of the inhibitory impact of miR-150-5p on TGF-ß1-mediated fibrosis and EMT in HK-2 cells was observed upon ZEB1 overexpression. CONCLUSION: MiR-150-5p suppresses TGF-ß1-induced fibrosis and EMT by targeting ZEB1 in HK-2 cells, providing helpful insights into the therapeutic intervention of renal fibrosis.

3.
Sensors (Basel) ; 24(15)2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39124014

RESUMO

Given the challenges associated with the low accuracy, complexity of the equipment, and poor interference resistance observed in current wireless multipath channel measurements, this study introduces a novel algorithm called KFSC-WRELAX. This algorithm integrates techniques involving pseudorandom noise (PN) sequences, Kalman filtering (KF), sliding correlation, and weighted Fourier transform combined with the RELAXation (WRELAX) algorithm. An m-sequence is employed as the probing sequence for channel detection. The effectiveness of the KFSC-WRELAX algorithm is demonstrated through both simulation experiments and corridor testing, showing that it can accurately determine the delays in various paths with robust performance at a signal-to-noise ratio (SNR) of -5 dB or higher.

4.
Nano Lett ; 23(11): 4778-4784, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37252749

RESUMO

Ferrimagnets are considered an excellent spintronic material candidate which combines ultrafast magnetic dynamics and straightforward electrical detectability. However, efficient routes toward magneto-ionic control of ferrimagnetic order remain elusive. In this study, a solid-state oxygen gating device was designed to control the magnetic properties of the ferrimagnetic CoTb alloy. Experimental results show that applying a small voltage can irreversibly tune a Tb-dominant device to a stable Co-dominant state and decrease the magnetization compensation temperature by 130 K. In addition, a reversible voltage control of the magnetization axis between out-of-plane and in-plane states is observed, which indicates that the migrated oxygen ions can bond to both Tb and Co sublattices. First-principles calculations indicate that voltage can dynamically control the flow-in and flow-out of oxygen ions that bond to the Co sublattice. Our work provides an effective means to manipulate ferrimagnetic order and contributes to the development of ultra-low-power spintronic devices.

5.
Nano Lett ; 23(14): 6378-6385, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37418477

RESUMO

Unidirectional magnetoresistance (UMR) has been intensively studied in ferromagnetic systems, which is mainly induced by spin-dependent and spin-flip electron scattering. Yet, UMR in antiferromagnetic (AFM) systems has not been fully understood to date. In this work, we reported UMR in a YFeO3/Pt heterostructure where YFeO3 is a typical AFM insulator. Magnetic-field dependence and temperature dependence of transport measurements indicate that magnon dynamics and interfacial Rashba splitting are two individual origins for AFM UMR, which is consistent with the UMR theory in ferromagnetic systems. We further established a comprehensive theoretical model that incorporates micromagnetic simulation, density functional theory calculation, and the tight-binding model, which explain the observed AFM UMR phenomenon well. Our work sheds light on the intrinsic transport property of the AFM system and may facilitate the development of AFM spintronic devices.

6.
Nano Lett ; 23(10): 4258-4266, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37158610

RESUMO

Magnetic skyrmions are scarcely investigated for single-crystal quality films, for which skyrmions may have a remarkable performance. Even in the limited studies in this aspect, the skyrmions are usually probed by the topological Hall effect, missing important information on dynamic properties. Here, we present a comprehensive investigation on the generation/manipulation of magnetic skyrmions in La0.67Ba0.33MnO3 single-crystal films. Using the technique of magnetic force microscopy, the current-driven skyrmion dynamics are directly observed. Unlike isolated skyrmions produced by magnetic field alone, closely packed skyrmions can be generated by electric pulses in a magnetic background, with a high density (∼60/µm2) and a small size (dozens of nanometers). The threshold current moving skyrmions is ∼2.3 × 104 A/cm2, 2-3 orders of magnitude lower than that required by metallic multilayers or van der Waals ferromagnetic heterostructures. Our work demonstrates the great potential of single-crystal oxide films in developing skyrmion-based devices.

7.
Environ Geochem Health ; 46(6): 193, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696028

RESUMO

Microplastics (MPs) and copper (Cu) pollution coexist widely in cultivation environment. In this paper, polyvinyl chloride (PVC) were used to simulate the MPs exposure environment, and the combined effects of MPs + Cu on the germination of perilla seeds were analyzed. The results showed that low concentrations of Cu promoted seed germination, while medium to high concentrations exhibited inhibition and deteriorated the morphology of germinated seeds. The germination potential, germination index and vitality index of 8 mg • L-1 Cu treatment group with were 23.08%, 76.32% and 65.65%, respectively, of the control group. The addition of low concentration PVC increased the above indicators by 1.27, 1.15, and 1.35 times, respectively, while high concentration addition led to a decrease of 65.38%, 82.5%, and 66.44%, respectively. The addition of low concentration PVC reduced the amount of PVC attached to radicle. There was no significant change in germination rate. PVC treatment alone had no significant effect on germination. MPs + Cu inhibited seed germination, which was mainly reflected in the deterioration of seed morphology. Cu significantly enhanced antioxidant enzyme activity, increased reactive oxygen species (ROS) and MDA content. The addition of low concentration PVC enhanced SOD activity, reduced MDA and H2O2 content. The SOD activity of the Cu2+8 + PVC10 group was 4.05 and 1.35 times higher than that of the control group and Cu treatment group at their peak, respectively. At this time, the CAT activity of the Cu2+8 + PVC5000 group increased by 2.66 and 1.42 times, and the H2O2 content was 2.02 times higher than the control. Most of the above indicators reached their peak at 24 h. The activity of α-amylase was inhibited by different treatments, but ß-amylase activity, starch and soluble sugar content did not change regularly. The research results can provide new ideas for evaluating the impact of MPs + Cu combined pollution on perilla and its potential ecological risk.


Assuntos
Cobre , Germinação , Perilla , Cloreto de Polivinila , Sementes , Germinação/efeitos dos fármacos , Cobre/toxicidade , Sementes/efeitos dos fármacos , Perilla/efeitos dos fármacos , Microplásticos/toxicidade , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Malondialdeído/metabolismo , Poluentes do Solo/toxicidade
8.
Angew Chem Int Ed Engl ; : e202410514, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38966937

RESUMO

Organic scintillators are praised for their abundant element reserves, facile preparation procedures, and rich structures. However, the weak X-ray attenuation ability and low exciton utilization efficiency result in unsatisfactory scintillation performance. Herein, a new family of highly efficient organic phosphonium halide salts with thermally activated delayed fluorescence (TADF) are designed by innovatively adopting quaternary phosphonium as the electron acceptor, while dimethylamine group and halide anions (I-) serve as the electron donor. The prepared butyl(2-[2-(dimethylamino)phenyl]phenyl)diphenylphosphonium iodide (C4-I) exhibits bright blue emission and an ultra-high photoluminescence quantum yield (PLQY) of 100 %. Efficient charge transfer is realized through the unique n-π and anion-π stacking in solid-state C4-I. Photophysical studies of C4-I suggest that the incorporation of I accounts for high intersystem crossing rate (kISC) and reverse intersystem crossing rate (kRISC), suppressing the intrinsic prompt fluorescence and enabling near-pure TADF emission at room temperature. Benefitting from the large Stokes shift, high PLQY, efficient exciton utilization, and remarkable X-ray attenuation ability endowed by I, C4-I delivers an outstanding light yield of 80721 photons/MeV and a low limit of detection (LoD) of 22.79 nGy ⋅ s-1. This work would provide a rational design concept and open up an appealing road for developing efficient organic scintillators with tunable emission, strong X-ray attenuation ability, and excellent scintillator performance.

9.
Metab Brain Dis ; 38(2): 631-639, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36374407

RESUMO

Single-nucleotide polymorphisms (SNPs) of microRNAs (miRNAs) may alter miRNA transcription, maturation and target specificity, thus affecting stroke susceptibility. We aimed to investigate whether miR-200b and miR-495 SNPs may be associated with ischemic stroke (IS) risk and further explore underlying mechanisms including related genes and pathways. MiR-200b rs7549819 and miR-495 rs2281611 polymorphisms were genotyped among 712 large-artery atherosclerosis (LAA) stroke patients and 1,076 controls in a case-control study. Bioinformatic analyses were performed to explore potential association of miR-200b/495 with IS and to examine the effects of these two SNPs on miR-200b/495. Furthermore, we evaluated the association between these two SNPs and stroke using the public GWAS datasets. In our case-control study, rs7549819 was significantly associated with a decreased risk of LAA stroke (OR = 0.73, 95% CI = 0.58-0.92; p = 0.007), while rs2281611 had no significant association with LAA stroke risk. These results were consistent with the findings in East Asians from the GIGASTROKE study. Combined effects analysis revealed that individuals with 2-4 protective alleles (miR-200bC and miR-495 T) exhibited lower risk of LAA stroke than those with 0-1 variants (OR = 0.76, 95% CI = 0.61-0.96; p = 0.021). Bioinformatic analyses showed that miR-200b and miR-495 were significantly associated with genes and pathways related to IS pathogenesis, and rs7549819 and rs2281611 markedly influenced miRNA expression and structure. MiR-200b rs7549819 polymorphism and the combined genotypes of miR-200b rs7549819 and miR-495 rs2281611 polymorphisms were associated with decreased risk of LAA stroke in Chinese population.


Assuntos
Aterosclerose , AVC Isquêmico , MicroRNAs , Humanos , Artérias , Aterosclerose/genética , Estudos de Casos e Controles , AVC Isquêmico/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único/genética
10.
Int J Mol Sci ; 24(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37108715

RESUMO

As a kind of orchid plant with both medicinal and ornamental value, Dendrobium officinale has garnered increasing research attention in recent years. The MYB and bHLH transcription factors play important roles in the synthesis and accumulation of anthocyanin. However, how MYB and bHLH transcription factors work in the synthesis and accumulation of anthocyanin in D. officinale is still unclear. In this study, we cloned and characterized one MYB and one bHLH transcription factor, namely, D. officinale MYB5 (DoMYB5) and D. officinaleb bHLH24 (DobHLH24), respectively. Their expression levels were positively correlated with the anthocyanin content in the flowers, stems, and leaves of D. officinale varieties with different colors. The transient expression of DoMYB5 and DobHLH24 in D. officinale leaf and their stable expression in tobacco significantly promoted the accumulation of anthocyanin. Both DoMYB5 and DobHLH24 could directly bind to the promoters of D. officinale CHS (DoCHS) and D. officinale DFR (DoDFR) and regulate DoCHS and DoDFR expression. The co-transformation of the two transcription factors significantly enhanced the expression levels of DoCHS and DoDFR. DoMYB5 and DobHLH24 may enhance the regulatory effect by forming heterodimers. Drawing on the results of our experiments, we propose that DobHLH24 may function as a regulatory partner by interacting directly with DoMYB5 to stimulate anthocyanin accumulation in D. officinale.


Assuntos
Dendrobium , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Antocianinas/metabolismo , Dendrobium/genética , Dendrobium/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
11.
J Stroke Cerebrovasc Dis ; 32(6): 107136, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37068323

RESUMO

OBJECTIVES: We employed Mendelian randomization to determine whether genetically predicted circulating levels of endothelial-derived adhesion molecules (soluble intercellular adhesion molecule-1 [sICAM-1]), soluble vascular-leukocyte adhesion molecule-1 [sVCAM-1], and soluble-endothelial-leukocyte adhesion molecule [sE-selectin]) were associated with functional outcome after ischemic stroke. METHODS: Independent genetic variants robustly associated with soluble adhesion molecules, located at or close to the coding gene (cis), were used as genetic instruments. The functional outcome was evaluated using the 3-month modified Rankin Scale (mRS) score after ischemic stroke. A poor functional outcome was defined as mRS ≥ 3 at 3 months. We extracted summary data for functional outcome after ischemic stroke from the Genetics of Ischaemic Stroke Functional Outcome network (n = 6,021). RESULTS: Genetically elevated sICAM-1 (OR 1.28, 95% CI 1.05-1.56) and sE-selectin (OR 2.69, 95% CI 1.23-5.86) levels were related with poor post-stroke outcome. However, we found no evidence that genetically elevated sVCAM-1 were associated with post-stroke outcome (OR 1.36, 95% CI 0.39-4.66). CONCLUSIONS: We found that genetically elevated higher sICAM-1 and sE-selectin levels are associated with poor post-stroke outcome. Further studies are warranted to evaluate the potential of ICAM-1 and E-selectin to be drug targets for post-stroke recovery.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Molécula 1 de Adesão de Célula Vascular/genética , AVC Isquêmico/diagnóstico , AVC Isquêmico/genética , AVC Isquêmico/terapia , Análise da Randomização Mendeliana , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/terapia , Moléculas de Adesão Celular/genética , Molécula 1 de Adesão Intercelular/genética , Selectinas
12.
Angew Chem Int Ed Engl ; 62(7): e202216504, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36504433

RESUMO

Glass is a group of materials with appealing qualities, including simplicity in fabrication, durability, and high transparency, and they play a crucial role in the optics field. In this paper, a new organic-inorganic metal halide luminescent glass exhibiting >78 % transmittance at 506-800 nm range together with a high photoluminescence quantum yield (PLQY) of 28.5 % is reported through a low-temperature melt-quenching approach of pre-synthesized (HTPP)2 MnBr4 (HTPP=hexyltriphenylphosphonium) single crystal. Temperature-dependent X-ray diffraction, polarizing microscopy, and molecular dynamics simulations were combined to investigate the glass-crystal interconversion process, revealing the disordered nature of the glassy state. Benefiting from the transparent nature, (HTPP)2 MnBr4 glass yields an outstanding spatial resolution of 10 lp mm-1 for X-ray imaging. The superb optical properties and facility of large-scale fabrication distinguish the organic-inorganic metal halide glass as a highly promising class of materials for optical devices.

13.
Cell Mol Neurobiol ; 42(6): 1801-1807, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33620673

RESUMO

Convincing evidence has shown that microRNAs (miRNAs) are involved in the pathogenesis of stroke. This study aimed to examine whether miRNA biogenesis genes polymorphisms are associated with risk of large artery atherosclerosis (LAA) stroke. Three polymorphisms (DROSHA rs10719 T>C, RAN rs3803012 A>G, and PIWIL1 rs10773771 C>T) were screened by certain criteria. A total of 1,785 (710 cases and 1,075 controls) study subjects were included in this study. We found that rs10773771 CC genotype was associated with a decreased risk of LAA stroke (CC vs. TT/CT: OR 0.63, 95% CI 0.46-0.86, P = 3 × 10-3). In silico analysis suggested that rs10773771 can change the mRNA secondary structure of PIWIL1 and affect the binding of the miRNAs and regulatory motifs to the 3'-UTR of PIWIL1. Expression quantitative trait loci analysis showed that rs10773771 could change the expression of PIWIL1 in human skin (P = 1.534 × 10-10) and thyroid tissues (P = 4.869 × 10-6). These findings suggested that PIWIL1 rs10773771 may be associated with a decreased risk of LAA stroke.


Assuntos
Proteínas Argonautas , Aterosclerose , MicroRNAs , Acidente Vascular Cerebral , Regiões 3' não Traduzidas , Proteínas Argonautas/genética , Artérias/metabolismo , Artérias/patologia , Aterosclerose/complicações , Aterosclerose/genética , Aterosclerose/patologia , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Humanos , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Acidente Vascular Cerebral/complicações
14.
Inorg Chem ; 61(1): 338-345, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34927416

RESUMO

Low-dimensional organic-inorganic metal halides have recently emerged as a class of promising luminescent materials. However, the intrinsic toxicity of lead would strongly hamper future application. Herein, we synthesized a new type of lead-free zero-dimensional (0D) antimony-based organic-inorganic metal halide single crystals, (PPZ)2SbCl7·5H2O (PPZ = 1-phenylpiperazine), which features a broadband emission at 720 nm. Ultrafast transient absorption and temperature-dependent photoluminescence (PL) spectra are combined to investigate the PL mechanism, revealing that self-trapped exciton recombination was involved. Furthermore, it is interesting that (PPZ)2SbCl7·5H2O material shows reversible PL emission transformation between red light (720 nm) and yellow light (590 nm) as water molecules are inserted or removed from the lattice. Such reversible emission transformation phenomenon renders the (PPZ)2SbCl7·5H2O as a potential low-cost water sensing material.

15.
Acta Neurochir (Wien) ; 164(4): 1069-1078, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34448914

RESUMO

OBJECTIVE: A smartphone augmented reality (AR) application (app) was explored for clinical use in presurgical planning and lesion scalp localization. METHODS: We programmed an AR App on a smartphone. The accuracy of the AR app was tested on a 3D-printed head model, using the Euclidean distance of displacement of virtual objects. For clinical validation, 14 patients with brain tumors were included in the study. Preoperative MRI images were used to generate 3D models for AR contents. The 3D models were then transferred to the smartphone AR app. Tumor scalp localization was marked, and a surgical corridor was planned on the patient's head by viewing AR images on the smartphone screen. Standard neuronavigation was applied to evaluate the accuracy of the smartphone. Max-margin distance (MMD) and area overlap ratio (AOR) were measured to quantitatively validate the clinical accuracy of the smartphone AR technique. RESULTS: In model validation, the total mean Euclidean distance of virtual object displacement using the smartphone AR app was 4.7 ± 2.3 mm. In clinical validation, the mean duration of AR app usage was 168.5 ± 73.9 s. The total mean MMD was 6.7 ± 3.7 mm, and total mean AOR was 79%. CONCLUSIONS: The smartphone AR app provides a new way of experience to observe intracranial anatomy in situ, and it makes surgical planning more intuitive and efficient. Localization accuracy is satisfactory with lesions larger than 15 mm.


Assuntos
Realidade Aumentada , Neoplasias Encefálicas , Cirurgia Assistida por Computador , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Humanos , Imageamento Tridimensional/métodos , Neuronavegação/métodos , Couro Cabeludo/diagnóstico por imagem , Couro Cabeludo/patologia , Couro Cabeludo/cirurgia , Smartphone , Cirurgia Assistida por Computador/métodos
16.
Bioprocess Biosyst Eng ; 45(3): 503-514, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35031864

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had severe consequences for health and the global economy. To control the transmission, there is an urgent demand for early diagnosis and treatment in the general population. In the present study, an automatic system for SARS-CoV-2 diagnosis is designed and built to deliver high specification, high sensitivity, and high throughput with minimal workforce involvement. The system, set up with cross-priming amplification (CPA) rather than conventional reverse transcription-polymerase chain reaction (RT-PCR), was evaluated using more than 1000 real-world samples for direct comparison. This fully automated robotic system performed SARS-CoV-2 nucleic acid-based diagnosis with 192 samples in under 180 min at 100 copies per reaction in a "specimen in data out" manner. This throughput translates to a daily screening capacity of 800-1000 in an assembly-line manner with limited workforce involvement. The sensitivity of this device could be further improved using a CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)-based assay, which opens the door to mixed samples, potentially include SARS-CoV-2 variants screening in extensively scaled testing for fighting COVID-19.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2 , Algoritmos , Engenharia Biomédica/instrumentação , Engenharia Biomédica/métodos , Engenharia Biomédica/estatística & dados numéricos , COVID-19/epidemiologia , COVID-19/virologia , Teste de Ácido Nucleico para COVID-19/instrumentação , Teste de Ácido Nucleico para COVID-19/estatística & dados numéricos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Desenho de Equipamento , Ensaios de Triagem em Larga Escala/instrumentação , Ensaios de Triagem em Larga Escala/métodos , Ensaios de Triagem em Larga Escala/estatística & dados numéricos , Humanos , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Amplificação de Ácido Nucleico/estatística & dados numéricos , Pandemias , Robótica/instrumentação , Robótica/métodos , Robótica/estatística & dados numéricos , SARS-CoV-2/genética , Sensibilidade e Especificidade , Análise de Sistemas
17.
Sensors (Basel) ; 22(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36502231

RESUMO

With the intense deployment of wireless systems and the widespread use of intelligent equipment, the requirement for indoor positioning services is increasing, and Wi-Fi fingerprinting has emerged as the most often used approach to identifying indoor target users. The construction time of the Wi-Fi received signal strength (RSS) fingerprint database is short, but the positioning performance is unstable and susceptible to noise. Meanwhile, to strengthen indoor positioning precision, a fingerprints algorithm based on a convolution neural network (CNN) is often used. However, the number of reference points participating in the location estimation has a great influence on the positioning accuracy. There is no standard for the number of reference points involved in position estimation by traditional methods. For the above problems, the grayscale images corresponding to RSS and angle of arrival are fused into RGB images to improve stability. This paper presents a position estimation method based on the density-based spatial clustering of applications with noise (DBSCAN) algorithm, which can select appropriate reference points according to the situation. DBSCAN analyses the CNN output and can choose the number of reference points based on the situation. Finally, the position is approximated using the weighted k-nearest neighbors. The results show that the calculation error of our proposed method is at least 0.1-0.3 m less than that of the traditional method.


Assuntos
Algoritmos , Redes Neurais de Computação , Análise Espacial , Análise por Conglomerados , Bases de Dados Factuais
18.
Anal Chem ; 93(14): 5882-5889, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33797871

RESUMO

An electric double layer (EDL) generally exists at the interface between a conductive electrode and its adjacent liquid electrolyte. Accurate measurement of the capacitance of EDL is requisite but a great challenge due to the complexity of its variation mechanism correlated with the magnitude and frequency of applied signals and the difficulty in measuring the inner layer potentials across the EDL. Herein, a novel dielectrophoresis (DEP)-based approach is proposed to measure the capacitance of an EDL at a microelectrode/electrolyte interface. The measurement is achieved by employing DEP manipulation to micro polystyrene (PS) spheres suspended in a liquid electrolyte and determining the capacitance of EDL on the microelectrodes from the moving velocities of spheres. This method allows measurement of the capacitances of EDL under alternating current (AC) signals with different magnitudes and frequencies, so that the capacitance change with the magnitude and frequency of the applied signal can be characterized. The method avoids the impedance interference from the liquid electrolyte, external measuring systems, and other crosstalks, enabling an accurate measurement of double layer capacitance. In addition, the inner layer potentials across EDL under different magnitudes and frequencies of applied signals are comprehensively investigated, which facilitates an understanding of the ion behavior at the interfacial boundary that governs external observations of electrochemical reactions. The accurate measurement of the capacitance of EDL is of significance to explore the mechanism of interfacial functioning of electrochemical and bioelectrical devices and systems.

19.
Cell Mol Neurobiol ; 41(6): 1217-1225, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32506171

RESUMO

Collateral density variations are a major determinant of stroke outcome. Here, we explored the association of missense variants in hypoxia-induced VEGFA/VEGFR2 signaling and stroke outcome. We recruited 683 large artery atherosclerotic (LAA) stroke patients as the training set from Nanjing Stroke Registry Program between August 2013 and January 2016. To validate the findings from the training set, we recruited an additional 333 LAA stroke patients between February 2016 and January 2017 as the validation set. Genotyping of target SNPs (rs11549465 [HIF-1α], rs11549467 [HIF-1α], rs1870377 [VEGFR2], and rs2305948 [VEGFR2]) was conducted using a SNPscan method. Unfavorable outcome was defined as a modified Rankin Scale (mRS) score > 2 at three months after index event. In the training set, the AA genotype of rs1870377 led to a decreased risk of unfavorable outcomes in the recessive model (AA vs. TA + TT, OR 0.60, 95% CI 0.38-0.95, P = 0.031). This was confirmed in the validation set (OR 0.43, 95% CI 0.21-0.86, P = 0.017) and the combined set (OR 0.54, 95% CI 0.36-0.79, P = 0.002). We also found that A allele was a protective factor for stroke outcome in both validation set and combined set (OR 0.70, 95% CI 0.49-0.99, P = 0.044 and OR 0.77, 95% CI 0.63-0.94, P = 0.012, respectively). In silico analysis indicated that the rs1870377 variant led to structural alterations in VEGFR2 that may influence its activity. Our findings demonstrate that the rs1870377 in the hypoxia-induced VEGFA/VEGFR2 axis predicts the 3-month outcome of patients with LAA stroke.


Assuntos
Arteriosclerose Intracraniana/genética , Mutação de Sentido Incorreto/genética , Acidente Vascular Cerebral/genética , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Hipóxia Celular/fisiologia , Feminino , Seguimentos , Predisposição Genética para Doença/genética , Humanos , Arteriosclerose Intracraniana/metabolismo , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Valor Preditivo dos Testes , Transdução de Sinais/fisiologia , Acidente Vascular Cerebral/metabolismo , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
20.
Epilepsia ; 62(6): 1362-1368, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33818779

RESUMO

OBJECTIVE: Observational studies have suggested that increased levels of education and cognition are associated with a reduced risk of epilepsy. However, such associations are easily influenced by confounding or reverse causality. Hence, we conducted a two-sample univariable and multivariable Mendelian randomization (MR) to estimate the total and independent causal effects of educational attainment and cognition on epilepsy risk. METHODS: We performed MR estimates on International League Against Epilepsy (ILAE) Consortium genome-wide association study (GWAS) data (15 212 epilepsy cases and 29 677 controls). We then validated the results in FinnGen (3424 epilepsy cases and 110 963 controls) and applied meta-analysis to all the results. RESULTS: In the meta-analysis of the ILAE and FinnGen results, genetically determined increased educational attainment was associated with a reduced risk of epilepsy (odds ratio [OR] 0.84, 95% confidence interval [CI] 0.80-0.88; P < .001). Similarly, genetically determined increased cognitive function was associated with a reduced risk of epilepsy (OR 0.94, 95% CI 0.88-1.00, P = .043). When educational attainment and cognitive function were included in the same multivariable MR, only educational attainment was still associated with a reduced risk of epilepsy (OR 0.88, 95% CI 0.81-0.95, P = .002). SIGNIFICANCE: This MR study provides evidence to support that increased educational attainment can reduce the risk of developing epilepsy independent of cognitive function.


Assuntos
Cognição , Escolaridade , Epilepsia/prevenção & controle , Epilepsia/psicologia , Causalidade , Estudos de Coortes , Epilepsia/genética , Estudo de Associação Genômica Ampla , Humanos , Análise da Randomização Mendeliana , Testes Neuropsicológicos , Polimorfismo de Nucleotídeo Único , Medição de Risco , População Branca
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