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1.
Environ Int ; 187: 108651, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38648692

RESUMO

BACKGROUND: Air pollution is a recognized risk factor for cardiovascular disease (CVD). Temperature is also linked to CVD, with a primary focus on acute effects. Despite the close relationship between air pollution and temperature, their health effects are often examined separately, potentially overlooking their synergistic effects. Moreover, fewer studies have performed mixture analysis for multiple co-exposures, essential for adjusting confounding effects among them and assessing both cumulative and individual effects. METHODS: We obtained hospitalization records for residents of 14 U.S. states, spanning 2000-2016, from the Health Cost and Utilization Project State Inpatient Databases. We used a grouped weighted quantile sum regression, a novel approach for mixture analysis, to simultaneously evaluate cumulative and individual associations of annual exposures to four grouped mixtures: air pollutants (elemental carbon, ammonium, nitrate, organic carbon, sulfate, nitrogen dioxide, ozone), differences between summer and winter temperature means and their long-term averages during the entire study period (i.e., summer and winter temperature mean anomalies), differences between summer and winter temperature standard deviations (SD) and their long-term averages during the entire study period (i.e., summer and winter temperature SD anomalies), and interaction terms between air pollutants and summer and winter temperature mean anomalies. The outcomes are hospitalization rates for four prevalent CVD subtypes: ischemic heart disease, cerebrovascular disease, heart failure, and arrhythmia. RESULTS: Chronic exposure to air pollutant mixtures was associated with increased hospitalization rates for all CVD subtypes, with heart failure being the most susceptible subtype. Sulfate, nitrate, nitrogen dioxide, and organic carbon posed the highest risks. Mixtures of the interaction terms between air pollutants and temperature mean anomalies were associated with increased hospitalization rates for all CVD subtypes. CONCLUSIONS: Our findings identified critical pollutants for targeted emission controls and suggested that abnormal temperature changes chronically affected cardiovascular health by interacting with air pollution, not directly.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Doenças Cardiovasculares , Hospitalização , Estações do Ano , Temperatura , Hospitalização/estatística & dados numéricos , Doenças Cardiovasculares/epidemiologia , Humanos , Poluentes Atmosféricos/análise , Estados Unidos/epidemiologia , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Pessoa de Meia-Idade , Masculino , Feminino , Idoso , Material Particulado/análise , Adulto
2.
ACS Appl Mater Interfaces ; 16(5): 5869-5880, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38277475

RESUMO

Structural conjugation greatly affects the optical and electronic properties of the COF photocatalyst. Herein, we show that 2D hydrazone COFs with either π-extended biphenyl (BPh-COF) or acetylene (AC-COF) frameworks demonstrated distinct charge transfer and photocatalytic performances. The two COFs show good crystallinity and decent porosity as their frameworks are enforced by intra/interlayers hydrogen bonding. However, computational and experimental data reveal that AC-COF managed broader visible-light absorption and narrower optical bandgaps and performed efficient photoinduced charge separation and transfer in comparison with BPh-COF, meaning that the ethynyl skeleton with enhanced planarity better improves the π-conjugation of the whole structure. As a result, AC-COF exhibited an ideal bandgap for rapid oxidative coupling of amines under visible-light irradiation. Furthermore, taking advantage of its better charge transfer properties, AC-COF demonstrated considerable enhanced product conversion and notable functional tolerance for metallaphotocatalytic C-O cross-coupling of a wide range of both aryl bromides and chlorides with alcohols. More importantly, besides being recoverable, AC-COF showcased the previously inaccessible etherification of dihaloarene. This report shows a facile approach for manipulating the structure-activity relationship and paves the way for the development of a COF photocatalyst for solar-to-chemical energy conversion.

3.
Angew Chem Int Ed Engl ; 63(8): e202315599, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38169100

RESUMO

Polypeptides, as natural polyelectrolytes, are assembled into tailored proteins to integrate chromophores and catalytic sites for photosynthesis. Mimicking nature to create the water-soluble nanoassemblies from synthetic polyelectrolytes and photocatalytic molecular species for artificial photosynthesis is still rare. Here, we report the enhancement of the full-spectrum solar-light-driven H2 production within a supramolecular system built by the co-assembly of anionic metalloporphyrins with cationic polyelectrolytes in water. This supramolecular photocatalytic system achieves a H2 production rate of 793 and 685 µmol h-1 g-1 over 24 h with a combination of Mg or Zn porphyrin as photosensitizers and Cu porphyrin as a catalyst, which is more than 23 times higher than that of free molecular controls. With a photosensitizer to catalyst ratio of 10000 : 1, the highest H2 production rate of >51,700 µmol h-1 g-1 with a turnover number (TON) of >1,290 per molecular catalyst was achieved over 24 h irradiation. The hierarchical self-assembly not only enhances photostability through forming ordered stackings of the metalloporphyrins but also facilitates both energy and electron transfer from antenna molecules to catalysts, and therefore promotes the photocatalysis. This study provides structural and mechanistic insights into the self-assembly enhanced photostability and catalytic performance of supramolecular photocatalytic systems.

4.
Adv Mater ; 36(16): e2311659, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38175183

RESUMO

Enamel repair is crucial for restoring tooth function and halting dental caries. However, contemporary research often overlooks the retention of organic residues within the repair layer, which hinders the growth of dense crystals and compromises the properties of the repaired enamel. During the maturation of natural enamel, the organic matrix undergoes enzymatic processing to facilitate further crystal growth, resulting in a highly mineralized tissue. Inspired by this process, a biomimetic self-maturation mineralization system is developed, comprising ribonucleic acid-stabilized amorphous calcium phosphate (RNA-ACP) and ribonuclease (RNase). The RNA-ACP induces initial mineralization in the form of epitaxial crystal growth, while the RNase present in saliva automatically triggers a biomimetic self-maturation process. The mechanistic study further indicates that RNA degradation prompts conformational rearrangement of the RNA-ACP, effectively excluding the organic matter introduced earlier. This exclusion process promotes lateral crystal growth, resulting in the generation of denser enamel-like apatite crystals that are devoid of organic residues. This strategy of eliminating organic residues from enamel crystals enhances the mechanical and physiochemical properties of the repaired enamel. The present study introduces a conceptual biomimetic mineralization strategy for effective enamel repair in clinical practice and offers potential insights into the mechanisms of biomineral formation.


Assuntos
Biomimética , Fosfatos de Cálcio , Cárie Dentária , Humanos , RNA , Ribonucleases , Esmalte Dentário
5.
Photoacoustics ; 34: 100571, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38035174

RESUMO

An all-optical non-resonant photoacoustic spectroscopy system for multicomponent gas detection based on a silicon cantilever optical microphone (SCOM) and an aseismic photoacoustic cell is proposed and demonstrated. The SCOM has a high sensitivity of over 96.25 rad/Pa with sensitivity fluctuation less than ± 1.56 dB between 5 Hz and 250 Hz. Besides, the minimal detectable pressure (MDP) of the sensor is 0.55 µPa·Hz-1/2 at 200 Hz, which indicates that the fabricated sensor has high sensitivity and low noise level. Six different gases of CO2, CO, CH4, C2H6, C2H4, C2H2 are detected at the frequency of 10 Hz, whose detection limits (3σ) are 62.66 ppb, 929.11 ppb, 1494.97 ppb, 212.94 ppb, 1153.36 ppb and 417.61 ppb, respectively. The system achieves high sensitivity and low detection limits for trace gas detection. In addition, the system exhibits seismic performance with suppressing vibration noise by 4.5 times, and achieves long-term stable operation. The proposed non-resonant all-optical PAS multi-component gas detection system exhibits the advantages of anti-vibration performance, low gas consumption and long term stability, which provides a solution for working in complex environments with inherently safe.

6.
EClinicalMedicine ; 65: 102305, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37965431

RESUMO

Background: Glibenclamide alleviates brain edema and improves neurological outcomes in experimental models of stroke. We aimed to assess whether glibenclamide improves functional outcomes in patients with acute ischemic stroke treated with recombinant tissue plasminogen activator (rtPA). Methods: In this randomized, double-blind, placebo-controlled trial, patients with acute ischemic stroke were recruited to eight academic hospitals in China. Patients were eligible if they were aged 18-74 years, presented with a symptomatic anterior circulation occlusion with a deficit on the NIHSS of 4-25, and had been treated with rtPA within 4.5 h of symptom onset. We used web-based randomization (1:1) to allocate eligible participants to the glibenclamide or placebo group, stratified according to endovascular treatment and baseline stroke severity. Glibenclamide or placebo was taken orally or via tube feeding at a loading dose of 1.25 mg within 10 h after symptom onset, followed by 0.625 mg every 8 h for 5 days. The primary outcome was the proportion of patients with good outcomes (modified Rankin Scale of 0-2) at 90 days, assessed in all randomly assigned patients who had been correctly diagnosed and had begun study medication. The study is registered with ClinicalTrials.gov, NCT03284463, and is closed to new participants. Findings: Between January 1, 2018, and May 28, 2022, 305 patients were randomly assigned, of whom 272 (142 received glibenclamide and 130 received placebo) were included in the primary efficacy analysis. 103 (73%) patients in the glibenclamide group and 94 (72%) in the placebo group had a good outcome (adjusted risk difference 0.002, 95% CI -0.098 to 0.103; p = 0.96). 12 (8%) patients allocated to glibenclamide and seven (5%) patients allocated to placebo died from any cause at 90 days (p = 0.35). The number and type of adverse events were similar between the two groups. There were no drug-related adverse events and no drug-related deaths. Interpretation: The addition of glibenclamide to thrombolytic therapy did not increase the proportion of patients who achieved good outcomes after stroke compared with placebo, but it did not lead to any safety concerns. Funding: Southern Medical University and Nanfang Hospital.

7.
Medicine (Baltimore) ; 102(42): e34988, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37861560

RESUMO

RATIONALE: Refractory hypotension is a life-threatening condition that can result from various causes. We report a rare case of refractory hypotension following herpes simplex virus type 1 encephalitis that was successfully treated with hormone therapy. PATIENT CONCERNS: The patient was a 66-year-old male who was admitted to the hospital because of fever, chills, convulsions, and impaired consciousness. He developed respiratory failure and was intubated. Cerebrospinal fluid metagenomic sequencing confirmed herpes simplex virus type 1 infection. He received piperacillin-tazobactam for anti-infection, acyclovir for antiviral therapy, and dexamethasone for anti-inflammatory therapy. He had repeated episodes of hypotension despite fluid resuscitation and vasopressor therapy. DIAGNOSIS: The diagnosis of herpes simplex virus type 1 encephalitis complicated by refractory hypotension was based on the patient's epidemiological history, clinical manifestations, laboratory tests, and imaging studies. Cerebrospinal fluid examination was the most important diagnostic method, which could detect viral nucleic acids. Head magnetic resonance imaging showed a large recent lesion in the right temporal-parietal and insular lobes. INTERVENTIONS: The treatment of refractory hypotension mainly included anti-infection, antiviral, anti-inflammatory, and hormone therapy. Hormone therapy used methylprednisolone shock treatment until tapering withdrawal. Other treatments included fluid resuscitation, vasopressors, anticonvulsants, etc. OUTCOMES: The patient's blood pressure stabilized after receiving methylprednisolone shock treatment, and his mean arterial pressure increased from 73 mm Hg to 92 mm Hg within 24 hours. Three months later, the patient's blood pressure was normal without medication, and he had a good social and physical recovery. LESSONS: This case illustrates the possible role of hormone therapy in restoring blood pressure in patients with refractory hypotension following viral encephalitis. It suggests that adrenal insufficiency or autonomic dysfunction may be involved in the pathophysiology of this condition. Further studies are needed to confirm the efficacy and safety of hormone therapy in this setting.


Assuntos
Encefalite por Herpes Simples , Encefalite Viral , Hipotensão , Masculino , Humanos , Idoso , Aciclovir/uso terapêutico , Encefalite por Herpes Simples/tratamento farmacológico , Encefalite Viral/diagnóstico , Encefalite Viral/tratamento farmacológico , Metilprednisolona/uso terapêutico , Hipotensão/etiologia , Hipotensão/complicações , Anti-Inflamatórios/uso terapêutico , Hormônios/uso terapêutico , Antivirais/uso terapêutico
8.
Chemosphere ; 344: 140320, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37775052

RESUMO

Agricultural heavy metal contamination can cause significant crop damage, highlighting the urgent need to mitigate its negative effects. Under Cd2+ stress, selenium nanomaterials (Se NMs, 2 mg kg-1) can significantly improve Brassica chinensis L. root growth and vigor, enhance photosynthesis (31.4%), and increase biomass. Se NMs treatment also reduces Brassica chinensis L root and shoot Cd concentration by 67.2 and 72.9%, respectively. This reduction is mainly due to the gene expression of Cd2+ absorption (BcITR1 and BcHMA2) which was down-regulated 51.9 and 67.0% by Se NMs, respectively. Meanwhile, Se NMs can increase the abundance of Cd-resistant microorganisms (Gemmatimonas, RB41, Haliangium, Gaiella, and Steroidobacter) in rhizosphere soil while also reducing Cd migration from soil to plants. Additionally, Se NMs also contribute to reducing ROS accumulation by improving the oxidation-reduction process between GSH and GSSG through enhancing γ-ECS (15.6%), GPx (50.2%) and GR (97.3%) activity. Remarkably, crop Se content can reach 50.8 µg/100 g, which fully meets the standards of Se-rich vegetables. These findings demonstrate the potential of Se NMs in relieving heavy metal stress, while simultaneously increasing crop Se content, making it a promising technology for sustainable agricultural production.


Assuntos
Brassica , Selênio , Poluentes do Solo , Selênio/farmacologia , Selênio/metabolismo , Antioxidantes/metabolismo , Cádmio/toxicidade , Cádmio/metabolismo , Estresse Oxidativo , Glutationa/metabolismo , Solo , Poluentes do Solo/toxicidade
9.
BMJ Open ; 13(6): e068743, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37336540

RESUMO

INTRODUCTION: 54% of patients with moderate-to-severe knee osteoarthritis (KOA) still reported persistent pain and functional loss after conservative treatment according to guidelines. As an emerging treatment, platelet-rich plasma (PRP) has been proven to significantly relieve pain and improve activity function in patients with mild-to-moderate KOA, either used alone or in combination with hyaluronic acid (HA). However, it is still unclear of its efficacy in moderate-to-severe KOA. This study aims to evaluate the clinical efficacy of PRP and the combination therapy of PRP and HA in patients with moderate-to-severe KOA and to explore the potential synergistic effect of PRP and HA. METHODS AND ANALYSIS: This triple-blind randomised controlled trial will involve a total of 162 participants with moderate-to-severe KOA from two study centres. Participants will be allocated randomly into three groups: the HA group, the PRP group and the combination (PRP+HA) group and, respectively, receive HA (2.5 mL)+saline (3 mL)/PRP (3 mL)+saline (2.5 mL)/PRP (3 mL)+HA (2.5 mL) intra-articular injection each week for 4 consecutive weeks. All of the injections will be performed under the guidance of ultrasound. The primary outcome is the change of Western Ontario and McMaster Universities Osteoarthritis Index from baseline to 6 months, and secondary outcomes include the change of ultrasound images (suprapatellar bursa effusion and synovitis), Timed Up and Go test and 12-Item Short-Form Health Survey. All outcomes will be evaluated at baseline and 1-month, 3-month and 6-month follow-ups. Data will be analysed on intention-to-treat principles and a per-protocol basis. ETHICS AND DISSEMINATION: This protocol was approved by the Medical Ethics Committee of the Third Affiliated Hospital of Sun Yat-sen University (reference number (2021)-02-231-02). The study results will be submitted to a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ChiCTR2100050974.


Assuntos
Osteoartrite do Joelho , Plasma Rico em Plaquetas , Humanos , Osteoartrite do Joelho/terapia , Osteoartrite do Joelho/tratamento farmacológico , Ácido Hialurônico/uso terapêutico , Equilíbrio Postural , Estudos de Tempo e Movimento , Dor/tratamento farmacológico , Injeções Intra-Articulares , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Trials ; 24(1): 6, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36597103

RESUMO

BACKGROUND: Knee osteoarthritis (OA) is a prevalent disabling disorder that involves changes in articular cartilage damage, subchondral bone remodeling, synovitis, and abnormal infrapatellar fat pad (IPFP). Due to the complicated etiology and numerous phenotypes of knee OA, limited improvement is achieved for treatments among knee OA patients with different phenotypes. Inflammatory OA phenotype is a typical knee OA phenotype, and individualized treatment targeting inflammation is a promising way to obtain an optimal therapeutic effect for people with inflammatory knee OA phenotype. Glucocorticoid is a traditional anti-inflammatory drug for knee OA, and intra-articular glucocorticoid injections are recommended clinically. However, emerging evidence has shown that repeated intra-articular glucocorticoid injections in the long term would induce cartilage loss. IPFP and its adjacent synovium are considered as the main source of inflammation in knee OA. This GLITTERS trial aims to investigate if a glucocorticoid injection into the IPFP is effective and safe over 12 weeks among knee OA patients with an inflammatory phenotype. METHODS: GLITTERS is a multicenter, double-blinded, randomized, and placebo-controlled clinical trial among knee OA patients with both Hoffa-synovitis and effusion-synovitis. Sixty participants will be allocated randomly and equally to either the glucocorticoid group or the control group. Each group will receive an injection of glucocorticoid or saline into the IPFP with an intra-articular hyaluronic acid injection as a background treatment at baseline and be followed at 4, 8, and 12 weeks. The primary outcomes will be changes in knee pain on a visual analog scale and effusion-synovitis volume measured on magnetic resonance imaging (MRI). The secondary outcomes will be changes in the total score of Western Ontario and McMaster Universities Osteoarthritis Index score, MRI-detected Hoffa-synovitis score, quality of life, pain medication use, IPFP volume, and the incidence of adverse reactions. Data analyses based on the intention-to-treat principle will include mixed-effects regressions, Wilcoxon rank-sum tests, and chi-square tests (or Fisher's exact test). DISCUSSION: GLITTERS may provide high-quality evidence for the efficacy and safety of ultrasound-guided glucocorticoid injections into IPFP among people with inflammatory knee OA in a short term. The results of this trial are expected to provide a reliable reference for a longer-term risk-benefit profile of this treatment in the future. TRIAL REGISTRATION: ClinicalTrials.gov NCT05291650. Registered on 23 March 2022.


Assuntos
Osteoartrite do Joelho , Sinovite , Humanos , Osteoartrite do Joelho/terapia , Glucocorticoides/efeitos adversos , Qualidade de Vida , Dor/tratamento farmacológico , Injeções Intra-Articulares , Sinovite/diagnóstico por imagem , Sinovite/tratamento farmacológico , Sinovite/complicações , Inflamação/tratamento farmacológico , Tecido Adiposo , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
11.
Materials (Basel) ; 16(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36676587

RESUMO

The flow pattern is vital for the metallurgical performance of continuous casting tundishes. The purpose of this study was to design and optimize the flow characteristics inside a four-strand tundish. Numerical simulations and water model experiments were validated and utilized to investigate the flow behavior. The effect of different flow rates in the original tundish was evaluated; two modified retaining walls and a new ladle shroud were designed for optimization. The molten steel inside the original tundish tends to be more active as the flow rate increases from 3.8 L/min to 6.2 L/min, which results in a reduction in dead volume from 36.47% to 17.59% and better consistency between different outlets. The dead volume and outlet consistency inside the tundish are improved significantly when the modified walls are applied. The proper design of the diversion hole further enhances the plug volume from 6.39% to 13.44% of the tundish by forming an upstream circular flow in the casting zone. In addition, the new trumpet ladle shroud demonstrates an advantage in increasing the response time from 152.5 s to 167.5 s and alleviating the turbulence in the pouring zone, which is beneficial for clean steel production.

12.
Sci Total Environ ; 856(Pt 1): 159125, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36181808

RESUMO

With global warming and water scarcity, improving the drought tolerance and quality of crops is critical for food security and human health. Here, foliar application of carbon dots (CDs, 5 mg·L-1) could scavenge reactive oxygen species accumulation in soybean leaves under drought stress, thereby enhancing photosynthesis and carbohydrate transport. Moreover, CDs stimulated root secretion (e.g., amino acids, organic acids, and auxins) and recruited beneficial microorganisms (e.g., Actinobacteria, Ascomycota, Acidobacteria and Glomeromycota), which facilitate nitrogen (N) activation in the soil. Meanwhile, the expression of GmNRT, GmAMT, and GmAQP genes were up-regulated, indicating enhanced N and water uptake. The results demonstrated that CDs could promote nitrogen metabolism and enhance amino acid biosynthesis. Particularly, the N content in soybean shoots and roots increased significantly by 13.2 % and 30.5 %, respectively. The amino acids content in soybean shoots and roots increased by 257.5 % and 57.5 %, respectively. Consequently, soybean yields increased significantly by 21.5 %, and the protein content in soybean kernels improved by 3.7 %. Therefore, foliar application of CDs can support sustainable nano-enabled agriculture to combat climate change.


Assuntos
Secas , Fabaceae , Humanos , Glycine max/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Carbono/metabolismo , Fotossíntese , Fabaceae/metabolismo , Aminoácidos/metabolismo , Nitrogênio/metabolismo , Estresse Fisiológico
13.
Opt Express ; 30(26): 47587-47597, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558684

RESUMO

In this article, a fiber optic accelerometer based on a Fabry-Perot interferometer is presented and prepared by micromachining on a silicon substrate. The inertial sensing structure of the accelerometer is built by a center block mass and four folded springs with a high thickness-to-width ratio, providing an in-plane resonance vibration. The miniature-sized sensor has large flexibility in structural design and its acceleration response can be predicted by theoretical estimation and finite element simulation. Experimental results show that the proposed sensor's sensitivity is over 161 rad/g in frequency range of 1 to 63 Hz. It also achieved a low average noise level of 67.4 ng/Hz1/2 on the working band. The sensor's transverse crosstalk is less than 1.38%, proving its potential ability in low frequency vibration detection applications.

14.
Materials (Basel) ; 15(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36499915

RESUMO

Metallurgy involves the art and science of extracting metals from their ores and modifying them for use [...].

15.
Sensors (Basel) ; 22(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36366158

RESUMO

In this paper, a novel inline optical fiber sensor for curvature and temperature measurement simultaneously has been proposed and demonstrated, which can measure two parameters with very little crosstalk. Two combinational mechanisms of anti-resonant reflecting optical waveguide and inline Mach-Zehnder interference structure are integrated into a 3 mm-long single hole twin suspended core fiber (SHTSCF). The 85 µm hole core gives periodic several dominant resonant wavelengths in the optical transmission spectrum, acting as the anti-resonant reflecting optical waveguide (ARROW). The modes in two suspended cores and the cladding form the comb pattern. Reliable sensor sensitivity can be obtained by effective experiments and demodulation. Through intensity demodulation of the selected dip of Gaussian fitting, the curvature sensitivity can be up to -7.23 dB/m-1. Through tracking the MZI dip for wavelength demodulation, the temperature sensitivity can be up to 28.8 pm/°C. The sensor is simple in structure, compact, and has good response, which can have a bright application in a complex environment.

16.
Opt Express ; 30(13): 23227-23237, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36225008

RESUMO

A fiber optic accelerometer with a high sensitivity, low noise, and compact size is proposed for low-frequency acceleration sensing. The sensor is composed of a 20 mm diameter spherical outer frame and a three-dimensional spring-mass structure as the inertial sensing element. Three Fabry-Pérot interferometers (FPI) are formed between flat fiber facets and cubic mass surfaces to measure the FPI cavity length change caused by acceleration. The dynamic signal sensing of the designed accelerometer is performed, which shows a high acceleration sensitivity of 42.6 dB re rad/g with a working band of 1-80 Hz. An average minimum detectable acceleration of 4.5 µg/Hz1/2 can be obtained. The sensor features simple assembling, small size, light weight, and good consistency. Its transverse sensitivity is measured to be less than 3% (-30 dB) of the sensitive axis. The experimental result indicates that the proposed accelerometer has application potential in areas such as seismic wave detection and structural health monitoring.

17.
Photoacoustics ; 27: 100389, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36068797

RESUMO

All-optical light-induced thermoacoustic spectroscopy (AO-LITS) is reported for the first time for highly sensitive and selective gas sensing, in which a commercial standard quartz tuning fork (QTF) is employed as a photothermal detector. The vibration of the QTF was measured by the highly sensitive fiber-optic Fabry-Pérot (FP) interferometry (FPI) technique, instead of the piezoelectric detection in the conventional LITS. To improve the stability of the sensor system, a compact QTF-based fiber-optic FPI module is fabricated by 3D printing technique and a dual-wavelength demodulation method with the ellipse-fitting differential-cross-multiplication algorithm (DW-EF-DCM) is exploited for the FPI measurement. The all-optical detection scheme has the advantages of remote detection and immunity to electromagnetic interference. A minimum detection limit (MDL) of 422 ppb was achieved for hydrogen sulfide (H2S), which was ~ 3 times lower than a conventional electrical LITS sensor system. The AO-LITS can provide a promising approach for remote and non-contact gas sensing in the whole infrared spectral region.

18.
Quant Imaging Med Surg ; 12(6): 3138-3150, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35655843

RESUMO

Background: Ultrasonography-an imaging technique that can show the anatomical section of nerves and surrounding tissues-is one of the most effective imaging methods to diagnose nerve diseases. However, segmenting the median nerve in two-dimensional (2D) ultrasound images is challenging due to the tiny and inconspicuous size of the nerve, the low contrast of images, and imaging noise. This study aimed to apply deep learning approaches to improve the accuracy of automatic segmentation of the median nerve in ultrasound images. Methods: In this study, we proposed an improved network called VGG16-UNet, which incorporates a contracting path and an expanding path. The contracting path is the VGG16 model with the 3 fully connected layers removed. The architecture of the expanding path resembles the upsampling path of U-Net. Moreover, attention mechanisms or/and residual modules were added to the U-Net and VGG16-UNet, which sequentially obtained Attention-UNet (A-UNet), Summation-UNet (S-UNet), Attention-Summation-UNet (AS-UNet), Attention-VGG16-UNet (A-VGG16-UNet), Summation-VGG16-UNet (S-VGG16-UNet), and Attention-Summation-VGG16-UNet (AS-VGG16-UNet). Each model was trained on the dataset of 910 median nerve images from 19 participants and tested on 207 frames from a new image sequence. The performance of the models was evaluated by metrics including Dice similarity coefficient (Dice), Jaccard similarity coefficient (Jaccard), Precision, and Recall. Based on the best segmentation results, we reconstructed a 3D median nerve image using the volume rendering method in the Visualization Toolkit (VTK) to assist in clinical nerve diagnosis. Results: The results of paired t-tests showed significant differences (P<0.01) in the metrics' values of different models. It showed that AS-UNet ranked first in U-Net models. The VGG16-UNet and its variants performed better than the corresponding U-Net models. Furthermore, the model's performance with the attention mechanism was superior to that with the residual module either based on U-Net or VGG16-UNet. The A-VGG16-UNet achieved the best performance (Dice =0.904±0.035, Jaccard =0.826±0.057, Precision =0.905±0.061, and Recall =0.909±0.061). Finally, we applied the trained A-VGG16-UNet to segment the median nerve in the image sequence, then reconstructed and visualized the 3D image of the median nerve. Conclusions: This study demonstrates that the attention mechanism and residual module improve deep learning models for segmenting ultrasound images. The proposed VGG16-UNet-based models performed better than U-Net-based models. With segmentation, a 3D median nerve image can be reconstructed and can provide a visual reference for nerve diagnosis.

19.
Opt Lett ; 47(10): 2406-2409, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35561362

RESUMO

In this Letter, we report a four-wavelength quadrature phase demodulation technique for extrinsic Fabry-Perot interferometric (EFPI) sensors and dynamic signals. Four interferometric signals are obtained from four different laser wavelengths. A wavelength interval of four wavelengths is chosen according to the free spectrum range (FSR) of EFPI sensors to generate two groups of anti-phase signals and two groups of orthogonal signals. The linear fitting (LF) method is applied to two groups of anti-phase signals to eliminate the dc component and ac amplitude to obtain two normalized orthogonal signals. The differential cross multiplication (DCM) method is then used to demodulate the phase signal from these two normalized orthogonal signals. The proposed LF and DCM (LF-DCM) based four-wavelength quadrature phase demodulation overcomes the drawback of the traditional ellipse fitting (EF) and DCM (EF-DCM) based dual-wavelength demodulation method that it is not suitable for weak signal demodulation since the ellipse degenerates into a straight line, which makes the EF algorithm invalid. Moreover, it also avoids the assumption that the dc component and ac amplitude of interferometric signals are identical, which is widely used in three-wavelength demodulation. An EFPI acoustic sensor is tested to prove the four-wavelength quadrature phase demodulation and experimental results show that the proposed phase demodulation method shows advantages of large dynamic range and wide frequency band. Linearity is as high as 0.9999 and a high signal-to-noise ratio (SNR) is observed from 1 Hz to 100 kHz.

20.
Clin Cancer Res ; 28(14): 3156-3169, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35552677

RESUMO

PURPOSE: Paclitaxel (PTX) is one of the most potent and commonly used chemotherapies for breast and pancreatic cancer. Several ongoing clinical trials are investigating means of enhancing delivery of PTX across the blood-brain barrier for glioblastomas. Despite the widespread use of PTX for breast cancer, and the initiative to repurpose this drug for gliomas, there are no predictive biomarkers to inform which patients will likely benefit from this therapy. EXPERIMENTAL DESIGN: To identify predictive biomarkers for susceptibility to PTX, we performed a genome-wide CRISPR knockout (KO) screen using human glioma cells. The genes whose KO was most enriched in the CRISPR screen underwent further selection based on their correlation with survival in the breast cancer patient cohorts treated with PTX and not in patients treated with other chemotherapies, a finding that was validated on a second independent patient cohort using progression-free survival. RESULTS: Combination of CRISPR screen results with outcomes from patients with taxane-treated breast cancer led to the discovery of endoplasmic reticulum (ER) protein SSR3 as a putative predictive biomarker for PTX. SSR3 protein levels showed positive correlation with susceptibility to PTX in breast cancer cells, glioma cells, and in multiple intracranial glioma xenografts models. KO of SSR3 turned the cells resistant to PTX while its overexpression sensitized the cells to PTX. Mechanistically, SSR3 confers susceptibility to PTX through regulation of phosphorylation of ER stress sensor IRE1α. CONCLUSIONS: Our hypothesis generating study showed SSR3 as a putative biomarker for susceptibility to PTX, warranting its prospective clinical validation.


Assuntos
Antineoplásicos Fitogênicos , Biomarcadores Farmacológicos , Neoplasias Encefálicas , Neoplasias da Mama , Proteínas de Ligação ao Cálcio , Resistencia a Medicamentos Antineoplásicos , Glioblastoma , Glicoproteínas de Membrana , Paclitaxel , Receptores Citoplasmáticos e Nucleares , Receptores de Peptídeos , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Proteínas de Ligação ao Cálcio/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Endorribonucleases/metabolismo , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Glicoproteínas de Membrana/genética , Camundongos , Paclitaxel/uso terapêutico , Estudos Prospectivos , Proteínas Serina-Treonina Quinases/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores de Peptídeos/genética , Ensaios Antitumorais Modelo de Xenoenxerto
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