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1.
Nature ; 589(7840): 44-51, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33408378

RESUMEN

Convolutional neural networks, inspired by biological visual cortex systems, are a powerful category of artificial neural networks that can extract the hierarchical features of raw data to provide greatly reduced parametric complexity and to enhance the accuracy of prediction. They are of great interest for machine learning tasks such as computer vision, speech recognition, playing board games and medical diagnosis1-7. Optical neural networks offer the promise of dramatically accelerating computing speed using the broad optical bandwidths available. Here we demonstrate a universal optical vector convolutional accelerator operating at more than ten TOPS (trillions (1012) of operations per second, or tera-ops per second), generating convolutions of images with 250,000 pixels-sufficiently large for facial image recognition. We use the same hardware to sequentially form an optical convolutional neural network with ten output neurons, achieving successful recognition of handwritten digit images at 88 per cent accuracy. Our results are based on simultaneously interleaving temporal, wavelength and spatial dimensions enabled by an integrated microcomb source. This approach is scalable and trainable to much more complex networks for demanding applications such as autonomous vehicles and real-time video recognition.

2.
BMC Genomics ; 25(1): 670, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965476

RESUMEN

BACKGROUND: The TCP (teosinte branched1/cincinnata/proliferating cell factor) family plays a prominent role in plant development and stress responses. However, TCP family genes have thus far not been identified in castor bean, and therefore an understanding of the expression and functional aspects of castor bean TCP genes is lacking. To identify the potential biological functions of castor bean (RcTCP) TCP members, the composition of RcTCP family members, their basic physicochemical properties, subcellular localizations, interacting proteins, miRNA target sites, and gene expression patterns under stress were assessed. RESULTS: The presence of 20 RcTCP genes on the nine chromosomes of castor bean was identified, all of which possess TCP domains. Phylogenetic analysis indicated a close relationship between RcTCP genes and Arabidopsis AtTCP genes, suggesting potential functional similarity. Subcellular localization experiments confirmed that RcTC01/02/03/10/16/18 are all localized in the nucleus. Protein interaction analysis revealed that the interaction quantity of RcTCP03/06/11 proteins is the highest, indicating a cascade response in the functional genes. Furthermore, it was found that the promoter region of RcTCP genes contains a large number of stress-responsive elements and hormone-induced elements, indicating a potential link between RcTCP genes and stress response functions. qRT-PCR showed that all RcTCP genes exhibit a distinct tissue-specific expression pattern and their expression is induced by abiotic stress (including low temperature, abscisic acid, drought, and high salt). Among them, RcTCP01/03/04/08/09/10/14/15/18/19 genes may be excellent stress-responsive genes. CONCLUSION: We discovered that RcTCP genes play a crucial role in various activities, including growth and development, the stress response, and transcription. This study provides a basis for studying the function of RcTCP gene in castor.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Filogenia , Proteínas de Plantas , Ricinus communis , Estrés Fisiológico , Estrés Fisiológico/genética , Ricinus communis/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiones Promotoras Genéticas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Perfilación de la Expresión Génica
3.
Opt Express ; 32(7): 11281-11295, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38570979

RESUMEN

We report a dual-polarization radio frequency (RF) channelizer based on microcombs. Two high-Q micro-ring resonators (MRRs) with slightly different free spectral ranges (FSRs) are used: one MRR is pumped to yield soliton crystal microcombs ("active"), and the other MRR is used as a "passive" periodic optical filter supporting dual-polarization operation to slice the RF spectrum. With the tailored mismatch between the FSRs of the active and passive MRRs, wideband RF spectra can be channelized into multiple segments featuring digital-compatible bandwidths via the Vernier effect. Due to the use of dual-polarization states, the number of channelized spectral segments, and thus the RF instantaneous bandwidth (with a certain spectral resolution), can be doubled. In our experiments, we used 20 microcomb lines with ∼ 49 GHz FSR to achieve 20 channels for each polarization, with high RF spectra slicing resolutions at 144 MHz (TE) and 163 MHz (TM), respectively; achieving an instantaneous RF operation bandwidth of 3.1 GHz (TE) and 2.2 GHz (TM). Our approach paves the path towards monolithically integrated photonic RF receivers (the key components - active and passive MRRs are all fabricated on the same platform) with reduced complexity, size, and unprecedented performance, which is important for wide RF applications with digital-compatible signal detection.

4.
J Nanobiotechnology ; 22(1): 131, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38532389

RESUMEN

Effective intracellular DNA transfection is imperative for cell-based therapy and gene therapy. Conventional gene transfection methods, including biochemical carriers, physical electroporation and microinjection, face challenges such as cell type dependency, low efficiency, safety concerns, and technical complexity. Nanoneedle arrays have emerged as a promising avenue for improving cellular nucleic acid delivery through direct penetration of the cell membrane, bypassing endocytosis and endosome escape processes. Nanostraws (NS), characterized by their hollow tubular structure, offer the advantage of flexible solution delivery compared to solid nanoneedles. However, NS struggle to stably self-penetrate the cell membrane, resulting in limited delivery efficiency. Coupling with extra physiochemical perforation strategies is a viable approach to improve their performance. This study systematically compared the efficiency of NS coupled with polyethylenimine (PEI) chemical modification, mechanical force, photothermal effect, and electric field on cell membrane perforation and DNA transfection. The results indicate that coupling NS with PEI modification, mechanical force, photothermal effects provide limited enhancement effects. In contrast, NS-electric field coupling significantly improves intracellular DNA transfection efficiency. This work demonstrates that NS serve as a versatile platform capable of integrating various physicochemical strategies, while electric field coupling stands out as a form worthy of primary consideration for efficient DNA transfection.


Asunto(s)
ADN , Electroporación , Transfección , Membrana Celular , Terapia Genética , Polietileneimina/química
5.
Opt Express ; 31(22): 35971-35981, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-38017757

RESUMEN

Optical equalization can be used for chromatic dispersion compensation in optical communication systems to improve the system performance; however, optical signal processing (OSP) is generally specifically designed for transmission channels, that is non-adaptive to dynamic transmission distortions compared with digital signal processing (DSP). In this contribution, we demonstrate optical equalization using a photonic integrated circuit (PIC) filter for chromatic dispersion compensation, with static and adaptive techniques: (a) the static optical equalizer is calibrated based on the known fiber dispersion and length, by using the fractional delay reference method; (b) the adaptive optical equalizer is updated iteratively to compensate transmission impairments based on a least-mean squares (LMS) algorithm. Experimental results show that both the static optical equalizer and the adaptive optical LMS equalizer can give an 18-dB Q-factor for a 14-Gbd QPSK signal transmitting over 30 km. To highlight the capability of the optical equalizers, we use simulations to show the improvement in dispersion compensating characteristics by implementing additional taps.

6.
Hepatology ; 74(5): 2526-2543, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33829508

RESUMEN

BACKGROUND AND AIMS: Due to their inherent characteristics, the function of group-2 innate lymphoid cells (ILC2s) varies in a context-dependent manner. ILC2s are involved in certain liver diseases; however, their involvement in HCC is unknown. In the present study, we assessed the role of an HCC-derived ILC2 population in tumor progression. APPROACH AND RESULTS: Through FACS and single-cell RNA sequencing, we discovered that ILC2s were highly enriched in human HCC and correlated significantly with tumor recurrence and worse progression-free survival as well as overall survival in patients. Mass cytometry identified a subset of HCC-derived ILC2s that had lost the expression of killer cell lectin-like receptor subfamily G, member 1 (KLRG1). Distinct from their circulating counterparts, these hepatic ILC2s highly expressed CD69 and an array of tissue resident-related genes. Furthermore, reduction of E-cadherin in tumor cells caused the loss of KLRG1 expression in ILC2s, leading to their increased proliferation and subsequent accumulation in HCC sites. The KLRG1- ILC2 subset showed elevated production of chemotaxis factors, including C-X-C motif chemokine (C-X-C motif) ligand (CXCL)-2 and CXCL8, which in turn recruited neutrophils to form an immunosuppressive microenvironment, leading to tumor progression. Accordingly, restoring KLRG1 in ILC2s, inhibiting CXCL2 in ILC2s, or depleting neutrophils inhibited tumor progression in a murine HCC model. CONCLUSIONS: We identified HCC-associated ILC2s as an immune regulatory cell type that promotes tumor development, suggesting that targeting these ILC2s might lead to new treatments for HCC.


Asunto(s)
Carcinogénesis/inmunología , Carcinoma Hepatocelular/inmunología , Quimiocina CXCL2/metabolismo , Progresión de la Enfermedad , Tolerancia Inmunológica , Inmunidad Innata , Neoplasias Hepáticas/inmunología , Linfocitos/inmunología , Neutrófilos/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Animales , Carcinoma Hepatocelular/patología , Células Cultivadas , Estudios de Cohortes , Modelos Animales de Enfermedad , Femenino , Humanos , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Activación Neutrófila , Microambiente Tumoral/inmunología
7.
Mol Pharm ; 19(5): 1410-1421, 2022 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-35441510

RESUMEN

This study investigates the protective effect of poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) loaded with scutellarin (SCU), a flavone isolated from the traditional Chinese medicineErigeron breviscapus (Vant.) Hand.-Mazz., in reducing cerebral ischemia/reperfusion (I/R) injury in vivo. The focal cerebral I/R injury model was established by occluding the middle cerebral artery for 1 h in male Sprague-Dawley (SD) rats. Our SCU-PLGA NPs exhibited an extended in vitro release profile and prolonged blood circulation in rats with cerebral ischemia. More importantly, when administered intravenously once a day for 3 days, SCU-PLGA NPs increased the SCU level in the ischemic brain, compared to free SCU, resulting in a significant reduction of the cerebral infarct volume after cerebral I/R. Furthermore, SCU-PLGA NPs reversed the histopathological changes caused by cerebral I/R injury, as well as attenuated cell apoptosis in the brain tissue, as confirmed by hematoxylin and eosin, and TUNEL staining. Our findings have revealed that our injectable SCU-PLGA NPs provide promising protective effects against cerebral I/R injury, which could be used in combination with the existing conventional thrombolytic therapies to improve stroke management.


Asunto(s)
Isquemia Encefálica , Nanopartículas , Daño por Reperfusión , Administración Intravenosa , Animales , Apigenina , Isquemia Encefálica/tratamiento farmacológico , Glucuronatos , Masculino , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/prevención & control
8.
J Cell Mol Med ; 25(7): 3391-3399, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33655701

RESUMEN

CLEC10A, (C-type lectin domain family 10, member A), as the member of C-type lectin receptors (CLRs), plays a vital role in modulating innate immunity and adaptive immunity and has shown great potential as an immunotherapy target for cancers. However, there is no functional research of CLEC10A in prognostic risk, immunotherapy or any other treatment of lung adenocarcinoma (LUAD). We performed bioinformatics analysis on LUAD data downloaded from TCGA (The Cancer Genome Atlas) and GEO (Gene Expression Omnibus), and jointly analysed with online databases such as HPA, LinkedOmics, TIMER, ESTIMATE and TISIDB. We found that lower expression of CLEC10A was accompanied with worse outcomes of LUAD patients. Moreover, CLEC10A expression was significantly correlated with a variety of the tumour-infiltrating immune cells (TIICs). As a promising prognosis predictor and potential immunotherapy target, the potential influence and mechanisms of CLEC10A in LUAD deserve further exploring.


Asunto(s)
Adenocarcinoma del Pulmón/genética , Biomarcadores de Tumor/genética , Lectinas Tipo C/genética , Neoplasias Pulmonares/genética , Adenocarcinoma del Pulmón/inmunología , Adenocarcinoma del Pulmón/patología , Biomarcadores de Tumor/metabolismo , Biología Computacional , Humanos , Lectinas Tipo C/metabolismo , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Microambiente Tumoral/inmunología
9.
Small ; 16(16): e1906563, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32159916

RESUMEN

Layered 2D graphene oxide (GO) films are integrated with micro-ring resonators (MRRs) to experimentally demonstrate enhanced nonlinear optics. Both uniformly coated (1-5 layers) and patterned (10-50 layers) GO films are integrated on complementary-metal-oxide-semiconductor (CMOS)-compatible doped silica MRRs using a large-area, transfer-free, layer-by-layer GO coating method with precise control of the film thickness. The patterned devices further employ photolithography and lift-off processes to enable precise control of the film placement and coating length. Four-wave-mixing (FWM) measurements for different pump powers and resonant wavelengths show a significant improvement in efficiency of ≈7.6 dB for a uniformly coated device with 1 GO layer and ≈10.3 dB for a patterned device with 50 GO layers. The measurements agree well with theory, with the enhancement in FWM efficiency resulting from the high Kerr nonlinearity and low loss of the GO films combined with the strong light-matter interaction within the MRRs. The dependence of GO's third-order nonlinearity on layer number and pump power is also extracted from the FWM measurements, revealing interesting physical insights about the evolution of the GO films from 2D monolayers to quasi bulk-like behavior. These results confirm the high nonlinear optical performance of integrated photonic resonators incorporated with 2D layered GO films.

10.
Cancer Sci ; 110(2): 530-539, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30548441

RESUMEN

B7-H5 and its cognate receptor CD28H are T lymphocyte second signaling transduction molecules. Here we aimed to explore the function of this pathway in pancreatic cancer in vitro and in vivo, and evaluated the clinical significance in 136 patients with pancreatic ductal adenocarcinoma enrolled from January 2012 to February 2017 in our hospital. Surgical tumor specimens were collected for immunohistochemical staining to evaluate B7-H5 expression. Patients' baseline characteristics, including gender, age, tumor size, tumor location, tumor grading, clinical TNM staging, tumor infiltrating lymphocytes, CA19-9 and chemotherapy treatment, along with the subsequent follow-up data, were documented and analyzed. When co-cultured with T cells, pancreatic cancer PC cells with high B7-H5 expression induced a more potent immune reaction, indicated by elevated cytokine release and increased proliferation of T lymphocytes compared with cells exhibiting low B7-H5 expression. Xenograft pancreatic tumors derived from high B7-H5 expression PC cells exhibited attenuated growth compared to tumors from low B7-H5 expression cells after transfusion with T lymphocytes in immune-deficient mice. Of the 136 PDAC tumor tissues, 93 (68.38%) were strong and 43 (31.62%) were weak B7-H5 expression. Patients with strong B7-H5 expression had significantly longer overall survival than those with weak expression (median: 16.5 vs 11.5 months, P = .017). TNM staging, tumor location and subsequent chemotherapy were also prognostic factors in these patients. Collectively, B7-H5/CD28H is a co-stimulatory signal pathway, and expression of B7-H5 is associated with improved disease prognosis in patients with pancreatic cancer.


Asunto(s)
Adenocarcinoma/metabolismo , Antígenos B7/metabolismo , Antígenos CD28/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Transducción de Señal/fisiología , Adenocarcinoma/patología , Adulto , Anciano , Animales , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Proliferación Celular/fisiología , Femenino , Humanos , Linfocitos Infiltrantes de Tumor/metabolismo , Linfocitos Infiltrantes de Tumor/patología , Masculino , Ratones , Persona de Mediana Edad , Estadificación de Neoplasias/métodos , Pronóstico , Linfocitos T/metabolismo , Linfocitos T/patología
11.
J Immunol ; 198(5): 1798-1803, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28115527

RESUMEN

The mechanisms underlying lymphocyte lineage stability and plasticity remain elusive. Recent work indicates that innate lymphoid cells (ILC) possess substantial plasticity. Whereas natural ILC2 (nILC2) produce type-2 cytokines, plastic inflammatory ILC2 (iILC2) can coproduce both type-2 cytokines and the ILC3-characteristic cytokine, IL-17. Mechanisms that elicit this lineage plasticity, and the importance in health and disease, remain unclear. In this study we show that iILC2 are potent inducers of airway inflammation in response to acute house dust mite challenge. We find that Notch signaling induces lineage plasticity of mature ILC2 and drives the conversion of nILC2 into iILC2. Acute blockade of Notch signaling abolished functional iILC2, but not nILC2, in vivo. Exposure of isolated nILC2 to Notch ligands induced Rorc expression and elicited dual IL-13/IL-17 production, converting nILC2 into iILC2. Together these results reveal a novel role for Notch signaling in eliciting ILC2 plasticity and driving the emergence of highly proinflammatory innate lymphocytes.


Asunto(s)
Inmunidad Innata , Linfocitos/metabolismo , Receptores Notch/metabolismo , Transducción de Señal , Animales , Linaje de la Célula , Citocinas/inmunología , Inflamación/inmunología , Interleucina-13/inmunología , Interleucina-17/inmunología , Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Pyroglyphidae/inmunología
12.
Opt Express ; 26(3): 2569-2583, 2018 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-29401795

RESUMEN

We demonstrate advanced transversal radio frequency (RF) and microwave functions based on a Kerr optical comb source generated by an integrated micro-ring resonator. We achieve extremely high performance for an optical true time delay aimed at tunable phased array antenna applications, as well as reconfigurable microwave photonic filters. Our results agree well with theory. We show that our true time delay would yield a phased array antenna with features that include high angular resolution and a wide range of beam steering angles, while the microwave photonic filters feature high Q factors, wideband tunability, and highly reconfigurable filtering shapes. These results show that our approach is a competitive solution to implementing reconfigurable, high performance and potentially low cost RF and microwave signal processing functions for applications including radar and communication systems.

13.
Biochem J ; 473(1): 7-19, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26450924

RESUMEN

Dendritic cells (DCs) and invariant natural killer T (iNKT) cells play important roles in linking innate immunity and adaptive immunity. Mature DCs activated by Toll-like receptor (TLR) agonists directly activate iNKT cells and the iNKT ligand α-galactosylceramide (α-Galcer) can induce DC maturation, resulting in enhanced protective immune responses. In the present study, we aimed to boost anti-tumour immunity in a murine colon cancer model by synergizing DCs and iNKT cells using α-Galcer-loaded tumour cells (tumour-Gal) and the TLR9 agonist cytosine-phosphorothioate-guanine (CpG1826). The vaccine strategy was sufficient to inhibit growth of established tumours and prolonged survival of tumour-bearing mice. Importantly, the immunization induced an adaptive memory immune response as the survivors from primary tumour inoculations were resistant to a tumour re-challenge. Furthermore, injection of tumour-Gal with CpG1826 resulted in iNKT cell activation and DC maturation as defined by interferon (IFN)-γ secretion by iNKT, natural killer (NK) cells and interleukin (IL)-12 by DCs. Immunohistochemistry analysis revealed that cluster of differentiation (CD)4(+) T-cells and CD8(+) T-cells played important roles in anti-tumour immunity. Additionally, the vaccine redirected Th2 (T-helper cell type 2) responses toward Th1 (T-helper cell type 1) responses with increases in IL-2, IFN-γ expression and decreases in IL-4 and IL-5 expression after immunization with tumour-Gal with CpG1826. Taken together, our results demonstrated a novel vaccination by synergizing tumour-Gal and CpG1826 against murine colon cancer, which can be further developed as tumour-specific immunotherapy against human cancer.


Asunto(s)
Antineoplásicos/administración & dosificación , Vacunas contra el Cáncer/administración & dosificación , Neoplasias del Colon/prevención & control , Modelos Animales de Enfermedad , Galactosilceramidas/administración & dosificación , Receptor Toll-Like 9/agonistas , Animales , Técnicas de Cocultivo , Neoplasias del Colon/patología , Femenino , Ratones , Ratones Endogámicos C57BL , Resultado del Tratamiento , Células Tumorales Cultivadas
14.
Opt Express ; 23(23): 30014-9, 2015 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-26698482

RESUMEN

An ultraflat self-oscillating optical frequency comb generator based on an optoelectronic oscillator employing cascaded modulators was proposed and experimentally demonstrated. By incorporating the optoelectronic oscillation loop with cascaded modulators into the optical frequency comb generator, 11 ultraflat comb lines would be generated, and the frequency spacing is equal to the oscillation frequency of the OEO. 10 and 12GHz optical frequency combs are demonstrated with the spectral power variation below 0.82dB and 0.93dB respectively. The corresponding spectral pure microwave source are also generated and evaluated. The corresponding single-sideband phase noise are as low as -122dBc/Hz and -115 dBc/Hz at 10 kHz offset frequency.

15.
Opt Lett ; 40(24): 5858-61, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26670530

RESUMEN

In this Letter, we propose and experimentally demonstrate a novel broadband and wide-range feedback tuning scheme for phase-locked loop (PLL) stabilization of tunable optoelectronic oscillators (OEO). The proposed scheme was realized in a simple and feasible way based on a dual-parallel Mach-Zehnder modulator (DPMZM) and optical bandpass filter (OBPF). The wide RF phase-shift range and broadband performance of the proposed scheme were demonstrated theoretically and experimentally, which ensured OEO's wide operating temperature range and tunability in PLL stabilization. As a result, PLL stabilization for OEO was achieved at different oscillating frequencies and the long-term stability was greatly improved without any thermal control. The measured overlapping Allan deviation of PLL-locked OEO reached lower than 10⁻¹° after 1000-s averaging time, which was four orders of magnitude better than the free-running OEO. The phase noise performance was also improved at low-offset frequencies and remained the same at high-offset frequencies.

16.
Sci Total Environ ; 947: 174650, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38986701

RESUMEN

The escalating health risks posed by warm weather in urban areas have become a pressing global public health issue. This study undertakes a meta-analysis to evaluate the impact of warm weather on health in urban settings. We comprehensively searched PubMed, Embase, Scopus, and Web of Science for literature published before September 6, 2023, evaluating evidence quality using the Navigation Guide Criteria. We included original studies utilizing high temperatures or heatwaves as exposure metrics and employing observational designs. A meta-analysis was carried out to assess the relative risk (RR) of the association between high temperatures (or heatwaves) and disease outcomes. Out of 12,893 studies identified, 188 met the inclusion criteria for meta-analysis. Results demonstrate a statistically significant association between a 1 °C temperature increase and a 2.1 % elevation in disease-related mortality (RR 1.021 [95 % CI 1.018-1.023]), alongside a 1.1 % increase in morbidity (RR 1.011 [95 % CI 1.007-1.016]). Heatwaves also showed associations with increased total mortality (RR 1.224 [95 % CI 1.186-1.264]) and morbidity (RR 1.038 [95 % CI 1.010-1.066]). Subgroup analyses for diseases, sex, age, climatic zones, countries, and time periods consistently indicated heightened disease-related mortality and morbidity linked to high temperatures. Notably, China's urban population faced an elevated mortality risk (RR 1.027 [95 % CI 1.018-1.036]) compared to other countries (RR 1.021 [95 % CI 1.019-1.024]). Mortality associated with high temperatures after 2007 (RR 1.022 [95 % CI 1.015-1.029]) was higher than before 2007 (RR 1.017 [95 % CI 1.013-1.021]), reflecting increased health risks as the global warming accelerates. Our findings underscore the positive association between rising temperatures and/or heatwaves and adverse health outcomes in urban populations. The widespread exposure to high temperatures amplifies health risks across various diseases, demographics, climates, and countries, with potential exacerbation under ongoing global warming. Further research is imperative to delineate factors influencing altered heat exposure impacts.


Asunto(s)
Calor , Salud Urbana , Humanos , Salud Urbana/estadística & datos numéricos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Cambio Climático
17.
ACS Nano ; 18(28): 18129-18150, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38954632

RESUMEN

The advent of catheter-based minimally invasive surgical instruments has provided an effective means of diagnosing and treating human disease. However, conventional medical catheter devices are limited in functionalities, hindering their ability to gather tissue information or perform precise treatment during surgery. Recently, electronic catheters have integrated various sensing and therapeutic technologies through micro/nanoelectronics, expanding their capabilities. As micro/nanoelectronic devices become more miniaturized, flexible, and stable, electronic surgical catheters are evolving from simple tools to multiplexed sensing and theranostics for surgical applications. The review on multifunctional electronic surgical catheters is lacking and thus is not conducive to the reader's comprehensive understanding of the development trend in this field. This review covers the advances in multifunctional electronic catheters for precise and intelligent diagnosis and therapy in minimally invasive surgery. It starts with the summary of clinical minimally invasive surgical instruments, followed by the background of current clinical catheter devices for sensing and therapeutic applications. Next, intelligent electronic catheters with integrated electronic components are reviewed in terms of electronic catheters for diagnosis, therapy, and multifunctional applications. It highlights the present status and development potential of catheter-based minimally invasive surgical devices, while also illustrating several significant challenges that remain to be overcome.


Asunto(s)
Catéteres , Procedimientos Quirúrgicos Mínimamente Invasivos , Humanos , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación
18.
Microsyst Nanoeng ; 10: 72, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38828404

RESUMEN

The collection of multiple-channel electrophysiological signals enables a comprehensive understanding of the spatial distribution and temporal features of electrophysiological activities. This approach can help to distinguish the traits and patterns of different ailments to enhance diagnostic accuracy. Microneedle array electrodes, which can penetrate skin without pain, can lessen the impedance between the electrodes and skin; however, current microneedle methods are limited to single channels and cannot achieve multichannel collection in small areas. Here, a multichannel (32 channels) microneedle dry electrode patch device was developed via a dimensionality reduction fabrication and integration approach and supported by a self-developed circuit system to record weak electrophysiological signals, including electroencephalography (EEG), electrocardiogram (ECG), and electromyography (EMG) signals. The microneedles reduced the electrode-skin contact impedance by penetrating the nonconducting stratum corneum in a painless way. The multichannel microneedle array (MMA) enabled painless transdermal recording of multichannel electrophysiological signals from the subcutaneous space, with high temporal and spatial resolution, reaching the level of a single microneedle in terms of signal precision. The MMA demonstrated the detection of the spatial distribution of ECG, EMG and EEG signals in live rabbit models, and the microneedle electrode (MNE) achieved better signal quality in the transcutaneous detection of EEG signals than did the conventional flat dry electrode array. This work offers a promising opportunity to develop advanced tools for neural interface technology and electrophysiological recording.

19.
Adv Mater ; 36(18): e2311524, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38275007

RESUMEN

Neuromorphic visual sensors (NVS) based on photonic synapses hold a significant promise to emulate the human visual system. However, current photonic synapses rely on exquisite engineering of the complex heterogeneous interface to realize learning and memory functions, resulting in high fabrication cost, reduced reliability, high energy consumption and uncompact architecture, severely limiting the up-scaled manufacture, and on-chip integration. Here a photo-memory fundamental based on ion-exciton coupling is innovated to simplify synaptic structure and minimize energy consumption. Due to the intrinsic organic/inorganic interface within the crystal, the photodetector based on monolithic 2D perovskite exhibits a persistent photocurrent lasting about 90 s, enabling versatile synaptic functions. The electrical power consumption per synaptic event is estimated to be≈1.45 × 10-16 J, one order of magnitude lower than that in a natural biological system. Proof-of-concept image preprocessing using the neuromorphic vision sensors enabled by photonic synapse demonstrates 4 times enhancement of classification accuracy. Furthermore, getting rid of the artificial neural network, an expectation-based thresholding model is put forward to mimic the human visual system for facial recognition. This conceptual device unveils a new mechanism to simplify synaptic structure, promising the transformation of the NVS and fostering the emergence of next generation neural networks.


Asunto(s)
Compuestos de Calcio , Redes Neurales de la Computación , Óxidos , Sinapsis , Titanio , Óxidos/química , Titanio/química , Sinapsis/fisiología , Compuestos de Calcio/química , Humanos , Fotones , Visión Ocular/fisiología
20.
Biosensors (Basel) ; 14(7)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-39056604

RESUMEN

Dopamine (DA), ascorbic acid (AA), and uric acid (UA) are crucial neurochemicals, and their abnormal levels are involved in various neurological disorders. While electrodes for their detection have been developed, achieving the sensitivity required for in vivo applications remains a challenge. In this study, we proposed a synthetic Au24Cd nanoenzyme (ACNE) that significantly enhanced the electrochemical performance of metal electrodes. ACNE-modified electrodes demonstrated a remarkable 10-fold reduction in impedance compared to silver microelectrodes. Furthermore, we validated their excellent electrocatalytic activity and sensitivity using five electrochemical detection methods, including cyclic voltammetry, differential pulse voltammetry, square-wave pulse voltammetry, normal pulse voltammetry, and linear scanning voltammetry. Importantly, the stability of gold microelectrodes (Au MEs) modified with ACNEs was significantly improved, exhibiting a 30-fold enhancement compared to Au MEs. This improved performance suggests that ACNE functionalization holds great promise for developing micro-biosensors with enhanced sensitivity and stability for detecting small molecules.


Asunto(s)
Ácido Ascórbico , Técnicas Biosensibles , Dopamina , Técnicas Electroquímicas , Oro , Microelectrodos , Ácido Úrico , Dopamina/análisis , Oro/química , Ácido Ascórbico/análisis , Ácido Úrico/análisis , Plata/química , Cadmio/análisis
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