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1.
Anal Chem ; 96(12): 4835-4844, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38488022

RESUMO

The rapid proliferation of new psychoactive substances (NPS) poses significant challenges to conventional mass-spectrometry-based identification methods due to the absence of reference spectra for these emerging substances. This paper introduces PS2MS, an AI-powered predictive system designed specifically to address the limitations of identifying the emergence of unidentified novel illicit drugs. PS2MS builds a synthetic NPS database by enumerating feasible derivatives of known substances and uses deep learning to generate mass spectra and chemical fingerprints. When the mass spectrum of an analyte does not match any known reference, PS2MS simultaneously examines the chemical fingerprint and mass spectrum against the putative NPS database using integrated metrics to deduce possible identities. Experimental results affirm the effectiveness of PS2MS in identifying cathinone derivatives within real evidence specimens, signifying its potential for practical use in identifying emerging drugs of abuse for researchers and forensic experts.


Assuntos
Aprendizado Profundo , Drogas Ilícitas , Cromatografia Líquida/métodos , Psicotrópicos/análise , Espectrometria de Massas/métodos , Drogas Ilícitas/análise , Detecção do Abuso de Substâncias/métodos
2.
Int Arch Allergy Immunol ; 185(1): 20-32, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37729893

RESUMO

INTRODUCTION: Sexual dysfunction (SD) and allergic disease are common health concerns worldwide and bear a potential relationship. This scoping review is conducted to analyze the currently available data regarding the associations between these two health issues. METHODS: A comprehensive literature search was performed in the databases of PubMed, MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science to retrieve studies that were published before January 2023. A narrative synthesis was conducted to analyze the effects of allergic diseases on SD based on the evaluation of the Female Sexual Function Index (FSFI) and International Index of Erectile Function (IIEF). RESULTS: Twelve observational studies were included after the selection process. The results generally suggested lower FSFI or IIEF scores in patients with asthma, allergic rhinitis, allergic rhinoconjunctivitis, and urticaria compared to the healthy control groups. The underlying factors of this relationship could be inflammation, psychological factors, hormonal changes, sleep disorders, sexual behavior-related allergic reactions, social economic status, and the use of medications. CONCLUSION: SD and allergic disease are interrelated based on the extant literature. This scoping review provides insights into the clinical implications of both entities, while more research studies are warranted to further elucidate this complex relationship.


Assuntos
Asma , Rinite Alérgica , Masculino , Humanos , Feminino , Rinite Alérgica/epidemiologia , Inflamação
3.
Am J Clin Dermatol ; 25(2): 261-280, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38159214

RESUMO

Skin perceives and reacts to external mechanical forces to create resistance against the external environment. Excessive or inappropriate stimuli of pressure may lead to cellular alterations of the skin and the development of both benign and malignant skin disorders. We conducted a comprehensive literature review to delve into the pressure-induced and aggravated skin disorders and their underlying pressure-related mechanisms. Dysregulated mechanical responses of the skin give rise to local inflammation, ischemia, necrosis, proliferation, hyperkeratosis, impaired regeneration, atrophy, or other injurious reactions, resulting in various disease entities. The use of personal devices, activities, occupations, weight bearing, and even unintentional object contact and postures are potential scenarios that account for the development of pressure-related skin disorders. The spectrum of these skin disorders may involve the epidermis (keratinocytes and melanocytes), hair follicles, eccrine glands, nail apparatuses, dermis (fibroblasts, mast cells, and vasculature), subcutis, and fascia. Clarifying the clinical context of each patient and recognizing how pressure at the cellular and tissue levels leads to skin lesions can enhance our comprehension of pressure-related skin disorders to attain better management.


Assuntos
Dermatopatias , Pele , Humanos , Pele/patologia , Epiderme/patologia , Queratinócitos/patologia , Dermatopatias/etiologia , Dermatopatias/patologia , Folículo Piloso
4.
Int J Mol Sci ; 24(20)2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37894888

RESUMO

Since human skin is the primary interface responding to external mechanical stimuli, extrinsic forces can disrupt its balanced microenvironment and lead to cutaneous lesions. We performed this review to delve into the pathological effects of mechanical pressure on skin from the cellular perspective. Fibroblasts of different subsets act as heterogeneous responders to mechanical load and express diverse functionalities. Keratinocytes relay mechanical signals through mechanosensitive receptors and the ensuing neurochemical cascades to work collaboratively with other cells and molecules in response to pressure. Mast cells release cytokines and neuropeptides, promoting inflammation and facilitating interaction with sensory neurons, while melanocytes can be regulated by pressure through cellular and molecular crosstalk. Adipocytes and stem cells sense pressure to fine-tune their regulations of mechanical homeostasis and cell differentiation. Applying mechanical pressure to the skin can induce various changes in its microenvironment that potentially lead to pathological alterations, such as ischemia, chronic inflammation, proliferation, regeneration, degeneration, necrosis, and impaired differentiation. The heterogeneity of each cellular lineage and subset from different individuals with various underlying skin conditions must be taken into consideration when discussing the pathological effects of pressure on the skin. Thus, elucidating the mechanotransduction and mechanoresponsive pathways from the cellular viewpoint is crucial in diagnosing and managing relevant dermatological disorders.


Assuntos
Mecanotransdução Celular , Pele , Humanos , Pele/patologia , Queratinócitos/metabolismo , Melanócitos/metabolismo , Inflamação/metabolismo
5.
Biomedicines ; 11(2)2023 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-36831157

RESUMO

Obstructive sleep apnea (OSA) has been associated with cognitive decline via several mechanisms, including intermittent hypoxemia, sleep fragmentation, and neuroinflammation. The neurological consequences of OSA have evolved into a major biopsychosocial concern in the elderly, especially memory impairment. We aimed to identify the polysomnographic (PSG) parameters capable of predicting memory impairment among OSA patients at or over age 50 with OSA. We reviewed the 10-year electronic medical records of OSA patients and compared the initial PSG parameters between those presenting and not presenting self-reported memory impairment. We conducted subgroup analyses based on OSA severity and performed multivariate analysis to correlate PSG parameters with memory impairment. The result showed that 25 out of the 156 (16%) investigated patients experienced self-reported memory impairment during follow-up. As compared to OSA patients without self-reported memory impairment, those reported with self-reported memory impairment had a higher oxygen desaturation index (ODI) (23.9 ± 17.8 versus 18.2 ± 12.0, p = 0.048). Regarding the associations between apnea-hypopnea index (AHI) as well as ODI and self-reported memory impairment among OSA subgroups classified by severity, the associations were only evident in the severe OSA subgroup in both univariate (p < 0.001; p = 0.005) and multivariate analyses (p = 0.014; p = 0.018). We concluded that AHI and ODI are the most relevant PSG parameters in predicting memory impairment in severe OSA patients.

6.
Sci Rep ; 12(1): 22308, 2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36566268

RESUMO

A dynamical control of the coupling strengths between dressed states and probe photon states is demonstrated with a transmon-like artificial atom coupled to two closely spaced resonant modes. When the atom is driven with one mode, the atom state and driving photon states form the so-called dressed states. Dressed states with sideband index up to 3 were prepared and probed via the strong coupling to the other resonant mode. Spectroscopy reveals that the coupling strengths are "dressed" and can be modulated by the power and sideband index of the driving. The transmission of the probe tone is modulated by the driving microwave amplitude with a Bessel behavior, displaying multi-photon process associated with the inter-atomic level transitions.

7.
Rev Sci Instrum ; 93(8): 084501, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050105

RESUMO

We report on a holoscope axion search experiment near 19.6 µeV from the Taiwan Axion Search Experiment with Haloscope collaboration. This experiment is carried out via a frequency-tunable cavity detector with a volume V = 0.234 liter in a magnetic field B0 = 8 T. With a signal receiver that has a system noise temperature Tsys ≅ 2.2 K and an experiment time of about one month, the search excludes values of the axion-photon coupling constant gaγγ ≳ 8.1 × 10-14 GeV-1, a factor of 11 above the Kim-Shifman-Vainshtein-Zakharov benchmark model, at the 95% confidence level in the mass range of 19.4687-19.8436 µeV. We present the experimental setup and procedures to accomplish this search.

8.
Phys Rev Lett ; 129(11): 111802, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36154404

RESUMO

This Letter reports on the first results from the Taiwan Axion Search Experiment with a Haloscope, a search for axions using a microwave cavity at frequencies between 4.707 50 and 4.798 15 GHz. Apart from the nonaxion signals, no candidates with a significance of more than 3.355 were found. The experiment excludes models with the axion-two-photon coupling |g_{aγγ}|≳8.1×10^{-14} GeV^{-1}, a factor of eleven above the benchmark Kim-Shifman-Vainshtein-Zakharov model, in the mass range 19.4687

9.
Sci Rep ; 11(1): 14491, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262095

RESUMO

We have studied carefully the behaviors of entangled qubits on the IBM Rochester with various connectivities and under a "noisy" environment. A phase trajectory analysis based on our measurements of the GHZ-like states is performed. Our results point to an important fact that entangled qubits are "protected" against environmental noise by a scaling property that impacts only the weighting of their amplitudes. The reproducibility of most measurements has been confirmed within a reasonably short gate operation time. But there still are a few combinations of qubits that show significant entanglement evolution in the form of transitions between quantum states. The phase trajectory of an entangled evolution, and the impact of the sudden death of GHZ-like states and the revival of newly excited states are analyzed in details. All observed trajectories of entangled qubits arise under the influences of the newly excited states in a "noisy" intermediate-scale quantum (NISQ) computer.

10.
Micromachines (Basel) ; 11(5)2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32429169

RESUMO

Physical unclonable function (PUF), a hardware-efficient approach, has drawn a lot ofattention in the security research community for exploiting the inevitable manufacturing variabilityof integrated circuits (IC) as the unique fingerprint of each IC. However, analog PUF is notrobust and resistant to environmental conditions. In this paper, we propose a digital PUF-basedsecure authentication model using the emergent spin-transfer torque magnetic random-accessmemory (STT-MRAM) PUF (called STT-DPSA for short). STT-DPSA is an original secure identityauthentication architecture for Internet of Things (IoT) devices to devise a computationallylightweight authentication architecture which is not susceptible to environmental conditions.Considering hardware security level or cell area, we alternatively build matrix multiplication orstochastic logic operation for our authentication model. To prove the feasibility of our model, thereliability of our PUF is validated via the working windows between temperature interval (-35 °C,110 °C) and Vdd interval [0.95 V, 1.16 V] and STT-DPSA is implemented with parameters n = 32,i = o = 1024, k = 8, and l = 2 using FPGA design flow. Under this setting of parameters, an attackerneeds to take time complexity O(2256) to compromise STT-DPSA. We also evaluate STT-DPSA usingSynopsys design compiler with TSMC 0.18 um process.

11.
Opt Express ; 27(25): 36088-36099, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31873395

RESUMO

We experimentally study interactions between two microwave fields mediated by 3-level transmon artificial atom with two-photon processes. The transmon has good selection rule, preventing one-photon transition, but allowing two-photon transition from ground state(0) to 2nd excited state(2). By pumping a control tone in resonance to the transition between 1st(1) and 2nd excited state(2), we control the one-photon transparency for 0 to 1 transition and two-photon transparency for 0 to 2 transition. The results are explained by the Autler-Townes splitting induced by the control microwave. In addition, two possible microwave amplification processes involving two-photon processes are also studied. The 4-wave mixing scheme increases the transmission by 3% while 2-photon optical pumping produces a 11% narrowband increment. All these phenomena can be operated with control and probe tones in a narrow band.

12.
ACS Sens ; 4(9): 2546-2552, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31456397

RESUMO

SnSe2 is an anisotropic binary-layered material with rich physics, which could see it used for a variety of potential applications. Here, we investigate the gas-sensing properties of SnSe2 using first-principles calculations and verify predictions using a gas sensor made of few-layer SnSe2 grown by chemical vapor deposition. Theoretical simulations indicate that electrons transfer from SnSe2 to NO2, whereas the direction of charge transfer is the opposite for NH3. Notably, a flat molecular band appears around the Fermi energy after NO2 adsorption and the induced molecular band is close to the conduction band minimum. Moreover, compared with NH3, NO2 molecules adsorbed on SnSe2 have a lower adsorption energy and a higher charge transfer value. The dynamic-sensing responses of SnSe2 sensors confirm the theoretical predictions. The good match between the theoretical prediction and experimental demonstration suggests that the underlying sensing mechanism is related to the charge transfer and induced flat band. Our results provide a guideline for designing high-performance gas sensors based on SnSe2.


Assuntos
Técnicas de Química Analítica/instrumentação , Gases/análise , Limite de Detecção , Compostos de Estanho/química , Transporte de Elétrons , Modelos Moleculares , Conformação Molecular
13.
J Parallel Distrib Comput ; 122: 36-50, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30872894

RESUMO

Bayesian Sequential Partitioning (BSP) is a statistically effective density estimation method to comprehend the characteristics of a high dimensional data space. The intensive computation of the statistical model and the counting of enormous data have caused serious design challenges for BSP to handle the growing volume of the data. This paper proposes a high performance design of BSP by leveraging a heterogeneous CPU/GPGPU system that consists of a host CPU and a K80 GPGPU. A series of techniques, on both data structures and execution management policies, is implemented to extensively exploit the computation capability of the heterogeneous many-core system and alleviate system bottlenecks. When compared with a parallel design on a high-end CPU, the proposed techniques achieve 48x average runtime enhancement while the maximum speedup can reach 78.76x.

14.
Opt Express ; 25(24): 30395-30405, 2017 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-29221069

RESUMO

We experimentally studied the coupling between a double split ring resonator and a complementary split ring resonator. The greatest coupling occurs when the two resonators are separated by the average ring radius, and the dimensionless coupling is as large as 0.1, allowing a novel planar metamaterial based on this hybrid structure. The coupling strength can be varied up to a factor of 2 by changing the relative orientation of the split ring resonators. A 2×2 waveguide structure with -10 dB coupling factor can be achieved, and showing multi-mode plasmon-induced transparency. It can be considered one-dimensional metamaterials exhibiting negative permeability and permittivity simultaneously.

15.
J Microbiol Biotechnol ; 24(9): 1245-53, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24851812

RESUMO

One-step sulfuric acid saccharification of the red alga Pterocladiella capillacea was optimized, and various detoxification methods (neutralization, overliming, and electrodialysis) of the acid hydrolysate were evaluated for fermentation with the thermotolerant yeast Kluyveromyces marxianus. A proximate composition analysis indicated that P. capillacea was rich in carbohydrates. A significant galactose recovery of 81.1 ± 5% was also achieved under the conditions of a 12% (w/v) biomass load, 5% (v/v) sulfuric acid, 121°C, and hydrolysis for 30 min. Among the various detoxification methods, electrodialysis was identified as the most suitable for fermentable sugar recovery and organic acid removal (100% reduction of formic and levulinic acids), even though it failed to reduce the amount of the inhibitor 5-HMF. As a result, K. marxianus fermentation with the electrodialyzed acid hydrolysate of P. capillacea resulted in the best ethanol levels and fermentation efficiency.


Assuntos
Biocombustíveis , Biomassa , Etanol/metabolismo , Kluyveromyces/metabolismo , Rodófitas/química , Ácidos Sulfúricos/química , Reatores Biológicos , Etanol/análise , Fermentação , Formiatos/metabolismo , Furaldeído/análogos & derivados , Furaldeído/metabolismo , Hidrólise , Ácidos Levulínicos/metabolismo
16.
Appl Opt ; 45(3): 501-10, 2006 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-16463735

RESUMO

An imaging system that combines synthetic-aperture imaging, holography, and an optical chirp with confocal imaging is described and analyzed. Comparisons are made with synthetic-aperture radar systems. Adaptation of several synthetic-aperture radar techniques to the optical counterparts is suggested.

17.
Appl Opt ; 43(23): 4512-9, 2004 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-15376427

RESUMO

It has long been known that image plane holography with low-coherence illumination achieves optical sectioning of a volume object. A method is analyzed that is similar to image plane holography, but the interferometric arrangement utilizes the interference between two object-bearing beams instead of the basic object and reference beams.

18.
J Opt Soc Am A Opt Image Sci Vis ; 20(2): 380-7, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12570305

RESUMO

A theory of optical sectioning by image plane holography is developed, emphasizing the use of broad-spectrum holographic methods to enhance the process. It is shown that a broad-spectrum source in a grating interferometer imitates the behavior of a monochromatic broad source.

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