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1.
Sensors (Basel) ; 23(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38139652

RESUMO

The explosive demand for wireless communications has intensified the complexity of spectrum dynamics, particularly within unlicensed bands. To promote efficient spectrum utilization and minimize interference during communication, spectrum sensing needs to evolve to a stage capable of detecting multidimensional spectrum states. Signal identification, which identifies each device's signal source, is a potent method for deriving the spectrum usage characteristics of wireless devices. However, most existing signal identification methods mainly focus on signal classification or modulation classification, thus offering limited spectrum information. In this paper, we propose DSINet, a multitask learning-based deep signal identification network for advanced spectrum sensing systems. DSINet addresses the deep signal identification problem, which involves not only classifying signals but also deriving the spectrum usage characteristics of signals across various spectrum dimensions, including time, frequency, power, and code. Comparative analyses reveal that DSINet outperforms existing shallow signal identification models, with performance improvements of 3.3% for signal classification, 3.3% for hall detection, and 5.7% for modulation classification. In addition, DSINet solves four different tasks with a 65.5% smaller model size and 230% improved computational performance compared to single-task learning model sets, providing meaningful results in terms of practical use.

2.
Sensors (Basel) ; 23(13)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37447708

RESUMO

Global navigation satellite systems (GNSSs) provide a common positioning method that utilizes satellite signals to determine the spatial location of a receiver. However, there are several error factors in standalone GNSS positioning due to instrumental, procedural, and environmental factors that arise during the signal transmission process, and the final positioning error can be up to several meters or greater in length. Thus, real-time kinematic (RTK) correction and post-mission precise point positioning (PPP) processing technologies are proposed to improve accuracy and accomplish precise position measurements. To evaluate the geolocation accuracy of mosaicked UAV images of an abandoned mine site, we compared each orthomosaic image and digital elevation model obtained using standalone GNSS positioning, differential (RTK) GNSS positioning, and post-mission PPP processing techniques. In the three types of error evaluation measure (i.e., relative camera location error, ground control points-based absolute image mapping error, and volumetric difference of mine tailings), we found that the RTK GNSS positioning method obtained the best performance in terms of the relative camera location error and the absolute image mapping error evaluations, and the PPP post-processing correction effectively reduced the error (69.5% of the average total relative camera location error and 59.3% of the average total absolute image mapping error) relative to the standalone GNSS positioning method. Although differential (RTK) GNSS positioning is widely used in positioning applications that require very high accuracy, post-mission PPP processing can also be used in various fields in which it is either not feasible to operate expensive equipment to receive RTK GNSS signals or network RTK services are unavailable.


Assuntos
Tecnologia , Fenômenos Biomecânicos
3.
ACS Appl Mater Interfaces ; 14(49): 54550-54557, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36448483

RESUMO

Human respiratory aerosols contain diverse potential biomarkers for early disease diagnosis. Here, we report the direct and label-free detection of SARS-CoV-2 in respiratory aerosols using a highly adsorptive Au-TiO2 nanocomposite SERS face mask and an ablation-assisted autoencoder. The Au-TiO2 SERS face mask continuously preconcentrates and efficiently captures the oronasal aerosols, which substantially enhances the SERS signal intensities by 47% compared to simple Au nanoislands. The ultrasensitive Au-TiO2 nanocomposites also demonstrate the successful detection of SARS-CoV-2 spike proteins in artificial respiratory aerosols at a 100 pM concentration level. The deep learning-based autoencoder, followed by the partial ablation of nondiscriminant SERS features of spike proteins, allows a quantitative assay of the 101-104 pfu/mL SARS-CoV-2 lysates (comparable to 19-29 PCR cyclic threshold from COVID-19 patients) in aerosols with an accuracy of over 98%. The Au-TiO2 SERS face mask provides a platform for breath biopsy for the detection of various biomarkers in respiratory aerosols.


Assuntos
COVID-19 , Nanocompostos , Humanos , Ouro , Análise Espectral Raman , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Máscaras , COVID-19/diagnóstico , Aerossóis e Gotículas Respiratórios , Aprendizado de Máquina , Biomarcadores
4.
ACS Omega ; 7(17): 15174-15185, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35572752

RESUMO

Despite various strategies to address sticking failure in stainless steels (STSs), difficulties in understanding its fundamental mechanisms hinder precise solutions during STS fabrication. This study investigated the effect of chromium (Cr) content on the microstructures and failure modes of oxide scales under a tensile load, simulating the hot-rolling process. The dynamic, real-time behavior of crack initiation, propagation, and interfacial delamination in the oxide scales under tension was analyzed using an in situ scanning electron microscopy (SEM) tensile test. With a high Cr content, iron (Fe) oxide and chromium(III) oxide (Cr2O3) form a layered structure, which is delaminated along the interfaces between the thin Cr2O3 layer and the bulk after perpendicular cracking. The saturated crack densities obtained from in situ SEM provide interfacial strength, while the elastic modulus and hardness obtained from nanoindentation provide vertical fracture strength. In combination with an ex situ elemental image analysis, the in situ SEM results reveal three different failure modes of the four different STSs. The results confirm that sticking failure is more likely to occur as the Cr content increases.

5.
Can J Vet Res ; 83(4): 248-254, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31571723

RESUMO

The objective of the present study was to evaluate the efficacy of a commercial porcine reproductive and respiratory syndrome virus (PRRSV) subunit vaccine against heterologous PRRSV-1 and PRRSV-2 challenge in late-term pregnant gilts. Gilts were vaccinated intramuscularly 56 and 35 days antepartum (on days 58 and 79 of gestation) and challenged intranasally 21 days antepartum (on day 93 of gestation) with PRRSV-1 or PRRSV-2. Regardless of the challenge strain's genotype, the vaccinated gilts carried their pregnancies to term and farrowed between days 114 and 115 of gestation. All the unvaccinated gilts aborted, between days 105 and 110 of gestation. The vaccinated gilts had a significantly lower level (P < 0.05) of PRRSV viremia and significantly higher levels (P < 0.05) of virus-neutralizing antibodies and interferon-γ-secreting cells compared with the unvaccinated gilts. The mean number of PRRSV-positive cells per area of fetal tissue examined did not differ significantly between the litters from the vaccinated and unvaccinated gilts. The data presented here indicate that vaccination in late-term pregnancy with PRRSV subunit vaccine is efficacious against reproductive failure due to heterologous PRRSV-1 and PRRSV-2 infection.


L'objectif de la présente étude était d'évaluer l'efficacité d'un vaccin sous-unitaire commercial contre le virus du syndrome reproducteur et respiratoire porcin (VSRRP) lors d'une infection défi avec des souches de VSRRP-1 et VSRRP-2 hétérologues chez des cochettes en fin de gestation. Les cochettes furent vaccinées par voie intramusculaire 56 et 35 jours ante-partum (aux jours 58 et 79 de la gestation) et infectées par voie intra-nasale 21 jours ante-partum (jour 93 de la gestation) avec VSRRP-1 ou VSRRP-2. Sans égard au génotype de la souche utilisée pour l'infection défi, les cochettes vaccinées ont mené leur gestation à terme et ont mis-bas entre les jours 114 et 115 de la gestation. Toutes les cochettes non-vaccinées ont avorté, entre les jours 105 et 110 de gestation. Les cochettes vaccinées avaient un niveau significativement plus faible (P < 0,05) de virémie à VSRRP et des niveaux significativement plus élevés (P < 0,05) d'anticorps viraux neutralisants et de cellules secrétant de l'interféron-γ comparativement aux cochettes non-vaccinées. Le nombre moyen de cellules positives pour VSRRP par surface de tissu foetal examiné ne différait pas significativement entre les portées des cochettes vaccinées et non-vaccinées. Les résultats présentés ici indiquent que la vaccination en fin de gestation avec un vaccin sous-unitaire anti-VSRRP est efficace contre les problèmes reproducteurs causés par une infection par des souches hétérologues de VSRRP-1 et VSRRP-2.(Traduit par Docteur Serge Messier).


Assuntos
Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Complicações Infecciosas na Gravidez/veterinária , Vacinas Virais/imunologia , Animais , Feminino , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Subunidades Proteicas , Suínos , Vacinas de Subunidades Antigênicas/imunologia , Proteínas Virais/imunologia
6.
Sensors (Basel) ; 19(9)2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31052195

RESUMO

A fire detection system requires accurate and fast mechanisms to make the right decision in a fire situation. Since most commercial fire detection systems use a simple sensor, their fire recognition accuracy is deficient because of the limitations of the detection capability of the sensor. Existing proposals, which use rule-based algorithms or image-based machine learning can hardly adapt to the changes in the environment because of their static features. Since the legacy fire detection systems and network services do not guarantee data transfer latency, the required need for promptness is unmet. In this paper, we propose a new fire detection system with a multifunctional artificial intelligence framework and a data transfer delay minimization mechanism for the safety of smart cities. The framework includes a set of multiple machine learning algorithms and an adaptive fuzzy algorithm. In addition, Direct-MQTT based on SDN is introduced to solve the traffic concentration problems of the traditional MQTT. We verify the performance of the proposed system in terms of accuracy and delay time and found a fire detection accuracy of over 95%. The end-to-end delay, which comprises the transfer and decision delays, is reduced by an average of 72%.

7.
ACS Nano ; 13(6): 6531-6539, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31072094

RESUMO

Both self-healable conductors and stretchable conductors have been previously reported. However, it is still difficult to simultaneously achieve high stretchability, high conductivity, and self-healability. Here, we observed an intriguing phenomenon, termed "electrical self-boosting", which enables reconstructing of electrically percolative pathways in an ultrastretchable and self-healable nanocomposite conductor (over 1700% strain). The autonomously reconstructed percolative pathways were directly verified by using microcomputed tomography and in situ scanning electron microscopy. The encapsulated nanocomposite conductor shows exceptional conductivity (average value: 2578 S cm-1; highest value: 3086 S cm-1) at 3500% tensile strain by virtue of efficient strain energy dissipation of the self-healing polymer and self-alignment and rearrangement of silver flakes surrounded by spontaneously formed silver nanoparticles and their self-assembly in the strained self-healing polymer matrix. In addition, the conductor maintains high conductivity and stretchability even after recovered from a complete cut. Besides, a design of double-layered conductor enabled by the self-bonding assembly allowed a conducting interface to be located on the neutral mechanical plane, showing extremely durable operations in a cyclic stretching test. Finally, we successfully demonstrated that electromyogram signals can be monitored by our self-healable interconnects. Such information was transmitted to a prosthetic robot to control various hand motions for robust interactive human-robot interfaces.

8.
Can J Vet Res ; 83(2): 110-121, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31097873

RESUMO

The efficacy of a porcine reproductive and respiratory syndrome (PRRS) subunit vaccine was evaluated and compared with a modified-live virus (MLV) vaccine under field conditions. Three farms were selected based on their history of respiratory diseases caused by co-infection with both PRRSV-1 and PRRSV-2. In each farm, 60 pigs were randomly allocated to 2 vaccinated and 1 unvaccinated groups (20 pigs per group). One group of pigs were administered the PRRS subunit vaccine at 21 and 42 days of age and another group administered the PRRS MLV vaccine at 21 days of age. The subunit vaccine had similar efficacy and, in some instances, performed even better than the MLV vaccine. Vaccination of pigs with either of the PRRS vaccines resulted in significantly improved growth performance in Farm B but not in Farm C. In Farm A, pigs vaccinated with the PRRS subunit vaccine had a better growth performance statistically compared to those vaccinated with the PRRS MLV vaccine. At the peak of PRRSV-1 and PRRSV-2 viremia, neutralizing antibodies and T-cell responses against PRRSV-1 and PRRSV-2 were at low levels suggesting that either vaccine is only able to provide a partial protection against co-circulating PRRSV-1 and PRRSV-2.


L'efficacité d'un vaccin sous-unitaire contre le syndrome reproducteur et respiratoire porcin (SRRP) a été évaluée et comparée à un vaccin vivant modifié (VVM) dans des conditions de terrain. Trois fermes furent sélectionnées sur la base de leur historique de maladies respiratoires causées par co-infection par VSSRP-1 et VSRRP-2. Sur chaque ferme, 60 porcs furent répartis de manière aléatoire à deux groupes vaccinés et un groupe non-vacciné (20 porcs par groupe). Un groupe de porcs a reçu le vaccin SRRP sous-unitaire à 21 et 42 j d'âge et un autre groupe a reçu le VVM SRRP à 21 j d'âge. Le vaccin sous-unitaire avait une efficacité similaire, et en certaines occasions, performait mieux que le VVM. La vaccination des porcs avec un ou l'autre des vaccins SRRP, a résulté en une amélioration significative des performances de croissance pour la Ferme B mais pas pour la Ferme C. Sur la Ferme A, les porcs vaccinés avec le vaccin sous-unitaire SRRP présentaient de meilleures performances de croissance comparativement à ceux vaccinés avec le VVM du SRRP. Au pic de la virémie de VSRRP-1 et VSRRP-2, les réponses en anticorps neutralisants et en cellules T contre VSRRP-1 et VSRRP-2 étaient faibles ce qui suggère que les deux vaccins ne sont en mesure que de fournir une protection partielle contre une co-infection par VSRRP-1 et VSRRP-2.(Traduit par Docteur Serge Messier).


Assuntos
Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Interferon gama , Filogenia , Vírus da Síndrome Respiratória e Reprodutiva Suína , RNA Viral/sangue , RNA Viral/genética , Distribuição Aleatória , Suínos
9.
Artigo em Inglês | MEDLINE | ID: mdl-30961820

RESUMO

The efficacy of four commercial porcine reproductive and respiratory syndrome virus (PRRSV) modified-live virus (MLV) vaccines against respiratory disease was evaluated and compared in pig farms suffering from co-infection with PRRSV-1 and PRRSV-2. All vaccinated groups on average exhibited improved growth rate compared to the unvaccinated pigs. Interestingly, the two groups vaccinated with either of the PRRSV-2 MLV vaccines had a better overall growth rate compared to the pigs vaccinated with either of the PRRSV-1 MLV vaccines. Vaccination of pigs with either of the PRRSV-1 MLV vaccines did not result in reduction of PRRSV-1 or PRRSV-2 viremia whereas vaccination of pigs with either of the PRRSV-2 MLV vaccines resulted in the reduction of PRRSV-2 viremia only. Taken together, the results of this field study demonstrate that a PRRSV-2 MLV vaccine can be efficacious against respiratory disease caused by co-infection with PRRSV-1 and PRRSV-2.


Assuntos
Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Vacinação/veterinária , Vacinas Atenuadas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Coinfecção/virologia , Fazendas , Tipagem Molecular , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Suínos
10.
Can J Vet Res ; 83(1): 57-67, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30670903

RESUMO

The efficacy of 4 commercial porcine reproductive and respiratory syndrome virus (PRRSV) modified-live vaccines (MLV), against PRRSV-1 and PRRSV-2 was evaluated and compared in growing pigs. Two of the vaccines were based on PRRSV-1 and two on PRRSV-2. There were no significant differences between each of the two PRRSV-1 MLV vaccines and the two PRRSV-2 MLV vaccines respectively based on virology, immunological, and pathological evaluations. Vaccination with either of the PRRSV-1 MLV vaccines resulted in reduced PRRSV-1 but not PRRSV-2 viremia. Additionally, vaccination with either of the PRRSV-1 MLV vaccines resulted in reduction of lung lesions and PRRSV-1 positive cells in PRRSV-1 challenged pigs but had no significant effect in PRRSV-2 challenged pigs. In contrast, vaccination with either of the two PRRSV-2 MLV vaccines resulted in the reduction of both PRRSV-1 and PRRSV-2 viremia. The PRRSV-2 MLV vaccines were also able to effectively reduce lung lesions and PRRSV positive cells after challenge with either PRRSV-1 or PRRSV-2. Our data suggest that while vaccination with PRRSV-1 MLV vaccines can be effective against PRRSV-1, only PRRSV-2 MLV vaccines can protect against both Korean PRRSV-1 and PRRSV-2 challenges in this study.


L'efficacité de quatre vaccins vivants modifiés (VVM) commerciaux contre le virus du syndrome reproducteur et respiratoire porcin (VSRRP), a été évaluée et comparée chez des porcs en croissance infectés expérimentalement avec VSRRP-1 et VSRRP-2. Deux des vaccins étaient à base de VSRRP-1 et deux à base de VSRRP-2. Il n'y avait pas de différence significative entre chacun des deux VVM VSRRP-1 et les deux VVM VSRRP-2 respectivement sur la base des évaluations virologiques, immunologiques et pathologiques. La vaccination avec l'un ou l'autre des VVM VSRRP-1 a entrainé une réduction de la virémie causée par VSRRP-1 mais pas par VSRRP-2. De plus, la vaccination avec l'un ou l'autre des VVM VSRRP-1 a permis une réduction des lésions pulmonaires et des cellules positives pour VSRRP-1 chez les porcs infectés avec VSRRP-1 mais n'a pas eu d'effet significatif chez les porcs infectés avec VSRRP-2. La vaccination avec l'un ou l'autre des VVM SRRP-2 a résulté en une réduction de la virémie autant pour VSRRP-1 que VSRRP-2. Les VVM VSRRP-2 étaient également en mesure de réduire efficacement les lésions pulmonaires et les cellules positives pour VSRRP après l'infection soit par le VSRRP-1 ou VSRRP-2. Nos résultats suggèrent que bien que la vaccination avec les VVM VSRRP-1 peuvent être efficaces envers VSRRP-1, seulement les VVM VSRRP-2 peuvent protéger contre les infections par les VSRRP-1 et VSRRP-2 coréens utilisés dans la présente étude.(Traduit par Docteur Serge Messier).


Assuntos
Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Vacinas Virais/imunologia , Animais , Interferon gama , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , RNA Viral/sangue , Distribuição Aleatória , República da Coreia/epidemiologia , Suínos , Viremia
11.
J Vet Med Sci ; 80(9): 1463-1467, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30022776

RESUMO

The objective of this study was to compare the efficacy of a commercial porcine reproductive and respiratory syndrome (PRRS) subunit vaccine and a prototype PRRS II subunit vaccine against a highly pathogenic PRRS virus (HP-PRRSV) in pigs. Both vaccines were administered intramuscularly in 2 doses at 21 and 42 days of age, and the pigs were challenged intranasally with HP-PRRSV at 63 days of age. Pigs vaccinated with the prototype PRRS II subunit vaccine had significantly higher anti-PRRSV antibody titers, a greater number of interferon-γ-secreting cells, and a greater reduction in lung lesion scores compared to pigs vaccinated with the commercial PRRS subunit vaccine. Therefore, the commercial PRRS subunit and prototype PRRS II subunit vaccines are efficacious against HP-PRRSV.


Assuntos
Anticorpos Antivirais/sangue , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Suínos , Vacinas Virais/imunologia , Animais , Vacinas Atenuadas , Vacinas de Subunidades Antigênicas , Vacinas Virais/administração & dosagem
12.
Vet Radiol Ultrasound ; 58(3): E22-E25, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27378576

RESUMO

A 5-year-old dog presented with pollakiuria and urinary incontinence. Abdominal radiographs revealed an oval, multilayered structure with soft tissue opacity and gas lucency in the urinary bladder. Ultrasonography showed an oval luminal structure with hyper- and hypoechoic layers and internal reverberation artifacts. Following cystotomy, the hemisected plane showed a layered, pale whitish matrix with a gas layer around the core. Histopathological examination showed no evidence of cells, bacteria, or fungi. The core and laminae comprised fibrinous and mineral debris. A final diagnosis of a freely floating, gas-filled laminated debris ball was made.


Assuntos
Doenças do Cão/diagnóstico por imagem , Radiografia Abdominal/veterinária , Doenças da Bexiga Urinária/veterinária , Bexiga Urinária/patologia , Animais , Cistotomia/veterinária , Diagnóstico Diferencial , Cães , Feminino , Bexiga Urinária/diagnóstico por imagem , Doenças da Bexiga Urinária/diagnóstico por imagem , Doenças da Bexiga Urinária/etiologia , Incontinência Urinária/diagnóstico por imagem , Incontinência Urinária/etiologia , Incontinência Urinária/veterinária
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