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1.
Sensors (Basel) ; 23(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37631659

RESUMO

In this study, the problems encountered in radar cross-section (RCS) measurement experiments utilizing a dielectric barrier discharge (DBD) plasma system are examined and an effective solution is proposed. A DBD plasma system generates heat due to the high bias voltage required for plasma generation. The thermal-induced structural deformation of the DBD structure caused by this high voltage and its impact on RCS measurements are analyzed. In addition, techniques for minimizing the thermal-induced deformation and compensation methods for addressing the minimized deformation are proposed. Furthermore, RCS measurements are conducted on two kinds of DBD structures using the proposed method to experimentally demonstrate the improved agreement between the simulation and measurement results. For both structures, the RCS experimental results are in very good agreement with the simulation results, which enables accurate plasma characterization. In conclusion, it can be expected that the proposed method can be used to provide more accurate RCS measurements on various DBD structures that generate high heat.

2.
Sensors (Basel) ; 23(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38005554

RESUMO

This paper deals with the practical application of Radar Cross Section (RCS) reduction technology using plasma. Although various plasma application technologies for RCS reduction have been studied, there are still many issues to be addressed for practical implementation. In order to achieve actual application, the discharge should be sustained regardless of the external environment of the aircraft. It is also important to investigate the actual plasma parameters to determine the expected RCS reduction effect. Building upon previous studies that optimized the electrodes for RCS reduction, this study fabricates a Dielectric Barrier Discharge (DBD) source suitable for dynamic environments and verifies the power consumption during one cycle of plasma generation. The obtained results are expected to contribute to the optimization of DBD electrodes for plasma RCS reduction.

3.
BMC Nephrol ; 23(1): 291, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999520

RESUMO

BACKGROUND: Hyperphosphatemia occurs frequently in end-stage renal disease patients on hemodialysis and is associated with increased mortality. Hyperphosphatemia contributes to vascular calcification in these patients, but there is emerging evidence that it is also associated with endothelial cell dysfunction. METHODS: We conducted a cross-sectional study in hypertensive hemodialysis patients. We obtained pre-hemodialysis measurements of total peripheral resistance index (TPRI, non-invasive cardiac output monitor) and plasma levels of endothelin-1 (ET-1) and asymmetric dimethylarginine (ADMA). We ascertained the routine peridialytic blood pressure (BP) measurements from that treatment and the most recent pre-hemodialysis serum phosphate levels. We used generalized linear regression analyses to determine independent associations between serum phosphate with BP, TPRI, ET-1, and ADMA while controlling for demographic variables, parathyroid hormone (PTH), and interdialytic weight gain. RESULTS: There were 54 patients analyzed. Mean pre-HD supine and seated systolic and diastolic BP were 164 (27), 158 (21), 91.5 (17), and 86.1 (16) mmHg. Mean serum phosphate was 5.89 (1.8) mg/dL. There were significant correlations between phosphate with all pre-hemodialysis BP measurements (r = 0.3, p = .04; r = 0.4, p = .002; r = 0.5, p < .0001; and r = 0.5, p = .0003.) The correlations with phosphate and TPRI, ET-1, and ADMA were 0.3 (p = .01), 0.4 (p = .007), and 0.3 (p = .04). In our final linear regression analyses controlling for baseline characteristics, PTH, and interdialytic weight gain, independent associations between phosphate with pre-hemodialysis diastolic BP, TPRI, and ET-1 were retained (ß = 4.33, p = .0002; log transformed ß = 0.05, p = .005; reciprocal transformed ß = -0.03, p = .047). CONCLUSIONS: Serum phosphate concentration is independently associated with higher pre-HD BP, vasoconstriction, and markers of endothelial cell dysfunction. These findings demonstrate an additional negative impact of hyperphosphatemia on cardiovascular health beyond vascular calcification. TRIAL REGISTRATION: The study was part of a registered clinical trial, NCT01862497 (May 24, 2013).


Assuntos
Hiperfosfatemia , Hipertensão , Falência Renal Crônica , Calcificação Vascular , Pressão Sanguínea/fisiologia , Estudos Transversais , Células Endoteliais , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Falência Renal Crônica/complicações , Hormônio Paratireóideo , Fosfatos , Diálise Renal/efeitos adversos , Calcificação Vascular/complicações , Vasoconstrição , Aumento de Peso
4.
Sensors (Basel) ; 21(21)2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34770732

RESUMO

This paper proposes a post-processing method called bidirectional interpolation method for sampling-based path planning algorithms, such as rapidly-exploring random tree (RRT). The proposed algorithm applies interpolation to the path generated by the sampling-based path planning algorithm. In this study, the proposed algorithm is applied to the path created by RRT-connect and six environmental maps were used for the verification. It was visually and quantitatively confirmed that, in all maps, not only path lengths but also the piecewise linear shape were decreased compared to the path generated by RRT-connect. To check the proposed algorithm's performance, visibility graph, RRT-connect algorithm, Triangular-RRT-connect algorithm and post triangular processing of midpoint interpolation (PTPMI) were compared in various environmental maps through simulation. Based on these experimental results, the proposed algorithm shows similar planning time but shorter path length than previous RRT-like algorithms as well as RRT-like algorithms with PTPMI having a similar number of samples.


Assuntos
Robótica , Algoritmos , Simulação por Computador , Tempo
5.
Sensors (Basel) ; 21(2)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33419005

RESUMO

This paper proposed a triangular inequality-based rewiring method for the rapidly exploring random tree (RRT)-Connect robot path-planning algorithm that guarantees the planning time compared to the RRT algorithm, to bring it closer to the optimum. To check the proposed algorithm's performance, this paper compared the RRT and RRT-Connect algorithms in various environments through simulation. From these experimental results, the proposed algorithm shows both quicker planning time and shorter path length than the RRT algorithm and shorter path length than the RRT-Connect algorithm with a similar number of samples and planning time.

6.
Vet Radiol Ultrasound ; 61(3): 291-301, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32173960

RESUMO

Radiography is a standard diagnostic test for characterizing left heart enlargement in dogs however limited information is available on the effects of respiratory phases. This prospective and retrospective method comparison study investigated the respiratory effect on the size and shape of the left heart in dogs to determine the usefulness of expiratory radiographs to detect enlargements in the left atrium (LA) and left ventricle (LV). Thoracic radiographs taken at full inspiration and expiration were evaluated in 20 normal beagles and 100 dogs diagnosed with mitral regurgitation (MR). Vertebral heart score (VHS), vertebral left atrial size, elevation of the carina, and dorsal bulging of LA on lateral view and lateral bulging of the left auricular appendage and LV on ventrodorsal view were assessed. In normal dogs, there were no significant differences in the evaluative factors between inspiration and expiration. In dogs with MR, VHS did not change according to respiration. However, bulging of the LA, left auricular appendage, and LV had sharp margin during expiration compared with inspiration. The expiratory radiographic finding of LA bulging had a higher correlation with the LA to aorta ratio compared with LA bulging in the inspiratory radiography. Using a LA to aorta echocardiographic ratio greater than 1.5 as the gold standard, the radiographic sensitivity for LA enlargement was higher during expiration than inspiration. These findings of our study indicated that expiratory radiography can be helpful to support the detection of left heart enlargement, although it can overestimate LA enlargement in dogs with MR.


Assuntos
Cardiomegalia/veterinária , Doenças do Cão/diagnóstico por imagem , Átrios do Coração/diagnóstico por imagem , Insuficiência da Valva Mitral/veterinária , Radiografia/veterinária , Animais , Aorta/diagnóstico por imagem , Cardiomegalia/diagnóstico por imagem , Cardiomegalia/patologia , Doenças do Cão/patologia , Cães , Ecocardiografia/veterinária , Feminino , Átrios do Coração/patologia , Masculino , Insuficiência da Valva Mitral/diagnóstico por imagem , Estudos Prospectivos , Radiografia/métodos , Estudos Retrospectivos
7.
Sensors (Basel) ; 19(6)2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871188

RESUMO

There are various motion planning techniques for robots or agents, such as bug algorithm, visibility graph, Voronoi diagram, cell decomposition, potential field, and other probabilistic algorithms. Each technique has its own advantages and drawbacks, depending on the number and shape of obstacles and performance criteria. Especially, a potential field has vector values for movement guidance to the goal, and the method can be used to make an instantaneous and smooth robot movement path without an additional controller. However, there may be some positions with zero force value, called local minima, where the robot or agent stops and cannot move any further. There are some solutions for local minima, such as random walk or backtracking, but these are not yet good enough to solve the local minima problem. In this paper, we propose a novel movement guidance method that is based on the water sink model to overcome the previous local minima problem of potential field methods. The concept of the water sink model is to mimic the water flow, where there is a sink or bathtub with a plughole and floating piece on the water. The plughole represents the goal position and the floating piece represents robot. In this model, when the plug is removed, water starts to drain out via the plughole and the robot can always reach the goal by the water flow. The water sink model simulator is implemented and a comparison of experimental results is done between the water sink model and potential field.

8.
Sensors (Basel) ; 18(9)2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-30189668

RESUMO

This paper proposes an adaptive duty-cycled hybrid X-MAC (ADX-MAC) protocol for energy-efficient forest fire prediction. The Asynchronous sensor network protocol, X-MAC protocol, acquires additional environmental status details from each forest fire monitoring sensor for a given period, and then changes the duty-cycle sleep interval to efficiently calculate forest fire occurrence risk according to the environment. Performance was verified experimentally, and the proposed ADX-MAC protocol improved throughput by 19% and was 24% more energy efficient compared to the X-MAC protocol. The duty-cycle was shortened as forest fire probability increased, ensuring forest fires were detected at faster cycle rate.

9.
Sensors (Basel) ; 18(8)2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-30046016

RESUMO

A dual-band circularly polarized (CP) dielectric resonator antenna (DRA) designed on multi-layer substrates is proposed. An asymmetric C-shaped metallic strip is also incorporated into the upper side of the top substrate in the proposed design. The hexagonal dielectric resonator (DR) is excited by the proposed 3-D meandered probe, which generates multiple orthogonal TE-modes. It is found that the lower CP band arises due to the pair of fundamental modes of the hexagonal DR. In the upper CP band, pairs of higher broadside and even modes of the hexagonal DR are combined with a CP band that is induced by the asymmetric C-shaped metallic strip to yield a wide 3 dB axial ratio bandwidth (ARBW). A prototype of the proposed DRA is fabricated for experimental verification. The antenna exhibits a measured -10 dB reflection bandwidth of 56.43% (2.15⁻3.84 GHz). The far-field measurement shows measured 3 dB ARBWs of 7.56% (2.29⁻2.47 GHz) with a peak gain of 5.6 dBic and 16.47% (3.12⁻3.68 GHz) with a peak gain of 7.84 dBic in the lower and upper bands, respectively.

10.
Sensors (Basel) ; 18(7)2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30041466

RESUMO

A cable-driven parallel robot has benefits of wide workspace, high payload, and high dynamic response owing to its light cable actuator utilization. For wide workspace applications, in particular, the body frame becomes large to cover the wide workspace that causes robot kinematic errors resulting from geometric uncertainty. However, appropriate sensors as well as inexpensive and easy calibration methods to measure the actual robot kinematic parameters are not currently available. Hence, we present a calibration sensor device and an auto-calibration methodology for the over-constrained cable-driven parallel robots using one-dimension laser distance sensors attached to the robot end-effector, to overcome the robot geometric uncertainty and to implement precise robot control. A novel calibration workflow with five phases-preparation, modeling, measuring, identification, and adjustment-is proposed. The proposed calibration algorithms cover the cable-driven parallel robot kinematics, as well as uncertainty modeling such as cable elongation and pulley kinematics. We performed extensive simulations and experiments to verify the performance of the suggested method using the MINI cable robot. The experimental results show that the kinematic parameters can be identified correctly with 0.92 mm accuracy, and the robot position control accuracy is increased by 58%. Finally, we verified that the developed calibration sensor devices and the calibration methodology are applicable to the massive-size cable-driven parallel robot system.

11.
Sensors (Basel) ; 17(8)2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28820465

RESUMO

A vertical-strip-fed dielectric resonator antenna exhibiting broadband circular polarization characteristics is presented. A broad 3 dB axial ratio bandwidth (ARBW) is achieved by combining multiple orthogonal modes due to the use of a special-shaped dielectric resonator. The proposed antenna is fabricated to evaluate its actual performance capabilities. The antenna exhibits a measured 3 dB ARBW of 44.2% (3.35-5.25 GHz), lying within a -10 dB reflection bandwidth of 82.7% (2.44-5.88 GHz). The measured peak gain within 3 dB ARBW is found to be 5.66 dBic at 4.8 GHz. The measured results are in good agreement with the simulated results.

12.
Anim Cogn ; 19(4): 861-5, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26939544

RESUMO

Recent findings report that wild animals can recognize individual humans. To explain how the animals distinguish humans, two hypotheses are proposed. The high cognitive abilities hypothesis implies that pre-existing high intelligence enabled animals to acquire such abilities. The pre-exposure to stimuli hypothesis suggests that frequent encounters with humans promote the acquisition of discriminatory abilities in these species. Here, we examine individual human recognition abilities in a wild Antarctic species, the brown skua (Stercorarius antarcticus), which lives away from typical human settlements and was only recently exposed to humans due to activities at Antarctic stations. We found that, as nest visits were repeated, the skua parents responded at further distances and were more likely to attack the nest intruder. Also, we demonstrated that seven out of seven breeding pairs of skuas selectively responded to a human nest intruder with aggression and ignored a neutral human who had not previously approached the nest. The results indicate that Antarctic skuas, a species that typically inhabited in human-free areas, are able to recognize individual humans who disturbed their nests. Our findings generally support the high cognitive abilities hypothesis, but this ability can be acquired during a relatively short period in the life of an individual as a result of interactions between individual birds and humans.


Assuntos
Charadriiformes , Comportamento de Nidação , Reconhecimento Psicológico , Percepção Visual , Agressão , Animais , Animais Selvagens , Regiões Antárticas , Aves , Feminino , Humanos , Masculino
13.
BJU Int ; 115(6): 907-12, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24612460

RESUMO

OBJECTIVE: To identify an appropriate risk stratification system for intermediate-risk prostate cancer (PCa). PATIENTS AND METHODS: We reviewed the data on 1559 patients who were treated with radical prostatectomy (RP) at our institution between 2005 and 2013 and classified them according to National Comprehensive Cancer Network (NCCN) risk groups. For our analyses, intermediate-risk PCa was designated as unfavourable intermediate-risk PCa if it met at least one of the following two criteria: biopsy Gleason score 4 + 3 and/or presence of ≥ 2 intermediate-risk criteria. All other men with intermediate-risk PCa were designated as having favourable intermediate-risk disease. Postoperative outcomes, including biochemical recurrence (BCR)-free survival, were calculated and compared using the log-rank test and Cox proportional hazards model. RESULTS: In multivariable analysis, biopsy Gleason score 4 + 3 and multiple (≥ 2) intermediate-risk criteria were observed to be independent predictors of BCR risk among men in the intermediate-risk group undergoing RP. The favourable intermediate-risk group had a significantly higher 5-year BCR-free survival compared with the unfavourable intermediate-risk group (87.5 vs 66.5%; P < 0.001). The unfavourable intermediate-risk group had significantly higher 5-year BCR-free survival than the high-risk group (66.5 vs 47.9%; P < 0.001) while the favourable intermediate-risk group had significantly lower 5-year BCR-free survival than the low-risk group (87.5 vs 93.5%; P = 0.002). CONCLUSIONS: A marked heterogeneity exists in the biochemical outcomes of contemporary patients with intermediate-risk PCa who undergo definitive RP. According to biopsy Gleason score and number of intermediate-risk criteria present, the intermediate-risk group should be sub-divided into those with favourable and unfavourable intermediate-risk disease.


Assuntos
Neoplasias da Próstata/classificação , Neoplasias da Próstata/diagnóstico , Idoso , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos , Risco
14.
Environ Sci Technol ; 49(22): 13628-38, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26502059

RESUMO

Legacy and new persistent organic pollutants (POPs), including polychlorinated naphthalenes (PCNs), Dechlorane Plus (DPs) and related compounds (Dechloranes), hexabromocyclododecanes (HBCDs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs), were analyzed in avian tissue samples from King George Island, Antarctica. The avian species consisted of the Gentoo penguin (Pygoscelis papua), the Adelie penguin (Pygoscelis adeliae), the South polar skua (Stercorarius maccormicki), and the Brown skua (Stercorarius antarcticus). HBCDs were detected in all samples and ranged from 1.67-713 pg/g-lipid. In the penguin samples, the concentrations of PCNs ranged from 0.69-2.07 ng/g-lipid, whereas those in the skua samples ranged from 7.41-175 ng/g-lipid. The levels of Dechloranes ranged from 0.60-1.30 ng/g-lipid in the penguin samples and from 6.57-47.4 ng/g-lipid in the skua samples. The concentrations and congener distributions of OCPs and PCBs were similar to the results of previous reports. The three new POPs were detected in all samples, and this study was one of the first reports on the occurrence of these pollutants in the Antarctic biota. Because Antarctica is one of the most pristine places on Earth, the detection of new POPs in the Antarctic birds, especially penguins, is direct evidence of the long-range transport of pollutants. Furthermore, the concentration ratios of the penguin to the skua samples (BMFs-p) were greater than 1 in most legacy and new POPs, and the BMFs-p values of the new POPs were comparable to those of some OCPs, suggesting a possibility of biomagnification. Despite the small sample size, the results of this study identified POP contamination of the Antarctic avian species and long-range transport and biomagnification of HBCDs, Dechloranes, and PCNs.


Assuntos
Charadriiformes , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Spheniscidae , Animais , Regiões Antárticas , Hidrocarbonetos Clorados/análise , Ilhas , Compostos Orgânicos/análise , Praguicidas/análise , Bifenilos Policlorados/análise
15.
Int J Urol ; 22(2): 153-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25421791

RESUMO

OBJECTIVES: To evaluate the efficacy of targeted therapy after complete resection of metastatic lesions in patients with metastatic renal cell carcinoma. METHODS: We retrospectively reviewed the medical records of 53 patients with metastatic renal cell carcinoma who underwent complete surgical resection of metastatic lesions between January 2006 and December 2012. Immediate postoperative targeted therapy was given to a subgroup of patients. Progression-free survival and cancer-specific survival were assessed. RESULTS: All patients underwent curative surgery for a primary tumor. A total of 13 patients (24.5%) had metastatic disease at initial diagnosis, and 49 (92.5%) had single-organ involvement at the time of first metastasis. None of the patients met the poor-risk criteria. Of the 19 patients who received immediate postoperative targeted therapy, five (26.3%) experienced relapse. Of the 34 patients who did not receive immediate postoperative targeted therapy, 27 (79.4%) experienced disease recurrence. Targeted therapy was restarted in 30 patients (93.8%) after relapse with excellent disease control rates (complete response: 3.3%, partial response: 36.7%, stable disease: 46.7%). Immediate postoperative targeted therapy was associated with better median progression-free survival (not reached vs 20.0 months; P = 0.017), but not better cancer-specific survival. CONCLUSIONS: Postoperative targeted therapy after complete metastasectomy seems to be associated with better progression-free survival in patients with metastatic renal cell carcinoma, but not with cancer-specific survival.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Renais/terapia , Neoplasias Renais/terapia , Nefrectomia , Cuidados Pós-Operatórios/métodos , Idoso , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/secundário , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , República da Coreia/epidemiologia , Estudos Retrospectivos , Taxa de Sobrevida/tendências
16.
Proc Natl Acad Sci U S A ; 108(41): 17004-9, 2011 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-21953697

RESUMO

α-Synuclein is an abundant brain protein that binds to lipid membranes and is involved in the recycling of presynaptic vesicles. In Parkinson disease, α-synuclein accumulates in intraneuronal inclusions often containing ubiquitin chains. Here we show that the ubiquitin ligase Nedd4, which functions in the endosomal-lysosomal pathway, robustly ubiquitinates α-synuclein, unlike ligases previously implicated in its degradation. Purified Nedd4 recognizes the carboxyl terminus of α-synuclein (residues 120-133) and attaches K63-linked ubiquitin chains. In human cells, Nedd4 overexpression enhances α-synuclein ubiquitination and clearance by a lysosomal process requiring components of the endosomal-sorting complex required for transport. Conversely, Nedd4 down-regulation increases α-synuclein content. In yeast, disruption of the Nedd4 ortholog Rsp5p decreases α-synuclein degradation and enhances inclusion formation and α-synuclein toxicity. In human brains, Nedd4 is present in pigmented neurons and is expressed especially strongly in neurons containing Lewy bodies. Thus, ubiquitination by Nedd4 targets α-synuclein to the endosomal-lysosomal pathway and, by reducing α-synuclein content, may help protect against the pathogenesis of Parkinson disease and other α-synucleinopathies.


Assuntos
Encéfalo/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , alfa-Sinucleína/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Linhagem Celular , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Endossomos/metabolismo , Células HEK293 , Humanos , Técnicas In Vitro , Corpos de Lewy/metabolismo , Locus Cerúleo/metabolismo , Lisina/química , Lisossomos/metabolismo , Camundongos , Dados de Sequência Molecular , Ubiquitina-Proteína Ligases Nedd4 , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , Ratos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Substância Negra/metabolismo , Especificidade por Substrato , Complexos Ubiquitina-Proteína Ligase/genética , Complexos Ubiquitina-Proteína Ligase/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , alfa-Sinucleína/química , alfa-Sinucleína/genética
17.
Ann Work Expo Health ; 68(2): 217-221, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38156670

RESUMO

Sulfuric acid, a constituent of lead-acid batteries, is an extremely hazardous substance, necessitating utmost caution. Unfortunately, many workers that utilize battery-operated equipment remain unaware of the potential exposure. This study aims to evaluate the potential exposure to sulfuric acid among workers employed by small companies associated with the operation of floor cleaning equipment powered by lead-acid batteries. Only cleaning equipment (hand-push and ride-on types) that required supplementation of lead-acid batteries with distilled water were targeted. Exposure measurement and analysis were performed according to the guidelines of NIOSH and including personal sampling and stationary sampling on the equipment. Exposure measurements indicated that workers were exposed to sulfuric acid. Additionally, the concentration level was slightly elevated in the stationary samples compared to personal samples. This study affirms that workers can experience exposure to sulfuric acid, even in the absence of direct handling of the substance. Consequently, there is a need to recognize and mitigate the potential risks.


Assuntos
Exposição Ocupacional , Humanos , Substâncias Perigosas , Ácidos Sulfúricos/análise
18.
Adv Sci (Weinh) ; 11(22): e2310197, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38493313

RESUMO

Hexagonal boron nitride (h-BN) is a key ingredient for various 2D van der Waals heterostructure devices, but the exact role of h-BN encapsulation in relation to the internal defects of 2D semiconductors remains unclear. Here, it is reported that h-BN encapsulation greatly removes the defect-related gap states by stabilizing the chemisorbed oxygen molecules onto the defects of monolayer WS2 crystals. Electron energy loss spectroscopy (EELS) combined with theoretical analysis clearly confirms that the oxygen molecules are chemisorbed onto the defects of WS2 crystals and are fixated by h-BN encapsulation, with excluding a possibility of oxygen molecules trapped in bubbles or wrinkles formed at the interface between WS2 and h-BN. Optical spectroscopic studies show that h-BN encapsulation prevents the desorption of oxygen molecules over various excitation and ambient conditions, resulting in a greatly lowered and stabilized free electron density in monolayer WS2 crystals. This suppresses the exciton annihilation processes by two orders of magnitude compared to that of bare WS2. Furthermore, the valley polarization becomes robust against the various excitation and ambient conditions in the h-BN encapsulated WS2 crystals.

19.
J Cosmet Dermatol ; 22(10): 2780-2784, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37060183

RESUMO

BACKGROUND: Thread lifting is a common procedure in minimally invasive esthetic techniques and can also be used to raise the drooping soft tissue of the forehead by vertically inserting threads into the forehead. AIMS: This study aimed to examine the effect of forehead thread lifting on enhancing upper eyelid opening. METHODS: Fifteen patients were included in this study, all of whom underwent eyebrow thread lifting with MINT LIFT® UP. Photographs of the patients were taken before, immediately after, and 1 and 12 weeks after surgery. Changes in the position of the eyebrows and eyelids were measured. The paired t-test was used to determine the statistical significance of differences. RESULTS: At 1 week after surgery, the eyebrows were at a lower level compared with before surgery, and no significant changes in eye-opening were observed. However, at 12 weeks after surgery, the eyebrows and upper eyelids were both significantly elevated when compared to the preoperative state. CONCLUSIONS: Eyebrow lifting can be performed using multidirectional thread lifting.


Assuntos
Sobrancelhas , Ritidoplastia , Humanos , Ritidoplastia/métodos , Testa/cirurgia , Pálpebras/cirurgia
20.
Animals (Basel) ; 13(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38067079

RESUMO

Over the last decade, highly pathogenic avian influenza (HPAI) has severely affected poultry production systems across the globe. In particular, massive pre-emptive depopulation of all poultry within a certain distance has raised concerns regarding animal welfare and food security. Thus, alternative approaches to reducing unnecessary depopulation, such as risk-based depopulation, are highly demanded. This paper proposes a data-driven method to generate a rule table and risk score for each farm to identify preventive measures against HPAI. To evaluate the proposed method, 105 cases of HPAI occurring in a total of 381 farms in Jeollanam-do from 2014 to 2023 were evaluated. The accuracy of preventive measure identification was assessed for each case using both the conventional culling method and the proposed data-driven method. The evaluation showed that the proposed method achieved an accuracy of 84.19%, significantly surpassing the previous 10.37%. The result was attributed to the proposed method reducing the false-positive rate by 83.61% compared with the conventional method, thereby enhancing the reliability of identification. The proposed method is expected to be utilized in selecting farms for monitoring and management of HPAI.

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