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1.
Sensors (Basel) ; 24(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38894130

RESUMO

Accurate three-dimensional (3D) localization within indoor environments is crucial for enhancing item-based application services, yet current systems often struggle with localization accuracy and height estimation. This study introduces an advanced 3D localization system that integrates updated ultra-wideband (UWB) sensors and dual barometric pressure (BMP) sensors. Utilizing three fixed UWB anchors, the system employs geometric modeling and Kalman filtering for precise tag 3D spatial localization. Building on our previous research on indoor height measurement with dual BMP sensors, the proposed system demonstrates significant improvements in data processing speed and stability. Our enhancements include a new geometric localization model and an optimized Kalman filtering algorithm, which are validated by a high-precision motion capture system. The results show that the localization error is significantly reduced, with height accuracy of approximately ±0.05 m, and the Root Mean Square Error (RMSE) of the 3D localization system reaches 0.0740 m. The system offers expanded locatable space and faster data output rates, delivering reliable performance that supports advanced applications requiring detailed 3D indoor localization.

2.
Anticancer Res ; 44(7): 2847-2859, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38925815

RESUMO

BACKGROUND/AIM: Human melanoma-associated antigen A2 (hMAGEA2) family members play several roles in many types of cancer and have been explored as potential prognostic markers. In this study, we investigated the molecular mechanism underlying hMAGEA2-mediated tumorigenesis of prostate cancer. MATERIALS AND METHODS: Immunohistochemistry and western blot were used to assess protein expression whereas microarray and quantitative reverse transcription-PCR determined mRNA expression. CCK-8 assay was used to determine cell proliferation. Colony formation assay was used to examine tumorigenesis. Migration and invasion were examined using a transwell assay. Propidium iodide (PI)/Annexin V double staining was performed to measure apoptosis. Transcriptional activity was measured using Dual-luciferase reporter assay. RESULTS: hMAGEA2 was highly over-expressed in human prostate cancer tissues compared to benign prostatic hyperplasia tissues. To elucidate its biological function in prostate cancer, we established two stable hMAGEA2-knockdown prostate cancer cell lines, PC3M and 22RV1, and found that they presented significantly decreased proliferation, anchorage-independent colony formation, migration, and invasion. As hMAGEA2 knockdown suppressed prostate cancer cell growth, we examined its potential influence on tumor apoptosis. hMAGEA2-knockdown cell lines displayed early apoptosis. Moreover, knockdown of hMAGEA2 resulted in the down-regulation of EFNA3 expression. Luciferase assay showed that hMAGEA2 bound to the EFNA promoter region and regulated its transcription. Down-regulation of EFNA3 expression led to decreased Ras/Braf/MEK/Erk1/2 phosphorylation and, consequently, inhibited prostate cancer progression. CONCLUSION: hMAGEA2 promotes prostate cancer growth, metastasis, and tumorigenesis by regulating the EFNA3-Erk1/2 signaling pathway, indicating its potential as a therapeutic marker for prostate cancer.


Assuntos
Apoptose , Proliferação de Células , Progressão da Doença , Sistema de Sinalização das MAP Quinases , Neoplasias da Próstata , Humanos , Masculino , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Sistema de Sinalização das MAP Quinases/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Fatores de Transcrição
3.
Sci Rep ; 14(1): 3491, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347145

RESUMO

Recently, diesel engine emissions have been designated as a first-class carcinogen by the World Health Organization (WHO). As such, problems with diesel engine emissions continue to increase around the world. This study aimed to analyze the emissions (CO, NOx, PM) of agricultural tractors during farming operations in order to build a reliable national inventory of air pollutant emissions. Emission data were collected using a portable emission measurement system during actual agricultural operation. The load factor (LF) of the engine was calculated using the collected engine information, the emission factor was analyzed using the LF and the measured emission. The LF was significantly different from the current standard value of 0.48, which is used in Korea to calculate exhaust emissions. The deviation ratio of the emission factor was 0.039 ~ 56.59 compared to Tier-4 emission regulation standards. Under many conditions, the calculated emission factor was higher than the emission limit. Thus, this study provides useful information for emission inventory construction through emission calculation under actual conditions and suggests the need to realize the currently applied emission factor.

4.
Am J Emerg Med ; 78: 132-139, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38271790

RESUMO

INTRODUCTION: Considering the few studies evaluating bystander cardiopulmonary resuscitation (CPR) performance, we sought to analyze differences in bystander CPR performance with and without the use of our self-developed animated GIFs based on dispatcher-assisted CPR simulation. METHODS: A total of 80 adults who had not received CPR training over the past two years participated in the study. Among them, 40 people were classified into the auditory group (receiving CPR instructions only over the phone), and the other 40 people were classified into the audiovisual group (receiving CPR instructions over the phone after receiving images on a smartphone). All participants were asked to perform adult and infant CPR for 2 min. CPR performance was recorded using two video cameras (front and side) and analyzed by two emergency physicians, whereas CPR quality was measured using Resusci Anne & Baby QCPR Mk II (Laerdal). RESULTS: In the adult CPR study, the audiovisual group had higher performance scores for adequacy of "knee position," "hand posture," "elbow extension," and "vertical compression," as well as higher Standard Posture Completeness and Instruction Performance scores (p < 0.001). No significant difference in CPR quality was observed between the two groups. In the infant CPR study, audiovisual group had higher performance scores in adequacy of "compression site," "finger posture," and "vertical compression," as well as higher Standard Posture Completeness and Instruction Performance scores (p < 0.001). Regarding CPR quality, the audiovisual group had higher scores for "adequate compression rate ratio" (p = 0.047). CONCLUSION: Audiovisual guidance using animated GIFs more effectively improved CPR Standard Posture Completeness and Instruction Performance than did traditional auditory guidance.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca Extra-Hospitalar , Adulto , Humanos , Reanimação Cardiopulmonar/métodos , Telefone , Smartphone , Simulação por Computador , Pressão
5.
Am J Chin Med ; 51(5): 1309-1333, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37385965

RESUMO

Prostate cancer (PC) is the second leading cause of cancer-related death among men. Treatment of PC becomes difficult after progression because PC that used to be androgen-dependent becomes androgen-independent prostate cancer (AIPC). Veratramine, an alkaloid extracted from the root of the Veratrum genus, has recently been reported to have anticancer effects that work against various cancers; however, its anticancer effects and the underlying mechanism of action in PC remain unknown. We investigated the anticancer effects of veratramine on AIPC using PC3 and DU145 cell lines, as well as a xenograft mouse model. The antitumor effects of veratramine were evaluated using the CCK-8, anchorage-independent colony formation, trans-well, wound healing assays, and flow cytometry in AIPC cell lines. Microarray and proteomics analyses were performed to investigate the differentially expressed genes and proteins induced by veratramine in AIPC cells. A xenograft mouse model was used to confirm the therapeutic response and in vivo efficacy of veratramine. Veratramine dose dependently reduced the proliferation of cancer cells both in vitro and in vivo. Moreover, veratramine treatment effectively suppressed the migration and invasion of PC cells. The immunoblot analysis revealed that veratramine significantly downregulated Cdk4/6 and cyclin D1 via the ATM/ATR and Akt pathways, both of which induce a DNA damage response that eventually leads to G1 phase arrest. In this study, we discovered that veratramine exerted antitumor effects on AIPC cells. We demonstrated that veratramine significantly inhibited the proliferation of cancer cells via G0/G1 phase arrest induced by the ATM/ATR and Akt pathways. These results suggest that veratramine is a promising natural therapeutic agent for AIPC.


Assuntos
Androgênios , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Androgênios/farmacologia , Androgênios/uso terapêutico , Proliferação de Células , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Ciclo Celular , Linhagem Celular Tumoral , Apoptose , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/farmacologia
6.
Environ Res ; 233: 116411, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37354929

RESUMO

The growing use of plastic materials has resulted in a constant increase in the risk associated with microplastics (MPs). Ultra-violet (UV) light and wind break down modify MPs in the environment into smaller particles known as weathered MPs (WMPs) and these processes increase the risk of MP toxicity. The neurotoxicity of weathered polystyrene-MPs remains unclear. Therefore, it is important to understand the risks posed by WMPs. We evaluated the chemical changes of WMPs generated under laboratory-synchronized environmentally mimetic conditions and compared them with virgin MPs (VMPs). We found that WMP had a rough surface, slight yellow color, reduced molecular weight, and structural alteration compared with those of VMP. Next, 2 µg of ∼100 µm in size of WMP and VMP were orally administered once a day for one week to C57BL/6 male mice. Proteomic analysis revealed that the WMP group had significantly increased activation of immune and neurodegeneration-related pathways compared with that of the VMP group. Consistently, in in vitro experiments, the human brain-derived microglial cell line (HMC-3) also exhibited a more severe inflammatory response to WMP than to VMP. These results show that WMP is a more profound inflammatory factor than VMP. In summary, our findings demonstrate the toxicity of WMPs and provide theoretical insights into their potential risks to biological systems and even humans in the ecosystem.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Humanos , Camundongos , Masculino , Microplásticos/toxicidade , Plásticos , Poliestirenos/toxicidade , Poliestirenos/análise , Proteoma , Ecossistema , Proteômica , Camundongos Endogâmicos C57BL , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Encéfalo
7.
Biochem Biophys Res Commun ; 635: 99-107, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36265288

RESUMO

Although several studies have focused on cancer diagnosis and therapy, prostate cancer (PC) remains an intractable disease. Androgen deprivation therapy (ADT), which is used to treat early stage PC can lead to the development of castration-resistant prostate cancer (CRPC), which is highly associated with androgen receptor (AR) mutations. Nucleolar and coiled-body phosphoprotein 1 (NOLC1) is a chaperone that shuttles between the nucleus and the cytoplasm. Studies suggest that NOLC1 regulates PC progression; however, the underlying mechanisms remain unclear. Herein, we showed that NOLC1 knockdown suppresses PC cell proliferation by altering the signaling pathways and the expression of various proteins involved in DNA replication, amino acid metabolism, and RNA processing. Mechanistically, NOLC1 knockdown suppressed cell cycle progression by inhibiting AKT phosphorylation and ß-catenin accumulation. Finally, we showed that NOLC1 expression is higher in human PC than in human hyperplastic prostate tissues. Altogether, we demonstrated that NOLC1 knockdown suppresses the progression of both AR-positive and AR-negative PC cells by inducing changes in the expression of several genes leading to cell cycle arrest. Thus, NOLC1 might be a novel and promising therapeutic target for PC.


Assuntos
Neoplasias de Próstata Resistentes à Castração , beta Catenina , Masculino , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Próstata/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Fosforilação , Antagonistas de Androgênios , Linhagem Celular Tumoral , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo
8.
Sensors (Basel) ; 22(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35408083

RESUMO

In this work, we present the overground prototype gait-rehabilitation robot for using motion assistance and training for paralyzed patients. In contrast to the existing gait-rehabilitation robots, which focus on the sagittal plane motion of the hip and knee, we aim to develop a mobile-based pelvic support gait-rehabilitation system that includes a pelvic obliquity support mechanism and a lower-limb exoskeleton. To achieve this, a scissor mechanism is proposed to generate the paralyzed patient's pelvic obliquity motion and weight support. Moreover, the lower limb exoskeleton robot is integrated with the developed system to provide the patient's gait by correcting mechanical aids. We used computer-aided analysis to verify the performance of the prototype hardware itself. Through these methods, it was shown that our motor can sufficiently lift 100 kg of user weight through the scissor mechanism, and that the mobile driving wheel motor can operate at a speed of 1.6 m/s of human walking, showing that it can be used for gait rehabilitation of patients in need of a lower speed. In addition, we verified that the system drives the model by generating pelvic motion, and we verified the position controller of the integrated system, which supports the multi-degree motion by creating hip/knee/pelvic motion with a human dummy mannequin and systems. We believe that the proposed system can help address the complex rehabilitation motion assistance and training of paralyzed patients.


Assuntos
Exoesqueleto Energizado , Transtornos Neurológicos da Marcha , Robótica , Fenômenos Biomecânicos , Marcha , Hemiplegia , Humanos , Caminhada
9.
Sensors (Basel) ; 22(7)2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35408364

RESUMO

The purpose of this study was to analyze the tillage depth effect on the tractor-moldboard plow systems in various soil environments and tillage depths using a field load measurement system. A field load measurement system can measure the engine load, draft force, travel speed, wheel axle load, and tillage depth in real-time. In addition, measurement tests of soil properties in the soil layer were preceded to analyze the effect of field environments. The presented results show that moldboard plow at the same tillage depth had a wide range of influences on the tractor's working load and performance under various environments. As the draft force due to soil-tool interaction occurred in the range of 5.6-17.7 kN depending on the field environment, the overall mean engine torque and rear axle torque were up to 2.14 times and 1.67 times higher in hard and clayey soil, respectively, than in soft soil environments. In addition, the results showed tractive efficiency of 0.56-0.73 and were analyzed to have a lugging ability of 67.8% with a 44% maximum torque rise. The engine power requirement in hardpan was similar within 3.6-9.6%, but the power demand of the rear axle differed by up to 18.4%.


Assuntos
Agricultura , Solo , Agricultura/métodos
10.
Differentiation ; 125: 18-26, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35349880

RESUMO

Mouse embryonic stem cells (mESCs) are characterized by self-renewal and pluripotency and can undergo differentiation into the three germ layers (ectoderm, mesoderm, and endoderm). Melanoma-associated antigen D1 (Maged1), which is expressed in all developing and adult tissues, modulates tissue regeneration and development. In the present study, we examined the expression and function of Maged1 in mESCs. Maged1 protein and mRNA expression increased during mESC differentiation. The pluripotency of mESCs was significantly reduced through extracellular signal-regulated kinase 1/2 phosphorylation upon knockdown of Maged1, and through G1 cell cycle arrest during cell division, resulting in significantly reduced mESC proliferation. Moreover, the diameter of the embryoid bodies was significantly reduced, accompanied by increased levels of ectodermal differentiation markers and decreased levels of mesodermal and endodermal differentiation markers. Maged1-knockdown mESC lines showed significantly reduced teratoma volumes and inhibition of teratoma formation in nude mice. Additionally, we observed increased ectodermal markers but decreased mesodermal and endodermal markers in teratoma tissues. These findings show that Maged1 affects mESC pluripotency, proliferation, cell cycle, and differentiation, thereby contributing to our understanding of the basic molecular biological mechanisms and potential roles of Maged1 as a regulator of various mESC properties.


Assuntos
Células-Tronco Embrionárias Murinas , Animais , Antígenos de Diferenciação/metabolismo , Ciclo Celular/genética , Morte Celular , Diferenciação Celular/genética , Divisão Celular , Camundongos , Camundongos Nus , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Teratoma/genética , Teratoma/metabolismo , Teratoma/patologia
11.
Sensors (Basel) ; 22(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35161531

RESUMO

This study aims to design, develop, and evaluate the traction performance of an electric all-wheel-drive (AWD) tractor based on the power transmission and electric systems. The power transmission system includes the electric motor, helical gear reducer, planetary gear reducer, and tires. The electric system consists of a battery pack and charging system. An engine-generator and charger are installed to supply electric energy in emergency situations. The load measurement system consists of analog (current) and digital (battery voltage and rotational speed of the electric motor) components using a controller area network (CAN) bus. A traction test of the electric AWD tractor was performed towing a test vehicle. The output torques of the tractor motors during the traction test were calculated using the current and torque curves provided by the motor manufacturer. The agricultural work performance is verified by comparing the torque and rpm (T-N) curve of the motor with the reduction ratio applied. The traction is calculated using torque and specifications of the wheel, and traction performance is evaluated using tractive efficiency (TE) and dynamic ratio (DR). The results suggest a direction for the improvement of the electric drive system in agricultural research by comparison with the conventional tractor through the analysis of the agricultural performance and traction performance of the electric AWD tractor.


Assuntos
Agricultura , Tração , Fontes de Energia Elétrica , Eletricidade , Torque
12.
J Cell Biochem ; 123(3): 547-567, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34958137

RESUMO

Mouse embryonic stem cells (mESCs) are a widely used model for their diverse availability in studying early embryonic development and their application in regenerative treatment of various intractable diseases. Transient receptor potential melastatin 7 (Trpm7) regulates Ca2+ as a nonselective ion channel and is essential for early embryonic development; however, the precise role of Trpm7 in mESCs has not been clearly elucidated. In this study, we showed that the inhibition of Trpm7 affects the pluripotency and self-renewal of mESCs. We found that short hairpin RNA (shRNA)-mediated suppression of Trpm7 resulted in decreased expression of transcriptional regulators, Oct4 and Sox2, which maintain stemness in mESCs. In addition, Trpm7 knockdown led to alterations in the basic properties of mESCs, such as decreased proliferation, cell cycle arrest at the G0/G1 phase, and increased apoptosis. Furthermore, embryoid body (EB) formation and teratoma formation assays revealed abnormal regulation of differentiation due to Trpm7 knockdown, including the smaller size of EBs, elevated ectodermal differentiation, and diminished endodermal and mesodermal differentiation. We found that EB Day 7 samples displayed decreased intracellular Ca2+ levels compared to those of the scrambled group. Finally, we identified that these alterations induced by Trpm7 knockdown occurred due to decreased phosphorylation of mechanistic target of rapamycin (mTOR) and subsequent activation of extracellular signal-regulated kinase (ERK) in mESCs. Our findings suggest that Trpm7 could be a novel regulator for maintaining stemness and modulating the differentiation of mESCs.


Assuntos
Células-Tronco Embrionárias Murinas , Canais de Cátion TRPM , Animais , Diferenciação Celular , Proliferação de Células , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Camundongos , Células-Tronco Embrionárias Murinas/metabolismo , RNA Interferente Pequeno/metabolismo , Sirolimo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismo
13.
IEEE Trans Haptics ; 15(1): 200-211, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34529575

RESUMO

The objective of this paper is to develop and evaluate a directional vibrotactile feedback interface as a guidance tool for postural adjustments during work. In contrast to the existing active and wearable systems such as exoskeletons, we aim to create a lightweight and intuitive interface, capable of guiding its wearers towards more ergonomic and healthy working conditions. To achieve this, a vibrotactile device called ErgoTac is employed to develop three different feedback modalities that are able to provide a directional guidance at the body segments towards a desired pose. In addition, an evaluation is made to find the most suitable, comfortable, and intuitive feedback modality for the user. Therefore, these modalities are first compared experimentally on fifteen subjects wearing eight ErgoTac devices to achieve targeted arm and torso configurations. The most effective directional feedback modality is then evaluated on five subjects in a set of experiments in which an ergonomic optimisation module provides the optimised body posture while performing heavy lifting or forceful exertion tasks. The results yield strong evidence on the usefulness and the intuitiveness of one of the developed modalities in providing guidance towards ergonomic working conditions, by minimising the effect of an external load on body joints. We believe that the integration of such low-cost devices in workplaces can help address the well-known and complex problem of work-related musculoskeletal disorders.


Assuntos
Ergonomia , Vibração , Retroalimentação , Humanos , Postura , Tronco
14.
Life Sci ; 288: 120170, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34826438

RESUMO

AIMS: Antitumor effects of veratramine in prostate and liver cancers has been investigated, but it is still unclear whether veratramine can be used as an effective therapeutic agent for glioma. The aim of this study was to evaluate the potential pharmacological mechanism of veratramine in glioma. MAIN METHODS: Using four types of human glioblastoma cell lines, including A172, HS-683, T98G, and U-373-MG the dose-dependent antitumor effect of veratramine was evaluated. The cytotoxicity and cell proliferation were examined by CCK-8, and cell proliferation was further confirmed by anchorage-independent colony formation assay. The cell cycle distribution and apoptotic rate was assessed by flow cytometry, and apoptosis was further evaluated by apoptosis assay. The migration and invasiveness capacity were analyzed by using transwell. Protein and mRNA levels of related factors were determined by western blotting and RT-qPCR, respectively. KEY FINDINGS: Veratramine markedly induced apoptosis, suppressed the cell proliferation via the cell cycle G0/G1 phase arrest, and reduced the capacity for the migration and invasion in human glioblastoma multiforme cell lines. Moreover, veratramine was sufficient to affect the phosphatidylinositol-3-kinase/serine-threonine kinase/mechanistic target of rapamycin signaling pathway and its downstream Mdm2/p53/p21 pathway in human glioblastoma cell lines. SIGNIFICANCE: Antitumor effects of veratramine in suppression of glioma progression was mediated by the regulation of PI3K/Akt/mTOR and Mdm2/p53/p21 signaling pathway.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Alcaloides de Veratrum/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Ciclo Celular , Movimento Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Invasividade Neoplásica , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Serina-Treonina Quinases TOR/genética , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
15.
Front Psychol ; 13: 976102, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36710791

RESUMO

As the COVID-19 pandemic extends over a long period of time, the World Food Programme (WFP) estimated that food insecurity would take place in the near future. Previous studies focused on various kinds of interventions for food waste prevention. Surprisingly, however, research tackling consumer attitudes and behaviors as a way to reduce food waste is still rare. To fill this gap in the literature, this study examined the antecedent roles of restaurant customers' nature connection and biospheric values in fostering their food leftover reduction intention through environmental self-identity and sense of obligation to reduce food leftover. In addition, the moderating effects of gender were tested on all the relationships in our conceptual model. A quantitative approach with an online survey for restaurant customers was adopted. Structural equation modeling was adopted to analyze the data. Through confirmatory factor analyses, the adequate reliability and validity of the measures were established. All the relationships between the constructs were found to be significant, supporting the hypotheses. In other words, the restaurant customers' nature connection and biospheric values were found to eventually induce the customers' food leftover reduction intention. In addition, in terms of the moderating effect, the male customers' nature connection more strongly increased their biospheric values than the female customers' case. The findings of this study revealed how restaurant customers' food leftover reduction intention is formed through their feeling of oneness with nature and biospheric values. Given that consumer behavior has been recognized as a major driver of restaurant food waste, the findings of this study provide useful insights to restauranteurs and policymakers for the health of society and people in it. It was especially true for men in that their feeling of oneness with nature significantly influences their biospheric values more than women's.

16.
Sensors (Basel) ; 21(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34300542

RESUMO

Machine vision with deep learning is a promising type of automatic visual perception for detecting and segmenting an object effectively; however, the scarcity of labelled datasets in agricultural fields prevents the application of deep learning to agriculture. For this reason, this study proposes weakly supervised crop area segmentation (WSCAS) to identify the uncut crop area efficiently for path guidance. Weakly supervised learning has advantage for training models because it entails less laborious annotation. The proposed method trains the classification model using area-specific images so that the target area can be segmented from the input image based on implicitly learned localization. This way makes the model implementation easy even with a small data scale. The performance of the proposed method was evaluated using recorded video frames that were then compared with previous deep-learning-based segmentation methods. The results showed that the proposed method can be conducted with the lowest inference time and that the crop area can be localized with an intersection over union of approximately 0.94. Additionally, the uncut crop edge could be detected for practical use based on the segmentation results with post-image processing such as with a Canny edge detector and Hough transformation. The proposed method showed the significant ability of using automatic perception in agricultural navigation to infer the crop area with real-time level speed and have localization comparable to existing semantic segmentation methods. It is expected that our method will be used as essential tool for the automatic path guidance system of a combine harvester.


Assuntos
Processamento de Imagem Assistida por Computador , Aprendizado de Máquina Supervisionado , Agricultura , Semântica
17.
J Org Chem ; 86(22): 15973-15991, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34185997

RESUMO

Oxidation potential-guided electrochemical radical-radical cross-coupling reactions between N-heteroarenes and sodium sulfinates have been established. Thus, simple cyclic voltammetry measurement of substrates predicts the likelihood of successful radical-radical coupling reactions, allowing the simple and direct synthetic access to 3-sulfonylated imidazopyridines and indolizines. The developed electrochemical radical-radical cross-coupling reactions to sulfonylated N-heteroarenes boast the green synthetic nature of the reactions that are oxidant- and metal-free.

18.
Sensors (Basel) ; 21(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799875

RESUMO

The objective of this study was to develop a model to estimate the axle torque (AT) of a tractor using an artificial neural network (ANN) based on a relatively low-cost sensor. ANN has proven to be useful in the case of nonlinear analysis, and it can be applied to consider nonlinear variables such as soil characteristics, unlike studies that only consider tractor major parameters, thus model performance and its implementation can be extended to a wider range. In this study, ANN-based models were compared with multiple linear regression (MLR)-based models for performance verification. The main input data were tractor engine parameters, major tractor parameters, and soil physical properties. Data of soil physical properties (i.e., soil moisture content and cone index) and major tractor parameters (i.e., engine torque, engine speed, specific fuel consumption, travel speed, tillage depth, and slip ratio) were collected during a tractor field experiment in four Korean paddy fields. The collected soil physical properties and major tractor parameter data were used to estimate the AT of the tractor by the MLR- and ANN-based models: 250 data points were used for developing and training the model were used, the 50 remaining data points were used to test the model estimation. The AT estimated with the developed MLR- and ANN-based models showed agreement with actual measured AT, with the R2 value ranging from 0.825 to 0.851 and from 0.857 to 0.904, respectively. These results suggest that the developed models are reliable in estimating tractor AT, while the ANN-based model showed better performance than the MLR-based model. This study can provide useful results as a simple method using ANNs based on relatively inexpensive sensors that can replace the existing complex tractor AT measurement method is emphasized.

19.
Artigo em Inglês | MEDLINE | ID: mdl-35010275

RESUMO

Climate change is certainly a global problem that negatively affects all nations, and thus all humans, on the globe. Nevertheless, little is known about people's perceptions of climate change and its effects on people's attitudinal and behavioral responses to climate change. The present study successfully addressed how hotel guests' environment-friendly behavior intention is formed through their self-perception as a member of the global community and their psychological distance of climate change. An online survey was used to collect quantitative data from hotel guests to verify the hypotheses. Our test results supported all the hypotheses in our conceptual model. Consequently, the findings of this study satisfactorily explained how hotel guests form their intention to engage in environment-friendly behaviors while they are staying at hotels.


Assuntos
Mudança Climática , Intenção , Humanos , Distância Psicológica , Autoimagem , Inquéritos e Questionários
20.
Sensors (Basel) ; 20(24)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33353195

RESUMO

The objective of this study is the simulation of the most affected design factors and variables of the clutch pack for the power-shift transmission (PST) of a tractor based measured data. The simulation model, the mathematical model of sliding velocity, a moment of inertia, and clutch engagement pressure of clutch pack were developed using the powertrain and configurations of the real PST tractor. In this study, the sensor fusion method was used to precisely measure the proportional valve pressure by test bench, which was applied to the simulation model. The clutch engagement times were found 1.20 s at all temperatures for determined factors. The engagement pressures have a significant difference at various temperatures (25 to 100 °C) of the hydraulic oils after the 1.20 s but the most affected factors were satisfied with the simulation conditions that ensure the clutch engagement on time. Finally, this sensor fusion method is believed to be helpful in realizing precision agriculture through minimization of power loss and maximum energy efficiency of tractors.

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