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1.
Sensors (Basel) ; 23(19)2023 Sep 22.
Article in English | MEDLINE | ID: mdl-37836857

ABSTRACT

This study is the first to develop technology to evaluate the object recognition performance of camera sensors, which are increasingly important in autonomous vehicles owing to their relatively low price, and to verify the efficiency of camera recognition algorithms in obstruction situations. To this end, the concentration and color of the blockage and the type and color of the object were set as major factors, with their effects on camera recognition performance analyzed using a camera simulator based on a virtual test drive toolkit. The results show that the blockage concentration has the largest impact on object recognition, followed in order by the object type, blockage color, and object color. As for the blockage color, black exhibited better recognition performance than gray and yellow. In addition, changes in the blockage color affected the recognition of object types, resulting in different responses to each object. Through this study, we propose a blockage-based camera recognition performance evaluation method using simulation, and we establish an algorithm evaluation environment for various manufacturers through an interface with an actual camera. By suggesting the necessity and timing of future camera lens cleaning, we provide manufacturers with technical measures to improve the cleaning timing and camera safety.

2.
Sensors (Basel) ; 23(5)2023 Mar 02.
Article in English | MEDLINE | ID: mdl-36904952

ABSTRACT

Autonomous driving includes recognition, judgment, and control technologies, and is implemented using sensors such as cameras, LiDAR, and radar. However, recognition sensors are exposed to the outside environment and their performance may deteriorate because of the presence of substances that interfere with vision, such as dust, bird droppings, and insects, during operation. Research on sensor cleaning technology to solve this performance degradation has been limited. This study used various types and concentrations of blockage and dryness to demonstrate approaches to the evaluation of cleaning rates for selected conditions that afford satisfactory results. To determine the effectiveness of washing, the study used the following criteria: washer, 0.5 bar/s and air, 2 bar/s, with 3.5 g being used three times to test the LiDAR window. The study found that blockage, concentration, and dryness are the most important factors, and in that order. Additionally, the study compared new forms of blockage, such as those caused by dust, bird droppings, and insects, with standard dust that was used as a control to evaluate the performance of the new blockage types. The results of this study can be used to conduct various sensor cleaning tests and ensure their reliability and economic feasibility.

3.
Cell Rep ; 39(2): 110657, 2022 04 12.
Article in English | MEDLINE | ID: mdl-35417681

ABSTRACT

It remains unclear how the pro-immunogenic maturation of conventional dendritic cells (cDCs) abrogates their tolerogenic functions. Here, we report that the loss of tolerogenic functions depends on the rapid death of BTLAhi cDC1s, which, in the steady state, are present in systemic peripheral lymphoid organs and promote tolerance that limits subsequent immune responses. A canonical inducer of maturation, lipopolysaccharide (LPS), initiates a burst of tumor necrosis factor alpha (TNF-α) production and the resultant acute death of BTLAhi cDC1s mediated by tumor necrosis factor receptor 1. The ablation of these individual tolerogenic cDCs is amplified by TNF-α produced by neighboring cells. This loss of tolerogenic cDCs is transient, accentuating the restoration of homeostatic conditions through biological turnover of cDCs in vivo. Therefore, our results reveal that the abrogation of tolerogenic functions during an acute immunogenic maturation depends on an ablation of the tolerogenic cDC population, resulting in a dynamic remodeling of the cDC functional landscape.


Subject(s)
Dendritic Cells , Tumor Necrosis Factor-alpha , Immune Tolerance , Lipopolysaccharides/pharmacology
4.
Biomed Opt Express ; 10(5): 2430-2445, 2019 May 01.
Article in English | MEDLINE | ID: mdl-31149378

ABSTRACT

Super-resolution optical fluctuation imaging (SOFI) offers a simple and affordable alternative to other super-resolution (SR) imaging techniques. The theoretical resolution enhancement of SOFI scales linearly with the order of cumulants, while the imaging conditions exhibit less photo-toxicity to the living samples as compared to other SR methods. High order SOFI could, therefore, be a method of choice for dynamic live cell imaging. However, due to the cusp-artifacts and dynamic range expansion of pixel intensities, this promise has not been materialized as of yet. Here we investigated and compared high order moments vs. high order cumulant SOFI reconstructions. We demonstrate that even-order moments reconstructions are intrinsically free of cusp artifacts, allowing for a subsequent deconvolution operation to be performed, hence enhancing the resolution even further. High order moments reconstruction performance was examined for various (simulated) conditions and applied to (experimental) imaging of QD labeled microtubules in fixed cells, and actin stress fiber dynamics in live cells.

5.
Microb Pathog ; 125: 486-492, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30342080

ABSTRACT

This study aimed to isolate and demonstrate their antioxidant and immunostimulatory activities of potential probiotics. The isolated strains, S. Pum19, SC28, and SC61 showed potential probiotic properties including stability in artificial gastric and bile conditions, non-production of ß-glucuronidase, suitable antibiotic susceptibility, and attachment to intestinal cells. S. Pum19, SC28, and SC61 strains were identified as Leuconostoc citreum, Pediococcus pentosaceus, and Lactobacillus paraplantarum, respectively. Of the 3 potential probiotic LAB strains, intact cells of L. paraplantarum SC61 showed higher antioxidant activity, including DPPH radical scavenging, ß-carotene bleaching inhibition, reducing power, superoxide anion scavenging, and ABTS radical scavenging activity. In addition, L. paraplantarum SC61 produced the most nitric oxide production and its mRNA expression level for iNOS, IL-1ß, IL-6, and TNF-α were superior to those of L. rhamnosus GG. Therefore, L. paraplantarum SC61 was demonstrated to exhibit antioxidant and immunostimulatory activity and to have potential use as a probiotic product.


Subject(s)
Antioxidants/metabolism , Fermented Foods/microbiology , Immunologic Factors/metabolism , Lactobacillus/isolation & purification , Lactobacillus/metabolism , Probiotics/isolation & purification , Probiotics/pharmacology , Bile Acids and Salts/metabolism , Biphenyl Compounds/metabolism , Free Radical Scavengers/isolation & purification , Free Radical Scavengers/pharmacology , Korea , Microbial Sensitivity Tests , Microbial Viability/drug effects , Picrates/metabolism , Superoxides/metabolism
6.
Food Sci Biotechnol ; 27(1): 123-129, 2018 Feb.
Article in English | MEDLINE | ID: mdl-30263732

ABSTRACT

This study was designed to isolate lactic acid bacteria (LAB) with ß-glucosidase activity and probiotic properties from Korean fermented foods. Among nine isolates, four LAB strains had excellent survival rates at pH 2.5 with 0.3% (w/v) pepsin for 3 h and 0.3% (w/v) oxgall for 24 h. Four LAB strains did not produce ß-glucuronidase and showed adhesion ability to HT-29 cells that was superior to that shown by the reference strain Lactobacillus rhamnosus GG. All four strains were sensitive to ampicillin, tetracycline, chloramphenicol, and doxycycline. These strains were identified as Leuconostoc mesenteroides H40, Lactobacillus plantarum FI10604, L. brevis FI10700, and L. perolens FI10842 by 16S rRNA gene sequence, respectively. It was found that L. perolens FI10842 produced the highest ß-glucosidase activity (49.10 mU/mL). These results indicate that the four LAB strains could be used as potential probiotic. Especially L. perolens FI10842 could be used as a starter culture for fermentation.

7.
Microb Pathog ; 112: 135-141, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28963009

ABSTRACT

This study aimed at evaluating the functional and probiotic properties of three lactic acid bacterial (LAB) strains isolated from kimchi. The selected LAB strains, which had potential probiotic functions, were identified by 16S rRNA sequence analysis as Lactobacillus brevis G1, L. brevis KU15006, and Lactobacillus curvatus KCCM 200173. All LAB strains were able to tolerate incubation at pH 2.5 with 0.3% pepsin for 3 h and with 0.3% Oxgall for 24 h and showed similar enzyme production levels, antimicrobial activities, and antibiotic susceptibilities. L. brevis G1 and KU15006 presented higher adhesion ability, auto-aggregation, and cell surface hydrophobicity than Lactobacillus rhamnosus KCTC 12202BP, a commercial strain used as positive control. All LAB strains showed 50-60% co-aggregation activity with selected foodborne pathogens. L. brevis KU15006 showed anti-adhesion activity against Escherichia coli and Salmonella Typhimurium. In addition, cell-free supernatant and cell-free extract from L. brevis KU15006 displayed the highest inhibitory activities against α-glucosidase. These results indicate that L. brevis KU15006 has the best properties, with pathogen antagonistic and antidiabetic activity, for use in probiotic products.


Subject(s)
Bacterial Adhesion , Fermented Foods/microbiology , Foodborne Diseases/therapy , Hypoglycemic Agents , Levilactobacillus brevis/isolation & purification , Levilactobacillus brevis/physiology , Probiotics , Acclimatization , Adhesins, Bacterial , Adhesins, Escherichia coli , Anti-Infective Agents/metabolism , Anti-Infective Agents/pharmacology , Antibiosis/physiology , Bile Acids and Salts , Caco-2 Cells , Enzyme Activation , Humans , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Lactobacillus/genetics , Levilactobacillus brevis/classification , Levilactobacillus brevis/genetics , Microbial Sensitivity Tests , RNA, Ribosomal, 16S/genetics , Salmonella typhimurium , Sequence Analysis , Species Specificity , alpha-Glucosidases
8.
Food Sci Biotechnol ; 25(4): 1129-1133, 2016.
Article in English | MEDLINE | ID: mdl-30263385

ABSTRACT

Lactobacillus plantarum Lb41 was determined probiotic properties and applied to cottage cheese. L. plantarum Lb41 showed high viability (>80%) in artificial gastric (pH 2.5, 0.3% pepsin for 3 h) and bile (0.3% oxgall for 24 h) acids, and adhered strongly to HT-29 cells (7.5% adhesion). It did not produce ß-glucuronidase and was resistant to several antibiotics. L. plantarum Lb41 did not inhibit proliferation of normal MRC-5 cells, but showed antiproliferative effects on AGS, HT-29, and LoVo cells, based on 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. In addition, L. plantarum Lb41 reduced nitric oxide production by macrophages. Cottage cheese containing this strain did not show significant differences in physicochemical properties, but the number of lactic acid bacteria was maintained longer than that in control cheese. These results indicate that L. plantarum Lb41 could potentially be used as a probiotic in foods.

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