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1.
Materials (Basel) ; 16(20)2023 Oct 23.
Article in English | MEDLINE | ID: mdl-37895802

ABSTRACT

As the demand for the development and utilization of marine resources continues to strengthen, the service requirements for advanced marine equipment are rapidly increasing. Surface protection technology has become an important way of solving the tribological problems of extreme operating conditions and improving the safety performance of equipment by imparting certain special properties to the surface of the material through physical, chemical or mechanical processes to enhance the ability of the material to withstand external environmental factors. Combined with the extremely complex characteristics of the marine environment, this paper describes the commonly used surface protection technologies for metal materials in the marine environment. Research on surface texture was summarized under different surface reshaping technologies, as well as processes and coating materials under different surface modification technologies. Combined with the existing research progress and development trends of marine metallic materials, the surfaces of metal materials under the marine environment protection technology foreground are prospected and provide a reference for the improvement of equipment performance in extreme marine environments.

2.
Front Immunol ; 14: 1109352, 2023.
Article in English | MEDLINE | ID: mdl-36817424

ABSTRACT

Regulatory T (Treg) cells could be divided into thymus-derived Treg (tTreg) cells and peripherally derived Treg (pTreg) cells, and in vitro induced Treg (iTreg) cells. To date, the functions of tTreg versus pTreg and their relative contributions to maternal-fetal immune tolerance remain insufficiently defined due to a lack of a specific marker to distinguish tTreg cells from pTreg cells. In this study, we investigated the role of thymus- and extrathymus-derived Treg cells in pregnancy tolerance using transgenic ACT-mOVA, Foxp3DTR and Foxp3GFP mice, and Treg cell adoptive transfer, etc. We found that the frequencies of Treg cells in the thymus, spleen and lymph nodes (LNs) in either syngeneically- or allogeneically-mated pregnant mice were not different from non-pregnant mice. However, percentages of blood Treg cells in pregnant mice increased at mid-gestation, and percentages of decidua Treg cells in pregnant mice increased as the pregnancy progressed compared with non-pregnant mice, and were significantly higher in allogeneic mice than those in syngeneic group. Compared with syngeneic mice, levels of CCR2 and CCR6 on blood and decidua Treg cells and CCL12 in the decidua significantly increased in allogeneic mice. A surrogate fetal antigen mOVA that was recognized by naïve T cells from OT-IIFoxp3GFP mice induced the generation of pTreg cells in vivo. Transfusion of thymus and spleen Treg cells significantly decreased diphtheria toxin (DT)-increased embryo resorption rates (ERRs) and IFN-γ levels in the blood and decidua. iTreg cells also decreased ERRs and IFN-γ levels in the blood and decidua to an extent lower than thymus and spleen Treg cells. In conclusion, increased blood and decidua Treg cells in pregnancy and increased ERRs in DT-treated Foxp3DTR mice suggest an important immunosuppressive role of Treg cells in pregnancy. Elevated decidua Treg cells in pregnancy could be derived from the recruitment of tTreg cells to the decidua, or from the transformation of naïve T cells in the decidua to pTreg cells. While the immune-suppression effects of thymus and spleen Treg cells are comparable, iTreg cells might play a weaker role in maternal-fetal tolerance.


Subject(s)
Immune Tolerance , T-Lymphocytes, Regulatory , Pregnancy , Female , Mice , Animals , Spleen , Immunosuppression Therapy , Forkhead Transcription Factors
3.
Front Microbiol ; 13: 1059227, 2022.
Article in English | MEDLINE | ID: mdl-36569048

ABSTRACT

The gut microbiota undergoes dynamic changes during pregnancy. The gut microbial and metabolic networks observed in pregnant women have not been systematically analyzed. The primary purpose of this study was to explore the alterations in the gut microbiota and metabolism during late pregnancy and investigate the associations between the gut microbiota and metabolism. A total of thirty healthy pregnant women were followed from 30 to 32 weeks of gestation to full term. Fecal samples were collected for microbiome analysis and untargeted metabolomic analysis. The characteristics of the gut microbiota were evaluated by 16S ribosomal RNA gene sequencing of the V3-V4 regions. The plasma samples were used for untargeted metabolomic analysis with liquid chromatography-tandem mass spectrometry. The interplay between the gut microbiota and metabolism was analyzed further by bioinformatics approaches. We found that the relative abundances of Sellimonas and Megamonas were higher at full term, whereas that of Proteobacteria was lower. The correlation network of the gut microbiota tended to exhibit weaker connections from 32 weeks of gestation to the antepartum timepoint. Changes in the gut microbiota during late pregnancy were correlated with the absorbance and metabolism of microbiota-associated metabolites, such as fatty acids and free amino acids, thereby generating a unique metabolic system for the growth of the fetus. Decreasing the concentration of specific metabolites in plasma and increasing the levels of palmitic acid and 20-hydroxyarachidonic acid may enhance the transformation of a proinflammatory immune state as pregnancy progresses.

4.
Opt Express ; 30(18): 33022-33034, 2022 Aug 29.
Article in English | MEDLINE | ID: mdl-36242352

ABSTRACT

This paper presents an absolute phase unwrapping method for high-speed three-dimensional (3D) shape measurement. This method uses three phase-shifted patterns and one binary random pattern on a single-camera, single-projector structured light system. We calculate the wrapped phase from phase-shifted images and determine the coarse correspondence through the digital image correlation (DIC) between the captured binary random pattern of the object and the pre-captured binary random pattern of a flat surface. We then developed a computational framework to determine fringe order number pixel by pixel using the coarse correspondence information. Since only one additional pattern is used, the proposed method can be used for high-speed 3D shape measurement. Experimental results successfully demonstrated that the proposed method can achieve high-speed and high-quality measurement of complex scenes.

5.
Sensors (Basel) ; 23(1)2022 Dec 30.
Article in English | MEDLINE | ID: mdl-36617015

ABSTRACT

Measuring speed is a critical factor to reduce motion artifacts for dynamic scene capture. Phase-shifting methods have the advantage of providing high-accuracy and dense 3D point clouds, but the phase unwrapping process affects the measurement speed. This paper presents an absolute phase unwrapping method capable of using only three speckle-embedded phase-shifted patterns for high-speed three-dimensional (3D) shape measurement on a single-camera, single-projector structured light system. The proposed method obtains the wrapped phase of the object from the speckle-embedded three-step phase-shifted patterns. Next, it utilizes the Semi-Global Matching (SGM) algorithm to establish the coarse correspondence between the image of the object with the embedded speckle pattern and the pre-obtained image of a flat surface with the same embedded speckle pattern. Then, a computational framework uses the coarse correspondence information to determine the fringe order pixel by pixel. The experimental results demonstrated that the proposed method can achieve high-speed and high-quality 3D measurements of complex scenes.

6.
Environ Sci Pollut Res Int ; 28(42): 59665-59672, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34142322

ABSTRACT

The red imported fire ant is one of the world's most devastating invasive species, adversely affecting humans, wildlife, crops, and livestock. To control infestations, chemical pesticides are deployed extensively around the world. However, their extensive use has led to negative effects on the environment and human health. Essential oils, which are safe and ecofriendly, can potentially be used as alternatives to chemical pesticides. In this study, grapefruit essential oils were used as fumigant agents to control red imported fire ants. The crude grapefruit oil (GO1) contained 28 compounds, and the concentrated grapefruit oil (GO2), which was refined from GO1 by vacuum distillation, contained 20 compounds. D-Limonene was the dominant constituent in both GO1 (70.1%) and GO2 (73.96%), and other important constituents included ß-pinene, α-pinene, ß-phellandrene, octanal, d-carvone, α-terpineol, and linalool. Both the essential oils and their individual constituents (α-pinene, α-terpineol, ß-phellandrene, octanal, and d-carvone) showed strong lethal fumigant effects against workers. Workers were more susceptible to GO2 than GO1, and octanal was more toxic to workers as compared with the other four constituents. When antennas of workers were treated with the two oils or the five constituents, their walking and gripping abilities were significantly suppressed, and there was an obvious bending or breaking phenomenon on the sensilla of the antennas. Fumigant activity by grapefruit essential oils and their main compounds were associated with their effects on the walking and gripping behavior of workers, and this confirmed that grapefruit essential oil is a promising, ecofriendly, and safe fumigant for the control of red imported fire ants.


Subject(s)
Ants , Citrus paradisi , Oils, Volatile , Pesticides , Animals , Plant Oils
7.
J Econ Entomol ; 114(3): 1219-1225, 2021 06 11.
Article in English | MEDLINE | ID: mdl-33885770

ABSTRACT

The insecticides of microbial origin may be promising biocontrol agents to control pests. In this study, a major metabolite was extracted and purified from Serratia marcescens KH-001 and identified as prodigiosin with a molecule weight of 324.2094, and our primary aim was to evaluate the effects of prodigiosin against Diaphorina citri Kuwayama (Hemiptera: Liviidae) in the laboratory and in the field. Toxicity of purified prodigiosin to nymphs increased with increasing temperature from 25 to 35°C. The laboratory experiment results observed inhibition effects of purified prodigiosin at LC50 on oviposition and egg hatch of D. citri at 30°C. Furthermore, adults that fed on citrus leaves treated with LC20 and LC50 solution of purified prodigiosin at 30°C excreted less honeydew (28-35%) compared with controls, suggesting moderate antifeedant activity of prodigiosin. The results of field experiment showed that 10% prodigiosin emulsifiable concentrate exhibited better control efficacy (70-100%) at three concentrations (100, 200, and 500 mg/liter) in July and August than in October. These data indicate that prodigiosin will be a highly effective compound for the control of D. citri depending on the prevailing temperature conditions and may become a commercially available product to be widely used in citrus orchards.


Subject(s)
Citrus , Hemiptera , Animals , Female , Nymph , Prodigiosin , Serratia marcescens
8.
J Forensic Sci ; 66(1): 112-128, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33034904

ABSTRACT

The forensic science community raised the need for improved evidence recognition, collection, and visualization analytical instrumentation for field and laboratory use. While the 3D optical techniques for imaging static objects have been extensively studied, there is still a major gap between current knowledge and collecting high-quality footwear and tire impression evidence. Among optical means for 3D imaging, digital fringe projection (DFP) techniques reconstruct 3D shape from phase information, achieving camera-pixel spatial resolution. This paper presents a high-resolution 3D imaging technology using DFP techniques dedicated to footwear and tire impression capture. We developed fully automated software algorithms and a graphical user interface (GUI) that allow anyone without training to operate for high-quality 3D data capture. We performed accuracy evaluations and comparisons comparing with the commercial high-end 3D scanner and carried out qualitative tests for various impressions comparing with the current practices. Overall, our technology achieves similar levels of accuracy and resolution with a high-end commercially available 3D scanner, while having the merits of being (1) more affordable; (2) much easier to operate; and (3) more robust. Compared with the current practice of casting, our technology demonstrates its superiority because it (1) is non-destructive; (2) collects more evidence detail than casts, especially when an impression is fragile; (3) requires less time and money to collect each piece of evidence; and (4) results in a digital file that can easily be shared with other examiners.

9.
Fish Physiol Biochem ; 45(1): 43-61, 2019 Feb.
Article in English | MEDLINE | ID: mdl-29980882

ABSTRACT

Firstly, a linoleic and linolenic acid emulsion and fish feeds were incubated with graded levels of ethoxyquin (EQ) and petroleum ether extract, ethyl acetate extract (EAE), ethanol extract and aqueous extract of Angelica sinensis. The results showed that EQ and extracts of Angelica sinensis (EAs) inhibited lipid oxidation in material above. Of all of the examined EAs, EAE showed the strongest protective effects against the lipid oxidation. Moreover, EAE at high concentrations showed a stronger inhibitory effect on lipid oxidation than that of EQ. Next, 7 experimental diets that respectively supplemented 0.0, 0.2, 0.8 and 3.2 g kg-1 of EQ and EAE were fed to 280 juvenile red carp (Cyprinus carpio var. xingguonensis) with seven treatment groups for 30 days. The results indicated that dietary EAE improved growth performance in carp. Moreover, dietary EAE increased the activities of trypsin, lipase, alpha-amylase, alkaline phosphatase, glutamate-oxaloacetate transaminase and glutamate-pyruvate transaminase (GPT) and decreased plasma ammonia content in carp. Meanwhile, dietary EAE reduced the levels of malondialdehyde and raised the activities of anti-superoxide anion, anti-hydroxyl radical, superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase and the content of reduced glutathione in the hepatopancreas and intestine of carp. However, with the exception of GPT, dietary EQ got the opposite results to dietary EAE in carp. These results revealed that dietary EAE improved the digestive, absorptive and antioxidant capacities in fish. However, dietary EQ inhibited the digestive, absorptive and antioxidant capacities in fish. So, EAE could be used as a natural antioxidant for replacing EQ in fish feeds.


Subject(s)
Angelica sinensis/chemistry , Animal Feed/analysis , Carps/growth & development , Ethoxyquin/pharmacology , Lipid Peroxidation/drug effects , Plant Extracts/pharmacology , Animal Nutritional Physiological Phenomena , Animals , Antioxidants/metabolism , Diet/veterinary , Digestion/drug effects , Gene Expression Regulation/drug effects , Plant Extracts/chemistry , Random Allocation
10.
Bing Du Xue Bao ; 32(6): 727-32, 2016 11.
Article in Chinese | MEDLINE | ID: mdl-30004204

ABSTRACT

We studied the molecular epidemiology of echovirus 30 in sporadic cases of viral encephalitis in Longyan City, Fujian, China, from 2011 to 2014.Specimens of cerebrospinal fluid from patients diagnosed with viral encephalitis or infection of the central nervous system were collected. Viruses were isolated by cell culture. Identification of the echovirus 30 serotype and genetic analyses were undertaken. Amplification of virus protein(VP)-1gene sequences was done by reverse transcription-polymerase chain reaction. A total of 168 strains of enterovirus were isolated in 608 cases from 2011 to 2014,of which 60 strains were echovirus 30.The epidemic "peak" of echovirus 30 was from June to August. The age range of patients was wide, with 65% of cases under 10 years of age. Clinical manifestations were pyrexia, headache and vomiting.Cerebrospinal fluid was clear, and the number of cells and protein was increased. The epidemic strains in Longyan City from 2011 to 2014belonged to the "h" genotype, and there were two transmission chains. Compared with the viral encephalitis strains from the outbreak in Fujian Province in 2011,they were highly homologous, but a new amino-acid variation of VP1 protein I 120 V was found in Longyan City strains from 2014.The viral encephalitis strains from the outbreak in Fujian Province in 2011 were present in Longyan City strains, and two transmission chains are still circulating,but there were new mutations in the virus strains from 2014.Continuous monitoring will aid:(i)early detection of viral variants that may accumulate;(ii)assessment of the risk of epidemics.


Subject(s)
Echovirus Infections/virology , Enterovirus B, Human/genetics , Enterovirus B, Human/isolation & purification , Adolescent , Adult , Aged , Child , Child, Preschool , China/epidemiology , Echovirus Infections/epidemiology , Enterovirus B, Human/classification , Enterovirus B, Human/metabolism , Female , Genotype , Humans , Infant , Male , Middle Aged , Molecular Epidemiology , Phylogeny , Viral Proteins/genetics , Viral Proteins/metabolism , Young Adult
11.
Bing Du Xue Bao ; 31(1): 36-41, 2015 Jan.
Article in Chinese | MEDLINE | ID: mdl-25997328

ABSTRACT

This study aimed to analyse the genetically characterize isolates of Echovirus 11 from Longyan City,Fujian Province,and to reveal their genetic relationships with other isolates from China and abroad. Cerebrospinal fluid specimens from patients diagnosed with viral encephalitis or central nervous system (CNS) infections were collected from Longyan First Hospital between January and December 2011. Seven Echo11 strains were isolated and identified using the RIMV serum panel. The entire VP1 coding regions of four strains were sequenced and typed as Echo11 by an online blast program and,subsequently, phylogenet- ic analyses of the VP1 sequences of these stains and others published on GenBank were conducted. There were 600 nucleotides (nt) in each complete VP1 coding region that encoded 200 amino acids (aa). Among those four Echo11 strains, the sequence identities of nt and aa were 100% and 99%-100% respectively. And phylogenetic analyses indicate belong to subtype DS, the homology compared with DS strain (GU393713) were 93% (nt) and 99% (aa). The sequence identities for the nt and aa were 75%-76% and 90%, respectively, between the current isolates from Longyan and the Gregory prototype strain found in 1953. The sequence identity of nt and aa between the Longyan virus strains and the domestic Shandong strains isolated in 2010 were lower, at 74% and 88%-89%, respectively. However,the highest level of ho- mology was found when the Longyan strains were compared with the Netherlands strain (GU393773) found in 2007 (nt and aa identity: 94%-95% and 98%-99%, respectively). The relatively low levels of similarity between domestic isolates suggest that different transmission routes exist for Echo11 in mainland China.


Subject(s)
Encephalitis, Viral/virology , Enterovirus B, Human/genetics , Enterovirus B, Human/isolation & purification , Enterovirus Infections/virology , Adolescent , Amino Acid Sequence , Base Sequence , Child , Child, Preschool , Chin , China , Enterovirus B, Human/chemistry , Enterovirus B, Human/classification , Female , Genotype , Humans , Male , Middle Aged , Molecular Sequence Data , Phylogeny , Sequence Alignment , Viral Proteins/chemistry , Viral Proteins/genetics
12.
Bing Du Xue Bao ; 30(4): 412-6, 2014 Jul.
Article in Chinese | MEDLINE | ID: mdl-25272596

ABSTRACT

This study aimed to analyze the etiology of the encephalitis outbreak in Longyan, Fujian Province, China in 2010, in order to provide valuable information for this prevention and control of this disease. Pathogens were confirmed from cerebrospinal fluid samples with fluorescent RT-PCR, virus isolation (RD cells), and neutralization tests. Then, the VP1 fragments or whole genome nucleotide sequences were determined for four virus strains using PCR. Homology was assessed using the MegAlign software, and a phylogenetic evolutionary tree was drawn using Mega 4.0 software. The results confirmed that the etiology of the outbreak was the ECHO6 intestinal virus, and the nucleotide sequence of the VP1 segment indicated that the C2 subtype was responsible. The genome sequence consisted of 7407 nucleotides, and resembled the genome of other ECHO and CoxB viruses with homology levels of 78.5%-87.3%. The encephalitis outbreak in Longyan in 2010 was caused by the ECHO6 C2 subtype intestinal virus, and its complete genome sequence length is similar to the standard strain (U16283) with a sequence homology of 80.4%.


Subject(s)
Echovirus 6, Human/genetics , Echovirus 6, Human/isolation & purification , Echovirus Infections/epidemiology , Echovirus Infections/virology , Encephalitis/epidemiology , Encephalitis/virology , Child, Preschool , China/epidemiology , Disease Outbreaks , Echovirus 6, Human/classification , Female , Humans , Infant , Male , Molecular Sequence Data , Phylogeny
13.
Opt Express ; 22(5): 5357-74, 2014 Mar 10.
Article in English | MEDLINE | ID: mdl-24663876

ABSTRACT

This study details a one-time ray-tracing optimization method for the optimization of LED illumination systems [S.-C. Chu and H.-L. Yang, "One-time ray-tracing method for the optimization of illumination system," in Proceedings of International Conference on Optics in Precision Engineering and Nanotechnology (icOPEN, 2013), 87692M]. This method optimizes the performance of illumination systems by modifying the light source's radiant intensity distribution with a freeform lens, instead of modifying the illumination system structure. Because illumination system structures are unchanged in the design process, a designer can avoid the common problems faced when designing illumination systems, i.e., the repeated and time-consuming ray-tracing process when optimizing the illumination system parameters. The easy approaches of the proposed optimization method to sample the target illumination areas and to divide the light source radiant intensity distribution make the proposed method can be applied to both direct-lit and non-direct-lit illumination systems. To demonstrate the proposed method, this study designs an illuminator for a tube photo-bioreactor using the proposed one-time ray-tracing method. A comparison shows that in the designing of the photo-bioreactor, tracing all rays one time requires about 13 hours, while optimizing the light source's radiant intensity distribution requires only about twenty minutes. The considerable reduction in the ray-tracing time shows that the proposed method is a fast and effective way to design illumination systems.

14.
Opt Lett ; 33(5): 467-9, 2008 Mar 01.
Article in English | MEDLINE | ID: mdl-18311294

ABSTRACT

The polarization state of light is modulated by an anisotropic thin film. An anisotropic MgF(2) film is deposited onto a plate that is put in contact with a BK7 prism to form a BK7 prism/film/air configuration. It is shown that the polarization state of reflected light can be easily modulated from a linear state to a circular state by rotating the thin-film plate.

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