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1.
Plant Pathol J ; 40(3): 329-335, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38835304

RESUMO

Phytophthora root and stem rot (PRR), caused by Phytophthora sojae, can occur at any growth stage under poorly drained and humid conditions. The expansion of soybean cultivation in South Korean paddy fields has increased the frequency of PRR outbreaks. This study aimed to identify four P. sojae isolates newly collected from domestic fields and evaluate race-specific resistance using the hypocotyl inoculation technique. The four isolates exhibited various pathotypes, with GJ3053 exhibiting the highest virulence complexity. Two isolates, GJ3053 and AD3617, were screened from 205 soybeans, and 182 and 190 genotypes (88.8 and 92.7%, respectively) were susceptible to each isolate. Among these accessions, five genotypes resistant to both isolates were selected. These promising genotypes are candidates for the development of resistant soybean cultivars that can effectively control PRR through gene stacking.

2.
Langmuir ; 40(19): 10098-10106, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38696820

RESUMO

Our research investigates the impact of auxiliary structures on ion transport in electrochemical systems such as batteries and microscale desalination units, whose importance for sustainable development has increased dramatically in recent decades. The electrochemical systems typically feature ion-selective surfaces, such as electrodes and ion exchange membranes, where ion depletion can cause performance issues including metal dendrite formation and flow instability. Recent research has shown that auxiliary structures in these electrochemical systems can enhance ion transfer near ion-selective surfaces, thereby resolving the instability problem and improving the energy conversion efficiency of the system. Our study leverages recent advancements in nanoscale electrokinetics to model these auxiliary structures as pillar arrays near an ion exchange membrane in a microchannel. We examine how these structures enhance ion transports relative to the characteristic length scale of microchannel depth and pillars' proximity to the ion-selective surface. Results show that the effect of the pillars varies significantly with their placement. Specifically, in deeper microchannels, where electrokinetic convection is stronger, the closer the auxiliary structure is to the ion-selective membrane, the better the ion transfer. However, in the thinner microchannel, the proximity of the auxiliary structure to the ion selective membrane has a less significant correlation with the ion transfer. Therefore, this finding highlights the importance of spatial arrangement of the auxiliary structures in improving the performance of electrochemical devices. Conclusively, this study can help to better understand energy conversion systems such as fuel cells, salinity gradient power generation systems, and electrochemical desalination systems, where auxiliary structures can be used in the vicinity of ion-selective surfaces. Especially, our fundamental electrokinetic study provides an effective means for designing the efficient electrochemical platforms utilizing micro/nanofluidics.

3.
Nano Lett ; 23(17): 8065-8072, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37581872

RESUMO

A nanoelectrokinetic phenomenon called ion concentration polarization (ICP) has been recently applied to microfluidic paper-based devices for the high fold preconcentration of low-abundant analytes. The inherent microstructural characteristics of cellulose papers can sufficiently stabilize the chaotic electroconvection of ICP, which is a significant annoyance for typical engineered microfluidic channels. However, a high electrical voltage to induce ICP in a paper-fluidic channel can increase unavoidable electrophoretic forces over drag forces so that the preconcentrated plug is rapidly receded with severe dispersion. In order to enhance the hydraulic drag force that helps the preconcentration of analytes, here we introduce a multilayered paper structure into paper-fluidic channel. We theoretically and experimentally demonstrate that a hierarchical capillary structure in a multilayered paper-fluidic channel can effectively increase the hydraulic drag force. For the practical utility in the field of diagnostics, the mechanism is verified by a simple example of the immunoassay using biotin-streptavidin complexation.

4.
Expert Rev Pharmacoecon Outcomes Res ; 23(5): 519-525, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36922505

RESUMO

OBJECTIVE: This study aims to analyze the effect of the copayment reduction system on accessibility to orphan drugs (ODs) in South Korea. METHODS: Data on approval and reimbursement for drugs designated as ODs for the last 10 years (2012-2021) in South Korea were extracted. Among them, with 136 approved products as of 31 December 2022, the reimbursement rates and lead time to reimbursement between drugs for rare diseases (DRDs) and nondrugs for rare diseases (non-DRDs) were analyzed. The pricing and reimbursement (P&R) pathways between drugs for only rare diseases (DORDs) and drugs for rare and cancerous diseases (DRCDs) were compared. RESULTS: The reimbursement rates for DRDs and non-DRDs were 54.8% and 33.3%, respectively, and the lead time to reimbursement for DRDs and non-DRDs were 16.1 months and 31.2 months, respectively. The P&R pathways for DORDs and DRCDs were pharmacoeconomic evaluation waivers (21.7% and 52.6%), weighted average price (52.2% and 13.2%), and risk-sharing agreement (30.4% and 81.6%). CONCLUSION: The copayment reduction system may act as a driver and also barrier for the reimbursement of ODs. To expand treatment accessibility to ODs, it is necessary to consistently grants benefits in all processes from OD designation to market access.


Assuntos
Produção de Droga sem Interesse Comercial , Doenças Raras , Humanos , Doenças Raras/tratamento farmacológico , Farmacoeconomia , Custos e Análise de Custo , República da Coreia
5.
Anal Chem ; 95(11): 5045-5052, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36893461

RESUMO

Cutting-edge nanoelectrokinetic technology in this work provides a breakthrough for the present clinical demands of molecular diagnosis to detect a trace amount of oncogenic mutation of DNA in a short time without an erroneous PCR procedure. In this work, we combined the sequence-specific labeling scheme of CRISPR/dCas9 and ion concentration polarization (ICP) mechanism to separately preconcentrate target DNA molecules for rapid detection. Using the mobility shift caused by dCas9's specific binding to the mutant, the mutated DNA and normal DNA were distinguished in the microchip. Based on this technique, we successfully demonstrated the dCas9-mediated 1-min detection of single base substitution (SBS) in EGFR DNA, a carcinogenesis indicator. Moreover, the presence/absence of target DNA was identified at a glance like a commercial pregnancy test kit (two lines for positive and one line for negative) by the distinct preconcentration mechanisms of ICP, even at the 0.1% concentration of the target mutant.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , DNA , Reação em Cadeia da Polimerase , DNA/genética , DNA/química , Mutação
6.
Sci Rep ; 13(1): 1811, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725965

RESUMO

In this study, we aimed to evaluate the benefits and losses of mammography with and without implant displacement (ID) and propose an appropriate imaging protocol for the screening of breasts with implants. We evaluated mammograms of 162 breasts in 96 patients including 71 breasts with biopsy-proven cancers. Mammography of each breast included standard MLO and ID MLO images. We reviewed the mammograms using clinical image quality criteria, which consist of parameters that evaluate the proper positioning of the breast and the image resolution. Standard MLO images showed significantly higher scores for proper positioning but showed significantly lower scores for image resolution than the ID MLO images. Moreover, standard MLO images showed significantly higher kVp, mAs, and compressed breast thickness than the ID MLO images. The organ dose was also higher in the standard MLO images than in the ID MLO images, but the difference was not statistically significant. In mammography with proven cancer, ID MLO images showed significantly higher degree of cancer visibility than standard MLO images. For screening mammography in patients with breast implants, ID MLO view alone is sufficient for MLO projection with reducing the patient's radiation dose without compromising the breast cancer detection capability, especially in dense breasts with subpectoral implants.


Assuntos
Implantes de Mama , Neoplasias da Mama , Feminino , Humanos , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Detecção Precoce de Câncer , Mamografia/métodos
7.
Front Bioeng Biotechnol ; 10: 964765, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046673

RESUMO

Polyene natural products including nystatin A1, amphotericin B, ECO-02301, and mediomycin belong to a large family of valuable antifungal polyketide compounds typically produced by soil actinomycetes. A previous study (Park et al., Front. Bioeng. Biotechnol., 2021, 9, 692340) isolated Streptomyces rubrisoli Inha501 with strong antifungal activity and analyzed a large-sized biosynthetic gene cluster (BGC) of a linear polyene compound named Inha-neotetrafibricin (I-NTF) using whole genome sequencing and bioinformatics. In the present study, an entire I-NTF BGC (∼167 kb) was isolated through construction and screening of Streptomyces BAC library. Overexpression of the cloned I-NTF BGC in the wild-type S. rubrisoli Inha501 and its heterologous expression in S. lividans led to 2.6-fold and 2.8-fold increase in I-NTF yields, respectively. The qRT-PCR confirmed that the transcription levels of I-NTF BGC were significantly increased in both homologous and heterologous hosts containing the BAC integration of I-NTF BGC. In addition, the I-NTF aglycone-producing strains were constructed by a target-specific deletion of glycosyltransferase gene present in I-NTF BGC. A comparison of the in vitro biological activities of I-NTF and I-NTF aglycone confirmed that the rhamnose sugar motif of I-NTF plays a critical role in both antifungal and antibacterial activities. These results suggest that the Streptomyces BAC cloning of a large-sized natural product BGC is a valuable approach for natural product titer improvement and biological activity screening of natural product in actinomycetes.

8.
Biomaterials ; 289: 121749, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36055174

RESUMO

We report that the electrostatic association between a cyanovinylene (CV)-based cationic dye (CV-N+) and anionic surfactants rapidly induced the formation of self-assembled aggregates of CV-N+ molecules in an aqueous solution, displaying a red-shifted (Δλ = 100 nm), broad excimer emission at 650 nm. The anionic-surfactant-mediated excimer-forming properties of CV-N+ were further exploited as a versatile platform for the design of simple fluorescent "light-up" sensing systems for the specific and efficient detection of enzymatic activity (i.e., phospholipase D) and small molecules (i.e., bisulfite ions), respectively, without the complicated functionalization of fluorophores with suitable recognition groups. In these systems, which can be ensembled using various substrates, the cationic CV-N+ dye interacts with an anionic surfactant, which is the product of an analyte-induced specific reaction, thus triggering the formation of emissive aggregates.


Assuntos
Fosfolipase D , Tensoativos , Cátions , Corantes Fluorescentes/química , Tensoativos/química , Água/química
9.
Data Brief ; 42: 108308, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35664653

RESUMO

The Seokbinggo is an ice cellar made of stone to store ice in the 1700s. The Seokbinggo, a traditional Korean stone architecture, can keep ice collected in winter until summer because the semi-subterranean structure utilizes the natural environment, and the insulation design is effective. However, these structures and scientific designs are not used as ice storage and are easily damaged by biological contamination. We present the environmental data of the inside and the metagenomic dataset of the soil samples from the Seokbinggo. Next-generation sequencing was carried out on an Illumina MiSeq platform. The raw sequence data used for analysis is available in NCBI under the Sequence Read Archive (SRA) with BioProject No. PRJNA727939 and SRA accession Nos. SRX10976613, SRX10976614, SRX10976615, SRX10976616, SRX10976617, SRX10976618, SRX10976619, SRX10976620. Environmental data, including data from Korea Meteorological Administration, is available in the Mendeley data repository with DOI: 10.17632/2r8gpg7pxn.1.

10.
J Microbiol Biotechnol ; 32(7): 911-917, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35719079

RESUMO

As valuable antibiotics, microbial natural products have been in use for decades in various fields. Among them are polyene compounds including nystatin, amphotericin, and nystatin-like Pseudonocardia polyenes (NPPs). Polyene macrolides are known to possess various biological effects, such as antifungal and antiviral activities. NPP A1, which is produced by Pseudonocardia autotrophica, contains a unique disaccharide moiety in the tetraene macrolide backbone. NPP B1, with a heptane structure and improved antifungal activity, was then developed via genetic manipulation of the NPP A1 biosynthetic gene cluster (BGC). Here, we generated a Streptomyces artificial chromosomal DNA library to isolate a large-sized NPP B1 BGC. The NPP B1 BGC was successfully isolated from P. autotrophica chromosome through the construction and screening of a bacterial artificial chromosome (BAC) library, even though the isolated 140-kb BAC clone (named pNPPB1s) lacked approximately 8 kb of the right-end portion of the NPP B1 BGC. The additional introduction of the pNPPB1s as well as co-expression of the 32-kb portion including the missing 8 kb led to a 7.3-fold increase in the production level of NPP B1 in P. autotrophica. The qRT-PCR confirmed that the transcription level of NPP B1 BGC was significantly increased in the P. autotrophica strain containing two copies of the NPP B1 BGCs. Interestingly, the NPP B1 exhibited a previously unidentified SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) inhibition activity in vitro. These results suggest that the Streptomyces BAC cloning of a large-sized, natural product BGC is a valuable approach for titer improvement and biological activity screening of natural products in actinomycetes.


Assuntos
Produtos Biológicos , COVID-19 , Streptomyces , Antibacterianos , Antifúngicos/química , Antifúngicos/farmacologia , Cromossomos Artificiais Bacterianos/genética , Clonagem Molecular , Humanos , Macrolídeos/química , Família Multigênica , Nistatina/química , Polienos/química , Polienos/farmacologia , RNA Viral , RNA Polimerase Dependente de RNA , SARS-CoV-2 , Streptomyces/genética
11.
Data Brief ; 39: 107515, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34765706

RESUMO

This article provides long-term environmental change data for wooden buildings; it also reflects environmental data provided by the Korea Meteorological Administration. In the case of field survey, data logger was installed on the left rear and right front sides of the buildings. Datasets on the Beopjusa temple were collected at 1 h intervals in each building. Korea Meteorological Administration data was collected from public database(data.kma.go.kr) and all data processed in excel. The data was collected at two sites from Daeungbojeon hall and Palsangjeon hall in the Beopjusa temple, Republic of Korea. Data sets at 1 h intervals are provided by collecting more than 170,000 pieces of data for each building. And monthly average dataset and difference value of time average data between inside and outside are provided. This data can be used as basic data for environmental change researcher or simulation researcher of wood condition.

12.
Plants (Basel) ; 10(9)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34579299

RESUMO

Different physiological and genetic studies show that the variations in the accumulation of pigment-stimulating metabolites result in color differences in soybean seed coats. The objective of this study was to analyze the nutrient contents and antioxidant potential in black, brown, and green seed-coated soybeans. Significant variations in protein (38.9-43.3%), oil (13.9-20.4%), total sugar (63.5-97.0 mg/g seed), total anthocyanin (3826.0-21,856.0 µg/g seed coat), total isoflavone (709.5-3394.3 µg/g seed), lutein (1.9-14.8 µg/g), total polyphenol (123.0-385.8 mg gallic acid/100 g seed), total flavonoid (22.1-208.5 mg catechin/100 g seed), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid (ABTS; 275.0-818.8 mg Trolox/100 g seed), and 2,2-diphenyl-1-picrylhydrazyl (DPPH; 96.3-579.7 mg Trolox/100 g seed) were found among the soybean genotypes. Ilpumgeomjeong2 contained the lowest protein but the highest oil and total sugar. The lowest oil-containing Wonheug had the highest protein content. Socheong2 was rich in all four variables of antioxidants. Anthocyanins were detected only in black soybeans but not in brown and green soybeans. The variation in isoflavone content was up to 5-fold among the soybean genotypes. This study could be a valuable resource for the selection and improvement of soybean because an understanding of the nutrient content and antioxidant potentials is useful to develop effective strategies for improving the economic traits; for example, the major emphasis of soybean breeding for fatty acids is to enhance the oleic and linoleic acid contents and to decrease linolenic acid content.

13.
Plants (Basel) ; 10(9)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34579348

RESUMO

Improving drought stress tolerance of soybean could be an effective way to minimize the yield reduction in the drought prevailing regions. Identification of drought tolerance-related quantitative trait loci (QTLs) is useful to facilitate the development of stress-tolerant varieties. This study aimed to identify the QTLs for drought tolerance in soybean using a recombinant inbred line (RIL) population developed from the cross between a drought-tolerant 'PI416937' and a susceptible 'Cheonsang' cultivar. Phenotyping was done with a weighted drought coefficient derived from the vegetative and reproductive traits. The genetic map was constructed using 2648 polymorphic SNP markers that distributed on 20 chromosomes with a mean genetic distance of 1.36 cM between markers. A total of 10 QTLs with 3.52-4.7 logarithm of odds value accounting for up to 12.9% phenotypic variance were identified on seven chromosomes. Five chromosomes-2, 7, 10, 14, and 20-contained one QTL each, and chromosomes 1 and 19 harbored two and three QTLs, respectively. The chromosomal locations of seven QTLs overlapped or located close to the related QTLs and/or potential candidate genes reported earlier. The QTLs and closely linked markers could be utilized in maker-assisted selection to accelerate the breeding for drought tolerance in soybean.

14.
Front Microbiol ; 12: 661053, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34054761

RESUMO

Glycogen is a polysaccharide that comprises α-1,4-linked glucose backbone and α-1,6-linked glucose polymers at the branching points. It is widely found in organisms ranging from bacteria to eukaryotes. The physiological role of glycogen is not confined to being an energy reservoir and carbon source but varies depending on organisms. Sulfolobus acidocaldarius, a thermoacidophilic archaeon, was observed to accumulate granular glycogen in the cell. However, the role of glycogen and genes that are responsible for glycogen metabolism in S. acidocaldarius has not been identified clearly. The objective of this study is to identify the gene cluster, which is composed of enzymes that are predicted to be involved in the glycogen metabolism, and confirm the role of each of these genes by constructing deletion mutants. This study also compares the glycogen content of mutant and wild type and elucidates the role of glycogen in this archaeon. The glycogen content of S. acidocaldarius MR31, which is used as a parent strain for constructing the deletion mutant in this study, was increased in the early and middle exponential growth phases and decreased during the late exponential and stationary growth phases. The pattern of the accumulated glycogen was independent to the type of supplemented sugar. In the comparison of the glycogen content between the gene deletion mutant and MR31, glycogen synthase (GlgA) and α-amylase (AmyA) were shown to be responsible for the synthesis of glycogen, whereas glycogen debranching enzyme (GlgX) and glucoamylase (Gaa) appeared to affect the degradation of glycogen. The expressions of glgC-gaa-glgX and amyA-glgA were detected by the promoter assay. This result suggests that the gradual decrease of glycogen content in the late exponential and stationary phases occurs due to the increase in the gene expression of glgC-gaa-glgX. When the death rate in nutrient limited condition was compared among the wild type strain, the glycogen deficient strain and the strain with increased glycogen content, the death rate of the glycogen deficient strain was found to be higher than any other strain, thereby suggesting that the glycogen in S. acidocaldarius supports cell maintenance in harsh conditions.

15.
J Ind Microbiol Biotechnol ; 48(3-4)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-33928363

RESUMO

Streptomyces species are soil-dwelling bacteria that produce vast numbers of pharmaceutically valuable secondary metabolites (SMs), such as antibiotics, immunosuppressants, antiviral, and anticancer drugs. On the other hand, the biosynthesis of most SMs remains very low due to tightly controlled regulatory networks. Both global and pathway-specific regulators are involved in the regulation of a specific SM biosynthesis in various Streptomyces species. Over the past few decades, many of these regulators have been identified and new ones are still being discovered. Among them, a global regulator of SM biosynthesis named WblA was identified in several Streptomyces species. The identification and understanding of the WblAs have greatly contributed to increasing the productivity of several Streptomyces SMs. This review summarizes the characteristics and applications on WblAs reported to date, which were found in various Streptomyces species and other actinobacteria.


Assuntos
Antibacterianos/biossíntese , Proteínas de Bactérias/metabolismo , Streptomyces/metabolismo , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Streptomyces/genética
16.
Data Brief ; 34: 106715, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33506081

RESUMO

Tomato belongs to the Solanaceae family of plants. It is a diploid plant with 12 chromosomes. Previous studies have reported that its genome size is 950 MB with 35,000 protein-coding genes. Micro-Tom Tomato is a miniature dwarf determinate tomato cultivar. It has a small-sized genome, a short lifecycle, and a short seed-setting under fluorescent light. These features are similar to those of Arabidopsis. Consequently, Micro-Tom Tomato is considered as a model cultivar of tomato (Solanum lycopersicum) suitable for research. We sequenced its transcriptomes to identify tissue-specific gene candidate profiles in different plant tissues (petals, sepals, pistils, and stamens) at developmental stages.

17.
Plants (Basel) ; 9(9)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911865

RESUMO

Pod shattering is an important reproductive process in many wild species. However, pod shattering at the maturing stage can result in severe yield loss. The objectives of this study were to discover quantitative trait loci (QTLs) for pod shattering using two recombinant inbred line (RIL) populations derived from an elite cultivar having pod shattering tolerance, namely "Daewonkong", and to predict novel candidate QTL/genes involved in pod shattering based on their allele patterns. We found several QTLs with more than 10% phenotypic variance explained (PVE) on seven different chromosomes and found a novel candidate QTL on chromosome 16 (qPS-DS16-1) from the allele patterns in the QTL region. Out of the 41 annotated genes in the QTL region, six were found to contain SNP (single-nucleotide polymorphism)/indel variations in the coding sequence of the parents compared to the soybean reference genome. Among the six potential candidate genes, Glyma.16g076600, one of the genes with known function, showed a highly differential expression levels between the tolerant and susceptible parents in the growth stages R3 to R6. Further, Glyma.16g076600 is a homolog of AT4G19230 in Arabidopsis, whose function is related to abscisic acid catabolism. The results provide useful information to understand the genetic mechanism of pod shattering and could be used for improving the efficiency of marker-assisted selection for developing varieties of soybeans tolerant to pod shattering.

18.
J Exerc Rehabil ; 16(1): 96-100, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32161740

RESUMO

The purpose of this study is to compare and analyze the difference of isokinetic muscle functions, anaerobic capabilities, pedaling power and maximum strength according to race-class of Korea racing cyclists. The participants in this study were 57 racing cyclist candidates who graduated from the Korea racing school. One year after graduation, we confirmed race-class of candidates and they were divided into three groups: the first-class racer group (FC, n=14), second-class racer group (SC, n=29), third-class racer group (TC, n=14). The isokinetic muscle strength of trunk and knee flexion/extension was measured using HUMAC NORM and basic physical strength such as squat and bench press was analyzed by Ariel device. As results of this study, % Fat (percentage of body fat) in FC group was the lowest compared to other groups. Isokinetic knee flexion strength was higher in FC group than SC and TC racer groups. Peak and average pedaling power as well as maximum muscle strength were significantly higher in FC group than in other groups. Our findings suggest new evidence that pedaling power and isokinetic muscle strength might be closely associated with race-class of Korea racing cyclists.

19.
Environ Sci Technol ; 54(1): 497-506, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31793772

RESUMO

Graphitic carbon nitride (CN) as a popular visible light photocatalyst needs to be better understood for environmental applications. The behaviors of CN as an environmental photocatalyst were systematically studied in comparison with a well-known TiO2 photocatalyst. The two photocatalysts exhibit different photocatalytic oxidation (PCO) behaviors and dependences on the experimental conditions (e.g., pH, Pt loading, and the kind of organic substrate and scavenger). The PCO of organic substrates was significantly enhanced by loading Pt on TiO2 under UV light (λ > 320 nm), whereas Pt-CN exhibited a lower PCO activity than bare CN under visible light (λ > 420 nm). While the presence of Pt enhances the charge separation in both TiO2/UV and CN/visible light systems (confirmed by transient IR absorption spectroscopic analysis), the opposite effects of Pt are ascribed to the different mechanisms of •OH generation in the two photocatalytic systems. The negative effect of Pt on CN is ascribed to the fact that Pt catalytically decomposes in situ-generated H2O2 (a main precursor of OH radical), which hinders •OH production. The production of OH radicals on CN is favored only at acidic pH but 1O2 generation is dominant in alkaline pH. The pH-dependent behaviors of reactive oxygen species generation on CN were confirmed by electron paramagnetic resonance spin trap measurements.


Assuntos
Peróxido de Hidrogênio , Titânio , Catálise , Luz
20.
J Exerc Rehabil ; 15(3): 401-406, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31316932

RESUMO

The purpose of this study was to investigate differences of maximum muscle strength and isokinetic knee and core muscle functions according to pedaling power of racing cyclist candidate. Subjects for this study were 200 racing cyclist candidates and divided into four groups: top 10% peak power group (TPP, n=20), low 10% peak power group (LPP, n=20), top 10% average power group (TAP, n=20), and low 10% average power group (LAP, n=20). The maximum muscle strength was consisted of grip strength, bench press and squat measured by Ariel device, and isokinetic knee and core muscle functions were analyzed by Humac Norm device. Significant differences between groups were determined with one-way repeated analysis of variance. As the result of this study, TPP and TAP groups showed significantly decreased body-fat mass and increased free fat mass when compared to LPP and LAP groups. The maximum strength of grip and squat was significantly higher in TPP and TAP than in other groups. Isokinetic knee extension and flexion strength was higher in TPP and TAP groups as well as isokinetic trunk extension and flexion functions were highest in TPP group. Thus, our findings suggest new evidence that muscle mass, maximal muscle strength, and isokinetic muscle functions might be important predictors of racing cyclist performance.

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