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1.
J Hazard Mater ; 475: 134939, 2024 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-38889466

RÉSUMÉ

Dense non-aqueous-phase liquids (DNAPLs) represent one of the most hazardous contaminants of groundwater, posing health risks to humans. Radon is generally used to trace DNAPLs; however, external factors, such as rainfall or stream water, can influence its efficacy. To overcome these limitations, this study pioneered the integration of radon and microbial community structures to explore DNAPL tracing and natural attenuation in the context of seasonal variations for human health risk assessments. The results showed that a radon tracer can estimate DNAPL saturation in the source zone, especially during the dry season when radon deficiency predominates. However, samples exhibited mixing effects during the wet season because of local precipitation. Moreover, bioremediation and low health risks were observed in the plume boundary zone, indicating that microbial dechlorination was a predominant factor determining these risks. The abnormal patterns of radon observed during the wet season can be elucidated by examining microbiological communities. Consequently, a combined approach employing radon and microbial analysis is advocated for the boundary zone, albeit with a less intensive management strategy, compared with that for the source zone. This novel coupling method offers a theoretical and practical foundation for managing DNAPL-contaminated groundwater.


Sujet(s)
Nappe phréatique , Radon , Saisons , Polluants radioactifs de l'eau , Nappe phréatique/microbiologie , Nappe phréatique/composition chimique , Radon/analyse , Appréciation des risques , Polluants radioactifs de l'eau/analyse , Microbiologie de l'eau , Humains , Dépollution biologique de l'environnement
2.
Food Microbiol ; 122: 104550, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38839218

RÉSUMÉ

Listeria monocytogenes presents significant risk to human health due to its high resistance and capacity to form toxin-producing biofilms that contaminate food. The objective of this study was to assess the inhibitory effect of citronella aldehyde (CIT) on L. monocytogenes and investigate the underlying mechanism of inhibition. The results indicated that the minimum inhibitory concentration (MIC) and Minimum sterilisation concentration (MBC) of CIT against L. monocytogenes was 2 µL/mL. At this concentration, CIT was able to effectively suppress biofilm formation and reduce metabolic activity. Crystalline violet staining and MTT reaction demonstrated that CIT was able to inhibit biofilm formation and reduce bacterial cell activity. Furthermore, the motility assessment assay revealed that CIT inhibited bacterial swarming and swimming. Scanning electron microscopy (SEM) and laser confocal microscopy (LSCM) observations revealed that CIT had a significant detrimental effect on L. monocytogenes cell structure and biofilm integrity. LSCM also observed that nucleic acids of L. monocytogenes were damaged in the CIT-treated group, along with an increase in bacterial extracellular nucleic acid leakage. The proteomic results also confirmed the ability of CIT to affect the expression of proteins related to processes including metabolism, DNA replication and repair, transcription and biofilm formation in L. monocytogenes. Consistent with the proteomics results are ATPase activity and ATP content of L. monocytogenes were significantly reduced following treatment with various concentrations of CIT. Notably, CIT showed good inhibitory activity against L. monocytogenes on cheese via fumigation at 4 °C.This study establishes a foundation for the potential application of CIT in food safety control.


Sujet(s)
Biofilms , Fromage , Listeria monocytogenes , Tests de sensibilité microbienne , Listeria monocytogenes/effets des médicaments et des substances chimiques , Listeria monocytogenes/croissance et développement , Listeria monocytogenes/physiologie , Fromage/microbiologie , Biofilms/effets des médicaments et des substances chimiques , Biofilms/croissance et développement , Antibactériens/pharmacologie , Conservation aliments/méthodes , Microbiologie alimentaire , Protéines bactériennes/métabolisme , Protéines bactériennes/génétique , Aldéhydes/pharmacologie , Extraits de plantes/pharmacologie , Monoterpènes acycliques/pharmacologie
3.
Nat Commun ; 15(1): 4306, 2024 May 21.
Article de Anglais | MEDLINE | ID: mdl-38773114

RÉSUMÉ

Heliorhodopsins (HeRs) have been hypothesized to have widespread functions. Recently, the functions for few HeRs have been revealed; however, the hypothetical functions remain largely unknown. Herein, we investigate light-modulation of heterodimeric multidrug resistance ATP-binding cassette transporters (OmrDE) mediated by Omithinimicrobium cerasi HeR. In this study, we classifiy genes flanking the HeR-encoding genes and identify highly conservative residues for protein-protein interactions. Our results reveal that the interaction between OcHeR and OmrDE shows positive cooperatively sequential binding through thermodynamic parameters. Moreover, light-induced OcHeR upregulates OmrDE drug transportation. Hence, the binding may be crucial to drug resistance in O. cerasi as it survives in a drug-containing habitat. Overall, we unveil a function of HeR as regulatory rhodopsin for multidrug resistance. Our findings suggest potential applications in optogenetic technology.


Sujet(s)
Transporteurs ABC , Lumière , Transporteurs ABC/métabolisme , Transporteurs ABC/génétique , Protéines bactériennes/métabolisme , Protéines bactériennes/génétique , Liaison aux protéines , Rhodopsines microbiennes/métabolisme , Rhodopsines microbiennes/génétique , Rhodopsines microbiennes/composition chimique , Optogénétique/méthodes
4.
AMB Express ; 14(1): 37, 2024 Apr 15.
Article de Anglais | MEDLINE | ID: mdl-38622373

RÉSUMÉ

This research aimed to investigate effects of different yeast culture (YC) levels on in vitro fermentation characteristics and bacterial and fungal community under high concentrate diet. A total of 5 groups were included in the experiment: control group without YC (CON), YC1 (0.5% YC proportion of substrate dry matter), YC2 (1%), YC3 (1.5%) and YC4 (2%). After 48 h of fermentation, the incubation fluids and residues were collected to analyze the ruminal fermentation parameters and bacterial and fungal community. Results showed that the ruminal fluid pH of YC2 and YC4 groups was higher (P < 0.05) than that of CON group. Compared with CON group, the microbial protein, propionate and butyrate concentrations and cumulative gas production at 48 h of YC2 group were significantly increased (P < 0.05), whereas an opposite trend of ammonia nitrogen and lactate was observed between two groups. Microbial analysis showed that the Chao1 and Shannon indexes of YC2 group were higher (P < 0.05) than those of CON group. Additionally, YC supplementation significantly decreased (P < 0.05) Succinivibrionaceae_UCG-001, Streptococcus bovis and Neosetophoma relative abundances. An opposite tendency of Aspergillus abundance was found between CON and YC treatments. Compared with CON group, the relative abundances of Prevotella, Succiniclasticum, Butyrivibrio and Megasphaera elsdenii were significantly increased (P < 0.05) in YC2 group, while Apiotrichum and unclassified Clostridiales relative abundances were decreased (P < 0.05). In conclusion, high concentrate substrate supplemented with appropriate YC (1%) can improve ruminal fermentation and regulate bacterial and fungal composition.

5.
J Formos Med Assoc ; 2024 Apr 22.
Article de Anglais | MEDLINE | ID: mdl-38653676

RÉSUMÉ

BACKGROUND: /Purpose: The Pediatric Eating Assessment Tool-10 (Pedi-EAT-10) is a caregiver-administrated subjective questionnaire for evaluating swallowing and feeding disorders among children. This study translated the Pedi-EAT-10 into Traditional Chinese and tested the translated version's reliability and validity. METHODS: Pedi-EAT-10 was translated into Traditional Chinese by experts and finalized after discussion and testing. A total of 168 participants, consisting of 32 children with dysphagia from a tertiary medical center and 136 healthy controls from its Children Care Center for Employees, were recruited. All participants were assessed by an otolaryngologist and speech-language pathologist. The reliability, validity, and efficacy of the translated Pedi-EAT-10 were analyzed to ensure it could be used to identify pediatric dysphagia and feeding problems. RESULTS: The Traditional Chinese version of the Pedi-EAT-10 had significant clinical discriminative validity between the dysphagia group and the control group (total score = 9.6 vs. 2.6, P < 0.001), acceptable test-retest reliability (intraclass correlation = 0.63), and excellent internal consistency (Cronbach's α = 0.91 for the entire cohort). The overall performance of the test for distinguishing children with dysphagia from normal controls was acceptable, and the area under the curve was 74.8% (sensitivity = 71.9%; specificity = 69.9%). The optimal cutoff score was ≥3 on the Youdex index. CONCLUSIONS: The Traditional Chinese version of the Pedi-EAT-10 has fair reliability and validity and can be quickly and easily completed by caregivers. The translated Ped-EAT-10 can be used as a first-line tool for assessing the need for further referral and instrumental examination.

6.
J Environ Manage ; 357: 120814, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38581896

RÉSUMÉ

Investigating the possible direction of a CO2-dissolved water plume migration near the potential CO2 leakage area is a significant task because it helps estimate the spatial and temporal monitoring scale to detect the signal of released CO2 from the storage. Accordingly, the Korea CO2 Storage Environmental Management (K-COSEM) research center tried to develop an intensive monitoring system and applied it to the artificial CO2 release test in the actual field. Monitoring data from the field tests depicted the horizontal movement of the CO2-dissolved water plume along the direction of the groundwater flow. However, it remains unclear how the CO2-dissolved water plume migrates vertically and how gas accumulation occurs near the capillary zone. The present study simulated the CO2 release test with a visual expression method utilizing a Hele-Shaw cell with hydraulic gradient conditions (i = 0, 0.1, and 0.01) and tried to estimate the significant influences on a diffusive-advective transport of the dissolved gas plume with the shallow aquifer condition. The visualization experiment results were intuitively verified to determine whether the theoretical principles of action related to plume flow applied in this context. The results suggest that a CO2-dissolved water plume is distributed by hydraulic gradients and density-driven CO2 convective flow. The plume shape, center, and area were analyzed using an image analyzer program; the results demonstrated that the plume characteristic evolved depending on the significant effects on the plume. When the plume was mainly affected by the hydraulic gradient, it rapidly moved from the injection point to the last boundary; in contrast, when it was influenced primarily by density-driven CO2 convective flow, it flowed diagonally downward in the shape of varied branches. The numerical model calculated the migration of the CO2-dissolved water plume affected by both factors. The laboratory experiment and numerical simulation results suggest that the migration of a CO2-dissolved water plume may be affected by the hydraulic gradient and density-driven CO2 convective transport. As such, these factors should be considered when designing and analyzing CO2 monitoring signals to detect CO2 leaks from shallow aquifer systems.


Sujet(s)
Nappe phréatique , Polluants chimiques de l'eau , Dioxyde de carbone , Eau , Simulation numérique , Polluants chimiques de l'eau/analyse
7.
Food Res Int ; 184: 114256, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38609234

RÉSUMÉ

Mycotoxins are important risk factors in beer. In this study, a liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed to determine 10 mycotoxins in beer within 6 min. The method is fast, efficient, and has a simple and quick sample preparation. Validation was conducted based on the performance standards specified in Commission Decision 657/2002/EC, and the results demonstrated excellent linearity (R2 > 0.99), repeatability (RSD < 5 %), quantification limits (0.005-20.246 µg/L), and recovery rates (77 %-118 %). The prevalence of the 10 mycotoxins in 96 beers purchased from the Chinese market was analyzed, and the exposure of the Chinese population to mycotoxins through beer consumption was assessed. Deoxynivalenol (DON) was detected in 93.75 % of the beers, and the incidence of fumonisins (FBs) and zearalenone (ZEN) exceeded 50 %. Beer intake contributed significantly to the exposure of aflatoxins (AFs) and DON, especially in males. Correlation analysis between mycotoxin content in beer, raw materials, and the brewing process revealed that the brewing process significantly affected the content of DON (P < 0.001), while auxiliary materials also had a significant impact on the content of FBs and DON (P < 0.001). This study holds great significance in producing higher quality and safer beer.


Sujet(s)
Aflatoxines , Mycotoxines , Mâle , Humains , Bière , Chromatographie en phase liquide , Spectrométrie de masse en tandem
8.
Plant Dis ; : PDIS10232226RE, 2024 Jun 13.
Article de Anglais | MEDLINE | ID: mdl-38319628

RÉSUMÉ

Based on our previous finding that polysaccharide peptide (PSP) has substantial antiviral activity, we cultured strawberry plants infected with strawberry mild yellow edge virus (SMYEV) or strawberry vein banding virus (SVBV) in Murashige and Skoog (MS) media supplemented with PSP to test its ability to eliminate these viruses. PSP not only improved the elimination of SMYEV and SVBV but also promoted the growth and rooting of strawberry plants in tissue culture. On the 45th day, the average height of the 'Ningyu' strawberry plants in the 1-mg/ml PSP treatment group was 1.91 cm, whereas that of the plants in the control group was 1.51 cm. After the same time point, the number of new leaves on the tissue culture media supplemented with 1 mg/ml and 500 µg/ml of PSP and without PSP were 4.92, 4.41, and 3.53, respectively. PSP also promoted strawberry rooting and significantly increased both the length and number of roots. In addition, after treatment with the 1-mg/ml PSP treatment in tissue culture for 45 days followed by meristem-shoot-tip culture, the elimination rates of SMYEV and SVBV in regenerated 'Ningyu' strawberry plants ranged from 60 to 100%. This study investigated the use of the antiviral agent PSP for virus elimination. PSP has a low production cost and thus has great application potential for virus elimination in crop plants.

9.
Clin Otolaryngol ; 49(1): 109-116, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37853961

RÉSUMÉ

OBJECTIVES: This study aims to identify characteristics in image-based computational fluid dynamics (CFD) in children with obstructive sleep apnea (OSA). DESIGN: Diagnostic study. SETTING: Hospital-based cohort. PARTICIPANTS: Children with symptoms suggestive of OSA were recruited and underwent polysomnography. MAIN OUTCOME MEASURES: Three-dimensional models of computational fluid dynamics were derived from cone-beam computed tomography. RESULTS: A total of 68 children participated in the study (44 boys; mean age: 7.8 years), including 34 participants having moderate-to-severe OSA (apnea-hypopnea index [AHI] greater than 5 events/h), and 34 age, gender, and body mass index percentile matched participants having primary snoring (AHI less than 1). Children with moderate-to-severe OSA had a significantly higher total airway pressure (166.3 vs. 39.1 Pa, p = .009), total airway resistance (9851 vs. 2060 Newton-metre, p = .004) and velocity at a minimal cross-sectional area (65.7 vs. 8.8 metre per second, p = .017) than those with primary snoring. The optimal cut-off points for moderate-to-severe OSA were 46.2 Pa in the total airway pressure (area under the curve [AUC] = 73.2%), 2373 Newton-metre in the total airway resistance (AUC = 72.5%) and 12.6 metres per second in the velocity at a minimal cross-sectional area (AUC = 70.5%). The conditional logistic regression model revealed that total airway pressure, total airway resistance and velocity at minimal cross-sectional area were significantly associated with an increased risk of moderate-to-severe OSA. CONCLUSIONS: This study demonstrates that CFD could be a useful tool for evaluating upper airway patency in children with OSA.


Sujet(s)
Larynx , Syndrome d'apnées obstructives du sommeil , Mâle , Enfant , Humains , Ronflement , Hydrodynamique , Tomodensitométrie à faisceau conique
10.
Sci Total Environ ; 912: 169422, 2024 Feb 20.
Article de Anglais | MEDLINE | ID: mdl-38135072

RÉSUMÉ

The increase in extreme heavy rain due to climate change is a critical factor in the fate of urban and agricultural pollutants in aquatic system. Nutrients, including NO3- and PO43-, are transported with surface and seepage waters into rivers, lakes and aquifers and can eventually lead to algal blooms. δ15N-NO3-, δ18O-NO3-, and δ11B combined with hydrogeochemical and microbial data for groundwater and surface water samples were interpreted to evaluate the fate of nutrients in a riverside area around weirs in Daegu, South Korea. Most of the ions showed similar concentrations in the groundwater samples before and after heavy rain while concentrations of major ions in surface water samples were diluted after heavy rain. However, Si, PO43-, Zn, Ce, La, Pb, Cu and a number of waterborne pathogens increased in surface water after heavy rain. The interpretation of δ11B, δ15N-NO3-, and δ18O-NO3- values using a Bayesian mixing model revealed that sewage and synthetic fertilizers were the main sources of contaminants in the groundwater and surface water samples. δ18O and SiO2 interpreted using the Bayesian mixing model indicated that the groundwater component in the surface water increased from 4.4 % to 17.9 % during the wet season. This is consistent with numerical simulation results indicating that the direct surface runoff and the groundwater baseflow contributions to the river system had also increased 6.4 times during the wet season. The increase in proteobacteria and decrease of actinobacteria in the surface water samples after heavy rain were also consistent with an increase of surface runoff and an increased groundwater component in the surface water. This study suggests that source apportionment based on chemical and multi-isotope data combined with numerical modeling approaches can be useful for identifying main hydrological and geochemical processes in riverside areas around weirs and can inform suggestions of effective methods for water quality management.


Sujet(s)
Polluants environnementaux , Nappe phréatique , Polluants chimiques de l'eau , Polluants chimiques de l'eau/analyse , Isotopes de l'azote/analyse , Surveillance de l'environnement/méthodes , Théorème de Bayes , Silice , Nitrates/analyse , Nappe phréatique/microbiologie , Pluie , Chine
11.
Laryngoscope ; 2023 Nov 01.
Article de Anglais | MEDLINE | ID: mdl-37909678

RÉSUMÉ

OBJECTIVE: Adenotonsillectomy is one of the most common surgical procedures performed on children. Caregivers are often concerned about voice change after the procedure, and such concerns remain unsettled. This meta-analysis analyzed voice change in children after adenotonsillectomy. DATA SOURCES: The PubMed, Medline, EMBASE, and Cochrane databases. REVIEW METHODS: The study protocol was registered on PROSPERO. Two authors independently searched for articles using keywords "adenoidectomy," "tonsillectomy, "voice," "nasalance,"and "speech." English articles specifying voice changes after adenotonsillectomy were pooled with standardized mean difference (SMD) using random-effects model. Evaluation methods were computerized acoustic voice analysis, aerodynamic analysis, nasometer, rhinomanometry, evaluations from a speech-language pathologist or otolaryngologist, and a caregiver assessment questionnaire. RESULTS: Twenty-three studies with 2154 children were analyzed (mean age: 8.0 y; 58% boys; mean sample size: 94 children). Due to insufficient data for other outcome variables, this meta-analysis only summarized changes in the computerized acoustic voice analysis 1 month and 3 months after surgery. The computerized acoustic analysis revealed significant changes in jitter (SMD = -0.36; 95% confidence interval [CI]: -0.60 to -0.11), shimmer (SMD = -0.34; 95% CI: -0.57 to -0.11), and soft phonation index (SMD = -0.36; 95% CI: -0.57 to -0.15) at 1 month after surgery. Parameters including fundamental frequency, jitter, noise-to-harmonics ratio, and shimmer were not significantly changed at 3 months after surgery. CONCLUSIONS: This meta-analysis observed small improvements in jitter, shimmer, and soft phonation index 1 month after surgery. No significant effects were observed in voice outcomes 3 months after surgery. Laryngoscope, 2023.

12.
J Formos Med Assoc ; 2023 Sep 15.
Article de Anglais | MEDLINE | ID: mdl-37718211

RÉSUMÉ

This review summarizes the current evidence in systematic reviews, meta-analysis and randomized controlled trials regarding adenotonsillectomy outcomes in pediatric obstructive sleep apnea (OSA). Adenotonsillectomy is effective in treating OSA in children without co-morbidities, despite postoperative residual OSA remained in roughly half of these children. For children with comorbidities such as Down syndrome, Prader-Willi syndrome, sickle cell disease, or cerebral palsy, adenotonsillectomy is less effective and associated with more postoperative complications than that in children without comorbidities. For other OSA-related outcomes, evidence from meta-analyses and randomized controlled trials confirm adenotonsillectomy results in improvement of subjective OSA-related outcomes (e.g. symptoms, behaviors, and quality of life), but the results in objective OSA-related outcomes (e.g. cardiometabolic parameters or neurocognitive functions) are inconsistent. Future studies should focus on randomized controlled trials comparing objective OSA-related outcomes and the long-term effects of adenotonsillectomy in children with OSA.

13.
Environ Int ; 178: 108098, 2023 08.
Article de Anglais | MEDLINE | ID: mdl-37467531

RÉSUMÉ

Groundwater is an important human resource. Daejeon in South Korea faces severe water quality issues, including radon, uranium, and fluoride pollution, all of which pose health risks to humans. With climate change, threats to potable water, such as heavy rain and typhoons, have become common. Therefore, examining the seasonal effects on groundwater quality and resultant health risks is important for understanding the mechanisms of different hydroclimatological conditions to enable the implementation of sustainable management plans in radon-contaminated groundwater areas. However, this issue has not yet been studied. To bridge this gap, in this study, major ions and microbial community structures were employed and groundwater quality index (GWQI) were calculated with hazard index based on limits set by the World Health Organization (WHO) to investigate the hydrochemical characterization and to assess pollution levels. The results showed that the rainy season had distinct hydrochemical characteristics with high correlations between radon and fluoride, and most groundwater samples collected after the typhoon had characteristics similar to those collected during the dry season, owing to the flow path. Furthermore, the microbial diversity and hazard quotient (HQ) values of fluoride revealed that pollution worsened during the dry season. All of the calculated effective dose values of radon exceeded the threshold limit set by the WHO, despite the low GWQI. Infants and children were particularly susceptible to radon-contaminated groundwater. The statistical results of self-organizing map (SOM) suggested that radon analysis was sufficient for public health intervention in the rainy season; however, in the dry season, combined analyses of radon, fluoride, and microbial diversity played important roles in health risk assessment. Our study presents a comprehensive understanding of radon-contaminated groundwater characteristics under seasonal effects and can serve as a reference for other similar zones to provide significant insights into the effective management of radon contamination.


Sujet(s)
Nappe phréatique , Radon , Polluants chimiques de l'eau , Nourrisson , Enfant , Humains , Saisons , Fluorures/analyse , Radon/analyse , Nappe phréatique/composition chimique , Qualité de l'eau , Appréciation des risques , Polluants chimiques de l'eau/analyse , Surveillance de l'environnement/méthodes
14.
J Hazard Mater ; 459: 132051, 2023 10 05.
Article de Anglais | MEDLINE | ID: mdl-37467612

RÉSUMÉ

The uranium inventory in the Boeun aquifer is situated near an artificial reservoir (40-70 m apart) intended to supply water to nearby cities. However, toxic radionuclides can enter the reservoir. To determine the U mobility in the system, we analyzed groundwater and fracture-filling materials (FFMs) for environmental tracers, including microbial signatures, redox-sensitive elements and isotopes. In the site, U mass flux ranged from only 9.59 × 10-7 µg/L/y to 1.70 × 10-4 µg/L/y. The δ18O-H2O and 14C signatures showed that groundwater originated mainly from upland recharges and was not influenced by oxic surface water. We observed U accumulations (∼157 mg/kg) in shallow FFMs and Fe enrichments (∼226798 mg/kg) and anomalies in the 230Th/238U activity ratio (AR), 230Th/234U AR, δ56Fe and δ57Fe isotopes, suggesting that low U mobility in shallow depths is associated with a Fe-rich environment. At shallow depths, anaerobic Fe-oxidizers, Gallionella was prevalent in the groundwater, while Acidovorax was abundant near the U ore deposit depth. The Fe-rich environment at shallow depths was formed by sulfide dissolution, as demonstrated by δ34S-SO4 and δ18O-SO4 distribution. Overall, the Fe-rich aquifer including abundant sulfide minerals immobilizes dissolved U through biotic and abiotic processes, without significant leaching into nearby reservoirs.


Sujet(s)
Nappe phréatique , Uranium , Polluants chimiques de l'eau , Isotopes , Minéraux , Oxydoréduction , Polluants chimiques de l'eau/analyse
15.
Sci Total Environ ; 888: 164129, 2023 Aug 25.
Article de Anglais | MEDLINE | ID: mdl-37187398

RÉSUMÉ

The occurrence of various N-related human activities increases the difficulty in distinguishing the major sources of NO3- contamination in groundwater, especially in areas with mixed land uses. In addition, the estimation of the timing and pathways of NO3- is necessary to better understand the processes of NO3- contamination in the subsurface aquifer system. This study applied environmental tracers, such as stable isotopes and age tracers (δ15N and δ18O of NO3-, δ11B, chlorofluorocarbons, and 3H), to elucidate the sources, timing, and pathways of NO3- contamination in the groundwaters of the Hanrim area, which has suffered from illegal disposal of livestock wastes since the 1980s, and also characterizes them based on mixed N-contaminant sources such as chemical fertilizers and sewage. The combined use of δ15N and δ11B overcame the limitation of using only NO3- isotopes for the identification of overlapping sources of N and successfully identified the major source of N as livestock wastes. The lumped parameter model (LPM) estimated the binary mixing of the young (age: 23-40 years, NO3-N: 2.55-15.10 mg/L) and old (age: >60 years, NO3-N: <3 mg/L) groundwaters, and explained their age mixing behaviors. The young groundwater was highly affected by livestock-derived N loading during 1987-1998, which coincides with the period of improper dumping of livestock wastes. Furthermore, the young groundwater with elevated NO3-N followed the historical NO3-N curves with younger ages (6 and 16 years) than those derived from the LPM, suggesting the possibility of faster inflows of livestock wastes through the permeable volcanic structures. This study demonstrated that a comprehensive understanding of NO3- contamination processes can be achieved using environmental tracer methods, which enables the efficient management of groundwater resources in areas with multiple N sources.

16.
Water Res ; 236: 119955, 2023 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-37087918

RÉSUMÉ

In the present study, a single-well push-pull (SWPP) test was conducted with multi-component tracers, including inert gas (SF6 and Kr) and uranine (conservative), to understand the volatile/semi-volatile component transport characteristics in the groundwater system. In an SWPP test, it is essential to obtain an initial breakthrough curve (BTC) of the inert gas concentration at the beginning of the pulling stage to analyze the hydraulic properties of the groundwater system. As a result of the SWPP test using a proposed method in this study, physicochemical parameters of the groundwater and BTC of gas tracers and uranine were acquired simultaneously and successfully. In addition, on-site measurements of uranine, pCO2, and water quality data, such as electrical conductivity (EC), temperature, pH, and dissolved oxygen, were undertaken. Modification of an existing pCO2 measuring system allowed the gas samples to be collected, transported, and analyzed for inert gas components within a few hours. As a result, reliable and interpretable data with a recovery ratio of 26%, 85%, and 95% for SF6, Kr, and uranine, respectively, were obtained. The differences in the recovery ratio were utilized to identify the environmental system, whether it contains gas inside the isolated system (closed) or not (open), and to understand plume behavior characteristics in the experimental zone. By applying a two-dimensional advection-dispersion model to the acquired tracer test data and comparing the observed and computed tracer concentrations, helpful information was obtained on the hydraulic and transport characteristics of the targeted zone. This method can be extended to the design of dissolved CO2 transport monitoring of an aquifer above a CCS site.


Sujet(s)
Nappe phréatique , Fluorescéine
17.
Plants (Basel) ; 12(4)2023 Feb 13.
Article de Anglais | MEDLINE | ID: mdl-36840176

RÉSUMÉ

Common root rot caused by Bipolaris sorokiniana infestation in wheat is one of the main reasons for yield reduction in wheat crops worldwide. The bacterium strain JK-25 used in the current investigation was isolated from wheat rhizosphere soil and was later identified as Bacillus halotolerans based on its morphological, physiological, biochemical, and molecular properties. The strain showed significant antagonism to B. sorokiniana, Fusarium oxysporum, Fusarium graminearum, and Rhizoctonia zeae. Inhibition of B. sorokiniana mycelial dry weight and spore germination rate by JK-25 fermentation supernatant reached 60% and 88%, respectively. The crude extract of JK-25 was found, by Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), to contain the surfactin that exerted an inhibitory effect on B. sorokiniana. The disruption of mycelial cell membranes was observed under laser scanning confocal microscope (LSCM) after treatment of B. sorokiniana mycelium with the crude extract. The antioxidant enzyme activity of B. sorokiniana was significantly reduced and the oxidation product malondialdehyde (MDA) content increased after treatment with the crude extract. The incidence of root rot was significantly reduced in pot experiments with the addition of JK-25 culture fermentation supernatant, which had a significant biological control effect of 72.06%. Its ability to produce siderophores may help to promote wheat growth and the production of proteases and pectinases may also be part of the strain's role in suppressing pathogens. These results demonstrate the excellent antagonistic effect of JK-25 against B. sorokiniana and suggest that this strain has great potential as a resource for biological control of wheat root rot strains.

18.
J Hazard Mater ; 446: 130703, 2023 03 15.
Article de Anglais | MEDLINE | ID: mdl-36587594

RÉSUMÉ

The excessive input of nutrients into groundwater can accelerate eutrophication in associated surface water systems. This study combined hydrogeochemistry, multi isotope tracers, and microbiological data to estimate nutrient sources and the effects of groundwater-surface water interactions on the spatiotemporal variation of nutrients in groundwater connected to a large weir-regulated river in South Korea. δ11B and δ15N-NO3- values, in combination with a Bayesian mixing model, revealed that manure and sewage contributed 40 % and 25 % respectively to groundwater nitrate, and 42 % and 27 % to nitrate in surface water during the wet season. In the dry season, the source apportionment was similar for groundwater while the sewage contribution increased to 52 % of nitrate in river water. River water displayed a high correlation between NO3- concentration and cyanobacteria (Microcystis and Prochlorococcus) in the wet season. The mixing model using multiple isotopes indicated that manure-derived nutrients delivered with increased contributions of groundwater to the river during the wet season governed the occurrence of cyanobacterial blooms in the river. We postulate that the integrated approach using multi-isotopic and microbiological data is highly effective for evaluating nutrient sources and for delineating hydrological interactions between groundwater and surface water, as well as for investigating surface water quality including eutrophication in riverine and other surface water systems.


Sujet(s)
Nappe phréatique , Polluants chimiques de l'eau , Isotopes de l'azote/analyse , Rivières , Nitrates/analyse , Eaux d'égout , Fumier , Théorème de Bayes , Surveillance de l'environnement , Polluants chimiques de l'eau/analyse , Chine
19.
Clin Otolaryngol ; 48(2): 321-329, 2023 03.
Article de Anglais | MEDLINE | ID: mdl-36097380

RÉSUMÉ

OBJECTIVE: This study aimed to elucidate the revision rate, time to revision, and factors associated with revision of endoscopic sinus surgery (ESS) in Taiwan. DESIGN: Retrospective study. SETTING: Population-based analysis. PARTICIPANT: We identified all in-hospital patients, aged >20 years, who underwent ESS between 2000 and 2008 from the Taiwan National Health Insurance Research Database, and followed up with them until 2018. MAIN OUTCOME MEASURES: Factors associated with revision surgery were analyzed using multivariable Cox proportional hazard model. RESULTS: Overall, 66 592 patients were identified (mean age, 46.3 years; 62% males). The revision rate was 14.5% (9644/66 592) and time to revision surgery was 5.9 years. Multivariable Cox proportional hazard model showed that young age, male gender (hazard ratio [HR] = 1.18; 95% confidence interval [CI], 1.13-1.23), having nasal polyposis (HR = 1.17; 95% CI, 1.12-1.22), having allergic rhinitis (HR = 1.08; 95% CI, 1.04-1.13), having asthma (HR = 1.26; 95% CI, 1.14-1.39), and surgical time of >4 h (HR = 1.11; 95% CI, 1.06-1.16) were associated with increased risk of revision surgery. Concurrent septal surgery (HR = 0.81; 95% CI, 0.76-0.87), turbinate surgery (HR = 0.91; 95% CI, 0.85-0.97), or septal and turbinate surgery (HR = 0.68; 95% CI, 0.64-0.73) were associated with decreased risks of revision surgery. CONCLUSION: In Taiwan, risk factors for revision ESS are young age, male gender, having nasal polyposis, having allergic rhinitis, having asthma, and long surgical times. Concurrent septal or turbinate surgery decreases the risk of revision.


Sujet(s)
Asthme , Polypes du nez , Rhinite allergique , Rhinite , Sinusite , Humains , Adulte , Mâle , Adulte d'âge moyen , Femelle , Sinusite/complications , Études rétrospectives , Taïwan/épidémiologie , Maladie chronique , Asthme/complications , Rhinite allergique/complications , Endoscopie , Réintervention , Polypes du nez/épidémiologie , Polypes du nez/chirurgie , Polypes du nez/complications , Rhinite/complications
20.
Animals (Basel) ; 14(1)2023 Dec 21.
Article de Anglais | MEDLINE | ID: mdl-38200771

RÉSUMÉ

It has been confirmed that improving the energy level of the diet contributed to the greater reproductive performance and birth weight of calves in periparturient dairy cows. To investigate the effect of glucose on nutrient transport during fetal development, the bovine placental trophoblast cells (BPTCs) were cultured in media with different glucose concentrations (1, 2, 4, 8, or 16 mg/mL). Subsequently, the BPTCs were cultured in media with 1, 8 mg/mL glucose and 8 mg/mL glucose plus 100 nmol/L rapamycin (the inhibitor of mTOR pathway). Compared with the 1 mg/mL glucose, the addition of 8 mg/mL glucose stimulated cell proliferation, upregulated the mRNA abundance of the glucose transporter GLUT1 and GLUT4, and increased the activity of glucose metabolism-related enzyme glucose-6-phosphate dehydrogenease (G6PD), lactate dehydrogenase (LDHA) and phosphoglycerate kinase 1 (PGK1), as well as adenosine-triphosphate (ATP) content (p < 0.05).Furthermore, compared with the treatment of 1 mg/mL glucose, adding 8 mg/mL of glucose-upregulated gene expression in the mTOR signaling pathway, including phosphatidylinositol3-kinase (PI3K), protein kinase B (Akt), mammalian target of rapamycin (mTOR) and 70 kDa ribosomal protein S6 kinase 2 (P70S6K) (p < 0.05).The supplementation of rapamycin downregulated the gene and protein expression of the mTOR signaling pathway, including mTOR, P70S6K, EIF4E-binding protein 1 (4EBP1), hypoxia-inducible factor 1-alpha (HIF-1α) and gene expression of glucose transporter upregulated by 8 mg/mL glucose (p < 0.05). Thus, these results indicated that the addition of 8 mg/mL glucose regulated the glucose transport and metabolism in BPTCs through the mTOR signaling pathway, thereby promoting the supply of nutrients to fetus.

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