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1.
J Environ Sci (China) ; 148: 625-636, 2025 Feb.
Article de Anglais | MEDLINE | ID: mdl-39095195

RÉSUMÉ

Woodchip bioreactors are an eco-friendly technology for removing nitrogen (N) pollution. However, there needs to be more clarity regarding the dissolved organic matter (DOM) characteristics and bacterial community succession mechanisms and their association with the N removal performance of bioreactors. The laboratory woodchip bioreactors were continuously operated for 360 days under three influent N level treatments, and the results showed that the average removal rate of TN was 45.80 g N/(m3·day) when the influent N level was 100 mg N/L, which was better than 10 mg N/L and 50 mg N/L. Dynamic succession of bacterial communities in response to influent N levels and DOM characteristics was an important driver of TN removal rates. Medium to high N levels enriched a copiotroph bacterial module (Module 1) detected by network analysis, including Phenylobacterium, Xanthobacteraceae, Burkholderiaceae, Pseudomonas, and Magnetospirillaceae, carrying N-cycle related genes for denitrification and ammonia assimilation by the rapid consumption of DOM. Such a process can increase carbon limitation to stimulate local organic carbon decomposition to enrich oligotrophs with fewer N-cycle potentials (Module 2). Together, this study reveals that the compositional change of DOM and bacterial community succession are closely related to N removal performance, providing an ecological basis for developing techniques for N-rich effluent treatment.


Sujet(s)
Bactéries , Bioréacteurs , Azote , Élimination des déchets liquides , Bioréacteurs/microbiologie , Azote/analyse , Bactéries/métabolisme , Élimination des déchets liquides/méthodes , Microbiote
2.
J Palliat Med ; 2024 Aug 07.
Article de Anglais | MEDLINE | ID: mdl-39112021

RÉSUMÉ

Background: Despite physical and emotional distress in patients with gynecologic malignancies, palliative care (PC) is underutilized. Objectives: We characterize referral practices, symptom burden and functional status at the time of initial PC encounter for patients with gynecologic cancer. Design: Data were extracted from the standardized Quality Data Collection Tool for Palliative Care (QDACT-PC). We describe symptom burden and performance status. Results: At initial specialty PC encounter, patients with gynecologic cancers reported a mean of 3.3 moderate/severe symptoms. Outpatients experienced the most moderate/severe symptoms (mean 3.9) versus inpatient (mean 2.1) or home (mean 1.5). A total of 72.7% of patients had significantly impaired functional status (palliative performance scale [PPS] <70) at initial encounter. Inpatients had a more impaired functional status (mean PPS 48.8) than outpatients (mean PPS 67.0). Conclusions: The symptom burden for gynecologic cancer patients at initial PC encounter is high. Despite better functional status, patients referred in the outpatient setting had the highest symptom burden.

3.
ISA Trans ; 2024 Jul 27.
Article de Anglais | MEDLINE | ID: mdl-39112128

RÉSUMÉ

This study proposes a direct synthesis-based two-degree-of-freedom (2-DOF) controller for various types of integrating processes with time delays. This 2-DOF controller includes a proportional-integral-derivative (PID) controller to enhance load disturbance rejection performance and a set-point filter to improve servo response performance. The main PID controller parameters are expressed as process model parameters and a single adjustment variable, while the set-point filter is composed of PID controller parameters with weighted factors. The adjustment variable is tuned to achieve an optimal balance between response performance and robustness, based on the maximum magnitude of the sensitivity function (Ms). Controller parameters for various Ms values and guidelines for setting these parameters are provided in a consistent formulaic form using a curve-fitting method. These parameter-setting formulas facilitate the accurate implementation of PID controllers with specified Ms values and allow the controller design to be extended to processes with larger dimensionless time delays for a given Ms value. Although a 2-DOF controller was proposed, the adjustment variable for setting the parameters of the main PID controller and the set-point filter was solely the desired time constant. The proposed method was applied to various integrating processes with time delays, and its performance was compared with existing methods reported in the literature, based on performance indices such as settling time, overshoot, integral of absolute error, total variation in input usage, and global performance index. Simulations were conducted using six examples of various integrating processes with time delays to verify the effectiveness and applicability of the proposed controller.

4.
Sci Rep ; 14(1): 17124, 2024 08 07.
Article de Anglais | MEDLINE | ID: mdl-39112552

RÉSUMÉ

Gut bacterial communities have a profound influence on the health of humans and animals. Early-life gut microbial community structure influences the development of immunological competence and susceptibility to disease. For the Thoroughbred racehorse, the significance of early-life microbial colonisation events on subsequent health and athletic performance is unknown. Here we present data from a three-year cohort study of horses bred for racing designed to explore interactions between early-life gut bacterial community structure, health events in later life and athletic performance on the racetrack. Our data show that gut bacterial community structure in the first months of life predicts the risk of specific diseases and athletic performance up to three years old. Foals with lower faecal bacterial diversity at one month old had a significantly increased risk of respiratory disease in later life which was also associated with higher relative abundance of faecal Pseudomonadaceae. Surprisingly, athletic performance up to three years old, measured by three different metrics, was positively associated with higher faecal bacterial diversity at one month old and with the relative abundance of specific bacterial families. We also present data on the impact of antibiotic exposure of foals during the first month of life. This resulted in significantly lower faecal bacterial diversity at 28 days old, a significantly increased risk of respiratory disease in later life and a significant reduction in average prize money earnings, a proxy for athletic performance. Our study reveals associations between early-life bacterial community profiles and health events in later life and it provides evidence of the detrimental impact of antimicrobial treatment in the first month of life on health and performance outcomes in later life. For the first time, this study demonstrates a relationship between early-life gut bacterial communities and subsequent athletic performance that has implications for athletes of all species including humans.


Sujet(s)
Fèces , Microbiome gastro-intestinal , Equus caballus , Animaux , Fèces/microbiologie , Maladies des chevaux/microbiologie , Performance sportive , Bactéries/classification , Bactéries/génétique , Mâle , Femelle
5.
BMC Vet Res ; 20(1): 350, 2024 Aug 07.
Article de Anglais | MEDLINE | ID: mdl-39113022

RÉSUMÉ

BACKGROUND: The current study was conducted to assess the impact of different LED light colors on welfare indicators in Muscovy ducks. These welfare parameters encompassed growth performance, specific behaviors, tonic immobility (TI), feather score, haematological, and serum biochemical parameters. Eighty-four healthy unsexed Muscovy ducklings aged two weeks were randomly assigned to four groups (3replicates/group; each replicate contains 7 birds) based on different LED light colors. The first group was raised under white light, the second under red light, the third under blue light, and the fourth under yellow light. To assess the impact of various LED light colors on welfare, growth performance indicators (body weight, body weight gain, feed intake, and feed conversion ratio) were measured. Behavioral patterns including feeding, drinking, standing, walking, sitting, feather pecking, and other activities were recorded. Tonic immobility test (TI) and feather condition scoring were conducted at 3, 6, and 10 weeks of age. At the end of the study blood samples were collected for hematological and serum biochemical analyses. RESULTS: The results revealed that using blue, yellow, and red colors had no adverse effect on the final body weight of the ducks (P > 0.05). Unlike to red light, blue light significantly reduced feather pecking, TI time and cortisol concentrations and improved the feather condition score (P ≤ 0.05). CONCLUSIONS: The current findings suggest that the application of blue light effectively improves welfare indices and has no detrimental impact on the growth performance of Muscovy ducks thereby positively contributing to their welfare.


Sujet(s)
Bien-être animal , Comportement animal , Couleur , Canards , Animaux , Canards/physiologie , Canards/sang , Lumière , Plumes , Réaction d'immobilité tonique/physiologie , Poids , Mâle , Élevage/méthodes , Femelle
6.
BMC Health Serv Res ; 24(1): 901, 2024 Aug 07.
Article de Anglais | MEDLINE | ID: mdl-39113065

RÉSUMÉ

BACKGROUND: The COVID-19 pandemic wreaked havoc on long-term care facilities (LTCFs). Some LTCFs performed better than others at slowing COVID-19 transmission. Emerging literature has mostly described infection prevention and control strategies implemented by LTCFs during the pandemic. However, there is a need for a comprehensive review of factors that influenced the performance of LTCFs in containing COVID-19 spread to inform public health policy. OBJECTIVE: To build on the existing literature, we conducted a scoping review of factors that influenced LTCF performance during the COVID-19 pandemic using a multidimensional conceptual framework of performance. METHODS: We followed the Joanna Briggs Institute's methodology for scoping reviews. We queried CINAHL, MEDLINE (Ovid), CAIRN, Science Direct, Scopus, and Web of Science for peer-reviewed literature in English or French published between January 1st, 2020 and December 31st, 2021. Retrieved records were screened for context (COVID-19 pandemic), population (LTCFs), interest (internal and external factors that influenced LTCF performance), and outcomes (dimensions of performance: equity, accessibility, reactivity, safety, continuity, efficacy, viability, efficiency). Descriptive characteristics of included articles were summarized. Dimensions of performance as well as internal (e.g., facility characteristics) and external (e.g., visitors) factors identified to have influenced LTCF performance were presented. RESULTS: We retained 140 articles of which 68% were classified as research articles, 47% originated in North America, and most covered a period between March and July 2020. The most frequent dimensions of performance were "efficacy" (75.7%) and "safety" (75.7%). The most common internal factors were "organizational context" (72.9%) and "human resources" (62.1%), and the most common external factors were "visitors" (27.1%) and "public health guidelines" (25.7%). CONCLUSIONS: Our review contributes to a global interest in understanding the impact of the COVID-19 pandemic on vulnerable populations residing and working in LTCFs. Though a myriad of factors were reported, a lack of randomized controlled trials makes it impossible to establish causality between the identified factors and LTCF performance. The use of a multidimensional framework can be recommended to evaluate healthcare system performance not merely in terms of efficacy and safety, but alongside other critical dimensions such as efficiency and equity. TRIAL REGISTRATION: Research Registry ID: researchregistry7026.


Sujet(s)
COVID-19 , Soins de longue durée , COVID-19/prévention et contrôle , COVID-19/épidémiologie , Humains , SARS-CoV-2 , Pandémies/prévention et contrôle , Prévention des infections/méthodes , Prévention des infections/organisation et administration
7.
J Appl Behav Anal ; 2024 Aug 07.
Article de Anglais | MEDLINE | ID: mdl-39113246

RÉSUMÉ

Behavioral skills training (BST) has been used to improve football players' performance in one prior study, but limited data were collected on how the skill generalized from the training environment to the natural environment. The purpose of this study was to further evaluate the effects of BST in enhancing football players' performance while also evaluating the generalization of a skill taught in a training environment (i.e., practice) to the natural environment (i.e., game-simulated scrimmage). This study included five high school offensive line football players and recorded their run-blocking skills in the training context and a game context in baseline and following BST. The results showed that BST improved performance in the training environment, with run-blocking skills slightly generalizing from the training environment to game-simulated scrimmages. When BST was conducted in the natural environment, it further improved the participants' run-blocking skills.

8.
Health Informatics J ; 30(3): 14604582241272771, 2024.
Article de Anglais | MEDLINE | ID: mdl-39115432

RÉSUMÉ

Purpose: To identify the main variables affecting the academic adaptability of hospital nursing interns and key areas for improvement in preparing for future unpredictable epidemics. Methods: The importance of academic resilience-related variables for all nursing interns was analyzed using the random forest method, and key variables were further identified. An importance-performance analysis was used to identify the key improvement gaps regarding the academic resilience of nursing interns in the case hospital. Results: The random forest showed that five items related to cooperation, motivation, confidence, communication, and difficulty with coping were the main variables impacting the academic resilience of nursing interns. Moreover, the importance-performance analysis revealed that three items regarding options examination, communication, and confidence were the key improvement areas for participating nursing interns in the case hospital. Conclusions: For the prevention and control of future unpredictable pandemics, hospital nursing departments can strengthen the link between interns, nurses, and physicians and promote their cooperation and communication during clinical practice. At the same time, an application can be created considering the results of this study and combined with machine learning methods for more in-depth research. These will improve the academic resilience of nursing interns during the routine management of pandemics within hospitals.


Sujet(s)
Résilience psychologique , Humains , Internat et résidence/méthodes , Mâle , Femelle , Élève infirmier/psychologie , Élève infirmier/statistiques et données numériques
9.
Se Pu ; 42(8): 731-739, 2024 Aug.
Article de Chinois | MEDLINE | ID: mdl-39086241

RÉSUMÉ

Edible plant oils are a key component of the daily human diet, and the quality and safety of plant oils are related to human health. Perfluorinated and polyfluoroalkyl substances (PFASs) are pollutants that can contaminate plant oil through the processing of raw materials or exposure to materials containing these substances. Thus, establishing a sensitive and accurate analytical method for the determination of PFASs is critical for ensuring the safety of plant oils. In this study, a method based on acetonitrile extraction and solid phase extraction purification combined with ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC-MS/MS) was developed for the simultaneous determination of 21 PFASs, including perfluorocarboxylic acids, perfluoroalkyl sulfonic acids, and fluorotelomer sulfonic acids, in edible plant oils. The chromatographic conditions and MS parameters were optimized, and the influences of the extraction solvents and purification method were systematically studied. Plant oil samples were directly extracted with acetonitrile and purified using a weak anion-exchange (WAX) column. The 21 target PFASs were separated on a reversed-phase C18 chromatographic column and detected using a triple quadrupole mass spectrometer with an electrospray ionization source. The mass spectrometer was operated in negative-ion mode. The target compounds were analyzed in multiple reaction monitoring (MRM) mode and quantified using an internal standard method. The results demonstrated that the severe interference observed during the detection of PFASs in the co-extracted substances was completely eliminated after the extraction mixture was purified using a WAX column. The 21 target PFASs showed good linearity in their corresponding ranges, with correlation coefficients greater than 0.995. The limits of detection (LODs) and limits of quantification (LOQs) of the method were in the range of 0.004-0.015 and 0.015-0.050 µg/kg, respectively. The recoveries ranged from 95.6% to 115.8%, with relative standard deviations (RSDs) in the range of 0.3%-10.9% (n=9). The established method is characterized by simple sample pretreatment, good sensitivity, high immunity to interferences, and good stability, rendering it suitable for the rapid analysis and accurate determination of typical PFASs in edible plant oils.


Sujet(s)
Fluorocarbones , Contamination des aliments , Huiles végétales , Spectrométrie de masse en tandem , Chromatographie en phase liquide à haute performance/méthodes , Fluorocarbones/analyse , Spectrométrie de masse en tandem/méthodes , Contamination des aliments/analyse , Huiles végétales/composition chimique , Huiles végétales/analyse
10.
Se Pu ; 42(8): 740-748, 2024 Aug.
Article de Chinois | MEDLINE | ID: mdl-39086242

RÉSUMÉ

Perfluorinated and polyfluoroalkyl substances (PFASs) are compounds characterized by at least one perfluorinated carbon atom in an alkyl chain linked to side-chain groups. Owing to their unique chemical properties, these compounds are widely used in industrial production and daily life. However, owing to anthropogenic activities, sewage discharge, surface runoff, and atmospheric deposition, PFASs have gradually infiltrated the environment and aquatic resources. With their gradual accumulation in environmental waters, PFASs have been detected in fishes and several fish-feeding species, suggesting that they are bioconcentrated and even amplified in aquatic organisms. PFASs exhibit high intestinal absorption efficiencies, and they bioaccumulate at higher trophic levels in the food chain. They can be bioconcentrated in the human body via food (e. g., fish) and thus threaten human health. Therefore, establishing an efficient analytical technique for use in analyzing PFASs in typical fish samples and providing technical support for the safety regulation and risk assessment of fish products is necessary. In this study, by combining solvent extraction and magnetic dispersion-solid phase extraction (d-SPE), an improved QuEChERS method with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was developed for the determination of 13 PFASs in fish samples. Fe3O4-TiO2 can be used as an ideal adsorbent in the removal of sample matrix interference and a separation medium for the rapid encapsulation of other solids to be isolated from the solution. Based on the matrix characteristics of the fish products and structural properties of the target PFASs, Fe3O4-TiO2 and N-propyl ethylenediamine (PSA) were employed as adsorbents in dispersive purification. The internal standard method was used in the quantitative analyses of the PFASs. To optimize the sample pretreatment conditions of analyzing PFASs, the selection of the extraction solvent and amounts of Fe3O4-TiO2 and PSA were optimized. Several PFASs contain acidic groups that are non-dissociated in acidic environments, thus favoring their entry into the organic phase. In addition, acidified acetonitrile can denature and precipitate the proteins within the sample matrix, facilitating their removal. Finally, 2% formic acid acetonitrile was used as the extraction solvent, and 20 mg Fe3O4-TiO2, 20 mg PSA and 120 mg anhydrous MgSO4 were used as purification adsorbents. Under the optimized conditions, the developed method exhibited an excellent linearity (R≥0.9973) in the range of 0.01-50 µg/L, and the limits of detection (LODs) and quantification (LOQs) ranged from 0.001-0.023 and 0.003-0.078 µg/L, respectively. The recoveries of the 13 PFASs at low, medium, and high spiked levels (0.5, 10, and 100 µg/kg) were 78.1%-118%, with the intra- and inter-day precisions of 0.2%-11.1% and 0.8%-8.7%, respectively. This method was applied in analyzing real samples, and PFASs including perfluorooctanesulfonic acid, perfluorooctanoic acid, perfluoroundecanoic acid, perfluorododecanoic acid, and perfluorotridecanoic acid, were detected in all 11 samples evaluated. This method is simple, sensitive, and suitable for use in analyzing PFASs in fish samples.


Sujet(s)
Poissons , Fluorocarbones , Contamination des aliments , Spectrométrie de masse en tandem , Spectrométrie de masse en tandem/méthodes , Fluorocarbones/analyse , Animaux , Chromatographie en phase liquide à haute performance , Contamination des aliments/analyse , Caprylates/analyse , Acides alcanesulfoniques/analyse
11.
Se Pu ; 42(8): 758-765, 2024 Aug.
Article de Chinois | MEDLINE | ID: mdl-39086244

RÉSUMÉ

Milk is an important consumer product with high nutritional value. The presence of veterinary drug residues in milk owing to the indiscriminate use of veterinary drugs may affect consumer health. In the mass spectrometric analysis of trace compounds, chromatographic co-eluting components easily interfere with the mass spectral signals obtained, affecting the accuracy of qualitative and quantitative analyses. Matrix purification is a promising method to reduce the matrix effect. Chitosan is a natural biopolymer with numerous active functional groups such as amino, acetyl, and hydroxyl groups; these groups can adsorb lipids through hydrophobic and electrostatic interactions. Chitosan also has the advantages of low production cost, stable chemical properties, and convenient modification. Novel chitosan-based materials are promising candidates for lipid purification. In this study, a chitosan membrane was modified with trimethoxyoctadecylsilane (C18-CSM). C18-CSM was prepared through one-step hydrolysis and used as a dispersive solid phase extraction (DSPE) adsorbent to purify the matrix during milk pretreatment. We combined C18-CSM with ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap mass spectrometry (UHPLC-Q/Exactive Orbitrap MS) to develop an effective method for the extraction and determination of ofloxacin, enrofloxacin, ciprofloxacin, diazepam, and metronidazole in milk. C18-CSM was characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, and water contact angle testing. The results indicated that the material has a rough surface and uniformly dense cross-section. The water contact angle of C18-CSM was 104°, indicating its good hydrophobicity. The pretreatment conditions (extraction solvent, dosage of NaCl, extraction frequency, and dosage of C18-CSM) that influenced the recoveries of the five veterinary drugs were investigated in detail. The optimal conditions were established as follows: 5% formic acid in acetonitrile, 1 g NaCl, extraction 1 time, 20 mg C18-CSM. Separation was performed on a Hypersil GOLD VANQUISH column (100 mm×2.1 mm, 1.9 µm). The mobile phase consisted of 0.1% formic acid aqueous solution and 0.1% formic acid in acetonitrile, and was flowed at a rate of 0.3 mL/min. The sample injection volume was 1 µL, and the column temperature was maintained at 25 ℃. Mass spectrometric analysis was performed in positive electrospray ionization mode. To verify the necessity of the purification material, the matrix effect was investigated using the matrix-matched standard curve method. The use of C18-CSM reduced the matrix effects of the five necessity drugs from the range of -22%-8.8% to the range of -13%-3.6%, indicating that C18-CSM is a highly efficient DSPE material. Under optimal conditions, the developed method showed good linearities within the range of 0.5-100 µg/L, with correlation coefficients (r2)≥0.9970. The limits of detection(LODs) and quantification (LOQs) were 0.2 µg/L and 0.5 µg/L, respectively. To assess the accuracy and precision of the method, we prepared milk samples with three spiked levels (low, medium, and high). The recoveries of the five veterinary drugs were ranged from 79.5% to 115%, and the intra-day and inter-day relative standard deviations were 7.0%-13% (n=6) and 1.3%-11% (n=3), respectively. This study provides a simple, accurate, and reliable method for the rapid and simultaneous determination of the five veterinary drug residues in milk.


Sujet(s)
Chitosane , Résidus de médicaments , Contamination des aliments , Spectrométrie de masse , Lait , Médicaments vétérinaires , Animaux , Lait/composition chimique , Résidus de médicaments/analyse , Chromatographie en phase liquide à haute performance , Chitosane/composition chimique , Médicaments vétérinaires/analyse , Contamination des aliments/analyse
12.
Se Pu ; 42(8): 749-757, 2024 Aug.
Article de Chinois | MEDLINE | ID: mdl-39086243

RÉSUMÉ

Tobacco flavors are extensively utilized in traditional tobacco products, electronic nicotine, heated tobacco products, and snuff. To inhibit fungal growth arising from high moisture content, preservatives such as benzoic acid (BA), sorbic acid (SA), and parabens are often incorporated into tobacco flavors. Nonetheless, consuming preservatives beyond safety thresholds may pose health risks. Therefore, analytical determination of these preservatives is crucial for both quality assurance and consumer protection. For example, BA and SA can induce adverse reactions in susceptible individuals, including asthma, urticaria, metabolic acidosis, and convulsions. Parabens, because of their endocrine activity, are classified as endocrine-disrupting chemicals. Despite extensive research, the concurrent quantification of trace-level hydrophilic (BA and SA) and hydrophobic (methylparaben, ethylparaben, isopropylparaben, propylparaben, butylparaben, isobutylparaben, and benzylparaben) preservatives in tobacco flavors remains challenging. Traditional liquid phase extraction coupled with high performance liquid chromatography (HPLC) often results in high false positive rates and inadequate sensitivity. In contrast, tandem mass spectrometry offers high sensitivity and specificity; however, its widespread application is limited by laborious sample preparation and significant operational costs. Therefore, it is crucial to establish a fast and sensitive sample pretreatment and analysis method for the nine preservatives in tobacco flavors. In this study, a method for the simultaneous determination of the nine preservatives (SA, BA and seven parabens) in tobacco flavor was established based on three phase-hollow fiber-liquid phase microextraction (3P-HF-LPME) technology combined with HPLC. To obtain the optimal pretreatment conditions, extraction solvent type, sample phase pH, acceptor phase pH, sample phase volume, extraction time, and mass fraction of sodium chloride, were examined. Additionally, the HPLC parameters, including UV detection wavelength and mobile phase composition, were refined. The optimal extraction conditions were as follows: dihexyl ether was used as extraction solvent, 15 mL sample solution (pH 4) was used as sample phase, sodium hydroxide aqueous solution (pH 12) was used as acceptor phase, and the extraction was carried out at 800 r/min for 30 min. Chromatographic separation was accomplished using an Agilent Poroshell 120 EC-C18 column (100 mm×3 mm, 2.7 µm) and a mobile phase comprising methanol, 0.02 mol/L ammonium acetate aqueous solution (containing 0.5% acetic acid), and acetonitrile for gradient elution. Under the optimized conditions, the nine target analytes showed good linear relationships in their respective linear ranges, the correlation coefficients (r) were ≥0.9967, limits of detection (LODs) and quantification (LOQs) were 0.02-0.07 mg/kg and 0.08-0.24 mg/kg, respectively. Under two spiked levels, the enrichment factors (EFs) and extraction recoveries (ERs) of the nine target analytes were 30.6-91.1 and 6.1%-18.2%, respectively. The recoveries of the nine target analytes ranged from 82.2% to 115.7% and the relative standard deviations (RSDs) (n=5) were less than 14.5% at low, medium and high levels. The developed method is straightforward, precise, sensitive, and well-suited for the rapid screening of preservatives in tobacco flavor samples.


Sujet(s)
Microextraction en phase liquide , Parabènes , Conservateurs pharmaceutiques , Chromatographie en phase liquide à haute performance , Parabènes/analyse , Microextraction en phase liquide/méthodes , Conservateurs pharmaceutiques/analyse , Acide benzoïque/analyse , Nicotiana/composition chimique , Acide sorbique/analyse , Aromatisants/analyse , Produits du tabac/analyse
13.
Se Pu ; 42(8): 799-804, 2024 Aug.
Article de Chinois | MEDLINE | ID: mdl-39086249

RÉSUMÉ

Urea is a simple organic compound that is widely used in both the industry and daily life. Compared with conventional methods, the preparation of urea by electrochemical synthesis is more environmentally friendly and sustainable. However, after the reaction, low amounts of urea and high concentrations of inorganic ions, including [Formula: see text] concentration was achieved without interference. Thus, the developed method can be applied for the detection of trace urea and other related ions in urea-containing electrolyte products.

14.
Se Pu ; 42(8): 792-798, 2024 Aug.
Article de Chinois | MEDLINE | ID: mdl-39086248

RÉSUMÉ

Sodium cyclamate in Baijiu is a key item in the China National Food Safety Supervision and Inspection Plan. A simple, economical, sensitive, and reliable method is urgently needed for routine analysis and internal quality control. A method based on high performance liquid chromatography with fluorescence detection (HPLC-FLD) was developed for the determination of sodium cyclamate in Baijiu by o-phthalaldehyde derivatization. First, the sodium cyclamate in the sample solution was converted into amino compounds using the desulfurization reaction under acidic conditions. Next, 400 g/L sodium hydroxide solution was added to the sample solution for neutralization. The amino compounds in the sample solution were then derivatized with o-phthalaldehyde to produce indole-substituted derivatives that are capable of producing fluorescence signals. Separation was carried out on a C18 column (250 mm×4.6 mm, 5 µm) in isocratic elution mode using a mobile phase consisting of acetonitrile and phosphate buffer. Finally, the eluate was monitored using a fluorescence detector, and an external standard method was used for quantification. A good linear relationship was obtained in the range of 0.1-2.0 mg/L, with correlation coefficients greater than 0.999. The average recoveries of sodium cyclamate spiked at levels of 0.1-1.0 mg/kg in Baijiu samples ranged from 90.7% to 100.9%, with relative standard deviations (RSDs) of 3.5%-5.6% (n=6). The limits of detection and quantification were 0.03 and 0.10 mg/kg, respectively. Nine Baijiu samples collected from the market were tested, and the results demonstrated that the contents of sodium cyclamate detected by the developed method were consistent with those obtained using the liquid chromatography-tandem mass spectrometry (LC-MS/MS) method described in GB 5009.97-2016 (the third method). The proposed method is economical, sensitive, specific, and accurate; thus, it provides a basic approach for the determination of sodium cyclamate in Baijiu samples and has great potential for routine analysis in foodstuffs.


Sujet(s)
Cyclamates , Fluorimétrie , Contamination des aliments , Chromatographie en phase liquide à haute performance/méthodes , Contamination des aliments/analyse , Cyclamates/analyse , Fluorimétrie/méthodes
15.
Se Pu ; 42(8): 783-791, 2024 Aug.
Article de Chinois | MEDLINE | ID: mdl-39086247

RÉSUMÉ

Quaternary ammonium salt bactericides are broad-spectrum bactericides often used in oral care products because of their high antibacterial efficacy, strong penetration, and low toxicity. However, the excessive use of quaternary ammonium salt bactericides may cause contact dermatitis, scalding poisoning, and even death. Existing methods to determine quaternary ammonium salt bactericides are unable to meet current requirements owing to the lack of determination components. Therefore, establishing a simple and accurate method for the simultaneous detection of more quaternary ammonium salt bactericides is necessary. In this study, a method that couples sample pretreatment with high performance liquid chromatography-evaporative light-scattering detection (HPLC-ELSD) was developed for the simultaneous determination of quaternary ammonium salt bactericides in oral care products, including dodecyltrimethylammonium chloride, dodecyldimethylbenzylammonium chloride, benzethonium chloride, tetradecyl trimethyl ammonium chloride, tetradecyldimethylbenzylammonium chloride, N-hexadecyltrimethylammonium chloride, benzyldimethylhexadecylammonium chloride, trimethylstearylammonium chloride, stearyldimethylbenzylammonium chloride, and docosyltrimethylammonium chloride. Some of these bactericides do not absorb ultraviolet light, so a universal evaporative light-scattering detector was used owing to testing cost and stability concerns. The paste samples contained thickening agents, which are highly soluble in water but insoluble in organic solvents; these agents can seriously affect the results of sample pretreatment and damage the chromatographic column. Hence, sample dehydration was necessary. In this study, four dehydration methods were compared. Anhydrous sodium sulfate (Na2SO4) was selected, and the amount of Na2SO4 was optimized. Based on the solubility of the 10 target compounds and extraction efficiency, three extraction solvents were compared, and ethanol was selected. Ultrasonic extraction was the primary extraction process used in this study. The effects of different ultrasonication times, temperatures, and powers on the extraction recoveries were also investigated. Ultimately, the optimized conditions were as follows: extraction of the dehydrated paste and powder samples using ethanol at room temperature (25 ℃) for 20 min under 100 W ultrasound power, and dilution of the liquid sample with ethanol. After extraction, the samples were separated on an Acclaim Surfactant column (150 mm×4.6 mm, 5 µm) with 50 mmol/L ammonium acetate aqueous solution (pH=5.5) (A) and acetonitrile (B) as mobile phases. The gradient elution program were as follows: 0-5.0 min, 75%A-35%A, 5.0-15.0 min, 35%A-20%A, 15.0-20.0 min, 20%A, 20.0-21.0 min, 20%A-75%A, 21.0-25.0 min, 75%A. An external standard method was used for quantitative determination. The 10 compounds were analyzed within 25 min. Linear equations, correlation coefficients, and linear ranges were obtained by analyzing a series of mixed standard working solutions. The limits of detection (LODs, S/N=3) and quantification (LOQs, S/N=10) of the 10 components were determined. Stearyldimethylbenzylammonium chloride and docosyltrimethylammonium chloride showed good linear relationships in the range of 10-200 mg/L, while the other compounds demonstrated good linear relationships in the range of 5-100 mg/L. In all cases, correlation coefficients (R2) of no less than 0.9992 were obtained. The LODs and LOQs were in the range of 1.42-3.31 mg/L and 4.25-9.94 mg/L, respectively. Ten analytes were spiked in blank matrices, such as toothpaste (paste), mouthwash (liquid), and dentifrice powder (powder) at three levels, and the recoveries and precisions were calculated. The average recoveries were 87.9%-103.1%, and the corresponding relative standard deviations (RSDs) did not exceed 5.5% (n=6). The developed method was used to detect 109 oral care products. Benzyldimethylhexadecylammonium chloride and stearyldimethylbenzylammonium chloride revealed high detection rates. Moreover, the amount of stearyldimethylbenzylammonium chloride in one toothpaste sample exceeded regulatory requirements. Given its advantages of good precision and accuracy, the developed method is suitable for the quantitative analysis of the 10 aforementioned compounds in typical oral care products. The study findings can serve as a reference for the quality and safety monitoring of oral care products.


Sujet(s)
Composés d'ammonium quaternaire , Composés d'ammonium quaternaire/composition chimique , Composés d'ammonium quaternaire/analyse , Chromatographie en phase liquide à haute performance , Antibactériens/analyse , Lumière , Diffusion de rayonnements
16.
Sci Rep ; 14(1): 17866, 2024 08 01.
Article de Anglais | MEDLINE | ID: mdl-39090219

RÉSUMÉ

Recently, cognitive demands in workplaces have surged significantly. This study explored the intricate relationship among mental workload (MWL), occupational fatigue, physiological responses, and cognitive performance in office workers by using collective semi-parametric models. One hundred office workers were selected from twenty offices involved in cognitive performance. MWL was assessed through the NASA Task Load Index (NASA-TLX), and occupational fatigue was measured using the Persian version of the Swedish Occupational Fatigue Inventory. Physiological responses, including respiratory rate, the electrical conductivity of the skin (ECS), Heart Rate (HR), and other heart-related parameters, were recorded from the participants during a work shift. Selective and Divided Attention tests were chosen to evaluate workers' cognitive function based on cognitive task analysis. The mean of MWL and occupational fatigue scores were 66.28 ± 11.76 and 1.62 ± 1.07, respectively. There was a significant moderate correlation between two dimensions, mental demand (0.429) and frustration (0.409), with functional fatigue. Also, Significant and, of course, nonlinear relationships were observed between MWL and HR (R2 = 0.44, P-value < 0.001) and ECS (R2 = 0.45, P-value < 0.001) and reaction time in selected (R2 = 0.34, P-value < 0.001) and divided test (R2 = 0.48, P-value < 0.001). Similarly, nonlinear relationships were observed between physiological responses and cognitive performance with fatigue among participants who had experienced higher levels of occupational fatigue. The MWL and fatigue seem to have a significant and non-linear effect on physiological parameters such as HR and ECS and cognitive parameters such as reaction time. Moreover, MWL can influence the dimension of functional fatigue of workers.


Sujet(s)
Cognition , Fatigue , Rythme cardiaque , Charge de travail , Humains , Cognition/physiologie , Charge de travail/psychologie , Mâle , Adulte , Femelle , Fatigue/physiopathologie , Rythme cardiaque/physiologie , Temps de réaction/physiologie , Lieu de travail/psychologie , Attention/physiologie , Analyse et exécution des tâches , Jeune adulte , Adulte d'âge moyen
17.
Front Vet Sci ; 11: 1436807, 2024.
Article de Anglais | MEDLINE | ID: mdl-39091388

RÉSUMÉ

Intestinal microbiota community is an important factor affecting the nutritional and health status of poultry, and its balance is crucial for improving the overall health of poultry. The study aimed to investigate the effect of dietary supplementation with Glycyrrhiza uralensis extract (GUE), Lactobacillus acidophilus (Lac) and their combination (GL) on growth performance and intestinal health in broilers in an 84-day feeding experiment. Supplementary 0.1% GUE and 4.5×107 CFU/g Lac significantly increased average daily gain (ADG), and GL (0.1% GUE and 4.5×107 CFU/g Lac) increased ADG and average daily feed intake (ADFI), and decreased feed conversion rate (FCR) in broilers aged 29 to 84 d and 1 to 84 d. Dietary GUE, Lac and GL increased the superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activity and decreased Malondialdehyde (MDA) content in the jejunum mucosa of broilers, and increased secretory IgA (sIgA) content in broilers at 84 d. Moreover, GUE, Lac and GL increased cecal microbial richness and diversity, and modulated microbial community composition. Both GUE and Lac reduced the harmful bacteria Epsilonbacteraeota, Helicobacter, and H. pullorum at 28 d and Proteobacteria, Escherichia, and E. coli at 84 d, while Lac and GL increased beneficial bacteria Lactobacillus and L. gallinarum at 28 d. Compared with individual supplementation, GL markedly increased the SOD activity and the sIgA content, and reduced Helicobacter and Helicobacter pullorum. In conclusion, GUE and Lactobacillus acidophilus as feed additives benefit growth performance and intestinal health, and their combined use shows an even more positive effect in broilers.

18.
Heliyon ; 10(13): e34158, 2024 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-39091945

RÉSUMÉ

Drawing on two theoretical frameworks-positive psychology theory and conservation of resources theory-the relationship and underlying mechanism between team-level service-oriented human resource practice (SO-HRP) bundles and team performance were explored by constructing a team-level serial mediation model. Survey data were collected from 424 employees at 80 branches of five financial holding companies in Northern Taiwan. The team-level serial-mediated model and hypotheses were examined using SPSS version 24 and the PROCESS macro for SPSS. The results indicate that team psychological capital (PsyCap) and team work engagement serially mediated the relationship between SO-HRP bundles and team performance. These results imply that managers should plan and implement SO-HRP bundles in detail, reinforce team PsyCap, and increase engagement within their financial service teams to enhance team performance.

19.
Front Sports Act Living ; 6: 1427211, 2024.
Article de Anglais | MEDLINE | ID: mdl-39092316

RÉSUMÉ

Background: In the last decade, a growing body of research has focused on the many aspects and challenges of combining parenthood with elite sport. Although the number of father-athletes is significantly higher than the number of mother-athletes, few studies to date have focused on male athletes' experiences in a parenting context. Aim: The aims of the present study were to explore how father-athlete challenges manifest among elite Nordic skiers in Norway, and to better understand how male athletes balance their priorities as they initiate, maintain, and/or discontinue their athletic career as a father-athlete. Methods: Qualitative data were collected through semi-structured interviews with 10 world-class male Nordic skiers in Norway (3 athletes without a child, 4 current father-athletes and 3 former father-athletes) and the content was analyzed using thematic analysis. Results: Four main stages were identified in the father-athlete transition: (a) Expecting incompatibility (b) Taking the step, (c), The first blow, and (d) Finding the optimal balance. Through these stages the informants expected/had experienced challenges such as performance decline, disturbed sleeping patterns, fear of sickness and role conflicts. To manage these challenges, the father-athletes had developed various strategies to balance their dual roles (e.g., adapting training and competition seasons). Among the benefits, the father-athletes mentioned that they had become more structured, time efficient and ruthless with their priorities, enhanced motivation to train and a better work-life balance. Conclusion: This study offers valuable insights into father-athlete challenges that can be used to support career longevity and work-life balance among male athletes.

20.
Cureus ; 16(7): e63634, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39092347

RÉSUMÉ

Meldonium is a substance with known anti-anginal effects demonstrated by numerous studies and human clinical trials; however, it does not possess marketing authorization within the European Union, only in ex-Soviet republics. Since 2016, meldonium has been included by the World Anti-doping Agency (WADA) on the S4 list of metabolic modulators. In performance athletes, meldonium is now considered a doping agent due to its capacity to decrease lactate production during and after exercise, its capability to enhance the storage and utilization of glycogen, and its protective action against oxidative stress. Together, these attributes can significantly improve aerobic endurance, cardiac function, and capacity as well as shorten recovery times (allowing higher intensity training), thereby enhancing performance. The purpose of this review is to highlight the most important mechanisms underlying the protective effect of meldonium against mitochondrial dysfunction (MD), which is responsible for oxidative stress, inflammation, and the cardiac changes known as "athletic heart syndrome." Meldonium acts as an inhibitor of γ-butyrobetaine hydroxylase (BBOX), preventing the de novo synthesis of carnitine and its absorption at the intestinal level via the organic cation/carnitine transporter 2 (OCTN2) and directing the oxidation of fatty acids to the peroxisomes. The decrease in mitochondrial ß-oxidation of fatty acids leads to a reduction in lipid peroxidation products that cause oxidative stress and prevent the formation of acyl/acetyl-carnitines involved in numerous pathological disorders. Given the recent findings of the potentially detrimental effects of prolonged high-intensity exercise on cardiovascular health and coronary atherosclerosis, there may be legitimate arguments for the justification of the use of substances like meldonium as protective supplements for athletes.

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