The radical copolymerization was used to synthesize cationic acrylic resin, which the methyl methacrylate (MMA) was used as the main hard monomer and styrene (St) was added to replace the function of ...MMA to reduce the cost of raw materials. Butyl acrylate (BA) was used as the main soft monomer to reduce the glass transition temperature of the polymer. Hydroxypropyl methacrylate (HPMA) was used to provide cross-linked hydroxyl groups for resin, and hydroxyl groups also had a certain hydrophilic properties. Dimethylaminoethyl methacrylate (DMAEMA) was used to provide tertiary amine group for the resin, which was acidified by organic acid to form ammonium salt. The cathodic electrodeposition (CED) coatings were prepared by mixing the resultant resin and blocked isocyanate. The conditions of synthesizing the cationic acrylic resin were optimized. The optimum synthetic conditions were the following. The mass ratio of (MMA + St) to BA was 3:2. The amount of DMAEMA was 12–15% in total monomer. The amount of HPMA was 20% in total monomer. The amount of the initiator was 2%. The neutralization degree was 80%. The reaction temperature was 90 °C. Both the conductivity of electrophoretic coating and its film were good when the cationic acrylic resin was synthesized under the optimum conditions. Besides, the characterization of Fourier transform infrared spectrometer (FTIR) and differential scanning calorimetry (DSC) confirmed that the cationic acrylic resin had been synthesized successfully.
In this paper, tung oil-linseed oil (TO-LSO) and styrene-linseed oil (STY-LSO) were used as raw materials of sulfur-rich copolymers, which were then reversed vulcanized with S
8
at 130°C, and the gel ...time of the reaction was recorded. At the same time,
1
H NMR, DSC, XRD, sodium sulfite titration and other characterization methods were used to measure the reaction degree, verify the conjugated structure to improve the reaction degree, and study the synthesis mechanism of sulfur-rich copolymer. The results show that the conjugated structure can improve the reaction degree. And when the proportion of TO and STY is 20 and 10% respectively, the reaction gel time is shortened, the reaction degree is greatly deepened, and the effect of promoting polymerization can be significantly obtained. The synthesis mechanism of copolymer is the result of conjugated structure and diallyl group. The self-repair of sulfur-rich copolymers at different temperature and holding time by hot press shows that poly(20-TO-LSO-50S) can realize the S‒S bond self-repair after being compressed at 120°C for 4 h, and the surface of polymer disc was smoother and more uniform. However, poly(10STY-LSO-50S) can be repaired only after being compressed for 8 h. TO can not only enhance the synthesis process, but also enhance the performance of sulfur-rich materials and broaden the application field.
Thiopurine therapy, commonly used in autoimmune conditions, can be complicated by life-threatening leukopenia. This leukopenia is associated with genetic variation in TPMT (encoding thiopurine ...S-methyltransferase). Despite a lower frequency of TPMT mutations in Asians, the incidence of thiopurine-induced leukopenia is higher in Asians than in individuals of European descent. Here we performed an Immunochip-based 2-stage association study in 978 Korean subjects with Crohn's disease treated with thiopurines. We identified a nonsynonymous SNP in NUDT15 (encoding p.Arg139Cys) that was strongly associated with thiopurine-induced early leukopenia (odds ratio (OR) = 35.6; P(combined) = 4.88 × 10(-94)). In Koreans, this variant demonstrated sensitivity and specificity of 89.4% and 93.2%, respectively, for thiopurine-induced early leukopenia (in comparison to 12.1% and 97.6% for TPMT variants). Although rare, this SNP was also strongly associated with thiopurine-induced leukopenia in subjects with inflammatory bowel disease of European descent (OR = 9.50; P = 4.64 × 10(-4)). Thus, NUDT15 is a pharmacogenetic determinant for thiopurine-induced leukopenia in diverse populations.
Abstract
Study Objectives
Mobility restrictions imposed to suppress transmission of COVID-19 can alter physical activity (PA) and sleep patterns that are important for health and well-being. ...Characterization of response heterogeneity and their underlying associations may assist in stratifying the health impact of the pandemic.
Methods
We obtained wearable data covering baseline, incremental mobility restriction, and lockdown periods from 1,824 city-dwelling, working adults aged 21–40 years, incorporating 206,381 nights of sleep and 334,038 days of PA. Distinct rest-activity rhythm (RAR) profiles were identified using k-means clustering, indicating participants’ temporal distribution of step counts over the day. Hierarchical clustering of the proportion of days spent in each of these RAR profiles revealed four groups who expressed different mixtures of RAR profiles before and during the lockdown.
Results
Time in bed increased by 20 min during the lockdown without loss of sleep efficiency, while social jetlag measures decreased by 15 min. Resting heart rate declined by ~2 bpm. PA dropped an average of 42%. Four groups with different compositions of RAR profiles were found. Three were better able to maintain PA and weekday/weekend differentiation during lockdown. The least active group comprising ~51% of the sample, were younger and predominantly singles. Habitually less active already, this group showed the greatest reduction in PA during lockdown with little weekday/weekend differences.
Conclusion
In the early aftermath of COVID-19 mobility restriction, PA appears to be more severely affected than sleep. RAR evaluation uncovered heterogeneity of responses to lockdown that could associate with different outcomes should the resolution of COVID-19 be protracted.
Rheological properties play a crucial role in characterizing 3D printed cement-based materials. To further investigate the mechanism behind rheological evolution, this study employs low-field NMR ...relaxation time measurement to characterize the microstructure evolution of 3D printed steel slag cementitious material within the first 6 hours. This is combined with rheological parameters to explore the relationship between the mixture's rheological properties and pore microstructure over time. The results demonstrate that relaxation time effectively represents the temporal characteristics of rheological parameters, while pore throat distribution (0–0.1μm) exhibits a positive correlation with plastic viscosity. Low-field NMR relaxation characteristics can effectively describe early properties of 3D printed cementitious materials and provide valuable data support for future exploration of non-destructive testing during early stages.
Background
Aquatic ecosystems are considered to be among the most important reservoirs of antibiotic resistance genes (ARGs). Drinking water sources could serve as critical points of ARGs transfer ...from environment to human. In this study, the distribution of antibiotics and ARGs across Qingcaosha Reservoir located in the Yangtze River Delta during three seasons was investigated to characterize the pollution patterns.
Results
Sulfamethoxazole, sulfamonomethoxine and penicillin G potassium salt were the dominant antibiotics in this reservoir. Sulfonamide resistance genes (
sul1
and
sul2
) were the most prevalent and predominant genes. Higher total relative abundance of the ARGs was detected in the site closest to the inflow than those in other sites. Overall, the concentrations of antibiotics in May were relatively lower than those in November and February. Correlation analysis indicated
sul1
,
ermB
and
mphA
had positive correlation with corresponding antibiotics in February and
sul1
,
sul2
,
ermB
and
mphA
was also positively correlated to
intI1
.
Conclusion
In conclusion, antibiotics and ARGs were widespread in Qingcaosha Reservoir. Our results indicated that the drinking water reservoir might serve as gene reservoir for antibiotic resistance and mobile gene element
intI1
can serve as a medium to contribute to the widespread of various ARGs. As the ARGs abundance was found to be higher in the inflow of the reservoir compared to the outflow, it is considered that reservoir could serve as a functional area contributing to the elimination or dilution of ARGs.
Calcium alginate (CaAlg) is a kind of biodegradable and eco-friendly functional material, and CaAlg/reduced graphene oxide (rGO) composites are expected to be applied as new textile, heat-generating, ...and flame-retardant materials. In this paper, the CaAlg/rGO composites were prepared by a sol-gel method and their morphological and thermal properties were studied. The results showed that the introduction of rGO can efficiently improve the thermal stability of CaAlg. Further study showed that rGO increased the carbon formation rate by 4.1%, indicating that the thermal stability was improved by the promotion of carbon formation. Moreover, the weight loss rate of the composites was faster at 180⁻200 °C than that of CaAlg, after which the rate was less comparatively, suggesting the better thermal stability of the composite. This maybe because the high heat transfer efficiency of rGO allowed the material to reach the temperature of the thermal decomposition of the glycan molecule chain within a short time, and then promoted carbon formation. The thermal cracking mechanism of the composites is proposed based on the experimental data.
The aim of this study was to examine the correlation between the level of mobile phone dependence among college students and their experience of academic burnout. Additionally, the study sought to ...explore the potential mediating effect of study engagement and the moderating role of love.
During October and December 2023, a cross-sectional study measuring mobile phone dependence, academic burnout, and study engagement among Chinese college students, using the UtrechtWork Engagement Scale-student (UWES-S), College Student Mobile Phone Dependence Questionnaire (CSMPDQ), and Academic Burnout Questionnaire (ABQ). To examine the hypothesis of mediating and moderating effect, SPSS PROCESS was utilized.
The predictive effect of mobile phone dependence on academic burnout was significant (
= 0.410,
= 14.236,
< 0.001), and the predictive effect of mobile phone dependence on academic burnout remained significant when the mediating variable study engagement was introduced (
= 0.308,
= 10.288,
< 0.001), mobile phone dependence had a significant predictive effect on study engagement (
= -0.292,
= -11.639,
< 0.001), and study engagement had a significant positive predictive effect on academic burnout (
= -0.270,
= -9.028,
< 0.001). Love significantly negatively predicted study engagement (
= -0.564,
= -9.641,
< 0.001); and the interaction term for mobile phone dependence and love was significant (
= -0.211,
= -3.688,
< 0.001), indicating a significant moderating effect of love between mobile phone dependence and study engagement.
Mobile phones among college students has been found to have a direct correlation with academic burnout. It can also indirectly contribute to academic burnout by diminishing levels of academic engagement. This indirect relationship is further influenced by love. These findings can help researchers and educators better understand the underlying mechanisms between smartphone dependence and learning burnout in undergraduates.
The novel and efficient lignin-based CO2 bio-absorbent was fabricated by Mannich reaction,which verified the synergistic absorption mechanism of CO2 based on multiple active sites.
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...High and cost-efficient capture of CO2 is a prerequisite and an inevitable path of carbon emission reduction. To address the challenges (high cost, low efficiency, less sustainability, etc.) of existing petroleum-based CO2 absorbents, herein, a class of efficient and sustainable lignin-based absorbents were resoundingly prepared by grafting the active amine group on a lignin derived compound vanillin and alkali lignin. The results demonstrated that vanillin modified by acrylamide achieved the excellent absorption capacity among the three absorbents, whose ability was 0.114 g CO2 per gram of absorbent under 25 °C and 100 kPa.In addition, the absorbent retained stable absorbability of CO2 after 6 cycles. The absorbing capacity of the absorbent formed by the coupling of vanillin and acrylamide to CO2 was much greater than their own (i.e. 0 g CO2·g−1 vanillin, 0.01 g CO2·g−1 acrylamide, respectively). Detailed information revealed the multi-site synergistic absorption mechanism, in which CO2 has C and O double interactions with the amide group of the absorbent, and single interaction with the hydroxyl oxygen on the benzene ring of the absorbent. The absorption capacity of modified lignin for CO2 is as high as 0.12 g CO2 per gram of absorbent, which is comparable with that of model compound vanillin. This work not only provides a new idea for the design of bio-absorbents for CO2 capture, but explores the application potential of lignin-based materials.
An enhanced dung beetle optimization algorithm (EDBO) is proposed for nonlinear optimization problems with multiple constraints in manufacturing. Firstly, the dung beetle rolling phase is improved by ...removing the worst value interference and coupling the current solution with the optimal solution to each other, while retaining the advantages of the original formulation. Subsequently, to address the problem that the dung beetle dancing phase focuses only on the information of the current solution, which leads to the overly stochastic and inefficient exploration of the problem space, the globally optimal solution is introduced to steer the dung beetle, and a stochastic factor is added to the optimal solution. Finally, the dung beetle foraging phase introduces the Jacobi curve to further enhance the algorithm’s ability to jump out of the local optimum and avoid the phenomenon of premature convergence. The performance of EDBO in optimization is tested using the CEC2017 function set, and the significance of the algorithm is verified by the Wilcoxon rank-sum test and the Friedman test. The experimental results show that EDBO has strong optimization-seeking accuracy and optimization-seeking stability. By solving four engineering optimization problems of varying degrees, EDBO has proven to have good adaptability and robustness.
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