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1.
Biomacromolecules ; 25(3): 1923-1932, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38394470

RESUMO

Fatty acid cellulose esters (FACE) are common cellulose-based thermoplastics, and their thermoplasticity is determined by both the contents and the lengths of the side chains. Herein, various FACE were synthesized by the ball-milling esterification of cellulose and fatty acyl chlorides containing 10-18 carbons, and their structures and thermoplasticity were thoroughly studied. The results showed that FACE with high degrees of substitution (DS) and low melting flow temperatures (Tf) were achieved as the chain lengths of the fatty acyl chlorides were reduced. In particular, a cellulose decanoate with a DS of 1.85 and a Tf of 186 °C was achieved by feeding 3 mol of decanoyl chloride per mole anhydroglucose units of cellulose. However, cellulose stearate (DS = 1.53) synthesized by the same protocols cannot melt even at 250 °C. More interestingly, the fatty acyl chlorides with 10 and 12 carbons resulted in FACE with superior toughness (elongation at break up to 94.4%). In contrast, due to their potential crystallization of the fatty acyl groups with 14-18 carbons, the corresponding FACE showed higher tensile strength and Young's modulus than the others. This study provides some theoretical basis for the mechanochemical synthesis of thermoplastic FACE with designated properties.


Assuntos
Cloretos , Ésteres , Ésteres/química , Estudos de Viabilidade , Esterificação , Celulose/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-38870495

RESUMO

Objective: To evaluate the effectiveness of perioperative empathic care for patients with cervical cancer and its impact on their postoperative recovery and psychological well-being. Methods: A total of 196 patients diagnosed with cervical cancer and treated at our hospital between December 2019 and January 2021 were recruited and assigned via random number table method to receive either conventional nursing care (conventional group) or empathic care (experimental group), with 98 cases in each group. The inclusion criteria for cervical cancer patients were FIGO stage I-III, aged 18-65 years, and no prior cancer treatment. The empathic care provided to the experimental group involved enhanced communication, emotional support, and shared decision-making. Outcome measures included postoperative recovery indices, numeric rating scale (NRS) scores, Pittsburgh Sleep Quality Index (PSQI), Self-Rating Anxiety Scale (SAS) scores, Hamilton depression scale (HAMD) scores, and Strategies Used by People to Promote Health (SUPPH) scores. Results: Independent t tests were used to analyze the differences in postoperative recovery indices between the two groups. Patients in the experimental group who received empathic care had significantly shorter mean time to passing gas (2.35 ± 0.61 days vs. 3.41 ± 0.56 days, P < .05), shorter mean time to postoperative defecation (3.28 ± 0.71 days vs. 4.75 ± 0.63 days, P < .05), and shorter mean length of hospital stay (7.18 ± 1.04 days vs. 11.52 ± 1.25 days, P < .05) compared to the conventional group.Before the nursing intervention, there were no significant differences between the two groups in NRS scores, PSQI scores, SAS scores, HAMD scores, and SUPPH scores (all P > .05). After the nursing intervention, ANOVA was used to analyze the differences. Patients in the experimental group had lower mean NRS scores (2.96 ± 0.84 vs. 4.36 ± 1.02, P < .05), lower mean PSQI scores (8.45 ± 1.11 vs. 12.15 ± 1.52, P < .05), lower mean SAS scores (33.08 ± 3.35 vs. 47.65 ± 4.32, P < .05), and lower mean HAMD scores (30.44 ± 3.37 vs. 41.82 ± 4.05, P < .05) compared to the conventional group. Conclusion: This study demonstrates that perioperative empathic care can significantly improve postoperative recovery and psychological well-being in patients with cervical cancer. Patients receiving empathic care exhibited faster return of gastrointestinal function, shorter hospital stays, and better outcomes on measures of pain, sleep quality, anxiety, and depression. These findings suggest that incorporating empathic care into standard oncology nursing practice could have a positive impact on patient experience and clinical outcomes. Beyond the benefits for individual patients, widespread adoption of empathic care approaches has the potential to enhance the overall quality of cancer care, improve resource utilization, and contribute to more holistic, patient-centered models of healthcare delivery. Further research is warranted to evaluate the long-term effects of empathic care and its applicability across diverse oncology populations.

3.
Sensors (Basel) ; 24(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38610291

RESUMO

Deep transfer learning has been widely used to improve the versatility of models. In the problem of cross-domain fault diagnosis in rolling bearings, most models require that the given data have a similar distribution, which limits the diagnostic effect and generalization of the model. This paper proposes a deep reconstruction transfer convolutional neural network (DRTCNN), which satisfies the domain adaptability of the model under cross-domain conditions. Firstly, the model uses a deep reconstruction convolutional automatic encoder for feature extraction and data reconstruction. Through sharing parameters and unsupervised training, the structural information of target domain samples is effectively used to extract domain-invariant features. Secondly, a new subdomain alignment loss function is introduced to align the subdomain distribution of the source domain and the target domain, which can improve the classification accuracy by reducing the intra-class distance and increasing the inter-class distance. In addition, a label smoothing algorithm considering the credibility of the sample is introduced to train the model classifier to avoid the impact of wrong labels on the training process. Three datasets are used to verify the versatility of the model, and the results show that the model has a high accuracy and stability.

4.
J Environ Sci (China) ; 143: 189-200, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38644016

RESUMO

Microbial activity and interaction are the important driving factors in the start-up phase of food waste composting at low temperature. The aim of this study was to explore the effect of inoculating Bacillus licheniformis on the degradation of organic components and the potential microbe-driven mechanism from the aspects of organic matter degradation, enzyme activity, microbial community interaction, and microbial metabolic function. The results showed that after inoculating B. licheniformis, temperature increased to 47.8°C on day 2, and the degradation of readily degraded carbohydrates (RDC) increased by 31.2%, and the bioheat production increased by 16.5%. There was an obvious enhancement of extracellular enzymes activities after inoculation, especially amylase activity, which increased by 7.68 times on day 4. The inoculated B. licheniformis colonized in composting as key genus in the start-up phase. Modular network analysis and Mantel test indicated that inoculation drove the cooperation between microbial network modules who were responsible for various organic components (RDC, lipid, protein, and lignocellulose) degradation in the start-up phase. Metabolic function prediction suggested that carbohydrate metabolisms including starch and sucrose metabolism, glycolysis / gluconeogenesis, pyruvate metabolism, etc., were improved by increasing the abundance of related functional genes after inoculation. In conclusion, inoculating B. licheniformis accelerated organic degradation by driving the cooperation between microbial network modules and enhancing microbial metabolism in the start-up phase of composting.


Assuntos
Bacillus licheniformis , Compostagem , Bacillus licheniformis/metabolismo , Compostagem/métodos , Microbiologia do Solo , Biodegradação Ambiental , Microbiota/fisiologia , Temperatura Baixa
5.
PLoS One ; 19(5): e0303387, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38728351

RESUMO

Heavy metal pollution in farmland soil represents a considerable risk to ecosystems and human health, constituting a global concern. Focusing on a key area for the cultivation of special agricultural products in Cangxi County, we collected 228 surface soil samples. We analyzed the concentration, spatial distribution, and pollution levels of six heavy metals (Cr, Cu, Pb, Ni, Zn, and Hg) in the soil. Moreover, we investigated the sources and contribution rates of these heavy metals using Principal Component Analysis/Absolute Principal Component Scores (PCA/APCS) and Positive Matrix Factorization (PMF) models. Our findings indicate that none of the six metals exceeded the pollution thresholds for farmland soils. However, the mean concentrations of Cr and Ni surpassed the background levels of Sichuan Province. A moderate spatial correlation existed between Pb and Ni, attributable to both natural and anthropogenic factors, whereas Zn, Cu, Hg, and Cr displayed a strong spatial correlation, mainly due to natural factors. The spatial patterns of Cr, Cu, Zn, Pb, and Ni were similar, with higher concentrations in the northern and eastern regions and lower concentrations centrally. Hg's spatial distribution differed, exhibiting a broader range of lower values. The single pollution index evaluation showed that Cr and Ni were low pollution, and the other elements were no pollution. The average value of comprehensive pollution index is 0.994, and the degree of pollution is close to light pollution. Predominantly, higher pollution levels in the northern and eastern regions, lower around reservoirs. The PCA/APCS model identified two main pollution sources: agricultural traffic mixed source (65.2%) and natural parent source (17.2%). The PMF model delineated three sources: agricultural activities (32.59%), transportation (30.64%), and natural parent sources (36.77%). Comparatively, the PMF model proved more accurate and reliable, yielding findings more aligned with the study area's actual conditions.


Assuntos
Agricultura , Metais Pesados , Poluentes do Solo , Solo , Metais Pesados/análise , China , Poluentes do Solo/análise , Solo/química , Monitoramento Ambiental/métodos , Análise de Componente Principal , Análise Espacial
6.
Cancers (Basel) ; 16(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38610923

RESUMO

To develop ultrasound-guided radiotherapy, we proposed an assistant structure with embedded markers along with a novel alternative method, the Aligned Peak Response (APR) method, to alter the conventional delay-and-sum (DAS) beamformer for reconstructing ultrasound images obtained from a flexible array. We simulated imaging targets in Field-II using point target phantoms with point targets at different locations. In the experimental phantom ultrasound images, image RF data were acquired with a flexible transducer with in-house assistant structures embedded with needle targets for testing the accuracy of the APR method. The lateral full width at half maximum (FWHM) values of the objective point target (OPT) in ground truth ultrasound images, APR-delayed ultrasound images with a flat shape, and images acquired with curved transducer radii of 500 mm and 700 mm were 3.96 mm, 4.95 mm, 4.96 mm, and 4.95 mm. The corresponding axial FWHM values were 1.52 mm, 4.08 mm, 5.84 mm, and 5.92 mm, respectively. These results demonstrate that the proposed assistant structure and the APR method have the potential to construct accurate delay curves without external shape sensing, thereby enabling a flexible ultrasound array for tracking pancreatic tumor targets in real time for radiotherapy.

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