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Using biodegradable films as a substitute for conventional polyolefin films has emerged as a crucial technology to combat agricultural white pollution. To address the shortcomings in the tensile strength, water vapor barrier properties, and degradation period of PBAT-based biodegradable films, this investigation aimed to create a composite film that could improve the diverse properties of PBAT films. To achieve this, a PBAT/PLA-PPC-PTLA ternary blend system was introduced in the study. The system effectively fused PBAT with PLA and PPC, as evidenced by electron microscopy tests showing no apparent defects on the surface and cross-section of the blended film. The developed ternary blend system resulted in a 58.62% improvement in tensile strength, a 70.33% enhancement in water vapor barrier properties, and a 30-day extension of the functional period compared to pure PBAT biodegradable films. Field experiments on corn crops demonstrated that the modified biodegradable film is more suitable for agricultural production, as it improved thermal insulation and moisture retention, leading to a 5.45% increase in corn yield, approaching the yield of traditional polyolefin films.
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This study delves into the interplay between learning motivation, organizational performance, and the innovative climate within Chinese firms. It is a subject of frequent discussion in literature but there is little concrete evidence supporting this viewpoint within the context of small and medium size enterprises in China. Drawing upon a comprehensive review of existing literature and empirical data gathered, this research aims to uncover the connections between employee learning motivation and its impact on the organizational dynamics in the context of Chinese firms. A cross sectional survey is used to collect the data of 115 Chinese firms and structural equation modelling (SEM) is used for empirical analysis. The results show that success of firms in terms of innovation is significantly influenced by organizational learning motivation. Moreover, innovative environment of the firms increases the overall performance of the organizations. It is also found that factors affecting the innovations have a significant impact on organizational performance. The findings of the study suggest that firms should develop organizational learning motivation to boost their innovation capability and overall performance. This study offers insights and recommendations for organizations and policymakers seeking to harness the potential of learning motivation to drive sustainable growth, competitiveness, and innovation in Chinese firms.
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Aprendizagem , Motivação , Cultura Organizacional , China , Humanos , Estudos Transversais , Inovação Organizacional , Inquéritos e Questionários , Masculino , Feminino , AdultoRESUMO
Bemisia tabaci is distributed globally and incurs considerable economic and ecological costs as an agricultural pest and viral vector. The entomopathogenic fungus Metarhizium anisopliae has been known for its insecticidal activity, but its impacts on whiteflies are understudied. We investigated how infection with the semi-persistently transmitted Cucurbit chlorotic yellows virus (CCYV) affects whitefly susceptibility to M. anisopliae exposure. We discovered that viruliferous whiteflies exhibited increased mortality when fungus infection was present compared to non-viruliferous insects. High throughput 16S rRNA sequencing also revealed significant alterations of the whitefly bacterial microbiome diversity and structure due to both CCYV and fungal presence. Specifically, the obligate symbiont Portiera decreased in relative abundance in viruliferous whiteflies exposed to M. anisopliae. Facultative Hamiltonella and Rickettsia symbionts exhibited variability across groups but dominated in fungus-treated non-viruliferous whiteflies. Our results illuminate triangular interplay between pest insects, their pathogens, and symbionts-dynamics which can inform integrated management strategies leveraging biopesticides This work underscores the promise of M. anisopliae for sustainable whitefly control while laying the groundwork for elucidating mechanisms behind microbe-mediated shifts in vector competence.
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Objective: Opioid-sparing anesthesia reduces intraoperative use of opioids and postoperative adverse reactions. The current study investigated the effect of esketamine-based opioid-sparing anesthesia on total laparoscopic hysterectomy patients' recovery. Methods: Ninety patients undergoing total laparoscopic hysterectomy were randomly assigned to esketamine-based group (group K) or opioid-based group (group C). The allocation to groups was unknown to patients, surgeons, and postoperative medical staff. The inability to implement blinding for anesthesiologists was due to the distinct procedures followed by the various groups while administering drugs. The QoR-40 and VAS were used to measure recovery quality. Postoperative adverse events, perioperative opioid consumption, and intraoperative hemodynamics were secondary endpoints. Results: There was an absence of notable discrepancy in the baseline data observed between the two groups. The QoR-40 scores exhibited greater values in group K when compared to group C on the first day following the surgical procedure (160.91 ± 9.11 vs 151.47 ± 8.35, respectively; mean difference 9.44 [95 %CI: 5.78-13.11]; P < 0.01). Within 24 h of surgery, the VAS score of group K was lower at rest and during movement. (P < 0.05 for each). Group K had much lower rates of nausea and vomiting within 24 h of surgery. (P < 0.05 for each). Group K received significantly lower total doses of sufentanil and remifentanil than group C. (17.28 ± 2.59 vs 43.43 ± 3.52; 0.51 ± 0.15 vs 1.24 ± 0.24). The proportion of patients who used ephedrine in surgery was higher in group C than in group K (P < 0.05). Conclusions: Esketamine-based opioid-sparing anesthesia strategy is feasible and enhanced recuperation following surgery by decreasing adverse effects associated with opioids and pain scores compared to an opioid-based anesthetic regimen.
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Typical small organic dyes exhibit excellent UV absorption capabilities and are commonly used as additives to shield plastic films from photoaging. However, their tendency to decompose easily and migrate rapidly within a polymer matrix limits their service life. Herein we prepared g-C3N4 nanosheets and fabricated g-C3N4/PBAT films to investigate the effects of g-C3N4 on UV shielding and plasticizing of a biodegradable PBAT film. Photophysical characterizations revealed that an improved UV light barrier performance was achieved on g-C3N4/PBAT films compared to pure PBAT. Furthermore, the photoaging results show that g-C3N4 can stably exist in the PBAT matrix, enabling the aged g-C3N4/PBAT films to maintain their effective UV shielding ability, whereas the aged benzophenone (UV-0)/PBAT film shows a substantial decrease in UV light absorption due to the photodecomposition of UV-0. Additionally, g-C3N4 acted as a reinforcing material for PBAT, as evidenced by the approximately 1.5-fold increase in longitudinal tear strength and 1.6-fold increase in tensile strength of g-C3N4/PBAT films compared to pure PBAT. Remarkably, even after 100 hours of photoaging, the aged g-C3N4/PBAT films retained their favorable mechanical properties. This study highlights the potential of g-C3N4 as a new type of UV shield additive for future practical applications in protecting biodegradable plastic from photoaging.
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Nonspecific adsorption has always been a critical challenge for sensor detection; thus, an efficient and facile approach for fabricating antifouling sensors is highly desirable. Here, we developed an antifouling coating on sensor surfaces, conveniently made with a simple drip of phase-transited BSA (PTB) followed by a modification with a peanut allergen antibody, which unexpectedly provides synergistic antifouling properties in sensors. Atomic force microscopy and scanning electron microscopy were used to evaluate the surface evenness. Optimizations in terms of PTB modification time and concentrations were performed using surface plasmon resonance by measuring protein resistance capabilities. Compared to bare Au surfaces, the PTB-modified surfaces exhibited low adsorption against BSA (<10 ng/cm2) and good resistance against lysozyme (Lyz). After immobilizing antibodies, the antifouling performance of the sensor coatings had an obvious enhancement, with almost no BSA adsorption and low lysozyme adsorption. The target recognition was also analyzed to verify the good sensing performance of the antifouling sensor. This understanding of antibody synergy provides suggestions for the development of antifouling sensors.
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Incrustação Biológica , Muramidase , Anticorpos , Proteínas , Ressonância de Plasmônio de Superfície , Propriedades de SuperfícieRESUMO
Anthocyanins (ANs) have strong antioxidant activities and can inhibit chronic diseases, but the instability of ANs limits their applications. The conservation of preheating whey protein concentrate (WPC) on the stability of purple sweet potato ANs was investigated. The retention of ANs in WPC-ANs was 85.88% after storage at 25 °C for 5 h. WPC-ANs had higher retention of ANs in heating treatment. The retention rates of ANs in WPC-ANs exposed to light and UV lamps for 6 h were 78.72% and 85.76%, respectively. When the concentration of H2O2 was 0.50%, the retention rate of ANs in the complexes was 62.04%. WPC-ANs' stability and antioxidant activity were improved in simulated digestive juice. The WPC-ANs connection was static quenching, and the binding force between them was a hydrophobic interaction at one binding site, according to the fluorescence quenching spectroscopy. UV-visible absorption spectroscopy and Fourier transform infrared spectroscopy (FTIR) analysis further indicated that the secondary structure and microenvironment of amino acid residues in WPC can be impacted by the preheating temperature and preheating times of WPC. In conclusion, preheating WPC can successfully preserve the stability of purple sweet potato ANs by binding to them through a non-covalent interaction.
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In this study, the effect of chickpea dietary fiber (CDF) concentration (0%, 0.4%, 0.8%, 1.2%, 1.6%, and 2.0%) on emulsion gel properties of myofibrillar protein (MP) was investigated. It was found that the emulsifying activity index (EAI) and emulsifying stability index (ESI) of MP increased with the increasing content of CDF. Moreover, the water- and fat-binding capacity (WFB), gel strength, storage modulus (G'), and loss modulus (G") of MP emulsion gel also increased with increasing content of CDF. When the concentration of CDF was 2%, the most significant improvement was observed for EAI, breaking force, and WFB (p < 0.05); the three-dimensional gel network structure of the MP emulsion gel was denser and the pore diameter was smaller. The T21 relaxation time of emulsion gel decreased while the PT21 increased significantly with the increasing content of CDF, suggesting that the emulsion gel with CDF had a better three-dimension network. The addition of CDF led to an increased content of ß-sheet and reactive sulfhydryl and increased surface hydrophobicity of MP, thus improving the gel properties of the MP emulsion gel. In conclusion, the addition of CDF improved the functional properties and facilitated the gelation of the MP emulsion, indicating that CDF has the potential to improve the quality of emulsified meat products.
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To optimize the bamboo heat treatment process, the corresponding evolution rules under various heat treatment conditions must be determined. When the heat treatment time and temperature remained constant, the effects of different heat treatment pressures on the equilibrium moisture content, dimensional stability, mechanical properties, and chemical composition of bamboo were systematically investigated. In this experiment, bamboo without heat treatment was used as the control group. The experimental findings demonstrate the following: (1) The equilibrium moisture content of heat-treated bamboo gradually decreases with increasing treatment pressure. When the heat treatment pressure was set at 0.1, 0.15, 0.2, and 0.25 MPa, the bamboo's equilibrium water content decreased to 12.1%, 11.7%, 9.9%, and 8.6%, respectively, while that of the control group was 13.8%. (2) The dimensional stability of bamboo was enhanced with increasing heat treatment pressure. At pressures of 0.1, 0.15, 0.2, and 0.25 MPa, the radial air-dry shrinkage rates of the heat-treated bamboo decreased to 3.4%, 3.4%, 2.6%, and 2.3%, respectively, while the tangential air-dry shrinkage rates reduced to 5.6%, 5.1%, 3.3%, and 3.0%. In comparison, the radial and tangential air-dry shrinkage rates of the control group were measured as 3.6% and 5.8%, respectively. Similarly, the radial and tangential full-dry shrinkage of bamboo exhibited a similar trend. (3) With the increase in heat treatment pressure, the bending strength and longitudinal compressive strength of bamboo exhibited an initial rise followed by a decline. When it was at heat treatment pressures of 0.1, 0.15, 0.2, and 0.25 MPa, the corresponding bending strengths of the heat-treated bamboo were measured as 41.2, 26.7, 22.4, and 20.4 MPa, respectively; while the longitudinal compressive strengths were recorded as 42.6, 38.1, 29.1, and 25.3 MPa. In comparison, the bending and longitudinal compressive strengths of the control group were measured as 39.8 and 38.5 MPa, respectively. It is evident that the optimal heat treatment pressure for bamboo is 0.1 MPa, resulting in a significant increase of 3.5% and 10.6% in bending strength and longitudinal compressive strength, respectively, compared to the control group. (4) Based on the FTIR and XRD patterns of bamboo samples, a range of physical and chemical transformations were observed during the heat treatment process, including cellulose adsorb water evaporation, hemicellulose and cellulose degradation, as well as acetyl group hydrolysis on the molecular chain of hemicellulose. These changes collectively impacted the physical and mechanical properties of bamboo.
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Solar-driven electrochemical NO3- reduction reaction (NO3-RR) is a clean and sustainable strategy that can convert pollutant NO3- in wastewater to value-added NH3. In recent years, cobalt oxides-based catalysts have shown their intrinsic catalytic properties toward NO3-RR but still have room for improvement through catalyst design. Coupling metal oxides with noble metal has been demonstrated to improve electrochemical catalytic efficiency. Here, we use Au species to tune the surface structure of Co3O4 and improve the efficiency of NO3-RR to NH3. The obtained Au nanocrystals-Co3O4 catalyst exhibited an onset potential of 0.54 V vs RHE, NH3 yield rate of 27.86 µg/h·cm2, and Faradaic efficiency (FE) of 83.1% at 0.437 V vs RHE in an H-cell, which is much higher than Au small species (Au clusters or single atoms)-Co3O4 (15.12 µg/h·cm2) and pure Co3O4 (11.38 µg/h·cm2), respectively. Combined experiments with theory calculations, we attributed the enhanced performance of Au nanocrystals-Co3O4 to the reduced energy barrier of *NO hydrogenation to the *NHO and suppression of HER, which originated from the charge transfer from Au to Co3O4. Using an amorphous silicon triple-junction (a-Si TJ) as the solar cell and an anion exchange membrane electrolyzer (AME), an unassisted solar-driven NO3-RR to NH3 prototype was realized with a yield rate of 4.65 mg/h and FE of 92.1%.
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Objective: Bilirubin has anti-inflammatory, antioxidant, and neuroprotective properties, but the association between bilirubin and stroke remains contentious. A meta-analysis of extensive observational studies on the relationship was conducted. Methods: Studies published before August 2022 were searched in PubMed, EMBASE, and Cochrane Library. Cohort, cross-sectional and case-control studies that examined the association between circulating bilirubin and stroke were included. The primary outcome included the incidence of stroke and bilirubin quantitative expression level between stroke and control, and the secondary outcome was stroke severity. All pooled outcome measures were determined using random-effects models. The meta-analysis, subgroup analysis, and sensitivity analysis were performed using Stata 17. Results: A total of 17 studies were included. Patients with stroke had a lower total bilirubin level (mean difference = -1.33 µmol/L, 95% CI: -2.12 to -0.53, P < 0.001). Compared with the lowest bilirubin level, total odds ratio (OR) of the highest bilirubin for the occurrence of stroke was 0.71 (95% CI: 0.61-0.82) and ischemic stroke was 0.72 (95% CI: 0.57-0.91), especially in cohort studies with accepted heterogeneity (I 2 = 0). Serum total and direct bilirubin levels were significantly and positively associated with stroke severity. A stratified analysis based on gender showed that the total bilirubin level in males correlated with ischemic stroke or stroke, which was not noted in females. Conclusion: While our findings suggest associations between bilirubin levels and stroke risk, existing evidence is insufficient to establish a definitive association. Better-designed prospective cohort studies should further clarify pertinent questions (PROSPERO registration number: CRD42022374893).
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Specificity and efficiency of plant virus transmission depend largely on protein-protein interactions of vectors and viruses. Cucurbit chlorotic yellows virus (CCYV), transmitted specifically by tobacco whitefly, Bemisia tabaci, in a semi-persistent manner, has caused serious damage on cucurbit and vegetable crops around the world. However, the molecular mechanism of interaction during CCYV retention and transmission are still lacking. CCYV was proven to bind particularly to the whitefly foregut, and here, we confirmed that the minor coat protein (CPm) of CCYV is participated in the interaction with the vector. In order to identify proteins of B. tabaci that interact directly with CPm of CCYV, the immunoprecipitation (IP) assay and DUALmembrane cDNA library screening technology were applied. The cytochrome c oxidase subunit 5A (COX), tubulin beta chain (TUB) and keratin, type I cytoskeletal 9-like (KRT) of B. tabaci shown strong interactions with CPm and are closely associated with the retention within the vector and transmission of CCYV. These findings on whitefly protein-CCYV CPm interactions are crucial for a much better understanding the mechanism of semi-persistent plant virus transmission by insect vectors, as well as for implement new strategies for effective management of plant viruses and their vector insects.
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Crinivirus , Hemípteros , Animais , Capsídeo/metabolismo , Hemípteros/metabolismo , Vírion , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Crinivirus/genética , Crinivirus/metabolismo , Doenças das PlantasRESUMO
Polycaprolactone (PCL) is one of the promising linear aliphatic polyesters which can be used as mulching film. Although it has suitable glass transition temperature and good biodegradability, further practical applications are restricted by the limited temperature-increasing and moisturizing properties. The rational design of the PCL structure is a good strategy to enhance the related properties. In this study, thermally-induced phase separation (TIPS) was introduced to fabricate a PCL nanoporous thin film. The introduction of a nanoporous structure on the PCL surface (np-PCL) exhibited enhanced temperature-increasing and moisturizing properties when used as mulch film. In detail, the average soil temperature of np-PCL was increased to 17.81 °C, when compared with common PCL of 17.42 °C and PBAT of 17.50 °C, and approaches to PE of 18.02 °C. In terms of water vapor transmission rate, the value for np-PCL is 637 gm-2day-1, which was much less than the common PCL of 786 and PBAT of 890 gm-2day-1. As a result, the weed biomass under the np-PCL was suppressed to be 0.35 kg m-2, almost half of the common PCL and PBAT. In addition, the np-PCL shows good thermal stability with an onset decomposition temperature of 295 °C. The degradation mechanism and rate of the np-PCL in different pH environments were also studied to explore the influence of nanoporous structure. This work highlights the importance of the nanoporous structure in PCL to enhance the temperature-increasing and moisturizing properties of PCL-based biodegradable mulching film.
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Biodegradable mulches (BDMs) are considered promising alternative green materials to achieve the substitution of polythene (PE) films to reduce plastic pollution. However, whether the BDMs are sufficiently effective to promote cotton production as PE film is a controversial topic. In this study, laboratory determination and field experiments were conducted with one pure Poly(butylene adipate-co-terephthalate) (PBAT) film (BDM), two commercial PBAT-based films (BDM1 and BDM2), and one PE film to (â °) compare the degradation behavior, morphology, and property changes during field application, and (â ±) reveal their effects on biomass accumulation and cotton yield. Degradation behavior, degradation rate, structure, thermal stability, crystallinity, and molecular weight changes of the films before and after mulching were investigated and characterized. Water vapor transmission rate and mechanical properties of the films and the effects these on soil temperature, crop growth, and cotton yield were discussed. Results show that the three PBAT-based mulch films gradually degraded during mulching. The molecular weight, thermal stability, and crystallinity of BDM1 and BDM2 decreased. Interestingly, BDM showed the opposite characteristics, but the degradation degree was greatest at harvest. PE film showed no significant changes in its microscopic appearance, thermal performance, or properties. These PBAT-based films were positively correlated with the complete coverage period of the films. In-depth studies focused on BDMs with a longer mulching period must be developed to promote the substitution of BDMs into PE to reduce the residual mulch pollution in cotton fields.
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This study aimed to develop an effective technique for extracting total anthocyanins from purple sweet potato (Mianzishu 9) (PSP9) by ultrasound-assisted compound enzymatic extraction (UAEE). Single-factor experiments, Plackett-Burman experimental design, and response surface methodology were utilized for optimizing extraction conditions, and the antioxidant activities were evaluated. Anthocyanins were also measured using an ultra-performance liquid chromatograph linked to a mass spectrometer (UPLC-MS). The maximum yield of total anthocyanins was 2.27 mg/g under the following conditions: the ethanol concentration was 78%, the material-to-liquid ratio was 1:15 g/mL, the enzyme ratio (cellulase: pectinase: papain) was 2:2:1 and its hydrolysis was at 41 °C, pH = 4.5, 1.5 h, the ultrasonication was at 48 °C and conducted twice for 20 min each time. In addition to higher yield, anthocyanins extracted from purple sweet potato by UAEE showed great ability to scavenge DPPH (IC50 of 0.089 µg/mL) and hydroxyl radicals (IC50 of 100.229 µg/mL). Five anthocyanins were found in the purple sweet potato extract from UAEE. Taken together, the ultrasound-assisted compound enzymatic method can rapidly and effectively extract anthocyanins with greater antioxidant capacity from purple sweet potato.
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Ipomoea batatas , Antocianinas/química , Antioxidantes/farmacologia , Cromatografia Líquida , Ipomoea batatas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espectrometria de Massas em Tandem , TecnologiaRESUMO
Listeria monocytogenes (L. monocytogenes) is one of the most lethal pathogenic bacteria. Although the traditional microbial culture method has high sensitivity and selectivity for the diagnosis of L. monocytogenes, it is time-consuming and not suitable for on-site detection. A rapid, convenient and visualized on-site detection method is particularly needed. In this work, Fe3O4@UiO-66-NH2 was prepared for both magnetic separation and lateral flow immunoassay (LFIA) for the detection of L. monocytogenes by taking advantage of the easy separation of the magnetic core Fe3O4 and the high surface area of the outer layer UiO-66-NH2. Fe3O4@UiO-66-NH2 with a high surface area and good water-dispersibility and optical properties was synthesized by a simple hydrothermal process. It could directly adsorb on the surface of target bacteria and form Fe3O4@UiO-66-NH2-bacteria conjugates, without the labeling of an antibody. After magnetic separation and concentration, the Fe3O4@UiO-66-NH2-bacteria conjugates were detected by the antibody on the test line of the LFIA strip, resulting in a visible orange band. The capture efficiency and LFIA detection of Fe3O4@UiO-66-NH2 were optimized in this study. Under the optimal conditions, a good linear correlation between the test line intensity and the concentration of L. monocytogenes was obtained in the range of 105-108 CFU mL-1, and the limit of detection was 2.2 × 106 CFU mL-1 by the naked eye. The Fe3O4@UiO-66-NH2-based LFIA strip showed strong specificity for L. monocytogenes, and the detection took 45 min without culture enrichment. Therefore, the proposed Fe3O4@UiO-66-NH2-based strip showed the advantages of simple synthesis, being label-free, low cost, good selectivity and convenience.
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Listeria monocytogenes , Nanocompostos , Imunoensaio/métodos , Fenômenos Magnéticos , Estruturas Metalorgânicas , Ácidos FtálicosRESUMO
Listeria monocytogenes is one of the major foodborne pathogens, which may cause serious food safety problems and illnesses in humans and animals. Consequently, sensitive, fast and reliable detection methods, as well as effective sample preparation methods are in great demand. In this study, a magnetic separation method based on a aptamer functionalized positively-charged magnetic beads (Fe3O4@aptamer) was established and a fluorescent test strip sensor was constructed for the rapid, sensitive and specific detection of Listeria monocytogenes. Benefiting from the dual recognition and signal amplification process of Fe3O4@aptamer enrichment and the polymerase chain reaction of the hly gene, the fluorescent strip sensor for the detection of Listeria monocytogenes was determined to be reliable and sensitive, with a linear curve obtained in the range of 1.0 × 102 to 1.9 × 108 CFU mL-1, and a detection limit of 1.0 × 102 CFU mL-1. The detection was achieved in 3 h without culture enrichment. Furthermore, the developed method was successfully applied for the detection of Listeria monocytogenes in pork tenderloin, with the recoveries ranging from 91.1% to 97.1%, and a coefficient of variation of less than 23.4%, revealing the feasible and reliable application of this method in practical samples. The proposed fluorescent strip sensor is rapid, sensitive and specific, giving it great application prospects for use in the field of pathogenic bacterium detection.
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Listeria monocytogenes , Animais , Microbiologia de Alimentos , Separação Imunomagnética/métodos , Listeria monocytogenes/genética , Fenômenos Magnéticos , Reação em Cadeia da PolimeraseRESUMO
Poly-(butylene adipate-co-terephthalate) (PBAT) has become one of the most prevalent biodegradable plastic film materials owing to its good degradability, mechanical properties, and processability. However, the degradation time of this material was too fast and the functional period was short, which limited its application. Herein, three new tropolone-based UV absorbers (UVA-1C, UVA-4C and UVA-6C) were rationally designed and blended into PBAT. The PBAT/UVA films that formed were used against UV aging and prolonged the functional period of PBAT film. The three new absorbers were synthesized by bridging two tropolones using three different organic chains with different flexibility. Among them, the UVA-6C showed the strongest UV absorbance at around 238 nm and 320 nm. Consequently, the PBAT/UVA-6C film showed an extended validity period of 240 h in the Xenon lamp aging machine and a prolonged functional period of 8 d during the field application test when compared to pure PBAT. More importantly, a 7.8% increase in the maize yield was obtained under PBAT/UVA-6C film relative to pure PBAT film. Obviously, the novel prepared UVA-6C compound is a good candidate for UV absorption in PBAT, which makes PBAT/UVA-6C film more advantageous over pure PBAT in practical applications as biodegradable agricultural film.
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As new fluorescent materials, light wavelength conversion materials (light conversion agents) have attracted increasing attention from scientific researchers and agricultural materials companies due to their potential advantages in efficiently utilizing solar energy and increasing crop yield. According to the material properties, the light conversion agents can be divided into fluorescent dyes, organic rare-earth complexes, and inorganic rare-earth complexes. The current researches indicates that the fluorescent dyes have relatively high production costs, poor light stability, difficult degradation processes, and easily cause pollution to the ecological environment. The organic rare-earth complexes have short luminescence times, high production costs, and suffer from rapid decreases in luminescence intensity. Compared with fluorescent dyes and organic rare-earth complexes, although rare-earth inorganic complexes have high luminous efficiency, stable chemical properties, and better spectral matching performance, the existing inorganic light conversion agents have relatively poor dispersibility in agricultural films. According to the research on light conversion agents at home and abroad in recent years, this paper first introduces the three common light conversion agents, namely fluorescent dyes, organic rare-earth complexes, and inorganic rare-earth complexes, as well as their uses in agricultural films and their mechanisms of light conversion. At the same time, the preparation methods, advantages, disadvantages, and existing problems of various light conversion agents are classified and explained. Finally, we predict the development trends for light conversion agents in the future by considering six aspects, namely efficiency, cost, compatibility with greenhouse films, light matching, and light transmittance, in order to provide a reference for the preparation of stable and efficient light conversion agent materials.
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An iatrogenic pseudoaneurysm of the radial artery and spontaneous venous malformation are associated with median nerve compression. However, the superficial brachial artery (SBA) has rarely been described as the cause of neurological deficits due to median nerve compression. A 61-year-old man was admitted to our clinic with a 1-year history of intermittent aching palsy in the left thumb that had progressed to the first three fingers. Clinical examination revealed mild sensory disturbance and hyperpathia in the first three fingers and weakness of the opponens pollicis. Ultrasound and magnetic resonance imaging confirmed that the SBA was compressing the median nerve by almost one-third. When anomalies of the SBA impinge on the median nerve, pulsatile pressure is applied to the nerve trunk. This may trigger ectopic stimulation of sensory fibers, leading to severe pain, sensory neuropathy, and motor disturbance. Considering the substantial difficulties and risks of a surgical operation as well as the patient's wish to undergo conservative treatment, we performed muscle relaxation and acupuncture to relieve the pressure of the surrounding soft tissue and in turn decrease the impingement of the SBA on the median nerve. A satisfactory treatment effect was reached in this case.