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Due to its exceptional advantages, such as high specific strength, high specific modulus, and good fatigue resistance, carbon-fiber-reinforced plastic (CFRP) is frequently utilized in aerospace, aviation, automotive, rail transportation, and other areas. Composite components typically need to be joined and integrated. In the equipment manufacturing industry, the most used methods for processing composite components are cutting, drilling, and surface treatment. The quality of CFRP is significantly impacted by traditional mechanical processing, causing flaws like delamination, burrs, and tears. Laser processing technology has emerged as a crucial method for processing CFRP for its high quality, non-contact, simple control, and automation features. The most recent research on the laser processing of CFRP is presented in this paper, supporting scientists and engineers who work in the field in using this unconventional manufacturing technique. This paper gives a general overview of the key features of laser processing technology and the numerous machining techniques available. The concepts and benefits of laser processing technology are discussed in terms of the material properties, mode of operation, and laser characteristics, as well as the methods to achieve high efficiency, low damage, and high precision. This paper reviews the research development of laser processing of carbon-fiber-reinforced plastics, and a summary of the factors affecting the quality of CFRP laser processing. Therefore, the research content of this article can be used as a theoretical basis for reducing thermal damage and improving the processing quality of laser-processed composite materials, while, on this basis, we analyze the development trend of CFRP laser processing technology.
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Near-infrared (NIR) light-triggered photoredox catalysis is highly desirable because NIR light occupies almost 50% of solar energy and possesses excellent penetrating power in various media. Herein we utilize a metal-free boron dipyrromethene (BODIPY) derivative as the photocatalyst to achieve NIR light (720 nm LED)-driven oxidation of benzylamine derivatives, sulfides, and aryl boronic acids. Compared to blue light-driven photooxidation using Ru(bpy)3Cl2 as a photocatalyst, NIR light-driven photooxidation exhibited solvent independence and superior performance in large-volume (20 mL) reaction, presumably thanks to the neutral structure of a BODIPY photocatalyst and the deeper penetration depth of NIR light. We further demonstrate the application of this metal-free NIR photooxidation to prodrug activation and combination with Cu-catalysis for cross coupling reaction, exhibiting the potential of metal-free NIR photooxidation as a toolbox for organic synthesis and drug development.
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Raios Infravermelhos , Luz , Ácidos Borônicos , Catálise , Oxirredução , SulfetosRESUMO
Organic self-assembled co-crystals have garnered considerable attention due to their facile synthesis and intriguing properties, but supramolecular interactions restrict their stability in aqueous solution, which is especially important for biological applications. Herein, we report on the first biological application of aqueous dispersible self-assembled organic co-crystals via the construction of metal-organic framework (MOF) -stabilized co-crystals. In particular, we built an electron-deficient MOF with naphthalene diimide (NDI) as the ligand and biocompatible Ca2+ as the metal nodes. An electron donor molecule, pyrene, was encapsulated to form the host-guest MOF self-assembled co-crystal. We observed that such MOF structure leads to uniquely high-density ordered arrangement and the close intermolecular distance (3.47â Å) of the charge transfer pairs. Hence, the concomitant superior charge transfer interaction between pyrene/NDI can be attained and the resultant photothermal conversion efficiency of Py@Ca-NDI in aqueous solution can thus reach up to 41.8 %, which, to the best of our knowledge, is the highest value among the reported organic co-crystal materials; it is also much higher than that of the FDA approved photothermal agent ICG as well as most of the reported MOFs. Based on this realization, as a proof of concept, we demonstrated that such a self-assembled organic co-crystal platform can be used in biological applications that are exemplified via highly effective long wavelength light photothermal therapy.
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Materiais Biocompatíveis/química , Cálcio/química , Imidas/química , Estruturas Metalorgânicas/síntese química , Naftalenos/química , Fototerapia , Pirenos/química , Catálise , Estruturas Metalorgânicas/químicaRESUMO
A method for the identification and quantification of bisphenol A and 12 bisphenol analogues in river water and sediment samples combining liquid-liquid extraction, precolumn derivatization, and ultra high-performance liquid chromatography coupled with tandem mass spectrometry was developed and validated. Analytes were extracted from the river water sample using a liquid-liquid extraction method. Dansyl chloride was selected as a derivatization reagent. Derivatization reaction conditions affecting production of the dansyl derivatives were tested and optimized. All the derivatized target compounds were well separated and eluted in 10 min. Dansyl chloride labeled compounds were analyzed using a high-resolution mass spectrometer with electrospray ionization in the positive mode, and the results were confirmed and quantified in the parallel reaction monitoring mode. The method validation results showed a satisfactory level of sensitivity. Linearity was assessed using matrix-matched standard calibration, and good correlation coefficients were obtained. The limits of quantification for the analytes ranged from 0.005 to 0.02 ng/mL in river water and from 0.15 to 0.80 ng/g in sediment. Good reproducibility of the method in terms of intra- and interday precision was achieved, yielding relative standard deviations of less than 10.1 and 11.6%, respectively. Finally, this method was successfully applied to the analysis of real samples.
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OBJECTIVE: The objective of this study is to evaluate our 10-year clinical experience in surgical management of patients with osteoradionecrosis (ORN) unresolved with conservative nonoperative treatment. PATIENTS AND METHODS: The medical records of 120 patients who had been surgically treated for ORN during a 10-year period (January 2003 to January 2013) were retrospectively reviewed. RESULTS: The most predilection ORN site was mandible (82.5%), followed by the maxilla (11.7%). ORN developed within initial 12 months in 39.2% and within the first 3 years in 68.3%. The median radiation dose was 68.1 Gy (range, 35-148 Gy), but 51 patients (42.5%) experienced ORN even though radiation doses were controlled under 60 Gy. Surgical trauma, as we believed, was the most important factor leading to this result. Among all the patients, 12 (10.0%) patients were found ineligible for operative treatment due to comorbid systematic diseases whereas none healed or improved. In terms of surgical management of the rest of the 108 patients, 90 (75.0%) patients underwent radical resection (4 patients unhealed), and 18 (15.0%) patients underwent mild surgical procedures such as sequestrectomy or debridement (1 patient unhealed). Of the 90 radical resection patients, 58 patients underwent radical resections and immediate microvascular flap reconstruction (19 bone flaps and 39 soft flaps), and 32 patients only experience radical resection (5 patients received second-stage reconstruction). According to follow-up information, 55 patients were free of disease. CONCLUSION: Though priority should be given to surgical treatment for the patient whose ORN does not respond to conservative nonoperative treatment, we may as well take into account more individualized regimens based on ORN severity. A hard lesson learned from our article is that the oral maxillofacial surgeon should minimize the trauma for jaws as possible as he can, especially to patients who need to receive postoperative radiotherapy.
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Doenças Mandibulares/cirurgia , Doenças Maxilares/cirurgia , Osteorradionecrose/cirurgia , Adulto , Idoso , Transplante Ósseo/métodos , Carcinoma de Células Escamosas/radioterapia , Desbridamento/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/radioterapia , Terapia Neoadjuvante , Neoplasias Faríngeas/radioterapia , Dosagem Radioterapêutica , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Retalhos Cirúrgicos/transplanteRESUMO
Due to the significant POPs characteristics, dioxins caused concern in public health and environmental protection. Evaluating the toxicity risk of dioxin degradation pathways is critical. OCDD, 1,2,3,4,6,7,8-HpCDD, and 1,2,3,4,6,7,8-HpCDF, which are highly abundant in the environment and have strong biodegradation capabilities, were selected as precursor molecules in this study. Firstly, their transformation pathways were deduced during the metabolism of biometabolism, microbial aerobic, microbial anaerobic, and photodegradation pathways, and density function theory (DFT) was used to calculate the Gibbs free energy to infer the possibility of the occurrence of the transformation pathway. Secondly, the carcinogenic potential of the precursors and their degradation products was evaluated using the TOPKAT modeling method. With the help of the positive indicator (0-1) normalization method and heat map analysis, a significant increase in the toxic effect of some of the transformation products was found, and it was inferred that it was related to the structure of the transformation products. Meanwhile, the strength of the endocrine disrupting effect of dioxin transformation products was quantitatively assessed using molecular docking and subjective assignment methods, and it was found that dioxin transformation products with a higher content of chlorine atoms and molecules similar to those of thyroid hormones exhibited a higher risk of endocrine disruption. Finally, the environmental health risks caused by each degradation pathway were comprehensively assessed with the help of the negative indicator (1-2) standardization method, which provides a theoretical basis for avoiding the toxicity risks caused by dioxin degradation transformation. In addition, the 3D-QSAR model was used to verify the necessity and rationality of this study. This paper provides theoretical support and reference significance for the toxicity assessment of dioxin degradation by-products from inferred degradation pathways.
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Biodegradação Ambiental , Dioxinas , Dioxinas/toxicidade , Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidadeRESUMO
Salicylic esters (SEs), the widely used ultraviolet (UV) absorbers in sunscreen products, have been found to have health risks such as skin sensitization and estrogenic effects. This study aims to design SE substitutes that maintain high UV absorbance while reducing estrogenicity. Using molecular docking and Gaussian09 software for initial assessments and further application of a combination of two-dimensional and three-dimensional quantitative structure-activity relationships (2D-QSAR and 3D-QSAR, respectively) models, we designed 73 substitutes. The best-performing molecules, ethylhexyl salicylate (EHS)-5 and EHS-15, significantly reduced estrogenicity (44.54 % and 17.60 %, respectively) and enhanced UV absorbance (249.56 % and 46.94 %, respectively). Through screening for human health risks, we found that EHS-5 and EHS-15 were free from skin sensitivity and eye irritation and exhibited reduced skin permeability compared with EHS. Furthermore, the photolysis and synthetic pathways of EHS-5 and EHS-15 were deduced, demonstrating their good photodegradability and potential synthesizability. In addition, we analyzed the mechanisms underlying the changes in estrogenic effects and UV absorption properties. We identified covalent hydrogen bond basicity and acidity Propgen value for atomic molecular properties and the highest occupied molecular orbital eigenvalue as the main factors affecting the estrogenic effect and UV absorbance of SEs, respectively. This study focuses on the design and screening of SEs, exhibiting enhanced functionality, reduced health risks, and synthetic feasibility.
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Estrogênios , Simulação de Acoplamento Molecular , Relação Quantitativa Estrutura-Atividade , Salicilatos , Protetores Solares , Protetores Solares/química , Protetores Solares/toxicidade , Salicilatos/química , Salicilatos/toxicidade , Estrogênios/química , Estrogênios/toxicidade , Humanos , Raios Ultravioleta , Fotólise , Animais , Pele/efeitos dos fármacos , Pele/efeitos da radiaçãoRESUMO
The degradation of fluoroquinolones (FQs) via advanced oxidation processes (AOPs) is a promising avenue, yet the complete mineralization of certain FQ molecules remains elusive, raising concerns about the formation of toxic by-products. This study delineates five primary AOP degradation pathways for 16 commercially available FQ molecules, inferred from existing literature. Density functional theory (DFT) was employed to calculate the bond dissociation energies within these pathways to elucidate the correlation between bond strength and molecular architecture. Subsequently, Comparative Molecular Similarity Index Analysis (CoMSIA) models were constructed for various degradation reactions, including piperazine ring cleavage, defluorination, hydroxylation, and piperazine ring hydroxylation. Three-dimensional contour maps generated from these models provide a deeper understanding of the interplay between FQ molecular structure and bond dissociation energy. Furthermore, toxicity predictions for 16 FQ molecules and their advanced oxidation intermediates, conducted using VEGA 1.2.3 software, indicate that degradation products from pathways P2 and P5 pose a heightened health risk relative to their parent compounds. Furthermore, the application of the Multwfn program to compute the Fukui function for FQ molecules discerns the disparity in degradation propensities, highlighting that N atoms with higher f0 values can augment the likelihood of piperazine ring cleavage. HOMO-LUMO distribution diagrams further confirm that methoxy substitution at the 1-position leads to a dilution of HOMOs on the piperazine ring and an increased energy gap for free radical reactions, diminishing the reactivity with hydroxyl radicals. This study elucidates the pivotal role of structural characteristics in FQ antibiotics for their degradation efficiency within AOPs and unveils the underlying mechanisms of bond dissociation energy disparities. The toxicity parameter predictions for FQ molecules and their intermediates offer unique perspectives and theoretical underpinnings for mitigating the use of high-risk FQs and for devising targeted degradation strategies to circumvent the generation of toxic intermediates in AOPs through molecular structure optimization.
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Objective: To investigate the effectiveness of HoloSight Orthopaedic Trauma Surgery Robot-assisted infra-acetabular screw placement for treatment of acetabular fractures. Methods: The clinical data of 23 patients with acetabular fractures treated with open reduction and internal fixation and infra-acetabular screw placement in two medical centers between June 2022 and October 2023 were retrospectively analyzed. According to the the method of infra-acetabular screw placement, the patients were divided into navigation group (10 cases, using HoloSight Orthopaedic Trauma Surgery Robot-assisted screw placement) and freehand group (13 cases, using traditional X-ray fluoroscopy to guide screw placement). There was no significant difference in gender, age, body mass index, cause of injury, time from injury to operation, and Judet-Letournel classification between the two groups ( P>0.05). The time of infra-acetabular screw placement, the fluoroscopy frequency, the guide pin adjustment times, the quality of screw placement, the quality of fracture reduction, and the function of hip joint were compared between the two groups. Results: All patients completed the operation successfully. The time of screw placement, the fluoroscopy frequency, and guide pin adjustment times in the navigation group were significantly less than those in the freehand group ( P<0.05). The quality of screw placement in the navigation group was significantly better than that in the freehand group ( P<0.05). Patients in both groups were followed up 6-11 months, with an average of 7.7 months. There were 9 and 9 cases in the navigation group and the freehand group who achieved excellent and good fracture reduction quality at 1 week after operation, and 12 and 12 cases with excellent and good hip joint function at last follow-up, respectively, and there was no significant difference between the two groups ( P>0.05). The fractures in both groups healed well, and there was no significant difference in healing time ( P>0.05). During the follow-up, there was no complication related to screw placement, such as failure of internal fixation, vascular and nerve injury, incisional hernia. Conclusion: In the treatment of acetabular fractures, compared with the traditional freehand screw placement, the HoloSight Orthopaedic Trauma Surgery Robot-assisted screw placement can reduce the time of screw placement, improve the accuracy of screw placement, and reduce the amount of radiation, which is an efficient, accurate, and safe surgical method.
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Acetábulo , Parafusos Ósseos , Fixação Interna de Fraturas , Fraturas Ósseas , Procedimentos Cirúrgicos Robóticos , Humanos , Acetábulo/lesões , Acetábulo/cirurgia , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Estudos Retrospectivos , Fraturas Ósseas/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Fluoroscopia , Resultado do Tratamento , Cirurgia Assistida por Computador/métodos , Masculino , Feminino , Adulto , Cirurgia de Cuidados CríticosRESUMO
Foodborne illness caused by Salmonella spp. is one of the most prevalent public health problems globally, which have brought immeasurable economic burden and social impact to countries around the world. Neither current nucleic acid amplification detection method nor standard culture method (2-3 days) are suitable for field detection in areas with a heavy burden of Salmonella spp. Here, we developed a highly sensitive and accurate assay for Salmonella spp. detection in less than 40 min. Specifically, the invA gene of Salmonella spp. was amplified by recombinase polymerase amplification (RPA), followed by Pyrococcus furiosus Argonaute (PfAgo)-based target sequence cleavage, which could be observed by a fluorescence reader or the naked eye. The assay offered the lowest detectable concentration of 1.05 × 101 colony forming units/mL (CFU/mL). This assay had strong specificity and high sensitivity for the detection of Salmonella spp. in field samples, which indicated the feasibility of this assay.
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Microbiologia de Alimentos , Técnicas de Amplificação de Ácido Nucleico , Pyrococcus furiosus , Salmonella , Pyrococcus furiosus/genética , Salmonella/genética , Salmonella/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Inocuidade dos Alimentos , Recombinases/metabolismo , Recombinases/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Sensibilidade e Especificidade , Contaminação de Alimentos/análiseRESUMO
Organophosphorus pesticides (OPs) are widely used in agricultural production, but the resulting pollution and drug resistance have sparked widespread concern. Therefore, this paper built a model to design OP substitute molecules with high functionality and environmental friendliness, as well as conducted various human health and ecological environment evaluations, synthetic accessibility screening, and easy detection screening. The functionality of the two OP substitute molecules, DIM-100 and DIM-164, increased by 22.79 % and 22.18 %, respectively, and the environmental friendliness increased by 18.07 % and 24.02 %, respectively. The human health risk and ecological, environmental risks were significantly reduced. Both molecules are easy to synthesize, and their detection sensitivity is 9.85 % and 11.24 % higher than that of the target molecule, respectively. Furthermore, significant changes in the distribution of electrons and holes near the C8 and S1 atoms of the OP substitute molecule resulted in easier breakage of the C8-S1 bond, enhancing its photodegradation ability. The charge transfer ability between the atoms of the molecule (as increasing the electron-withdrawing group led to an increase in charge of the P atom) and the volume of the cholinesterase active pocket both affect the functionality of the DIM substitute molecule. That is, the volume of the cholinesterase active pocket of the bee is smaller than that of the brown planthopper and is more affected by the volume of the OP molecule. Furthermore, the mutual verification analysis of the bidirectional selectivity effect of OP substitute molecules between the BayesianRidge model and the 3D-QS(A2 + ∀3)R model reveals that the overall charge transfer degree of DIM substitute molecules is the main reason for the increase in the bidirectional selectivity effect.
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Praguicidas , Humanos , Animais , Praguicidas/análise , Compostos Organofosforados/análise , Agricultura , Colinesterases , Poluição Ambiental/análiseRESUMO
Rationally designing highly active oxygen evolution reaction (OER) electrocatalysts with robust stability is critical for industrial electrochemical water splitting. Hierarchical iron-nickel oxyhydroxide nanosheets directly grown on porous TiFe2-based intermetallics are designed and prepared as OER catalysts. The best-performing nanosheets only need 295 mV to achieve 100 mA cm-2, along with exceptional durability at a high current density of 1000 mA cm-2. This work introduces a scalable strategy for producing robust OER catalysts that have potential for industrial applications.
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The incidence of hyponatremia after spinal cord injury was reported to be between 25 and 80%. Hyponatremia can lead to a variety of clinical symptoms, from mild to severe and even life-threatening. Hyponatremia is often associated with diabetes insipidus, which refers to insufficient arginine vasopressin (AVP) secretion or defective renal response to AVP, with clinical manifestations of syndromes such as hypoosmolality, polydipsia, and polydipsia. Recent mechanistic studies on hyponatremia and diabetes insipidus after acute spinal cord injury have been performed in isolation, without integrating the above two symptoms into different pathological manifestations that occur in the same injury state and without considering the acute spinal cord injury patient's condition as a whole. The therapeutic principles of CSWS and SIADH are in opposition to one another. It is not easy to identify the mechanism of hyponatremia in clinical practice, which makes selecting the treatment difficult. According to the existing theories, treatments for hyponatremia and diabetes insipidus together are contraindicated, whether the mechanism of hyponatremia is thought to be CSWS or SIADH. In this paper, we review the mechanism of these two pathological manifestations and suggest that our current understanding of the mechanisms of hyponatremia and diabetes insipidus after high acute cervical SCI is insufficient, and it is likely that there are other undetected pathogenetic mechanisms.
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Aromatic amines, one of the most widely used low-cost antioxidants in rubbers, have been regarded as pollutants with human health concerns. To overcome this problem, this study developed a systematic molecular design, screening, and performance evaluation method to design functionally improved, environmentally friendly and synthesizable aromatic amine alternatives for the first time. Nine of 33 designed aromatic amine derivatives have improved antioxidant property (lower bond dissociation energy of N-H), and their environmental and bladder carcinogenicity impacts were evaluated through toxicokinetic model and molecular dynamics simulation. The environmental fate of the designed AAs-11-8, AAs-11-16, and AAs-12-2 after antioxidation (i.e., peroxyl radicals (ROO·), hydroxyl radicals (HO·), superoxide anion radicals (O2·-) and ozonation reaction) was also analyzed. Results showed that the by-products of AAs-11-8 and AAs-12-2 have less toxicity after antioxidation. In addition, human bladder carcinogenicity of the screened alternatives was also evaluated through adverse outcome pathway. The carcinogenic mechanisms were analyzed and verified through amino acid residue distribution characteristics, 3D-QSAR and 2D-QSAR models. AAs-12-2, with high antioxidation property, low environmental impacts and carcinogenicity, was screened as the optimum alternative for 3,5-Dimethylbenzenamine. This study provided theoretical support for designing environmentally friendly and functionally improved aromatic amine alternatives from toxicity evaluation and mechanism analysis.
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Rotas de Resultados Adversos , Carcinógenos , Humanos , Carcinógenos/toxicidade , Carcinógenos/química , Toxicocinética , Aminas/toxicidade , Aminas/química , Radical HidroxilaRESUMO
Objective: To investigate the early effectiveness of transiliac-transsacral screws internal fixation assisted by augmented reality navigation system HoloSight (hereinafter referred to as "computer navigation system") in the treatment of posterior pelvic ring injuries. Methods: A retrospective analysis was made in the 41 patients with posterior pelvic ring injuries who had been treated surgically with transiliac-transsacral screws between June 2022 and June 2023. The patients were divided into navigation group (18 cases, using computer navigation system to assist screw implantation) and freehand group (23 cases, using C-arm X-ray fluoroscopy to guide screw implantation) according to the different methods of transiliac-transsacral screws placement. There was no significant difference in gender, age, body mass index, causes of injuries, Tile classification of pelvic fracture, days from injury to operation, usage of unlocking closed reduction technique between the two groups ( P>0.05). The time of screw implantation, the fluoroscopy times, the guide wire adjustment times of each screw, and the incidence of complications were recorded and compared between the two groups. The position of the transiliac-transsacral screw was scanned by CT within 2 days after operation, and the position of the screw was classified according to Gras standard. Results: The operation was successfully completed in both groups. The time of screw implantation, the fluoroscopy times, and the guide wire adjustment times of each screw in the navigation group were significantly less than those in the freehand group ( P<0.05). There were 2 cases of incision infection in the freehand group, and the incision healed by first intention after active dressing change; there was no screw-related complication in the navigation group during operation and early period after operation; the difference in incidence of complications between the two groups (8.7% vs. 0) was not significant ( P=0.495). According to the Gras standard, the screw position of the navigation group was significantly better than that of the freehand group ( P<0.05). Conclusion: Compared with the traditional freehand method, the computer navigation system assisted transiliac-transsacral screws internal fixation in the treatment of posterior pelvic ring injuries has advantages of improving the accuracy of screw implantation and reducing radiation damage and the time of screw implantation.
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Reimplante , Infecção da Ferida Cirúrgica , Humanos , Estudos Retrospectivos , Índice de Massa CorporalRESUMO
In recent years, meat adulteration safety incidents have occurred frequently, triggering widespread attention and discussion. Although there are a variety of meat quality identification methods, conventional assays require high standards for personnel and experimental conditions and are not suitable for on-site testing. Therefore, there is an urgent need for a rapid, sensitive, high specificity and high sensitivity on-site meat detection method. This study is the first to apply RPA combined with CRISPR/Cas12a technology to the field of multiple meat identification. The system developed by parameter optimization can achieve specific detection of chicken, duck, beef, pork and lamb with a minimum target sequence copy number as low as 1 × 100 copies/µL for 60 min at a constant temperature. LFD test results can be directly observed with the naked eye, with the characteristics of fast, portable and simple operation, which is extremely in line with current needs. In conclusion, the meat identification RPA-CRISPR/Cas12a-LFD system established in this study has shown promising applications in the field of meat detection, with a profound impact on meat quality, and provides a model for other food safety control programs.
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The ability to deliver electrons is vital for dye-based photocatalysts. Conventionally, the aromatic stacking-based charge-transfer complex increases photogenerated electron accessibility but decreases the energy of excited-state dyes. To circumvent this dilemma, here we show a strategy by tuning the stacking mode of dyes. By decorating naphthalene diimide with S-bearing branches, the S···S contact-linked naphthalene diimide string is created in coordination polymer, thereby enhancing electron mobility while simultaneously preserving competent excited-state reducing power. This benefit, along with in situ assembly between naphthalene diimide strings and exogenous reagent/reactant, improves the accessibility of short-lived excited states during consecutive photon excitation, resulting in greater efficiency in photoinduced electron-transfer activation of inert bonds in comparison to other coordination polymers with different dye-stacking modes. This heterogeneous approach is successfully applied in the photoreduction of inert aryl halides and the successive formation of CAr-C/S/P/B bonds with potential pharmaceutical applications.
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Calcogênios , Compostos Inorgânicos , Polímeros/química , Transporte de Elétrons , Naftalenos/químicaRESUMO
Anthraquinone (AQ) as an effective hydrogen atom transfer catalyst was limited in photocatalysis application due to the dimerization of reduced AQ. Sr-NDI@AQ, encapsulating AQ into the channel of Sr-NDI, paved a new way for solving the problem of dimerization of reduced AQ and improving the catalytic efficiency owing to the fast electron transfer from reduced AQ to the ligand through host-guest interaction. The structure of Sr-NDI@AQ was determined by single-crystal X-ray diffraction, and the value for distance and torsion angle between the ligand and AQ was calculated. The photochemical and electrochemical properties for Sr-NDI@AQ were characterized through a series of experiments. The coupling reaction between aldehyde and phenyl vinyl sulfone and photoacetalization reaction were carried out, displaying the improving catalytic efficiency of Sr-NDI@AQ compared to Sr-NDI and AQ. The reaction mechanisms were proposed through radical capture and electron paramagnetic resonance experiments.
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Electrochemical water splitting offers an appealing method to produce hydrogen as we attempt to achieve global carbon neutrality. However, the lack of earth-abundant, low-cost, active, and stable catalysts at large current densities severely hinders its industrial applications. TiNi3-based intermetallics as porous monolith catalysts (PMCs) exhibit an efficient hydrogen evolution reaction (HER) performance (an overpotential of 244 mV to afford 200 mA cm-2) and excellent stability in 1 M KOH. Theoretical calculations demonstrate that the synergetic effect between Ni and Mo can enhance HER activity. PMCs provide a new strategy to design catalysts with efficient and stable performance for industrial applications.
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Here, we show that a reactive synthesis method of mixed elemental powders can be used to synthesize a porous electrode consisting of an intermetallic Fe5Si3 that exhibits catalytic activity towards oxygen evolution reaction (OER) in acidic solutions, which is capable of delivering 10 mA cm-2 at an overpotential of 0.73 V and a small Tafel slope of ~ 381.8 mV dec-1. The amorphous silica formed in the anode surface during the electrochemical process is multifunctional, as it protects the electrode substrate from corrosion and acts as electrocatalysts for OER. Remarkably, the Si-based intermetallics can be generalized to include other OER catalytic elements (Mn, Fe, Co), including Mn-Si and Co-Si intermetallics.