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Nonlinear optical (NLO) coherent light sources are widely applied in many areas of science and technology. As the core medium, the NLO material is required to have a wide transparent range, a large NLO response, and a high laser damaged threshold (LDT). It is common knowledge that langasite (La3Ga5SiO14, LGS) crystal has an underdeveloped second-harmonic generation (SHG) coefficient and a small birefringence, which seriously restrict its application in the NLO field, despite that it has a broad transmittance spectrum and a moderate LDT. Herein, we have successfully obtained novel langasite NLO crystals LGSS (La3Ga5Si0.5Sn0.5O14) and LGGS (La3Ga5Ge0.5Sn0.5O14), with short UV absorption edges of 209 and 212 nm, respectively. Incorporating heavy ions Sn4+ into the structure, a distorted BO6 octahedron was adjusted by the radius difference between Sn4+ and Si4+/Ge4+, which caused the strong SHG responses in LGSS (â¼10.77 × KDP) and LGGS (â¼9.23 × KDP) and increased birefringences of 0.034 and 0.025, respectively. Besides, they also had large energy band gaps (4.95 eV for LGSS, and 4.93 eV for LGGS), which allowed high LDTs with LGSS of 1.3 GW/cm2 and LGGS of 813 MW/cm2. This work demonstrates a new strategy to enhance SHG responses and birefringence for existing NLO materials and enriches langasite family crystals.
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BACKGROUND: Glucagon-like peptide-1 (GLP-1) (7-36) amide, an endogenous active form of GLP-1, has been shown to modulate oxidative stress and neuronal cell survival in various neurological diseases. OBJECTIVE: This study investigated the potential effects of GLP-1(7-36) on oxidative stress and apoptosis in neuronal cells following traumatic brain injury (TBI) and explored the underlying mechanisms. METHODS: Traumatic brain injury (TBI) models were established in male SD rats for in vivo experiments. The extent of cerebral oedema was assessed using wet-to-dry weight ratios following GLP-1(7-36) intervention. Neurological dysfunction and cognitive impairment were evaluated through behavioural experiments. Histopathological changes in the brain were observed using haematoxylin and eosin staining. Oxidative stress levels in hippocampal tissues were measured. TUNEL staining and Western blotting were employed to examine cell apoptosis. In vitro experiments evaluated the extent of oxidative stress and neural apoptosis following ERK5 phosphorylation activation. Immunofluorescence colocalization of p-ERK5 and NeuN was analysed using immunofluorescence cytochemistry. RESULTS: Rats with TBI exhibited neurological deterioration, increased oxidative stress, and enhanced apoptosis, which were ameliorated by GLP-1(7-36) treatment. Notably, GLP-1(7-36) induced ERK5 phosphorylation in TBI rats. However, upon ERK5 inhibition, oxidative stress and neuronal apoptosis levels were elevated, even in the presence of GLP-1(7-36). CONCLUSION: In summary, this study suggested that GLP-1(7-36) suppressed oxidative damage and neuronal apoptosis after TBI by activating ERK5/CREB.
Asunto(s)
Lesiones Traumáticas del Encéfalo , Péptido 1 Similar al Glucagón , Fármacos Neuroprotectores , Animales , Masculino , Ratas , Apoptosis , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Modelos Animales de Enfermedad , Péptido 1 Similar al Glucagón/farmacología , Péptido 1 Similar al Glucagón/uso terapéutico , Hipocampo , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo , Ratas Sprague-Dawley , Fragmentos de Péptidos/farmacología , Fragmentos de Péptidos/uso terapéutico , Proteína Quinasa 7 Activada por Mitógenos/efectos de los fármacos , Proteína Quinasa 7 Activada por Mitógenos/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismoRESUMEN
A PhI(OAc)2/Pd(OAc)2 system that synergistically promotes the formation of 8-hydroxyquinoline derivatives from benzoxazoles and alcohols has been developed. The reaction proceeded smoothly with a range of benzoxazoles and alcohols to give the corresponding 8-hydroxyquinoline derivatives in moderate yields.
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Small public spaces are the key built environment elements that provide venues for various of activities. However, existing measurements or approaches could not efficiently and effectively quantify how small public spaces are being used. In this paper, we utilized a deep convolutional neural network to quantify the usage of small public spaces through recorded videos as a reliable and robust method to bridge the literature gap. To start with, we deployed photographic devices to record videos that cover the minimum enclosing square of a small public space for a certain period of time, then utilized a deep convolutional neural network to detect people in these videos and converted their location from image-based position to real-world projected coordinates. To validate the accuracy and robustness of the method, we experimented our approach in a residential community in Beijing, and our results confirmed that the usage of small public spaces could be measured and quantified effectively and efficiently.
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Aprendizaje Profundo , Ambiente , Características de la Residencia , GeografíaRESUMEN
To explore the regularity of traditional Chinese patent medicines for the treatment of hyperlipidemia recorded in Newly Edited National Chinese Traditional Patent Medicines,the Composition Principles of Chinese Patent Drugs,New Drug Conversion Standard,the Compilation of National Standard for Traditional Chinese Medicines and Chinese Pharmacopoeia. Researchers extracted the information of prescriptions from these cases according to the inclusion and exclusion criteria. Then microsoft excel 2010 was used to conduct frequency statistics and count the frequency of traditional Chinese medicine. SPSS Clementine( ver.12. 0) and SPSS( ver. 18. 0)were adopted respectively for frequency analysis,association rules analysis,cluster analysis and factor analysis. Besides,KMO test and Bartlett spherical test were performed for factor adaptation test. Finally,a total of 173 traditional Chinese medicines were included,involving 94 Chinese patent medicine prescriptions. The frequency results of traditional Chinese medicine showed that there were 33 kinds of high-frequency traditional Chinese medicine,mainly including those for tonifying medicine,activating blood and resolving stasis and blood-stasis,and clearing damp. The association rules analysis found out 12 association rules of drug pairs,3-herb pairs of 25 and4-herb pairs of 6. Totally 11 medicine groups with relevance were respectively extracted by cluster analysis. KMO test and Bartlett spherical test indicated that the method was suitable for factor analysis and 11 common factors were respectively extracted by factor analysis. The association rules reflected the therapeutic method for tonify the liver and kidney,activating blood and resolving stasis. Cluster analysis and factor analysis showed the therapeutic method of Qi-enriching and Yin-nourishing,and the factor analysis focused more on removing blood stasis and dampness. The decision tree with hawthorn as the dependent variable reflects the importance of alisma orientalis and fructus schisandrae in the drug matching. In conclusion,data mining technique can comprehensively analyze the regularity of prescriptions of traditional Chinese patent medicine for hyperlipidemia,and is helpful for guiding the development of Chinese patent medicines and the clinical practice of traditional Chinese medicine.