452 research outputs found
Synthesis of thioesters through copper-catalyzed coupling of aldehydeswith thiols in water
Copper-catalyzed C–S bond formation between aldehydes and thiols in the presence of TBHP as an oxidant is described. Functional groups including chloro, trifluoromethyl, bromo, iodo, nitrile, ester and thiophene are all tolerated by the reaction conditions employed. This reaction is performed in water without the use of a surfactant. Both aryl and alkyl aldehydes couple suitably with aryl- and alkyl thiols, affording the corresponding thioesters in moderate to good yields
AdapterBias: Parameter-efficient Token-dependent Representation Shift for Adapters in NLP Tasks
Transformer-based pre-trained models with millions of parameters require
large storage. Recent approaches tackle this shortcoming by training adapters,
but these approaches still require a relatively large number of parameters. In
this study, AdapterBias, a surprisingly simple yet effective adapter
architecture, is proposed. AdapterBias adds a token-dependent shift to the
hidden output of transformer layers to adapt to downstream tasks with only a
vector and a linear layer. Extensive experiments are conducted to demonstrate
the effectiveness of AdapterBias. The experiments show that our proposed method
can dramatically reduce the trainable parameters compared to the previous works
with a minimal decrease in task performances compared with fine-tuned
pre-trained models. We further find that AdapterBias automatically learns to
assign more significant representation shifts to the tokens related to the task
in consideration.Comment: The first two authors contributed equally. This paper was published
in Findings of NAACL 202
Particle Size Effects of TiO 2
Large particle sizes having a strong light scattering lead to a significantly decreased surface area and small particle sizes having large surface area lack light-scattering effect. How to combine large and small particle sizes together is an interesting work for achieving higher solar efficiency. In this work, we investigate the solar performance influence of the dye-sensitized solar cells (DSSCs) by the multiple titanium oxide (TiO2) layers with different particle sizes. It was found that the optimal TiO2 thickness depends on the particle sizes of TiO2 layers for achieving the maximum efficiency. The solar efficiency of DSSCs prepared by triple TiO2 layers with different particle sizes is higher than that by double TiO2 layers for the same TiO2 thickness. The choice of particle size in the bottom layer is more important than that in the top layer for achieving higher solar efficiency. The choice of the particle sizes in the middle layer depends on the particle sizes in the bottom and top layers. The mixing of the particle sizes in the middle layer is a good choice for achieving higher solar efficiency
Particle Size Effects of TiO2 Layers on the Solar Efficiency of Dye-Sensitized Solar Cells
Large particle sizes having a strong light scattering lead to a significantly decreased surface area and small particle sizes having large surface area lack light-scattering effect. How to combine large and small particle sizes together is an interesting work for achieving higher solar efficiency. In this work, we investigate the solar performance influence of the dye-sensitized solar cells (DSSCs) by the multiple titanium oxide (TiO2) layers with different particle sizes. It was found that the optimal TiO2 thickness depends on the particle sizes of TiO2 layers for achieving the maximum efficiency. The solar efficiency of DSSCs prepared by triple TiO2 layers with different particle sizes is higher than that by double TiO2 layers for the same TiO2 thickness. The choice of particle size in the bottom layer is more important than that in the top layer for achieving higher solar efficiency. The choice of the particle sizes in the middle layer depends on the particle sizes in the bottom and top layers. The mixing of the particle sizes in the middle layer is a good choice for achieving higher solar efficiency
A General Procedure for the Regioselective Synthesis of Aryl Thioethers and Aryl Selenides Through C–H Activation of Arenes
A general procedure for the synthesis of aryl thioethers and aryl selenides in one-pot through sequential iridium-catalyzed C–H borylation and copper-promoted C–S and C–Se bond formation is described. Functional groups including chloro, nitro, fluoro, trifluoromethyl, and nitrogen-containing heterocycles were all tolerated under the reaction conditions. Importantly, not only aryl thiols and selenides but also their alkyl analogs were suitable coupling partners, and the products were obtained in good yields with high meta regioselectivity
Manganese-Catalyzed Cross-Coupling of Thiols with Aryl Iodides
Here we report the manganesecatalyzedcoupling reaction of thiols witharyl iodides, giving the aryl thioethers ingood to excellent yields; the system showsgood functional group tolerance and enablesthe sterically demanding aryl iodides tocouple with thiols
Effects of overexpression of IL-10, IL-12, TGF-β and IL-4 on allergen induced change in bronchial responsiveness
BACKGROUND: An increasing prevalence of allergic diseases, such as atopic dermatitis, allergic rhinitis and bronchial asthma, has been noted worldwide. Allergic asthma strongly correlates with airway inflammation caused by the unregulated production of cytokines secreted by allergen-specific type-2 T helper (Th2) cells. This study aims to explore the therapeutic effect of the airway gene transfer of IL-12, IL-10 and TGF-β on airway inflammation in a mouse model of allergic asthma. METHODS: BALB/c mice were sensitized to ovalbumin (OVA) by intraperitoneal injections with OVA and challenged by nebulized OVA. Different cytokine gene plasmids or non-coding vector plasmids were instilled daily into the trachea up to one day before the inhalatory OVA challenge phase. RESULTS: Intratracheal administration of IL-10, IL-12 or TGF-β can efficiently inhibit antigen-induced airway hyper-responsiveness and is able to largely significantly lower the number of eosinophils and neutrophils in bronchoalveolar lavage fluid of ovalbumin (OVA) sensitized and challenged mice during the effector phase. Furthermore, the effect of IL-10 plasmids is more remarkable than any other cytokine gene plasmid. On the other hand, local administration of IL-4 gene plasmids before antigen challenge can induce severe airway hyper-responsiveness (AHR) and airway eosinophilia. CONCLUSION: Our data demonstrated that anti- inflammatory cytokines, particularly IL-10, have the therapeutic potential for the alleviation of airway inflammation in murine model of asthma
Starch dust explosion and flame burn injury in a patient complicated with severe cellulites caused by non-O1 Vibrio cholerae
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