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1.
J Dairy Sci ; 107(8): 6178-6191, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38395405

RESUMEN

Live body weight (LBW) is one of the most important parameters for supervising the growth and development of livestock. The yak (Bos grunniens) is a special species of cattle that lives on the Qinghai-Tibetan Plateau. Yaks are more untamed than regular cattle breeds, so it is more challenging to measure their LBW. In this study, YOLOv8 yak detection and LBW estimation models were used to automatically estimate yak LBW in real time. First, the proper posture (normal posture) and individual yak identification was confirmed and then the YOLOv8 detection model was used for LBW estimation from 2-dimensional images. Yak LBW was estimated through yak body parameter extraction and a simple linear regression between the estimated yak LBW and the actual measured yak LBW. The results showed that the overall detection performance for normal yak posture was described by precision, recall, and mean average precision 50 (mAP50) indicators, reaching 81.8%, 86.0%, and 90.6%, respectively. The best yak identification results were represented by precision, recall, and mAP50 values of 97.8%, 96.4%, and 99.0%, respectively. The yak LBW estimation model achieved better results for the 12-mo-old yaks with shorter hair, with values for R2, root mean square error, mean absolute percentage error, and multiple R of 0.96, 2.43 kg, 1.69%, and 0.98, respectively. The results demonstrate that yak LBW can be estimated and monitored in real time using this approach. This study has the potential to be used for daily yak LBW monitoring in an unstressed manner and to save considerable labor resources for large-scale livestock farms. In the future, to reduce the limitations caused by the impacts of yak hair and light condition, datasets of dairy cows and yaks of different ages will be used to improve and generalize the model.


Asunto(s)
Algoritmos , Peso Corporal , Animales , Bovinos , Femenino
2.
ACS Appl Mater Interfaces ; 15(32): 38433-38443, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37535436

RESUMEN

The integration of radionuclide iodine molecules in metal-organic frameworks (MOFs) for organic synthesis is attracting considerable research attention due to their specific catalytic performance. However, understanding the comprehensive catalytic behaviors of different types of molecular iodine encapsulated in MOFs for a sequential organic transformation is a great challenge. To address this issue, we have designed two triethylenediamine-functionalized MOFs assembled from 1,3,5-tricarboxyphenyl-2-(triethylenediaminemethyl)benzene-linker and {Cd(COO)3N} or {Cu4(u3-OH)2(COO)6N} clusters. Both MOFs show good stability and adsorption of I2 in the solution and vapor phases. Catalysts obtained after treatment with ethyl acetate present efficient catalytic activity in hydrolysis/alkylation tandem reactions in water. The mechanistic investigations disclose a sequential catalytic process comprising a "hidden" Brønsted acid catalytic hydrolysis of acetals to aldehydes followed by the I2-bonding Lewis acid catalytic alkylation of aldehydes to 3,3'-disubstituted 1H-indoles.

3.
Front Chem ; 9: 732542, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34631659

RESUMEN

This study developed a cost-efficient hydration/asymmetric transfer hydrogenation (ATH) process for the one-pot synthesis of valuable chiral alcohols from alkynes. During this process, the initial homogeneous cobaloxime-catalyzed hydration of alkynes was followed by heterogeneous Ru/diamine-catalyzed ATH transformation of the in-situ generated ketones, which provided varieties of chiral alcohols in good yields with up to 99% ee values. The immobilized Ru/diamine catalyst could be recycled at least three times before its deactivation in the sequential reaction system. This work shows a general method for developing one-pot asymmetric sequential catalysis towards sustainable organic synthesis.

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