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Hong Kong, renowned for its densely packed urban areas, poses unique challenges for understanding the effects of buildings on local meteorological conditions. To address this, the Hong Kong Observatory has started building a network of urban meteorological monitoring stations since 2017 for monitoring, analysing and studying urban microclimate. This paper presents an observational and numerical study focusing on wind measurements obtained from wind sensors installed on two smart lampposts in Tsim Sha Tsui, a major urban area in Hong Kong. Two representative high wind conditions in Hong Kong, Super Typhoon Saola in 2023 and a strong monsoon case characterized by prevailing easterly winds, are considered. With the use of high resolution computational fluid dynamic simulations, major features of actual observations can be reproduced. This suggests that district scale or even street scale weather services could be possible in the future with sufficient computational power.

SUMMARY: The effect of varied molecular weight (MW) chitosan oligosaccharides (COS) supplementation on growth performance, carcass trait, meat quality and fat metabolism in indigenous yellow-feathered chickens was investigated. A total of 400-day-old female Lingnanhuang yellow-feathered chicks were randomly allotted to 1 of 5 treatments (8 replicate cages of 10 chicks per cage) and fed a corn-soybean meal based diet containing 5.8 g/kg of COS with MW of 0 (control), 600 (Cs6), 1,200 (Cs12), 2,400 (Cs24), and 3,600 (Cs36) Da for 56 d. The birds in Cs36 group exhibited better overall (0–56 d) feed efficiency (P < 0.05). Both Cs24 and Cs36 feeding decreased (P < 0.05) the liver and abdominal fat but only Cs36 decreased (P < 0.05) the subcutaneous fat. In the Cs24 and Cs36 groups, there was an improvement in the meat quality as evidenced by a decrease (P < 0.05) in drip loss of breast muscle as compared with the control and Cs6 groups. The liver lipid catabolism was enhanced (P < 0.05) by the 2,400 Da and 3,600 Da COS caused by an increase in lipoprotein lipase activity and mRNA expression, which might also be the reason for the reduced carcass fat deposition. In conclusion, the 3,600 Da COS supplementation significantly improved the overall feed conversion ratio of indigenous yellow-feathered chickens. Both 2,400 Da and 3,600 Da COS were effective in reducing liver and abdominal fat deposition, decreasing drip loss of breast muscle and promoting liver fat catabolism. The study highlighted the importance of the chitosan oligosaccharide MW when added to chicken diets.

Starting from realistic nuclear forces, we have developed a core Gamow shell model which can describe resonance and continuum properties of loosely-bound or unbound nuclear systems. To describe properly resonance and continuum, the Berggren representation has been employed, which treats bound, resonant and continuum states on equal footing in a complex-momentum (complex-k) plane. To derive the model-space effective interaction based on realistic forces, the full Qˆ-box folded-diagram renormalization has been, for the first time, extended to the nondegenerate complex-k space. The CD-Bonn potential is softened by using the Vlow-k method. Choosing 16O as the inert core, we have calculated sd-shell neutron-rich oxygen isotopes, giving good descriptions of both bound and resonant states. The isotopes 25,26O are calculated to be resonant even in their ground states.

The aims of the study were to measure the mRNA expression of brain-derived neurotrophic factor (BDNF) in bovine oocytes and early embryos derived from in vitro fertilization (IVF), parthenogenetic activation (PA) and nuclear transfer (NT), and to investigate the effects of BDNF on the development of IVF and parthenogenetic embryos. Bovine oocytes matured in vitro for 22 h were in vitro fertilized or parthenogenetic activated. By reverse transcription-PCR and quantitative real-time PCR, we found that germinal vesicle (GV) oocytes, metaphase II (MII) oocytes, 4-cell and 8-cell embryos, morulae, and blastocysts were all shown to express mRNA for BDNF. The mRNA levels for BDNF gene were different in bovine oocytes and IVF embryos at different stages (P < 0.01), with the highest expression in MII oocytes and the lowest expression in 8-cell embryos. The mRNA for BDNF was highly expressed in the PA and IVF blastocysts compared to the NT blastocysts (P < 0.01). Supplementation of culture media with BDNF at the concentration of 40 μg/l caused a significant increase in the rates of in vitro-fertilized blastocyst formation (P < 0.05) and parthenogenetic blastocyst formation (P < 0.05). However, the rate of oocyte cleavage in BDNF groups was not significantly different from that in the BDNF-free control (P > 0.05) after IVF or PA. We have also investigated the effects of BDNF on the growth of granulosa cells, which were used for co-culture of bovine early embryos. The results revealed that supplementation of culture media with 20 μg/l BDNF promoted the growth of granulosa cells (P < 0.01). Taken together, these results provided evidence for the role of neurotrophins in promoting early embryonic development as well as in the growth of granulosa cells by the co-culture system, indicating that BDNF can directly or indirectly promote bovine early embryo development.