From outside-in to inside-out: galaxy assembly mode depends on stellar mass

In this Letter, we investigate how galaxy mass assembly mode depends on stellar mass $M_{\ast}$, using a large sample of $\sim$10, 000 low redshift galaxies. Our galaxy sample is selected to have SDSS R_{90}>5\arcsec.0, which allows the measures of both the integrated and the central NUV$-r$ color indices. We find that: in the $M_{\ast}-($ NUV$-r$) green valley, the M_{\ast}<10^{10}~M_{\sun} galaxies mostly have positive or flat color gradients, while most of the M_{\ast}>10^{10.5}~M_{\sun} galaxies have negative color gradients. When their central $D_{n}4000$ index values exceed 1.6, the M_{\ast}<10^{10.0}~M_{\sun} galaxies have moved to the UV red sequence, whereas a large fraction of the M_{\ast}>10^{10.5}~M_{\sun} galaxies still lie on the UV blue cloud or the green valley region. We conclude that the main galaxy assembly mode is transiting from "the outside-in" mode to "the inside-out" mode at M_{\ast} 10^{10.5}~M_{\sun}. We argue that the physical origin of this is the compromise between the internal and the external process that driving the star formation quenching in galaxies. These results can be checked with the upcoming large data produced by the on-going IFS survey projects, such as CALIFA, MaNGA and SAMI in the near future.Comment: Accepted for publication in ApJL,6 pages, 5 figure

FishMOT: A Simple and Effective Method for Fish Tracking Based on IoU Matching

The tracking of various fish species plays a profoundly significant role in understanding the behavior of individual fish and their groups. Present tracking methods suffer from issues of low accuracy or poor robustness. In order to address these concerns, this paper proposes a novel tracking approach, named FishMOT (Fish Multiple Object Tracking). This method combines object detection techniques with the IoU matching algorithm, thereby achieving efficient, precise, and robust fish detection and tracking. Diverging from other approaches, this method eliminates the need for multiple feature extractions and identity assignments for each individual, instead directly utilizing the output results of the detector for tracking, thereby significantly reducing computational time and storage space. Furthermore, this method imposes minimal requirements on factors such as video quality and variations in individual appearance. As long as the detector can accurately locate and identify fish, effective tracking can be achieved. This approach enhances robustness and generalizability. Moreover, the algorithm employed in this method addresses the issue of missed detections without relying on complex feature matching or graph optimization algorithms. This contributes to improved accuracy and reliability. Experimental trials were conducted in the open-source video dataset provided by idtracker.ai, and comparisons were made with state-of-the-art detector-based multi-object tracking methods. Additionally, comparisons were made with idtracker.ai and TRex, two tools that demonstrate exceptional performance in the field of animal tracking. The experimental results demonstrate that the proposed method outperforms other approaches in various evaluation metrics, exhibiting faster speed and lower memory requirements. The source codes and pre-trained models are available at: https://github.com/gakkistar/FishMO

Unusual cross-shelf transport driven by the changes of wind pattern in a marginal sea

Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 126(11), (2021): e2021JC017526, https://doi.org/10.1029/2021JC017526.The traditional understanding of the regional circulation in the Northwest Pacific marginal seas is that the Korean Coastal Current flows southward, following the isobaths of 20–50 m. However, an unusual tongue-shaped structure of cold water is observed in satellite SST data in January 2017, indicating a possible offshore spread of cold coastal water into the middle Southern Yellow Sea (SYS). Additional observations, including in situ hydrographic data as well as direct current measurement, also suggest this cross-shelf transport of the Korean Coastal Water in January 2017. Our analysis shows that this flow breaks through the isobaths at ∼37°N, moves southward between 50–75 m, and eventually veers anti-cyclonically at ∼35°N to join the western slope of the SYS. This circulation pattern is further supported by heat budget analysis. Diagnosis of potential vorticity (PV) reveals that the elevated negative PV anomaly imposed by surface wind stress favors this unusual cross-shelf transport. The change of wind pattern, although under a deceasing wind speed condition, plays an important role. This work provides an alternative view of the wintertime circulation pattern and motivates future studies of the variability of the coastal currents over interannual and longer time scales in the SYS.his study was supported by the Shandong Provincial Key Research and Development Program (2019JZZY020713, 2019GHY112057), the National Key Research and Development Program (2016YFC1401406, 2016YFA0600900), the National Natural Science Foundation of China (42076010, 42130403), National Fund Committee-Shandong joint fund (U1706215), the Fundamental Research Funds for the Central Universities (2020042010), and Ocean University of China-Woods Hole Oceanographic Institution Cooperative Research Initiative (24887).2022-05-0

Period-2: a tumor suppressor gene in breast cancer

Previous reports have suggested that the ablation of the Period 2 gene (Per 2) leads to enhanced development of lymphoma and leukemia in mice. Employing immunoblot analyses, we have demonstrated that PER 2 is endogenously expressed in human breast epithelial cell lines but is not expressed or is expressed at significantly reduced level in human breast cancer cell lines. Expression of PER 2 in MCF-7 breast cancer cells significantly inhibited the growth of MCF-7 human breast cancer cells, and, when PER 2 was co-expressed with the Crytochrome 2 (Cry 2) gene, an even greater growth-inhibitory effect was observed. The inhibitory effect of PER 2 on breast cancer cells was also demonstrated by its suppression of the anchorage-independent growth of MCF-7 cells as evidenced by the reduced number and size of colonies. A corresponding blockade of MCF-7 cells in the G1 phase of the cell cycle was also observed in response to the expression of PER 2 alone or in combination with CRY 2. Expression of PER 2 also induced apoptosis of MCF-7 breast cancer cells as demonstrated by an increase in PARP [poly (ADP-ribose) polymerase] cleavage. Finally, our studies demonstrate that PER 2 expression in MCF-7 breast cancer cells is associated with a significant decrease in the expression of cyclin D1 and an up-regulation of p53 levels

Prevalence and Risk Factors Associated with Prehypertension among Young and Middle-Aged Health Check-Up Population in Guangzhou

Objective: To provide basic information and theories for prehypertension early intervention, a systematic analysis of the epidemic status and risk factors among young and middle-aged was carried out here. Methods: This study relied on the data bank of a health check-up population of a class a tertiary general hospital in Guangdong province in 2015. Total 9540 young and middle-aged adults were enrolled, and 733 people were included to find out the effect with lifestyle in these crowd. Principal Components Analysis (PCA) of Factor (FA) was used to identify dietary patterns. The logistic regression model was used to find the risk factors of prehypertension. Results: Among 9540 young and middle-aged cases, the incidence of prehypertension was 36.6%. Moreover, the average age, proportion of male gender, overweight, FBG (fasting blood glucose), dyslipidemia, and hyperuricemia were significantly higher in the prehypertension group than in the optimal BP group. Multivariate logistic regression analysis indicated that age, total cholesterol, triglycerides, uric acid, body mass index and HR (heart rate) were risk factors, and female was a protective factor for prehypertension. Among 733 cases, the incidence of prehypertension was 35.1%. The proportion of smoking, drinking, physical workers, moderate and severe physical activity, and the intake of meat, dietary energy were significantly higher in the prehypertension group than in the optimal BP group. Dietary patterns included “meat model”, “spice model”, “main vegeTables model” and “high protein model”. Multivariate logistic regression analysis indicated that age, drinking were risk factors for prehypertension, while dietary milk intake, dietary magnesium intake were protective factors. Conclusions: Prehypertension is highly prevalent in Guangzhou. However, education about effective lifestyle modifications as an alcohol limit, increasing the intake of dairy products, and magnesium may intervene in the development of prehypertension. But how to develop targeted interventions for such groups need to be further explored. The present study would lay the theoretical foundation and basic data for the next step