Remove Cosine Window from Correlation Filter-based Visual Trackers: When and How

Correlation filters (CFs) have been continuously advancing the state-of-the-art tracking performance and have been extensively studied in the recent few years. Most of the existing CF trackers adopt a cosine window to spatially reweight base image to alleviate boundary discontinuity. However, cosine window emphasizes more on the central region of base image and has the risk of contaminating negative training samples during model learning. On the other hand, spatial regularization deployed in many recent CF trackers plays a similar role as cosine window by enforcing spatial penalty on CF coefficients. Therefore, we in this paper investigate the feasibility to remove cosine window from CF trackers with spatial regularization. When simply removing cosine window, CF with spatial regularization still suffers from small degree of boundary discontinuity. To tackle this issue, binary and Gaussian shaped mask functions are further introduced for eliminating boundary discontinuity while reweighting the estimation error of each training sample, and can be incorporated with multiple CF trackers with spatial regularization. In comparison to the counterparts with cosine window, our methods are effective in handling boundary discontinuity and sample contamination, thereby benefiting tracking performance. Extensive experiments on three benchmarks show that our methods perform favorably against the state-of-the-art trackers using either handcrafted or deep CNN features. The code is publicly available at https://github.com/lifeng9472/Removing_cosine_window_from_CF_trackers.Comment: 13 pages, 7 figures, submitted to IEEE Transactions on Image Processin

Reexamining actin polymerization in maintaining cadherin mediated cell-cell adhesion

Inhibiting actin polymerization disrupts the cell-cell junction showing that continuous actin polymerization is required for maintaining tissue cohesion. The actin cytoskeleton maintains cell-cell cohesion by converting weak homophilic bonds between the cadherin cell adhesion molecules into strong adhesion. However, the most popular models to explain the role of actin at the junction do not require dynamic actin networks. According to these models, actin polymerization builds contractile actomyosin networks which pull on cadherins and strengthen the mechanosensitive bonds (the contractility model) or the fence around clusters of cadherins which mediate stronger adhesion than single cadherins (the clustering model). Actin polymerization could no doubt achieve these functions but what might be the most direct or evolutionarily primitive function of actin polymerization at junctions? Here I propose an alternative model which emphasizes on the most conceptually direct consequence of continuous actin polymerization: using the energy from ATP hydrolysis by the polymerization motor to drive plasma membrane protrusions; actin polymerization dependent, outwardly directed protrusive forces press the membranes of neighboring cells together in favor of cadherin homophilic binding. In Chapter 2, I show that filopodium-like actin microspikes protrude perpendicularly at the apical junction to deliver cadherins to where cadherins are missing on the neighboring cell, functioning as a repair mechanism for small defects in the otherwise continuous cadherin belt; myosin II contractility, contrary to the popular belief, actually destabilizes junctions. In Chapter 3, I show that interdigitated actin microspikes are engaged with one another through cadherin homophilic bonds at lateral junctions; patches of microspikes appear as micrometer sized cadherin puncta and are a stable form of junction in established epithelia, not only in newly forming tissues; molecular clustering of cadherins persists independently of actin polymerization and do not account for mesoscale cadherin puncta as long believed. Both apical and lateral microspikes depend on actin polymerization factors Arp2/3, EVL, and CRMP-1 and are antagonized by myosin II contractility. Lacking microspikes destabilizes apical and lateral junctions; lacking myosin II ATPase function has no such effect. My works explain why continuous actin polymerization is required for maintaining strong cadherin adhesion while myosin II contractility is dispensable. My works provide a parsimonious explanation for the continuous actin polymerization at junctions by invoking a process (fast, micron-sized membrane protrusion and retraction) that can be achieved by no other cellular apparatus than the dynamic actin cytoskeleton

Effects of duration of long-acting GnRH agonist downregulation on assisted reproductive technology outcomes in patients with adenomyosis: a retrospective cohort study

ObjectivesTo elucidate the relationship between long-acting GnRH agonist (GnRHa) downregulation and assisted reproductive technology (ART) outcomes and identify the optimal duration of downregulation in patients with adenomyosis.DesignRetrospective cohort study.ParticipantsThe study was designed to evaluate ART outcomes in adenomyosis patients with and without GnRHa downregulation between January 2016 and December 2020. A total of 374 patients with adenomyosis (621 cycles) were included with 281 cycles in downregulation group versus 340 cycles in non-downregulation group. After 1:1 propensity score matching (PSM), a sample size of 272 cycles in each group was matched. The matched downregulation group was further divided into 1-month (147 cycles), 2-months (72 cycles), and ≥3 months downregulation (53 cycles) subgroups. Stratification analysis was conducted on pregnancy outcomes in 239 fresh embryo transfer (ET) cycles and 305 frozen embryo transfer (FET) cycles.ResultsThe downregulation group had larger mean diameter of initial uterus and higher proportion of severer dysmenorrhea compared to non-downregulation group. The pregnancy-related parameters in GnRHa downregulation group were similar to those in non-downregulation group, except for higher late miscarriage rate (MR) (13.4% vs. 3.1%, P = 0.003). The subgroup comparisons in fresh ET cycles indicated that implantation rate (75.0% vs. 39.2%, P = 0.002), biochemical pregnancy rate (91.7% vs. 56.0%, P = 0.036) and clinical pregnancy rate (83.3% vs. 47.0%, P = 0.016) could be improved by prolonged GnRHa downregulation (≥3 months), whereas late MR was difficult to be reversed (30.0% vs. 3.2%, P = 0.017). In FET cycles, higher MR (53.6% vs. 29.9%, P = 0.029; 58.8% vs. 29.9%, P = 0.026) and lower live birth rate (18.8% vs. 34.1%, P = 0.023; 17.1% vs. 34.1%, P = 0.037) were observed in the 1-month and ≥3 months downregulation group, while no differences were found in the 2-months downregulation group compared to the non-downregulation group.ConclusionIn patients with severer adenomyosis, long-acting GnRHa downregulation might be correlated with improved ART outcomes. In fresh ET cycles, prolonged downregulation (≥3 months) might be beneficial to improve live birth rate, which needed to be verified by further study with larger sample. In FET cycles, the optimal duration of downregulation was not certain and still needed further exploration

Study on the relationship between tsunami waves in dam break state and initial water levels

Tsunami wave characteristics are greatly influenced by the initial water level when they attack structures. In this study, experimental and numerical investigations were conducted to investigated the relationship between tsunami wave characteristics and initial water levels. Results showed that, the wave height, wave velocity, and Froude number increase with the increase of tsunami wave intensity; the time history of water levels were influenced by the different initial water level conditions; the analytical solution proposed by Chanson (2005) may be extended to wet-bed conditions (for initial water level < 0.36 tsunami bore height in our experimental set-up). Due to the limitations of experimental ranges in the laboratory, the validated numerical model can provide more results for wider experimental ranges for tsunami bore investigations. It was observed from numerical results that, tsunami bore height increases with the increase of reservoir water level; tsunami bore velocity decreases with the increased initial water level on the bed; as the initial water level on the bed gradually increases, the mean tsunami bore Froude number shows a downward trend

Melatonin protects against ovarian damage by inhibiting autophagy in granulosa cells in rats

Objectives: This study sought to further verify the protective mechanism of Melatonin (MT) against ovarian damage through animal model experiments and to lay a theoretical and experimental foundation for exploring new approaches for ovarian damage treatment. Method: The wet weight and ovarian index of rat ovaries were weighted, and the morphology of ovarian tissues and the number of follicles in the pathological sections of collected ovarian tissues were recorded. And the serum sex hormone levels, the key proteins of the autophagy pathway (PI3K, AKT, mTOR, LC3II, LC3I, and Agt5) in rat ovarian tissues, as well as the viability and mortality of ovarian granulosa cells in each group were measured by ELISA, western blotting, CCK8 kit and LDH kit, respectively. Results: The results showed that MT increased ovarian weight and improved the ovarian index in ovarian damage rats. Also, MT could improve autophagy-induced ovarian tissue injury, increase the number of primordial follicles, primary follicles, and sinus follicles, and decrease the number of atretic follicles. Furthermore, MT upregulated serum AMH, INH-B, and E2 levels downregulated serum FSH and LH levels in ovarian damage rats and activated the PI3K/AKT/mTOR signaling pathway. Besides, MT inhibited autophagic apoptosis of ovarian granulosa cells and repressed the expression of key proteins in the autophagic pathway and reduced the expression levels of Agt5 and LC3II/I. Conclusions: MT inhibits granulosa cell autophagy by activating the PI3K/Akt/mTOR signaling pathway, thereby exerting a protective effect against ovarian damage

Directory of English/Chinese Names of Scholars in Chinese Studies - 海外中国研究学者名录（英中对照）

The Directory of English/Chinese Names of Scholars in Chinese Studies was a by-product of the "Chinese Studies in North America - Research and Resources" project. It provides both the English and the Chinese names of scholars involved in Chinese Studies mainly in North America. The Chinese names for western scholars resulted from an extensive in the relevant literature and on the internet at appropriate sites to find and authenticate the Chinese names used by these scholars. Where we could not find the Chinese name adopted by a scholar, we have transliterated their name into Chinese characters using the standard reference book 英语姓名译名手册. It is hoped that this directory will be useful for people needing to search for the Chinese names used by western scholars, or for the standard transliterations of their names into Chinese characters. Corrections of inaccurate information and addition of new names of Chinese Studies scholars worldwide are welcome. For corrections, comments and updates, please send emails to Haihui Zhang (Librarian for Chinese studies at East Asian Library, University Library System at University of Pittsburgh) at [email protected]