Analysis on the effects of ecological conservation redline policies in the Pearl River Delta area, China

IntroductionThe ecological conservation redline (ECR) policies conducted in China are an important innovation to protect biodiversity, safeguard ecological security, and achieve sustainable development. The Pearl River Delta (PRD) area implemented the ECR policies in 2005.MethodsThis study examines the contrast between the 15 years before and after 2005. It also reveals the ECR policies' effects by comparing land use change, landscape pattern index, and habitat quality inside (IECR) and outside (OECR) the ECR area. Results and discussionThe results suggest that: (1) The ECR area has served as an ecological barrier in maintaining the stability of natural ecosystems. Over the past 30 years, the PRD area significantly changed land use types and ecosystems, mainly concentrated in the central plains and estuaries. Specifically, in the IECR, land use change was relatively stable, with a decrease of 0.05% and 0.57% in ecological land and an increase of 0.28% and 0.68% in construction land before and after 2005. In contrast, the OECR area land use changed dramatically, with a decrease of 0.37% and 1.36% in ecological land and an increase of 7.06% and 5.02% in construction land before and after 2005. (2) A general trend of landscape fragmentation exists in the study area. The contagion (CONTAG) in the IECR area is higher than in the OECR. The Shannon's diversity index (SHDI) in the IECR is lower than in the OECR area, which indicates a high degree and rapid landscape fragmentation in the OECR area. (3) Over 85% of the IECR scale had a habitat quality of 0.8–1, while the OECR area had an almost half scale with a habitat quality of 0–0.2. On the whole, the ecological stability and landscape connectivity of in the IECR area was higher than that of the OECR area. This indicates that the prohibitions on human disturbance, industrial construction, and logging activities in the IECR area allow green vegetation to succumb under natural conditions. Habitat quality in the IECR area was also higher than that of the OECR area in the PRD area, revealing that the quality of green development in the IECR area was higher. Finally, the ECR policies’ implementation has protected the environment in the PRD area and will provide experience for ecological conservation in other areas

The Next Generation Virgo Cluster Survey. X. Properties of Ultra-Compact Dwarfs in the M87, M49 and M60 Regions

We use imaging from the Next Generation Virgo cluster Survey (NGVS) to present a comparative study of ultra-compact dwarf (UCD) galaxies associated with three prominent Virgo sub-clusters: those centered on the massive, red-sequence galaxies M87, M49 and M60. We show how UCDs can be selected with high completeness using a combination of half-light radius and location in color-color diagrams ($u^*iK_s$ or $u^*gz$). Although the central galaxies in each of these sub-clusters have nearly identical luminosities and stellar masses, we find large differences in the sizes of their UCD populations, with M87 containing ~3.5 and 7.8 times more UCDs than M49 and M60, respectively. The relative abundance of UCDs in the three regions scales in proportion to sub-cluster mass, as traced by X-ray gas mass, total gravitating mass, number of globular clusters, and number of nearby galaxies. We find that the UCDs are predominantly blue in color, with ~85% of the UCDs having colors similar to blue GCs and stellar nuclei of dwarf galaxies. We present evidence that UCDs surrounding M87 and M49 may follow a morphological sequence ordered by the prominence of their outer, low surface brightness envelope, ultimately merging with the sequence of nucleated low-mass galaxies, and that envelope prominence correlates with distance from either galaxy. Our analysis provides evidence that tidal stripping of nucleated galaxies is an important process in the formation of UCDs.Comment: 37 pages, 40 figures. To appear in The Astrophysical Journa

The properties of bright globular clusters, ultra-compact dwarfs and dwarf nuclei in the Virgo core: hints on origin of ultra-compact dwarf galaxies (UCDs)

Based on the data from the Next Generation Virgo cluster Survey (NGVS), we statistically study the photometric properties of globular clusters (GCs), ultra-compact dwarfs (UCDs) and dwarf nuclei in the Virgo core (M87) region. We found an obvious negative color (g - z) gradient in GC system associate with M87, i.e. GCs in the outer regions are bluer. However, such color gradient does not exist in UCD system, neither in dwarf nuclei system around M87. In addition, we found that many UCDs are surrounded by extended, low surface brightness envelopes. The dwarf nuclei and UCDs show different spatial distributions from GCs, with dwarf nuclei and UCDs (especially for the UCDs with visible envelopes) lying at larger distances to the Virgo center. These results support the view that UCDs (at least for a fraction of UCDs) are more tied to dwarf nuclei than to GCs

Crystal structure of rhodopsin bound to arrestin by femtosecond X-ray laser.

G-protein-coupled receptors (GPCRs) signal primarily through G proteins or arrestins. Arrestin binding to GPCRs blocks G protein interaction and redirects signalling to numerous G-protein-independent pathways. Here we report the crystal structure of a constitutively active form of human rhodopsin bound to a pre-activated form of the mouse visual arrestin, determined by serial femtosecond X-ray laser crystallography. Together with extensive biochemical and mutagenesis data, the structure reveals an overall architecture of the rhodopsin-arrestin assembly in which rhodopsin uses distinct structural elements, including transmembrane helix 7 and helix 8, to recruit arrestin. Correspondingly, arrestin adopts the pre-activated conformation, with a ∼20° rotation between the amino and carboxy domains, which opens up a cleft in arrestin to accommodate a short helix formed by the second intracellular loop of rhodopsin. This structure provides a basis for understanding GPCR-mediated arrestin-biased signalling and demonstrates the power of X-ray lasers for advancing the frontiers of structural biology

An Overview of Trust Standards for Communication Networks and Future Digital World

Trust is an essential concept in various scenarios enabled by Information and Communication Technologies (ICT). To facilitate the implementation of trust in these scenarios, different organizations have published a series of trust frameworks. However, most existing works on trust standards only focus on a specific application domain. Unlike these works, in this paper, we provide a comprehensive overview of the current available trust standards related to communication networks and future digital world from several main organizations. We categorize these trust standards into three layers: trust foundation, trust elements, and trust applications. We then analyze these trust standards and discuss their contributions in a systematic way. We also examine the motivations behind each enforced standard, analyze their frameworks and solutions, and present their role and impact on communication works and future digital world. Finally, we offer our suggestions on the trust work that needs to be standardized in the future

Hospital infection prevention and control practices in anti-epidemic medical staff and workers during COVID-19 epidemic: investigation and countermeasures

Objective: To investigate differences in infection control awareness, and related implementation of measures between anti-epidemic medical staff and workers during the outbreak of novel coronavirus (COVID-19) infection, and to propose corresponding countermeasures. Methods: A self-designed questionnaire on the practice of infection control and implement were conducted, and 250 medical staff and workers participating in the anti-epidemic work in our hospital from March to April 2022 were investigated online. Results: A total of 208 valid questionnaires were recovered, of which 192 were valid questionnaires, including 158 medical staff (82.3%) and 34 (17.7%) workers. Before entering the isolation point, the proportion of workers vs medical staff who knew the knowledge about COVID-19, hospital infection control procedures, standardized use of masks, awareness of occupational post-exposure disposal procedures, awareness of sensory control and implementation of sensory control in living areas were 58.8% vs 89.2%, 67.6% vs 91.1%, 82.4% vs 98.7%, (58.8% vs 98.7%), (47.1% vs 98.7%), (47.1% vs 94.3%) (P<0.05). However, the proportion of discomfort such as sweating, poor breathing, dizziness and fatigue during work in the polluted area was significantly lower than those of medical staff（2.9% vs 11.5%, P<0.001）. Then targeted measures such as scenario simulation training assessment and real-time "one-to-one" on-site supervision were performed,and the infection control practice norms of these two groups have been significantly improved. The proportion of medical staff with knowledge about new coronary pneumonia and aware of the hospital infection system process increased to 99.4% (P<0.001) and to 98.7% (P=0.002), respectively, while of workers increased to 85.3% (P=0.015) and to 100% (P<0.001). The proportion of workers got a score of 90-95 on hospital infection theory and operation increased from 29.4% to 38.2%, and the proportion with a score of 95 or above increased from 32.4% to 58.8% (P<0.001). Conclusions: The implement and and awareness of infection control practice in workers is worse than those of medical staff, and workers are a high-risk group for hospital infection. The scenario simulation training and real-time assessment methods, whole process "one-to-one" on-site supervision can effectively improve the awareness and practical ability of medical staff, especially workers

NEDD4 Depletion Inhibits Hepatocellular Carcinoma Growth via Targeting PTEN

Background/Aims: Neural precursor cell-expressed developmentally down-regulated gene 4 (NEDD4) plays an important role in tumor cell growth, yet its role in hepatocellular carcinoma (HCC) remains unclear. This study is to establish NEDD4 as a prognostic biomarker by which the survival of HCC patients can be predicted and to reveal the role of NEDD4 in hepatocellular carcinoma cell growth. Methods: The expression of NEDD4 in 219 HCC specimens was assessed by immunohistochemistry. Postoperative overall survival and time to recurrence were evaluated by univariate and multivariate analyses. The roles of NEDD4 in hepatocellular carcinoma cell proliferation and invasion were determined. Results: The patients with low NEDD4 expression tumors had an average cumulative survival of 64.9 ± 6.5 months during follow-up while the patients with high NEDD4 expression tumors had an average cumulative survival of 20.3 ± 15.8 months. NEDD4 silencing inhibited Huh7 cell proliferation and altered cell cytoskeletal assembly, and NEDD4 depletion furthermore seemed to suppress cell migration and invasion. A possible molecular mechanism for the observed effects might be that NEDD4 silence led to an increase in PTEN (phosphatase and tensin homologue) expression, which in turn resulted in the inactivation of STAT3, AKT, and ERK1/2. Conclusion: Our findings indicate that NEDD4 may participate in the HCC progression and may therefore be a potential target for HCC therapy