The emerging value of the viroid model in understanding plant responses to foreign RNAs

RNAs play essential roles in various biological processes. Mounting evidence has demonstrated that RNA subcellular localization and intercellular trafficking govern their functions in coordinating plant growth at the organismal level. Beyond that, plants constantly encounter foreign RNAs (i.e., RNAs from pathogens including viruses and viroids). The subcellular localizations of RNAs are crucial for their function. While numerous types of RNAs (i.e., mRNAs, small RNAs, rRNAs, tRNAs, and long noncoding RNAs) have been found to traffic in a non-cell-autonomous fashion within plants, the underlying regulatory mechanism remains unclear. Viroids are single-stranded circular noncoding RNAs, which entirely rely on their RNA motifs to exploit cellular machinery for organelle entry and exit, cell-to-cell movement through plasmodesmata, and systemic trafficking. Viroids represent an excellent model to dissect the role of RNA 3-dimensional (3D) structural motifs in regulating RNA movement. Using nuclear-replicating viroids as a model, we showed that cellular Importin alpha-4 is likely involved in viroid RNA nuclear import, empirically supporting the involvement of Importin-based cellular pathway in RNA nuclear import. We also confirmed the involvement of a cellular protein (Virp1) that binds both Importin alpha-4 and viroids. Moreover, a conserved C-loop in nuclear-replicating viroids serves as a key signal for nuclear import. Disrupting C-loop impairs Virp1 binding, viroid nuclear accumulation and infectivity. Further, C-loop exists in a subviral satellite noncoding RNA that relies on Virp1 for nuclear import. On the other hand, no viroid can systemically infect the model plant Arabidopsis thaliana, suggesting the existence of non-host resistance yet to be understood. Here, we attempted to test whether a gene involved in RNA silencing, RNA-dependent RNA polymerase 6 (RDR6), plays a role in non-host resistance in Arabidopsis. I will discuss the data below in detail

The medium over the message: differential knowledge of conservation outreach activities and implications for threatened species

Conservation outreach is regularly conducted to increase support for conservation by altering local awareness and attitudes about species or environmental issues. However, there is often little assessment of the effectiveness of these activities. We investigated knowledge of past conservation outreach in 26 villages adjacent to Bawangling National Nature Reserve, Hainan, China, which contains the last population of the Hainan gibbon (Nomascus hainanus). The medium of past outreach activities was reported most frequently by interviewees, followed by who delivered them and the outreach topic, with the fewest interviewees reporting the specific messages being communicated (the consequences of following conservation management policies). Negatively-framed messages, emphasizing prohibited activities and associated punishments, were reported more than positively-framed messages that aimed to foster conservation support. Male interviewees and those with higher education levels reported more aspects of past activities. The Hainan gibbon had higher salience than other threatened native species, and reporting the occurrence (but not necessarily the content) of past outreach was associated with increased likelihood of knowing that gibbons were threatened. These findings highlight the need for conservation outreach to increase both exposure and retention of key messages among target audiences. Meaningful and concrete conservation benefits should be communicated to local communities, and the effectiveness of outreach using a flagship species could be expanded to also improve awareness of other conservation-priority species within the same landscape

The Attenuation of Moutan Cortex on Oxidative Stress for Renal Injury in AGEs-Induced Mesangial Cell Dysfunction and Streptozotocin-Induced Diabetic Nephropathy Rats

Oxidative stress (OS) has been regarded as one of the major pathogeneses of diabetic nephropathy (DN) through damaging kidney which is associated with renal cells dysfunction. The aim of this study was to investigate whether Moutan Cortex (MC) could protect kidney function against oxidative stress in vitro or in vivo. The compounds in MC extract were analyzed by HPLC-ESI-MS. High-glucose-fat diet and STZ (30 mg kg−1) were used to induce DN rats model, while 200 μg mL−1 AGEs were for HBZY-1 mesangial cell damage. The treatment with MC could significantly increase the activity of SOD, glutathione peroxidase (GSH-PX), and catalase (CAT). However, lipid peroxidation malondialdehyde (MDA) was reduced markedly in vitro or in vivo. Furthermore, MC decreased markedly the levels of blood glucose, serum creatinine, and urine protein in DN rats. Immunohistochemical assay showed that MC downregulated significantly transforming growth factor beta 2 (TGF-β2) protein expression in renal tissue. Our data provided evidence to support this fact that MC attenuated OS in AGEs-induced mesangial cell dysfunction and also in high-glucose-fat diet and STZ-induced DN rats

Hybrid Artificial Root Foraging Optimizer Based Multilevel Threshold for Image Segmentation

This paper proposes a new plant-inspired optimization algorithm for multilevel threshold image segmentation, namely, hybrid artificial root foraging optimizer (HARFO), which essentially mimics the iterative root foraging behaviors. In this algorithm the new growth operators of branching, regrowing, and shrinkage are initially designed to optimize continuous space search by combining root-to-root communication and coevolution mechanism. With the auxin-regulated scheme, various root growth operators are guided systematically. With root-to-root communication, individuals exchange information in different efficient topologies, which essentially improve the exploration ability. With coevolution mechanism, the hierarchical spatial population driven by evolutionary pressure of multiple subpopulations is structured, which ensure that the diversity of root population is well maintained. The comparative results on a suit of benchmarks show the superiority of the proposed algorithm. Finally, the proposed HARFO algorithm is applied to handle the complex image segmentation problem based on multilevel threshold. Computational results of this approach on a set of tested images show the outperformance of the proposed algorithm in terms of optimization accuracy computation efficiency

PriWhisper: Enabling Keyless Secure Acoustic Communication for Smartphones

Short-range wireless communication technologies have been used in many security-sensitive smartphone applications and services such as contactless micro payment and device pairing. Typically, the data confidentiality of the existing short-range communication systems relies on so-called key-exchange then encryption mechanism. Namely, both parties need to spend extra communication to establish a common key before transmitting their actual messages, which is inefficient, especially for short communication sessions. In this work, we present PriWhisper -- a keyless secure acoustic short-range communication system for smartphones. It is designed to provide a purely software-based solution to secure smartphone short-range communication without the key agreement phase. PriWhisper adopts the emerging friendly jamming technique from radio communication for data confidentiality. The system prototype is implemented and evaluated on several Android smartphone platforms for efficiency and usability. We theoretically and experimentally analyze the security of our proposed acoustic communication system against various passive and active adversaries. In particular, we also study the (in)separability of the data signal and jamming signal against Blind Signal Segmentation (BSS) attacks such as Independent Component Analysis (ICA). The result shows that PriWhisper provides sufficient security guarantees for commercial smartphone applications and yet strong compatibilities with most legacy smartphone platforms

Attributions of emission-reduction and meteorological conditions to typical heavy pollution episodes in a cold metropolis, northeast China

Heavy pollution episodes frequently occurred in winter in northeast China due to the multiple anthropogenic emissions coupled with adverse meteorological conditions, which increased the difficulty of environmental pollution control. To better enact strategies for mitigating air pollution in the post-pandemic era, daily pollutant concentration monitoring and meteorological data were used to evaluate the changes and meteorological factors of air pollutants before (2019) and during (2020) the lockdown in Harbin City, northeast China. Moreover, typical pollution episodes under COVID-19 lockdown were identified, and their emission sources, meteorology conditions, and regional pollution transportation were analyzed. The results showed significant decreases in NO2, PM10 and CO, while O3 increased, and no differences in PM2.5 and SO2 during the lockdown compared with non-lockdown periods. It indicated that reduced activities of transportation resulted in reductions of NO2 concentrations by 16%, and stationary emission sources were less affected. Correlation between PM2.5 and O3 tended to change from positive to negative as the threshold of PM2.5 = 90 μg m−3, with the main controlling factor changed from their common gaseous precursors to meteorological conditions (temperature <0°C and wind speed <2 m s−1). Pollution days were concentrated in the COVID-19 lockdown period with PM2.5 as the primary pollutant. SO2 dominant pollution and PM2.5 dominant pollution were distinguished from six sustained heavy pollution events. PM2.5 and SO2 played essential roles in SO2 dominant pollution, which derived from local emissions of coal combustion and firework discharge. PM2.5 dominant pollution might be chemical transformed from coal burning, vehicle exhaust, and other secondary precursors, which was affected and aggravated by CO, NO2, high relative humidity and low wind speed affected by local emission and long-distance transport

Accuracy of triage strategies for human papillomavirus DNA-positive women in low-resource settings: A cross-sectional study in China

CareHPV is a human papillomavirus (HPV) DNA test for low-resource settings (LRS). This study assesses optimum triage strategies for careHPV-positive women in LRS