Novel segmented stacked autoencoder for effective dimensionality reduction and feature extraction in hyperspectral imaging

Stacked autoencoders (SAEs), as part of the deep learning (DL) framework, have been recently proposed for feature extraction in hyperspectral remote sensing. With the help of hidden nodes in deep layers, a high-level abstraction is achieved for data reduction whilst maintaining the key information of the data. As hidden nodes in SAEs have to deal simultaneously with hundreds of features from hypercubes as inputs, this increases the complexity of the process and leads to limited abstraction and performance. As such, segmented SAE (S-SAE) is proposed by confronting the original features into smaller data segments, which are separately processed by different smaller SAEs. This has resulted in reduced complexity but improved efficacy of data abstraction and accuracy of data classification

Molecular monitoring of causative viruses in child acute respiratory infection in endemo-epidemic situations in Shanghai

International audienceBACKGROUND: Numerous viruses are responsible for respiratory infections; however, both their distribution and genetic diversity, in a limited area and a population subgroup, have been studied only rarely during a sustained period of time. METHODS: A 2-year surveillance program of children presenting with acute respiratory infections (ARIs) was carried out to characterize the viral etiology and to assess whether using gene amplification and sequencing could be a reliable approach to monitor virus introduction and spread in a population subgroup. RESULTS: Using multiplex RT-PCR, 15 different respiratory viruses were detected within the 486 nasopharyngeal positive samples collected among 817 children aged <9-year old who presented with ARI during October 2006 to September 2008. A single virus was detected in 373 patients (45.7%), and two to four viruses in 113 patients (13.8%). The most frequent causative viruses were respiratory syncytial virus (RSV) (24.7%), human bocavirus (24.5%), and human rhinovirus (HRV) (15%). RSV was more prevalent in winter and among young infants. Cases of seasonal influenza A and B viruses were reported mainly in January and August. An increase in adenovirus infection was observed during the spring of the second year of the study. Sequence analyses showed multiple introductions of different virus subtypes and identified a high prevalence of the newly defined HRV-C species. A higher viral incidence was observed during the winter of 2008, which was unusually cold. CONCLUSIONS: This study supports the usefulness of multiplex RT-PCR for virus detection and co-infection, and for implementation of a molecular monitoring system for endemic and epidemic viral respiratory infections

Simvastatin suppresses the DNA replication licensing factor MCM7 and inhibits the growth of tamoxifen-resistant breast cancer cells

Acquired tamoxifen resistance (TamR) remains a major challenge in breast cancer endocrine therapy. The mechanism of acquiring tamoxifen resistance remains elusive, and no effective drugs are available. In this investigation, we determined that the expression of the DNA damage marker γH2AX is upregulated under minichromosome maintenance protein 7 (MCM7) knockdown in phospho Ser807/811-retinoblastoma protein (p-Rb) defect cells. In addition, the expression of p-Rb was lower in TamR cells than in parental cells, and the expression of γH2AX was significantly upregulated when MCM7 was knocked down in TamR cells. Simvastatin, an agent for hypercholesterolemia treatment, activated the MCM7/p-RB/γH2AX axis and induced DNA damage in TamR cells, especially when combined with tamoxifen. Finally, in vitro and in vivo experiments demonstrated that simvastatin combined with tamoxifen increased TamR cell apoptosis and inhibited xenograft growth. In conclusion, simvastatin may suppress TamR cell growth by inhibiting MCM7 and Rb and subsequently inducing DNA damage

Simvastatin and Atorvastatin inhibit DNA replication licensing factor MCM7 and effectively suppress RB-deficient tumors growth

Loss or dysfunction of tumor suppressor retinoblastoma (RB) is a common feature in various tumors, and contributes to cancer cell stemness and drug resistance to cancer therapy. However, the strategy to suppress or eliminate Rb-deficient tumor cells remains unclear. In the present study, we accidentally found that reduction of DNA replication licensing factor MCM7 induced more apoptosis in RB-deficient tumor cells than in control tumor cells. Moreover, after a drug screening and further studies, we demonstrated that statin drug Simvastatin and Atorvastatin were able to inhibit MCM7 and RB expressions. Further study showed that Simvastatin and Atorvastatin induced more chromosome breaks and gaps of Rb-deficient tumor cells than control tumor cells. In vivo results showed that Simvastatin and Atorvastatin significantly suppressed Rb-deficient tumor growth than control in xenograft mouse models. The present work demonstrates that ‘old' lipid-lowering drugs statins are novel weapons against RB-deficient tumors due to their effects on suppressing MCM7 protein levels

Some recent studies on hohlraum physics

Some of our recent studies on hohlraum physics are presented, mainly including simulation study on hohlraum physics experiments on SGIII prototype, the design of Au + U + Au sandwich hohlraum for ignition target, and an initial design of elliptical hohlraum and pertinent drive laser power in order to generate an ignition radiation profile

Evidence of Recombination and Genetic Diversity in Human Rhinoviruses in Children with Acute Respiratory Infection

International audienceOur study showed a high diversity of HRV strains that cause bronchitis and pneumonia in children. A predominance of HRV-C over HRV-A and HRV-B was observed, and two subspecies of HRV-C were identified, the diversity of which seemed to be related to recombination with former HRV-A strains. None of the HRV-C strains appeared to have a higher clinical impact than HRV-A or HRV-B on respiratory compromise

The non-significant correlation between landscape ecological risk and ecosystem services in Xi'an Metropolitan Area, China

As critical prerequisite for sustainable development research of social ecosystem (SDSE), the relationship between landscape security pattern and ecosystem services should be explicitly evaluated to support SDSE research. However, the existing evaluation system lacking of integrating analysts of the factors led to vague knowledge of the SDSE mechanism. To tackle this issue, this study, therefore, explored the relationship between landscape ecological risk and ecosystem services (e.g. carbon sequestration, soil conservation, water yield, crop production and residential support) at Xi’an Metropolitan Area using remote sensing data in 2010 and 2020. The results show that the overall landscape ecological risk decreased from 0.2618 to 0.2479. Although the rapid development of urban leading improvement for landscape ecological security and residential support, the total ecosystem services has declined due to the decline in water yield and crop production. Preventing the landscape ecological risk on landscape fragmentation cannot improve the level of ecosystem services. Notably, the stronger interference of human activities overwhelmingly caused a single advantageous ecosystem services with extreme risk, while the less caused multiple advantageous ecosystem services of ecological regulation with medium–low level ecological risk. Additionally, the competitive relationship between the crop production and residential support would not produce higher risk led by the intervention of human activity. The integrating of crop production and carbon sequestration (or soil conservation) resulted in high risk. Using these results, a potential spatial plan of Xi'an Metropolitan Area is then made based on multiple advantageous areas of ecosystem services. This study benefits decision-making for regional comprehensive risk prevention, future spatial pattern planning and development orientation, and sustainable development research of social ecosystem

Bubble-water/catalyst triphase interface microenvironment accelerates photocatalytic OER via optimizing semi-hydrophobic OH radical

Photocatalytic water splitting (PWS) as the holy grail reaction for solar-to-chemical energy conversion is challenged by sluggish oxygen evolution reaction (OER) at water/catalyst interface. Experimental evidence interestingly shows that temperature can significantly accelerate OER, but the atomic-level mechanism remains elusive in both experiment and theory. In contrast to the traditional Arrhenius-type temperature dependence, we quantitatively prove for the first time that the temperature-induced interface microenvironment variation, particularly the formation of bubble-water/TiO2(110) triphase interface, has a drastic influence on optimizing the OER kinetics. We demonstrate that liquid-vapor coexistence state creates a disordered and loose hydrogen-bond network while preserving the proton transfer channel, which greatly facilitates the formation of semi-hydrophobic •OH radical and O-O coupling, thereby accelerating OER. Furthermore, we propose that adding a hydrophobic substance onto TiO2(110) can manipulate the local microenvironment to enhance OER without additional thermal energy input. This result could open new possibilities for PWS catalyst design

Shedding of the Pandemic Swine-Origin Influenza A Virus (H1N1) after Oseltamivir Administration

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. We analyzed the virus shedding of an oseltamivir-treated patient who had been infected with the pandemic swine-origin influenza A (H1N1) virus which had an oseltamivir-sensitive neuraminidase. The virus was isolated from the pharyngeal swabs of the patient using MDCK cells, and the virus genome RNA was detected in the same samples both by real-time RT-PCR and RT-PCR. The virus was isolated until 44 h after oseltamivir administration although the virus genome was detected until one day after oseltamivir treatment was stopped. Due to their high sensitivity, RT-PCR and real-time RT-PCR may cause misdiagnosis by detection of viral genome which does not infect, and classical virus isolation and clinical symptoms are recommended for the evaluation of oseltamivir treatment. 1

Shedding of the Pandemic Swine-Origin Influenza A Virus (H1N1) after Oseltamivir Administration

International audienceWe analyzed the virus shedding of an oseltamivir-treated patient who had been infected with the pandemic swine-origin influenza A (H1N1) virus which had an oseltamivir-sensitive neuraminidase. The virus was isolated from the pharyngeal swabs of the patient using MDCK cells, and the virus genome RNA was detected in the same samples both by real-time RT-PCR and RTPCR. The virus was isolated until 44 h after oseltamivir administration although the virus genome was detected until one day after oseltamivir treatment was stopped. Due to their high sensitivity, RT-PCR and real-time RT-PCR may cause misdiagnosis by detection of viral genome which does not infect, and classical virus isolation and clinical symptoms are recommended for the evaluation of oseltamivir treatment