To procrastinate or not to procrastinate: A retrospective study of the optimal timing of containing the global spread of the COVID-19 pandemic

As global public health is under threat by the 2019-nCoV and a potential new wave of large-scale epidemic outbreak and spread is looming, an imminent question to ask is what the optimal strategy of epidemic prevention and control (P&C) measures would be, especially in terms of the timing of enforcing aggressive policy response so as to maximize health efficacy and to contain pandemic spread. Based on the current global pandemic statistic data, here we developed a logistic probability function configured SEIR model to analyse the COVID-19 outbreak and estimate its transmission pattern under different “anticipate- or delay-to-activate” policy response scenarios in containing the pandemic. We found that the potential positive effects of stringent pandemic P&C measures would be almost canceled out in case of significantly delayed action, whereas a partially procrastinatory wait-and-see control policy may still be able to contribute to containing the degree of epidemic spread although its effectiveness may be significantly compromised compared to a scenario of early intervention coupled with stringent P&C measures. A laissez-faire policy adopted by the government and health authority to tackling the uncertainly of COVID19-type pandemic development during the early stage of the outbreak turns out to be a high risk strategy from optimal control perspective, as significant damages would be produced as a consequence

Neuroproteomics and Systems Biology Approach to Identify Temporal Biomarker Changes Post Experimental Traumatic Brain Injury in Rats

Traumatic brain injury (TBI) represents a critical health problem of which diagnosis, management, and treatment remain challenging. TBI is a contributing factor in approximately one-third of all injury-related deaths in the United States. The Centers for Disease Control and Prevention estimate that 1.7 million people suffer a TBI in the United States annually. Efforts continue to focus on elucidating the complex molecular mechanisms underlying TBI pathophysiology and defining sensitive and specific biomarkers that can aid in improving patient management and care. Recently, the area of neuroproteomics-systems biology is proving to be a prominent tool in biomarker discovery for central nervous system injury and other neurological diseases. In this work, we employed the controlled cortical impact (CCI) model of experimental TBI in rat model to assess the temporal-global proteome changes after acute (1 day) and for the first time, subacute (7 days), post-injury time frame using the established cation-anion exchange chromatography-1D SDS gel electrophoresis LC-MS/MS platform for protein separation combined with discrete systems biology analyses to identify temporal biomarker changes related to this rat TBI model. Rather than focusing on any one individual molecular entity, we use

Ecological Civilisation Discourse in Xinhua’s African Newswires: Towards a Greener Agency?

How does Chinese central media represent Africa through its environmental news? This article argues that the way in which Chinese central media organisations have reported environmental issues across the African continent has altered from a reactive “charm defensive” towards the promotion of a developmental model: “Ecological Civilisation”. Based on a critical discourse analysis of headline African news published by the Xinhua News Agency, this research illustrates the emergence of this new, unexpected turn in Chinese representations of Africa, as well as highlighting the coherencies and tensions within this discourse. Questioning why this change in the emphasis of content has occurred, it investigates explanations at the macro-, mezzo-, and micro-levels of analysis, concluding that the evidence indicates that Xinhua’s content remains closely linked to the soft power goals of the Chinese Communist Party. However, the presence of risk discourses in some reports indicates that the hegemonic discourse is altering. This could potentially be the result of Xinhua’s own commercial objectives in Africa, or of the subjectivities of individual Xinhua journalists seeping into reports. This research provides significant contributions to an understanding of Chinese soft power in Africa, the ecology of Chinese media in Africa, and the development of environmental discourses

The Next Generation Virgo Cluster Survey - Infrared (NGVS-IR): I. A new Near-UV/Optical/Near-IR Globular Cluster selection tool

The NGVS-IR project (Next Generation Virgo Survey - Infrared) is a contiguous near-infrared imaging survey of the Virgo cluster of galaxies. It complements the optical wide-field survey of Virgo (NGVS). The current state of NGVS-IR consists of Ks-band imaging of 4 deg^2 centered on M87, and J and Ks-band imaging of 16 deg^2 covering the region between M49 and M87. In this paper, we present the observations of the central 4 deg^2 centered on Virgo's core region. The data were acquired with WIRCam on the Canada-France-Hawaii Telescope and the total integration time was 41 hours distributed in 34 contiguous tiles. A survey-specific strategy was designed to account for extended galaxies while still measuring accurate sky brightness within the survey area. The average 5\sigma limiting magnitude is Ks=24.4 AB mag and the 50% completeness limit is Ks=23.75 AB mag for point source detections, when using only images with better than 0.7" seeing (median seeing 0.54"). Star clusters are marginally resolved in these image stacks, and Virgo galaxies with \mu_Ks=24.4 AB mag arcsec^-2 are detected. Combining the Ks data with optical and ultraviolet data, we build the uiK color-color diagram which allows a very clean color-based selection of globular clusters in Virgo. This diagnostic plot will provide reliable globular cluster candidates for spectroscopic follow-up campaigns needed to continue the exploration of Virgo's photometric and kinematic sub-structures, and will help the design of future searches for globular clusters in extragalactic systems. Equipped with this powerful new tool, future NGVS-IR investigations based on the uiK diagram will address the mapping and analysis of extended structures and compact stellar systems in and around Virgo galaxies.Comment: 23 pages, 18 figures. Accepted for publication in ApJ

An approach for the identification of targets specific to bone metastasis using cancer genes interactome and gene ontology analysis

Metastasis is one of the most enigmatic aspects of cancer pathogenesis and is a major cause of cancer-associated mortality. Secondary bone cancer (SBC) is a complex disease caused by metastasis of tumor cells from their primary site and is characterized by intricate interplay of molecular interactions. Identification of targets for multifactorial diseases such as SBC, the most frequent complication of breast and prostate cancers, is a challenge. Towards achieving our aim of identification of targets specific to SBC, we constructed a 'Cancer Genes Network', a representative protein interactome of cancer genes. Using graph theoretical methods, we obtained a set of key genes that are relevant for generic mechanisms of cancers and have a role in biological essentiality. We also compiled a curated dataset of 391 SBC genes from published literature which serves as a basis of ontological correlates of secondary bone cancer. Building on these results, we implement a strategy based on generic cancer genes, SBC genes and gene ontology enrichment method, to obtain a set of targets that are specific to bone metastasis. Through this study, we present an approach for probing one of the major complications in cancers, namely, metastasis. The results on genes that play generic roles in cancer phenotype, obtained by network analysis of 'Cancer Genes Network', have broader implications in understanding the role of molecular regulators in mechanisms of cancers. Specifically, our study provides a set of potential targets that are of ontological and regulatory relevance to secondary bone cancer.Comment: 54 pages (19 pages main text; 11 Figures; 26 pages of supplementary information). Revised after critical reviews. Accepted for Publication in PLoS ON

Comparison of Standard Ruler and Standard Candle constraints on Dark Energy Models

We compare the dark energy model constraints obtained by using recent standard ruler data (Baryon Acoustic Oscillations (BAO) at z=0.2 and z=0.35 and Cosmic Microwave Background (CMB) shift parameters R and l_a) with the corresponding constraints obtained by using recent Type Ia Supernovae (SnIa) standard candle data (ESSENCE+SNLS+HST from Davis et. al.). We find that, even though both classes of data are consistent with LCDM at the 2\sigma level, there is a systematic difference between the two classes of data. In particular, we find that for practically all values of the parameters (\Omega_0m,\Omega_b) in the 2\sigma range of the the 3-year WMAP data (WMAP3) best fit, LCDM is significantly more consistent with the SnIa data than with the CMB+BAO data. For example for (\Omega_0m,\Omega_b)=(0.24,0.042) corresponding to the best fit values of WMAP3, the dark energy equation of state parametrization w(z)=w_0 + w_1 (z/(1+z)) best fit is at a 0.5\sigma distance from LCDM (w_0=-1,w_1=0) using the SnIa data and 1.7\sigma away from LCDM using the CMB+BAO data. There is a similar trend in the earlier data (SNLS vs CMB+BAO at z=0.35). This trend is such that the standard ruler CMB+BAO data show a mild preference for crossing of the phantom divide line w=-1, while the recent SnIa data favor LCDM. Despite of this mild difference in trends, we find no statistically significant evidence for violation of the cosmic distance duality relation \eta \equiv d_L(z)/(d_A(z) (1+z)^2)=1. For example, using a prior of \Omega_0m=0.24, we find \eta=0.95 \pm 0.025 in the redshift range 0<z<2, which is consistent with distance duality at the 2\sigma level.Comment: References added. 9 pages, 7 figures. The Mathematica files with the numerical analysis of the paper can be found at http://leandros.physics.uoi.gr/rulcand/rulcand.ht

Lost in Translation? Accountability and Governance of Clinical Stem Cell Research in China

Despite China’s regulatory initiatives to promote its research accountability, it still needs to prove itself as a trusted player in life science research. In addition, in contrast to its huge investment, China is losing the race in delivering quality application of stem cells. The trial implementation of the 2015 ministerial regulations seemed to offer hope in ending this dual ‘lost-in-translation’. Yet skepticism remains. By examining China’s regulatory trajectory in the last 15 years, this paper illustrates that it is a post-hoc pragmatic policy rationale and a soft centralisation regulatory approach that have hampered China’s governance. To improve China’s governance of accountability, policy-makers need to get beyond an ‘act-in-response’ regulatory ethos and engage with diverse stakeholders

Myocardial production and release of MCP-1 and SDF-1 following myocardial infarction: differences between mice and man

<p>Abstract</p> <p>Background</p> <p>Stem cell homing to the heart is mediated by the release of chemo-attractant cytokines. Stromal derived factor -1 alpha (SDF-1a) and monocyte chemotactic factor 1(MCP-1) are detectable in peripheral blood after myocardial infarction (MI). It remains unknown if they are produced by, and released from, the heart in order to attract stem cells to repair the damaged myocardium.</p> <p>Methods</p> <p>Murine hearts were studied for expression of MCP-1 and SDF-1a at day 3 and day 28 following myocardial infarction to determine whether production is increased following MI. In addition, we studied the coronary artery and coronary sinus (venous) blood from patients with normal coronary arteries, stable coronary artery disease (CAD), unstable angina and MI to determine whether these cytokines are released from the heart into the systemic circulation following MI.</p> <p>Results</p> <p>Both MCP-1 and SDF-1a are constitutively produced and released by the heart. MCP-1 mRNA is upregulated following murine experimental MI, but SDF-1a is suppressed. There is less release of SDF-1a into the systemic circulation in patients with all stages of CAD including MI, mimicking the animal model. However MCP-1 release from the human heart following MI is also suppressed, which is the exact opposite of the animal model.</p> <p>Conclusions</p> <p>SDF-1a and MCP-1 release from the human heart are suppressed following MI. In the case of SDF-1a, the animal model appropriately reflects the human situation. However, for MCP-1 the animal model is the exact opposite of the human condition. Human observational studies like this one are paramount in guiding translation from experimental studies to clinical trials.</p

In Silico and In Vitro Investigations of the Mutability of Disease-Causing Missense Mutation Sites in Spermine Synthase

Spermine synthase (SMS) is a key enzyme controlling the concentration of spermidine and spermine in the cell. The importance of SMS is manifested by the fact that single missense mutations were found to cause Snyder-Robinson Syndrome (SRS). At the same time, currently there are no non-synonymous single nucleoside polymorphisms, nsSNPs (harmless mutations), found in SMS, which may imply that the SMS does not tolerate amino acid substitutions, i.e. is not mutable.To investigate the mutability of the SMS, we carried out in silico analysis and in vitro experiments of the effects of amino acid substitutions at the missense mutation sites (G56, V132 and I150) that have been shown to cause SRS. Our investigation showed that the mutation sites have different degree of mutability depending on their structural micro-environment and involvement in the function and structural integrity of the SMS. It was found that the I150 site does not tolerate any mutation, while V132, despite its key position at the interface of SMS dimer, is quite mutable. The G56 site is in the middle of the spectra, but still quite sensitive to charge residue replacement.The performed analysis showed that mutability depends on the detail of the structural and functional factors and cannot be predicted based on conservation of wild type properties alone. Also, harmless nsSNPs can be expected to occur even at sites at which missense mutations were found to cause diseases

X-ray Properties of the First SZE-selected Galaxy Cluster Sample from the South Pole Telescope

We present results of X-ray observations of a sample of 15 clusters selected via their imprint on the cosmic microwave background (CMB) from the thermal Sunyaev-Zel'dovich (SZ) effect. These clusters are a subset of the first SZ-selected cluster catalog, obtained from observations of 178 deg^2 of sky surveyed by the South Pole Telescope. Using X-ray observations with Chandra and XMM-Newton, we estimate the temperature, T_X, and mass, M_g, of the intracluster medium (ICM) within r_500 for each cluster. From these, we calculate Y_X=M_g T_X and estimate the total cluster mass using a M_500-Y_X scaling relation measured from previous X-ray studies. The integrated Comptonization, Y_SZ, is derived from the SZ measurements, using additional information from the X-ray measured gas density profiles and a universal temperature profile. We calculate scaling relations between the X-ray and SZ observables, and find results generally consistent with other measurements and the expectations from simple self-similar behavior. Specifically, we fit a Y_SZ-Y_X relation and find a normalization of 0.82 +- 0.07, marginally consistent with the predicted ratio of Y_SZ/Y_X=0.91+-0.01 that would be expected from the density and temperature models used in this work. Using the Y_X derived mass estimates, we fit a Y_SZ-M_500 relation and find a slope consistent with the self-similar expectation of Y_SZ ~ M^5/3 with a normalization consistent with predictions from other X-ray studies. We compare the X-ray mass estimates to previously published SZ mass estimates derived from cosmological simulations of the SPT survey. We find that the SZ mass estimates are lower by a factor of 0.89+-0.06, which is within the ~15% systematic uncertainty quoted for the simulation-based SZ masses.Comment: 28 pages, 19 figures, submitted to Ap