QUANTIFICATION OF MYOCARDIAL MECHANICS IN LEFT VENTRICLES UNDER INOTROPIC STIMULATION AND IN HEALTHY RIGHT VENTRICLES USING 3D DENSE CMR

Statistical data from clinical studies indicate that the death rate caused by heart disease has decreased due to an increased use of evidence-based medical therapies. This includes the use of magnetic resonance imaging (MRI), which is one of the most common non-invasive approaches in evidence-based health care research. In the current work, I present 3D Lagrangian strains and torsion in the left ventricle of healthy and isoproterenol-stimulated rats, which were investigated using Displacement ENcoding with Stimulated Echoes (DENSE) cardiac magnetic resonance (CMR) imaging. With the implementation of the 12-segment model, a detailed profile of regional cardiac mechanics was reconstructed for each subject. Statistical analysis revealed that isoproterenol induced a significant change in the strains and torsion in certain regions at the mid-ventricle level. In addition, I investigated right ventricular cardiac mechanics with the methodologies developed for the left ventricle. This included a comparison of different regions within the basal and mid-ventricular regions. Despite no regional variation found in the peak circumferential strain, the peak longitudinal strain exhibited regional variation at the anterior side of the RV due to the differences in biventricular torsion, mechanism of RV free wall contraction, and fiber architecture at RV insertions. Future applications of the experimental work presented here include the construction and validation of biventricular finite element models. Specifically, the strains predicted by the models will be statistically compared with experimental strains. In addition, the results of the present study provide an essential reference of RV baseline evaluated with DENSE MRI, a highly objective technique

Non-local Attention Optimized Deep Image Compression

This paper proposes a novel Non-Local Attention Optimized Deep Image Compression (NLAIC) framework, which is built on top of the popular variational auto-encoder (VAE) structure. Our NLAIC framework embeds non-local operations in the encoders and decoders for both image and latent feature probability information (known as hyperprior) to capture both local and global correlations, and apply attention mechanism to generate masks that are used to weigh the features for the image and hyperprior, which implicitly adapt bit allocation for different features based on their importance. Furthermore, both hyperpriors and spatial-channel neighbors of the latent features are used to improve entropy coding. The proposed model outperforms the existing methods on Kodak dataset, including learned (e.g., Balle2019, Balle2018) and conventional (e.g., BPG, JPEG2000, JPEG) image compression methods, for both PSNR and MS-SSIM distortion metrics

Prevalence of Kaposi’s sarcoma-associated herpesvirus in Uygur and Han populations from the Urumqi and Kashgar regions of Xinjiang, China

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the infectious etiologic agent associated with Kaposi’s sarcoma (KS), primary effusion lymphoma, and multicentric Castleman disease. It has been shown that high KSHV prevalence and high incidence of both classic KS and AIDSassociated KS are found mostly among people of Uygur ethnicity in Xinjiang, while people of Han ethnicity in Xinjiang have a higher KSHV seroprevalence than those of other Han populations in mainland China. However, it is still unclear why there is such geographical and population variation in KSHV distribution in China. In this work, we focused on the populations in the Kashgar region and Urumqi area, where a total of 1294 research subjects were randomly selected to investigate the potential correlation between KSHV prevalence and different ethnicities in endemic areas of Xinjiang, and to determine risk factors that may affect KSHV infection rates or KS incidence. We identified a high seroprevalence of KSHV and high peripheral blood DNA infection in the general Uygur and Han populations in both Urumqi and Kashgar regions of Xinjiang, and determined that advancing age, low education level, and stationary population status affect KSHV infection rates. Further, KSHV-positive Uygur participants were shown to have higher prevalence of neutralizing antibodies and neutralizing antibody titers than KSHV-positive Han participants

Two Photon Decays of ηc\eta_c from Lattice QCD

We present an exploratory lattice study for the two-photon decay of $\eta_c$ using $N_f=2$ twisted mass lattice QCD gauge configurations generated by the European Twisted Mass Collaboration. Two different lattice spacings of $a=0.067$fm and $a=0.085$fm are used in the study, both of which are of physical size of 2$fm$. The decay widths are found to be $1.025(5)$KeV for the coarser lattice and $1.062(5)$KeV for the finer lattice respectively where the errors are purely statistical. A naive extrapolation towards the continuum limit yields $\Gamma\simeq 1.122(14)$KeV which is smaller than the previous quenched result and most of the current experimental results. Possible reasons are discussed.Comment: 13 pages, 7 figures; matches the published versio

Developing and validating a new comprehensive glucose-insulin pharmacokinetics and pharmacodynamics model

Type 2 diabetes has reached epidemic proportions worldwide. The resulting increase in chronic and costly diabetes related complications has potentially catastrophic implications for healthcare systems, and economics and societies as a whole. One of the key pathological factors leading to type 2 diabetes is insulin resistance (IR), which is the reduced or impaired ability of the body to make use of available insulin to maintain safe glucose concentrations in the bloodstream. It is essential to understand the physiology of glucose and insulin when investigating the underlying factors contributing to chronic diseases such as diabetes and cardiovascular disease. For many years, clinicians and researchers have been working to develop and use model-based methods to increase understanding and aid therapeutic decision support. However, the majority of practicable tests cannot yield more than basic metrics that allow only a threshold-based assessment of the underlying disorder. This thesis gives an overview on several dynamic model-based methodologies with different clinical applications in assessing glycaemia via measuring effects of treatment or medication on insulin sensitivity. Other tests are clinically focused, designed to screen populations and diagnose or detect the risk of developing diabetes. Thus, it is very important to observe sensitivity metrics in various clinical and research settings

Antiviral activity and mechanism of action of arbidol against Hantaan virus infection

Purpose: To investigate the activity and mechanism of action of arbidol against Hantaan virus (HTNV) activity by modulating inflammation via TLR-4 pathway.Methods: HUVEC cells infected with HTNV 76-118 were treated with serially diluted arbidol solutions at -2h (2 h before viral infection, pre-treatment mode), 0 h (at the same time as viral infection, simultaneous treatment mode) or 2 h (2 h after viral infection, post-treatment mode). The transcript levels of TLR4 were detected by semi-quantitative reverse transcription-PCR (RT-PCR) at 6, 12, 18, and 24 h later. The levels of iNOS and TNF-α were examined using enzyme-linked immunosorbent assay (ELISA).Results: Pre-treatment with arbidol, rather than simultaneous treatment or  post-treatment, effectively inhibited up-regulation of cellular TLR4 expression (up to 40 ± 6.1 % inhibition) and activity of supernatant iNOS induced by HTNV  infection(up to 44.1 ± 9.4 % inhibition), as well as in a LPSstimulated inflammatory endothelial cell. Arbidol decreased the elevated TNF-α levels induced by LPSstimulation.Conclusion: These results are the first evidence that arbidol modulates viral PRRs signaling and its consequential inflammatory cytokine/chemokine response during hantavirus infection.Keywords: Hantavirus, Arbidol, Toll-like receptors, inducible nitric oxide synthase, Antiviral activity, Inflammatio