60 research outputs found

    Simulations of Disordered Matter in 3D with the Morphological Autoregressive Protocol (MAP) and Convolutional Neural Networks

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    Disordered molecular systems such as amorphous catalysts, organic thin films, electrolyte solutions, and water are at the cutting edge of computational exploration today. Traditional simulations of such systems at length-scales relevant to experiments in practice require a compromise between model accuracy and quality of sampling. To remedy the situation, we have developed an approach based on generative machine learning called the Morphological Autoregressive Protocol (MAP) which provides computational access to mesoscale disordered molecular configurations at linear cost at generation for materials in which structural correlations decay sufficiently rapidly. The algorithm is implemented using an augmented PixelCNN deep learning architecture that we previously demonstrated produces excellent results in 2 dimensions (2D) for mono-elemental molecular systems. Here, we extend our implementation to multielemental 3D and demonstrate performance using water as our test system in two scenarios: 1. liquid water, and 2. a sample conditioned on the presence of a rare motif. We trained the model on small-scale samples of liquid water produced using path-integral molecular dynamics simulation including nuclear quantum effects under ambient conditions. MAP-generated water configurations are shown to accurately reproduce the properties of the training set and to produce stable trajectories when used as initial conditions in classical and quantum dynamical simulations. We expect our approach to perform equally well on other disordered molecular systems while offering unique advantages in situations when the disorder is quenched rather than equilibrated

    Antimicrobial peptides of the vaginal innate immunity and their role in the fight against sexually transmitted diseases

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    Some antimicrobial peptides (AMPs) are produced in the vaginal innate immune system and play an important role in protecting this organ against pathogenic agents. Moreover, sexually transmitted diseases have become a major problem in human societies and are rapidly spreading. The emergence of antibiotic-resistant microbes (superbugs) can pose a major threat to human societies and cause rapid spread of these diseases. Finding new antimicrobial compounds to fight superbugs is therefore essential. It has been shown that AMPs have good potential to become new antibiotics. The most important AMPs in the vaginal innate immune system are defensins, secretory leucocyte protease inhibitors, calprotectin, lysozyme, lactoferrin and elafin, which play an important role in host defence against sexually transmitted infections, modulation of immune responses and anticancer activities. Some AMPs, such as LL-37, magainin 2 and nisin, show both spermicidal and antimicrobial effects in the vagina. In this summary, we will discuss vaginal AMPs and continue to address some of the challenges of using peptides to control pathogens that are effective in sexually transmitted diseases. © 2019 The Author(s

    Study and Research on the Six-Year Process of Bitcoin Price and Return

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    The purpose of this study, is create a challenge and discussion concerning the existence of information about the Bitcoin price and return, which suggests the relationship of information and the strong performance it. The information trends are available at different time periods and the summary data related to the statistical descriptions for the price and return index are also discussed. In this paper we show a significant correlation between the price trend and return in the Bitcoin that has been confirmed by various statistical methodology. Using statistical tests and reviewing trends and relationships between the variables, planning can be done to invest in it and its performance or inefficiency can be tested. The results of this research shows a significant and positive relationship between the price and return of Bitcoin

    The Test of the Effect of Investor Trading Behavior and Investors` Sentiment on Excess Return in Tehran Stock Exchange

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    How the behavioral pattern and investors` sentiment affect excess return is one of the challenges of today behavioral financial. The finance literature shows that a large part of the excess stock returns is not easily explained by fundamental factors. The purpose of this study is to investigate the effect of investors` sentiment index and volume of stoke traded to explain stock excess returns in Tehran stock exchange. In this study, an attempt was made to use the data of 155 companies listed in Tehran Stock Exchange during the period 2011-2015. Regressions were used to examine the effect of the trading behavior of investors, investor’s sentiment on the excess return. The results show that the trading behavior of investors has effects on the value of assets (excess return) and investors` sentiment affects the value of assets

    A comparative analysis of ceramic and cemented carbide end mills

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    Milling of ferrous metals is usually performed by applying cemented carbide tools due to their high hardness, temperature and wear resistance. Recently, ceramic tool materials have been on the rise and enhanced the efficiency in machining. As ceramics are brittle-hard materials, tool manufacturing requires a sound knowledge in order to meet the tool requirements such as sharp cutting edges and wear resistance. In this study, milling tools made of the high performance ceramic SiAlON were compared to tools made from cemented carbide. For both tool materials, the influence of a prepared cutting edge was investigated. Both the tool manufacturing process and the cutting edge preparation processes are presented, followed by the application of those tools within milling experiments. In order to evaluate the efficiency of both tool types, the cutting forces and the cumulative process energy demand were analyzed. Additionally, surface roughness of the machined workpieces and tool wear were examined. It was found that the ceramic tools, although process forces were higher than for cemented carbide tools, exhibited by far lower energy consumption, less tool wear and finally generated lower surface roughness. © 2020, The Author(s)

    B Cell Epitopes of Four Fimbriae Antigens of Klebsiella pneumoniae: A Comprehensive In Silico Study for Vaccine Development

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    Klebsiella pneumoniae is one of the major causes of nosocomial infections worldwide which can cause several diseases in children and adults. The globally dissemination of hyper-virulent strains of K. pneumoniae and the emergence of antibiotics-resistant isolates of this pathogen narrows down the treatment options and has renewed interest in its vaccines. Vaccine candidates of Klebsiella pneumoniae have not been adequately protective, safe and globally available yet. In K. pneumoniae infection, it is well known that B cells that induce robust humoral immunity are necessary for the host complete protection. Identifying the B cell epitopes of antigens is valuable to design novel vaccine candidates. In the present study using immunoinformatics approaches we found B cell epitopes of four K. pneumoniae type 1 fimbriae antigens namely FimA, FimF, FimG, and FimH. Linear and conformational B cell epitopes of each antigen were predicted using different programs. Subsequently, many bioinformatics assays were applied to choose the best epitopes including prediction antigenicity, toxicity, human similarity and investigation on experimental records. These assays resulted in final four epitopes (each for one Fim protein). These final epitopes were modeled and their physiochemical properties were estimated to be used as potential vaccine candidates. Altogether, we found four B cell epitopes of K. pneumoniae Fim antigens that are immunogen, antigenic, not similar to human peptides, not allergen and not toxic. Also, they have suitable physiochemical properties to administrate as vaccine, although their complete efficacy should be also shown in vitro and in vivo. © 2020, Springer Nature B.V

    Diagnoses and clinical features associated with high risk for unplanned readmission in vascular surgery. A cohort study

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    Background: Readmission rate is an established health quality indicator. Preventable readmissions bear an unnecessary, high cost on the healthcare system. An analysis performed by the National Centre for Health Outcomes Development (NCHOD) has demonstrated an increasing trend in emergency readmissions in the UK. Vascular surgery has been reported to have high readmission rates second only to congestive heart failure. This study aims to identify diagnoses and other clinical risk factors for high unplanned readmission rates. This may be the first step to sparing both the health care system and patients of unnecessary readmissions. Results: The overall 30 day readmission rate for Leeds Vascular Institute was 8.8%. The two diagnoses with the highest readmission rates were lower limb ischaemia and diabetic foot sepsis. The readmission rate for medical reasons was overwhelmingly higher than for surgical reasons (6.5% and 2.3% respectively). The most common medical diagnoses were renal disease and COPD. The majority of the patients readmitted under the care of vascular surgery required further surgical treatment. Conclusion: Vascular units should focus on holistic and multidisciplinary treatment of lower limb ischaemia and diabetic foot sepsis, in order to prevent readmissions. Furthermore, the early involvement and input of physicians in the treatment of vascular patients with renal disease and COPD may be appropriate

    Treatment of coronary lesions with a novel crystalline sirolimus-coated balloon

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    BackgroundThere is mounting data supporting the use of drug-coated balloons (DCB) not only for treatment of in-stent restenosis (ISR), but also in native coronary artery disease. So far, paclitaxel-coated balloons represented the mainstay DCBs. The SeQuent® crystalline sirolimus-coated balloon (SCB) (B.Braun Medical Inc, Germany) represents a novel DCB, which allows a sustained release of the limus-drug. We evaluated its performance in an all-comer cohort, including complex coronary lesions.MethodsConsecutive patients treated with the SeQuent® SCB were analyzed from the prospective SIROOP registry (NCT04988685). We assessed clinical outcomes, including major adverse cardiovascular events (MACE), target lesion revascularization (TLR), target vessel myocardial infarction (TV-MI) and cardiovascular death. Angiograms and outcomes were independently adjudicated.ResultsFrom March 2021 to March 2023, we enrolled 126 patients and lesions, of which 100 (79%) treated using a “DCB-only” strategy and 26 (21%) with a hybrid approach (DES + DCB). The mean age was 68 ± 10 years, 48 (38%) patients had an acute coronary syndrome. Regarding lesion characteristics, ISR was treated in 27 (21%), 11 (9%) underwent CTO-PCI and 59 (47%) of the vessels were moderate to severe calcified. Procedural success rate was 100%. At a median follow-up time of 12.7 (IQR 12; 14.2) months, MACE occurred in 5 patients (4.3%). No acute vessel closure was observed.ConclusionsOur data indicates promising outcomes following treatment with this novel crystalline SCB in an all-comer cohort with complex coronary lesions. These results require further investigation with randomized trials

    Non-linear Autoregressive Neural Networks to Forecast Short-Term Solar Radiation for Photovoltaic Energy Predictions

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    Nowadays, green energy is considered as a viable solution to hinder CO2 emissions and greenhouse effects. Indeed, it is expected that Renewable Energy Sources (RES) will cover 40% of the total energy request by 2040. This will move forward decentralized and cooperative power distribution systems also called smart grids. Among RES, solar energy will play a crucial role. However, reliable models and tools are needed to forecast and estimate with a good accuracy the renewable energy production in short-term time periods. These tools will unlock new services for smart grid management. In this paper, we propose an innovative methodology for implementing two different non-linear autoregressive neural networks to forecast Global Horizontal Solar Irradiance (GHI) in short-term time periods (i.e. from future 15 to 120min). Both neural networks have been implemented, trained and validated exploiting a dataset consisting of four years of solar radiation values collected by a real weather station. We also present the experimental results discussing and comparing the accuracy of both neural networks. Then, the resulting GHI forecast is given as input to a Photovoltaic simulator to predict energy production in short-term time periods. Finally, we present the results of this Photovoltaic energy estimation discussing also their accuracy

    Metal free percutaneous coronary interventions in all-comers: First experience with a novel sirolimus-coated balloon

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    Background: Limus-eluting stents have become the mainstay for percutaneous coronary intervention (PCI). However, even with the latest generation drug-eluting stent, in-stent restenosis and very late stent thrombosis remain a concern. The Selution SLR™ drug-coated balloon (DCB) is a novel sirolimus-coated balloon that provides a controlled release of the antiproliferative drug. Herein is evaluated its performance in a real-world patient cohort with complex coronary artery lesions. Methods: Patients undergoing PCI using the Selution SLR™ DCB were analyzed from the prospective SIROOP registry. We evaluated procedural success and clinical outcomes, including major adverse cardiovascular event (MACE), cardiac death, target vessel myocardial infarction and target lesion revascularization. Results: From September 2020 to April 2021, we enrolled 78 patients (87 lesions) treated using a “DCB only” strategy. The mean age was 66.7 ± 10.4 years and 28 (36%) presented with an acute coronary syndrome. Almost all lesions were type B2/C 86 (99%) and 49 (63%) had moderate to severe calcifications. Procedural success was 100%. After a median follow-up of 11.2 months (interquartile range: 10.0–12.6), MACE occurred in 5 (6.8%) patients. No acute vessel closure was observed. Conclusions: In complex coronary lesions, a “DCB only” strategy using the Selution SLR™ DCB is not just safe and feasible, but also seems to be associated with a low rate of MACE at 1-year follow-up. Our promising results warrant further evaluation in a dedicated comparative trial
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