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Application of a Pulsed Electric Field to Modify the Free Energy of the Active Site of an Azoreductase

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Journal of Applied Mathematics and Physics 2024年第1期12卷 249-255页

作者： Jesus Magyber de Jesus Miranda Pedro Guillermo Reyes-Romero Jorge Mulia-Rodríguez daniel osorio-gonzález Molecular Biophysics Laboratory Faculty of Sciences Autonomous University of State of Mexico Toluca Mexico Advanced Physics Laboratory Faculty of Sciences Autonomous University of State of Mexico Toluca Mexico

The Gibbs free energy is strongly related to the stability and catalytic function of an enzyme through the energetic changes that occur in the chemical reactions the enzyme catalyzes. In this in silico study, a pulsed electric field was applied to an azoreductase, and its effect on the Gibbs free energy of molecular docking with two dyes was measured. We propose that certain stimuli from a pulsed electric field favor the structural stability of the enzyme by promoting an arrangement in the active site, potentially leading to an enhancement of enzymatic activity overall.

关键词： Pulsed Electric Field Molecular Dynamics Docking Azoreductase

Human Prion Protein Conformational Changes Susceptibility: A Molecular Dynamics Simulation Study

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Open Journal of Biophysics 2014年第4期4卷 169-175页

作者： Laura Alejandra Mandujano-Rosas daniel osorio-gonzález Pedro Guillermo Reyes-Romero Jorge Mulia-Rodríguez Laboratory of Molecular Biophysics Faculty of Sciences Autonomous University of State of Mexico Toluca Mexico Laboratory of Advaced Physics Faculty of Sciences Autonomous University of State of Mexico Toluca Mexico

Prion proteins are related to the development of incurable and invariably fatal neurodegenerative diseases in humans and animals. The pathogenicity involves the conversion of the host-encoded-alpha rich isoform of prion protein, PrPC, into a misfolded beta-strand rich conformer, PrPSc. Although it has already been described that many punctual mutations alter the stability of PrPC, making it more prone to adopt an abnormal misfolded structure, the majority of cases reported among general population are sporadic in wild-type organisms. Thus, in this work we studied the dynamics and stability profiles of wild-type human prion protein by Molecular Dynamics (MD) simulation at different solvent temperatures. This analysis brought out certain residues and segments of the prion protein as critical to conformational changes;these results are consistent with experimental reports showing that protein mutants in those positions are related to the development of disease.

关键词： Prion Protein Misfolding Susceptibility Molecular Dynamics Simulation

Predicting intensive care unit-acquired weakness:A multilayer perceptron neural network approach

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World Journal of Clinical Cases 2024年第12期12卷 2023-2030页

作者： Carlos Martin Ardila daniel gonzález-Arroyave Mateo Zuluaga-Gómez Department of Basic Sciences University of AntioquiaMedellín 52-59Colombia Department of Surgery Pontificia Universidad BolivarianaMedellín 0057Colombia Department of Emergency Universidad Pontificia BolivarianaMedellín 0057Colombia

In this editorial,we comment on the article by Wang and Long,published in a recent issue of the World Journal of Clinical Cases.The article addresses the challenge of predicting intensive care unit-acquired weakness(ICUAW),a neuromuscular disorder affecting critically ill patients,by employing a novel processing strategy based on repeated machine learning.The editorial presents a dataset comprising clinical,demographic,and laboratory variables from intensive care unit(ICU)patients and employs a multilayer perceptron neural network model to predict ICUAW.The authors also performed a feature importance analysis to identify the most relevant risk factors for ICUAW.This editorial contributes to the growing body of literature on predictive modeling in critical care,offering insights into the potential of machine learning approaches to improve patient outcomes and guide clinical decision-making in the ICU setting.

关键词： Intensive care units Intensive care unit-acquired weakness Risk factors Machine learning Computer neural network

Comprehensive review of hepatocellular carcinoma with portal vein tumor thrombus:State of art and future perspectives

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 221-227页

作者： Paschalis Gavriilidis Timothy M Pawlik daniel Azoulay Department of Surgery Colchester General HospitalTurner RoadColchester CO45JLUK Department of Surgery The Ohio State Wexner Medical CenterJames Comprehensive Cancer CenterColumbusOHUSA Department of Hepato-Biliary and Liver Transplantation surgery Paul Brousse University HospitalParis-Saclay UniversityVillejuif 94800France

Background:Despite advances in the diagnosis of patients with hepatocellular carcinoma(HCC),70%-80%of patients are diagnosed with advanced stage disease.Portal vein tumor thrombus(PVTT)is among the most ominous signs of advanced stage disease and has been associated with poor survival if untreated.Data sources:A systematic search of MEDLINE(PubMed),Embase,Cochrane Library and Database for Systematic Reviews(CDSR),Google Scholar,and National Institute for Health and Clinical Excellence(NICE)databases until December 2022 was conducted using free text and MeSH terms:hepatocellular carcinoma,portal vein tumor thrombus,portal vein thrombosis,vascular invasion,liver and/or hepatic resection,liver transplantation,and systematic review.Results:Centers of surgical excellence have reported promising results related to the individualized surgical management of portal thrombus versus arterial chemoembolization or systemic chemotherapy.Critical elements to the individualized surgical management of HCC and portal thrombus include precise classification of the portal vein tumor thrombus,accurate identification of the subgroups of patients who may benefit from resection,as well as meticulous surgical technique.This review addressed five specific areas:(a)formation of PVTT;(b)classifications of PVTT;(c)controversies related to clinical guidelines;(d)surgical treatments versus non-surgical approaches;and(e)characterization of surgical techniques correlated with classifications of PVTT.Conclusions:Current evidence from Chinese and Japanese high-volume centers demonstrated that patients with HCC and associated PVTT can be managed with surgical resection with acceptable results.

关键词： Hepatectomy Liver surgery Liver neoplasms Portal vein tumor thrombus

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Assessment of scale interactions associated with wake meandering using bispectral analysis methodologies

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 65-75页

作者： Dinesh Kumar Kinjangi daniel Foti Department of Mechanical Engineering University of MemphisMemphisTennesseeUSA

Large atmospheric boundary layer fluctuations and smaller turbine-scale vorticity dynamics are separately hypothesized to initiate the wind turbine wake meandering phenomenon,a coherent,dynamic,turbine-scale oscillation of the far wake.Triadic interactions,the mechanism of energy transfers between scales,manifest as triples of wavenumbers or frequencies and can be characterized through bispectral analyses.The bispectrum,which correlates the two frequencies to their sum,is calculated by two recently developed multi-dimensional modal decomposition methods:scale-specific energy transfer method and bispectral mode decomposition.Large-eddy simulation of a utility-scale wind turbine in an atmospheric boundary layer with a broad range of large length-scales is used to acquire instantaneous velocity snapshots.The bispectrum from both methods identifies prominent upwind and wake meandering interactions that create a broad range of energy scales including the wake meandering scale.The coherent kinetic energy associated with the interactions shows strong correlation between upwind scales and wake meandering.

关键词： Wind turbine wake Mode decomposition Bispectral analysis

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Testing and modelling of transient adhesion phenomena in rolling-sliding contacts

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Friction 2024年第5期12卷 1016-1027页

作者： daniel KVARDA Alexander MEIERHOFER Klaus SIX Faculty of Mechanical Engineering Brno University of TechnologyBrno61669Czech Republic Virtual Vehicle Research GmbH Graz8010Austria

Transient adhesion effects in rolling–sliding contacts influence all aspects of train–track interaction.This is of high importance specifically when these effects result in critically low adhesion,which poses a risk to traction and braking of railway vehicles.This study presents a model that can replicate the transient changes of the coefficient of adhesion with tested water and solid particle mix.The experimental data for the model are measured using a commercial ball-on-disc tribometer.The experimental results showed a liquid reservoir in front of the contact area that slowly reduces in size.This observation was used in the modelling approach to divide the calculation into two stages where the reservoir is present and when it disappears.The model was able to reproduce the occurrence of low adhesion region seen in experimental results with different particle concentrations.

关键词： coefficient of adhesion tribology transient effects wheel-rail contact

Rapid growth in a large Cambrian apex predator

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National Science Review 2024年第3期11卷 128-136页

作者：吴雨 Stephen Pates daniel Pauly 张兴亮傅东静 State Key Laboratory of Continental Dynamics and Shaanxi Key Laboratory of Early Life and Environment Department of Geology Northwest University Department of Zoology University of Cambridge Institute for the Oceans and Fisheries University of British Columbia Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

Despite the importance of ontogenetic data on early diverging euarthropods to our understanding of the ecology and evolution of past life, the data are distinctly lacking, as reconstructing life histories of fossil animals is often challenging. Here we report the growth trajectory of frontal appendages of the apex predator Amplectobelua symbrachiata, one of the most common radiodont arthropods from the early Cambrian Chengjiang biota(c. 520 Ma) of China. Analysis of 432 specimens(9.1–137.1 mm length; 1.3–25.6 mm height) reveals that appendages grew isometrically, with an estimated maximum size of the whole animal of c. 90 cm. Individuals grew rapidly compared to extant arthropods, as assessed using the electronic length-frequency analysis(ELEFAN) approach. Therefore, we show that the Cambrian apex predator A. symbrachiata was an extremely fast-growing arthropod, with an unusual life history strategy that formed as part of the escalatory ‘arms race’ that shaped the Cambrian explosion over 500 Ma.

关键词： stem-group Euarthropoda Radiodonta post-embryonic development growth dynamics Cambrian Explosion

Diagnosing upper tract urothelial carcinoma: A review of the role of diagnostic ureteroscopy and novel developments over last two decades

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Asian Journal of Urology 2024年第2期11卷 242-252页

作者： Paul Gravestock daniel Cullum Bhaskar Somani Rajan Veeratterapillay Urology Department Freeman HospitalNewcastle Upon TyneUK Department of Urology University Hospital SouthamptonSouthamptonUK

Objective: The role of ureteroscopy in the diagnosis of upper tract urothelial carcinoma is yet to be fully determined. We aimed to provide an up to date evaluation of its role and the emerging technologies in the field.Methods: A literature search of the last two decades (from 24th May, 2001 to 24th May, 2021) was carried out identifying 147 papers for potential inclusion within this narrative review.Results: Diagnostic ureteroscopy is undeniably useful in its ability to visualise and biopsy indeterminate lesions, and to risk stratify malignant lesions that may be suitable for kidney sparing surgery. However, an increased risk of intravesical recurrence following nephroureterectomy when a prior diagnostic ureteroscopy has been performed, inadequate sampling at biopsy, complications from the procedure, and difficult ureteric access are all potential drawbacks. Furthermore, whilst generally an accurate diagnostic procedure, it risks missing carcinoma in-situ lesions. Despite this, evidence shows that routine use of ureteroscopy changes the management of patients in a large proportion of cases, preventing unnecessary surgery or facilitating kidney sparing surgery. The overall rate of complications is low, and improved biopsy techniques and the use of tissue biomarkers for improved staging and grading are encouraging. The risks of delays to definitive management and post-ureteroscopy intravesical recurrence do not seem to affect survival, and trials are in progress to determine whether intravesical therapy can mitigate the latter. Further promising techniques are being investigated to improve shortcomings, particularly in relation to improved diagnosis of carcinoma in situ and preoperative staging.Conclusion: Ureteroscopy has a role in the diagnosis of upper tract malignancy, though whether it should be used routinely is yet to be determined.

关键词： Ureteroscopy Carcinoma Transitional cell Ureteralneoplasms Urinary bladder neoplasms Carcinomainsitu Biopsy

Online Demand Response Characterization Based on Variability in Customer Behavior

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 936-946页

作者： Lester Marrero daniel Sbárbaro Luis García-Santander the Department of Electrical Engineering University of Concepción IEEE

This paper proposes an online framework to characterize demand response(DR) over time. The proposed framework facilitates obtaining and updating the daily consumption patterns of customers. The essential concept of response profile class(RPC) is introduced for characterization and complemented by the measure of the variability in customer behavior. This paper uses a modified version of the incremental clustering by fast search and find of density peaks(CFSFDP) algorithm for daily profiles, considering the multivariate normal kernel density estimator and incremental forms of the Davies-Bouldin(i DB) and Xie-Beni(i XB) validity indices. Case studies conducted using real-world and simulated daily profiles of residential and commercial Chilean end-users have demonstrated how the proposed framework can continuously characterize DR. The proposed framework is proven to achieve realistic customer models for effective energy management by estimating the customer response to price signals at the distribution system operator(DSO) level.

关键词： Clustering algorithms Behavioral sciences Streams Pricing Feature extraction Monitoring Kernel