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Stability and scour development of bed material on crossbar block ramps

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International Journal of Sediment Research 2015年第04期30卷 344-350页

作者： Mario Oertel daniel b.bung Hydraulic Engineering Section Lbeck University of Applied Sciences Hydraulic Engineering Section Aachen University of Applied Sciences

block ramps are ecologically oriented drop structures with adequate energy dissipation and partially moderate flow velocities.A special case is given with crossbar block ramps,where the upstream and downstream level difference is reduced by a series of *** prevent the total structure from failing,the stability of single boulders within the crossbars and the bed material in between must be *** present paper addresses the stability of bed material and scour development for various flow *** bed material erosion may affect the stability of the crossbar boulders,which in turn can result in major damages of the *** new design approaches are developed to choose an appropriate bed material size and to avoid failures of crossbar block ramp structures.

关键词： Crossbar block ramp Scouring bed material erosion Particle densimetric Froude number

Mechanical circulatory support in cardiogenic shock and post-myocardial infarction mechanical complications

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Journal of Geriatric Cardiology 2022年第2期19卷 130-136页

作者： daniel Rob Jan bělohlávek nd Department of Medicine-Department of Cardiovascular Medicine First Faculty of MedicineCharles University and General University HospitalPragueCzech Republic

Despite advanced therapies,the mortality of patients with myocardial infarction(MI)complicated by cardiogenic shock(CS)remains around 50%.Mechanical complications of MI are rare nowadays but associated with high mortality in patients who present with *** treatment strategies and mechanical circulatory support(MCS)devices have been increasingly used to improve the grim prognosis of refractory *** article discusses current evidence regarding the use of MCS in MI complicated by CS,ventricular septal rupture,free wall rupture and acute mitral *** selection should be tailored according to the cause and severity of *** MCS initiation and multidisciplinary team cooperation is mandatory for good *** associated bleeding remains a major complication and an obstacle to better *** prospective randomized trials will improve current knowledge regarding MCS indications,timing,and patient selection in the coming years.

关键词： mortality infarction rupture

Design of synthetic materials for intracellular delivery of RNAs： From siRNA-mediated gene silencing to CRISPR/Cas gene editing

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Nano Research 2018年第10期11卷 5310-5337页

作者： Jason b. Miller daniel J. Siegwart Simmons Comprehensive Cancer Center University of Texas Southwestern Medical Center Dallas TX 75390 USA Department of biochemistry University of Texas Southwestern Medical Center Dallas TX 75390 USA

Ribonucleic acids （RNAs） possess great therapeutic potential and can be used to treat a variety of diseases. The unique biophysical properties of RNAs, such as high molecular weight, negative charge, hydrophilicity, low stability, and potential immunogenicity, require chemical modification and development of carriers to enable intracellular delivery of RNAs for clinical use. A variety of nanornaterials have been developed for the effective in vivo delivery of short/ small RNAs, messenger RNAs, and RNAs required for gene editing technologies including clustered regularly interspaced palindromic repeat （CRISPR）/Cas. This review outlines the challenges of delivering RNA therapeutics, explores the chemical synthesis of RNA modifications and carriers, and describes the efforts to design nanomaterials that can be used for a variety of clinical indications.

关键词： nucleic acid therapeutics nanoparticles synthetic nanomaterials RNA interference (RNAi) messenger RNA (mRNA) clustered regularly inter-spaced palindromic repeat(CRISPR)/Cas

Contributors’enrollment in collaborative online communities:the case of OpenStreetMap

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Geo-Spatial Information Science 2017年第3期20卷 282-295页

作者： daniel bégin Rodolphe Devillers Stéphane Roche Department of Geography Memorial University of NewfoundlandSt.John’sCanada Centre de Recherche en Géomatique UniversitéLavalQuébecCanada

The number of people registering in an online community depends on two main factors:interest in,and awareness of,the *** to a project does not,however,imply contributing to it,as lacking the knowledge and skills can be a barrier to *** order to identify the nature of events that might have facilitated or hindered enrollments in the OpenStreetMap(OSM)project over time,we analyzed the correlations between the number of new participants and the events that dotted its *** different metrics were defined to characterize participants’behaviors:the daily number of registrations,the daily number of participants that made a first contribution,the delays between contributors’registration and their first edits,and a daily contribution ratio built from the number of new contributors and the number of new registered *** series analyses were used to identify trends,and outstanding variations of the number of *** inventory of events that took place along the OSM project’s history was created and appreciable variations of the metrics have been linked to events that seemed to be *** a correlation does not imply causality,many of the explanations these correlations suggest are supported by the results of other studies,either directly or *** instance,when considering the time participants spend as“lurker”,as well as on the nature of the contribution of early *** other cases,they suggest new explanations for the origin of the spam accounts that affect registration statistics,or the decline in the proportion of registered members who actually become contributors.

关键词： OpenStreetMap(OSM) contributors lurkers participation knowledge motivation

Iron regulatory protein 1: the deadly switch of ferroptosis

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Neural Regeneration Research 2024年第3期19卷 477-478页

作者： daniel A.bórquez Pamela J.Urrutia Center for biomedical Research Faculty of MedicineUniversidad Diego PortalesSantiagoChile Institute of Nutrition&Food Technology(INTA) Universidad de ChileSantiagoChile Geroscience Center for brain Health and Metabolism SantiagoChile

Ferroptosis,an iron-dependent cell death:Ferroptosis is a type of regulated necrosis,characterized by redox-active iron accumulation and increased free radical production derived by Fenton chemistry,that triggers oxidation of polyunsaturated fatty acids in phospholipids,loss of cellular membranes integrity,and leakage of intracellular contents.

关键词： integrity switch Iron

A Light-Weight Deep Learning-based Architecture for Sign Language Classification

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Intelligent Automation & Soft Computing 2023年第3期35卷 3501-3515页

作者： M.daniel Nareshkumar b.Jaison Department of Electronics and Communication Engineering R.M.K.Engineering CollegeKavaraipettai601206India Department of Computer Science and Engineering R.M.K.Engineering CollegeKavaraipettai601206India

With advancements in computing powers and the overall quality of images captured on everyday cameras,a much wider range of possibilities has opened in various *** fact has several implications for deaf and dumb people as they have a chance to communicate with a greater number of people much *** than ever before,there is a plethora of info about sign language usage in the real *** languages,and by extension the datasets available,are of two forms,isolated sign language and continuous sign *** main difference between the two types is that in isolated sign language,the hand signs cover individual letters of the *** continuous sign language,entire words’hand signs are *** paper will explore a novel deep learning architecture that will use recently published large pre-trained image models to quickly and accurately recognize the alphabets in the American Sign Language(ASL).The study will focus on isolated sign language to demonstrate that it is possible to achieve a high level of classiﬁcation accuracy on the data,thereby showing that interpreters can be implemented in the real *** newly proposed Mobile-NetV2 architecture serves as the backbone of this *** is designed to run on end devices like mobile phones and infer signals(what does it infer)from images in a relatively short amount of *** the proposed architecture in this paper,the classiﬁcation accuracy of 98.77%in the Indian Sign Language(ISL)and American Sign Language(ASL)is achieved,outperforming the existing state-of-the-art systems.

关键词： Deep learning machine learning classiﬁcation ﬁlters american sign language

A Meshless Regularization Method for a Two-Dimensional Two-Phase Linear Inverse Stefan Problem

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Advances in Applied Mathematics and Mechanics 2013年第6期5卷 825-845页

作者： b.Tomas Johansson daniel Lesnic Thomas Reeve Department of Science and Technology Campus Norrk¨opingLink¨oping UniversitySweden Department of AppliedMathematics University of LeedsLeeds LS29JTUK School of Mathematics University of BirminghamBirmingham B152TTUK

In this paper,a meshless regularization method of fundamental solutions is proposed for a two-dimensional,two-phase linear inverse Stefan *** numerical implementation and analysis are challenging since one needs to handle composite materials in higher ***,the inverse Stefan problem is ill-posed since small errors in the input data cause large errors in the desired output ***,regularization is necessary in order to obtain a stable *** results for several benchmark test examples are presented and discussed.

关键词： Heat conduction method of fundamental solutions(MFS) inverse Stefan problem two-phase change

bone-conditioned medium contributes to initiation and progression of osteogenesis by exhibiting synergistic TGF-β1/bMP-2 activity

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International Journal of Oral Science 2018年第4期10卷 203-211页

作者： Maria b.Asparuhova Jordi Caballé-Serrano daniel buser Vivianne Chappuis Laboratory of Oral Cell biology School of Dental MedicineUniversity of Bern Department of Oral Surgery and Stomatology School of Dental MedicineUniversity of Bern Department of Oral and Maxillofacial Surgery School of Dental MedicineUniversitat Internacional de Catalunya

Guided bone regeneration (GbR) often utilizes a combination of autologous bone grafts, deproteinized bovine bone mineral(DbbM), and collagen membranes. DbbM and collagen membranes pre-coated with bone-conditioned medium (bCM) extracted from locally harvested autologous bone chips have shown great regenerative potential in GbR. However, the underlying molecular mechanism remains largely unknown. Here, we investigated the composition of bCM and its activity on the osteogenic potential of mesenchymal stromal cells. We detected a fast and significant (P bone within 10 min versus a delayed bone morphogenetic protein-2 (bMP-2) release from 40 min onwards. bCMs harvested within short time periods (10, 20, or 40 min), corresponding to the time of a typical surgical procedure, significantly increased the proliferative activity and collagen matrix production of bCM-treated cells. Long-term (1, 3, or 6 days)-extracted bCMs promoted the later stages of osteoblast differentiation and maturation. Short-term-extracted bCMs, in which TGF-β1 but no bMP-2was detected, reduced the expression of the late differentiation marker osteocalcin. However, when both growth factors were present simultaneously in the bCM, no inhibitory effects on osteoblast differentiation were observed, suggesting a synergistic TGF-β1/bMP-2 activity. Consequently, in cells that were co-stimulated with recombinant TGF-β1 and bMP-2, we showed a significant stimulatory and dose-dependent effect of TGF-β1 on bMP-2-induced osteoblast differentiation due to prolonged bMP signaling and reduced expression of the bMP-2 antagonist noggin. Altogether, our data provide new insights into the molecular mechanisms underlying the favorable outcome from GbR procedures using bCM, derived from autologous bone grafts.

关键词： bone-conditioned medium contributes to initiation and progression of osteogenesis by exhibiting synergistic TGF bMP-2 activity

The role of extracorporeal life support and timing of repair in infants with congenital diaphragmatic hernia

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World Journal of Pediatric Surgery 2024年第2期7卷 90-99页

作者： daniel b Gehle Logan C Meyer Tim Jancelewicz Le bonheur Children's Hospital University of Tennessee Health Science CenterMemphisTennesseeUSA

Extracorporeal life support(ECLS)serves as a rescue therapy for patients with congenital diaphragmatic hernia(CDH)and severe cardiopulmonary failure,and only half of these patients survive to *** costly intervention has a significant complication risk and is reserved for patients with the most severe disease physiology refractory to maximal cardiopulmonary *** contraindications to ECLS do exist such as coagulopathy,lethal chromosomal or congenital anomaly,very preterm birth,or very low birth weight,but many of these limits are being evaluated through further *** guidelines from the past decade vary in recommendations for ECLS use in patients with CDH but this therapy appears to have a survival benefit in the most severe subset of *** outcomes have been observed for patients treated at high-volume *** review details the evolving literature surrounding management paradigms for timing of CDH repair for patients receiving preoperative *** recent data support early repair following cannulation to avoid non-repair which is uniformly fatal in this *** ECLS runs are associated with decreased survival,and patient physiology should guide ECLS weaning and eventual decannulation rather than limiting patients to arbitrary run *** of care across centers is a major focus to limit unnecessary costs and improve short-term and long-term outcomes for these complex patients.

关键词： congenital life repair