A Simultaneous Safety Analysis of Crash Frequency and Severity for Highway-Rail Grade Crossings: The Competing Risks Method

This paper proposes a mathematical model, the competing risks method, to investigate highway-rail grade crossing (HRGC) crash frequency and crash severity simultaneously over a 30-year period. The proposed competing risks model is a special type of survival analysis to accommodate the competing nature of multiple outcomes from the same event of interest; in this case, the competing multiple outcomes are crash severities, while event of interest is crash occurrence. Knowledge-gain-based benefits to be discovered through the application of this model and 30-year dataset are as follows: (1) a straightforward and integrated one-step estimation process that considers both crash frequency and severity likelihood in the same model, so direct hazard ranking considering both crash frequency and severity likelihood is possible; (2) interpretative effects of identified covariates from both the direction and magnitude perspectives; and (3) the long-term cumulative effect of contributors with the cumulative incidence function.

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Application of the method of mathematical modeling for forecasting channel deformations at the underwater crossing of the main pipeline

SCIENCE & TECHNOLOGIES OIL AND OIL PRODUCTS PIPELINE TRANSPORTATION ◽

10.28999/2541-9595-2020-10-6-599-609 ◽

2020 ◽

Vol 10 (6) ◽

pp. 599-609

Author(s):

Valery А. Gruzdev ◽

◽

Georgy V. Mosolov ◽

Ekaterina A. Sabayda ◽

◽

...

Keyword(s):

Mathematical Modeling ◽

Mathematical Model ◽

Roughness Coefficient ◽

Computational Domain ◽

Channel Deformations ◽

Geological Surveys ◽

Kuban River ◽

The Stability ◽

Protective Structures

In order to determine the possibility of using the method of mathematical modeling for making long-term forecasts of channel deformations of trunk line underwater crossing (TLUC) through water obstacles, a methodology for performing and analyzing the results of mathematical modeling of channel deformations in the TLUC zone across the Kuban River is considered. Within the framework of the work, the following tasks were solved: 1) the format and composition of the initial data necessary for mathematical modeling were determined; 2) the procedure for assigning the boundaries of the computational domain of the model was considered, the computational domain was broken down into the computational grid, the zoning of the computational domain was performed by the value of the roughness coefficient; 3) the analysis of the results of modeling the water flow was carried out without taking the bottom deformations into account, as well as modeling the bottom deformations, the specifics of the verification and calibration calculations were determined to build a reliable mathematical model; 4) considered the possibility of using the method of mathematical modeling to check the stability of the bottom in the area of TLUC in the presence of man-made dumping or protective structure. It has been established that modeling the flow hydraulics and structure of currents, making short-term forecasts of local high-altitude reshaping of the bottom, determining the tendencies of erosion and accumulation of sediments upstream and downstream of protective structures are applicable for predicting channel deformations in the zone of the TLUC. In all these cases, it is mandatory to have materials from engineering-hydro-meteorological and engineering-geological surveys in an amount sufficient to compile a reliable mathematical model.

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Decision-Making With Long-Term Consequences: Temporal Discounting for Single and Multiple Outcomes in the Future.

10.21236/ada301353 ◽

1995 ◽

Author(s):

Mary K. Stevenson

Keyword(s):

Decision Making ◽

Temporal Discounting ◽

Multiple Outcomes ◽

The Future ◽

Long Term Consequences

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One-step synthesis of high-quality vanadium disulfide quantum dots for long-term lysosome-targetable imaging

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2021.130544 ◽

2021 ◽

pp. 130544

Author(s):

Dan Yang ◽

Liwen Chen ◽

Le Wang ◽

Zhongjie Cui ◽

Zhuoqi Wen ◽

...

Keyword(s):

Quantum Dots ◽

High Quality ◽

One Step

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Efficient Cryopreservation of Populus tremula by In Vitro-Grown Axillary Buds and Genetic Stability of Recovered Plants

Plants ◽

10.3390/plants10010077 ◽

2021 ◽

Vol 10 (1) ◽

pp. 77

Author(s):

Elena O. Vidyagina ◽

Nikolay N. Kharchenko ◽

Konstantin A. Shestibratov

Keyword(s):

Survival Rate ◽

Axillary Buds ◽

Long Term Storage ◽

Average Survival ◽

Transgenic Lines ◽

Ssr Loci ◽

One Step ◽

The One

Axillary buds of in vitro microshoots were successfully frozen at –196 °C by the one-step freezing method using the protective vitrification solution 2 (PVS2). Microshoots were taken from 11 transgenic lines and three wild type lines. Influence of different explant pretreatments were analyzed from the point of their influence towards recovery after cryopreservation. It was found out that the use of axillary buds as explants after removal of the apical one increases recovery on average by 8%. The cultivation on growth medium of higher density insignificantly raises the regenerants survival rate. Pretreatment of the osmotic fluid (OF) shows the greatest influence on the survival rate. It leads to the increase in survival rate by 20%. The cryopreservation technology providing regenerants average survival rate of 83% was developed. It was based on the experimental results obtained with explant pretreatment. Incubation time in liquid nitrogen did not affect the explants survival rate after thawing. After six months cryostorage of samples their genetic variability was analyzed. Six variable simple sequence repeat (SSR) loci were used to analyze genotype variability after the freezing-thawing procedure. The microsatellite analysis showed the genetic status identity of plants after cryopreservation and of the original genotypes. The presence of the recombinant gene in the transgenic lines after cryostorage were confirmed so as the interclonal variation in the growth rate under greenhouse conditions. The developed technique is recommended for long-term storage of various breeding and genetically modified lines of aspen plants, as it provides a high percentage of explants survival with no changes in genotype.

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One-Step Synthesis of Carbon Nanoparticles Capable of Long-Term Tracking Lipid Droplet for Real-Time Monitoring of Lipid Catabolism and Pharmacodynamic Evaluation of Lipid-Lowering Drugs

Analytical Chemistry ◽

10.1021/acs.analchem.1c00337 ◽

2021 ◽

Author(s):

Meng-Xian Liu ◽

Na Ding ◽

Shuai Chen ◽

Yong-Liang Yu ◽

Jian-Hua Wang

Keyword(s):

Real Time ◽

Lipid Droplet ◽

Carbon Nanoparticles ◽

Lipid Lowering ◽

Real Time Monitoring ◽

Lipid Catabolism ◽

Lipid Lowering Drugs ◽

One Step

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Dodecyl Mercaptan Functionalized Copper Mesh for Water Repellence and Oil-water Separation

Journal of Bionic Engineering ◽

10.1007/s42235-021-0062-7 ◽

2021 ◽

Vol 18 (4) ◽

pp. 887-899

Author(s):

Yanling Tian ◽

Jiekai Feng ◽

Zexin Cai ◽

Jiaqi Chao ◽

Dawei Zhang ◽

...

Keyword(s):

Separation Efficiency ◽

Synthesis Process ◽

Water Separation ◽

Oil Water Separation ◽

One Step ◽

Oil Water ◽

Water Repellence ◽

Copper Mesh ◽

Dodecyl Mercaptan

AbstractReckless discharge of industrial wastewater and domestic sewage as well as frequent leakage of crude oil have caused serious environmental problems and posed severe threat to human survival. Various nature inspired superhy-drophobic surfaces have been successfully applied in oily water remediation. However, further improvements are still urgently needed for practical application in terms of facile synthesis process and long-term durability towards harsh environment. Herein, we propose a simple one-step dodecyl mercaptan functionalization method to fabricate Super-hydrophobic-Superoleophilic Copper Mesh (SSCM). The prepared SSCM possesses excellent water repellence and oil affinity, enabling it to successfully separate various oil-water mixtures with high separation efficiency (e.g., > 99% for hexadecane-water mixture). The SSCM retains high separating ability when hot water and strong corrosive aqueous solutions are used to simulate oil-water mixtures, indicating remarkable chemical durability of the dodecyl mercaptan functionalized copper mesh. Additionally, the efficiency can be well maintained during 50 cycles of separation, and the water repellence is even stable after storage in air for 120 days, demonstrating the reusability and long-term stability of the SSCM. Furthermore, the functionalized mesh also shows good mechanical robustness towards abrasion by sandpaper, and oil-water separation efficiency of > 96% can be obtained after 10 cycles of abrasion. The reported one-step dodecyl mercaptan functionalization could be a simple method for increasing the water repellence of copper mesh, and thereby be a great candidate for treating large-scale oily wastewater in harsh environments.

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On the effect of antiresorptive drugs on the bone remodeling of the mandible after dental implantation: a mathematical model

Scientific Reports ◽

10.1038/s41598-021-82502-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mehran Ashrafi ◽

Farzan Ghalichi ◽

Behnam Mirzakouchaki ◽

Manuel Doblare

Keyword(s):

Mathematical Model ◽

Bone Density ◽

Bone Remodeling ◽

Dental Implants ◽

Implant Design ◽

Patient Specific ◽

Dental Implantation ◽

Antiresorptive Agents ◽

Antiresorptive Drugs

AbstractBone remodeling identifies the process of permanent bone change with new bone formation and old bone resorption. Understanding this process is essential in many applications, such as optimizing the treatment of diseases like osteoporosis, maintaining bone density in long-term periods of disuse, or assessing the long-term evolution of the bone surrounding prostheses after implantation. A particular case of study is the bone remodeling process after dental implantation. Despite the overall success of this type of implants, the increasing life expectancy in developed countries has boosted the demand for dental implants in patients with osteoporosis. Although several studies demonstrate a high success rate of dental implants in osteoporotic patients, it is also known that the healing time and the failure rate increase, necessitating the adoption of pharmacological measures to improve bone quality in those patients. However, the general efficacy of these antiresorptive drugs for osteoporotic patients is still controversial, requiring more experimental and clinical studies. In this work, we investigate the effect of different doses of several drugs, used nowadays in osteoporotic patients, on the evolution of bone density after dental implantation. With this aim, we use a pharmacokinetic–pharmacodynamic (PK/PD) mathematical model that includes the effect of antiresorptive drugs on the RANK/RANK-L/OPG pathway, as well as the mechano-chemical coupling with external mechanical loads. This mechano-PK/PD model is then used to analyze the evolution of bone in normal and osteoporotic mandibles after dental implantation with different drug dosages. We show that using antiresorptive agents such as bisphosphonates or denosumab increases bone density and the associated mechanical properties, but at the same time, it also increases bone brittleness. We conclude that, despite the many limitations of these very complex models, the one presented here is capable of predicting qualitatively the evolution of some of the main biological and chemical variables associated with the process of bone remodeling in patients receiving drugs for osteoporosis, so it could be used to optimize dental implant design and coating for osteoporotic patients, as well as the drug dosage protocol for patient-specific treatments.

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Large Gaps of Midline Abdominal Incisions and Their Management

The American Surgeon ◽

10.1177/000313480807401111 ◽

2008 ◽

Vol 74 (11) ◽

pp. 1094-1099

Author(s):

Mahmoud N. Kulaylat ◽

Constantine P. Karakousis

Keyword(s):

Abdominal Wall ◽

Surgical Procedures ◽

Skin Grafting ◽

Operative Management ◽

Full Thickness ◽

Tension Free ◽

Abdominal Malignancy ◽

One Step ◽

Short And Long Term

The operative management of midline full-thickness abdominal wall gaps is difficult, often requires several surgical procedures and is associated with significant short- and long-term complications. A rectus abdominis-posterior sheath (RAPS) flap with skin grafting provides a tension-free one-step repair which was used in three patients successfully with midline abdominal wall (including the skin) gaps who had multiple previous operations related to intra-abdominal malignancy. No complications occurred in these patients in relation to this procedure.

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