scholarly journals Evolution of bridges with steel-concrete composite superstructure. What comes next?

2021 ◽  
Author(s):  
Ciprian - Alin Farcas
Keyword(s):  
Composite Structures ◽  
Technological Progress ◽  
Structural System ◽  
Calculation Methods ◽  
Practical Applications ◽  
High Productivity ◽  
The Past ◽  
Complex Shapes ◽  
Different Types ◽  
Two Stages

Bridges have evolved over time from the simplest forms made from materials found in nature – wood and stone - to the complex shapes of today, made of concrete, steel, steel-concrete, and composite materials. If in the past the large dimensions of an obstacle impeded building a bridge, today this problem can be solved by choosing suitable materials, an advantageous structural system, and an erection method that favors the chosen solutions. The composite superstructures made of steel-concrete have started to be used more often in the construction of bridges due to their advantages. The scope of this paper is to analyze the evolution of road bridges with steel-concrete composite superstructure. There can be distinguished mainly 4 stages in the evolution of these types of structures. In the first two stages during 1850-1925 the connection between concrete and steel was achieved by the adhesion between the contact surfaces of the two materials. Starting with 1932 (stage III), a connection was realized that takes over the forces of friction that develop at the contact between the two materials. These connecting elements took different forms: loops the reinforcement, U, L, or ⊥ metal parts, shear stud connectors, and more recently composite dowels. The advantages of different types of connectors have been highlighted by various calculation methods, practical applications, and high productivity. Nowadays the construction of an impressive bridge has become a source of pride at an international level, a way to demonstrate the technological progress in the field. But what does the future hold in the field of composite structures made of steel-concrete?

scholarly journals WATER DISCHARGE MEASURING INSTRUMENTS: AN UP TO DATE OVERVIEW

2021 ◽  
Vol 3 ◽  
pp. 116-123
Author(s):  
Artem Iukhno ◽  
Sergei Buzmakov ◽  
Alisa Zorina
Keyword(s):  
Technological Progress ◽  
Water Discharge ◽  
Channel Width ◽  
Measuring Instruments ◽  
Management Decisions ◽  
The Past ◽  
Different Types ◽  
Analytical Review ◽  
New Instruments

Technological progress could not but affect the sphere of hydrometric measurements. New instruments have been implemented to add to such traditional measuring instruments as mechanical current meters or to replace them. Over the past 20 years, the number of different types measuring instruments has increased dramatically. That is why the analytical review and classification of these devices are needed to help with making appropriate management decisions in the field of streamflow monitoring and surveys. The article presents the multivariable classification of measuring instruments, based on such factors as: morphology scaling (channel width and depth), measuring conditions (open, weed or ice-covered channel), logistical factor (mobile or stationary) and required accuracy. Characteristics of each type of measuring instruments were also considered and the limitations of their applicability were described. The results presented in the paper are expected to expand the horizons of approaches used for estimation of water discharge.

Study of the Molecular Architecture of Keratin Filaments by Electron Microscopy

1982 ◽  
Vol 40 ◽  
pp. 118-119
Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun
Keyword(s):  
Electron Microscopy ◽  
Structural Organization ◽  
Cell Types ◽  
Structural Features ◽  
Molecular Architecture ◽  
The Past ◽  
Keratin Filaments ◽  
Different Types ◽  
10 Nm Filaments ◽  
Different Cell Types

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.

Is Healthcare Special?

2018 ◽  
Author(s):  
Gordon Moore ◽  
John A. Quelch ◽  
Emily Boudreau
Keyword(s):  
Consumer Choice ◽  
Special Relationship ◽  
Individual Choice ◽  
Health Consequences ◽  
Critical Question ◽  
The Past ◽  
Different Types ◽  
Collective Benefit ◽  
Patient Ethics

Chapter 2 asks the critical question of whether healthcare is different from other consumer-driven markets. In the past, many pushed back on the notion that healthcare could be a consumer-driven industry, arguing that it is fundamentally different from other markets. This chapter acknowledges and reviews these critiques, highlighting four areas that might present challenges to increasing consumer choice in healthcare: the special relationship between doctor and patient, ethics and morality, individual choice versus collective benefit, and the health consequences of consumer choice. In doing so, this chapter also presents a schematic for thinking about the different types of healthcare choices, arguing that not all choices are equal and consumers may be more prepared to make decisions in some areas as opposed to others. In presenting the counterargument to consumer choice, this chapter asks the reader to consider the drawbacks and potential limitations of consumer choice in healthcare.

Vietnamese Historical Writing

2018 ◽  
Author(s):  
Patricia Pelley
Keyword(s):  
Cold War ◽  
East Asian ◽  
History Writing ◽  
Southern State ◽  
The Past ◽  
South Vietnam ◽  
Political Function ◽  
Different Types ◽  
The Cold War ◽  
North Vietnam

This chapter demonstrates how the process of decolonization and the ensuing separation of Vietnam into a northern and southern state as part of the Cold War in Asia led to different types of history-writing. In both Vietnamese regimes, the writing of history had to serve the state, and in both countries historians emphasized its political function. Whereas North Vietnam located itself in an East Asian and Marxist context, historians of South Vietnam positioned it within a Southeast Asian setting and took a determinedly anti-communist position. After 1986—over a decade after reunification—with past tensions now relaxed, the past could be revaluated more openly under a reformist Vietnamese government that now also permitted much greater interaction with foreign historians.

scholarly journals Latest Developments in Insect Sex Pheromone Research and Its Application in Agricultural Pest Management

Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 484
Author(s):  
Syed Arif Hussain Rizvi ◽  
Justin George ◽  
Gadi V. P. Reddy ◽  
Xinnian Zeng ◽  
Angel Guerrero
Keyword(s):  
Sex Pheromone ◽  
Pest Management ◽  
Interdisciplinary Approach ◽  
Pheromone Biosynthesis ◽  
Insect Pheromones ◽  
Agricultural Pest ◽  
Practical Applications ◽  
The Past ◽  
Significant Research ◽  
Recent Developments

Since the first identification of the silkworm moth sex pheromone in 1959, significant research has been reported on identifying and unravelling the sex pheromone mechanisms of hundreds of insect species. In the past two decades, the number of research studies on new insect pheromones, pheromone biosynthesis, mode of action, peripheral olfactory and neural mechanisms, and their practical applications in Integrated Pest Management has increased dramatically. An interdisciplinary approach that uses the advances and new techniques in analytical chemistry, chemical ecology, neurophysiology, genetics, and evolutionary and molecular biology has helped us to better understand the pheromone perception mechanisms and its practical application in agricultural pest management. In this review, we present the most recent developments in pheromone research and its application in the past two decades.

Different Types of Auricular Keloids and Treatment by Intralesional Cryosurgery: Best Practice for Obtaining Long-Lasting Clinical Results

Dermatology ◽  
2021 ◽  
pp. 1-10
Author(s):  
Yaron Har-Shai ◽  
Lior Har-Shai ◽  
Viktor A. Zouboulis ◽  
Christos C. Zouboulis
Keyword(s):  
Quality Of Life ◽  
Body Image ◽  
Recurrence Rate ◽  
Best Practice ◽  
Clinical Results ◽  
Psychosocial Impact ◽  
Aesthetic Outcome ◽  
The Past ◽  
Different Types

<b><i>Background:</i></b> Auricular keloids belong to the most perplexing medical conditions, which have significant psychosocial impact on the patient’s body image and quality of life. <b><i>Summary:</i></b> The article is purposed to provide dermatologists and plastic surgeons with the best proven practice using intralesional cryosurgery for the treatment of the different auricular keloid types in order to obtain superior clinical results by minimizing the probability of recurrence. In the past 20 years, the authors have developed novel procedures in order to increase the effectiveness of intralesional cryosurgery on auricular keloids, including hydrodissection, warm gauze technique, and excision of dangling skin. Long-lasting clinical results with a low recurrence rate and a satisfactory aesthetic outcome are achieved with no deformation of the ear framework.

scholarly journals Flexibility of joint production in mixed fisheries and implications for management

2021 ◽  
Author(s):  
Florence Briton ◽  
Olivier Thébaud ◽  
Claire Macher ◽  
Caleb Gardner ◽  
Lorne Richard Little
Keyword(s):  
Economic Performance ◽  
Economic Incentives ◽  
Joint Production ◽  
Total Allowable Catch ◽  
Individual Transferable Quotas ◽  
The Past ◽  
Different Types ◽  
Commercial Species ◽  
Management Recommendations ◽  
Production Problems

Abstract Over the past decade, efforts have been made to factor technical interactions into management recommendations for mixed fisheries. Yet, the dynamics underlying joint production in mixed fisheries are generally poorly captured in operational mixed fisheries models supporting total allowable catch advice. Using an integrated ecological–economic simulation model, we explore the extent to which fishers are likely to alter the species composition of their landings in a mixed fishery managed with individual transferable quotas, the Australian Southern and Eastern Scalefish and Shark Fishery. Our simulations capture three different types of joint production problems, highlighting the flexibility that exists in terms of achievable catch compositions when quota markets provide the economic incentives to adapt fishing practices to quota availability. These results highlight the importance of capturing the drivers of fishing choices when advising TAC decisions in mixed fisheries. We also identify a hierarchy of species in this fishery, with harvest targets set for primary commercial species determining most of its socio-economic performance.

scholarly journals A Technical Study on UAV Characteristics for Precision Agriculture Applications and Associated Practical Challenges

2021 ◽  
Vol 13 (6) ◽  
pp. 1204
Author(s):  
Nadia Delavarpour ◽  
Cengiz Koparan ◽  
John Nowatzki ◽  
Sreekala Bajwa ◽  
Xin Sun
Keyword(s):  
Precision Agriculture ◽  
Weather Conditions ◽  
Future Directions ◽  
Radiometric Correction ◽  
Practical Applications ◽  
The Past ◽  
Field Crops ◽  
Advanced Technologies ◽  
Technical Study ◽  
Agricultural Operations

The incorporation of advanced technologies into Unmanned Aerial Vehicles (UAVs) platforms have enabled many practical applications in Precision Agriculture (PA) over the past decade. These PA tools offer capabilities that increase agricultural productivity and inputs’ efficiency and minimize operational costs simultaneously. However, these platforms also have some constraints that limit the application of UAVs in agricultural operations. The constraints include limitations in providing imagery of adequate spatial and temporal resolutions, dependency on weather conditions, and geometric and radiometric correction requirements. In this paper, a practical guide on technical characterizations of common types of UAVs used in PA is presented. This paper helps select the most suitable UAVs and on-board sensors for different agricultural operations by considering all the possible constraints. Over a hundred research studies were reviewed on UAVs applications in PA and practical challenges in monitoring and mapping field crops. We concluded by providing suggestions and future directions to overcome challenges in optimizing operational proficiency.

scholarly journals O21 The incidence of COVID-19 among children with rheumatic diseases receiving biological agents

Rheumatology ◽  
2021 ◽  
Vol 60 (Supplement_1) ◽  
Author(s):  
Nadezhda Tsurikova ◽  
Elena Ligostaeva ◽  
Vadim Avdeenko ◽  
Nataliya Kobzeva ◽  
Irina Tsiganok ◽  
...  
Keyword(s):  
Rheumatic Diseases ◽  
Lupus Erythematosus ◽  
Biological Agents ◽  
Tnf Receptor ◽  
The Past ◽  
Different Types ◽  
Mediterranean Fever ◽  
Positive Results ◽  
Single Center Observational Study

Abstract Background/Aims  During the COVID-19 pandemic, analysis of the incidence of COVID-19 among patients suffering from rheumatic diseases and receiving therapy with biological agents remains relevant. Methods  This single-center observational study included 118 children suffering from various rheumatic diseases and receiving therapy with anti-rheumatic drugs and biological agents. In this research, we analyzed the incidence of CIVID-19 and the frequency of documented contact with SARS-CoV-2 in the period from 01.03.2020 to 11.10.2020 (32 weeks). The results were analyzed using descriptive statistics. Results  Among 118 children, there were 28 (24%) boys and 90 (76%) girls, average age 10.3±4.2. 104 (88.2%) patients had different types of juvenile idiopathic arthritis (JIA), 2 (1.6%) children had systemic lupus erythematosus (SLE), 2 (1.6%) patients had juvenile dermatomyositis (JDM), 1 (1%) child had ANCA-associated vasculitis, 6 (5%) patients had familial Mediterranean fever (FMF), 2 (1.6%) children had deficiency of adenosine deaminase 2 (DADA2), 1 (1%) child had TNF receptor-associated periodic syndrome (TRAPS). In this group of patients 94 (79%) patients were treated with methotrexate, 1 (1%) - azathioprine, 3 (2%) patients received hydroxychloroquine, 6(5%) - mycophenolate mofetil, 4 (3%) - sulfasalazine, 14(11%) children received prednisone, 6(5%) - cyclosporine A. All children included in this study received biological agents for more than 1 year, the distribution of biological agents among patients was as follows: 41(34%) - etanercept, 33(28%) - adalimumab, 24 (20%) - tocilizumab, 7 (6%) - canakinumab, 3 (2%) - abatacept, 4 (3%) - golimumab, 6 (5%) - rituximab. Out of 118 children, 4 (3%) patients had flu-like symptoms and positive results of PCR tests for COVID-19 (1 patient was treated with etanercept, 1 - adalimumab, 1 - tocilizumab, 1 - rituximab), none of the patients had signs of SARS-CoV-2 pneumonia. 10 (8%) patients had documented contact with COVID-19: among this patients 2 children had flu-like symptoms, positive results of PCR tests and absence of COVID-19 pneumonia (one of this patient was treated with adalimumab, another one - with rituximab), one more patient was treated with tocilizumab and had positive PCR test without any symptoms of COVID-19; other 7 children had negative PCR tests and didn’t have any signs of COVID-19. Conclusion  Among our patients with various rheumatic diseases treated with biological agents there were no registered severe cases of COVID-19. Over the past period (32 weeks of follow-up) 3% of children with COVID-19 were identified and 8% patients had documented contact with COVID-19, but we suppose it is too early to make conclusions about the degree and severity of COVID-19 among children suffering from rheumatic diseases and receiving various biological agents. Further follow-up is needed to better understand the risk and impact of COVID-19 among children with rheumatic diseases and receiving therapy with biological agents. Disclosure  N. Tsurikova: None. E. Ligostaeva: None. V. Avdeenko: None. N. Kobzeva: None. I. Tsiganok: None. K. Skorobogatova: None. A. Motkina: None.

2D Self-assembly and Electronic Characterization of Oxygen-Boron-Oxygen-Doped Chiral Graphene Nanoribbons

2021 ◽  
Author(s):  
Lei Jin ◽  
Nerea Bilbao ◽  
Yang Lv ◽  
Xiao-Ye Wang ◽  
Soltani Paniz ◽  
...  
Keyword(s):  
Edge Effects ◽  
Self Assembly ◽  
Quantum Confinement ◽  
Graphene Nanoribbons ◽  
One Dimensional ◽  
The Past ◽  
Different Types

Graphene nanoribbons (GNRs), quasi-one-dimensional strips of graphene, exhibit a nonzero bandgap due to quantum confinement and edge effects. In the past decade, different types of GNRs with atomically precise structures...

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