Calculation of Residual Deformations of Granulated Materials from Exposure to Repeated Loads

2020 ◽  
Vol 992 ◽  
pp. 828-835
Author(s):  
A.S. Aleksandrov ◽  
T.V. Semenova ◽  
N.P. Aleksandrova
Keyword(s):  
Granular Materials ◽  
Triaxial Compression ◽  
Residual Deformation ◽  
Load Application ◽  
Crushed Stone ◽  
Integral Calculus ◽  
Short Period ◽  
Residual Deformations ◽  
The Impact ◽  
Repeated Loads

The analysis of the models for calculating residual deformations accumulated by granular materials under the influence of repeated loads is performed. Determined the hereditary nature of the accumulation of deformation of granular materials. This allowed the use of integral calculus for the analytical solution of the problem of the dependence of residual deformation on the number of repeated loads, the value of the main stresses. The solution is obtained in the form of logarithmic and power-law functions that associate the accumulated deformation with the deformation arising from the first load application with the number of applied loads. The deformation from the first load application is represented by the sum of the two components, instantaneous irreversible and viscoplastic. The viscoplastic component of the deformation is a consequence of stress relaxation in a relatively short period of time equal to the duration of the impact of the load. The analysis of experimental data on the triaxial compression of various granular materials is carried out and the parameters obtained for the power and logarithmic functions are determined. The materials studied include: granite, gneissic, granodiorite and diorite crushed stone, sand and gravel and crushed stone and gravel mixtures with a mineral part from various rocks, fortified sands. The possibility of application of the obtained solutions for the calculation displacement of the surface of the pavement layers of granular materials is shown. The tasks of further research are formulated.

scholarly journals MATERIALS USED IN THE ROAD BASES: METHOD OF THE RESIDUAL DEFORMATIONS’ CALCULATION

2019 ◽  
Vol 16 (4) ◽  
pp. 456-471
Author(s):  
A. S. Aleksandrov ◽  
T. V. Semenova ◽  
N. P. Aleksandrova
Keyword(s):  
Granular Materials ◽  
Elastoplastic Deformation ◽  
Residual Deformation ◽  
Load Application ◽  
Crushed Stone ◽  
Viscoplastic Deformation ◽  
Power Functions ◽  
Short Period ◽  
Residual Deformations ◽  
Repeated Loads

Materials and methods. The authors performed the analysis of the models for calculating residual deformations accumulated by granular materials and under the influence of repeated loads. The research showed the hereditary nature of the strain granular materials’ accumulation. Therefore, the authors used integral calculus for analytical solution of the residual deformation’s dependence on the number of repeated loads and on the magnitude of the main stresses. Moreover, the authors obtained the solution in the form of logarithmic and power functions, which associated the accumulated deformation with the deformation arising from the first load application. In determining the deformation from the first load application, the authors took into account the model of the theory of plasticity, in which the elastoplastic deformation was determined by the sum of two components elastic and plastic, as well as rheological models considering the deformation as the sum of three or four components. Generalizing the model for various materials, the authors gave the preference to the model, in which the elastoplastic deformation was determined by four components: instantaneous elastic and residual deformations, elastic (elastic-viscous) deformation and a viscoplastic component. Therefore, the residual strain from the first load application was represented by the sum of the two components, instantaneous irreversible and viscoplastic. The viscoplastic component of the deformation was a result of stress relaxation in a relatively short period of time equal to the duration of the load impact. Such research allowed taking into account the effect of speed on the duration of the load and the magnitude of the viscoplastic component of the residual deformation. The authors emphasized that taking into account the viscous-plastic component of residual deformation was most appropriate when calculating residual deformations of soils and materials treated with an organic binder. Granular materials were less sensitive to viscoplastic deformation under a single load application, but, when the voltage exceeded the elastic limit, and the more plastic adaptability of crushed stone, gravel, etc. viscoplastic deformation made a significant contribution to the accumulated residual deformation.Results. As a result, the authors carried out the analysis of experimental data on the triaxial compression of various granular materials and determined the parameters obtained for the power and logarithmic functions. The authors studied such materials as granite, gneissic, granodiorite and diorite crushed stone, sand, gravel and crushed stone, gravel mixtures with a mineral part from various rocks and fortified sands.Discussion and conclusions. The paper demonstrates the possibility of using the solutions for calculation of the surface displacement of the pavement layers of granular materials. The authors formulate the tasks for further research.

HBOT Application at Cases of Gingival Inflammation

2019 ◽  
Author(s):  
Ilma Robo
Keyword(s):  
Root Resorption ◽  
Periodontal Diseases ◽  
Therapeutic Effects ◽  
Clinical Effects ◽  
Gingival Inflammation ◽  
Beneficial Effects ◽  
New Therapeutic Approaches ◽  
Short Period ◽  
Mechanical Therapy ◽  
The Impact

The treatment of periodontal diseases, mainly of their origin, with the most common clinical manifestation in form of gingival inflammation, is manifold and powerful, including: mechanical therapy, antibiotic, antiseptic and various approaches to treatment, which are recommended to be used within a short period of time. New therapeutic approaches have been proven as alternative treatment to conventional therapy, or in combination with conventional therapies, to reduce the number of periodontopathic pathogens in gingival sulcus. HBOT has a detrimental effect on periodontal microorganisms, as well as beneficial effects on the healing of periodontal tissue, increasing oxygen pressure in gingival pockets. Our study is aimed at reviewing the current published literature on hyperbaric oxygen therapy and focuses on role of HBOT as a therapeutic measure for the individual with periodontal disease in general and for the impact on the recovery of gingival inflammation. HBOT and periodontal treatment together, reduce up to 99% of the gram-negative anaerobic load of subgingival flora. HBOT, significantly reduces subgingival anaerobic flora. Clinical effects in 2-year follow-up of treated patients are sensitive. Reduction of gingival hemorrhage indexes, depth of peritoneum, plaque index, occurs in cases of combination of HBOT and detraction. Reduced load persists up to 2 months after therapy. The significant increase in connective tissue removal starts at the end of 2nd week, to achieve the maximum in week 3-6 of application. HBOT used for re-implantation, stimulates the healing of periodontal membrane, pulp, prevents root resorption, healing of periodontal lining tissues. HBOT, significantly reduces the hemorrhage index with 1.2 value difference, 0.7mm probe depth, reduces gingival fluid by 2. HGH exposure is increased by gingival blood flow, with a difference of 2 in measured value. The therapeutic effects of HBOT in the value of the evaluation index can be saved up to 1-year post treatment.

scholarly journals Ovarian Dysgerminoma in Pregnant Women with Viable Fetus: A Rare Case Report

2021 ◽  
pp. 141-146
Author(s):  
Reda Youssef ◽  
Gamal Sayed Ahmed ◽  
Samir Alhyassat ◽  
Sanaa Badr ◽  
Ahmed Sabry ◽  
...  
Keyword(s):  
Gestational Age ◽  
Ovarian Neoplasms ◽  
Imaging Modality ◽  
Reproductive Age ◽  
Diagnostic Challenge ◽  
Short Period ◽  
Ovarian Dysgerminoma ◽  
The Impact ◽  
In Pregnancy

Dysgerminoma is an uncommon malignant tumor arising from the germ cells of the ovary. Its association with pregnancy is extremely rare, with a reported incidence of about 0.2–1 per 100,000 pregnancies. Women in the reproductive age group are more commonly affected. It can be extremely rare to conceive naturally, without assisted reproductive interventions, in cases with ovarian dysgerminoma. If a pregnancy does occur with a concurrent dysgerminoma, it is even more unusual to carry the pregnancy to viability or childbirth without fetal or maternal compromise. We report a case of right ovarian dysgerminoma in a young female with a viable intrauterine pregnancy at 10 weeks, which is rarely diagnosed and managed at this gestational age. Numerous factors played a role in her favorable outcome, including early suspicion by ultrasound and presenting history, surgery, histopathological assessment, imaging, and involvement of the multidisciplinary oncology team. Ovarian neoplasms may rapidly increase in size within a short period with little or no symptoms. This poses a diagnostic challenge for obstetricians and oncologists. Hence, we aimed to evaluate the role of imaging in pregnancy using ultrasound as an imaging modality for both early detection of ovarian neoplasms and for follow-up. In conclusion, patients with ovarian dysgerminoma in pregnancy can have favorable outcomes. Treatment should be individualized on a case-to-case basis, depending on many factors; cancer stage, previous reproductive history, the impact of imaging in staging or follow-up of tumor on the fetus, fetal gestational age, and whether termination of the pregnancy can improve survival or morbidity for the mother.

scholarly journals MitoQ Is Able to Modulate Apoptosis and Inflammation

2021 ◽  
Vol 22 (9) ◽  
pp. 4753
Author(s):  
Elisa Piscianz ◽  
Alessandra Tesser ◽  
Erika Rimondi ◽  
Elisabetta Melloni ◽  
Claudio Celeghini ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Mevalonate Pathway ◽  
Neuronal Cell ◽  
Reactive Oxygen ◽  
Mitochondrial Activity ◽  
Oxygen Species ◽  
Short Period ◽  
Inflammatory Stimuli ◽  
Apoptosis And Inflammation ◽  
The Impact

Mitoquinone (MitoQ) is a mitochondrial reactive oxygen species scavenger that is characterized by high bioavailability. Prior studies have demonstrated its neuroprotective potential. Indeed, the release of reactive oxygen species due to damage to mitochondrial components plays a pivotal role in the pathogenesis of several neurodegenerative diseases. The present study aimed to examine the impact of the inflammation platform activation on the neuronal cell line (DAOY) treated with specific inflammatory stimuli and whether MitoQ addition can modulate these deregulations. DAOY cells were pre-treated with MitoQ and then stimulated by a blockade of the cholesterol pathway, also called mevalonate pathway, using a statin, mimicking cholesterol deregulation, a common parameter present in some neurodegenerative and autoinflammatory diseases. To verify the role played by MitoQ, we examined the expression of genes involved in the inflammation mechanism and the mitochondrial activity at different time points. In this experimental design, MitoQ showed a protective effect against the blockade of the mevalonate pathway in a short period (12 h) but did not persist for a long time (24 and 48 h). The results obtained highlight the anti-inflammatory properties of MitoQ and open the question about its application as an effective adjuvant for the treatment of the autoinflammatory disease characterized by a cholesterol deregulation pathway that involves mitochondrial homeostasis.

When I am old I shall wear purple: a qualitative study of the effect of group poetry sessions on the well-being of older adults

2016 ◽  
Vol 20 (4) ◽  
pp. 195-198 ◽  
Author(s):  
Richard Seymour ◽  
Michael Murray
Keyword(s):  
Older People ◽  
Assisted Living ◽  
Well Being ◽  
Content Type ◽  
Short Period ◽  
Different Types ◽  
Poetry Reading ◽  
The Impact ◽  
Health And Well Being ◽  
Practical Implications

Purpose There is increasing evidence that participation in various art forms can be beneficial for health and well-being. The purpose of this paper is to examine the impact of participating in a poetry reading group on a group of older residents of an assisted living facility. Design/methodology/approach Six poetry sessions, each on a different theme, were conducted with a group of volunteer participants. These sessions, those of pre- and post-study focus groups and interviews with the group facilitator and staff contact were audio-recorded. The transcripts of the recordings were then subjected to a thematic analysis. Findings Overall the participants were enthused by the opportunity to participate in the project and the benefits were confirmed by the support staff. In addition, reading poetry on particular themes promoted different types of discussion. Research limitations/implications The number of participants in this study was small and the study was conducted over a short period of time. Practical implications This paper confirms the impact of poetry reading for older people. The challenge is to explore this impact in more detail and over community as well as residential settings. Originality/value This paper is the first empirical report on the value of poetry reading for older people.

Risks of the Digitalization of Life of the Population and Ways of Decreasing Them

2021 ◽  
Vol 13 (4-1) ◽  
pp. 180-203
Author(s):  
Elena Stukalenko ◽  
Keyword(s):  
Quality Of Life ◽  
Digital Technologies ◽  
Well Being ◽  
Digital Economy ◽  
Digital Transformation ◽  
Negative Consequences ◽  
Short Period ◽  
The World ◽  
The Impact

Digital technologies, ubiquitous in our daily life, have radically changed the way we work, communicate, and consume in a short period of time. They affect all components of quality of life: well-being, work, health, education, social connections, environmental quality, the ability to participate and govern civil society, and so on. Digital transformation creates both opportunities and serious risks to the well-being of people. Researchers and statistical agencies around the world are facing a major challenge to develop new tools to analyze the impact of digital transformation on the well-being of the population. The risks are very diverse in nature and it is very difficult to identify the key factor. All researchers conclude that secure digital technologies significantly improve the lives of those who have the skills to use them and pose a serious risk of inequality for society, as they introduce a digital divide between those who have the skills to use them and those who do not. In the article, the author examines the risks created by digital technologies for some components of the quality of life (digital component of the quality of life), which are six main components: the digital quality of the population, providing the population with digital benefits, the labor market in the digital economy, the impact of digitalization on the social sphere, state electronic services for the population and the security of information activities. The study was carried out on the basis of the available statistical base and the results of research by scientists from different countries of the world. The risks of the digital economy cannot be ignored when pursuing state social policy. Attention is paid to government regulation aimed at reducing the negative consequences of digitalization through the prism of national, federal projects and other events.

CASE STUDY ON CIRCUMSCRIBED GLIOMAS, THEIR CLINICOPATHOLOGICAL CORRELATION IN A TERTIARY CARE CENTER

2021 ◽  
pp. 42-45
Author(s):  
Esther Alffi Papang ◽  
K. Rama
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Tertiary Care ◽  
Biological Behavior ◽  
Low Grade ◽  
Lower Grade ◽  
Who Grade ◽  
Primary Tumors ◽  
Short Period ◽  
The Impact

The histogenesis and biological behavior of primary tumors of the central nervous system(CNS) are very diverse. The majority of present gliomas as benign, slow growing lesions classied as by the WHO classicati grade I or II (Low grade gliomas) on of CNS tumors. However, a signicant fraction of gliomas develop over a short period of time and progress rapidly and are therefore classied as WHO grade III or IV(High grade gliomas). Astrocytomas are primary central nervous system tumours that can develop in adults or in children. They arise from the Astrocytes. They can be divided into diffuse that generally have a higher grade and poorer prognosis and those that are localised that tend to be of a lower grade and have a better prognosis. In this study, we outline the basic histological spectrum and features, epidemiological aspects and grade of circumscribed gliomas (localised) or other Astrocytic tumours according to WHO classication . These are the Pilocytic Astrocytoma, Pilomyxoid Astrocytoma, Subependymal giant cell Astrocytoma, Pleomorphic xanthoastrocytoma and Anaplastic astrocytoma . The knowledge of these tumours are important as they are one of the commonest cause of mortality and morbidity in both the young and old, accounting for about 60% of the glial tumours. Therefore neuropathological diagnosis and tumour characteristics will therefore profoundly inuence the impact of treatment strategies.

scholarly journals Alcohol Pattern Consumption Differently Affects the Efficiency of Macrophage Reverse Cholesterol Transport in Vivo

Nutrients ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1885
Author(s):  
Daniela Greco ◽  
Simone Battista ◽  
Laura Mele ◽  
Antonio Piemontese ◽  
Bianca Papotti ◽  
...  
Keyword(s):  
Reverse Cholesterol Transport ◽  
Disease Risk ◽  
Cardiovascular Disease Risk ◽  
The Body ◽  
Cholesterol Transport ◽  
Drinking Patterns ◽  
Cardiovascular Morbidity And Mortality ◽  
Short Period ◽  
The Impact

It has been well established that moderate alcohol consumption inversely correlates with cardiovascular morbidity and mortality, whereas binge alcohol drinking increases cardiovascular disease risk. The aim of this study was to assess in vivo the impact of different drinking patterns on reverse cholesterol transport (RCT); the atheroprotective process leading to the removal of excess cholesterol from the body. RCT was measured with a standardized, radioisotope-based technique in three groups of atherosclerosis-prone apolipoprotein E knock out mice: Placebo group, receiving water, which would mimic the abstainers; moderate group, receiving 0.8 g/kg alcohol/day for 28 days, which would mimic a moderate intake; binge group, receiving 0.8 g/kg alcohol/day for 5 days/week, followed by the administration of 2.8 g/kg alcohol/day for 2 days/week, which would mimic a heavy intake in a short period. Mice in the binge drinking group displayed an increase in total cholesterol, high density lipoprotein cholesterol (HDL-c) and non-HDL-c (all p < 0.0001 vs. placebo), and a significantly reduced elimination of fecal cholesterol. The moderate consumption did not lead to any changes in circulating lipids, but slightly improved cholesterol mobilization along the RCT pathway. Overall, our data confirm the importance of considering not only the total amount, but also the different consumption patterns to define the impact of alcohol on cardiovascular risk.

scholarly journals Impact of Slab Thickness on Reinforced Concrete Buildings using Fragility Curves

2020 ◽  
Vol 8 (5) ◽  
pp. 4533-4538
Keyword(s):  
Reinforced Concrete ◽  
Fragility Curves ◽  
Structural Response ◽  
Software Tool ◽  
Slab Thickness ◽  
Ground Shaking ◽  
Code Of Practice ◽  
Short Period ◽  
Rc Frame Structures ◽  
The Impact

Earthquakes are the natural disaster occurring since years but during the last two decades they are causing huge looses whether it may economic or to life. This paper focuses to evaluate the seismic performance of various building confirming to Indian standard criteria for earthquake resistant design of structures and ductile detailing of reinforced concrete structures subjected to seismic Forces-code of practice, Bureau of Indian Standards, both as per the revised codes in the year 2016. Due to ground shaking, seismic loads are the governing load and thus it becomes necessary to assess the conditional probability of structural response. Use of HAZUS methodology is followed to construct seismic fragility curves as it is well-organized and defined approach. Spectral displacement plays the functional parameter to derive the expected damage for fragility. This work represented here is compiled by means of procedure for establishing the fragility curves for three typical Reinforced Concrete (RC) frame structures having variations resembling 3 storey intended for short-period structures, 6 storey used for medium-period structures and 12 storey representing long-period structures using SAP2000 as a software tool for analyzing the structure. Furthermore an attempt is made for focus on the variation of one of the major structural configuration i.e. slab thickness which is not certainly paid attention as compared to columns and beams. Slabs adds additional stiffness to the structure which can enlighten how it behaviour would be when subjected to ground excitation. As a result, the fragility curves are plotted to study the impact due to slab thickness in order they are carefully selected while design.

scholarly journals THE IMPACT OF EU STRUCTURAL FUND SUPPORT AND PROBLEMS OF ITS ABSORPTION

2013 ◽  
Vol 11 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Daiva Jurevičienė ◽  
Jūratė Pileckaitė
Keyword(s):  
National Economy ◽  
Direct Investment ◽  
Statistical Data ◽  
Negative Impact ◽  
Structural Fund ◽  
Economic Activities ◽  
Structural Support ◽  
Short Period ◽  
The Impact ◽  
Eu Support

Targeted allocation of EU support in Lithuania can help resolving a number of problems and achieving significant results in a variety of areas. However, rush to absorb support may lead to a little, zero or even negative impact on national economy. In addition, EU support opportunities may distort investment motivation. This paper deals with issues related to the impact of EU support and problems of its absorption. The impact of EU support on the national economy has been established in three areas: attraction of foreign direct investment state investments into capital formation, and experience of companies, which are EU support beneficiaries. The paper proposes using regression analysis in search and evaluation of relations while obtaining more information about programmes, priorities and the impact of structural support on different indicators. In addition, it focuses on ascertaining the effectiveness of governmental and company spending. Furthermore, as companies – EU support beneficiaries – are engaged in different economic activities, their experience cannot be ascertained from statistical data; consequently, findings of an expert survey are presented to demonstrate the experience acquired by business companies as well as problems they face. Limitation of research was a short period of time to evaluate (only four years of the current funding period)

Sign in / Sign up

Export Citation Format

Share Document