Contralateral Boundary Conditions Affect the Biomechanical Response of the Pubic Symphysis During Pelvic Side Impacts

Clearer understanding of the biomechanics of the pubic symphysis in lateral pelvic impact tests may serve to elucidate the mechanisms of injury in automotive side impacts. While numerous experimental and computational studies have been conducted on the human pelvis, stresses and deformations of the symphysis were never measured, and the role of the boundary conditions supporting the pelvis was not emphasized. The objective of the present study was to develop a biofidelic FE model to investigate the deformations and stresses experienced by the pubic ligaments and interpubic disc under side impact conditions simulating both drop tower experiments and automotive side impacts.

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Significant Severity Reduction of Side-Impact Injuries by Using ITS Airbags: FE Simulation and Severity Analysis

Transportation: Making Tracks for Tomorrow’s Transportation ◽

10.1115/imece2002-39083 ◽

2002 ◽

Author(s):

Tarek A. Omar ◽

Nabih E. Bedewi ◽

Azim Eskandarian

Keyword(s):

Model Performance ◽

Side Impact ◽

Fe Model ◽

Severe Injuries ◽

Side Impacts ◽

Head Protection ◽

Life Saving ◽

Head Injury Criteria ◽

Moving Deformable Barrier ◽

The Impact

The Inflatable Tubular Structure (ITS) airbag is a potentially life-saving device that has been implemented recently in some luxury vehicles. Its main objective is to provide head protection for the front seat occupants against upper side-interior car components. In a previous research conducted by the authors, a nonlinear Finite Element (FE) model for the ITS-airbag system was successfully developed and tested. In the current research, the developed ITS model is combined with a full-scale FE vehicle model and 50th percentile side-impact dummy (SID) model. The combined model is then used to conduct two series of side-impact simulations. The first series included side impacts with narrow objects, i.e. rigid poles, while the second series included side impacts with a Moving Deformable Barrier (MDB) as a wide and deformable object. The effect of the relative position between the dummy and the rigid pole was considered by conducting variety of simulations for two different rigid pole positions and three different dummy positions. The three dummy positions were considered in the side impacts with the MDB. For both impact series, the effect of the impact velocity was considered by conducting each impact scenario at three different velocities. The ITS model performance, in all FE simulations, was fairly similar to the actual ITS performance. The simulation results indicated a significant reduction in the Head Injury Criteria (HIC) of the dummy head due to the ITS-airbag deployment. The life-threatening severity for occupants is usually measured by the Abbreviated Injury Scale (AIS) that ranges from 1 (minor) to 6 (fatal). The AIS indices are calculated in all side impacts. The results demonstrated a significant reduction/elimination in fatalities and severe injuries due to the ITS-airbag performance. The results clearly indicated the great benefits expected from this promising safety device.

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Road vehicles. Injury risk curves for the evaluation of occupant protection in side impact tests

10.3403/30216117 ◽

2013 ◽

Keyword(s):

Injury Risk ◽

Side Impact ◽

Road Vehicles ◽

Occupant Protection ◽

Impact Tests ◽

Risk Curves

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Isolation of Natural Compounds from Syzygium densiflorum Fruits and Exploring its Chemical Property, Therapeutic Role in Diabetic Management

The Natural Products Journal ◽

10.2174/2210315508666180622113414 ◽

2020 ◽

Vol 10 (2) ◽

pp. 168-176

Author(s):

Krishnasamy Gopinath ◽

Nagarajan Subbiah ◽

Muthusamy Karthikeyan

Keyword(s):

Density Functional ◽

Chemical Reactivity ◽

Natural Compounds ◽

Structure Activity Relationship ◽

Activity Relationship ◽

Computational Studies ◽

Therapeutic Role ◽

Relationship Analysis ◽

Structure Activity

Background: Syzygium densiflorum Wall. ex Wight & Arn (Myrtaceae) has been traditionally used by the local tribes of the Nilgiris, Tamil Nadu, India, for the treatment of diabetes. Objective: This study aimed to isolate the major phytoconstituents from the S. densiflorum fruits and to perform computational studies for chemical reactivity and biological activity of the isolated compound. Materials and Methods: Two different compounds were isolated from ethanolic extract of S. densiflorum fruits and purified using HPLC. The structures of the compounds were elucidated on the basis of their 1H NMR, 13C NMR, 1H-1H COSY, HMBC, HRESIMS, and FT-IR data. Further, the chemical reactivity of the compounds was analyzed by density functional theory calculations and its therapeutic role in diabetic management was examined by comparing the structure of isolated compounds with previously reported bioactive compounds. Results: Of the two compounds ((6,6 & 1-kestopentaose (1) and 6-(hydroxymethyl)-3-[3,4,5- trihydroxy- 6-[(3,4,5-trihydroxyoxan-2-yl)oxymethyl]oxan-2-yl]oxyoxane-2,4,5-triol)(2)). β-glucosidase, β-galactosidase, α-glucosidase and β-amylase inhibition activity of the compounds were predicted by structure activity relationship. Conclusion: Structure-activity relationship analysis was performed to predict the therapeutic role of isolated compounds. These computational studies may be performed to minimize the efforts to determine the therapeutic role of natural compounds.

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Determining preference for potential: The role of perceived economic mobility

Social Behavior and Personality An International Journal ◽

10.2224/sbp.8019 ◽

2019 ◽

Vol 47 (6) ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Chen Yang ◽

Shaochen Zhao

Keyword(s):

Boundary Conditions ◽

Economic Mobility ◽

Individual Perceptions ◽

Future Success ◽

The Future

Although previous researchers have demonstrated that people often prefer potential rather than achievement when evaluating other people or products, few have focused on the boundary conditions on this effect. We proposed that the preference for potential would emerge when individuals’ perception of economic mobility was high, but the preference for achievement would emerge among individuals with low perceptions of economic mobility. Our results showed that people paid more attention to the future (vs. the present) when their perception of economic mobility was high; this, in turn, promoted more favorable reactions toward potential (vs. achievement). Thus, we suggested circumstances under which highlighting a person’s potential for future success is effective and those when it is not effective. Moreover, we revealed the important role of individual perceptions regarding economic mobility in driving this effect.

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Charge algebra in Al(A)dSn spacetimes

Journal of High Energy Physics ◽

10.1007/jhep05(2021)210 ◽

2021 ◽

Vol 2021 (5) ◽

Author(s):

Adrien Fiorucci ◽

Romain Ruzziconi

Keyword(s):

Boundary Conditions ◽

Dirichlet Boundary ◽

Three Dimensional ◽

Dirichlet Boundary Conditions ◽

Boundary Structure ◽

Asymptotic Symmetry ◽

Renormalization Procedure ◽

Field Dependent ◽

Odd Dimensions

Abstract The gravitational charge algebra of generic asymptotically locally (A)dS spacetimes is derived in n dimensions. The analysis is performed in the Starobinsky/Fefferman-Graham gauge, without assuming any further boundary condition than the minimal falloffs for conformal compactification. In particular, the boundary structure is allowed to fluctuate and plays the role of source yielding some symplectic flux at the boundary. Using the holographic renormalization procedure, the divergences are removed from the symplectic structure, which leads to finite expressions. The charges associated with boundary diffeomorphisms are generically non-vanishing, non-integrable and not conserved, while those associated with boundary Weyl rescalings are non-vanishing only in odd dimensions due to the presence of Weyl anomalies in the dual theory. The charge algebra exhibits a field-dependent 2-cocycle in odd dimensions. When the general framework is restricted to three-dimensional asymptotically AdS spacetimes with Dirichlet boundary conditions, the 2-cocycle reduces to the Brown-Henneaux central extension. The analysis is also specified to leaky boundary conditions in asymptotically locally (A)dS spacetimes that lead to the Λ-BMS asymptotic symmetry group. In the flat limit, the latter contracts into the BMS group in n dimensions.

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Natural Disasters and Economic Growth: The Mitigating Role of Microfinance Institutions

Sustainability ◽

10.3390/su13095055 ◽

2021 ◽

Vol 13 (9) ◽

pp. 5055

Author(s):

John Sseruyange ◽

Jeroen Klomp

Keyword(s):

Developing Countries ◽

Natural Disasters ◽

Legal Status ◽

Agricultural Sector ◽

Banking System ◽

Fe Model ◽

Microfinance Institutions ◽

Natural Event ◽

Negative Effect

In this study, we explore whether microfinance institutions (MFIs) can mitigate the adverse macroeconomic consequences of natural disasters. The provision of capital immediately following a natural event is recognized as one of the necessary conditions for a fast economic recovery. However, one concern is that a large majority of natural disasters occur in developing countries where households and the private sector have only limited access to the formal banking system. As an alternative, MFIs may fill up this gap in providing liquidity in the form of microcredit. The existing evidence on how MFIs respond to disaster effects is foremost based on case and micro-level evidence. In turn, the focus of this study is more on the macro impact of MFI activities after a natural disaster. Based on the finding obtained from an OLS-FE model using an unbalanced panel considering more than 80 developing countries and emerging economies, we can conclude that natural disasters harm macroeconomic performance primarily through their effect on the agricultural sector. However, access to lending facilities from MFIs mitigates a large part of this negative effect. Moreover, the extent to which MFIs are able to mitigate these effects depends to a great extent on their nature, i.e., their organizational structure, profitability, legal status, age, and the number of clients they serve.

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Understanding the critical role of boundary conditions in meso-scale finite element simulation of braided composites

Advanced Composites and Hybrid Materials ◽

10.1007/s42114-021-00284-3 ◽

2021 ◽

Author(s):

Zhenqiang Zhao ◽

Peng Liu ◽

Haoyuan Dang ◽

Yang Chen ◽

Chao Zhang ◽

...

Keyword(s):

Finite Element ◽

Boundary Conditions ◽

Finite Element Simulation ◽

Critical Role ◽

Braided Composites ◽

Element Simulation ◽

Meso Scale

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Mechanics of tubular helical assemblies: ensemble response to axial compression and extension

Acta Mechanica Sinica ◽

10.1007/s10409-021-01068-0 ◽

2021 ◽

Author(s):

Jacopo Quaglierini ◽

Alessandro Lucantonio ◽

Antonio DeSimone

Keyword(s):

Boundary Conditions ◽

Elastic Properties ◽

Central Region ◽

Mechanical Response ◽

Different Boundary Conditions ◽

Kirchhoff Rods ◽

Model Versus ◽

The Individual ◽

Opposite Chirality

Abstract Nature and technology often adopt structures that can be described as tubular helical assemblies. However, the role and mechanisms of these structures remain elusive. In this paper, we study the mechanical response under compression and extension of a tubular assembly composed of 8 helical Kirchhoff rods, arranged in pairs with opposite chirality and connected by pin joints, both analytically and numerically. We first focus on compression and find that, whereas a single helical rod would buckle, the rods of the assembly deform coherently as stable helical shapes wound around a common axis. Moreover, we investigate the response of the assembly under different boundary conditions, highlighting the emergence of a central region where rods remain circular helices. Secondly, we study the effects of different hypotheses on the elastic properties of rods, i.e., stress-free rods when straight versus when circular helices, Kirchhoff’s rod model versus Sadowsky’s ribbon model. Summing up, our findings highlight the key role of mutual interactions in generating a stable ensemble response that preserves the helical shape of the individual rods, as well as some interesting features, and they shed some light on the reasons why helical shapes in tubular assemblies are so common and persistent in nature and technology. Graphic Abstract We study the mechanical response under compression/extension of an assembly composed of 8 helical rods, pin-jointed and arranged in pairs with opposite chirality. In compression we find that, whereas a single rod buckles (a), the rods of the assembly deform as stable helical shapes (b). We investigate the effect of different boundary conditions and elastic properties on the mechanical response, and find that the deformed geometries exhibit a common central region where rods remain circular helices. Our findings highlight the key role of mutual interactions in the ensemble response and shed some light on the reasons why tubular helical assemblies are so common and persistent.

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