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Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging

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Neural Regeneration Research 2025年第11期20卷 3144-3150页

作者： Holly Flyger Samantha J.Holdsworth Alistair J.Gunn Laura Bennet hamid Abbasi Mātai Medical Research Institute Tairāwhiti GisborneNew Zealand Department of Anatomy&Medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand Center for Brain Research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia

A multiscale material model for heterogeneous liquid droplets in solid soft composites

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Frontiers of Structural and Civil Engineering 2021年第5期15卷 1292-1299页

作者： hamid GHASEMI Department of Mechanical Engineering Arak University of TechnologyArak 38181-41167Iran

Liquid droplets in solid soft composites have been attracting increasing attention in biological *** contrary with conventional composites,which are made of solid elastic inclusions,available material models for composites including liquid droplets are for highly idealized configurations and do not include all material real *** are also all deterministic and do not address the uncertainties arising from droplet radius,volume fraction,dispersion and *** research revisits the available models for liquid droplets in solid soft composites and presents a multiscale computational material model to determine their elastic moduli,considering nearly all relevant uncertainties and heterogeneities at different length *** effects of surface tension at droplets interface,their volume fraction,size,size polydispersity and agglomeration on elastic modulus,are *** micromechanical material models are incorporated into the presented computational *** results clearly indicate both softening and stiffening effects of liquid droplets and show that the model can precisely predict the effective properties of liquid droplets in solid soft composites.

关键词： liquid in solid soft composite computational modeling multiscale model heterogeneity

Application of consistent geometric decomposition theorem to dynamic finite element of 3D composite beam based on experimental and numerical analyses

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 675-689页

作者： Iman FATTAHI hamid Reza MIRDAMADI hamid ABDOLLAHI Department of Mechanical Engineering Isfahan University of TechnologyIsfahan ***Iran

Analyzing static and dynamic problems including composite structures has been of high significance in research efforts and industrial *** this article,equivalent single layer approach is utilized for dynamic finite element procedures of 3D composite beam as the building block of numerous composite *** this model,both displacement and strain fields are decomposed into cross-sectional and longitudinal components,called consistent geometric decomposition ***,the model is discretized using finite clement *** local coordinate systems and a global one are defined to decouple mechanical degrees of ***,from the viewpoint of consistent geometric decomposition theorem,the transformation and element mass matrices for those systems are introduced here for the first *** same decomposition idea can be used for developing element stiffiness ***,comprehensive validations are conducted for the theory against experimental and numerical results in two case studies and for various conditions.

关键词： composite beam dynamic finite element degrees of freedom coupling experimental validation numerical validation

Coal pillar mechanics of violent failure in U.S. Mines

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International Journal of Mining Science and Technology 2017年第3期27卷 387-392页

作者： Maleki hamid Maleki Technologies Inc. Spokane WA 99223 USA

This paper seeks to enhance the understanding that the horizontal stresses build up and release during coal pillar loading and unloading(post-failure) drawing upon three decades of observations, geomechanical monitoring and numerical modeling in bump-prone U.S. mines. The focus is on induced horizontal stress in mine pillars and surrounding strata as highly stressed pillars punch into the roof and floor, causing shear failure and buckling of strata; under stiff stratigraphic units of some western US mines, these events could be accompanied by violent failure of pillar cores. Pillar punching eventually results in tensile stresses at the base of the pillar, facilitating transition into the post-failure regime; this transition will be nonviolent if certain conditions are met, notably the presence of interbedded mudstones with low shear strength properties and proper mine designs for controlling seismicity and dynamic loads. The study clearly shows high confining stress build-up in coal pillars resulting in up to twice higher peak vertical stress and high strain energy accumulations in some western US mines in comparison with peak stresses predicted using common empirical pillar design methods. It is the unstable release of this strain energy that can cause significant damage resulting from pillar dilation and ground movements. These forces are much greater than the capacity of most common internal support systems, resulting in horizontal stressinduced roof falls locally, in mines under unremarkable far-field horizontal stress. Attention should be placed on pillar designs as increasing support density may prove to be ineffective. This mechanism is analyzed using field measurements and generic finite-difference stress analyses. The study confirms the higher load carrying capacity of confinement-controlled coal seams in comparison with structurally controlled coal seams. Such significant differences in confining stresses are not taken into account when estimating peak pil

关键词： Rockburst and coal bumps Field measurements Stress analysis Mechanics Horizontal stress

Parallel resonance type fault current limiting circuit breaker

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High Voltage 2020年第1期5卷 76-82页

作者： hamid Radmanesh Seyed hamid Fathi Electrical Engineering Department Shahid Sattari Aeronautical University of Science and TechnologyTehranIran Electrical Engineering Department Amirkabir University of TechnologyTehranIran

The main goal of this study is introducing a novel fault current limiter based on parallel resonance structure(PRFCL)for high voltage *** normal mode,the PRFCL reactor is short-circuited via a rectifier bridge DC output voltage and LC resonance tank shows negligible impedance in the *** a fault,the rectifier bridge switches are turned off,so that the parallel resonance LC tank connects to the line with high *** impedance of the resonance structure can limit the fault current,*** is shown that the suggested PRFCL can act as a breaker and opens the line during the fault *** order to show the suggested PRFCL abilities,MATLAB software is used to simulate the normal and fault *** addition,a scale-down prototype is implemented to confirm the simulation *** comparative study shows that PRFCL has acceptable performance in normal and current limiting operation modes.

关键词： period fault limiting

Assessment of fracture process in forta and polypropylene fiber-reinforced concrete using experimental analysis and digital image correlation

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Frontiers of Structural and Civil Engineering 2022年第12期16卷 1633-1652页

作者： Seyed hamid KALALI hamid ESKANDARI-NADDAF Seyed Ali EMAMIAN Department of Civil Engineering Hakim Sabzevari UniversitySabzevar ***Iran

This paper aims to characterize the evolution of the fracture process and the cracking behavior in fortaferro(FF)and polypropylene(PP)fiber-reinforced concrete under the uniaxial compressive loading using experimental analysis and digital image correlation(DIC)on the surface *** this purpose,6 mix designs,including two FF volume fractions of 0.10%,and 0.20%and three PP volume fractions of 0.20%,0.30%,and 0.40%,in addition to a control mix were evaluated according to compressive strength,modulus of elasticity,toughness index,and stress–strain *** influence of fibers on the microstructural texture of specimens was analyzed by scanning electron microscope(SEM)*** show that FF fiber-reinforced concrete specimens demonstrated increased ductility and strength compared to PP *** results revealed that the major crack and fracture appeared at the peak load of the control specimen due to brittleness and sudden gain of large lateral strain,while a gradual increase in micro-crack quantity at 75%of peak load was observed in the fiber specimens,which thenbegan to connect with each other up to the final *** accuracy of the results supports DIC as a reliable alternative for the characterization of the fracture process in fiber-reinforced concrete.

关键词： fiber-reinforced concrete forta-ferro and polypropylene fiber fracture process cracking behavior digital image correlation

Entanglement detection in the mixed-spin Ising–XY model

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Chinese Physics B 2016年第3期25卷 73-83页

作者： hamid Arian Zad Department of Physics Shahrood University of Technology

In the present work, we initially verify anisotropy effect on the heat capacity of a mixed-three-spin （1/2,1,1/2） system （where spins （1/2,1/2） have XY interaction and spins （1,1/2） have Ising interaction together） at finite temperatures, then, the pairwise entanglement for spins （1/2,1/2）, by means of negativity （as a measure of entanglement） as a function of the temperature T, homogeneous magnetic field B, and anisotropy parameter 7 is investigated. In addition, we show that one can find magnetic phase transition points for the spins （1/2,1/2） at finite temperatures and understand properly their behavior with respect to the magnetic field and the anisotropy parameter, via the negativity function. An interval of the magnetic field from the negativity diagram of the spins （1/2,1/2） is presented in which quantum phase transition occurs for the tripartite mixed-three-spin system. FinaUy, some new interesting entanglement witnesses are introduced by using non-degenerate perturbation theory for the mixed-three-spin system.

关键词： anisotropy negativity heat capacity witness

A new method for the mononitration of phenol derivatives by poly(4-vinylpyridinium nitrate) and silica sulfuric acid under mild conditions

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Chinese Chemical Letters 2012年第4期23卷 458-461页

作者： hamid Goudarziafshar Department of Chemistry Faculty of ScienceIlam UniversityP.O.Box 69315516IlamIran

This procedure works efficiently for high selective mono nitration of phenol and substituted phenol to corresponding nitro compounds in moderate to high yield using poly（4-vinylpyridinium nitrate） and silica sulfuri... 详细信息

关键词： Poly(4-vinylpyridinium nitrate) Silica sulfuric acid Phenol Nitration

Divergence and flutter instability of magneto-thermo-elastic C-BN hetero-nanotubes conveying fluid

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Acta Mechanica Sinica 2020年第2期36卷 381-396页

作者： hamid M.Sedighi Mechanical Engineering Department Faculty of EngineeringShahid Chamran University of AhvazAhvaz 61357-43337Iran Drilling Center of Excellence and Research Center Shahid Chamran University of AhvazAhvaz 61357-43337Iran

On the basis of finite element analysis,an eigenvalue problem is performed to examine the vibrational characteristics of a hetero-nanotube made of carbon(C)and boron nitride(BN)nanotubes in magnetic and thermal *** incorporating the assumption of nonlocal elasticity theory,the size-dependent behavior of the considered structure is also taken into *** obtained results demonstrate that the onset of the divergence and flutter instabilities may be postponed by exploiting a hetero-nanotube rather than a uniform one composed of carbon ***,it is exhibited that,in the presence of fluid flow,the mode shape configuration of nanotubes may be different from those of classical modes and therefore the later one should not be utilized in the dynamic analysis of fluid-conveying ***,it is shown that,as the temperature decreases,the natural frequencies of the system decrease in high temperature conditions and increase for the case of room temperature.

关键词： Hetero-nanotube Fluid-conveying Magnetic flow Nonlocal elasticity Thermal environment