scholarly journals Magnetite pollution nanoparticles in the human brain

2016 ◽  
Vol 113 (39) ◽  
pp. 10797-10801 ◽  
Author(s):  
Barbara A. Maher ◽  
Imad A. M. Ahmed ◽  
Vassil Karloukovski ◽  
Donald A. MacLaren ◽  
Penelope G. Foulds ◽  
...  
Keyword(s):  
High Temperature ◽  
Transition Metal ◽  
Human Brain ◽  
Airborne Particulate Matter ◽  
Magnetic Behavior ◽  
Redox Activity ◽  
Internal Source ◽  
The Brain ◽  
Iron Bearing ◽  
Particulate Matter Pollution

Biologically formed nanoparticles of the strongly magnetic mineral, magnetite, were first detected in the human brain over 20 y ago [Kirschvink JL, Kobayashi-Kirschvink A, Woodford BJ (1992) Proc Natl Acad Sci USA 89(16):7683–7687]. Magnetite can have potentially large impacts on the brain due to its unique combination of redox activity, surface charge, and strongly magnetic behavior. We used magnetic analyses and electron microscopy to identify the abundant presence in the brain of magnetite nanoparticles that are consistent with high-temperature formation, suggesting, therefore, an external, not internal, source. Comprising a separate nanoparticle population from the euhedral particles ascribed to endogenous sources, these brain magnetites are often found with other transition metal nanoparticles, and they display rounded crystal morphologies and fused surface textures, reflecting crystallization upon cooling from an initially heated, iron-bearing source material. Such high-temperature magnetite nanospheres are ubiquitous and abundant in airborne particulate matter pollution. They arise as combustion-derived, iron-rich particles, often associated with other transition metal particles, which condense and/or oxidize upon airborne release. Those magnetite pollutant particles which are <∼200 nm in diameter can enter the brain directly via the olfactory bulb. Their presence proves that externally sourced iron-bearing nanoparticles, rather than their soluble compounds, can be transported directly into the brain, where they may pose hazard to human health.

Electron energy loss near edge structures of intermetallic alloys and grain boundaries in NiAl

1996 ◽  
Vol 54 ◽  
pp. 522-523
Author(s):  
G.A. Botton ◽  
C.J. Humphreys
Keyword(s):  
High Temperature ◽  
Transition Metal ◽  
Energy Loss ◽  
Grain Boundaries ◽  
Industrial Applications ◽  
Edge Structure ◽  
Structural Applications ◽  
Yield Behaviour ◽  
Late Transition ◽  
Metal Aluminides

Transition metal aluminides are of great potential interest for high temperature structural applications. Although these materials exhibit good mechanical properties at high temperature, their use in industrial applications is often limited by their intrinsic room temperature brittleness. Whilst this particular yield behaviour is directly related to the defect structure, the properties of the defects (in particular the mobility of dislocations and the slip system on which these dislocations move) are ultimately determined by the electronic structure and bonding in these materials. The lack of ductility has been attributed, at least in part, to the mixed bonding character (metallic and covalent) as inferred from ab-initio calculations. In this work, we analyse energy loss spectra and discuss the features of the near edge structure in terms of the relevant electronic states in order to compare the predictions on bonding directly with spectroscopic experiments. In this process, we compare spectra of late transition metal (TM) to early TM aluminides (FeAl and TiAl) to assess whether differences in bonding can also be detected. This information is then discussed in terms of bonding changes at grain boundaries in NiAl.

Frontier concept of rabi chip for intelligent humanoid

2018 ◽  
Vol 1 (2) ◽  
Author(s):  
Preecha Yupapin ◽  
Amiri I. S. ◽  
Ali J. ◽  
Ponsuwancharoen N. ◽  
Youplao P.
Keyword(s):  
Human Brain ◽  
Brain Function ◽  
Rabi Oscillation ◽  
Liquid Core ◽  
Brain Surface ◽  
Dipole Oscillation ◽  
On Chip ◽  
The Brain ◽  
Robotic Applications ◽  
Atom System

The sequence of the human brain can be configured by the originated strongly coupling fields to a pair of the ionic substances(bio-cells) within the microtubules. From which the dipole oscillation begins and transports by the strong trapped force, which is known as a tweezer. The tweezers are the trapped polaritons, which are the electrical charges with information. They will be collected on the brain surface and transport via the liquid core guide wave, which is the mixture of blood content and water. The oscillation frequency is called the Rabi frequency, is formed by the two-level atom system. Our aim will manipulate the Rabi oscillation by an on-chip device, where the quantum outputs may help to form the realistic human brain function for humanoid robotic applications.

TIMELESS BUILDINGS AND THE HUMAN BRAIN: The Effect of Spiritual Spaces on Human Brain Waves

2014 ◽  
Vol 8 (1) ◽  
pp. 133
Author(s):  
Sally M. Essawy ◽  
Basil Kamel ◽  
Mohamed S. Elsawy
Keyword(s):  
Human Brain ◽  
Case Studies ◽  
Spiritual Experience ◽  
Brain Wave ◽  
Human Comfort ◽  
Beliefs And Practices ◽  
Brain Waves ◽  
Space Design ◽  
State Of Mind ◽  
The Brain

Some buildings hold certain qualities of space design similar to those originated from nature in harmony with its surroundings. These buildings, mostly associated with religious beliefs and practices, allow for human comfort and a unique state of mind. This paper aims to verify such effect on the human brain. It concentrates on measuring brain waves when the user is located in several spots (coordinates) in some of these buildings. Several experiments are conducted on selected case studies to identify whether certain buildings affect the brain wave frequencies of their users or not. These are measured in terms of Brain Wave Frequency Charts through EEG Device. The changes identified on the brain were then translated into a brain diagram that reflects the spiritual experience all through the trip inside the selected buildings. This could then be used in architecture to enhance such unique quality.

Art and the Brain’s Reward System

2018 ◽  
Author(s):  
Henrik Hogh-Olesen
Keyword(s):  
Human Brain ◽  
Reward System ◽  
Human Existence ◽  
Brain Scans ◽  
System P ◽  
The Aesthetic ◽  
The Brain ◽  
Reward Circuit

Chapter 7 takes the investigation of the aesthetic impulse into the human brain to understand, first, why only we—and not our closest relatives among the primates—express ourselves aesthetically; and second, how the brain reacts when presented with aesthetic material. Brain scans are less useful when you are interested in the Why of aesthetic behavior rather than the How. Nevertheless, some brain studies have been ground-breaking, and neuroaesthetics offers a pivotal argument for the key function of the aesthetic impulse in human lives; it shows us that the brain’s reward circuit is activated when we are presented with aesthetic objects and stimuli. For why reward a perception or an activity that is evolutionarily useless and worthless in relation to human existence?

scholarly journals Is There a Brain Microbiome?

2021 ◽  
Vol 16 ◽  
pp. 263310552110187
Author(s):  
Christopher D Link
Keyword(s):  
Animal Models ◽  
Human Brain ◽  
Neurodegenerative Diseases ◽  
Ground Truth ◽  
Healthy Human ◽  
Strong Motivation ◽  
The Many ◽  
The Brain

Numerous studies have identified microbial sequences or epitopes in pathological and non-pathological human brain samples. It has not been resolved if these observations are artifactual, or truly represent population of the brain by microbes. Given the tempting speculation that resident microbes could play a role in the many neuropsychiatric and neurodegenerative diseases that currently lack clear etiologies, there is a strong motivation to determine the “ground truth” of microbial existence in living brains. Here I argue that the evidence for the presence of microbes in diseased brains is quite strong, but a compelling demonstration of resident microbes in the healthy human brain remains to be done. Dedicated animal models studies may be required to determine if there is indeed a “brain microbiome.”

A bigger brain for a more complex environment

2020 ◽  
Vol 31 (8) ◽  
pp. 803-816
Author(s):  
Umberto di Porzio
Keyword(s):  
Human Brain ◽  
Cognitive Abilities ◽  
Molecular Genetic ◽  
Adult Size ◽  
Genetic Changes ◽  
Cultural Challenges ◽  
Birth Canal ◽  
Newborn Brain ◽  
Neuronal Interactions ◽  
The Brain

AbstractThe environment increased complexity required more neural functions to develop in the hominin brains, and the hominins adapted to the complexity by developing a bigger brain with a greater interconnection between its parts. Thus, complex environments drove the growth of the brain. In about two million years during hominin evolution, the brain increased three folds in size, one of the largest and most complex amongst mammals, relative to body size. The size increase has led to anatomical reorganization and complex neuronal interactions in a relatively small skull. At birth, the human brain is only about 20% of its adult size. That facilitates the passage through the birth canal. Therefore, the human brain, especially cortex, develops postnatally in a rich stimulating environment with continuous brain wiring and rewiring and insertion of billions of new neurons. One of the consequence is that in the newborn brain, neuroplasticity is always turned “on” and it remains active throughout life, which gave humans the ability to adapt to complex and often hostile environments, integrate external experiences, solve problems, elaborate abstract ideas and innovative technologies, store a lot of information. Besides, hominins acquired unique abilities as music, language, and intense social cooperation. Overwhelming ecological, social, and cultural challenges have made the human brain so unique. From these events, as well as the molecular genetic changes that took place in those million years, under the pressure of natural selection, derive the distinctive cognitive abilities that have led us to complex social organizations and made our species successful.

scholarly journals Reactive plasma cleaning and restoration of transition metal dichalcogenide monolayers

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Daniil Marinov ◽  
Jean-François de Marneffe ◽  
Quentin Smets ◽  
Goutham Arutchelvan ◽  
Kristof M. Bal ◽  
...  
Keyword(s):  
High Temperature ◽  
Transition Metal ◽  
Field Effect Transistors ◽  
Removal Rate ◽  
2D Materials ◽  
Scale Up ◽  
Transition Metal Dichalcogenides ◽  
Chemical Properties ◽  
Plasma Cleaning ◽  
Transition Metal Dichalcogenide

AbstractThe cleaning of two-dimensional (2D) materials is an essential step in the fabrication of future devices, leveraging their unique physical, optical, and chemical properties. Part of these emerging 2D materials are transition metal dichalcogenides (TMDs). So far there is limited understanding of the cleaning of “monolayer” TMD materials. In this study, we report on the use of downstream H2 plasma to clean the surface of monolayer WS2 grown by MOCVD. We demonstrate that high-temperature processing is essential, allowing to maximize the removal rate of polymers and to mitigate damage caused to the WS2 in the form of sulfur vacancies. We show that low temperature in situ carbonyl sulfide (OCS) soak is an efficient way to resulfurize the material, besides high-temperature H2S annealing. The cleaning processes and mechanisms elucidated in this work are tested on back-gated field-effect transistors, confirming that transport properties of WS2 devices can be maintained by the combination of H2 plasma cleaning and OCS restoration. The low-damage plasma cleaning based on H2 and OCS is very reproducible, fast (completed in a few minutes) and uses a 300 mm industrial plasma etch system qualified for standard semiconductor pilot production. This process is, therefore, expected to enable the industrial scale-up of 2D-based devices, co-integrated with silicon technology.

scholarly journals Tackling Dysfunction of Mitochondrial Bioenergetics in the Brain

2021 ◽  
Vol 22 (15) ◽  
pp. 8325
Author(s):  
Paola Zanfardino ◽  
Stefano Doccini ◽  
Filippo M. Santorelli ◽  
Vittoria Petruzzella
Keyword(s):  
Human Brain ◽  
Basic Function ◽  
Mitochondrial Proteome ◽  
Novel Proteins ◽  
Mitochondrial Functions ◽  
Organ Specific ◽  
Oxphos System ◽  
Mitochondrial Defects ◽  
Energy Dependent ◽  
The Brain

Oxidative phosphorylation (OxPhos) is the basic function of mitochondria, although the landscape of mitochondrial functions is continuously growing to include more aspects of cellular homeostasis. Thanks to the application of -omics technologies to the study of the OxPhos system, novel features emerge from the cataloging of novel proteins as mitochondrial thus adding details to the mitochondrial proteome and defining novel metabolic cellular interrelations, especially in the human brain. We focussed on the diversity of bioenergetics demand and different aspects of mitochondrial structure, functions, and dysfunction in the brain. Definition such as ‘mitoexome’, ‘mitoproteome’ and ‘mitointeractome’ have entered the field of ‘mitochondrial medicine’. In this context, we reviewed several genetic defects that hamper the last step of aerobic metabolism, mostly involving the nervous tissue as one of the most prominent energy-dependent tissues and, as consequence, as a primary target of mitochondrial dysfunction. The dual genetic origin of the OxPhos complexes is one of the reasons for the complexity of the genotype-phenotype correlation when facing human diseases associated with mitochondrial defects. Such complexity clinically manifests with extremely heterogeneous symptoms, ranging from organ-specific to multisystemic dysfunction with different clinical courses. Finally, we briefly discuss the future directions of the multi-omics study of human brain disorders.

Oxygen-Storage Materials to Stabilize the Oxygen Redox Activity of Three-Layered Sodium Transition Metal Oxides

2021 ◽  
pp. 7804-7811
Author(s):  
Mariya L. Kalapsazova ◽  
Krassimir L. Kostov ◽  
Rositsa R. Kukeva ◽  
Ekaterina N. Zhecheva ◽  
Radostina K. Stoyanova
Keyword(s):  
Transition Metal ◽  
Metal Oxides ◽  
Transition Metal Oxides ◽  
Oxygen Storage ◽  
Redox Activity ◽  
Storage Materials

MAGNETIC BEHAVIOR OF IRON IONS IN THE P2O5·CaO GLASS MATRIX

2003 ◽  
Vol 17 (24) ◽  
pp. 1271-1275 ◽  
Author(s):  
I. ARDELEAN ◽  
C. ANDRONACHE ◽  
P. PǍŞCUŢǍ
Keyword(s):  
Magnetic Susceptibility ◽  
High Temperature ◽  
Magnetic Moment ◽  
Glass Matrix ◽  
Magnetic Behavior ◽  
Iron Ions ◽  
Ion Content ◽  
Dipole Interactions ◽  
Valence States ◽  
Temperature Susceptibility

The temperature dependence of the magnetic susceptibility of x Fe 2 O 3·(100-x)-[ P 2 O 5· CaO ] glasses with 0<x≤50 mol % have been investigated. These data revealed that the valence states and the distribution of iron ions in the glass matrix depend on the Fe 2 O 3 content. For the glasses with x≤1 mol % only Fe 3+ ions are evidenced. In the case of the glasses with 3≤x≤35 mol % both Fe 3+ and Fe 2 ions co-exist in the P 2 O 5· CaO glass matrix, the Fe 2+ ion content is higher than that of the Fe 3+ ions for glasses with x≥10 mol %. For the glasses with x>35 mol %, the evaluated values of the μ eff indicate either the presence of Fe + ions or the coordination influence on the magnetic moment of iron ions, but the presence of small quantities of the antiferromagnetic or ferrimagnetic interactions between iron ions in studied temperature range cannot be excluded. The high temperature susceptibility results indicate that the iron ions are isolated or participate in dipole-dipole interactions for glasses with x≤35 mol % and are antiferromagnetically coupled for higher contents of Fe 2 O 3.

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