scholarly journals Investigating the Ubiquitous Presence of Nanometric Water Films on Surfaces

2021 ◽  
Author(s):  
Sergio Santos ◽  
Carlo Alberto Amadei ◽  
Chia-Yun Lai ◽  
Tuza Olukan ◽  
Jin-You Lu ◽  
...  
Keyword(s):  
Water Films ◽  
Ubiquitous Presence

New Design for a Differentially Pumped Hydration Chamber for a Siemens IA

1971 ◽  
Vol 29 ◽  
pp. 44-45
Author(s):  
R. C. Moretz ◽  
G. G. Hausner ◽  
D. F. Parsons
Keyword(s):  
Electron Microscopy ◽  
Water Vapor ◽  
Electron Diffraction ◽  
Water Vapor Pressure ◽  
Biological Materials ◽  
Thin Membrane ◽  
Reliable System ◽  
System A ◽  
Water Films ◽  
Aperture Opening

Electron microscopy and diffraction of biological materials in the hydrated state requires the construction of a chamber in which the water vapor pressure can be maintained at saturation for a given specimen temperature, while minimally affecting the normal vacuum of the remainder of the microscope column. Initial studies with chambers closed by thin membrane windows showed that at the film thicknesses required for electron diffraction at 100 KV the window failure rate was too high to give a reliable system. A single stage, differentially pumped specimen hydration chamber was constructed, consisting of two apertures (70-100μ), which eliminated the necessity of thin membrane windows. This system was used to obtain electron diffraction and electron microscopy of water droplets and thin water films. However, a period of dehydration occurred during initial pumping of the microscope column. Although rehydration occurred within five minutes, biological materials were irreversibly damaged. Another limitation of this system was that the specimen grid was clamped between the apertures, thus limiting the yield of view to the aperture opening.

The Qur'an in the Novels of Naguib Mahfouz (in Arabic)

2014 ◽  
Vol 16 (3) ◽  
pp. 126-104
Author(s):  
M.A.S. Abdel Haleem
Keyword(s):  
Creative Writing ◽  
Nobel Prize ◽  
Literary Works ◽  
Modern Education ◽  
Ubiquitous Presence ◽  
Structural Aspects ◽  
Artistic Talent ◽  
Naguib Mahfouz

With a rich, productive career spanning over 60 years, culminating in the award of the Nobel Prize for Literature in 1988, Naguib Mahfouz's literary works have naturally attracted numerous studies and critiques. These studies have covered a great many aspects of Mahfouz's creative writing, but, perhaps because of the secular, modern education Mahfouz received (both at school and in the Department of Philosophy in Cairo University), and his personal lifestyle, they have concentrated on the socialist, materialist, and structural aspects of his work. Perhaps because of this, one important aspect of his writing has largely escaped attention: his artistic use of the language of the Qur'an. Mahfouz does not signal that a given phrase or reference is Qur'anic, leaving it to blend with the text, and making it easy to miss the fact that the Qur'an played any part in Mahfouz's use of language. However, to a reader who knows the Qur'an by heart the presence of Qur'anic language in his works is obvious, and equally obvious is Mahfouz's artistic talent in using it. Eventually, he himself announced at the end of his life that he had always had an intimate interest in the Qur'an, read it daily, and benefited from it. This article seeks to demonstrate the ubiquitous presence of Qur'anic language in Mahfouz's works, and the skill and subtlety with which he used it.

Thinning air–water films stabilized by bacterial particles

2021 ◽  
Author(s):  
Song Wu ◽  
Yuehua Yang ◽  
Hongyuan Jiang
Keyword(s):  
Water Films

A large portion of the astrocyte proteome is dedicated to perivascular endfeet, including critical components of the electron transport chain

2021 ◽  
pp. 0271678X2110041
Author(s):  
Jesse A Stokum ◽  
Bosung Shim ◽  
Weiliang Huang ◽  
Maureen Kane ◽  
Jesse A Smith ◽  
...  
Keyword(s):  
Electron Transport ◽  
Electron Transport Chain ◽  
Glycogen Storage ◽  
Subcellular Compartment ◽  
Diffusion Limited ◽  
Transport Chain ◽  
Critical Components ◽  
And Diffusion ◽  
Ubiquitous Presence ◽  
Astrocyte Endfeet

The perivascular astrocyte endfoot is a specialized and diffusion-limited subcellular compartment that fully ensheathes the cerebral vasculature. Despite their ubiquitous presence, a detailed understanding of endfoot physiology remains elusive, in part due to a limited understanding of the proteins that distinguish the endfoot from the greater astrocyte body. Here, we developed a technique to isolate astrocyte endfeet from brain tissue, which was used to study the endfoot proteome in comparison to the astrocyte somata. In our approach, brain microvessels, which retain their endfoot processes, were isolated from mouse brain and dissociated, whereupon endfeet were recovered using an antibody-based column astrocyte isolation kit. Our findings expand the known set of proteins enriched at the endfoot from 10 to 516, which comprised more than 1/5th of the entire detected astrocyte proteome. Numerous critical electron transport chain proteins were expressed only at the endfeet, while enzymes involved in glycogen storage were distributed to the somata, indicating subcellular metabolic compartmentalization. The endfoot proteome also included numerous proteins that, while known to have important contributions to blood-brain barrier function, were not previously known to localize to the endfoot. Our findings highlight the importance of the endfoot and suggest new routes of investigation into endfoot function.

scholarly journals Arginine Is a Critical Substrate for the Pathogenesis of Pseudomonas aeruginosa in Burn Wound Infections

mBio ◽  
2017 ◽  
Vol 8 (2) ◽  
Author(s):  
Jake Everett ◽  
Keith Turner ◽  
Qiuxian Cai ◽  
Vernita Gordon ◽  
Marvin Whiteley ◽  
...  
Keyword(s):  
Antimicrobial Agents ◽  
Hospital Setting ◽  
Multidrug Resistant ◽  
Burn Patients ◽  
Burn Wound ◽  
Burn Wounds ◽  
Resistant Strains ◽  
High Doses ◽  
Ubiquitous Presence

ABSTRACT Environmental conditions affect bacterial behavior and can greatly influence the course of an infection. However, the environmental cues that elicit bacterial responses in specific infection sites are relatively unknown. Pseudomonas aeruginosa is ubiquitous in nature and typically innocuous. However, it is also one of the most prevalent causes of fatal sepsis in burn wound patients. The aim of this study was to determine the impact of environmental factors, specifically the availability of arginine, on the pathogenesis of P. aeruginosa in burn wound infections. Comparison of burned versus noninjured tissue revealed that l-arginine (l-Arg) was significantly depleted in burn wounds as a consequence of elevated arginase produced by myeloid-derived suppressor cells. We also observed that l-Arg was a potent chemoattractant for P. aeruginosa, and while low concentrations of l-Arg increased P. aeruginosa’s swimming motility, high concentrations resulted in diminished swimming. Based on these observations, we tested whether the administration of exogenous l-Arg into the burn wound could attenuate the virulence of P. aeruginosa in thermally injured mice. Administration of l-Arg resulted in decreased P. aeruginosa spread and sepsis and increased animal survival. Taken together, these data demonstrate that the availability of environmental arginine greatly influences the virulence of P. aeruginosa in vivo and may represent a promising phenotype-modulating tool for future therapeutic avenues. IMPORTANCE Despite our growing understanding of the pathophysiology of burn wounds and the evolution of techniques and practices to manage infections, sepsis remains a significant medical concern for burn patients. P. aeruginosa continues to be a leader among all causes of bacteremic infections due to its tendency to cause complications in immunocompromised patients and its ubiquitous presence in the hospital setting. With the unforgiving emergence of multidrug-resistant strains, it is critical that alternative strategies to control or prevent septic infections in burn patients be developed in parallel with novel antimicrobial agents. In this study, we observed that administration of l-Arg significantly reduced bacterial spread and sepsis in burned mice infected with P. aeruginosa. Given the safety of l-Arg in high doses and its potential wound-healing benefits, this conditionally essential amino acid may represent a useful tool to modulate bacterial behavior in vivo and prevent sepsis in burn patients. IMPORTANCE Despite our growing understanding of the pathophysiology of burn wounds and the evolution of techniques and practices to manage infections, sepsis remains a significant medical concern for burn patients. P. aeruginosa continues to be a leader among all causes of bacteremic infections due to its tendency to cause complications in immunocompromised patients and its ubiquitous presence in the hospital setting. With the unforgiving emergence of multidrug-resistant strains, it is critical that alternative strategies to control or prevent septic infections in burn patients be developed in parallel with novel antimicrobial agents. In this study, we observed that administration of l-Arg significantly reduced bacterial spread and sepsis in burned mice infected with P. aeruginosa. Given the safety of l-Arg in high doses and its potential wound-healing benefits, this conditionally essential amino acid may represent a useful tool to modulate bacterial behavior in vivo and prevent sepsis in burn patients.

The deposition angle-dependent density of amorphous solid water films

2003 ◽  
Vol 118 (1) ◽  
pp. 364-372 ◽  
Author(s):  
Z. Dohnálek ◽  
Greg A. Kimmel ◽  
Patrick Ayotte ◽  
R. Scott Smith ◽  
Bruce D. Kay
Keyword(s):  
Amorphous Solid ◽  
Amorphous Solid Water ◽  
Water Films ◽  
Solid Water ◽  
Deposition Angle ◽  
Dependent Density
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