For the moment, let's try collaboration

1981 ◽  
Vol 26 (8) ◽  
pp. 652-652
Author(s):  
Morris J. Paulson
Keyword(s):  
Author(s):  
A. V. Crewe

The high resolution STEM is now a fact of life. I think that we have, in the last few years, demonstrated that this instrument is capable of the same resolving power as a CEM but is sufficiently different in its imaging characteristics to offer some real advantages.It seems possible to prove in a quite general way that only a field emission source can give adequate intensity for the highest resolution^ and at the moment this means operating at ultra high vacuum levels. Our experience, however, is that neither the source nor the vacuum are difficult to manage and indeed are simpler than many other systems and substantially trouble-free.


Author(s):  
Burton B. Silver

Sectioned tissue rarely indicates evidence of what is probably a highly dynamic state of activity in mitochondria which have been reported to undergo a variety of movements such as streaming, divisions and coalescence. Recently, mitochondria from the rat anterior pituitary have been fixed in a variety of configurations which suggest that conformational changes were occurring at the moment of fixation. Pinocytotic-like vacuoles which may be taking in or expelling materials from the surrounding cell medium, appear to be forming in some of the mitochondria. In some cases, pores extend into the matrix of the mitochondria. In other forms, the remains of what seems to be pinched off vacuoles are evident in the mitochondrial interior. Dense materials, resembling secretory droplets, appear at the junction of the pores and the cytoplasm. The droplets are similar to the secretory materials commonly identified in electron micrographs of the anterior pituitary.


Author(s):  
J. S. Wall

The forte of the Scanning transmission Electron Microscope (STEM) is high resolution imaging with high contrast on thin specimens, as demonstrated by visualization of single heavy atoms. of equal importance for biology is the efficient utilization of all available signals, permitting low dose imaging of unstained single molecules such as DNA.Our work at Brookhaven has concentrated on: 1) design and construction of instruments optimized for a narrow range of biological applications and 2) use of such instruments in a very active user/collaborator program. Therefore our program is highly interactive with a strong emphasis on producing results which are interpretable with a high level of confidence.The major challenge we face at the moment is specimen preparation. The resolution of the STEM is better than 2.5 A, but measurements of resolution vs. dose level off at a resolution of 20 A at a dose of 10 el/A2 on a well-behaved biological specimen such as TMV (tobacco mosaic virus). To track down this problem we are examining all aspects of specimen preparation: purification of biological material, deposition on the thin film substrate, washing, fast freezing and freeze drying. As we attempt to improve our equipment/technique, we use image analysis of TMV internal controls included in all STEM samples as a monitor sensitive enough to detect even a few percent improvement. For delicate specimens, carbon films can be very harsh-leading to disruption of the sample. Therefore we are developing conducting polymer films as alternative substrates, as described elsewhere in these Proceedings. For specimen preparation studies, we have identified (from our user/collaborator program ) a variety of “canary” specimens, each uniquely sensitive to one particular aspect of sample preparation, so we can attempt to separate the variables involved.


Author(s):  
Oscar D. Guillamondegui

Traumatic brain injury (TBI) is a serious epidemic in the United States. It affects patients of all ages, race, and socioeconomic status (SES). The current care of these patients typically manifests after sequelae have been identified after discharge from the hospital, long after the inciting event. The purpose of this article is to introduce the concept of identification and management of the TBI patient from the moment of injury through long-term care as a multidisciplinary approach. By promoting an awareness of the issues that develop around the acutely injured brain and linking them to long-term outcomes, the trauma team can initiate care early to alter the effect on the patient, family, and community. Hopefully, by describing the care afforded at a trauma center and by a multidisciplinary team, we can bring a better understanding to the armamentarium of methods utilized to treat the difficult population of TBI patients.


1982 ◽  
Author(s):  
Carol Zahner ◽  
M. Stephen Kaminaka

Chelovek RU ◽  
2020 ◽  
pp. 18-53
Author(s):  
Sergei Avanesov ◽  

Abstract. The article analyzes the autobiography of the famous Russian philosopher, theologian and scientist Pavel Florensky, as well as those of his texts that retain traces of memories. According to Florensky, the personal biography is based on family history and continues in children. He addresses his own biography to his children. Memories based on diary entries are designed as a memory diary, that is, as material for future memories. The past becomes actual in autobiography, turns into a kind of present. The past, from the point of view of its realization in the present, gains meaning and significance. The au-thor is active in relation to his own past, transforming it from a collection of disparate facts into a se-quence of events. A person can only see the true meaning of such events from a great distance. Therefore, the philosopher remembers not so much the circumstances of his life as the inner impressions of the en-counter with reality. The most powerful personality-forming experiences are associated with childhood. Even the moment of birth can decisively affect the character of a person and the range of his interests. The foundations of a person's worldview are laid precisely in childhood. Florensky not only writes mem-oirs about himself, but also tries to analyze the problems of time and memory. A person is immersed in time, but he is able to move into the past through memory and into the future through faith. An autobi-ography can never be written to the end because its author lives on. However, reaching the depths of life, he is able to build his path in such a way that at the end of this path he will unite with the fullness of time, with eternity.


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