نتایج جستجو برای: microgravity

تعداد نتایج: 3241  

1999
Joel A Silver Daniel J Kane

Diode laser absorption spectroscopy provides a direct method of determinating species concentration and local gas temperature in combustion flames. Under microgravity conditions, diode lasers are particularly suitable, given their compact size, low mass and low power requirements. The development of diode laser-based sensors for gas detection in microgravity is presented, detailing measurements...

2015
Jose MESEGUER

In this paper the influence of an axial microgravity on the dynamic stability of axisymmetric slender liquid bridges between unequal disks is numerically studied by using a one-dimensional theory. The breaking of such liquid configurations is analyzed and the dependence of some overall characteristics of the breaking process on the value of axial microgravity, the geometry and the volume of the...

2017
Jade Q. Clement

Crewmembers of space flights commonly experience certain health condition changes such as immune system dysregulation, musculoskeletal changes (e.g., significant bone and muscle loss), and neurological alterations. Since the space exploration of the 1960s and 1970s, physiological changes in several organ systems due to weightlessness have been identified. Some of the adverse effects are a decli...

Purpose: Microgravity causes major changes in various systems of the body in space, such as shift in cerebrospinal fluid, decreased red blood cells count, and electrolyte loss. These complications are very important in space and we should find new approaches to prevent the side effects of microgravity in astronauts. Materials and Methods: This experimental study was conducted on 21 adult ma...

Journal: :Applied and environmental microbiology 1997
A Fang D L Pierson D W Koenig S K Mishra A L Demain

Production of the antibacterial polypeptide microcin B17 (MccB17) by Escherichia coli ZK650 was inhibited by simulated microgravity. The site of MccB17 accumulation was found to be different, depending on whether the organism was grown in shaking flasks or in rotating bioreactors designed to establish a simulated microgravity environment. In flasks, the accumulation was cellular, but in the rea...

2006
Ben Randall

Physiology in microgravity is a challenging field of research because of limited resources. Though humans have been in space for 50 years most meaningful data has been collected only within the last 15 years. While expensive studies with small sample sizes make obtaining and interpreting data difficult, some general conclusions about the human physiological response to microgravity can be drawn...

Journal: :Physiological research 2012
P Skrobánek M Baranovská B Sárniková M Zeman M Okuliarová

The aim of this study was to investigate the effects of long-term stay of Japanese quail in simulated microgravity on some sexual features of males. As a model for simulating microgravity exposure of birds in laboratory conditions was used hypodynamia. The mean left testis weight in males reared under hypodynamia from day 3 up to 180 days of age was lower than that of control (P<0.05), but the ...

2009
Carsten Güttler Jürgen Blum Joshua E. Colwell René Weidling Daniel Heißelmann

Low-velocity collisions play a fundamental role in various astrophysical environments like protoplanetary disks (planet formation) or the Saturnian rings (e.g. dynamics and stability). These collisions are likely to occur at velocities in the cm s−1 range and below, and a satisfactory experimental realization of the lowest velocities is so far not possible even in microgravity environments like...

2003
Yasuaki Kawai Mitsuru Doi Akira Setogawa Reiko Shimoyama Keigo Ueda Yasumasa Asai Kyoko Tatebayashi

After centuries of wonder, human being finally realized the decisive possibility of going to the moon a little more than 50 years ago, and in 1969 this became a reality, no longer a dream. The human body, however, is designed to live under 1 g as on Earth. Thus, it is important to understand what happens in the human body under microgravity in order to make rapid progress in space development. ...

1996
Gary L. Gilliland Michael Tung Jane Ladner

The NIST/NASA/CARB Biological Macromolecule Crystallization Database (BMCD), NIST Standard Reference Database 21, contains crystal data and crystallization conditions for biological macromolecules. The database entries include data abstracted from published crystallographic reports. Each entry consists of information describing the biological macromolecule crystallized and crystal data and the ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید