876 research outputs found
The U.S. Department of Defense Humanitarian Demining Training Center: A Center of Excellence
Humanitarian mine action (HMA) is a field known for its paradigm shifts. Just as technological advances create more efficient and less expensive alternatives to old products and methodologies, emerging technologies offer newer and safer ways to detect landmines. Integrating these advances into the HMA community and thereby the training curriculum, is one challenge faced by the staff of the U.S. Department of Defense Humanitarian Demining Training Center (HDTC)
Insulin-Secreting Pancreatic (Islet Cell) Carcinoma in a Cat
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72904/1/j.1939-1676.1992.tb00336.x.pd
Visualization of Epidermal Growth Factor Receptors in Human Epidermis
The localization of epidermal growth factor (EGF) receptors in normal human epidermis was examined with two independent experimental methods. The distribution of EGF receptor sites was studied using light microscopic autoradiography with [125I]EGF and direct immunocytochemical techniques with EGF receptor antibodies and protein A-colloidal gold complexes. Direct visualization by autoradiography indicated that the concentration of EGF receptors was greatest in the lower epidermal layers. Ultrastructural morphometric analysis of protein A-gold complexes showed that EGF receptors were primarily associated with the plasma membranes although intranuclear and cytoplasmic localization was also evident. This postembedment immunolocalization method also confirmed the relative differences in the number of EGF receptors found in individual epidermal layers (basalis > spinosum > granulosum corneum layers). This inverse relationship between numbers of EGF receptors and the degree of epidermal differentiation and/or keratinization may suggest a physiologic role for EGF in these processes in human epidermis
MODIS. Volume 1: MODIS level 1A software baseline requirements
This document describes the level 1A software requirements for the moderate resolution imaging spectroradiometer (MODIS) instrument. This includes internal and external requirements. Internal requirements include functional, operational, and data processing as well as performance, quality, safety, and security engineering requirements. External requirements include those imposed by data archive and distribution systems (DADS); scheduling, control, monitoring, and accounting (SCMA); product management (PM) system; MODIS log; and product generation system (PGS). Implementation constraints and requirements for adapting the software to the physical environment are also included
Brain responses reveal young infants’ sensitivity to when a social partner follows their gaze
Infants’ ability to follow another person's eye gaze has been studied extensively and is considered to be an important and early emerging social cognitive skill. However, it is not known whether young infants detect when a social partner follows their gaze to an object. This sensitivity might help infants in soliciting information from others and serve as an important basis for social learning. In this study, we used functional near-infrared spectroscopy (fNIRS) to measure 5-month-old infants’ frontal and temporal cortex responses during social interactions in which a social partner (virtual agent) either followed the infants’ gaze to an object (congruent condition) or looked to an object that the infant had not looked at before (incongruent condition). The fNIRS data revealed that a region in the left prefrontal cortex showed an increased response when compared to baseline during the congruent condition but not during the incongruent condition, suggesting that infants are sensitive to when someone follows their gaze. The findings and their implications for the development of early social cognition are discussed in relation to what is known about the brain processes engaged by adults during these kinds of social interactions
A photometric and spectroscopic investigation of star formation in the very young open cluster NGC6383
The very young open cluster NGC 6383 centered on the O-star binary HD 159176
is an interesting place for studying the impact of early-type stars with strong
radiation fields and powerful winds on the formation processes of low-mass
stars. To investigate this process, it is necessary to determine the
characteristics (age, presence, or absence of circumstellar material) of the
population of low-mass pre-main-sequence (PMS) stars in the cluster. We
obtained deep U B V (R I)_c H-alpha photometric data of the entire cluster as
well as medium-resolution optical spectroscopy of a subsample of X-ray selected
objects. Our spectroscopic data reveal only very weak H-alpha emission lines in
a few X-ray selected PMS candidates. We photometrically identify a number of
H-alpha emission candidates but their cluster membership is uncertain. We find
that the fainter objects in the field of view have a wide range of extinction
(up to A_V = 20), one X-ray selected OB star having A_V ~ 8. Our investigation
uncovers a population of PMS stars in NGC 6383 that are probably coeval with HD
159176. In addition, we detect a population of reddened objects that are
probably located at different depths within the natal molecular cloud of the
cluster. Finally, we identify a rather complex spatial distribution of H-alpha
emitters, which is probably indicative of a severe contamination by foreground
and background stars.Comment: Accepted for publication in Astronomy & Astrophysic
Long period variables in 47 Tuc: direct evidence for lost mass
We have identified 22 new variable red giants in 47 Tuc and determined
periods for another 8 previously known variables. All red giants redder than
V-I_c=1.8 are variable at the limits of our detection threshold, which
corresponds to delta V ~ 0.1 mag. This colour limit corresponds to a luminosity
log L/L_sun=3.15 and it is considerably below the tip of the RGB at log
L/L_sun=3.35. Linear non-adiabatic models without mass loss on the giant branch
can not reproduce the observed PL laws for the low amplitude pulsators. Models
that have undergone mass loss do reproduce the observed PL relations and they
show that mass loss of the order of 0.3 M_sun occurs along the RGB and AGB. The
linear pulsation periods do not agree well with the observed periods of the
large amplitude Mira variables, which pulsate in the fundamental mode. The
solution to this problem appears to be that the nonlinear pulsation periods in
these low mass stars are considerably shorter than the linear pulsation periods
due to a rearrangement of stellar structure caused by the pulsation. Both
observations and theory show that stars evolve up the RGB and first part of the
AGB pulsating in low order overtone modes, then switch to fundamental mode at
high luminosities.Comment: 11 pages, accepted for publication in A&
Neural Models of Normal and Abnormal Behavior: What Do Schizophrenia, Parkinsonism, Attention Deficit Disorder, and Depression Have in Common?
Defense Advanced Research Projects Agency and Office of Naval Research (N00014-95-1-0409); National Science Foundation (IRI-97-20333
Mutations in multidomain protein MEGF8 identify a Carpenter syndrome subtype associated with defective lateralization
Carpenter syndrome is an autosomal-recessive multiple-congenital-malformation disorder characterized by multisuture craniosynostosis and polysyndactyly of the hands and feet; many other clinical features occur, and the most frequent include obesity, umbilical hernia, cryptorchidism, and congenital heart disease. Mutations of RAB23, encoding a small GTPase that regulates vesicular transport, are present in the majority of cases. Here, we describe a disorder caused by mutations in multiple epidermal-growth-factor-like-domains 8 (MEGF8), which exhibits substantial clinical overlap with Carpenter syndrome but is frequently associated with abnormal left-right patterning. We describe five affected individuals with similar dysmorphic facies, and three of them had either complete situs inversus, dextrocardia, or transposition of the great arteries; similar cardiac abnormalities were previously identified in a mouse mutant for the orthologous Megf8. The mutant alleles comprise one nonsense, three missense, and two splice-site mutations; we demonstrate in zebrafish that, in contrast to the wild-type protein, the proteins containing all three missense alterations provide only weak rescue of an early gastrulation phenotype induced by Megf8 knockdown. We conclude that mutations in MEGF8 cause a Carpenter syndrome subtype frequently associated with defective left-right patterning, probably through perturbation of signaling by hedgehog and nodal family members. We did not observe any subject with biallelic loss-of function mutations, suggesting that some residual MEGF8 function might be necessary for survival and might influence the phenotypes observed
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