618 research outputs found
Coastal zone management
A panel of federal and state representatives concerned with coastal zone affairs discussed their problems in this area. In addition, several demonstrations of the application of remote sensing technology to coastal zone management were described. These demonstrations were performed by several agencies in a variety of geographical areas
Marine resources and ocean surveys
Application of ERTS-1 remotely sensed multispectral imagery to marine resources and oceanic observations and surveys - Conferenc
To be or not to be: the case of the hot WHIM absorption in the blazar PKS 2155-304 sight line
The cosmological missing baryons at z 5.5
K) phase of the warm hot intergalactic medium (WHIM). While the hot
WHIM is hard to detect due to its high ionisation level, the warm (T ≲
105.5 K) phase of the WHIM has been very robustly detected in
the far-ultraviolet (FUV) band. We adopted the assumption that the hot
and warm WHIM phases are co-located and therefore used the FUV-detected
warm WHIM as a tracer for the cosmologically interesting hot WHIM. We
performed an X-ray follow-up in the sight line of the blazar PKS
2155-304 at the redshifts where previous FUV measurements of O VI, Si
IV, and broad Lyman-alpha (BLA) absorption have indicated the existence
of the warm WHIM. We looked for the O VII Heα and O VIII Lyα absorption
lines, the most likely hot WHIM tracers. Despite the very large exposure
time (≈1 Ms), the Reflection Grating Spectrometer unit 1 (RGS1)
on-board XMM-Newton data yielded no significant detection which
corresponds to upper limits of log N(O VII(cm-2)) ≤ 14.5-15.2 and log N(O VIII(cm-2))
≤ 14.5-15.2. An analysis of the data obtained with the combination of
the Low Energy Transmission Grating (LETG) and the High Resolution
Camera (HRC) on-board Chandra yielded consistent results. However, the
data obtained with the LETG, combined with the Advanced CCD Imaging
Spectrometer (ACIS) lead to the detection of an feature resembling an
absorption line at λ ≈ 20 Å at simple one-parameter confidence level of
3.7σ, consistent with several earlier LETG/ACIS reports. Given the high
statistical quality of the RGS1 data, the possibility of RGS1
accidentally missing the true line at λ ̃ 20 Å is very low: 0.006%.
Neglecting this, the LETG/ACIS detection can be interpreted as Lyα
transition of O VIII at one of the redshifts (z ≈ 0.054) of FUV-detected
warm WHIM. Given the very convincing X-ray spectral evidence for and
against the existence of the λ ̃ 20 Å feature, we cannot conclude
whether or not it is a true astrophysical absorption line. Considering
cosmological simulations, the probability of the LETG/ACIS λ ̃ 20 Å
feature being due to the astrophysical O VIII absorber co-located with
the FUV-detected O VI absorber is at the very low level of ≲0.1%. We
cannot completely rule out the very unlikely possibility that the
LETG/ACIS 20 Ã… feature is due to a transient event located close to the
blazar. </p
To be or not to be : the case of the hot WHIM absorption in the blazar PKS 2155-304 sight line
The cosmological missing baryons at z <1 most likely hide in the hot (T greater than or similar to 10(5.5) K) phase of the warm hot intergalactic medium (WHIM). While the hot WHIM is hard to detect due to its high ionisation level, the warm (T less than or similar to 10(5.5) K) phase of the WHIM has been very robustly detected in the far-ultraviolet (FUV) band. We adopted the assumption that the hot and warm WHIM phases are co-located and therefore used the FUV-detected warm WHIM as a tracer for the cosmologically interesting hot WHIM. We performed an X-ray follow-up in the sight line of the blazar PKS 2155-304 at the redshifts where previous FUV measurements of O VI, Si IV, and broad Lyman-alpha (BLA) absorption have indicated the existence of the warm WHIM. We looked for the O VII Hc alpha and O VIII Ly alpha absorption lines, the most likely hot WHIM tracers. Despite the very large exposure time (approximate to 1 Ms), the Reflection Grating Spectrometer unit 1 (RGS1) on-board XMM-Newton data yielded no significant detection which corresponds to upper limits of log N(O VII (cm(-2)))Peer reviewe
Forum on immune digital twins: a meeting report
Medical digital twins are computational models of human biology relevant to a
given medical condition, which can be tailored to an individual patient,
thereby predicting the course of disease and individualized treatments, an
important goal of personalized medicine. The immune system, which has a central
role in many diseases, is highly heterogeneous between individuals, and thus
poses a major challenge for this technology. If medical digital twins are to
faithfully capture the characteristics of a patient's immune system, we need to
answer many questions, such as: What do we need to know about the immune system
to build mathematical models that reflect features of an individual? What data
do we need to collect across the different scales of immune system action? What
are the right modeling paradigms to properly capture immune system complexity?
In February 2023, an international group of experts convened in Lake Nona, FL
for two days to discuss these and other questions related to digital twins of
the immune system. The group consisted of clinicians, immunologists,
biologists, and mathematical modelers, representative of the interdisciplinary
nature of medical digital twin development. A video recording of the entire
event is available. This paper presents a synopsis of the discussions, brief
descriptions of ongoing digital twin projects at different stages of progress.
It also proposes a 5-year action plan for further developing this technology.
The main recommendations are to identify and pursue a small number of promising
use cases, to develop stimulation-specific assays of immune function in a
clinical setting, and to develop a database of existing computational immune
models, as well as advanced modeling technology and infrastructure
Effect of acute copper sulfate exposure on olfactory responses to amino acids and pheromones in goldfish (Carassius auratus)
Exposure of olfactory epithelium to environmentally relevant concentrations of copper disrupts olfaction in fish. To examine
the dynamics of recovery at both functional and morphological levels after acute copper exposure, unilateral exposure of goldfish olfactory epithelia to 100 μM CuSO4 (10 min) was followed by electro-olfactogram (EOG) recording and scanning electron microscopy. Sensitivity to amino acids (L-arginine
and L-serine), generally considered food-related odorants, recovered most rapidly (three days), followed by that to
catecholamines(3-O-methoxytyramine),bileacids(taurolithocholic acid) and the steroid pheromone, 17,20 -dihydroxy-4-pregnen-
3-one 20-sulfate, which took 28 days to reach full recovery. Sensitivity to the postovulatory pheromone prostaglandin F2R had
not fully recovered even at 28 days. These changes in sensitivity were correlated with changes in the recovery of ciliated and microvillous receptor cell types. Microvillous cells appeared largely unaffected by CuSO4 treatment. Cilia in
ciliated receptor neurones, however, appeared damaged one day post-treatment and were virtually absent after three days but
had begun to recover after 14 days. Together, these results support the hypothesis that microvillous receptor neurones detect amino acids whereas ciliated receptor neurones were not functional and are responsible for detection of social stimuli (bile acidsandpheromones).Furthermore, differences in sensitivity to copper may be due to different transduction pathways in
the different cell types
Mycorrhizal occurrence in willows in a northern freshwater wetland
Willows growing in a north central Michigan wetland were found to be ectomycorrhizal throughout the 1978 growing season on each of two sites (one water-saturated, one relatively drier). Each site was dominated by a mix of sedges ( Carex spp.) and willows ( Salix spp.). On both sites, phosphorus was added at two levels (20 or 200 kg P ha −1 ) to simulate potential inputs from the disposal of secondarily-treated municipal wastewater. The intensity of willow root infection was determined by scoring root tips on a 0 to 4 scale based on mantle-, intercellular hyphae-, and root epidermal cell characteristics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43474/1/11104_2005_Article_BF02184550.pd
A five-year multicenter study of the susceptibility of the Bacteroides fragilis group isolates to cephalosporins, cephamins, penicillins, clindamycin, and metronidazole in the United States
Over 2800 clinical strains of the Bacteroides fragilis group were collected during a 5-year period from ten geographically separate sites and tested for their susceptibility to various antimicrobial agents using a broth microdilution method. Among the cephalosporins, ceftizoxime was the most active (13% resistance) and importantly exhibited relatively equal activity against both B. fragilis species and non-B. fragilis species. Cefotaxime exhibited similar activity with an overall resistance rate of 18%. Both ceftriaxone and cefoperazone were appreciably less active cephalosporins especially against non-B. fragilis species. With regard to cephamycins, cefoxitin (MIC90, 32 [mu]g/ml) was more active than cefotetan (MIC90, [ges]256 [mu]g/ml) and cefmetazole (MIC90, 64 [mu]g/ml). Non-B. fragilis species were highly resistant to cefotetan and cefmetazole. Imipenem was highly active against all strains with the exception of four strains of B. fragilis. Ampicillin-sulbactam, amoxicillin-clavulanate, piperacillin-tazobactam, and cefoperazone-sulbactam were all highly active with resistance rates <2%. No resistance was detected to metronidazole, whereas 14% of isolates were resistant to clindamycin. When compared with other studies, these findings underscore the wide variability in susceptibility patterns reported nationwide and the need to continue monitoring these patterns to aid in choosing the most active compounds for therapy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31666/1/0000601.pd
- …