166 research outputs found
Case History — Performance Monitoring Success
The City Creek Center urban redevelopment project in Salt Lake City, Utah involved excavations up to 65 feet deep. Shoring systems included more than 29,000 square feet of anchored diaphragm walls, 100,000 square feet of soil nail walls, and 860 linear feet of underpinning. Detailed performance monitoring alerted the project team to unacceptable performance of an anchored diaphragm wall adjacent to an occupied twenty-five-story building on shallow foundations. This knowledge allowed the team to react quickly, stabilize the excavation, investigate the situation, and develop successful remedial measures. The diaphragm wall was reinforced with additional anchors and subgrade concrete struts, allowing the excavation to proceed with minimal delay and no damage to the adjacent building
Mass transfer from a giant star to a main sequence companion and its contribution to long-orbital-period blue stragglers
Binary population synthesis shows that mass transfer from a giant star to a
main-sequence (MS) companion may account for some observed long-orbital period
blue stragglers. However, little attention {\bf is paid to this blue straggler
formation scenario} as dynamical instability often happens when the mass donor
is a giant star. In this paper, we have studied the critical mass ratio,
, for dynamically stable mass transfer from a giant star to a MS
companion using detailed evolution calculations. The results show that a more
evolved star is generally less stable for Roche lobe overflow. Meanwhile,
almost linearly increases with the amount of the mass and angular
momentum {\bf lost} during mass transfer, but has little dependance on stellar
wind. To conveniently use the result, we give a fit of as a
function of the stellar radius at the onset of Roche lobe overflow and of the
mass transfer efficiency during the Roche lobe overflow.
To examine the formation of blue stragglers from mass transfer between giants
and MS stars, we have performed Monte Carlo simulations with various . {\bf The simulations show that some binaries with the mass donor on the
first giant branch may contribute to blue stragglers with obtained
in this paper but will not from previous . Meanwhile, from our
, blue stragglers from the mass transfer between an AGB star and a
MS companion may be more numerous and have a wider range of orbital periods
than those from the other .Comment: 16 pages, 17 figures. accepted by MNRA
Maine Gay Task Force Newsletter, Vol.3, No.06 (June 1976)
https://digitalcommons.usm.maine.edu/megtf/1014/thumbnail.jp
Maine Gay Task Force Newsletter, Vol.3, No.07 (July 1976)
https://digitalcommons.usm.maine.edu/megtf/1015/thumbnail.jp
A Search for Early Optical Emission from Short and Long Duration Gamma-ray Bursts
Gamma-ray bursts of short duration may harbor vital clues to the range of
phenomena producing bursts. However, recent progress from the observation of
optical counterparts has not benefitted the study of short bursts. We have
searched for early optical emission from six gamma-ray bursts using the ROTSE-I
telephoto array. Three of these events were of short duration, including GRB
980527 which is among the brightest short bursts yet observed. The data consist
of unfiltered CCD optical images taken in response to BATSE triggers delivered
via the GCN. For the first time, we have analyzed the entire 16 degree by 16
degree field covered for five of these bursts. In addition, we discuss a search
for the optical counterpart to GRB 000201, a well-localized long burst. Single
image sensitivities range from 13th to 14th magnitude around 10 s after the
initial burst detection, and 14 - 15.8 one hour later. No new optical
counterparts were discovered in this analysis suggesting short burst optical
and gamma-ray fluxes are uncorrelated.Comment: 8 pages, 2 figures, subm. to ApJ Let
Maine Gay Task Force Newsletter, Vol.3, No.03 (March 1976)
https://digitalcommons.usm.maine.edu/megtf/1011/thumbnail.jp
Maine Gay Task Force Newsletter, Vol.3, No.08 (August 1976)
https://digitalcommons.usm.maine.edu/megtf/1016/thumbnail.jp
Maine Gay Task Force Newsletter, Vol.3, No.04 (April 1976)
https://digitalcommons.usm.maine.edu/megtf/1012/thumbnail.jp
Maine Gay Task Force Newsletter, Vol.3, No.05 (May 1976)
https://digitalcommons.usm.maine.edu/megtf/1013/thumbnail.jp
Lymph node dissection in lung cancer surgery:a comparison between robot-assisted vs. video-assisted thoracoscopic approach
Background: TNM staging is the most important prognosticator for non-small cell lung cancer (NSCLC) patients. Staging has significant implications for the treatment modality for these patients. Lymph node dissection in robot-assisted thoracoscopic (RATS) surgery remains an area of ongoing evaluation. In this study, we aim to compare lymph node dissection in RATS and VATS approach for lung resection in NSCLC patients. Methods: We retrospectively compiled a database of 717 patients from July 31, 2015–July 7, 2022, who underwent either a wedge resection, segmentectomy or lobectomy. We analysed the database according to lymph node dissection. The database was divided into RATS (n = 375) and VATS (n = 342) procedures. Results: The mean number of lymph nodes harvested overall with RATS was 6.1 ± 1.5 nodes; with VATS approach, it was 5.53 ± 1.8 nodes. The mean number of N1 stations harvested was 2.66 ± 0.8 with RATS, 2.36 ± 0.9 with VATS. RATS approach showed statistically higher lymph node dissection rates compared to VATS (p = 0.002). Out of the 375 RATS procedures, 26 (6.4%) patients undergoing a RATS procedure were upstaged from N0/N1 staging to N2. N0/N1–N2 upstaging was reported in 28 of 342 (8.2%) patients undergoing a VATS procedure. The majority of upstaging was seen in N0–N2 disease: 19 of 375 (5%) for RATS and 23 of 342 (6.7%) for VATS. Conclusions: We conclude that in RATS procedures, there is a higher rate of lymph node dissection compared to VATS procedures. Upstaging was mostly seen in N0–N2 disease, this was observed at a higher rate with VATS procedures
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