807 research outputs found
Lunar penetrometer Patent
Development and characteristics of pentrometer for measuring physical properties of lunar surfac
Corporate Compliance With The FCPA
American corporations have learned to live reasonably with, if not actually love, the Foreign Corrupt Practices Act. Congress is currently being told that there are things that need correcting in the Act. Congress will eventually face these problems rather seriously so that a bill in some form will amend some of the things wrong with the Act. It is doubtful that any business person of good faith thinks there is anything wrong with the theses behind the Act. Business has learned, to its benefit, to live with the requirements of the Act
Molecular tendrils feeding star formation in the Eye of the Medusa - The Medusa merger in high resolution 12CO 2-1 maps
Studying molecular gas properties in merging galaxies gives us important
clues to the onset and evolution of interaction-triggered starbursts. NGC4194
is particularly interesting to study since its FIR-to-CO luminosity ratio
rivals that of ULIRGs,despite its lower luminosity compared to ULIRGs, which
indicates a high star formation efficiency that is relative to even most
spirals and ULIRGs.We study the molecular medium at an angular resolution of
0.65"x .52" through our observations of CO2-1 emission using the SMA. We
compare our CO2-1 maps with optical HST and high angular resolution radio
continuum images to study the relationship between molecular gas and other
components of the starburst region. The molecular gas is tracing the
complicated dust lane structure of NGC4194 with the brightest emission being
located in an off-nuclear ring-like structure with ~320pc radius, the Eye of
the Medusa. The bulk CO emission of the ring is found south of the kinematical
center of NGC4194. The northern tip of the ring is associated with the galaxy
nucleus, where the radio continuum has its peak. A prominent, secondary
emission maximum in the radio continuum is located inside the molecular ring.
This suggests that the morphology of the ring is partially influenced by
massive supernova explosions. From the combined evidence, we propose that the
Eye of the Medusa contains a shell of swept up material where we identify a
number of giant molecular associations. We propose that the Eye may be the site
of an efficient starburst of 5-7M_sun/yr, but it would still constitute only a
fraction of the 30-50M_sun/yr SFR of NGC4194. Furthermore, we find that ~50% of
the molecular mass of NGC4194 is found in extended filamentary-like structures
tracing the minor and major axis dust lanes. We suggest that molecular gas is
transported along these lanes providing the central starburst region with fuel.Comment: accepted for publication in A&A, 12 pages, 9 figure
Deep Space Network information system architecture study
The purpose of this article is to describe an architecture for the Deep Space Network (DSN) information system in the years 2000-2010 and to provide guidelines for its evolution during the 1990s. The study scope is defined to be from the front-end areas at the antennas to the end users (spacecraft teams, principal investigators, archival storage systems, and non-NASA partners). The architectural vision provides guidance for major DSN implementation efforts during the next decade. A strong motivation for the study is an expected dramatic improvement in information-systems technologies, such as the following: computer processing, automation technology (including knowledge-based systems), networking and data transport, software and hardware engineering, and human-interface technology. The proposed Ground Information System has the following major features: unified architecture from the front-end area to the end user; open-systems standards to achieve interoperability; DSN production of level 0 data; delivery of level 0 data from the Deep Space Communications Complex, if desired; dedicated telemetry processors for each receiver; security against unauthorized access and errors; and highly automated monitor and control
Recent advances in the enzymatic synthesis of sugar-nucleotides using nucleotidylyltransferases and glycosyltransferases
Sugar-nucleotides are imperative to carbohydrate metabolism and glycoconjugate biosynthesis. Enzymatic methods to access these key materials offer a powerful alternative to traditional chemical synthesis routes. Herein we review recent advances in the enzymatic pyrophosphorylation of glycosyl 1-phosphates for the provision of both native and modified sugar-nucleotides
ANALISIS KESULITAN SISWA DALAM MEMECAHKAN MASALAH MATEMATIKA PADA MATERI ARITMATIKA SOSIAL DI KELAS VII SMP NEGERI 2 BANDA ACEH TAHUN AJARAN 2013/2014
Banda Ace
Common elective orthopaedic procedures and their clinical effectiveness:umbrella review of level 1 evidence
OBJECTIVE: To determine the clinical effectiveness of common elective orthopaedic procedures compared with no treatment, placebo, or non-operative care and assess the impact on clinical guidelines. DESIGN: Umbrella review of meta-analyses of randomised controlled trials or other study designs in the absence of meta-analyses of randomised controlled trials. DATA SOURCES: Ten of the most common elective orthopaedic procedures—arthroscopic anterior cruciate ligament reconstruction, arthroscopic meniscal repair of the knee, arthroscopic partial meniscectomy of the knee, arthroscopic rotator cuff repair, arthroscopic subacromial decompression, carpal tunnel decompression, lumbar spine decompression, lumbar spine fusion, total hip replacement, and total knee replacement—were studied. Medline, Embase, Cochrane Library, and bibliographies were searched until September 2020. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Meta-analyses of randomised controlled trials (or in the absence of meta-analysis other study designs) that compared the clinical effectiveness of any of the 10 orthopaedic procedures with no treatment, placebo, or non-operative care. DATA EXTRACTION AND SYNTHESIS: Summary data were extracted by two independent investigators, and a consensus was reached with the involvement of a third. The methodological quality of each meta-analysis was assessed using the Assessment of Multiple Systematic Reviews instrument. The Jadad decision algorithm was used to ascertain which meta-analysis represented the best evidence. The National Institute for Health and Care Excellence Evidence search was used to check whether recommendations for each procedure reflected the body of evidence. MAIN OUTCOME MEASURES: Quality and quantity of evidence behind common elective orthopaedic interventions and comparisons with the strength of recommendations in relevant national clinical guidelines. RESULTS: Randomised controlled trial evidence supports the superiority of carpal tunnel decompression and total knee replacement over non-operative care. No randomised controlled trials specifically compared total hip replacement or meniscal repair with non-operative care. Trial evidence for the other six procedures showed no benefit over non-operative care. CONCLUSIONS: Although they may be effective overall or in certain subgroups, no strong, high quality evidence base shows that many commonly performed elective orthopaedic procedures are more effective than non-operative alternatives. Despite the lack of strong evidence, some of these procedures are still recommended by national guidelines in certain situations. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018115917
Deep observations of the Super-CLASS super-cluster at 325 MHz with the GMRT: the low-frequency source catalogue
We present the results of 325 MHz GMRT observations of a super-cluster field,
known to contain five Abell clusters at redshift . We achieve a
nominal sensitivity of Jy beam toward the phase centre. We
compile a catalogue of 3257 sources with flux densities in the range
within the entire square degree
field of view. Subsequently, we use available survey data at other frequencies
to derive the spectral index distribution for a sub-sample of these sources,
recovering two distinct populations -- a dominant population which exhibit
spectral index trends typical of steep-spectrum synchrotron emission, and a
smaller population of sources with typically flat or rising spectra. We
identify a number of sources with ultra-steep spectra or rising spectra for
further analysis, finding two candidate high-redshift radio galaxies and three
gigahertz-peaked-spectrum radio sources. Finally, we derive the
Euclidean-normalised differential source counts using the catalogue compiled in
this work, for sources with flux densities in excess of Jy. Our
differential source counts are consistent with both previous observations at
this frequency and models of the low-frequency source population. These
represent the deepest source counts yet derived at 325 MHz. Our source counts
exhibit the well-known flattening at mJy flux densities, consistent with an
emerging population of star-forming galaxies; we also find marginal evidence of
a downturn at flux densities below Jy, a feature so far only seen
at 1.4 GHz.Comment: 25 pages, 18 figures, 10 tables. Accepted for publication in MNRA
Revision for prosthetic joint infection following hip arthroplasty:Evidence from the National Joint Registry
Objectives We used the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man (NJR) to investigate the risk of revision due to prosthetic joint infection (PJI) for patients undergoing primary and revision hip arthroplasty, the changes in risk over time, and the overall burden created by PJI. Methods We analysed revision total hip arthroplasties (THAs) performed due to a diagnosis of PJI and the linked index procedures recorded in the NJR between 2003 and 2014. The cohort analysed consisted of 623 253 index primary hip arthroplasties, 63 222 index revision hip arthroplasties and 7585 revision THAs performed due to a diagnosis of PJI. The prevalence, cumulative incidence functions and the burden of PJI (total procedures) were calculated. Overall linear trends were investigated with log-linear regression. Results We demonstrated a prevalence of revision THA due to prosthetic joint infection of 0.4/100 procedures following primary and 1.6/100 procedures following revision hip arthroplasty. The prevalence of revision due to PJI in the three months following primary hip arthroplasty has risen 2.3-fold (95% confidence interval (CI) 1.3 to 4.1) between 2005 and 2013, and 3.0-fold (95% CI 1.1 to 8.5) following revision hip arthroplasty. Over 1000 procedures are performed annually as a consequence of hip PJI, an increase of 2.6-fold between 2005 and 2013. Conclusions Although the risk of revision due to PJI following hip arthroplasty is low, it is rising and, coupled with the established and further predicted increased incidence of both primary and revision hip arthroplasty, this represents a growing and substantial treatment burden. Cite this article: E. Lenguerrand, M. R. Whitehouse, A. D. Beswick, S. A. Jones, M. L. Porter, A. W. Blom. Revision for prosthetic joint infection following hip arthroplasty: Evidence from the National Joint Registry. Bone Joint Res 2017;6:391–398. DOI: 10.1302/2046-3758.66.BJR-2017-0003.R1. </jats:sec
8.4GHz VLBI observations of SN2004et in NGC6946
We report on 8.4GHz Very Long Baseline Interferometry (VLBI) observations of
the type II-P supernova SN2004et in the spiral galaxy NGC 6946, made on 20
February 2005 (151 days after explosion). The Very Large Array (VLA) flux
density was 1.230.07 mJy, corresponding to an isotropic luminosity at
8.4GHz of (4.450.3) erg s Hz and a brightness
temperature of (1.30.3) K. We also provide an improved
source position, accurate to about 0.5 mas in each coordinate. The VLBI image
shows a clear asymmetry. From model fitting of the size of the radio emission,
we estimate a minimum expansion velocity of 15,7002,000 km s. This
velocity is more than twice the expected mean expansion velocity estimated from
a synchrotron self-absorbed emission model, thus suggesting that synchrotron
self-absorption is not relevant for this supernova. With the benefit of an
optical spectrum obtained 12 days after explosion, we favor an emission model
which consists of two hot spots on an underlying expanding shell of width
comparable to that of SN 1993J.Comment: Accepted for publication in A&A (22/05/07
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