756 research outputs found
The Monument Project (Si Monumentum Reqiuis Circumspice) Leonardo article
This paper describes the concepts, ideas, background and operations of The Monument Project (Si Monumentum Requiris Circumspice), a digital video installation that produces a continuous stream of weather-responsive panoramic images from the top of the Monument in the City of London. The work, which was commissioned by Julian Harrap Architects, was part of a £4.5 million refurbishment of the 17th-century landmark, designed by Sir Christopher Wren and Dr. Robert Hooke to commemorate the Great Fire of London in 1666
A Phase III Randomized Trial of Gemcitabine–Oxaliplatin versus Carboplatin–Paclitaxel as First-Line Therapy in Patients with Advanced Non-small Cell Lung Cancer
Purpose:This phase III study compared the efficacy and tolerability of gemcitabine and oxaliplatin (GEMOX) with paclitaxel and carboplatin (PCb) in chemotherapy-naive patients with stage IIIB/IV non-small cell lung cancer.Patients and Methods:Patients aged 18 years or older were randomized to PCb (paclitaxel 225 mg/m2 followed by carboplatin area under the curve = 6 on day 1 every 3 weeks) or GEMOX (gemcitabine 1,000 mg/m2 on days 1 and 8 followed by oxaliplatin 130 mg/m2 on day 1 every 3 weeks) for up to six cycles. The primary end point was progression-free survival (PFS), with tumor response rate, overall survival (OS), and quality of life as secondary end points.Results:The study was terminated after 383 patients had been randomized (371 received treatment) as the incidence of adverse events had exceeded the protocol-specified safety threshold (≥20% in either arm). No formal statistical comparisons were conducted. Median PFS was 4.44 months and 4.67 months in the GEMOX and PCb groups, respectively. Objective response rates (complete or partial) were 15.2% and 22.4% in the GEMOX and PCb arms, respectively. Median OS was 9.90 months (GEMOX) and 9.24 months (PCb); post hoc analyses showed median OS in patients aged 70 years or older to be similar to those younger than 70 years. PFS was similar in both groups of patients with adenocarcinoma histology, although OS favored the GEMOX group. Quality of life was improved from baseline in both groups. Toxicity profiles were comparable between the groups.Conclusion:PFS, OS, and objective response rates with GEMOX were similar to PCb. Nevertheless, toxicities limit the adoption of this regimen for routine use in advanced non-small cell lung cancer
Sea Louse Infection of Juvenile Sockeye Salmon in Relation to Marine Salmon Farms on Canada's West Coast
BACKGROUND: Pathogens are growing threats to wildlife. The rapid growth of marine salmon farms over the past two decades has increased host abundance for pathogenic sea lice in coastal waters, and wild juvenile salmon swimming past farms are frequently infected with lice. Here we report the first investigation of the potential role of salmon farms in transmitting sea lice to juvenile sockeye salmon (Oncorhynchus nerka). METHODOLOGY/PRINCIPAL FINDINGS: We used genetic analyses to determine the origin of sockeye from Canada's two most important salmon rivers, the Fraser and Skeena; Fraser sockeye migrate through a region with salmon farms, and Skeena sockeye do not. We compared lice levels between Fraser and Skeena juvenile sockeye, and within the salmon farm region we compared lice levels on wild fish either before or after migration past farms. We matched the latter data on wild juveniles with sea lice data concurrently gathered on farms. Fraser River sockeye migrating through a region with salmon farms hosted an order of magnitude more sea lice than Skeena River populations, where there are no farms. Lice abundances on juvenile sockeye in the salmon farm region were substantially higher downstream of farms than upstream of farms for the two common species of lice: Caligus clemensi and Lepeophtheirus salmonis, and changes in their proportions between two years matched changes on the fish farms. Mixed-effects models show that position relative to salmon farms best explained C. clemensi abundance on sockeye, while migration year combined with position relative to salmon farms and temperature was one of two top models to explain L. salmonis abundance. CONCLUSIONS/SIGNIFICANCE: This is the first study to demonstrate a potential role of salmon farms in sea lice transmission to juvenile sockeye salmon during their critical early marine migration. Moreover, it demonstrates a major migration corridor past farms for sockeye that originated in the Fraser River, a complex of populations that are the subject of conservation concern
Quantum wires from coupled InAs/GaAs strained quantum dots
The electronic structure of an infinite 1D array of vertically coupled
InAs/GaAs strained quantum dots is calculated using an eight-band
strain-dependent k-dot-p Hamiltonian. The coupled dots form a unique quantum
wire structure in which the miniband widths and effective masses are controlled
by the distance between the islands, d. The miniband structure is calculated as
a function of d, and it is shown that for d>4 nm the miniband is narrower than
the optical phonon energy, while the gap between the first and second minibands
is greater than the optical phonon energy. This leads to decreased optical
phonon scattering, providing improved quantum wire behavior at high
temperatures. These miniband properties are also ideal for Bloch oscillation.Comment: 5 pages revtex, epsf, 8 postscript figure
The nature of the torus in the heavily obscured AGN Markarian 3: an X-ray study
In this paper we report the results of an X-ray monitoring campaign on the
heavily obscured Seyfert galaxy Markarian 3 carried out between the fall of
2014 and the spring of 2015 with NuSTAR, Suzaku and XMM-Newton. The hard X-ray
spectrum of Markarian 3 is variable on all the time scales probed by our
campaign, down to a few days. The observed continuum variability is due to an
intrinsically variable primary continuum seen in transmission through a large,
but still Compton-thin column density (N_H~0.8-1.110 cm).
If arranged in a spherical-toroidal geometry, the Compton scattering matter has
an opening angle ~66 degrees and is seen at a grazing angle through its upper
rim (inclination angle ~70 degrees). We report a possible occultation event
during the 2014 campaign. If the torus is constituted by a system of clouds
sharing the same column density, this event allows us to constrain their number
(175) and individual column density, [~(4.91.5)10
cm]. The comparison of IR and X-ray spectroscopic results with
state-of-the art "torus" models suggests that at least two thirds of the X-ray
obscuring gas volume might be located within the dust sublimation radius. We
report also the discovery of an ionized absorber, characterised by variable
resonant absorption lines due to He- and H-like iron. This discovery lends
support to the idea that moderate column density absorbers could be due to
clouds evaporated at the outer surface of the torus, possibly accelerated by
the radiation pressure due to the central AGN emission leaking through the
patchy absorber.Comment: Accepted for publication in MNRAS, 17 pages, 11 figures, 5 table
Use of Rollover Protective Structures -- Iowa, Kentucky, New York, and Ohio, 1992-1997
Agriculture has one of the highest occupational fatality rates of all industries in the United States (1). Tractors and other types of agricultural equipment account for a large proportion of these fatalities, and farm-tractor rollovers account for approximately 130 work-related deaths each year in the United States (2). Although rollover protective structures (ROPS) are effective in protecting tractor operators from fatal injuries during rollovers (3-5), most tractors in the United States are not equipped with ROPS (4-7). Beginning in 1985, tractor manufacturers in the United Sates agreed to sell only tractors with ROPS; however, many older tractors without ROPS remain in use. To determine the prevalence of the use of ROPS, beginning in 1992, the Farm Family Health and Hazard Surveillance (FFHHS) program * collected state-based data on tractor age and use of ROPS from selected states. As of August 1997, four states had completed collection and analysis of data on farm tractors. This report summarizes the results of that survey, which indicates that 80%-90% of tractors in use in the four states were manufactured before 1985 and that less than 40% are equipped with ROPS
Enteral lactoferrin supplementation for very preterm infants: a randomised placebo-controlled trial
Background
Infections acquired in hospital are an important cause of morbidity and mortality in very preterm infants. Several small trials have suggested that supplementing the enteral diet of very preterm infants with lactoferrin, an antimicrobial protein processed from cow's milk, prevents infections and associated complications. The aim of this large randomised controlled trial was to collect data to enhance the validity and applicability of the evidence from previous trials to inform practice.
Methods
In this randomised placebo-controlled trial, we recruited very preterm infants born before 32 weeks' gestation in 37 UK hospitals and younger than 72 h at randomisation. Exclusion criteria were presence of a severe congenital anomaly, anticipated enteral fasting for longer than 14 days, or no realistic prospect of survival. Eligible infants were randomly assigned (1:1) to receive either enteral bovine lactoferrin (150 mg/kg per day; maximum 300 mg/day; lactoferrin group) or sucrose (same dose; control group) once daily until 34 weeks' postmenstrual age. Web-based randomisation minimised for recruitment site, gestation (completed weeks), sex, and single versus multifetal pregnancy. Parents, caregivers, and outcome assessors were unaware of group assignment. The primary outcome was microbiologically confirmed or clinically suspected late-onset infection (occurring >72 h after birth), which was assessed in all participants for whom primary outcome data was available by calculating the relative risk ratio with 95% CI between the two groups. The trial is registered with the International Standard Randomised Controlled Trial Number 88261002.
Findings
We recruited 2203 participants between May 7, 2014, and Sept 28, 2017, of whom 1099 were assigned to the lactoferrin group and 1104 to the control group. Four infants had consent withdrawn or unconfirmed, leaving 1098 infants in the lactoferrin group and 1101 in the sucrose group. Primary outcome data for 2182 infants (1093 [99·5%] of 1098 in the lactoferrin group and 1089 [99·0] of 1101 in the control group) were available for inclusion in the modified intention-to-treat analyses. 316 (29%) of 1093 infants in the intervention group acquired a late-onset infection versus 334 (31%) of 1089 in the control group. The risk ratio adjusted for minimisation factors was 0·95 (95% CI 0·86–1·04; p=0·233). During the trial there were 16 serious adverse events for infants in the lactoferrin group and 10 for infants in the control group. Two events in the lactoferrin group (one case of blood in stool and one death after intestinal perforation) were assessed as being possibly related to the trial intervention.
Interpretation
Enteral supplementation with bovine lactoferrin does not reduce the risk of late-onset infection in very preterm infants. These data do not support its routine use to prevent late-onset infection and associated morbidity or mortality in very preterm infants.
Funding
UK National Institute for Health Research Health Technology Assessment programme (10/57/49)
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Enteral lactoferrin supplementation for very preterm infants: a randomised placebo-controlled trial
Background
Infections acquired in hospital are an important cause of morbidity and mortality in very preterm infants. Several small trials have suggested that supplementing the enteral diet of very preterm infants with lactoferrin, an antimicrobial protein processed from cow's milk, prevents infections and associated complications. The aim of this large randomised controlled trial was to collect data to enhance the validity and applicability of the evidence from previous trials to inform practice.
Methods
In this randomised placebo-controlled trial, we recruited very preterm infants born before 32 weeks' gestation in 37 UK hospitals and younger than 72 h at randomisation. Exclusion criteria were presence of a severe congenital anomaly, anticipated enteral fasting for longer than 14 days, or no realistic prospect of survival. Eligible infants were randomly assigned (1:1) to receive either enteral bovine lactoferrin (150 mg/kg per day; maximum 300 mg/day; lactoferrin group) or sucrose (same dose; control group) once daily until 34 weeks' postmenstrual age. Web-based randomisation minimised for recruitment site, gestation (completed weeks), sex, and single versus multifetal pregnancy. Parents, caregivers, and outcome assessors were unaware of group assignment. The primary outcome was microbiologically confirmed or clinically suspected late-onset infection (occurring >72 h after birth), which was assessed in all participants for whom primary outcome data was available by calculating the relative risk ratio with 95% CI between the two groups. The trial is registered with the International Standard Randomised Controlled Trial Number 88261002.
Findings
We recruited 2203 participants between May 7, 2014, and Sept 28, 2017, of whom 1099 were assigned to the lactoferrin group and 1104 to the control group. Four infants had consent withdrawn or unconfirmed, leaving 1098 infants in the lactoferrin group and 1101 in the sucrose group. Primary outcome data for 2182 infants (1093 [99·5%] of 1098 in the lactoferrin group and 1089 [99·0] of 1101 in the control group) were available for inclusion in the modified intention-to-treat analyses. 316 (29%) of 1093 infants in the intervention group acquired a late-onset infection versus 334 (31%) of 1089 in the control group. The risk ratio adjusted for minimisation factors was 0·95 (95% CI 0·86–1·04; p=0·233). During the trial there were 16 serious adverse events for infants in the lactoferrin group and 10 for infants in the control group. Two events in the lactoferrin group (one case of blood in stool and one death after intestinal perforation) were assessed as being possibly related to the trial intervention.
Interpretation
Enteral supplementation with bovine lactoferrin does not reduce the risk of late-onset infection in very preterm infants. These data do not support its routine use to prevent late-onset infection and associated morbidity or mortality in very preterm infants.
Funding
UK National Institute for Health Research Health Technology Assessment programme (10/57/49)
Vertical structure of dissipation in the nearshore
Author Posting. © American Meteorological Society, 2007. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 37 (2007): 1764-1777, doi:10.1175/jpo3098.1.The vertical structure of the dissipation of turbulence kinetic energy was observed in the nearshore region (3.2-m mean water depth) with a tripod of three acoustic Doppler current meters off a sandy ocean beach. Surface and bottom boundary layer dissipation scaling concepts overlap in this region. No depth-limited wave breaking occurred at the tripod, but wind-induced whitecapping wave breaking did occur. Dissipation is maximum near the surface and minimum at middepth, with a secondary maximum near the bed. The observed dissipation does not follow a surfzone scaling, nor does it follow a “log layer” surface or bottom boundary layer scaling. At the upper two current meters, dissipation follows a modified deep-water breaking-wave scaling. Vertical shear in the mean currents is negligible and shear production magnitude is much less than dissipation, implying that the vertical diffusion of turbulence is important. The increased near-bed secondary dissipation maximum results from a decrease in the turbulent length scale.Funding was provided by NSF
and ONR
The Suppressor of AAC2 Lethality SAL1 Modulates Sensitivity of Heterologously Expressed Artemia ADP/ATP Carrier to Bongkrekate in Yeast
The ADP/ATP carrier protein (AAC) expressed in Artemia franciscana is refractory to bongkrekate. We generated two strains of Saccharomyces cerevisiae where AAC1 and AAC3 were inactivated and the AAC2 isoform was replaced with Artemia AAC containing a hemagglutinin tag (ArAAC-HA). In one of the strains the suppressor of ΔAAC2 lethality, SAL1, was also inactivated but a plasmid coding for yeast AAC2 was included, because the ArAACΔsal1Δ strain was lethal. In both strains ArAAC-HA was expressed and correctly localized to the mitochondria. Peptide sequencing of ArAAC expressed in Artemia and that expressed in the modified yeasts revealed identical amino acid sequences. The isolated mitochondria from both modified strains developed 85% of the membrane potential attained by mitochondria of control strains, and addition of ADP yielded bongkrekate-sensitive depolarizations implying acquired sensitivity of ArAAC-mediated adenine nucleotide exchange to this poison, independent from SAL1. However, growth of ArAAC-expressing yeasts in glycerol-containing media was arrested by bongkrekate only in the presence of SAL1. We conclude that the mitochondrial environment of yeasts relying on respiratory growth conferred sensitivity of ArAAC to bongkrekate in a SAL1-dependent manner. © 2013 Wysocka-Kapcinska et al
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