2,224 research outputs found
Optimal Time Allocation between Idle and Active Time
Idle time is an essential and valuable factor in the production of any service. While idle time is necessary and helpful for efficient and effective utilization of time, it also has a negative effect that managers try to minimize. This paper illustrates either analytically or numerically the different effects of idle time on total net revenue. It first presents the case in which idle time is determined arbitrarily, and then shows idle time that has no direct negative effect on total revenue but a positive effect on the efficient use of active time
Assessing the applicability of transcript conformation polymorphism for differentiation among «Prunus nocrotic ringspot virus» isolates
The applicability of single and double-stranded transcript conformation polymorphism (TCP) for differentiation
among Prunus necrotic ringspot virus (PNRSV) isolates was evaluated and compared with other molecular
differentiation procedures. Single-stranded TCP was found to be suitable to differentiate closely related virus isolates.
However, due to its high variability, it was not suitable for grouping virus isolates. Double-stranded TCP, on the
other hand, enabled the division of virus isolates into major groups. Restriction fragment length polymorphism
(RFLP) of the PCR products confirmed the grouping of the virus isolates but this technique was limited in its ability
to detect a wide range of nucleotide modifications. Nucleotide sequence analysis was essential for the detection of
strain-specific sequences but did not clearly identify most other minor modifications that are necessary for virus
classification. The combination of all methods is therefore sometimes required for complete analysis
Studying the atmosphere of the exoplanet HAT-P-7b via secondary eclipse measurements with EPOXI, Spitzer and Kepler
The highly irradiated transiting exoplanet, HAT-P-7b, currently provides one
of the best opportunities for studying planetary emission in the optical and
infrared wavelengths. We observe six near-consecutive secondary eclipses of
HAT-P-7b at optical wavelengths with the EPOXI spacecraft. We place an upper
limit on the relative eclipse depth of 0.055% (95% confidence). We also analyze
Spitzer observations of the same target in the infrared, obtaining secondary
eclipse depths of 0.098+/-0.017%, 0.159+/-0.022%, 0.245+/-0.031% and
0.225+/-0.052% in the 3.6, 4.5, 5.8 and 8.0 micron IRAC bands respectively. We
combine these measurements with the recently published Kepler secondary eclipse
measurement, and generate atmospheric models for the day-side of the planet
that are consistent with both the optical and infrared measurements. The data
are best fit by models with a temperature inversion, as expected from the high
incident flux. The models predict a low optical albedo of ~< 0.13, with
subsolar abundances of Na, K, TiO and VO. We also find that the best fitting
models predict that 10% of the absorbed stellar flux is redistributed to the
night side of the planet, which is qualitatively consistent with the
inefficient day-night redistribution apparent in the Kepler phase curve. Models
without thermal inversions fit the data only at the 1.25 sigma level, and also
require an overabundance of methane, which is not expected in the very hot
atmosphere of HAT-P-7b. We also analyze the eight transits of HAT-P-7b present
in the EPOXI dataset and improve the constraints on the system parameters,
finding a period of P = 2.2047308+/-0.0000025 days, a stellar radius of R* =
1.824+/-0.089Rsun, a planetary radius of Rp = 1.342+/-0.068RJup and an
inclination of i = 85.7+3.5-2.2 deg.Comment: 21 pages, 8 figures, accepted by the Astrophysical Journa
A Spitzer Transmission Spectrum for the Exoplanet GJ 436b, Evidence for Stellar Variability, and Constraints on Dayside Flux Variations
In this paper we describe a uniform analysis of eight transits and eleven
secondary eclipses of the extrasolar planet GJ 436b obtained in the 3.6, 4.5,
and 8.0 micron bands using the IRAC instrument on the Spitzer Space Telescope
between UT 2007 June 29 and UT 2009 Feb 4. We find that the best-fit transit
depths for visits in the same bandpass can vary by as much as 8% of the total
(4.7 sigma significance) from one epoch to the next. Although we cannot
entirely rule out residual detector effects or a time-varying, high-altitude
cloud layer in the planet's atmosphere as the cause of these variations, we
consider the occultation of active regions on the star in a subset of the
transit observations to be the most likely explanation. We reconcile the
presence of magnetically active regions with the lack of significant visible or
infrared flux variations from the star by proposing that the star's spin axis
is tilted with respect to our line of sight, and that the planet's orbit is
therefore likely to be misaligned. These observations serve to illustrate the
challenges associated with transmission spectroscopy of planets orbiting
late-type stars; we expect that other systems, such as GJ 1214, may display
comparably variable transit depths. Our measured 8 micron secondary eclipse
depths are consistent with a constant value, and we place a 1 sigma upper limit
of 17% on changes in the planet's dayside flux in this band. Averaging over the
eleven visits gives us an improved estimate of 0.0452% +/- 0.0027% for the
secondary eclipse depth. We combine timing information from our observations
with previously published data to produce a refined orbital ephemeris, and
determine that the best-fit transit and eclipse times are consistent with a
constant orbital period. [ABRIDGED]Comment: 26 pages, 18 figures, 7 tables in emulateapj format. Accepted for
publication in Ap
Continuous subcutaneous foslevodopa/foscarbidopa infusion for the treatment of motor fluctuations in Parkinson's disease:Considerations for initiation and maintenance
Background:As Parkinson's disease (PD) advances, management is challenged by an increasingly variable and inconsistent response to oral dopaminergic therapy, requiring special considerations by the provider. Continuous 24 h/day subcutaneous infusion of foslevodopa/foscarbidopa (LDp/CDp) provides steady dopaminergic stimulation that can reduce symptom fluctuation. Objective: Our aim is to review the initiation, optimization, and maintenance of LDp/CDp therapy, identify possible challenges, and share potential mitigations.Methods: Review available LDp/CDp clinical trial data for practical considerations regarding the management of patients during LDp/CDp therapy initiation, optimization, and maintenance based on investigator clinical trial experience. Results: LDp/CDp initiation, optimization, and maintenance can be done without hospitalization in the clinic setting. Continuous 24 h/day LDp/CDp infusion can offer more precise symptom control than oral medications, showing improvements in motor fluctuations during both daytime and nighttime hours. Challenges include infusion-site adverse events for which early detection and prompt management may be required, as well as systemic adverse events (eg, hallucinations) that may require adjustment of the infusion rate or other interventions. A learning curve should be anticipated with initiation of therapy, and expectation setting with patients and care partners is key to successful initiation and maintenance of therapy. Conclusion: Continuous subcutaneous infusion of LDp/CDp represents a promising therapeutic option for individuals with PD. Individualized dose optimization during both daytime and nighttime hours, coupled with patient education, and early recognition of certain adverse events (plus their appropriate management) are required for the success of this minimally invasive and highly efficacious therapy.</p
TOWARD THE MINIMUM INNER EDGE DISTANCE OF THE HABITABLE ZONE
We explore the minimum distance from a host star where an exoplanet could potentially be habitable in order not to discard close-in rocky exoplanets for follow-up observations. We find that the inner edge of the Habitable Zone for hot desert worlds can be as close as 0.38 AU around a solar-like star, if the greenhouse effect is reduced (~1% relative humidity) and the surface albedo is increased. We consider a wide range of atmospheric and planetary parameters such as the mixing ratios of greenhouse gases (water vapor and CO[subscript 2]), surface albedo, pressure, and gravity. Intermediate surface pressure (~1-10 bars) is necessary to limit water loss and to simultaneously sustain an active water cycle. We additionally find that the water loss timescale is influenced by the atmospheric CO[subscript 2] level, because it indirectly influences the stratospheric water mixing ratio. If the CO[subscript 2] mixing ratio of dry planets at the inner edge is smaller than 10[superscript –4], the water loss timescale is ~1 billion years, which is considered here too short for life to evolve. We also show that the expected transmission spectra of hot desert worlds are similar to an Earth-like planet. Therefore, an instrument designed to identify biosignature gases in an Earth-like atmosphere can also identify similarly abundant gases in the atmospheres of dry planets. Our inner edge limit is closer to the host star than previous estimates. As a consequence, the occurrence rate of potentially habitable planets is larger than previously thought
Oncological outcome and patient satisfaction with skin-sparing mastectomy and immediate breast reconstruction: a prospective observational study
<p>Abstract</p> <p>Background</p> <p>The management of early breast cancer (BC) with skin-sparing mastectomy (SSM) and immediate breast reconstruction (IBR) is not based on level-1 evidence. In this study, the oncological outcome, post-operative morbidity and patients' satisfaction with SSM and IBR using the latissimus dorsi (LD) myocutaneous flap and/or breast prosthesis is evaluated.</p> <p>Methods</p> <p>137 SSMs with IBR (10 bilateral) were undertaken in 127 consecutive women, using the LD flap plus implant (n = 85), LD flap alone (n = 1) or implant alone (n = 51), for early BC (n = 130) or prophylaxis (n = 7). Nipple reconstruction was performed in 69 patients, using the trefoil local flap technique (n = 61), nipple sharing (n = 6), skin graft (n = 1) and Monocryl mesh (n = 1). Thirty patients underwent contra-lateral procedures to enhance symmetry, including 19 augmentations and 11 mastopexy/reduction mammoplasties. A linear visual analogue scale was used to assess patient satisfaction with surgical outcome, ranging from 0 (not satisfied) to 10 (most satisfied).</p> <p>Results</p> <p>After a median follow-up of 36 months (range = 6-101 months) there were no local recurrences. Overall breast cancer specific survival was 99.2%, 8 patients developed distant disease and 1 died of metastatic BC. There were no cases of partial or total LD flap loss. Morbidities included infection, requiring implant removal in 2 patients and 1 patient developed marginal ischaemia of the skin envelope. Chemotherapy was delayed in 1 patient due to infection. Significant capsule formation, requiring capsulotomy, was observed in 85% of patients who had either post-mastectomy radiotherapy (PMR) or prior radiotherapy (RT) compared with 13% for those who had not received RT. The outcome questionnaire was completed by 82 (64.6%) of 127 patients with a median satisfaction score of 9 (range = 5-10).</p> <p>Conclusion</p> <p>SSM with IBR is associated with low morbidity, high levels of patient satisfaction and is oncologically safe for T(is), T1 and T2 tumours without extensive skin involvement.</p
D5.3 Resilience assessment of current farming systems across the European Union
For improving sustainability and resilience of EU farming system, the current state needs to be
assessed, before being able to move on to future scenarios. Assessing sustainability and resilience
of farming systems is a multi-faceted research challenge in terms of the scientific domains and
scales of integration (farm, household, farming system level) that need to be covered. Hence, in
SURE-Farm, multiple approaches are used to evaluate current sustainability and resilience and its
underlying structures and drivers. To maintain consistency across the different approaches, all
approaches are connected to a resilience framework which was developed for the unique
purposes of SURE-Farm. The resilience framework follows five steps: 1) the farming system
(resilience of what?), 2) challenges (resilience to what?), 3) functions (resilience for what
purpose?), 4) resilience capacities, 5) resilience attributes (what enhances resilience?). The
framework was operationalized in 11 case studies across the EU.
Applied approaches differ in disciplinary orientation and the farming system process they focus
on. Three approaches focus on risk management: 1) a farm survey with a main focus on risk
management and risk management strategies, 2) interviews on farmers’ learning capacity and
networks of influence, and 3) Focus Groups on risk management. Two approaches address farm
demographics: 4) interviews on farm demographics, and 5) AgriPoliS Focus Group workshops on
structural change of farming systems from a (farm) demographics perspective. One approach
applied so far addresses governance: 6) the Resilience Assessment Tool that evaluates how
policies and legislation support resilience of farming systems. Two methods address agricultural
production and delivery of public and private goods: 7) the Framework of Participatory Impact
Assessment for sustainable and resilient farming systems (FoPIA-SURE-Farm), aiming to integrate
multiple perspectives at farming system level, and 8) the Ecosystem Services assessment that
evaluates the delivery of public and private goods. In a few case studies, additional methods were
applied. Specifically, in the Italian case study, additional statistical approaches were used to
increase the support for risk management options (Appendix A and Appendix B).
Results of the different methods were compared and synthesized per step of the resilience
framework. Synthesized results were used to determine the position of the farming system in the
adaptive cycle, i.e. in the exploitation, conservation, release, or reorganization phase. Dependent
on the current phase of the farming system, strategies for improving sustainability and resilience
were developed.
Results were synthesized around the three aspects characterizing the SURE-Farm framework, i.e.
(i) it studies resilience at the farming system level, (ii) considers three resilience capacities, and
(iii) assesses resilience in the context of the (changing) functions of the system.
(i) Many actors are part of the farming system. However, resilience-enhancing strategies are
mostly defined at the farm level. In each farming system multiple actors are considered to
be part of the system, such as consultants, neighbors, local selling networks and nature
organizations. The number of different farming system actors beyond the focal farmers
varies between 4 (in French beef and Italian hazelnut systems) and 14 (large-scale arable
systems in the UK). These large numbers of actors illustrate the relevance of looking at
farming system level rather than at farm level. It also suggests that discussions about
resilience and future strategies need to embrace all of these actors.
(ii) At system level there is a low perceived capacity to transform. Yet, most systems appear to
be at the start of a period in which (incremental) transformation is required. At system level,
the capacity to transform is perceived to be relatively low, except in the Romanian mixed
farming system. The latter may reflect a combination of ample room to grow and a relatively
stable environment (especially when compared to the past 30 to 50 years). The relatively
low capacity to transform in the majority of systems is not in line with the suggestion that
most systems are at the start of (incremental) transformation, or, at least, reached a
situation in which they can no longer grow. Further growth is only deemed possible in the
Belgium dairy, Italian hazelnut, Polish fruit and Romanian mixed farming systems.
(iii) System functions score well with regard to the delivery of high-quality and safe food but face
problems with quality of rural life and protecting biodiversity. Resilience capacities can only
be understood in the context of the functions to be delivered by a farming system. We find
that across all systems required functions are a mix of private and public goods. With regard
to the capacity to deliver private goods, all systems perform well with respect to high-quality
and safe food. Viability of farm income is regarded moderate or low in the livestock systems
in Belgium (dairy), France (beef) and Sweden (broilers), and the fruit farming system in
Poland. Across all functions, attention is especially needed for the delivery of public goods.
More specifically the quality of rural life and infrastructure are frequently classified as being
important, but currently performing bad. Despite the concerns about the delivery of public
goods, many future strategies still focus on improving the delivery of private goods.
Suggestions in the area of public goods include among others the implementation of
conservation farming in the UK arable system, improved water management in the Italian
hazelnut system, and introduction of technologies which reduce the use of herbicides in
Polish fruit systems. It is questionable whether these are sufficient to address the need to
improve the maintenance of natural resources, biodiversity and attractiveness of rural
areas. With regard to the changing of functions over time, we did not find evidence for this
in our farming systems
Plant trait and vegetation data along a 1314 m elevation gradient with fire history in Puna grasslands, Perú
Alpine grassland vegetation supports globally important biodiversity and ecosystems that are increasingly threatened by climate warming and other environmental changes. Trait-based approaches can support understanding of vegetation responses to global change drivers and consequences for ecosystem functioning. In six sites along a 1314 m elevational gradient in Puna grasslands in the Peruvian Andes, we collected datasets on vascular plant composition, plant functional traits, biomass, ecosystem fluxes, and climate data over three years. The data were collected in the wet and dry season and from plots with different fire histories. We selected traits associated with plant resource use, growth, and life history strategies (leaf area, leaf dry/wet mass, leaf thickness, specific leaf area, leaf dry matter content, leaf C, N, P content, C and N isotopes). The trait dataset contains 3,665 plant records from 145 taxa, 54,036 trait measurements (increasing the trait data coverage of the regional flora by 420%) covering 14 traits and 121 plant taxa (ca. 40% of which have no previous publicly available trait data) across 33 families
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