COSP Bodas-Salcedo, A.; Webb, M. J.; Bony, S. ...
Bulletin of the American Meteorological Society,
08/2011, Letnik:
92, Številka:
8
Journal Article
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Errors in the simulation of clouds in general circulation models (GCMs) remain a long-standing issue in climate projections, as discussed in the Intergovernmental Panel on Climate Change (IPCC) ...Fourth Assessment Report. This highlights the need for developing new analysis techniques to improve our knowledge of the physical processes at the root of these errors. The Cloud Feedback Model Intercomparison Project (CFMIP) pursues this objective, and under that framework the CFMIP Observation Simulator Package (COSP) has been developed. COSP is a flexible software tool that enables the simulation of several satellite-borne active and passive sensor observations from model variables. The flexibility of COSP and a common interface for all sensors facilitates its use in any type of numerical model, from high-resolution cloud-resolving models to the coarser-resolution GCMs assessed by the IPCC, and the scales in between used in weather forecast and regional models. The diversity of model parameterization techniques makes the comparison between model and observations difficult, as some parameterized variables (e.g., cloud fraction) do not have the same meaning in all models. The approach followed in COSP permits models to be evaluated against observations and compared against each other in a more consistent manner. This permits a more detailed diagnosis of the physical processes that govern the behavior of clouds and precipitation in numerical models. The World Climate Research Programme (WCRP) Working Group on Coupled Modelling has recommended the use of COSP in a subset of climate experiments that will be assessed by the next IPCC report. In this article we describe COSP, present some results from its application to numerical models, and discuss future work that will expand its capabilities.
The efficient use of resources is a key factor to minimize the cost while meeting time deadlines and quality requirements; this is especially important in construction projects where field operations ...make fluctuations of resources unproductive and costly. Resource Leveling Problems (RLP) aim to sequence the construction activities that maximize the resource consumption efficiency over time, minimizing the variability. Exact algorithms for the RLP have been proposed throughout the years to offer optimal solutions; however, these problems require a vast computational capability (“combinatorial explosion”) that makes them unpractical. Therefore, alternative heuristic and metaheuristic algorithms have been suggested in the literature to find local optimal solutions, using different libraries to benchmark optimal values; for example, the Project Scheduling Problem LIBrary for minimal lags is still open to be solved to optimality for RLP. To partially fill this gap, the authors propose a Parallel Branch and Bound algorithm for the RLP with minimal lags to solve the RLP with an acceptable computational effort. This way, this research contributes to the body of knowledge of construction project scheduling providing the optimums of 50 problems for the RLP with minimal lags for the first time, allowing future contributors to benchmark their heuristics methods against exact results by obtaining the distance of their solution to the optimal values. Furthermore, for practitioners, the time required to solve this kind of problem is reasonable and practical, considering that unbalanced resources can risk the goals of the construction project.
DFT with long-range corrections and ONIOM along with a polarizable-continuum model were used to analyze zeolites BEA, FAU, MFI, and BEC substituted with Sn and Ti. The preferential substitution sites ...for Ti and Sn in the different frameworks are reported. The Lewis acidities were measured through the NH3 binding energies and through the charge transfer of NH3 upon adsorption. The deprotonation energies of the open sites, which are proportional to the Brønsted acidities, and the hydrolysis energies are also reported. We also present the properties of BEA with a single and a double Sn-substitution to compare the active sites obtained with two methods commonly employed for the synthesis of Sn–BEA. Among the zeolites analyzed in this study, Sn–BEA with a double Sn-substitution has the highest Lewis acidity. The formation of open sites through the hydrolysis of Sn–BEA, Sn–FAU, and Ti–FAU is energetically favorable, but it is not favorable in MFI or Ti–BEA. On the basis of the deprotonation energies, the open sites of Sn–BEA have a strong Brønsted acidity, comparable to Al–BEA or Al–MFI. We also demonstrate that the VDW forces in the binding energies of NH3 on MFI are more significant than in the other zeolite frameworks and that these forces decrease with increasing pore size.
We investigate the structure and formation of charmed meson–nucleus systems, with the aim of understanding the charmed meson–nucleon interactions and the properties of the charmed mesons in the ...nuclear medium. The D¯ mesic nuclei are of special interest, since they have tiny decay widths due to the absence of strong decays for the D¯N pair. Employing an effective model for the D¯N and DN interactions and solving the Klein–Gordon equation for D¯ and D in finite nuclei, we find that the D−–11B system has 1s and 2p mesic nuclear states and that the D0–11B system binds in a 1s state. In view of the forthcoming experiments by the PANDA and CBM Collaborations at the future FAIR facility and the J-PARC upgrade, we calculate the formation spectra of the D−–11B and D0–11B mesic nuclei for an antiproton beam on a 12C target. Our results suggest that it is possible to observe the 2pD− mesic nuclear state with an appropriate experimental setup.
SARS-Cov2 s, caused a high mortality in patients with some degree of immunosuppression, like those that receive a hematopoietic progenitor transplant. Since December 2020, several vaccines have been ...developed having been key in decreasing complications and mortality in this group of patients. Different articles have described the presence of thrombopenia related to the administration of vaccines, however, there are few data on the occurrence of neutropenia as a side effect after administration. We present several cases of neutropenia (defined as absolute neutrophil count (ANC) less than 2,000/mm3), after vaccination in hematopoietic progenitor transplant (HPT) recipients performed in our center during 2021.
The primary aim of this systematic review is to objectively evaluate the test performance characteristics of three-dimensional echocardiography (3DE) in measuring left ventricular (LV) volumes and ...ejection fraction (EF).
Despite its growing use in clinical laboratories, the accuracy of 3DE has not been studied on a large scale. It is unclear if this technology offers an advantage over traditional two-dimensional (2D) methods.
We searched for studies that compared LV volumes and EF measured by 3DE and cardiac magnetic resonance (CMR) imaging. A subset of those also compared standard 2D methods with CMR. We used meta-analyses to determine the overall bias and limits of agreement of LV end-diastolic volume (EDV), end-systolic volume (ESV), and EF measured by 3DE and 2D echocardiography (2DE).
Twenty-three studies (1,638 echocardiograms) were included. The pooled biases ± 2 SDs for 3DE were -19.1 ± 34.2 ml, -10.1 ± 29.7 ml, and - 0.6 ± 11.8% for EDV, ESV, and EF, respectively. Nine studies also included data from 2DE, where the pooled biases were -48.2 ± 55.9 ml, -27.7 ± 45.7 ml, and 0.1 ± 13.9% for EDV, ESV, and EF, respectively. In this subset, the difference in bias between 3DE and 2D volumes was statistically significant (p = 0.01 for both EDV and ESV). The difference in variance was statistically significant (p < 0.001) for all 3 measurements.
Three-dimensional echocardiography underestimates volumes and has wide limits of agreement, but compared with traditional 2D methods in these carefully performed studies, 3DE is more accurate for volumes and more precise in all 3 measurements.
The Polyakov loop has been used repeatedly as an order parameter in the deconfinement phase transition in QCD. We argue that, in the confined phase, its expectation value can be represented in terms ...of hadronic states, similarly to the hadron resonance gas model for the pressure. Specifically, L(T)≈1/2∑(α)g(α)e(-Δ(α)/T), where g(α) are the degeneracies and Δ(α) are the masses of hadrons with exactly one heavy quark (the mass of the heavy quark itself being subtracted). We show that this approximate sum rule gives a fair description of available lattice data with N(f)=2+1 for temperatures in the range 150 MeV<T<190 MeV with conventional meson and baryon states from two different models. For temperatures below 150 MeV different lattice results disagree. One set of data can be described if exotic hadrons are present in the QCD spectrum while other sets do not require such states.
The phase partitioning between supercooled liquid water and ice in clouds in the temperature range between 0 and −37°C influences their optical properties and the efficiency of precipitation ...formation. Passive remote sensing observations provide long‐term records of the cloud top phase at a high spatial resolution. Based on the assumption of a cumulative Gaussian distribution of the ice cloud fraction as a function of temperature, we quantify the cloud glaciation temperature (CGT) as the 50th percentile of the fitted distribution function and its variance for different cloud top pressure intervals, obtained by applying an evolutionary algorithm (EA). EAs are metaheuristics approaches for optimization, used in difficult problems where standard approaches are either not applicable or show poor performance. In this case, the proposed EA is applied to 4 years of Pathfinder Atmospheres‐Extended (PATMOS‐x) data, aggregated into boxes of 1° × 1° and vertical layers of 5.5 hPa. The resulting vertical profile of CGT shows a characteristic sickle shape, indicating low CGTs close to homogeneous freezing in the upper troposphere and significantly higher values in the midtroposphere. In winter, a pronounced land‐sea contrast is found at midlatitudes, with lower CGTs over land. Among this and previous studies, there is disagreement on the sign of the land‐sea difference in CGT, suggesting that it is strongly sensitive to the detected and analyzed cloud types, the time of the day, and the phase retrieval method.
Key Points
An evolutionary algorithm has been applied to the estimation of cloud glaciation temperature (CGT)
CGT varies with height, exhibiting a minimum in the upper and a maximum in the midtroposphere
The vertical, latitudinal, and land‐sea variation of the cloud top CGT need to be further explored
•We describe and simulate multi-fractal multi-resolution structures.•Hybrid Diffusion Limited Aggregation - Strange Attractors are proposed.•Super-Cumulus of multi-fractal structures are also ...simulated.
In this paper we propose and simulate novel multi-fractal multi-resolution structures, which arise when hybrid schemes formed by Diffusion Limited Aggregation (DLA) and Strange Attractors (SA) are considered. First, DLA aggregates formed with a given attachment radio (Ra) are generated so that a particle is attached to the aggregate as soon as it is at a distance Ra from any other particle in it. Second, a randomly chosen SA substitutes each particle of the aggregate, by means of a translation and a homothety with uniform scaling 1/Ra, which preserves the SA shape and circumscribes it to the circle of radius Ra. In this process, each SA is adjusted (re-normalized) to the Ra size. The resulting object mimics a cluster of SA, and exhibits a multi-fractal, multi-resolution structure, with a low-resolution profile similar to that of the DLA aggregate, but composed by SA fractals when a higher resolution is considered. We also describe an iteration of this process in order to generate hybrid superclusters, formed by clusters of DLA-SA hybrids.
Parental care directly affects the fitness of individuals because it increases the probability of offspring survival. Therefore, it is expected that parents be particularly motivated to return (i.e., ...exhibit homing behavior) and resume care if they are moved away from offspring by disturbances. Yet, despite several studies on the behavioral ecology of homing in vertebrates, aspects underlying the relationship between movement and offspring care in anurans remain largely unknown. We tested the relative importance of parental care as a driver of homing in
Ikakogi tayrona
, the only glassfrog with demonstrated prolonged maternal care. We carried out translocation experiments in 58 calling males, 23 gravid females, and 19 females caring for eggs. Contrary to expectations, females did not exhibit homing despite the risk of increased offspring mortality. On the other hand, males exhibit homing (they returned from translocation distances up to 320 m), possibly to recover a specific territory that is important for attracting mates. Taken together, our work documents a paradoxical result that may lead to future research testing specific hypothesis about the causes of sex differences in homing and the associated cognitive process.
Significance statement
Studying the relationship between parental care and homing behavior provides a better understanding of how diverse ecological and evolutionary factors influence movement patterns in animals. However, such relationship has been almost untested in anurans, even though their homing behavior and diversity of parental care strategies have separately received great attention from behavioral ecologists. In this study, we found sex differences in homing for the glassfrog
Ikakogi tayrona
. Males are highly motivated to return to a specific territory, possibly to recover a particular place from which they increase mating opportunities. Interestingly, females caring for eggs did not exhibit homing, even if that behavioral decision results in higher mortality rates of offspring in their clutches, as demonstrated in this and other glassfrogs. This work is one of the few studies on homing in anurans that includes a large sample size of females and accounts for both gravid females and females already caring for offspring. Altogether, this study broadens our understanding of how ecological and evolutionary factors can influence homing behavior in vertebrates.
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