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Causal Correlation Functions and Fourier Transforms: Application in Calculating Pressure Induced Shifts
By adopting a concept from signal processing, instead of starting from the correlation functions which are even, one considers the causal correlation functions whose Fourier transforms become complex. Their real and imaginary parts multiplied by 2 are the Fourier transforms of the original correlations and the subsequent Hilbert transforms, respectively. Thus, by taking this step one can complete the two previously needed transforms. However, to obviate performing the Cauchy principal integrations required in the Hilbert transforms is the greatest advantage. Meanwhile, because the causal correlations are well-bounded within the time domain and band limited in the frequency domain, one can replace their Fourier transforms by the discrete Fourier transforms and the latter can be carried out with the FFT algorithm. This replacement is justified by sampling theory because the Fourier transforms can be derived from the discrete Fourier transforms with the Nyquis rate without any distortions. We apply this method in calculating pressure induced shifts of H2O lines and obtain more reliable values. By comparing the calculated shifts with those in HITRAN 2008 and by screening both of them with the pair identity and the smooth variation rules, one can conclude many of shift values in HITRAN are not correct
Verification of the H2O Linelists with Theoretically Developed Tools
Two basic rules (i.e., the pair identity and the smooth variation rules) resulting from the properties of the energy levels and wave functions of H2O states govern how the spectroscopic parameters vary with the H2O lines within the individually defined groups of lines. With these rules, for those lines involving high j states in the same groups, variations of all their spectroscopic parameters (i.e., the transition frequency, intensity, pressure broadened half-width, pressure-induced shift, and temperature exponent) can be well monitored. Thus, the rules can serve as simple and effective tools to screen the H2O spectroscopic data listed in the HITRAN database and verify the latter's accuracies. By checking violations of the rules occurring among the data within the individual groups, possible errors can be picked up and also possible missing lines in the linelist whose intensities are above the threshold can be identified. We have used these rules to check the accuracies of the spectroscopic parameters and the completeness of the linelists for several important H2O vibrational bands. Based on our results, the accuracy of the line frequencies in HITRAN 2008 is consistent. For the line intensity, we have found that there are a substantial number of lines whose intensity values are questionable. With respect to other parameters, many mistakes have been found. The above claims are consistent with a well known fact that values of these parameters in HITRAN contain larger uncertainties. Furthermore, supplements of the missing line list consisting of line assignments and positions can be developed from the screening results
System reliability calculation of jacket platforms including fatigue and extreme wave loading
Jacket platforms are redundant structures. Therefore, reliability analysis at system level is more applicable than at component level. Conventionally, system reliability analysis is estimated based on either fatigue loading or extreme environmental loading. The purpose of this study is to perform the structural reliability analysis of a jacket platform under both fatigue and extreme loading. In this study the fatigue limit state is defined based on the crack size, which is obtained by a fracture mechanics approach. The probability of failure for each component is calculated by using Monte-Carlo simulation. Important failure paths are identified by using a searching process. The system failure criterion is evaluated by comparing the platform strength and loading distributions in terms of base shear. In order to define a probabilistic formula for load, a global response surface method is adopted to relate the wave height to the response of the structure. A pushover analysis is also carried out to determine the capacity of the platform. Having calculated the structure strength and loading distributions, the annual probability of failure under extreme wave is calculated and compared to the tolerable probability of failure or target reliability. An application of the approach is presented
The quest for sustained multiple morbidity reduction in very low-birth-weight infants: the Antifragility project.
OBJECTIVE: Can a comprehensive, explicitly directive evidence-based guideline for all therapies that might affect the major morbidities of very low-birth-weight (VLBW) infants help a neonatal intensive care unit (NICU) further improve generally favorable morbidity rates? Can Antifragility principles of provider adaptive growth from stressors, enhanced infant risk assessment and adherence to effective therapies minimize unproven treatments and reduce all morbidities?
STUDY DESIGN: Prospectively planned observational trial in VLBW infants: control group born October 2011 to September 2013 and study group October 2013 to September 2015. Multi-disciplinary evidence-based review assigned all NICU treatments into one of four distinct categories: (1) always employ this therapy for VLBW infants, (2) never use this therapy, (3) employ this questionable therapy thoughtfully, only in certain circumstances and (4) this therapy has insufficient evidence of efficacy and safety. Extensive staff education emphasized evidence-based potentially better practice (PBP) selection with compliance checks, appreciation of intertwined co-morbidities and prioritizing infant risk reduction strategies.
RESULTS: Control included 221 infants, mean (s.d.) age 29 (2.6) weeks, birth weight 1129 (257) g and Study included 197 infants, 29 (2.7) weeks, 1093 (292) g. One hundred and four distinct therapies were placed into categories 1 to 4, with 32 specific compliance checks. Overall mean compliance with the process checks during the second era was 70%, high: 100% (exclusive breast milk use), low: 24% (correct pulse oximetry alarm settings). Morbidity and mortality rates did not significantly change during the second era.
CONCLUSIONS: In our NICU with favorable morbidity rates, an expanded effort using a comprehensive therapy guideline for VLBW infants did not further improve outcomes. We need deeper understanding of continuous quality improvement (CQI) fundamentals, therapy compliance, co-morbidity relationships and enhanced sensitivity of risk assessment. Our innovative Antifragility PBP guideline could be useful to other NICUs seeking improvement in VLBW infant morbidities, as we offer a reasoned and concise template of a broad array of therapies categorized efficiently for transparency and review, designed to enhance responsible CQI decision-making
Imaging Drug Uptake by Bioorthogonal Stimulated Raman Scattering Microscopy
Stimulated Raman scattering (SRS) microscopy in tandem with bioorthogonal Raman labelling strategies is set to revolutionise the direct visualisation of intracellular drug uptake. Rational evaluation of a series of Raman-active labels has allowed the identification of highly active labels which have minimal perturbation on the biological efficacy of the parent drug. Drug uptake has been correlated with markers of cellular composition and cell cycle status, and mapped across intracellular structures using dual-colour and multi-modal imaging. The minimal phototoxicity and low photobleaching associated with SRS microscopy has enabled real-time imaging in live cells. These studies demonstrate the potential for SRS microscopy in the drug development process
Release and Establishment of Megamelus scutellaris (Hemiptera: Delphacidae) on Waterhyacinth in Florida
More than 73,000 Megamelus scutellaris (Hemiptera: Delphacidae) were released in Florida over a 2 to 3 yr period at 10 sites in an attempt to establish sustainable populations on waterhyacinth, Eichhornia crassipes Mart. Solms (Commelinales: Pontederiaceae). Insect populations persisted at most sites including those furthest north and consecutive overwintering was confirmed in as many as three times at some sites. Establishment appeared to be promoted at sites with some cover or shading compared to open areas. Insects readily dispersed over short distances which made detection and monitoring difficultFil: Tipping, Philip W.. Invasive Plant Research Laboratory; Estados UnidosFil: Sosa, Alejandro JoaquÃn. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentina. Fundación para el Estudio de Especies Invasivas; ArgentinaFil: Pokorny, Eileen N.. Invasive Plant Research Laboratory; Estados UnidosFil: Foley, Jeremiah. Invasive Plant Research Laboratory; Estados UnidosFil: Schmitz, Don C.. Florida Fish and Wildlife Conservation Commission; Estados UnidosFil: Lane, Jon S.. U.S. Army Corps of Engineers; Estados UnidosFil: Rodgers, Leroy. South Florida Water Management District; Estados UnidosFil: Mccloud, Lori. St. Johns River Water Management District; Estados UnidosFil: Livingston-Way, Pam. St. Johns River Water Management District; Estados UnidosFil: Cole, Matthew S.. St. Johns River Water Management District; Estados UnidosFil: Nichols, Gary. St. Johns River Water Management District; Estados Unido
Active Sampling-based Binary Verification of Dynamical Systems
Nonlinear, adaptive, or otherwise complex control techniques are increasingly
relied upon to ensure the safety of systems operating in uncertain
environments. However, the nonlinearity of the resulting closed-loop system
complicates verification that the system does in fact satisfy those
requirements at all possible operating conditions. While analytical proof-based
techniques and finite abstractions can be used to provably verify the
closed-loop system's response at different operating conditions, they often
produce conservative approximations due to restrictive assumptions and are
difficult to construct in many applications. In contrast, popular statistical
verification techniques relax the restrictions and instead rely upon
simulations to construct statistical or probabilistic guarantees. This work
presents a data-driven statistical verification procedure that instead
constructs statistical learning models from simulated training data to separate
the set of possible perturbations into "safe" and "unsafe" subsets. Binary
evaluations of closed-loop system requirement satisfaction at various
realizations of the uncertainties are obtained through temporal logic
robustness metrics, which are then used to construct predictive models of
requirement satisfaction over the full set of possible uncertainties. As the
accuracy of these predictive statistical models is inherently coupled to the
quality of the training data, an active learning algorithm selects additional
sample points in order to maximize the expected change in the data-driven model
and thus, indirectly, minimize the prediction error. Various case studies
demonstrate the closed-loop verification procedure and highlight improvements
in prediction error over both existing analytical and statistical verification
techniques.Comment: 23 page
Kinetic analysis of bioorthogonal reaction mechanisms using Raman microscopy
Raman spectroscopy is well-suited to the study of bioorthogonal reaction processes because it is a non-destructive technique, which employs relatively low energy laser irradiation, and water is only very weakly scattered in the Raman spectrum enabling live cell imaging. In addition, Raman spectroscopy allows species-specific label-free visualisation; chemical contrast may be achieved when imaging a cell in its native environment without fixatives or stains. Combined with the rapid advances in the field of Raman imaging over the last decade, particularly in stimulated Raman spectroscopy (SRS), this technique has the potential to revolutionise our mechanistic understanding of the biochemical and medicinal chemistry applications of bioorthogonal reactions. Current approaches to the kinetic analysis of bioorthogonal reactions (including heat flow calorimetry, UV-vis spectroscopy, fluorescence, IR, NMR and MS) have a number of practical shortcomings for intracellular applications. We highlight the advantages offered by Raman microscopy for reaction analysis in the context of both established and emerging bioorthogonal reactions, including the copper(i) catalysed azide-alkyne cycloaddition (CuAAC) click reaction and Glaser-Hay coupling
Statistical Mechanical Development of a Sparse Bayesian Classifier
The demand for extracting rules from high dimensional real world data is
increasing in various fields. However, the possible redundancy of such data
sometimes makes it difficult to obtain a good generalization ability for novel
samples. To resolve this problem, we provide a scheme that reduces the
effective dimensions of data by pruning redundant components for bicategorical
classification based on the Bayesian framework. First, the potential of the
proposed method is confirmed in ideal situations using the replica method.
Unfortunately, performing the scheme exactly is computationally difficult. So,
we next develop a tractable approximation algorithm, which turns out to offer
nearly optimal performance in ideal cases when the system size is large.
Finally, the efficacy of the developed classifier is experimentally examined
for a real world problem of colon cancer classification, which shows that the
developed method can be practically useful.Comment: 13 pages, 6 figure
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