1,388 research outputs found
Computational Progress towards Maximum Distinguishability of Bell States by Linear Evolution and Local Measurement
Many quantum information protocols rely on the ability to distinguish between entangled quantum states known as Bell states. However, theoretical limits exist on the maximal distinguishability of these entangled states using linear evolution and local measurement (LELM) devices. In the case of two particles entangled in multiple qubit variables, the maximum number of distinguishable Bell states is known. However, in the more general case of two particles entangled in multiple qudit variables, only an upper bound is known under additional assumptions. I have written software in Matlab and Mathematica to explore computationally the maximum number of Bell states that can be distinguished in the case of two particles entangled in a qutrit variable, and the case of two particles entangled in both a qutrit and qubit variable. Using code I have written in Mathematica, I have reduced the number of cases to check for sets of 9 qubit x qutrit Bell states from 94,143,280 to 10,365. Further work needs to be done to computationally check these cases for distinguishability by an LELM apparatus
Interpretable estimation of the risk of heart failure hospitalization from a 30-second electrocardiogram
Survival modeling in healthcare relies on explainable statistical models;
yet, their underlying assumptions are often simplistic and, thus, unrealistic.
Machine learning models can estimate more complex relationships and lead to
more accurate predictions, but are non-interpretable. This study shows it is
possible to estimate hospitalization for congestive heart failure by a 30
seconds single-lead electrocardiogram signal. Using a machine learning approach
not only results in greater predictive power but also provides clinically
meaningful interpretations. We train an eXtreme Gradient Boosting accelerated
failure time model and exploit SHapley Additive exPlanations values to explain
the effect of each feature on predictions. Our model achieved a concordance
index of 0.828 and an area under the curve of 0.853 at one year and 0.858 at
two years on a held-out test set of 6,573 patients. These results show that a
rapid test based on an electrocardiogram could be crucial in targeting and
treating high-risk individuals.Comment: 4 pages, 4 figure
The Spitzer c2d Survey of Nearby Dense Cores: VI. The Protostars of Lynds Dark Nebula 1221
Observations of Lynds Dark Nebula 1221 from the Spitzer Space Telescope are
presented. These data show three candidate protostars towards L1221, only two
of which were previously known. The infrared observations also show signatures
of outflowing material, an interpretation which is also supported by radio
observations with the Very Large Array. In addition, molecular line maps from
the Five College Radio Astronomy Observatory are shown.
One-dimensional dust continuum modelling of two of these protostars, IRS1 and
IRS3, is described. These models show two distinctly different protostars
forming in very similar environments. IRS1 shows a higher luminosity and larger
inner radius of the envelope than IRS3. The disparity could be caused by a
difference in age or mass, orientation of outflow cavities, or the impact of a
binary in the IRS1 core.Comment: accepted for publication in Ap
Births from embryos with highly elevated levels of mitochondrial DNA
Measurement of mtDNA copy number might not provide any advantage in embryo prioritization and could lead to a deselection of blastocysts that would result in healthy pregnancies and births. Furthermore, the quantification of mitochondrial functional output in a model of cellular stress might suggest that mitochondria are not clear targets for biomarker identification as it relates to blastocyst viability. Any suggested link between mtDNA levels, mitochondria or their output with blastocyst transfer outcome requires further validation
Constraining Intra-cluster Gas Models with AMiBA13
Clusters of galaxies have been used extensively to determine cosmological
parameters. A major difficulty in making best use of Sunyaev-Zel'dovich (SZ)
and X-ray observations of clusters for cosmology is that using X-ray
observations it is difficult to measure the temperature distribution and
therefore determine the density distribution in individual clusters of galaxies
out to the virial radius. Observations with the new generation of SZ
instruments are a promising alternative approach. We use clusters of galaxies
drawn from high-resolution adaptive mesh refinement (AMR) cosmological
simulations to study how well we should be able to constrain the large-scale
distribution of the intra-cluster gas (ICG) in individual massive relaxed
clusters using AMiBA in its configuration with 13 1.2-m diameter dishes
(AMiBA13) along with X-ray observations. We show that non-isothermal beta
models provide a good description of the ICG in our simulated relaxed clusters.
We use simulated X-ray observations to estimate the quality of constraints on
the distribution of gas density, and simulated SZ visibilities (AMiBA13
observations) for constraints on the large-scale temperature distribution of
the ICG. We find that AMiBA13 visibilities should constrain the scale radius of
the temperature distribution to about 50% accuracy. We conclude that the
upgraded AMiBA, AMiBA13, should be a powerful instrument to constrain the
large-scale distribution of the ICG.Comment: Accepted for publication in The Astrophysical Journal, 12 pages, 9
figure
A novel malaria vaccine candidate antigen expressed in Tetrahymena thermophila
Development of effective malaria vaccines is hampered by the problem of producing correctly folded Plasmodium proteins for use as vaccine components. We have investigated the use of a novel ciliate expression system, Tetrahymena thermophila, as a P. falciparum vaccine antigen platform. A synthetic vaccine antigen composed of N-terminal and C-terminal regions of merozoite surface protein-1 (MSP-1) was expressed in Tetrahymena thermophila. The recombinant antigen was secreted into the culture medium and purified by monoclonal antibody (mAb) affinity chromatography. The vaccine was immunogenic in MF1 mice, eliciting high antibody titers against both N- and C-terminal components. Sera from immunized animals reacted strongly with P. falciparum parasites from three antigenically different strains by immunofluorescence assays, confirming that the antibodies produced are able to recognize parasite antigens in their native form. Epitope mapping of serum reactivity with a peptide library derived from all three MSP-1 Block 2 serotypes confirmed that the MSP-1 Block 2 hybrid component of the vaccine had effectively targeted all three serotypes of this polymorphic region of MSP-1. This study has successfully demonstrated the use of Tetrahymena thermophila as a recombinant protein expression platform for the production of malaria vaccine antigens
Vibration-Controlled Transient Elastography Scores to Predict Liver-Related Events in Steatotic Liver Disease
Importance Metabolic dysfunction–associated steatotic liver disease (MASLD) is currently the most common chronic liver disease worldwide. It is important to develop noninvasive tests to assess the disease severity and prognosis.Objective To study the prognostic implications of baseline levels and dynamic changes of the vibration-controlled transient elastography (VCTE)–based scores developed for the diagnosis of advanced fibrosis (Agile 3+) and cirrhosis (Agile 4) in patients with MASLD.Design, Setting, and Participants This cohort study included data from a natural history cohort of patients with MASLD who underwent VCTE examination at 16 tertiary referral centers in the US, Europe, and Asia from February 2004 to January 2023, of which the data were collected prospectively at 14 centers. Eligible patients were adults aged at least 18 years with hepatic steatosis diagnosed by histologic methods (steatosis in ≥5% of hepatocytes) or imaging studies (ultrasonography, computed tomography or magnetic resonance imaging, or controlled attenuation parameter ≥248 dB/m by VCTE).Main Outcomes and Measures The primary outcome was liver-related events (LREs), defined as hepatocellular carcinoma or hepatic decompensation (ascites, variceal hemorrhage, hepatic encephalopathy, or hepatorenal syndrome), liver transplant, and liver-related deaths. The Agile scores were compared with histologic and 8 other noninvasive tests.Results A total of 16 603 patients underwent VCTE examination at baseline (mean [SD] age, 52.5 [13.7] years; 9600 [57.8%] were male). At a median follow-up of 51.7 (IQR, 25.2-85.2) months, 316 patients (1.9%) developed LREs. Both Agile 3+ and Agile 4 scores classified fewer patients between the low and high cutoffs than most fibrosis scores and achieved the highest discriminatory power in predicting LREs (integrated area under the time-dependent receiver-operating characteristic curve, 0.89). A total of 10 920 patients (65.8%) had repeated VCTE examination at a median interval of 15 (IQR, 11.3-27.7) months and were included in the serial analysis. A total of 81.9% of patients (7208 of 8810) had stable Agile 3+ scores and 92.6% of patients (8163 of 8810) had stable Agile 4 scores (same risk categories at both assessments). The incidence of LREs was 0.6 per 1000 person-years in patients with persistently low Agile 3+ scores and 30.1 per 1000 person-years in patients with persistently high Agile 3+ scores. In patients with high Agile 3+ score at baseline, a decrease in the score by more than 20% was associated with substantial reduction in the risk of LREs. A similar trend was observed for the Agile 4 score, although it missed more LREs in the low-risk group.Conclusions and Relevance Findings of this study suggest that single or serial Agile scores are highly accurate in predicting LREs in patients with MASLD, making them suitable alternatives to liver biopsy in routine clinical practice and in phase 2b and 3 clinical trials for steatohepatitis
Association of maternal Vitamin D status with glucose tolerance and caesarean section in a multi-ethnic Asian cohort: the growing up in Singapore towards healthy outcomes study
10.1371/journal.pone.0142239PLoS ONE10111-16GUSTO (Growing up towards Healthy Outcomes
Forecasting: theory and practice
Forecasting has always been in the forefront of decision making and planning.
The uncertainty that surrounds the future is both exciting and challenging,
with individuals and organisations seeking to minimise risks and maximise
utilities. The lack of a free-lunch theorem implies the need for a diverse set
of forecasting methods to tackle an array of applications. This unique article
provides a non-systematic review of the theory and the practice of forecasting.
We offer a wide range of theoretical, state-of-the-art models, methods,
principles, and approaches to prepare, produce, organise, and evaluate
forecasts. We then demonstrate how such theoretical concepts are applied in a
variety of real-life contexts, including operations, economics, finance,
energy, environment, and social good. We do not claim that this review is an
exhaustive list of methods and applications. The list was compiled based on the
expertise and interests of the authors. However, we wish that our encyclopedic
presentation will offer a point of reference for the rich work that has been
undertaken over the last decades, with some key insights for the future of the
forecasting theory and practice
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