Nonlinear Prediction of Solar Cycle 24 Kilcik, A; Anderson, C. N. K; Rozelot, J. P ...
Astrophysical journal/The Astrophysical journal,
03/2009, Letnik:
693, Številka:
2
Journal Article
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Sunspot activity is highly variable and challenging to forecast. Yet forecasts are important, since peak activity has profound effects on major geophysical phenomena including space weather ...(satellite drag, telecommunications outages) and has even been correlated speculatively with changes in global weather patterns. This paper investigates trends in sunspot activity, using new techniques for decadal-scale prediction of the present solar cycle (cycle 24). First, Hurst exponent H analysis is used to investigate the autocorrelation structure of the putative dynamics; then the Sugihara-May algorithm is used to predict the ascension time and the maximum intensity of the current sunspot cycle. Here we report H = 0.86 for the complete sunspot number data set (1700-2007) and H = 0.88 for the reliable sunspot data set (1848-2007). Using the Sugihara-May algorithm analysis, we forecast that cycle 24 will reach its maximum in 2012 December at approximately 87 sunspot units.
Atopic or immunoglobulin E (IgE)-mediated diseases include the common disorders of asthma, atopic dermatitis and allergic rhinitis. Chromosome 13q14 shows consistent linkage to atopy and the total ...serum IgE concentration. We previously identified association between total serum IgE levels and a novel 13q14 microsatellite (USAT24G1; ref. 7) and have now localized the underlying quantitative-trait locus (QTL) in a comprehensive single-nucleotide polymorphism (SNP) map. We found replicated association to IgE levels that was attributed to several alleles in a single gene, PHF11. We also found association with these variants to severe clinical asthma. The gene product (PHF11) contains two PHD zinc fingers and probably regulates transcription. Distinctive splice variants were expressed in immune tissues and cells.
To examine whether U.S. radiologists' interpretive volume affects their screening mammography performance.
Annual interpretive volume measures (total, screening, diagnostic, and screening focus ratio ...of screening to diagnostic mammograms) were collected for 120 radiologists in the Breast Cancer Surveillance Consortium (BCSC) who interpreted 783 965 screening mammograms from 2002 to 2006. Volume measures in 1 year were examined by using multivariate logistic regression relative to screening sensitivity, false-positive rates, and cancer detection rate the next year. BCSC registries and the Statistical Coordinating Center received institutional review board approval for active or passive consenting processes and a Federal Certificate of Confidentiality and other protections for participating women, physicians, and facilities. All procedures were compliant with the terms of the Health Insurance Portability and Accountability Act.
Mean sensitivity was 85.2% (95% confidence interval CI: 83.7%, 86.6%) and was significantly lower for radiologists with a greater screening focus (P = .023) but did not significantly differ by total (P = .47), screening (P = .33), or diagnostic (P = .23) volume. The mean false-positive rate was 9.1% (95% CI: 8.1%, 10.1%), with rates significantly higher for radiologists who had the lowest total (P = .008) and screening (P = .015) volumes. Radiologists with low diagnostic volume (P = .004 and P = .008) and a greater screening focus (P = .003 and P = .002) had significantly lower false-positive and cancer detection rates, respectively. Median invasive tumor size and proportion of cancers detected at early stages did not vary by volume.
Increasing minimum interpretive volume requirements in the United States while adding a minimal requirement for diagnostic interpretation could reduce the number of false-positive work-ups without hindering cancer detection. These results provide detailed associations between mammography volumes and performance for policymakers to consider along with workforce, practice organization, and access issues and radiologist experience when reevaluating requirements.
α-Synuclein (α-syn) is the major component of filamentous Lewy bodies found in the brains of patients diagnosed with Parkinson's disease (PD). Recent studies demonstrate that, in addition to the ...wild-type sequence, α-syn is found in several modified forms, including truncated and phosphorylated species. Although the mechanism by which the neuronal loss in PD occurs is unknown, aggregation and fibril formation of α-syn are considered to be key pathological features. In this study, we analyze the rates of fibril formation and the monomer–fibril equilibrium for eight disease-associated truncated and phosphorylated α-syn variants. Comparison of the relative rates of aggregation reveals a strong monotonic relationship between the C-terminal charge of α-syn and the lag time prior to the observation of fibril formation, with truncated species exhibiting the fastest aggregation rates. Moreover, we find that a decrease in C-terminal charge shifts the equilibrium to favor the fibrillar species. An analysis of these findings in the context of linear growth theories suggests that the loss of the charge-mediated stabilization of the soluble state is responsible for the enhanced aggregation rate and increased extent of fibril fraction. Therefore, C-terminal charge is kinetically and thermodynamically protective against α-syn polymerization and may provide a target for the treatment of PD.
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Mutations in NLRP3 (CIAS1) are identified in a continuum of related inflammatory disorders, known as cryopyrinopathies since NLRP3 codes for the protein cryopyrin. Approximately 40% of patients with ...classic presentation lack mutations in the coding region of NLRP3 suggesting heterogeneity or epigenetic factors. Cryopyrin is a key regulator of proinflammatory cytokine release. Therefore, variations in the NLRP3 promoter sequence may have effects on disease state in patients with cryopyrinopathies and other inflammatory diseases. In this report, we confirmed three 5'-untranslated region splice forms with two separate transcriptional start sites, and identified potential promoter regions and six new DNA promoter variants. One variant is unique to a mutation negative cryopyrinopathy patient and increases in vitro gene expression. Additional studies can now be performed to further characterize the NLRP3 promoter and sequence variants, which will lead to better understanding of the regulation of NLRP3 expression and its role in disease.
This study evaluated the results of high-dose therapy followed by autologous bone marrow or peripheral-blood stem-cell transplantation for patients with follicular low-grade non-Hodgkin's lymphoma.
...We performed a retrospective review of 100 patients undergoing autologous transplantation for follicular low-grade lymphoma between April 22, 1983 and December 31, 1993.
Sixty-seven patients remained alive and 48 were failure-free. The median follow-up duration of surviving patients was 2.6 years (range, 1.0 to 11.7). There were eight (8%) deaths within 100 days of transplantation. Six additional patients died of nonrelapse causes up to 912 days after transplantation. Overall survival at 4 years was estimated to be 65% (95% confidence interval CI, 54% to 75%) and failure-free survival was estimated to be 44% (95% CI, 33% to 55%). There was no definite evidence of a plateau in the failure-free survival curve. The only factor significantly associated with overall survival and failure-free survival was the number of chemotherapy regimen received before transplantation. No significant differences in outcome were observed between patients with follicular small cleaved-cell lymphoma and follicular mixed lymphoma, or between patients who received peripheral-blood stem-cell transplants and unpurged autologous bone marrow transplants.
Prolonged failure-free survival is possible following high-dose therapy and autologous hematopoietic rescue for follicular low-grade lymphoma. It is unclear whether patients are cured with this therapy or if survival is prolonged.
Magnetic perturbations on ground at high latitudes are directly associated only with the divergence‐free component of the height‐integrated horizontal ionospheric current, J⊥,df. Here we show how ...J⊥,df can be expressed as the total horizontal current J⊥ minus its curl‐free component, the latter being completely determined by the global Birkeland current pattern. Thus, in regions where J⊥=0, the global Birkeland current distribution alone determines the local magnetic perturbation. We show with observations from ground and space that in the polar cap, the ground magnetic field perturbations tend to align with the Birkeland current contribution in darkness but not in sunlight. We also show that in sunlight, the magnetic perturbations are typically such that the equivalent overhead current is antiparallel to the convection, indicating that the Hall current system dominates. Thus, the ground magnetic field in the polar cap relates to different current systems in sunlight and in darkness.
Key Points
Polar cap magnetic field perturbations relate to different current systems in sunlight and darkness
Polar cap magnetic field perturbations relate to Birkeland currents in darkness
Polar cap magnetic field perturbations relate to Hall currents in sunlight
ABSTRACT
We study the polarization properties of extragalactic sources at 95 and 150 GHz in the SPTpol 500 deg2 survey. We estimate the polarized power by stacking maps at known source positions, and ...correct for noise bias by subtracting the mean polarized power at random positions in the maps. We show that the method is unbiased using a set of simulated maps with similar noise properties to the real SPTpol maps. We find a flux-weighted mean-squared polarization fraction 〈p2〉 = 8.9 ± 1.1 × 10−4 at 95 GHz and 6.9 ± 1.1 × 10−4 at 150 GHz for the full sample. This is consistent with the values obtained for a subsample of active galactic nuclei. For dusty sources, we find 95 per cent upper limits of 〈p2〉95 < 16.9 × 10−3 and 〈p2〉150 < 2.6 × 10−3. We find no evidence that the polarization fraction depends on the source flux or observing frequency. The 1σ upper limit on measured mean-squared polarization fraction at 150 GHz implies that extragalactic foregrounds will be subdominant to the CMB E and B mode polarization power spectra out to at least ℓ ≲ 5700 (ℓ ≲ 4700) and ℓ ≲ 5300 (ℓ ≲ 3600), respectively, at 95 (150) GHz.
Summary Background & aims Muscle wasting commonly occurs in COPD, negatively affecting outcome. The aim was to examine the net whole-body protein synthesis response to two milk protein meals with ...comparable absorption rates (hydrolyzed casein (hCAS) vs. hydrolyzed whey (hWHEY)) and the effects of co-ingesting leucine. Methods Twelve COPD patients (GOLD stage II–IV) with nutritional depletion, were studied following intake of a 15 g hCAS or hWHEY protein meal with or without leucine-co-ingestion, according to a double-blind randomized cross-over design. The isotopic tracers L-ring-2 H5 -Phenylalanine, L-ring-2 H2 -Tyrosine, L-2 H3 -3-Methylhistidine (given via continuous intravenous infusion), and L-15 N-Phenylalanine (added to the protein meals) were used to measure endogenous whole-body protein breakdown (WbPB), whole-body protein synthesis (WbPS), net protein synthesis (NetPS), splanchnic extraction and myofibrillar protein breakdown (MPB). Analyses were done in arterialized-venous plasma by LC/MS/MS. Results WbPS was greater after intake of the hCAS protein meal ( P < 0.05) whereas the hWHEY protein meal reduced WbPB more ( P < 0.01). NetPS was stimulated comparably, with a protein conversion rate greater than 70%. Addition of leucine did not modify the insulin, WbPB, WbPS or MPB response. Conclusions Hydrolyzed casein and whey protein meals comparably and efficiently stimulate whole-body protein anabolism in COPD patients with nutritional depletion without an additional effect of leucine co-ingestion. This trial was registered at clinicaltrials.gov as NCT01154400.
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