Automated assessment of functional lung imaging with 68Ga-ventilation/perfusion PET/CT using iterative histogram analysis

Purpose Functional lung mapping from Ga68-ventilation/perfusion (V/Q) PET/CT, which has been shown to correlate with pulmonary function tests (PFTs), may be beneficial in a number of clinical applications where sparing regions of high lung function is of interest. Regions of clumping in the proximal airways in patients with airways disease can result in areas of focal intense activity and artefact in ventilation imaging. These artefacts may even shine through to subsequent perfusion images and create a challenge for quantitative analysis of PET imaging. We aimed to develop an automated algorithm that interprets the uptake histogram of PET images to calculate a peak uptake value more representative of the global lung volume. Methods Sixty-six patients recruited from a prospective clinical trial underwent both V/Q PET/CT imaging and PFT analysis before treatment. PET images were normalised using an iterative histogram analysis technique to account for tracer hotspots prior to the threshold-based delineation of varying values. Pearson’s correlation between fractional lung function and PFT score was calculated for ventilation, perfusion, and matched imaging volumes at varying threshold values. Results For all functional imaging thresholds, only FEV1/FVC PFT yielded reasonable correlations to image-based functional volume. For ventilation, a range of 10–30% of adapted peak uptake value provided a reasonable threshold to define a volume that correlated with FEV1/FVC (r = 0.54–0.61). For perfusion imaging, a similar correlation was observed (r = 0.51–0.56) in the range of 20–60% adapted peak threshold. Matched volumes were closely linked to ventilation with a threshold range of 15–35% yielding a similar correlation (r = 0.55–0.58). Conclusions Histogram normalisation may be implemented to determine the presence of tracer clumping hotspots in Ga-68 V/Q PET imaging allowing for automated delineation of functional lung and standardisation of functional volume reporting.

Correlation between Yield and Reduced Mass of Raw Materials in Reaction of Fullerene

It turned out that the same regression equation between<br>yield and reduced mass of raw materials holds in<br>cycloaddition, Bingel reaction, and other reactions of<br>fullerene. For the reactions, where the molecular weight of the<br>product exceeds around 1500, reduced mass was obtained<br>from molecular weight adjusted by number of rotatable bonds<br>to show a similar correlation by the regression equation.

Correlation between Yield and Reduced Mass of Raw Materials in Reaction of Fullerene

It turned out that the same regression equation between<br>yield and reduced mass of raw materials holds in<br>cycloaddition, Bingel reaction, and other reactions of<br>fullerene. For the reactions, where the molecular weight of the<br>product exceeds around 1500, reduced mass was obtained<br>from molecular weight adjusted by number of rotatable bonds<br>to show a similar correlation by the regression equation.

A Multicenter Study of the Correlations of Anterior and Posterior Corneal Parameters in Chinese Myopic Patients

In this observational cross-sectional study consisting of 8365 Chinese myopic patients from five different ophthalmic centers, we investigated the correlations between anterior and posterior corneal parameters. Strongly negative anterior-posterior correlations of the mean corneal curvature were observed, with similar correlation coefficients in all myopic groups (R: -0.85 to -0.88). The anterior-posterior correlations of corneal astigmatism (R: 0.65 to 0.75), eccentricity (R: 0.27 to 0.38) and asphericity (R: 0.29 to 0.41) were all positive, with slightly different correlation coefficients between the myopic groups. The anterior-posterior correlations of mean corneal curvature were strongly negative with similar correlation coefficients in all quantile groups of six corneal and anterior chamber parameters (R: -0.84 to -0.91), except Sim Km (R: -0.36 to -0.64). The anterior-posterior correlations of corneal astigmatism were all positive with slightly different correlation coefficients between the quantile groups of SimKm (R: 0.66 to 0.74). The anterior-posterior correlations of corneal eccentricity (R: 0.30 to 0.44) and asphericity (R: 0.33 to 0.45) were positive and slightly different between the quantile groups of SimKm, pachy apex and corneal volume. In conclusion, anterior-posterior correlations of corneal curvature, astigmatism, eccentricity and asphericity can be affected by the severity of myopia and some other corneal parameters.

Entropy Multiparticle Correlation Expansion for a Crystal

As first shown by H. S. Green in 1952, the entropy of a classical fluid of identical particles can be written as a sum of many-particle contributions, each of them being a distinctive functional of all spatial distribution functions up to a given order. By revisiting the combinatorial derivation of the entropy formula, we argue that a similar correlation expansion holds for the entropy of a crystalline system. We discuss how one- and two-body entropies scale with the size of the crystal, and provide fresh numerical data to check the expectation, grounded in theoretical arguments, that both entropies are extensive quantities.

Indirect tone-prominence interaction in Kunming tone sandhi

Kunming exhibits a special kind of interaction between tone and prominence whereby the prosodic headedness is shown to play an indirect role in tone sandhi. Due to higher-ranked tonal faithfulness constraints, lower tones, which are universally unfavored in the head position, do not change to higher tones, and higher tones, which are universally unfavored in the non-head position, do not change to lower tones. Nonetheless, though the unfavored tone-(non-)head correlation does not directly trigger tone sandhi, it indirectly decides whether tone sandhi will take place. Falling tones, inter-syllabic tone segment disagreement, and tonal combinations with identical contours are marked tonal structures in the language. But not all these structures result in tone sandhi. The penalization of these structures is tied to an unfavored tone-(non-)head correlation; only when an undesired tone-(non-)head correlation is involved are the marked tonal structures penalized. The indirect tone-(non-)head interaction observed in Kunming is special but not unique to the language as a similar correlation is found in the Chinese dialects of Dongshi Hakka and Beijing Mandarin.

Psychometric properties of the schedule of growing skills II: Portuguese version

The second version of the Schedule of Growing Skills (SGS-II) was standardized using a sample of 348 UK children, ages 0 to 5 years. It examined ten psychomotor development areas in 14 age ranges. The Portuguese version of SGS-II was published in 2003, re-edited in 2011, and re-published in 2012, but its psychometric properties remained untested. The aim of this study was to evaluate the psychometric properties of the Portuguese version of SGS-II, comparing them with the results of the UK version. A sample of 364 Portuguese children, 193 boys and 172 girls, with an average age of 34.45 months (±18.62) was assessed with the SGS-II. The results have shown suitable psychometric properties of the SGS-II Portuguese version, adequate for the screening of children development. The internal consistency coefficients ranged from adequate to excellent (≥.7) and similar correlation results among the scale’s versions (English and Portuguese) were positive, high, and significant.

Correlation between development of rash and efficacy of EGFR inhibitors: A meta-regression analysis.

e13539 Background: Treatment with Epidermal Growth Factor (EGFR) inhibitors is frequently characterized by the presence of a rash. Previous research has suggested that developing this rash may be associated with improved outcomes. It has been difficult, however, to establish a direct link between occurrence of a rash and tumor response. Rashes are also likely to occur with greater drug exposure and it is possible that they exist as a confounder in the well established relationship between drug exposure/dosing and tumor response. The purpose of this meta-regression analysis is to define whether a correlation exists between the incidence of rash and clinical outcomes including response rate (RR), progression-free survival (PFS) and overall survival (OS) and then examine whether a similar relationship exists with other adverse events as that would suggest that rash occurrence is simply a function of drug dosing and not necessarily an indicator of tumor response. Methods: A literature search for RCT’s involving EGFR inhibitors in non-small cell lung cancer (NSCLC) identified 31 trials. This included 5 trials of Cetuximab, 13 trials of Gefitinib and 13 trials of Erlotinib. Multivariate meta-regression analysis was performed to evaluate whether all rashes (grades 1-5) and severe rashes (grades 3-5) as well as vomiting and neutropenia (two randomly chosen adverse events) may have influenced effect size (measured by RR, PFS and OS) across this cancer type. Results: The presence of severe rashes in the treatment arm was positively correlated with increased PFS (p<0.01) in NSCLC - a similar correlation was also found for risk of vomiting. Additionally, the presence of any rash in the treatment arm was positively correlated with increased OS (p=0.03) in NSCLC – a similar correlation was found for risk of vomiting and neutropenia. Conclusions: The presence of a rash seems to connote an increased likelihood of tumor response and/or survival in NSCLC. The fact that other adverse events (vomiting and neutropenia) are more evident in these responding patients suggests that rash occurrence may simply be a confounder in the EGFR inhibitors’ dose-response relationship as opposed to being independently associated with any tumor response.

Carthusian Choir Stalls and the Misericord in Italy

The majority of choir stalls in Italy lack misericords. Their unusual presence in Piedmont and the Valle d'Aosta most probably reflects their proximity to, and the influence of, northern Europe. This paper reveals that the rare instances of misericords elsewhere in Italy are connected to the Carthusian order. Rather than performing an artistic role, their presence is derived from the specific rubrics of Carthusian liturgy, which legislated in detail on the correct use of misericords. The Cistercians also regulated their use, but a similar correlation cannot be assessed because of the lack of surviving furniture. The Carthusian connection, meanwhile, suggests a purely liturgical function for the carved rests, expanding the study of misericords beyond stylistic and iconographic analyses.