Porting Decision Tree Algorithms to Multicore using FastFlow

The whole computer hardware industry embraced multicores. For these machines, the extreme optimisation of sequential algorithms is no longer sufficient to squeeze the real machine power, which can be only exploited via thread-level parallelism. Decision tree algorithms exhibit natural concurrency that makes them suitable to be parallelised. This paper presents an approach for easy-yet-efficient porting of an implementation of the C4.5 algorithm on multicores. The parallel porting requires minimal changes to the original sequential code, and it is able to exploit up to 7X speedup on an Intel dual-quad core machine.Comment: 18 pages + cove

The Carina Project. VIII. The {\alpha}-element abundances

We have performed a new abundance analysis of Carina Red Giant (RG) stars from spectroscopic data collected with UVES (high resolution) and FLAMES/GIRAFFE (high and medium resolution) at ESO/VLT. The former sample includes 44 RGs, while the latter consists of 65 (high) and ~800 (medium resolution) RGs, covering a significant fraction of the galaxy's RG branch (RGB), and red clump stars. To improve the abundance analysis at the faint magnitude limit, the FLAMES/GIRAFFE data were divided into ten surface gravity and effective temperature bins. The spectra of the stars belonging to the same gravity/temperature bin were stacked. This approach allowed us to increase by at least a factor of five the signal-to-noise ratio in the faint limit (V>20.5mag). We took advantage of the new photometry index cU,B,I introduced by Monelli et al. (2014), as an age and probably a metallicity indicator, to split stars along the RGB. These two stellar populations display distinct [Fe/H] and [Mg/H] distributions: their mean Fe abundances are -2.15$\pm$0.06dex (sig=0.28), and -1.75$\pm$0.03dex (sig=0.21), respectively. The two iron distributions differ at the 75% level. This supports preliminary results by Lemasle et al. (2012) and by Monelli et al. (2014). Moreover, we found that the old and intermediate-age stellar populations have mean [Mg/H] abundances of -1.91$\pm$0.05dex (sig=0.22) and -1.35$\pm$0.03dex (sig=0.22); these differ at the 83% level. Carina's {\alpha}-element abundances agree, within 1sigma, with similar abundances for field Halo stars and for cluster (Galactic, Magellanic) stars. The same outcome applies to nearby dwarf spheroidals and ultra-faint dwarf galaxies, in the iron range covered by Carina stars. Finally, we found evidence of a clear correlation between Na and O abundances, thus suggesting that Carina's chemical enrichment history is quite different than in the globular clusters.Comment: 21 pages, 19 figures, 11 tables, accepted for publication in A&

Non-sutureless minimally invasive aortic valve replacement: mini-sternotomy versus mini-thoracotomy: a series of 1130 patients

OBJECTIVES: Aortic valve replacement through conventional sternotomy still represents the gold-standard surgical approach for aortic valve disease. However, given the increasing number of patients with comorbidities, strategies that can improve operative results are always sought. Minimally invasive aortic valve surgery, although related to a steep learning curve, might be associated with improved post- operative outcomes. The main aim of this study was to assess whether significant differences exist in terms of operative and early results between a mini-sternotomy and a right mini-thoracotomy approach for isolated aortic valve replacement without sutureless technologies. METHODS: This is an observational retrospective multicentre study from nine Italian cardiac centres that analyses prospectively collected data of patients who underwent isolated minimally invasive aortic valve replacement between January 2010 and December 2014. Two approaches are considered (mini-sternotomy and mini-thoracotomy) and compared in terms of operative and early outcomes. RESULTS: After interrogation of the centralized database, a total of 1130 patients were retrieved (854 mini-sternotomy and 276 mini-thoracotomy). Patients in the mini-sternotomy group had a higher risk profile. There was no difference in terms of early mortality; cardiopulmonary bypass and cross-clamp time did not differ significantly between the groups; and a significantly higher number of reoperations for bleeding was observed in the right mini-thoracotomy group. CONCLUSIONS: Both mini-sternotomy and mini-thoracotomy could be performed safely, with low mortality and postoperative morbidity. The mini-thoracotomy approach was associated with a significantly higher rate of reoperation for bleeding. Uptake among cardiac centres was low. Sutureless technologies could potentially increase surgical volume by simplifying the mini-thoracotomy procedure

Winter Survival and Habitat Selection by Translocated Northern Bobwhite in the New Jersey Pine Barrens: Preliminary Results

Northern bobwhite (Colinus virginianus) populations have been experiencing precipitous range-wide declines for more than 50 years; some of the steepest declines occurring in the Mid-Atlantic states. These declines are largely attributed to habitat deterioration from urban sprawl, change in forest management, and intensive farming. This ongoing study aims to evaluate the efficacy of translocating wild bobwhites into the New Jersey Pine Barrens as a means to restore their historic populations. Translocation has proven relatively successful in augmenting bobwhite populations in other regions as well as restoring populations of gallinaceous species. This portion of the study aims to investigate what bobwhites require during winter months (October—March) in the Mid-Atlantic to survive until summer for reproduction. The study site, Pine Island Cranberry Company, is the largest privately owned tract of land (6,800 hectares) in New Jersey, with habitat comprised of pitch pine (Pinus rigida), shortleaf pine (Pinus echinata), scrub oak (Quercus ilicifolia), and early successional forbs and grasses. For three consecutive years (2015—2017) prior to breeding season, we will translocate 80 radio-collared bobwhites (40 male, 40 female) to Pine Island from wild populations in southwest Georgia. These bobwhites are radio-located 3—5 times per week throughout the year while this portion of the study focuses on the winter months. We are collecting microhabitat measurements (e.g., basal density, groundcover, understory, and canopy closure) from 30 random telemetry location points, per covey, per habitat type to characterize winter habitat use. Survival is estimated using staggered-entry Kaplan-Meier analyses and a Cox proportional hazard model in R to determine covariates of daily mortality. We are reporting on the first 2 years of results

Summer Survival of Translocated Northern Bobwhite in the New Jersey Pine Barrens: Preliminary Results

Northern bobwhite (Colinus virginianus) have declined precipitously since the 1960s, largely due to habitat deterioration and changes in land use; some of the highest declines have been observed in the Mid-Atlantic States. In other regions, attempts to augment bobwhite populations have been relatively successful using translocation. As part of a long-term restocking program, focal areas for translocation in the mid-Atlantic region were identified by biologists at a National Bobwhite Conservation Initiative (NBCI) workshop. The objective of this project is to evaluate translocation to restore bobwhite populations in the New Jersey Pine Barrens, a focal area designated with a high ranking for potential bobwhite recovery. The study site, Pine Island Cranberry Co., is the largest privately owned land tract (\u3e6,000 hectares) in New Jersey, with a mix of shortleaf pine (Pinus echinata), pitch pine (P. rigida), scrub oak (Quercus ilicifolia), and early successional forbes and grasses. For three consecutive years (2015—2017) prior to breeding season, we are translocating eighty radio-collared bobwhite (40 male, 40 female) from wild populations in southwest Georgia. These individuals are radio-located 3-5 times per week, year round. We are collecting microhabitat measurements (e.g., groundcover, understory, and canopy closure) and monitoring nests to characterize habitat use, nest site selection, and nest fate. Survival is estimated using staggered-entry Kaplan-Meier analyses and a Cox proportional hazard model in R to determine covariates of daily mortality. Six of 14 nests were successful in summer 2015 (66 known hatches), and 0 of 12 nests were successful in summer 2016. Snake depredation was the cause of 41.7% of failed nests in 2016. Preliminary analyses produce a five-month adult survival rate of 0.455 (SE = 0.138) for summer 2015 and 0.270 (SE = 0.0516) for 2016. Our planned third summer (2017) of data collection will increase our understanding of these disparate survival estimates

Supermassive star formation with non-LTE primordial-gas chemistry

The remnant black holes (BHs) of supermassive stars formed at z > 10 are promising candidates of the seeds for supermassive BHs. They are thought to form in pristine atomic cooling halos in which H_2 cooling is totally suppressed by strong external radiation. Here, we obtain the critical FUV specific intensity J21(cr) (in units of 10-21 erg s-1 Hz-1 sr-1 cm-2) required for supermassive star formation, with non-local thermodynamic equilibrium (non-LTE) primordial-gas chemistry. We consider the non-LTE chemistry with the vibrationally resolved H_2+ kinetics, as well as realistic radiation spectra of galaxies. We find that while the effect of non-LTE H_2+ chemistry is important for soft radiation sources, it is negligible and J21(cr) ∼ 1000 for the hard spectra of young and metal-poor galaxies, considered as typical radiation sources in the early Universe

A bio-imaging signature as a predictor of clinical outcomes in locally advanced pancreatic cancer

Purpose: To evaluate the predictive value of18F-FDG PET/CT semiquantitative parameters of the primary tumour and CA 19-9 levels assessed before treatment in patients with locally advanced pancreatic cancer (LAPC). Methods: Among one-hundred twenty patients with LAPC treated at our institution with initial chemotherapy followed by curative chemoradiotherapy (CRT) from July 2013 to January 2019, a secondary analysis with baseline18F-FDG PET/CT was conducted in fifty-eight patients. Pre-treatment CA 19-9 level and the maximum standardized uptake value (SUVmax), metabolic tumour volume (MTV) and total lesion glycolysis (TLG) of primary tumour were measured. The receiving operating characteristics (ROC) analysis was performed to define the cut-off point of SUVmax, MTV, TLG and CA 19-9 values to use in prediction of early progression (EP), local progression (LP) and overall survival (OS). Areas under the curve (AUCs) were assessed for all variables. Post-test probability was calculated to evaluate the advantage for parameters combination. Results: For EP, CA 19-9 level > 698 U/mL resulted the best marker to identify patient at higher risk with OR of 5.96 (95% CI, 1.66\u201319.47; p = 0.005) and a Positive Predictive Value (PPV) of 61%. For LP, the most significant parameter was TLG (OR 9.75, 95% CI, 1.64\u201357.87, p = 0.012), with PPV of 83%. For OS, the most significant parameter was MTV (OR 3.12, 95% CI, 0.9\u201310.83, p = 0.07) with PPV of 88%. Adding consecutively each of the other parameters, PPV to identify patients at risk resulted further increased (>90%). Conclusions: Pre-treatment CA 19-9 level, as well as MTV and TLG values of primary tumour at baseline18F-FDG PET/CT and their combination, may represent significant predictors of EP, LP and OS in LAPC patients

Vitamin E δ-tocotrienol Sensitizes Human Pancreatic Cancer Cells to TRAIL-induced Apoptosis Through Proteasome-Mediated Down-Regulation of c-FLIP

Background: Vitamin E δ-tocotrienol (VEDT), a vitamin E compound isolated from sources such as palm fruit and annatto beans, has been reported to have cancer chemopreventive and therapeutic effects. Methods: We report a novel function of VEDT in augmenting tumor necrosis factor-related apoptosis-inducing ligand- (TRAIL-) induced apoptosis in pancreatic cancer cells. The effects of VEDT were shown by its ability to trigger caspase-8-dependent apoptosis in pancreatic cancer cells. Results: When combined with TRAIL, VEDT significantly augmented TRAIL-induced apoptosis of pancreatic cancer cells. VEDT decreased cellular FLICE inhibitory protein (c-FLIP) levels without consistently modulating the expression of decoy death receptors 1, 2, 3 or death receptors 4 and 5. Enforced expression of c-FLIP substantially attenuated VEDT/TRAIL-induced apoptosis. Thus, c-FLIP reduction plays an important part in mediating VEDT/TRAIL-induced apoptosis. Moreover, VEDT increased c-FLIP ubiquitination and degradation but did not affect its transcription, suggesting that VEDT decreases c-FLIP levels through promoting its degradation. Of note, degradation of c-FLIP and enhanced TRAIL-induced apoptosis in pancreatic cancer cells were observed only with the anticancer bioactive vitamin E compounds δ-, γ-, and β-tocotrienol but not with the anticancer inactive vitamin E compounds α-tocotrienol and α-, β-, γ-, and δ-tocopherol. Conclusions: c-FLIP degradation is a key event for death receptor-induced apoptosis by anticancer bioactive vitamin E compounds in pancreatic cancer cells. Moreover, VEDT augmented TRAIL inhibition of pancreatic tumor growth and induction of apoptosis in vivo. Combination therapy with TRAIL agonists and bioactive vitamin E compounds may offer a novel strategy for pancreatic cancer intervention

Gapped collective charge excitations and interlayer hopping in cuprate superconductors

We use resonant inelastic x-ray scattering (RIXS) to probe the propagation of plasmons in the electron-doped cuprate superconductor Sr$_{0.9}$La$_{0.1}$CuO$_2$ (SLCO). We detect a plasmon gap of $\sim$~120 meV at the two-dimensional Brillouin zone center, indicating that low-energy plasmons in SLCO are not strictly acoustic. The plasmon dispersion, including the gap, is accurately captured by layered $t$-$J$-$V$ model calculations. A similar analysis performed on recent RIXS data from other cuprates suggests that the plasmon gap is generic and its size is related to the magnitude of the interlayer hopping $t_z$. Our work signifies the three-dimensionality of the charge dynamics in layered cuprates and provides a new method to determine $t_z$.Comment: 17 pages, 10 figures, includes Supplemental Material. Accepted for publication in Physical Review Letter