776 research outputs found
A Bulk-Parallel Priority Queue in External Memory with STXXL
We propose the design and an implementation of a bulk-parallel external
memory priority queue to take advantage of both shared-memory parallelism and
high external memory transfer speeds to parallel disks. To achieve higher
performance by decoupling item insertions and extractions, we offer two
parallelization interfaces: one using "bulk" sequences, the other by defining
"limit" items. In the design, we discuss how to parallelize insertions using
multiple heaps, and how to calculate a dynamic prediction sequence to prefetch
blocks and apply parallel multiway merge for extraction. Our experimental
results show that in the selected benchmarks the priority queue reaches 75% of
the full parallel I/O bandwidth of rotational disks and and 65% of SSDs, or the
speed of sorting in external memory when bounded by computation.Comment: extended version of SEA'15 conference pape
Bioarchaeological and palaeogenomic portrait of two Pompeians that died during the eruption of Vesuvius in 79 AD
The archaeological site of Pompeii is one of the 54 UNESCO World Heritage sites in Italy, thanks to its
uniqueness: the town was completely destroyed and buried by a Vesuvius’ eruption in 79 AD. In this
work, we present a multidisciplinary approach with bioarchaeological and palaeogenomic analyses
of two Pompeian human remains from the Casa del Fabbro. We have been able to characterize the
genetic profle of the frst Pompeian’ genome, which has strong afnities with the surrounding
central Italian population from the Roman Imperial Age. Our fndings suggest that, despite the
extensive connection between Rome and other Mediterranean populations, a noticeable degree
of genetic homogeneity exists in the Italian peninsula at that time. Moreover, palaeopathological
analyses identifed the presence of spinal tuberculosis and we further investigated the presence of
ancient DNA from Mycobacterium tuberculosis. In conclusion, our study demonstrates the power of
a combined approach to investigate ancient humans and confrms the possibility to retrieve ancient
DNA from Pompeii human remains. Our initial fndings provide a foundation to promote an intensive
and extensive paleogenetic analysis in order to reconstruct the genetic history of population from
Pompeii, a unique archaeological site
The Political Legacy of Entertainment TV
We study the political impact of commercial television in Italy exploiting the staggered introduction of Berlusconi's private TV network, Mediaset, in the early 1980s. We find that individuals with early access to Mediaset all-entertainment content were more likely to vote for Berlusconi's party in 1994, when he first ran for office. The effect persists for five elections and is driven by heavy TV viewers, namely the very young and the elderly. Regarding possible mechanisms, we find that individuals exposed to entertainment TV as children were less cognitively sophisticated and civic-minded as adults, and ultimately more vulnerable to Berlusconi's populist rhetoric.
© 2019 AE
Formación de megacristales de feldespato potásico en el sector sur del batolito Cerro Aspero-Alpa Corral (32°40'S y 64°50'W), Sierras Pampeanas, Córdoba, Argentina
The surrounding rocks of studied area are composed by a metamorphic sequence which includes gneisses, schists, amphibolites, marbles and heterogeneous migmatites in non-conformity intruded by a granitic pluton. All this sequence is dated as having late-Precambric to mid-Paleozoic age.Three facies, mostly of monzogranitic composition, were identified. This study focuses on the porphiric facies; detailed petroestructural studies being performed, the orientation of large microcline crystal and associated microgranular enclaves being measured.Different primary flow directions were determined with track variation of microcline megacrystal and enclaves from subvertical to nearly horizontal positions.These changes have been interpreted as a convective system within the pluton.The presence of a marked planar fabric in microcline megacrystals along with phenomena such a size-variation of crystal, synneusis, crystal trending at the enclave's border and crystal accumulation, proves their early magmatic origin. The enclaves show a cinematic of deformation produced by simple shear.El entorno encajante de la zona estudiada está integrado por una secuencia metamórfica que incluye gneises, esquistos, anfibolitas, calizas cristalinas y migmatitas heterogéneas, intruidas discordantemente por el plutón granÃtico. A este conjunto puede asignársele una edad precámbrica superior-paleozoica media.Se identificaron tres facies, en su mayorÃa de composición monzogranÃtica, diques microgranÃticos a aplÃticos y enclaves. En este trabajo se pone énfasis en la facies porfiroide efectuándose estudios petroestructurales de detalle, tomando como indicadores la orientación de los grandes cristales de microclina y enclaves microgranulares asociados.Se determinaron distintas direcciones de flujo primario con variaciones en la trayectoria de los megacristales de microclina y enclaves desde posiciones subverticales hasta aproximadamente horizontales. Estos cambios han sido interpretados como un sistema convectivo dentro del plutón.La presencia de una marcada fábrica planar en los megacristales de microclina, conjuntamente con fenómenos de gradaciones en el tamaño de cristales, sineusis, alineaciones en los bordes de enclaves y aglomeraciones de cristales evidencian su origen temprano magmático. Los enclaves muestran una cinemática de deformación producida por cizalla simple
Granitos anatécticos de las Sierras Pampeanas de Córdoba (Argentina): edades U-Pb SHRIMP y estudio LAICP- MS de elementos traza en circón de metamorfismo y cristalización diacrónicos
In this contribution we present new U-Pb SHRIMP ages and in
situ LA-ICP-MS trace element geochemistry of zircon crystals from
the RÃo de los Sauces anatectic granite, Córdoba, Argentina. Notable
difference in texture and composition allowed us to identify two
zircon populations in a single granite sample that are interpreted
as reflecting metamorphic and igneous origins. Zircons regarded
as restitic crystals entrained during the melt segregation yielded a
slightly older concordia age of 537.1 ± 4.8 Ma (2σ) than those interpreted
as igneous, dated at 529 ± 6 (2σ) Ma. Inherited metamorphic
zircons are interpreted to represent solid-state growth during high
temperature metamorphism of the Pampean orogeny at the onset
of the anatexis or metamorphic peak. By contrast, igneous zircons
would record the crystallization age of Zr within the RÃo de los Sauces
granite. The textural, compositional and geochronological data of
both zircon populations suggest that the inception of the anatexis,
the melt segregation and crystallization occurred during a short period
of time of 8 myEn este trabajo se aportan nuevos datos de edades U-Pb SHRIMP
y análisis in situ LA-ICP-MS de elementos traza de circones provenientes
del granito RÃo de los Sauces, Córdoba, Argentina. A partir
de marcadas diferencias texturales y composicionales se pudieron
identificar dos poblaciones de circones en una misma muestra del
granito, las cuales sugieren orÃgenes metamórficos e Ãgneos. Las
edades concordia obtenidas en los circones metamórficos e Ãgneos
fueron de 537,1 ± 4,8 Ma (2σ) y 529 ± 6 (2σ) Ma, respectivamente. Se
interpreta que los circones metamórficos representan el crecimiento
en estado sólido durante el metamorfismo de alta temperatura de
la orogenia Pampeana, durante el inicio o el clÃmax de la anatexia.
Por su parte, las edades de los circones Ãgneos representan la edad
de cristalización del granito RÃo de los Sauces. Los datos texturales,
composicionales y geocronológicos de ambas poblaciones de circones
sugieren que el inicio de la anatexia, la segregación del fundido
y la cristalización ocurrieron durante un periodo breve de tiempo de
8 ma
Fate of Salmonella enterica Typhimurium and Listeria monocytogenes in Black Soldier Fly (Hermetia illucens) Larvae Reared on Two Artificial Diets
Ensuring food security is one of the main challenges facing the world over the next 30 years. There is, thus, an urgent need to significantly increase the supply of sustainable protein that can be transformed into animal feed. Proteins from insects offer a valuable alternative. This article presents the results of challenge tests conducted to investigate the dynamics of the microbial load of Salmonella enterica Typhimurium and Listeria monocytogenes in black soldier fly (Hermetia illucens) larvae grown on contaminated substrates. Four separate challenge tests were performed on two substrates: the Gainesville diet and a homemade diet. The challenge test procedure was carried out in accordance with ISO/DIS 20976-2 (under development). The results of this study show that, when grown on contaminated substrates, BSF larvae do not eliminate Salmonella Typhimurium or L. monocytogenes, but can reduce their microbial load. Sanitation processes downstream of the breeding of BSF larvae are, however, required to reduce the microbiological risks of this novel food
Biofortification of selenium in black soldier fly (Hermetia illucens) prepupae reared on seaweed or selenium enriched substrates
Selenium (Se) is an essential trace element for livestock. The element can be supplemented to feed in inorganic or organic Se forms, where the chemical form in the diet affects the accumulation of Se in animal tissues. Insects are known to be natural bioaccumulators of different nutrients, but no studies have so far looked up on the capacity of insects to be biofortified with Se, as a potential future source for Se in feed. In this study, black soldier fly (BSF, Hermetia illucens) larvae were reared on three different substrates: (1) a control substrate (CTR diet) of plant-ingredients (Gainesville diet); (2) Ascophyllum nodosum diet (AN30%), with 30% substitution of the alfalfa meal with the brown algae; and (3) a Se diet, where the CTR diet was fortified with 0.3 mg/kg of Se. All experiments were carried out under dark condition, at 25 °C with 70% relative humidity for two weeks, and the final BSF prepupae were analysed for Se, metals and minerals, and Se species. The mean total Se content in the prepupae reared on Se dietary group was over five times higher compared to the CTR group, whereas lower Se levels were detected in AN30% dietary group. Se speciation analyses showed that organic selenomethionine (SeMet) was the major Se species present, both in CTR and AN30% group. For the Se group, SeMet was accounting for 54% of the total Se. The levels of SeMet were higher in the Se group compared to the CTR group, indicating that BSF prepupae are able to convert inorganic Se to organic Se. The overall results show that the substrates hereby studied affect the total Se and Se species, as well as the levels of other elements, in the BSF prepupae.publishedVersio
Mucosa associated lymphoid tissue lymphoma presenting within a solitary anti-mesenteric dilated segment of ileum: a case report
<p>Abstract</p> <p>Introduction</p> <p>Mucosa associated lymphoid tissue (MALT) lymphoma is the third most common non-Hodgkin's lymphoma subtype. Clinical presentation is often insidious as a low-grade lesion and disease tends to remain localised for a long period of time. Ileal involvement is rare and presentation within an area of focal anti-mesenteric ileal wall dilation simulating a large diverticulum has not been reported.</p> <p>Case presentation</p> <p>A 59-year-old man of Caucasian origin presented to a general surgical outpatients clinic with an 18-month history of intermittent upper abdominal pain following meals. Following normal gastroscopy and abdominal ultrasound, a focally dilated segment of ileum was seen on computed tomography and further clarified by barium investigation. Histology of this segment demonstrated MALT lymphoma of the small bowel.</p> <p>Conclusion</p> <p>A solitary focally dilated segment of ileal wall may be neoplastic in nature and surgical resection needs to be considered.</p
Network sensitivity of systemic risk
A growing body of studies on systemic risk in financial markets has emphasized the key importance of taking into consideration the complex interconnections among financial institutions. Much effort has been put into modeling the contagion dynamics of financial shocks and into assessing the resilience of specific financial markets, either using real network data, reconstruction techniques or simple toy networks. Here, we address the more general problem of how shock propagation dynamics depend on the topological details of the underlying network. To this end, we consider different realistic network topologies, all consistent with balance sheet information obtained from real data on financial institutions. In particular, we consider networks of varying density and with different block structures. In addition, we diversify in the details of the shock propagation dynamics. We confirm that the systemic risk properties of a financial network are extremely sensitive to its network features. Our results can aid in the design of regulatory policies to improve the robustness of financial markets
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