690 research outputs found
APEnet+: high bandwidth 3D torus direct network for petaflops scale commodity clusters
We describe herein the APElink+ board, a PCIe interconnect adapter featuring
the latest advances in wire speed and interface technology plus hardware
support for a RDMA programming model and experimental acceleration of GPU
networking; this design allows us to build a low latency, high bandwidth PC
cluster, the APEnet+ network, the new generation of our cost-effective,
tens-of-thousands-scalable cluster network architecture. Some test results and
characterization of data transmission of a complete testbench, based on a
commercial development card mounting an Altera FPGA, are provided.Comment: 6 pages, 7 figures, proceeding of CHEP 2010, Taiwan, October 18-2
High-speed data transfer with FPGAs and QSFP+ modules
We present test results and characterization of a data transmission system
based on a last generation FPGA and a commercial QSFP+ (Quad Small Form
Pluggable +) module. QSFP+ standard defines a hot-pluggable transceiver
available in copper or optical cable assemblies for an aggregated bandwidth of
up to 40 Gbps. We implemented a complete testbench based on a commercial
development card mounting an Altera Stratix IV FPGA with 24 serial transceivers
at 8.5 Gbps, together with a custom mezzanine hosting three QSFP+ modules. We
present test results and signal integrity measurements up to an aggregated
bandwidth of 12 Gbps.Comment: 5 pages, 3 figures, Published on JINST Journal of Instrumentation
proceedings of Topical Workshop on Electronics for Particle Physics 2010,
20-24 September 2010, Aachen, Germany(R Ammendola et al 2010 JINST 5 C12019
NaNet: a Low-Latency, Real-Time, Multi-Standard Network Interface Card with GPUDirect Features
While the GPGPU paradigm is widely recognized as an effective approach to
high performance computing, its adoption in low-latency, real-time systems is
still in its early stages.
Although GPUs typically show deterministic behaviour in terms of latency in
executing computational kernels as soon as data is available in their internal
memories, assessment of real-time features of a standard GPGPU system needs
careful characterization of all subsystems along data stream path.
The networking subsystem results in being the most critical one in terms of
absolute value and fluctuations of its response latency.
Our envisioned solution to this issue is NaNet, a FPGA-based PCIe Network
Interface Card (NIC) design featuring a configurable and extensible set of
network channels with direct access through GPUDirect to NVIDIA Fermi/Kepler
GPU memories.
NaNet design currently supports both standard - GbE (1000BASE-T) and 10GbE
(10Base-R) - and custom - 34~Gbps APElink and 2.5~Gbps deterministic latency
KM3link - channels, but its modularity allows for a straightforward inclusion
of other link technologies.
To avoid host OS intervention on data stream and remove a possible source of
jitter, the design includes a network/transport layer offload module with
cycle-accurate, upper-bound latency, supporting UDP, KM3link Time Division
Multiplexing and APElink protocols.
After NaNet architecture description and its latency/bandwidth
characterization for all supported links, two real world use cases will be
presented: the GPU-based low level trigger for the RICH detector in the NA62
experiment at CERN and the on-/off-shore data link for KM3 underwater neutrino
telescope
Effect of weather on temporal pain patterns in patients with temporomandibular disorders and migraine
Patients with masticatory muscle pain and migraine typically report that the intensity of pain fluctuates over time and is affected by weather changes. Weather variables, such as ambient temperature and humidity, may vary significantly depending on whether the individual is outdoor or indoor. It is, therefore, important to assess these variables at the individual level using portable monitors, during everyday life. This study aimed to determine and compare the temporal patterns of pain in individuals affected with facial and head pain and to investigate its relation with weather changes. Eleven patients (27·3 ± 7·4 years) with chronic masticatory muscle pain (MP) and twenty (33·1 ± 8·7 years) with migraine headache (MH) were asked to report their current pain level on a visual analogue scale (VAS) every hour over fourteen consecutive days. The VAS scores were collected using portable data-loggers, which were also used to record temperature, atmospheric pressure and relative humidity. VAS scores varied markedly over time in both groups. Pain VAS scores fluctuate less in the MP group than in the MH group, but their mean, minimum and maximum values were higher than those of migraine patients (all P < 0·05). Pain scores <2 cm were more common in the MH than in the MP group (P < 0·001). Perceived intensity of pain was negatively associated with atmospheric pressure in the MP group and positively associated with temperature and atmospheric in the MH group. Our results reveal that patients with masticatory muscle pain and patients with migraine present typical temporal pain patterns that are influenced in a different way by weather changes
High-efficiency mixing of fine powders via sound assisted fluidized bed for metal foam production by an innovative cold gas dynamic spray deposition method
Metal foams are an interesting class of materials with very low specific weight and unusual physical, mechanical and acoustic properties due to the porous structure (1). These materials are currently manufactured by means of several conventional processes (2), limited by the impossibility to produce foams with complex geometry. This paper deals with the study of an innovative method to produce complex shaped precursors for aluminum foams through cold gas dynamic spray deposition process (CGDS), aluminum alloy (AlSi12) and titanium-hydride (TiH2) being the metal and the blowing agent, respectively. However, the success of this approach strongly depends on the achievement of a homogenous and deep mixing between AlSi12 and TiH2 fine powders, belonging to group C of Geldart’s classification. Classical mixing methods (such as tumbling mixers, convective mixers, high-shear mixers, etc.) are suitable for large non-cohesive particles (\u3e 30µm) but not for micronic particles (3), agglomerated due to strong interparticle forces. Alternatively, new wet and dry mixing techniques have been proposed for fine particles (4), suffering from different disadvantages: additional steps of filtration/drying are needed for wet methods, whereas, dry methods generally involves the reduction of the granulometry and the damaging or contamination of the original powders. The sound assisted fluidization technology (140dB-80Hz) has been adopted in this work to overcome the technical issues of mixing cohesive powders (5), thus obtaining a mixing to the scale of the primary particles in a simple, economic, not intrusive and not destructive way (the properties and morphology of the original particles were preserved). Therefore, the mixed powders were then sprayed by means of the proposed CGDS process on a stainless steel sheet to obtain the precursor. This was then heated up in a furnace at 600°C for 10 minutes to obtain the foam. In particular, two different types of mixtures with 1 wt% and 2.5 wt% of TiH2 were investigated; moreover, air compressed as well as helium were used as CGDS carrier gas in order to ensure a higher impact velocity and a better compacting of the powders. A very efficient mixing of powders has been achieved as confirmed by SEM/EDS analysis performed on samples taken from the sound assisted fluidized bed (Fig.1a) and by the time-dependence of the mixing degree (Fig.1b). Macrographs of created porous structures (Fig.2) showed that the coupling of sound assisted fluidization and CGDS process under optimal conditions is a promising and effective technique in manufacturing aluminum precursors for metal foams.
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Salmonella Typhimurium and Pseudomonas aeruginosa respond differently to the Fe chelator deferiprone and to some novel deferiprone derivatives
GPU-based Real-time Triggering in the NA62 Experiment
Over the last few years the GPGPU (General-Purpose computing on Graphics
Processing Units) paradigm represented a remarkable development in the world of
computing. Computing for High-Energy Physics is no exception: several works
have demonstrated the effectiveness of the integration of GPU-based systems in
high level trigger of different experiments. On the other hand the use of GPUs
in the low level trigger systems, characterized by stringent real-time
constraints, such as tight time budget and high throughput, poses several
challenges. In this paper we focus on the low level trigger in the CERN NA62
experiment, investigating the use of real-time computing on GPUs in this
synchronous system. Our approach aimed at harvesting the GPU computing power to
build in real-time refined physics-related trigger primitives for the RICH
detector, as the the knowledge of Cerenkov rings parameters allows to build
stringent conditions for data selection at trigger level. Latencies of all
components of the trigger chain have been analyzed, pointing out that
networking is the most critical one. To keep the latency of data transfer task
under control, we devised NaNet, an FPGA-based PCIe Network Interface Card
(NIC) with GPUDirect capabilities. For the processing task, we developed
specific multiple ring trigger algorithms to leverage the parallel architecture
of GPUs and increase the processing throughput to keep up with the high event
rate. Results obtained during the first months of 2016 NA62 run are presented
and discussed
Hyperthermic intraperitoneal chemotherapy and colorectal cancer: From physiology to surgery
The pursuit of this paper is to collect principal reviews and systematic reviews about hyperthermic intraperitoneal chemotherapy (HIPEC) and cytoreductive surgery (CRS) used in colorectal cancer (CRC). We focus on principal biological aspects of CRC, hyperthermia effects, and surgical procedures. We searched PubMed/MEDLINE for the principal reviews and systematic reviews published from 2010 to 2021 regarding the bimodal treatment (CRS + HIPEC) against local and advanced CRC. In the literature, from several studies, it seems that the efficacy of bimodal treatment with an accurate CRS can extend overall survival. Despite these studies, there are not still any straight guidelines more detailed and scheduled about the use of combined treatment in patients with CRC. Even if the concept is still not very clear and shared, after a careful evaluation of the published data, and after some technical and pathophysiological descriptions, we concluded that it is possible to improve the overall survival and quality of life and to reduce the tumor relapse in patients affected by locally advanced (pT4) CRC with peritoneal metastases
A multibiomarker approach to evaluate the impact of anthropogenic contaminants on the ecotoxicological status of honey bees, Apis mellifera
A rapid decline of Apis mellifera, a keystone pollinator of wild plant species and
agricultural crops, was recorded worldwide in recent years. The massive use of
insecticides and fungicides in agriculture associated with pollution generated by
other human activities and presence of parasites can cause toxicological effects in
bees including a decrease of the immune defences, leading to the collapse of the
colonies. Effective assessment of the ecotoxicological impacts of anthropogenic
contaminants requires an approach that combines different biomarkers that enable
a more precise diagnosis of exposure to environmental stressors through a
combination of different biological responses. The aim of this study was to
develop and apply a set of biomarkers to study the ecotoxicological status of
honey bees. In the first phase, we investigated in the laboratory the effects of
EMS, cadmium and a commercial fungicide (azoxistrobin 18.2% and
ciproconazole 7.3%) in adult honey bees, evaluating eventual variation in
glutathione S-transferase (GST), carboxylesterase (CaE), acetylcholinesterase
(AChE) activities, alkaline phosphatase (ALP), lysozyme, erythrocyte nuclear
abnormalities (ENA) assay and differential haemocytes count (DHC). Genotoxic
effects, as well as alteration of the immune system, were found in bees treated
with EMS, cadmium or the fungicide. Cadmium and the fungicide also inhibited
AChE and CaE activities, GST was induced by all the compounds investigated. In
the second phase, adult honey bees were collected from apiaries located in four
environments characterized by different chemical input: a wooded environment
(low input), an urban site, an orchard and a cultivated countryside site. Honey
bees from the urban site were also collected and analyzed before and after
treatment for parasites. ENA assay showed that bees taken from the countryside
and the orchard had a greater number of abnormalities compared to the forest,
confirming the presence of genotoxic substances in agricultural environments
compared to control environments. GST activity was induced in bees from the
urban environment, AChE was inhibited in the countryside compared to the forest,
suggesting the presence of substances with neurotoxic effect in this environment.
ALP activity was induced in all sites in comparison to wooded one. The bees
collected after the parasites treatment showed an increase for GST activity as well
as AChE inhibition
Exploring a New Paradigm for Accelerators and Large Experimental Apparatus Control Systems
International audienceThe integration of web technologies and web services has been, in the recent years, one of the major trends in upgrading and developing control systems for accelerators and large experimental apparatuses. Usually, web technologies have been introduced to complement the control systems with smart add-ons and user friendly services or, for instance, to safely allow access to the control system to users from remote sites. In spite of this still narrow spectrum of employment, some software technologies developed for high performance web services, although originally intended and optimized for these particular applications, deserve some features that would allow their deeper integration in a control system and, eventually, use them to develop some of the control system's core components. In this paper we present the conclusion of the preliminary investigations of a new paradigm for an accelerator control system and associated machine data acquisition system (DAQ), based on a synergic combination of network distributed cache memory and a non-relational key/value database. We investigated these technologies with particular interest on performances, namely speed of data storage and retrieve for the network memory, data throughput and queries execution time for the database and, especially, how much this performances can benefit from their inherent scalability. The work has been developed in a collaboration between INFN-LNF and INFN-Roma Tor Vergata
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