Evaluating and Optimizing IP Lookup on Many core Processors

International audienceIn recent years, there has been a growing interest in multi/many core processors as a target architecture for high performance software router. Because of its key position in routers, hardware IP lookup implementation has been intensively studied with TCAM and FPGA based architecture. However, increasing interest in software implementation has also been observed. In this paper, we evaluate the performance of software only IP lookup on a many core chip, the TILEPro64 processor. For this purpose we have implemented two widely used IP lookup algorithms, DIR-24-8-BASIC and Tree Bitmap. We evaluate the performance of these two algorithms over the TILEPro64 processor with both synthetic and real-world traces. After a detailed analysis, we propose a hybrid scheme which provides high lookup speed and low worst case update overhead. Our work shows how to exploit the architectural features of TILEPro64 to improve the performance, including many optimization in both single-core and parallelism aspects. Experiment results show by using only 18 cores, we can achieve a lookup throughput of 60Mpps (almost 40Gbps) with low power consumption, which demonstrates great performance potentials in many core processor

Local strategies for China's carbon mitigation: An investigation of Chinese city-level CO2 emissions

This paper provides a systematic analysis that identifies the driving forces of carbon dioxide (CO2) emissions of 286 Chinese prefecture-level cities in 2012. The regression analysis confirms the economic scale and structure effects on cities' CO2 emissions in China. If China's annual economic growth continues at the rate of 7%, CO2 emissions will increase by about 6% annually. In addition, climate conditions, urbanization and public investment in R&D are identified as important driving forces to increase the CO2 emissions of Chinese cities. While an increment of the urbanization rate by 1% increases the CO2 emissions by about 0.9%; An increase in R&D investment by 1% can help reduce CO2 emissions by 0.21%. As cities in our study vary greatly based on their industry composition, development stage and geographical location, the patterns of their CO2 emissions are also variable. Our study improves the comprehensiveness and accuracy of previous carbon accounting method by distinguishing the scope 1 and scope 2 CO2 emissions and establishing a high spatial resolution dataset of CO2 emissions (CHRED). The analysis covers almost all Chinese prefectural cities and derives useful implications for China's low carbon development

BioNMT: A Biomedical Neural Machine Translation System

To solve the problem of translation of professional vocabulary in the biomedical field and help biological researchers to translate and understand foreign language documents, we proposed a semantic disambiguation model and external dictionaries to build a novel translation model for biomedical texts based on the transformer model. The proposed biomedical neural machine translation system (BioNMT) adopts the sequence-to-sequence translation framework, which is based on deep neural networks. To construct the specialized vocabulary of biology and medicine, a hybrid corpus was obtained using a crawler system extracting from universal corpus and biomedical corpus. The experimental results showed that BioNMT which composed by professional biological dictionary and Transformer model increased the bilingual evaluation understudy (BLEU) value by 14.14%, and the perplexity was reduced by 40%. And compared with Google Translation System and Baidu Translation System, BioNMT achieved better translations about paragraphs and resolve the ambiguity of biomedical name entities to greatly improved

PEARL: a programmable virtual router platform

International audienceProgrammable routers supporting virtualization are a key building block for bridging the gap between new Internet protocols and their deployment in real operational networks. This article presents the design and implementation of PEARL, a programmable virtual router platform with relatively high performance. It offers high flexibility by allowing users to control the configuration of both hardware and software data paths. The platform makes use of fast lookup in hardware and software exceptions in commodity multicore CPUs to achieve highspeed packet processing. Multiple isolated packet streams and virtualization techniques ensure isolation among virtual router instances

A Wideband Low-Profile All-Metal Cavity Slot Antenna With Filtering Performance for Space-Borne SAR Applications

This letter presents a wideband all-metal cavity slot antenna with a filtering performance for space-borne synthetic aperture radar applications. The proposed antenna element consists of a metal cavity and several radiation slots. It is fabricated by aluminium through milling and welding process, the techniques of which are reliable for the space environment. Benefiting from multiresonances of the cavity and slots, the antenna is able to obtain a wide operating bandwidth. Additionally, the cavity has a very low profile of 2.8 mm, equivalent to 0.093 wavelength at the central operating frequency. An 8 × 12 antenna array is designed, fabricated, and measured for performance verification. The measured impedance bandwidth with S 11 <;-10 dB is achieved from 7.2 to 12.2 GHz, giving a relative bandwidth of 51%. Furthermore, it shows good filtering characteristic with more than 20 dB out-of-band rejections, which is capable to suppress unwanted interferences and contribute to a good electromagnetic compatibility desig

Genetic dissection of QTLs for oil content in four maize DH populations

Oil is one of the main components in maize kernels. Increasing the total oil content (TOC) is favorable to optimize feeding requirement by improving maize quality. To better understand the genetic basis of TOC, quantitative trait loci (QTL) in four double haploid (DH) populations were explored. TOC exhibited continuously and approximately normal distribution in the four populations. The moderate to high broad-sense heritability (67.00-86.60%) indicated that the majority of TOC variations are controlled by genetic factors. A total of 16 QTLs were identified across all chromosomes in a range of 3.49-30.84% in term of phenotypic variation explained. Among them, six QTLs were identified as the major QTLs that explained phenotypic variation larger than 10%. Especially, qOC-1-3 and qOC-2-3 on chromosome 9 were recognized as the largest effect QTLs with 30.84% and 21.74% of phenotypic variance, respectively. Seventeen well-known genes involved in fatty acid metabolic pathway located within QTL intervals. These QTLs will enhance our understanding of the genetic basis of TOC in maize and offer prospective routes to clone candidate genes regulating TOC for breeding program to cultivate maize varieties with the better grain quality

Human tribbles-1 controls proliferation and chemotaxis of smooth muscle cells via MAPK signaling pathways

Migration and proliferation of smooth muscle cells are key to a number of physiological and pathological processes, including wound healing and the narrowing of the vessel wall.Previous work has shown links between inflammatory stimuli and vascular smooth muscle cell proliferation and migration through mitogen activated protein kinase (MAPK) activation, though the molecular mechanisms of this process are poorly understood. Here we report that tribbles-1, a recently described modulator of MAPK activation controls vascular smooth muscle cell proliferation and chemotaxis via the Jun Kinase pathway. Our findings demonstrate that this regulation takes place via direct interactions between tribbles-1 and MKK4/SEK1, a Jun activator kinase. The activity of this kinase is dependent on tribbles-1 levels, whilst the activation and the expression of MKK4/SEK1 is not. In addition, tribbles-1 expression is elevated in human atherosclerotic arteries compared to non-atherosclerotic controls, suggesting that this protein may pay a role in disease in vivo. In summary, the data presented here suggest an important regulatory role for trb-1 in vascular smooth muscle cell biology

Notch1 Pathway Protects against Burn-Induced Myocardial Injury by Repressing Reactive Oxygen Species Production through JAK2/STAT3 Signaling

Oxidative stress plays an important role in burn-induced myocardial injury, but the cellular mechanisms that control reactive oxygen species (ROS) production and scavenging are not fully understood. This study demonstrated that blockade of Notch signaling via knockout of the transcription factor RBP-J or a pharmacological inhibitor aggravated postburn myocardial injury, which manifested as deteriorated serum CK, CK-MB, and LDH levels and increased apoptosis in vitro and in vivo. Interruption of Notch signaling increased intracellular ROS production, and a ROS scavenger reversed the exacerbated myocardial injury after Notch signaling blockade. These results suggest that Notch signaling deficiency aggravated postburn myocardial injury through increased ROS levels. Notch signaling blockade also decreased MnSOD expression in vitro and in vivo. Notably, Notch signaling blockade downregulated p-JAK2 and p-STAT3 expression. Inhibition of JAK2/STAT3 signaling with AG490 markedly decreased MnSOD expression, increased ROS production, and aggravated myocardial injury. AG490 plus GSI exerted no additional effects. These results demonstrate that Notch signaling protects against burn-induced myocardial injury through JAK2/STAT3 signaling, which activates the expression of MnSOD and leads to decreased ROS levels

Maize ABP9 enhances tolerance to multiple stresses in transgenic Arabidopsis by modulating ABA signaling and cellular levels of reactive oxygen species

The phytohormone abscisic acid (ABA) and reactive oxygen species (ROS) play critical roles in mediating abiotic stress responses in plants. It is well known that ABA is involved in the modulation of ROS levels by regulating ROS-producing and ROS-scavenging genes, but the molecular mechanisms underlying this regulation are poorly understood. Here we show that the expression of maize ABP9 gene, which encodes a bZIP transcription factor capable of binding to the ABRE2 motif in the maize Cat1 promoter, is induced by ABA, H2O2, drought and salt. Constitutive expression of ABP9 in transgenic Arabidopsis leads to remarkably enhanced tolerance to multiple stresses including drought, high salt, freezing temperature and oxidative stresses. ABP9 expressing Arabidopsis plants also exhibit increased sensitivity to exogenously applied ABA during seed germination, root growth and stomatal closure and improved water-conserving capacity. Moreover, constitutive expression of ABP9 causes reduced cellular levels of ROS, alleviated oxidative damage and reduced cell death, accompanied by elevated expression of many stress/ABA responsive genes including those for scavenging and regulating ROS. Taken together, these results suggest that ABP9 may play a pivotal role in plant tolerance to abiotic stresses by fine tuning ABA signaling and control of ROS accumulation