2,696 research outputs found
Dr. Yang Zhong: an explorer on the road forever
On the morning of September 25th 2017, grievous news spread from the remote Ordos region of Inner Mongolia to Fudan University campus in Shanghai. Professor Yang Zhong, a famous botanist and the Dean of Fudan University’s graduate school, passed away in a tragic car accident while on a business trip
Phase transition in spin systems with various types of fluctuations
Various types ordering processes in systems with large fluctuation are overviewed. Generally, the so-called order–disorder phase transition takes place in competition between the interaction causing the system be ordered and the entropy causing a random disturbance. Nature of the phase transition strongly depends on the type of fluctuation which is determined by the structure of the order parameter of the system. As to the critical property of phase transitions, the concept “universality of the critical phenomena” is well established. However, we still find variety of features of ordering processes. In this article, we study effects of various mechanisms which bring large fluctuation in the system, e.g., continuous symmetry of the spin in low dimensions, contradictions among interactions (frustration), randomness of the lattice, quantum fluctuations, and a long range interaction in off-lattice systems
Strategic Learning for Active, Adaptive, and Autonomous Cyber Defense
The increasing instances of advanced attacks call for a new defense paradigm
that is active, autonomous, and adaptive, named as the \texttt{`3A'} defense
paradigm. This chapter introduces three defense schemes that actively interact
with attackers to increase the attack cost and gather threat information, i.e.,
defensive deception for detection and counter-deception, feedback-driven Moving
Target Defense (MTD), and adaptive honeypot engagement. Due to the cyber
deception, external noise, and the absent knowledge of the other players'
behaviors and goals, these schemes possess three progressive levels of
information restrictions, i.e., from the parameter uncertainty, the payoff
uncertainty, to the environmental uncertainty. To estimate the unknown and
reduce uncertainty, we adopt three different strategic learning schemes that
fit the associated information restrictions. All three learning schemes share
the same feedback structure of sensation, estimation, and actions so that the
most rewarding policies get reinforced and converge to the optimal ones in
autonomous and adaptive fashions. This work aims to shed lights on proactive
defense strategies, lay a solid foundation for strategic learning under
incomplete information, and quantify the tradeoff between the security and
costs.Comment: arXiv admin note: text overlap with arXiv:1906.1218
Seroprevalence of 13 common pathogens in a rapidly growing U.S. minority population: Mexican Americans from San Antonio, TX
<p>Abstract</p> <p>Background</p> <p>Infection risks vary among individuals and between populations. Here we present information on the seroprevalence of 13 common infectious agents in a San Antonio-based sample of Mexican Americans. Mexican Americans represent the largest and most rapidly growing minority population in the U.S., and they are also considered a health disparities population.</p> <p>Methods</p> <p>We analyzed 1227 individuals for antibody titer to <it>Chlamydophila pneumoniae, Helicobacter pylori, Toxoplasma gondii</it>, cytomegalovirus, Epstein-Barr virus, herpes simplex virus-1, herpes simplex virus-2 (HSV-2), human herpesvirus-6 (HHV-6), varicella zoster virus (VZV), adenovirus-36, hepatitis A virus, and influenza A and B. Seroprevalence was examined as a function of sex, age, household income, and education.</p> <p>Results</p> <p>Seroprevalence estimates ranged from 9% for <it>T. gondii</it> to 92% for VZV, and were similar in both sexes except for HSV-2, which was more prevalent in women. Many pathogens exhibited a significant seroprevalence change over the examined age range (15-94 years), with 7 pathogens increasing and HHV-6 decreasing with age. Socioeconomic status significantly correlated with serostatus for some pathogens.</p> <p>Conclusions</p> <p>Our findings demonstrate substantial seroprevalence rates of these common infections in this sample of Mexican Americans from San Antonio, Texas that suffers from high rates of chronic diseases including obesity and type-2 diabetes.</p
Mean Interplanetary Magnetic Field Measurement Using the ARGO-YBJ Experiment
The sun blocks cosmic ray particles from outside the solar system, forming a
detectable shadow in the sky map of cosmic rays detected by the ARGO-YBJ
experiment in Tibet. Because the cosmic ray particles are positive charged, the
magnetic field between the sun and the earth deflects them from straight
trajectories and results in a shift of the shadow from the true location of the
sun. Here we show that the shift measures the intensity of the field which is
transported by the solar wind from the sun to the earth.Comment: 6 papges,3 figure
Characterizing genetic intra-tumor heterogeneity across 2,658 human cancer genomes.
Intra-tumor heterogeneity (ITH) is a mechanism of therapeutic resistance and therefore an important clinical challenge. However, the extent, origin, and drivers of ITH across cancer types are poorly understood. To address this, we extensively characterize ITH across whole-genome sequences of 2,658 cancer samples spanning 38 cancer types. Nearly all informative samples (95.1%) contain evidence of distinct subclonal expansions with frequent branching relationships between subclones. We observe positive selection of subclonal driver mutations across most cancer types and identify cancer type-specific subclonal patterns of driver gene mutations, fusions, structural variants, and copy number alterations as well as dynamic changes in mutational processes between subclonal expansions. Our results underline the importance of ITH and its drivers in tumor evolution and provide a pan-cancer resource of comprehensively annotated subclonal events from whole-genome sequencing data
The effect of the state sector on wage inequality in urban China: 1988–2007
This paper examines the effect of the public sector and state-owned enterprises (SOEs) on wage inequality in urban China using China Household Income Project data. It applies quantile regression analysis, the Machado and Mata decomposition to investigate how urban wage inequality was affected by the changes in wage structure and employment shares of the public sector and SOEs. We find that since the radical state sector reforms designed to reduce overstaffing and improve efficiency in the late 1990s, urban wage gaps were narrowed due to the reduction in the employment share of the state sector; the wage premium of the state sector in comparison with the non-state sector increased significantly; and changes in the wage structure of the labour market caused the rise in urban wage inequality
Subnational home market bias in Vietnam: Evidence from enterprise‐level data
This paper contributes to the home (market) bias literature where administrative or political borders limit trade across borders. Home bias is well documented at the national and subnational level. To sort out macro (e.g., location characteristics) and micro (e.g., enterprise characteristics) factors behind home bias, we use small and medium‐sized enterprise (SME) data from Vietnam. Using the fractional multinomial logit model, we find that the proportion of SME sales outside of their home markets is positively associated with enterprise size, age, number of business association memberships and the distance of SMEs\u27 most important supplier. In contrast, the proportion of SME sales to neighbouring provinces is negatively associated with the share of SME production for final consumption. Besides enterprise‐level frictions, market characteristics matter too. The proportion of SME sales to customers in their home markets is negatively associated with home or neighbouring provinces\u27 governance quality, while the proportion of sales to customers in neighbouring provinces is positively associated with these areas\u27 governance quality. These suggest that good governance frees SME resources for use in selling to less familiar markets
Measurement of the cross-section and charge asymmetry of bosons produced in proton-proton collisions at TeV with the ATLAS detector
This paper presents measurements of the and cross-sections and the associated charge asymmetry as a
function of the absolute pseudorapidity of the decay muon. The data were
collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with
the ATLAS experiment at the LHC and correspond to a total integrated luminosity
of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements
varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the
1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured
with an uncertainty between 0.002 and 0.003. The results are compared with
predictions based on next-to-next-to-leading-order calculations with various
parton distribution functions and have the sensitivity to discriminate between
them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables,
submitted to EPJC. All figures including auxiliary figures are available at
https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13
Effect of gender preference on fertility: cross-sectional study among women of Tharu community from rural area of eastern region of Nepal
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