114 resultados para EAC


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The first generation e-passport standard is proven to be insecure and prone to various attacks. To strengthen, the European Union (EU) has proposed an Extended Access Control (EAC) mechanism for e-passports that intends to provide better security in protecting biometric information of the e-passport bearer. But, our analysis shows, the EU proposal fails to address many security and privacy issues that are paramount in implementing a strong security mechanism. In this paper we propose an on-line authentication mechanism for electronic passports that addresses the weakness in existing implementations, of both The International Civil Aviation Organisation (ICAO) and EU. Our proposal utilises ICAO PKI implementation, thus requiring very little modifications to the existing infrastructure which is already well established.

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Although both the size and chemical composition of ambient particles are important parameters in determining their toxicities, their relative contributions are unclear (Heal et al., 2012). Children are particularly at risk to the detrimental health effects that have been linked to long term exposure to airborne particles (See e.g. Ruckerl et al., 2011). However, there is currently limited understanding of the health effects in children due to long term exposure to airborne particles. Schools are locations within an urban environment where children experience significant exposure to vehicle emissions, and to date there is limited information assessing children’s exposure at school. This study is a part of a large project aimed at gaining a holistic picture of the exposure of children to traffic related pollutants. In the current paper, results from the investigation of the elemental composition of airborne particle at urban schools are presented.

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Barrett's esophagus is an increasingly common disease that is strongly associated with reflux of stomach acid and usually a hiatus hernia, and it strongly predisposes to esophageal adenocarcinoma (EAC), a tumor with a very poor prognosis. We report the first genome-wide association study on Barrett's esophagus, comprising 1,852 UK cases and 5,172 UK controls in the discovery stage and 5,986 cases and 12,825 controls in the replication stage. Variants at two loci were associated with disease risk: chromosome 6p21, rs9257809 (P combined = 4.09 × 10-9; odds ratio (OR) = 1.21, 95% confidence interval (CI) =1.13-1.28), within the major histocompatibility complex locus, and chromosome 16q24, rs9936833 (P combined = 2.74 × 10-10; OR = 1.14, 95% CI = 1.10-1.19), for which the closest protein-coding gene is FOXF1, which is implicated in esophageal development and structure. We found evidence that many common variants of small effect contribute to genetic susceptibility to Barrett's esophagus and that SNP alleles predisposing to obesity also increase risk for Barrett's esophagus. © 2012 Nature America, Inc. All rights reserved.

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Allozyme electrophoresis was used to investigate the genetic stock structure of snapper, Pagrus auratus (Bloch and Schneider) on the east coast of Australia. Spatial variation in allele frequency was examined at nine polymorphic loci. The results support a single, relatively weak genetic disjunction among the P. auratus populations north of Sydney (latitude 33°52?) but south of Forster (latitude 31°58?) on the central coast of New South Wales. There was also evidence for genetic isolation by distance on the east coast. The influence of the East Australian Current (EAC) in transporting larvae to the south, coupled with the general northward migration pattern of adult snapper is believed to be responsible for maintaining a panmictic snapper population on much of the east coast of Australia.

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Studies on the dilute solution properties of methylmethacrylate-acrylonitrile random copolymers of three different compositions, 0.236, 0.5 and 0.74 mole fraction (m.f.) of acrylonitrile (AN) designated as MAa, MAb and MAc, respectively, have been made in good solvents and theta solvents. MAa has been studied in benzene (Bz) and ethylacetate (EAc). MAb in acetonitrile (MeCN), dimethyl sulphoxide (DMSO) and a binary solvent mixture of Bz and dimentyl formamide (DMF) in the volume ratio 6.5:1 designated as BM1 and MAc in MeCN, DMSO and Bz + DMF in the volume ratio 1.667:1 designated as BM2. The Mark-Houwink exponent ‘a’ reveals that Bz is a theta solvent for MAa at 20°C. For MAb and MAc, BM1 and BM2, respectively have ‘a’ values of 0.5 at all three temperatures studied (30°, 40° and 50°C). It is not clear whether they represent theta states or preferential adsorption plays a role complicating the behaviour in solution. The values of A2 are very low in MeCN considering that it is a very good solvent for the copolymer, ‘a’ values for MAb and MAc being 0.75 and 0.7, respectively.

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The following problem is considered. Given the locations of the Central Processing Unit (ar;the terminals which have to communicate with it, to determine the number and locations of the concentrators and to assign the terminals to the concentrators in such a way that the total cost is minimized. There is alao a fixed cost associated with each concentrator. There is ail upper limit to the number of terminals which can be connected to a concentrator. The terminals can be connected directly to the CPU also In this paper it is assumed that the concentrators can bo located anywhere in the area A containing the CPU and the terminals. Then this becomes a multimodal optimization problem. In the proposed algorithm a stochastic automaton is used as a search device to locate the minimum of the multimodal cost function . The proposed algorithm involves the following. The area A containing the CPU and the terminals is divided into an arbitrary number of regions (say K). An approximate value for the number of concentrators is assumed (say m). The optimum number is determined by iteration later The m concentrators can be assigned to the K regions in (mk) ways (m > K) or (km) ways (K>m).(All possible assignments are feasible, i.e. a region can contain 0,1,…, to concentrators). Each possible assignment is assumed to represent a state of the stochastic variable structure automaton. To start with, all the states are assigned equal probabilities. At each stage of the search the automaton visits a state according to the current probability distribution. At each visit the automaton selects a 'point' inside that state with uniform probability. The cost associated with that point is calculated and the average cost of that state is updated. Then the probabilities of all the states are updated. The probabilities are taken to bo inversely proportional to the average cost of the states After a certain number of searches the search probabilities become stationary and the automaton visits a particular state again and again. Then the automaton is said to have converged to that state Then by conducting a local gradient search within that state the exact locations of the concentrators are determined This algorithm was applied to a set of test problems and the results were compared with those given by Cooper's (1964, 1967) EAC algorithm and on the average it was found that the proposed algorithm performs better.

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Objective: The present study was undertaken to evaluate the antitumor and antioxidant status of ethanol extract of Terminalia catappa leaves against Ehrlich ascites carcinoma (EAC) in Swiss albino mice. Materials and Methods: The leaves powder was extracted with Soxhlet apparatus and subjected to hot continuous percolation using ethanol (95% v/v). Tumor bearing animals was treated with 50 and 200 mg/kg of ethanol extract. EAC induced in mice by intraperitoneal injection of EAC cells 1 x 10(6) cells/mice. The study was assed using life span of EAC-bearing hosts, hematological parameters, volume of solid tumor mass and status of antioxidant enzymes such as lipid peroxidation (LPO), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) activities. Total phenolics and flavonoids contents from the leaves extract were also determined. Results: Total phenolics and flavonoids contents from the leaves extract were found 354.02 and 51.67 mg/g extract. Oral administration of ethanol extract of T. catappa (50 and 200 mg/kg) increased the life span (27.82% and 60.59%), increased peritoneal cell count (8.85 +/- 0.20 and 10.37 +/- 0.26) and significantly decreased solid tumor mass (1.16 +/- 0.14 cm(2)) at 200 mg/kg as compared with EAC-tumor bearing mice (P < 0.01). Hematological profile including red blood cell count, white blood cell count, hemoglobin (11.91 +/- 0.47 % g) and protein estimation were found to be nearly normal levels in extract-treated mice compared with tumor bearing control mice. Treatment with T. catappa significantly decreased levels of LPO and GSH, and increased levels of SOD and CAT activity (P < 0.01). Conclusion: T. catappa exhibited antitumor effect by modulating LPO and augmenting antioxidant defense systems in EAC bearing mice. The phenolic and flavonoid components in this extract may be responsible for antitumor activity.

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4-Thiazolidinone derivatives were synthesized using T3P (R)-DMSO media as a cyclodehydrating agent. All the molecules were tested for their cytotoxicity against leukemic cell lines. The compound 3-(4-bromophenyl)-2-(4-(dimethylamino)phenyl)thiazolidin-4-one (4e) with electron donating substituent at para position of phenyl ring displayed considerable cytotoxicity against Reh and Nalm6 cells with an IC50 value of 11.9 and 13.5 mu M, respectively. Furthermore, the compound 4e tested for tumor regression studies induced by EAC in Swiss albino mouse. Both in vitro and in vivo results suggested significant antiproliferative activity of compound 4e in Reh cells and mouse tumor tissue treated with compound 4e showed multifocal areas of necrosis and numerous number of apoptotic cells. (C) 2015 Elsevier Ltd. All rights reserved.

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RFID is a technology that enables the automated capture of observations of uniquely identified physical objects as they move through supply chains. Discovery Services provide links to repositories that have traceability information about specific physical objects. Each supply chain party publishes records to a Discovery Service to create such links and also specifies access control policies to restrict who has visibility of link information, since it is commercially sensitive and could reveal inventory levels, flow patterns, trading relationships, etc. The requirement of being able to share information on a need-to-know basis, e.g. within the specific chain of custody of an individual object, poses a particular challenge for authorization and access control, because in many supply chain situations the information owner might not have sufficient knowledge about all the companies who should be authorized to view the information, because the path taken by an individual physical object only emerges over time, rather than being fully pre-determined at the time of manufacture. This led us to consider novel approaches to delegate trust and to control access to information. This paper presents an assessment of visibility restriction mechanisms for Discovery Services capable of handling emergent object paths. We compare three approaches: enumerated access control (EAC), chain-of-communication tokens (CCT), and chain-of-trust assertions (CTA). A cost model was developed to estimate the additional cost of restricting visibility in a baseline traceability system and the estimates were used to compare the approaches and to discuss the trade-offs. © 2012 IEEE.

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大洋环流是海盆尺度上海水的持久流动,是海洋中质量、热量输运的主要通道,对全球气候变化有重要影响。经过二十年来的大量调查研究,对海洋上层的风生大洋环流有了比较充分的认识。然而,近几十年来的大量观测显示,大洋环流的垂直结构并非像传统认识的那样单一,在很多区域存在与之反向的次表层潜流,如北赤道流(NEC)下方的北赤道逆流(NEUC)、棉兰老海流(MC)下方的棉兰老潜流(MUC),吕宋岛附近黑潮(KC)下方的吕宋潜流(LUC),东澳大利亚海流(EAC)下方的大堡礁潜流(GBRUC)和东澳大利亚潜流(EAUC),阿加勒斯海流(AC)下方的阿加勒斯潜流(AUC)等。这些潜流一般分布在西边界,或者在西边界处增强,称为“西边界潜流(WBUC)”。与表层环流相比,对次表层潜流的结构和形成机制认识不足,因此利用不断更新的各种实测数据和高分辨率同化数据,通过理论分析和数值试验,探讨研究次表层潜流的分布特征和形成机制,对于大洋环流动力学理论的进一步发展具有重要的科学意义。 本文利用中国ARGO资料中心提供的ARGO资料、全球简单海洋资料同化分析系统产生的SODA同化资料和日本地球模拟器模拟出来的OFES资料,分析了北太平洋潜流(NEUC、MUC和LUC)、南太平洋潜流(GBRUC和EAUC)和南印度洋潜流(AUC)的时间和空间分布特征,并基于温跃层以下转向的地转判据分析了其形成机制。主要结果如下: (1)在菲律宾以东海域,表层的NEC在12N附近的西边界分叉,形成向北的KC和向南的MC。在400-800米左右棉兰老岛东侧128E-130E处出现与上层海流方向相反的潜流MUC,MUC在9N和12N附近转向东并分成2支,汇入NEC下方的2支并行向东流的NEUC。到了1000米左右,吕宋岛东侧122E-124E处出现LUC,而MUC也有向岸的趋势,限制在127E以西的范围,两者在12N附近相遇,然后转向东汇入NEUC。随着深度的加深,NEUC的北侧分支流轴向北偏移。从SODA资料和OFES资料在8N、18N和138E断面的气候态年平均和月平均温度剖面可以很清晰的看出,温跃层分别呈现东高西低、西高东低和南高北低的趋势,这与各个断面上表层流和次表层逆流之间等值线倾斜方向一致。从月平均的速度剖面可以看出,MC一般位于600db以上,600db以下出现北向次表层潜流MUC,MUC春夏较强,秋冬较弱;KC一般位于500db以上,个别月份深入到2000db,其下方均有南向的LUC出现,LUC春夏较弱,秋冬较强;上层西向NEC的主体一般位于400db以上,其下方均有东向的NEUC出现,NEUC春夏较强,秋冬较弱。 在北太平洋菲律宾以东海域,同时满足两个判据的区域与潜流的发生区域符合情况较好,唯一的不同在于LUC汇入NEUC的区域没有同时满足两个判据。这是由于在吕宋岛和棉兰老岛东侧,海底地形较为陡峭,海流情况较为清晰,沿岸涡较少,而且在此区域内温跃层较浅,这些都为形成温跃层以下的地转流反向提供了充分的条件。 (2)在澳大利亚以东海域,表层的南赤道流(SEC)在澳大利亚东岸15S附近分叉,分为向北的北昆士兰海流(NQC)和向南的东澳大利亚海流(EAC)。500m-1000m,23S附近出现一支北向的次表层海流,沿着澳大利亚陆坡经过大堡礁抵达巴布亚新几内亚沿岸转向东,汇入新几内亚沿岸潜流(NGCUC),这支海流就是大堡礁潜流(GBRUC)。1000m-2000m,SEC下方15S附近出现东向的逆流。在2000m以下,由于地形的影响,海流局限在几个不连续的部分,而且流型较乱。从SODA资料和OFES资料在18S和30S断面的气候态年平均和月平均温度剖面可以很清晰的看出,温跃层均呈现西高东低的趋势。在18S,南向的EAC一般位于400db以上,其下方均有持续的GBRUC出现,一般有两个中心,春夏季较强,秋冬季较弱。在30S断面,EAC一般存在于2000db以上,其下方的次表层流并不规则。从此海域的气候态月平均分布来看,在大多月份没有北向的逆流存在,这说明其下方的次表层逆流并不是一个常年存在的现象。 在南太平洋,同时满足两个判据的区域包括SEC下方逆流的发生区域和澳大利亚东岸的沿岸区域,这些区域部分与潜流的发生区域符合较好,只是在30S左右并没有发生潜流的区域也同时满足判据。这是由于在30S附近,温跃层较深,导致了地转流较深,同时此区域内海底地形变化比较大,虽然在此位置形成了逆向的地转流,但是因为地形的限制,在此区域内不能形成有体系的逆流。 (3)在西南印度洋,SEC在非洲东岸分叉,形成一支源于25S的西南向海流——AC,这支海流平均流速达90cm/s左右,最大速度超过140cm/s。在其下方2000m左右,从35S开始在岸边出现东北向逆流——AUC,速度较小,仅为2cm/s左右。从31S、33S和35S断面的气候态年平均温度断面可以很清晰的看出,温跃层明显呈现西高东低的趋势。从月平均经向流速断面可以看出,在各个月份AC下方均出现不同强度的AUC,AC和AUC之间的等值线倾斜方向与温跃层的倾斜方向一致。 在南印度洋,满足判据的区域包括南非沿岸AUC的发生区域和南非东南的部分海域,南非沿岸的AUC紧靠岸边且深度较深,这是因为此区域内温跃层较深,导致形成的地转流位置较深,而形成的逆流由于与海底的摩擦而大大削弱。南非东南部分海域满足判据,大概是由于此区域海流比较复杂,而且此海域多涡。 表面风应力的强迫以及风生环流的斜压调整,使得潜流所在海域的海平面高度和温跃层倾斜方向相反,热带流涡和副热带流涡西向强化加强了该海域温跃层的倾斜程度,从而导致了次表层地转流反向。因此,大洋中次表层潜流是大洋斜压风生环流不可缺少的重要部分。但是在不同的海域存在不同的地形分布和海流分布,所以此理论只在某些合适的区域得到很好的体现。

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Social psychologists have long been interested in understanding the conditions under which attitudes influence behaviors, and they have formed two relatively independent theoretical perspectives in the attitude-behavior domain. One perspective, which we adopt in the present paper, focuses on investigating the effect of attitude strength on the attitude-behavior relationship. Specifically, the present research investigates the role of structural consistency, a dimension of attitude strength, on the attitude-behavior relationship. Structural consistency has typically been defined as the extent to which one aspect of individual’s attitude is consistent with either his or her overall attitude toward the object or the other aspect of the attitude, including affective-cognitive consistency (ACC), evaluative-cognitive consistency (ECC) and evaluative-affective consistency (EAC). The ECC and EAC can be integrated into the attitude base. Despite the evidence that structural consistency is associated with attitude-behavior relationship, there are some limitations in previous studies: (1) attitude base and ACC have been rarely studied together ;( 2) researchers often used the term behavior in a broad sense to encompass behavioral intentions as well as actual behaviors ;( 3) the effects were all investigated at individual level. The present research tried to explore the effects of ACC and attitude base on attitude-behavioral intention-actual behavior relationships at individual and group levels in different behavior areas including shopping, supportive behavior towards officials, and offensive behavior towards governors and central and local governments. The roles of affective and cognitive components of attitudes on general attitudes and following behaviors were also examined in this research. The results indicated that: A. At individual and group levels, the effect of structural consistency on attitude –intention relation is as the same as its effect on attitude-behavior relation, but it varies in different areas. On the other hand, the effect of structural consistency on explicit attitude-behavior relation is different from its effect on implicit attitude-behavior relation. B. The cognitive components of the individuals and groups’ implicit attitudes towards officials, the implicit and explicit attitudes towards governors, and the public’s attitudes towards central and local governments exert the stronger influence on general attitudes. Similarly, the cognitive components also exert the stronger influence on groups’ supportive behaviors towards officials and offensive behaviors towards governors and governments. C. Both group attitude and emotion can influence the group offensive behavior towards governors. The group attitude exerts its influence through the mediating effects of behavior intention and group emotion. The group emotion which is the core factor can exert the direct influence on group offensive behavior towards governors. D. At individual and group levels, the implicit and explicit measures should be used together to collect the attitude data, because the implicit and explicit attitudes can both predict behaviors under most conditions. It is the best implicit attitude measure to use the experts’ evaluations of listed words. And the emotion should be measured by the experts’ evaluations of listed words if the emotion data is used to predict the following behavior.

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Objectives: To determine whether diagnostic triage by general practitioners (GPs) or rheumatology nurses (RNs) can improve the positive predictive value of referrals to early arthritis clinics (EACs).

Methods: Four GPs and two RNs were trained in the assessment of early in?ammatory arthritis (IA) by four visits to an EAC supervised by hospital rheumatologists. Patients referred to one of three EACs were recruited for study and assessed independently by a GP, an RN and one of six rheumatologists. Each assessor was asked to record their clinical ?ndings and whether they considered the patient to have IA. Each was then asked to judge the appropriateness of the referral according to predetermined guidelines. The rheumatologists had been shown previously to have a satisfactory level of agreement in the assessment of IA.

Results: Ninety-six patients were approached and all consented to take part in the study. In 49 cases (51%), the rheumatologist judged that the patient had IA and that the referral was appropriate. The assessments of GPs and RNs were compared with those of the rheumatologists. Levels of agreement were measured using the kappa value, where 1.0 represents total unanimity. The kappa value was
0.77 for the GPs when compared with the rheumatologists and 0.79 for the RNs. Signi?cant stiffness in the morning or after rest and objective joint swelling were the most important clinical features enabling the GPs and RNs to discriminate between IA and non-IA conditions.

Conclusion: Diagnostic triage by GPs or RNs improved the positive predictive value of referrals to an EAC with a degree of accuracy approaching that of a group of experienced rheumatologists.

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BACKGROUND & AIMS: Insulin-like growth factor (IGF) axis plays a key role in cell development, proliferation, and survival and is implicated in the etiology of several cancers. Few studies have examined the relationship between genetic variation of this axis and esophageal adenocarcinoma (EAC) or its precursors. METHODS: In a population-based case-control study, we investigated the association of common polymorphisms of IGF-1, IGF-2, IGF-1 receptor, IGF binding protein -3, growth hormones (GH) 1 and GH2, and GH receptor with reflux esophagitis (RE), Barrett esophagus (BE), and EAC. Two hundred and thirty RE, 224 BE, 227 EAC cases, and 260 controls were studied. Gene polymorphisms were identified using publicly available online resources; 102 IGF axis tag and putatively functional single-nucleotide polymorphisms (SNPs) were analyzed using MassARRAY iPLEX and Taqman assays. Results were analyzed using Haploview.
RESULTS: Three polymorphisms were disease-associated. IGF1 SNP rs6214 was associated with BE (adjusted P = .039). Using GG genotype as reference, odds ratio for BE in AA (wild-type) was 0.43 (95% confidence interval [CI], 0.24-0.75). GH receptor SNP rs6898743 was associated with EAC (adjusted P = .0112). With GG as reference, odds ratio for EAC in CC (wildtype) genotype was 0.42 (95% CI, 0.23-0.76). IGF1 (CA)(17) 185-bp allele was associated with RE (adjusted P = .0116). Using IGF1(non17) as reference, odds ratio for RE in IGF1(17) carriers was 7.29 (95% CI, 1.57-46.7).
CONCLUSIONS: In this study, 3 polymorphisms of IGF genes were associated with EAC or its precursors. These polymorphisms may be markers of disease risk; independent validation of our findings is required. These results suggest the IGF pathway is involved in EAC development.