Symbolic links in the Open Directory Project

We present a study to develop an improved understanding of symbolic links in web directories. A symbolic link is a hyperlink which makes a directed connection from a webpage along one path through a directory to a page along another path. While symbolic links are ubiquitous in web directories such as Yahoo!, they are under-studied and, as a result, their uses are poorly understood. A cursory analysis of symbolic links reveals multiple uses: to provide navigational shortcuts deeper into a directory, backlinks to more general categories, and multiclassification. We investigated these uses in the Open Directory Project (ODP), the largest, most comprehensive, and most widely distributed human-compiled taxonomy of links to websites, which makes extensive use of symbolic links. The results reveal that while symbolic links in ODP are used primarily for multiclassification, only few multiclassification links actually span top- and second-level categories. This indicates that most symbolic links in ODP are used to create multiclassification between topics which are nested more than two levels deep and suggests that there may be multiple uses of multiclassification links. We also situate symbolic links vis à vis other semantic and structural link types from hypermedia. We anticipate that the results and relationships identified and discussed in this paper will provide a foundation for (1) users for understanding the usages of symbolic links in a directory, (2) designers to employ symbolic links more effectively when building and maintaining directories and for crafting user interfaces to them, and (3) information retrieval researchers for further study of symbolic links in web directories.     

Enantioselective assembly of multi-layer 3D chirality

The first enantioselective assembly of sandwich-shaped organo molecules has been achieved by conducting dual asymmetric Suzuki-Miyaura couplings and nine other reactions. This work also presents the first fully C-C anchored multi-layer 3D chirality with optically pure enantiomers. As confirmed by X-ray diffraction analysis that this chiral framework is featured by a unique C₂-symmetry in which a nearly parallel fashion consisting of three layers: top, middle and bottom aromatic rings. Unlike the documented planar or axial chirality, the present chirality shows its top and bottom layers restrict each other from free rotation, i.e., this multi-layer 3D chirality would not exist if either top or bottom layer is removed. Nearly all multi-layered compounds showed strong luminescence of different colors under UV irradiation, and several randomly selected samples displayed aggregation-induced emission (AIE) properties. This work is believed to have broad impacts on chemical, medicinal and material sciences including optoelectronic materials in future.     

Influence of human behavior and the principle of least effort on library and information science research

This study identified the influence of the main concepts contained in Zipf's classic 1949 book entitled Human Behavior and the Principle of Least Effort (HBPLE) on library and information science (LIS) research. The study analyzed LIS articles published between 1949 and 2013 that cited HBPLE. The results showed that HBPLE has a growing influence on LIS research. Of the 17 cited concepts that were identified, the concept of “Zipf's law” was cited most (64.8%), followed by “the principle of least effort” (24.5%). Although the concept of “the principle of least effort,” the focus of HBPLE, was not most frequently observed, an increasing trend was evident regarding the influence of this concept. The concept of “the principle of least effort” has been cited mainly by researchers of information behavior and served to support the citing authors’ claims. By contrast, the concept of “Zipf's law” received the most attention from bibliometrics research and was used mainly for comparisons with other informetrics laws or research results.     

Measuring the temporal dynamics of policy mixes – An empirical analysis of renewable energy policy mixes’ balance and design features in nine countries

Complex societal or environmental problems require fast and substantial socio-technical transitions. For instance, in the case of climate change, these transitions need to take place in the energy, transport and several industry sectors. To induce and accelerate such transitions, numerous policy interventions are required, which interact with each other in policy mixes. While several conceptual studies on policy mixes have been published recently, there is very little empirical research apart from single case or small-n studies. It has been prominently argued that the debate about policy mixes has reached an impasse partly due to this lack of empirical work. This paper addresses this gap by providing a first analysis of the temporal dynamics of complex policy mixes. To do so, we develop a conceptualization and measurement of policy mix balance across instrument types as well as policy mix design features (in the form of intensity as a general and technology specificity as a technology-focused design feature). This allows us to answer the question how temporal dynamics of policy mixes differ between countries regarding their balance and design features. Our measurement approach is developed bottom-up, i.e., policies are assessed individually and then aggregated systematically at the policy mix level. This enables overcoming the ‘dependent variable problem in the study of policy change’, i.e., the problem of measuring policy output. More specifically, we develop a comparative dataset of 522 renewable energy policies in nine OECD countries. Our analysis shows that countries’ policy mix dynamics vary strongly regarding some variables (e.g., technology specificity) but less regarding others (e.g., balance). As a validity check, we also test the effects of these mix dynamics on policy outcome in the form of renewable energy technology diffusion. We reflect our findings in light of the theoretical debates around policy mixes and policy design and discuss how our results provoke an agenda for the new generation of research on policy mixes. We specifically discuss avenues for future research with a particular focus on the ‘politics of policy mixes’.     

Liberation of public data: Exploring central themes in open government data and freedom of information research

This paper conducts a comparative literature survey of Open Government Data (OGD) and Freedom of Information (FOI), with a view to tracking the central themes in the two civil society campaigns. With seeming similarities and a growing popularity in research, the major themes framing research on the two movements have not clearly emerged. Topic modelling, text mining and document analysis methods are used to extract the themes as well as key named entities. The topics are subsequently labeled and with expert guidance, their semantic meaning are provided. The results indicate that the major theme in FOI research borders on issues relating to disclosure, publishing, access and cost of requests. On the other hand, themes in OGD research have largely centered on technology and related concepts. The approach also helped in determining key similarities and differences in the two campaigns as reported in research.     

“中欧班列”运输组织策略研究

基础设施互联互通是"一带一路"建设的优先领域。"中欧班列"是欧亚大陆货物运输新的渠道和基础设施"互通"的重要举措,已成为"一带一路"建设的标志性运输合作平台。文章在阐释"中欧班列"运营的战略意义和存在问题后,提出如何正确认识这种新的运输方式,指出"中欧班列"在我国对外贸易运输中的地位与作用有限,只适用于远离东部沿海港口的中西部地区以及国际大通道沿线地区,且在合理的地域范围内运输适宜的货物,才能盈利。最后,作者提出构建轴-辐组织模式,打造关键货物集散枢纽,统筹规范组织"中欧班列",以降低"中欧班列"的运输成本,从而产生规模经济。     

Relations between the shape of a size-frequency distribution and the shape of a rank-frequency distribution

We study the dependence of the shape of the rank-frequency distribution g on the shape of the size-frequency distribution f and vice versa. We show mathematically that g is convexly decreasing if and only if f is monotonically decreasing and that g has an S-shape (i.e., g is first convexly decreasing and then concavely decreasing) if and only if f is first increasing and then decreasing.     

Measuring the success of the Greek Taxation Information System

The transformation of many governments all around the world into new forms, namely, electronic government (e-Government), could not leave the Greek government unaffected. Therefore, it initiated an e-Government project related to national information systems and finance services, the Greek Taxation Information System (TAXIS). The purpose of this paper is to investigate the success of TAXIS from the perspective of expert employees, who work in public taxation agencies. This topic is interesting, because TAXIS is applied in a tax-driven country, under a mandatory setting. Also, it is the first time that the success of this project is examined, from the perspective of employees, using IS success models. The study adapts DeLone and McLean [DeLone, W. H., & McLean, E. R. (2003). The DeLone and McLean model of information systems success: A ten year update. Journal of Management Information Systems, 19(4), 9–30] and Seddon's [Seddon, P. B. (1997). A respecification and extension of the DeLone and McLean model of IS success. Information Systems Research, 8(3) 240–253] information systems success models. The model developed includes the constructs of information, system and service quality, perceived usefulness and user satisfaction. The results provide evidence that there are strong connections between the five success constructs. All hypothesized relationships are supported, except for the relationship between system quality and user satisfaction. The empirical evidence and discussion presented can help the Greek Government improve and fully exploit the potential of TAXIS as an innovative tool for taxation purposes.     

2021年中国经济增长速度的预测分析与政策建议

2021年中国面临着新冠肺炎疫情和复杂国际形势的共同影响,未来经济发展方向备受关注。文章依据经济理论、现实经验、生产要素变化等,系统分析和预测了中国中长期经济增长速度的变动趋势为呈波浪形下降。基于投入产出技术、计量经济学、景气分析法、专家分析法、情景分析等,提出了年度GDP增速预测的系统综合因素预测法。在对2020年中国全年经济发展进行简要回顾的基础上,根据目前国内、国际形势对2021年中国经济增长速度做出了预测:预计2021年中国经济将实现恢复性增长,全年增速为8.5%左右。文章进而基于经济形势分析提出了促进中国经济发展的相关政策建议:继续促进消费,稳增长、促发展,建设科技创新型国家,加快产业结构转型升级。     

Human capital intensity in technology-based firms located in Portugal: Does foreign ownership matter?

This paper contributes to the scarce empirical literature on the impact of foreign ownership on human capital intensity. New evidence is provided, based on a comprehensive, large-scale survey of technology-based firms located in Portugal. The key findings are that: (1) foreign ownership directly (and significantly) impacts a firm's general human capital (education); (2) foreign ownership indirectly (and significantly) impacts a firm's specific human capital (skills); (3) the total impact of foreign ownership on a firm's human capital intensity is higher for education- (general) than for skills- (specific) related human capital intensity. Giving the critical importance of both FDI and human capital development for an ‘intermediate’ economy like Portugal (lagging behind in terms of human capital stock, and seeming to have lost part of its attractiveness as an FDI location), the paper discusses related policy implications. It is believed that our results and conclusions may be useful for other countries facing similar challenges.     

A dynamic output feedback control law for elastic joint robots via feedback-passivity approach

Motivated by recent dynamic output feedback passivation results, a new set-point control law is presented for an elastic joint robot when the velocity measurements are not available. The proposed methodology designs an additional dynamics with which the parallel-connected system is feedback passive. That is, the composite nonlinear robot system has relative degree one with a new output and its zero-dynamics subsystem becomes the virtual closed-loop system with a simple proportional-derivative (PD) control law. This approach provides an alternative way of replacing the role of the velocity measurements for the PD law. With the proposed control law, the transfer function of the additional system has the form of sG(s) with a strictly positive real (SPR) G(s). Robustness analysis is also given with regard to uncertainties on the robot parameters. The performance of the proposed control law is illustrated in the simulation studies of a manipulator with three revolute elastic joints.     

Biological and Biochemical Potential of Sea Snake Venom and Characterization of Phospholipase A<Subscript>2</Subscript> and Anticoagulation Activity

This study is designed to isolate and purify a novel anti-clotting protein component from the venom of Enhydrina schistosa, and explore its biochemical and biological activities. The active protein was purified from the venom of E. schistosa by ion-exchange chromatography using DEAE-cellulose. The venom protein was tested by various parameters such as, proteolytic, haemolytic, phospholipase and anti-coagulant activities. 80 % purity was obtained in the final stage of purification and the purity level of venom was revealed as a single protein band of about 44 kDa in SDS-polyacrylamide electrophoresis under reducing conditions. The results showed that the Potent hemolytic activity was observed against cow, goat, chicken and human (A, B and O positive) erythrocytes. Furthermore, the clotting assays showed that the venom of E. schistosa significantly prolonged in activated partial thromboplastin time, thrombin time, and prothrombin time. Venomous enzymes which hydrolyzed casein and gelatin substrate were found in this venom protein. Gelatinolytic activity was optimal at pH 5–9 and ¹H NMR analysis of purified venom was the base line information for the structural determination. These results suggested that the E. schistosa venom holds good promise for the development of novel lead compounds for pharmacological applications in near future.     

FABP2 gene polymorphism and metabolic syndrome in elderly people of croatian descent

Introduction:

Metabolic syndrome (MetS) is a multifactorial disorder in which dyslipidemia plays an important role. Fatty acid-binding protein 2 (FABP 2) is responsible for transport of free fatty acids in the intestinal endothelium cells. FABP2-genetic variants might affect plasma lipid concentrations and intracellular lipid transport. The aim of this study was to investigate the association between FABP2 Ala54Thr genetic polymorphism and metabolic syndrome and some biochemical and anthropological parameters in elderly subjects.

Materials and methods:

This cross-sectional study included 140 men and 176 women older than 70 years. Fasting serum concentration of glucose, lipid parameters, total proteins and C-reactive protein were determined by standardized methods. Presence (MetS(+)) or absence (MetS(−)) of MetS was determined according to criteria of the International Diabetes Federation. FABP2 genetic polymorphism Ala54Thr (rs1799883) was genotyped with PCR-RFPL.

Results:

The genotype frequencies for Ala/Ala, Ala/Thr and Thr/Thr genotype were 60, 36 and 6 in MetS(−), and 131, 70 and 13 in MetS(+), respectively, without statistical significance (P = 0.567). Ala/Ala genotype was a subgroup of non-carriers, while Ala/Thr and Thr/Thr genotypes were Thr54-carriers. Median triglyceride concentration was significantly lower in carriers then in non-carriers for whole MetS(+) group (P = 0.050); there were no significant difference between men with MetS (P = 0.144), but there was a difference between women with MetS (P = 0.020). T-test showed that mean HDL cholesterol concentrations in MetS(+) group for Thr54-carriers was significantly higher in whole group (P = 0.001), and for both genders (men P = 0.039; women P = 0.004) as compared to non-carriers.

Conclusions:

FABP2 genetic polymorphism is associated with lower triglyceride and higher HDL-cholesterol concentrations in elderly subjects with MetS. This genetic variation might be a useful marker for understanding dyslipidemia in MetS.     

2022年中国经济增长速度的预测分析与政策建议

2021年在复杂严峻的国内外环境下,中国政府采取多项措施,科学统筹疫情防控和经济社会发展,经济恢复持续增长。2022年,中国经济发展面临着很大的不确定性。文章系统分析和预测了中国中长期经济增长速度的发展趋势和变化规律,预计中国中长期经济增速将呈波浪形下降趋势。基于投入产出技术、计量经济学、景气分析法、专家分析法、情景分析等,为预测国内生产总值(GDP)构建了系统综合因素预测法。在对2021年中国全年经济发展进行回顾和分析的基础上,根据当前国内、国际形势对2022年中国经济增长速度作出了预测:预计2022年中国经济增长态势将基本恢复正常,全年增速为5.5%左右。文章基于经济形势分析提出了相关政策建议:科学有序防疫,加大宏观政策跨周期调节,进一步提振消费,科学灵活实现"双碳"目标,加快发展数字经济和产业数字化。     

First genome sequence of Chilean Brucella canis SCL strain provides insights on the epidemiology and virulence factors,explaining differences between geographical origins

BackgroundBrucella canis is the etiological agent of canine brucellosis, a worldwide neglected zoonosis that constitutes one of the major infectious causes of infertility and reproductive failure in dogs. Although genomic information available for this pathogen has increased in recent years, here we report the first genome sequencing of a B. canis strain in Chile, and the differences in virulence genes with other B. canis strains.ResultsGenome assembly produced a total length of 3,289,216 bp, N50 of 95,163 and GC% of 57.27, organized in 54 contigs in chromosome I, and 21 contigs in chromosome II. The genome annotation identified a total of 1981 CDS, 3 rRNA and 36 tRNA in chromosome I, and 1113 CDS and 10 tRNA in chromosome II. There is little variation between the different strains and the SCL isolate. Phylogenetic analysis showed that the Chilean SCL strain is closely related to B. canis and B. suis strains. Small differences were found when compared to the Serbian isolate, but all strains shared the same recent common ancestor. Finally, changes in the sequence of some virulence factors showed that the SCL strain is similar to other South American B. canis strains.ConclusionsThis work sequenced and characterized the complete genome of B. canis strain SCL, evidencing the complete presence of all the genes of the virB operon, and minor changes in outer membrane proteins and in the urease operon. Our data suggest that B. canis was introduced from North America and then spread throughout the South American continent.How to cite: Borie C, Bravo C, Dettleff P, et al. First genome sequence of Chilean Brucella canis SCL strain provides insights on the epidemiology and virulence factors, explaining differences between geographical origins Electron J Biotechnol 2021;49. https://dx.doi.org/10.1016/j.ejbt.2020.10.002.     

An application of homomorphic deconvolution to the tomographic restoration of radiographs

This paper derives an optimal homomorphic tomographic filter, to restore tomographic images of blurred radiographs, by taking into account the noise contributed by the other layers. The method is based on the homomorphic deconvolution technique, which is well-known for its performance in image restoration. A computer simulation of the procedure is presented. The results are compared with those obtained by using inverse filtering (3, IEEE Trans on Medical Imaging, Vol. 2, pp. 89–102, 1983) and Wiener filtering (4, Proc. Digitech '84). The paper shows that homomorphic filtering is a suitable and often preferable technique for the tomographic filtering of radiographs.