An interpretation of the effort function through the mathematical formalism of Exponential Informetric Process

Statistical distributions in the production or utilization of information are most often studied in the framework of Lotkaian informetrics. In this article, we show that an Information Production Process (IPP), traditionally characterized by Lotkaian distributions, can be fruitfully studied using the effort function, a concept introduced in an earlier article to define an Exponential Informetric Process. We thus propose replacing the concept of Lotkaian distribution by the logarithmic effort function. In particular, we show that an effort function defines an Exponential Informetric Process if its asymptotic behavior is equivalent to the logarithmic function β · Log(x) with β > 1, which is the effort function of a Lotkaian distribution.     

From planning to mature: On the success of open source projects

Open source is an example of user-centric innovation initiated by an individual or group of users to satisfy their specific needs; the more a software evolves towards a stable release able to address the requirements of its developers, the more successful the project. In this paper we use a large data-set obtained from SourceForge.net to estimate the relationship between a series of different characteristics of OS projects and the probability of evolution of the source code from a preliminary release to a mature version. We show that while projects distributed under highly restrictive licensing terms (GPL) have a significantly smaller probability of reaching a stable release, applications towards sophisticated users have a larger probability of evolving in the development status. Interestingly, we find that the size of the “community of developers” increases the chances of progress but this effect decreases as the community gets larger, a signal of possible coordination problems.     

Study of the rank- and size-frequency functions in the case of power law growth of sources and items and proof of Heaps’ law

Supposing that the number of sources and the number of items in sources grow in time according to power laws, we present explicit formulae for the size- and rank-frequency functions in such systems. Size-frequency functions can decrease or increase while rank-frequency functions only decrease. The latter can be convex, concave, S-shaped (first convex, then concave) or reverse S-shaped (first concave, then convex). We also prove that, in such systems, Heaps’ law on the relation between the number of sources and items is valid.     

How does health information seeking from different online sources trigger cyberchondria? The roles of online information overload and information trust

Cyberchondria is conceptualized as excessive online searches for medical information, which is typically accompanied by feelings of emotional distress or anxiety. While previous studies in this nascent area have identified various psychological predictors of cyberchondria, a relative dearth of research has explored the role of different online information sources in its development. Informed by the stimulus-organism-response (SOR) model and the literature on cyberchondria, this study proposes a theoretical framework to explain why people develop cyberchondria when seeking medical information via different online sources. Based on a three-wave panel survey (N = 654), our findings suggest that health information seeking via online search engines increases online information overload (β = 0.11, p = .02), while health information seeking via social media platforms and health-specific websites increases online information trust (β = 0.13, p = .005; β = 0.25, p < .001). Additionally, online information overload is negatively related to online information trust (β = -0.39, p < .001). Subsequently, both online information overload and online information trust trigger cyberchondria (β = 0.73, p < .001; β = 0.15, p < .001). This study can contribute to the literature by expanding and deepening our understanding of cyberchondria developmental trajectory as well as emphasizing the pivotal role of online information sources in this complicated and dynamic process.     

The researcher in Italy: A profession in search of recognition

This article deals with the “teething, problems” of the profession of researchers in Italy.This group of professionals in fact has grown very rapidly over the last two decades, but they still seem to be striving to find their proper place in the organization they work in and recognition from society in general. At the same time they have acquired a sufficiently self-awareness as an emerging group and started claiming their own “rights”.The article examines some problems researchers encounter in their specific working setting (industry, university, public research agencies), such as mobility, status, and career prospects.Mobility within the Italian science and technology (S&T) system is very low and is essentially one way, from industry. the professions, and public research agencies, to university, This peculiarity is very closely linked to the high prestige enjoyed by university professors in this country. Moreover. recent laws concerning university teaching staff havede facto saturated the permanent staff, severely restricting both mobility to university and the intake of new blood.An indication of the self-awareness of the profession may he found in the mobilisation of researchers in public research agencies and their claim to their “ecological niche”.It is concluded that researchers, who may he considered a substantially homogeneous group, feel mature and numerous enough to demand the slalus and prestige adequate to their contribution to a modern society; it is also asserted that the delay in granting recognition is due to the organizations and institutions.     

Knowledge translation and research careers: Mode I and Mode II activity among health researchers

Defining knowledge translation activities using Gibbons and Nowotny's Mode I and II forms of knowledge production, health researcher (N = 240) characteristics are compared with their knowledge translation activities. Applied researchers (n = 168) engaged in more Mode II activity (p < .001), perceived their work as having more impact (p < .001), and reported higher levels of relational capital (p < .001) when compared to basic researchers (n = 72). Those from medical schools (n = 128) had more publications (p = .004) as did applied researchers in medical school compared to applied researchers from other faculties (p = .001). These findings provide early empirical insights into emerging tensions in environments where Mode I and Mode II activities co-exist; tensions that may extract unintended costs from researchers. Such costs may be paid in the currency not only of tenure and promotion, but also of successful grant and career scientist award acquisition.     

白皮松后期胚发育的研究

白皮松成熟胚的显著特点是苗端发达，胚苗端的H／D(高度与直径)比率平均为0.83,   有时达0.96，为松柏类植物所罕见。它的苗端可分为四个细胞区：顶端原始细胞、中央母细   胞、周缘组织和肋状分生组织区。在肋状分生组织与下胚轴的髓之间，有一过渡组织区。       从成熟胚的结构来看，松科成熟胚基本上可以分为3种类型：1．子叶特别发达，但下胚轴短; 2．下胚轴与根冠近等长; 3．下胚轴比较发达，白皮松就是这种类型。     

Organizational environment, changing economic conditions, and the effective supervision of technical personnel: A management challenge

Industry's share of R&D funding is increasing while, at the same time, the half-life of technology is decreasing. This condition increases the pressure on technical managers to produce research that is creative and innovative but, at the same time, sensitive to the “bottom line.” Six conditions within the context of the organization play an important role in the management of technical employees: 1) Uncertainty in the work place increases the need for a supportive organizational climate and high information sharing, 2) Compensation appears to produce both functional and dysfunctional consequences for motivation, 3) Engineering personalities have a tendency to favor autonomous, challenging, and meaningful assignments, 4) Organizational structures influence the engineer's ability to process information, 5) The structure of the engineering task has been shown to affect job satisfaction, and 6) Career choices become an important consideration for mature engineers. Each of these issues, if not properly managed, can lead to stress, burnout and eventual employee turnover. Most important however, is the fact that if they are not managed properly, creative output from R&D organizations declines at a time when industry is assuming a greater share of the funding. When creativity declines, a reduction in the number of innovative solutions for products and processes is certain to follow. This condition can lead to serious problems when markets are changing dynamically. This paper reviews research findings related to each of the preceding issues and, discusses the role that each of them plays in the management of engineers and technical personnel. At the end of each discussion we provide some propositions worthy of further research.     

On the generalized Zipf distribution. Part I

This article is concerned with a class of informetric distribution, a family of skew distributions found to describe a wide range of phenomena both within or outside of information sciences and referred to as being of Zipf-type. A generalization of Zipf distribution (a size-frequency form of the Zipf’s law), named the generalized Zipf distribution, is introduced. Two main characterizations of the generalized Zipf distribution are obtained based on the proportionate hazard rate and truncated moments. Finally, some asymptotic properties of the generalized Zipf distribution are investigated.     

电子政务系统建设研究——基于利益相关者理论

回顾梳理现有电子政务系统相关研究,讨论利益相关者理论在电子政务系统建设中的适用性,重点分析了教育电子政务建设项目——家校互动案例,设计并运用战略介入矩阵等利益相关者分析方法研究系统建设中出现的不足,得出电子政务发展至较成熟阶段,系统建设中受众权力不能得到重视、有效参与不足以及缺乏监督等问题是阻碍电子政务系统成功实施的主要原因;以受众为中心、有效参与、完善监督机制是电子政务项目成功实施的关键。     

On test collections for adaptive information retrieval

Traditional Cranfield test collections represent an abstraction of a retrieval task that Sparck Jones calls the “core competency” of retrieval: a task that is necessary, but not sufficient, for user retrieval tasks. The abstraction facilitates research by controlling for (some) sources of variability, thus increasing the power of experiments that compare system effectiveness while reducing their cost. However, even within the highly-abstracted case of the Cranfield paradigm, meta-analysis demonstrates that the user/topic effect is greater than the system effect, so experiments must include a relatively large number of topics to distinguish systems’ effectiveness. The evidence further suggests that changing the abstraction slightly to include just a bit more characterization of the user will result in a dramatic loss of power or increase in cost of retrieval experiments. Defining a new, feasible abstraction for supporting adaptive IR research will require winnowing the list of all possible factors that can affect retrieval behavior to a minimum number of essential factors.     

Dyslipidaemia Associated with Type 2 Diabetics with Micro and Macrovascular Complications among Ghanaians

In this study, differences in lipid levels amongst diabetics with and without complications were assessed to determine lipid disorders that are associated with diabetic complications other than cardiovascular diseases. A Cross sectional study design was employed. The study included 288 diabetics and 108 non diabetics with different types of complications such as hypertension, nephropathy, neuropathy, and retinopathy. The mean serum total cholesterol was higher in patients with complications compared to those without complications and the non-diabetic controls. The normotensive diabetic patients had the lowest total cholesterol among the diabetic patients’ groups (4.65 ± 0.17 mmol/l) compared to the diabetics with hypertension (6.051 ± 0.20 mmol/l), retinopathy (6.26 ± 0.29 mmol/l), neuropathy (5.80 ± 0.17 mmol/l) and nephropathy patients 5.74 ± 0.26 mmol/l (P < 0.05). The prevalence of dyslipidaemia among diabetic subjects was between 19.2 and 84.0%. The study shows that, in addition to macrovascular complications, dyslipidaemia is common in type 2 diabetes mellitus patients with microvascular complications.     

Challenges of scholarly publications on the Web to the evaluation of science—A comparison of author visibility on the Web and in print journals

This article reveals different patterns of scholarly communication in the XML research field on the Web and in print journals in terms of author visibility, and challenges the common practice of exclusively using the ISI’s databases to obtain citation counts as scientific performance indicators. Results from this study demonstrate both the importance and the feasibility of the use of multiple citation data sources in citation analysis studies of scholarly communication, and provide evidence for a developing “two tier” scholarly communication system.     

The effects of different body positions on the accuracy of ultra-short-term heart rate variability indexes

PurposeWith the increasing popularity of ultra-short heart rate variability (HRV) measurements being utilized with mobile devices outside of controlled, research settings, it is important to determine the proper methodology to ensure accuracy. Therefore, the purpose of this study was to examine the validity of ultra-short-term HRV metrics across three different body positions in recreationally active individuals.MethodsTwenty-six subjects (12 males: 24.1 ± 3.6 yrs., 178.6 ± 6.4 cm, 82.9 ± 8.7 kg; 15 females: 21.3 ± 1.2 yrs., 170.7 ± 10.5 cm, 71.6 ± 18.9 kg) participated in 10-min electrocardiogram recordings in the supine, seated, and standing positions. HRV analysis using a variety of time, frequency, and non-linear parameters were performed following traditional recommendations (i.e., last 5 min of each 10-min recording) and ultra-short-term recordings (i.e., 1-min epoch following a 1-min stabilization period).ResultsSlight decreases (e.g., “near perfect” to “very large”) in intraclass correlations (ICC) and increases in the limits of agreement (LOA) were noted for most of the HRV metrics as position changed to sitting and then standing. However, throughout all three positions, the highest ICC values (0.88 to 0.92) and tightest LOA (CE ± 1.96 SD) were displayed in RMSSD.ConclusionsThis study supports the use of RMSSD and SD1 for assessing HRV under ultra-short-term recordings of 1 min regardless of position. However, practitioners should be consistent with the preferred position for measurements and not use them interchangeably to reduce potential errors during long-term monitoring.     

Mean escape time of switched Riccati differential equations

Riccati differential equations are a class of first-order quadratic ordinary differential equations and have various applications in systems and control theory. In this study, we analyzed a switched Riccati differential equation driven by a Poisson-like stochastic signal. We specifically focused on computing the mean escape time of the switched Riccati differential equation. The contribution of this study is twofold. We first show that, under the assumption that the subsystems described as deterministic Riccati differential equations escape in finite time regardless of their initial state, the mean escape time of the switched Riccati differential equation admits a power series expression. To further expand the applicability of this result, we then present an approximate formula to compute the escape time of deterministic Riccati differential equations. Numerical simulations were performed to illustrate the obtained results.     

Modeling the usefulness of search results as measured by information use

The documents retrieved by a web search are useful if the information they contain contributes to some task or information need. To measure search result utility, studies have typically focused on perceived usefulness rather than on actual information use. We investigate the actual usefulness of search results—as indicated by their use as sources in an extensive writing task—and the factors that make a writer successful at retrieving useful sources. Our data comprise 150 essays written by 12 writers whose querying, clicking and writing activities were recorded. By tracking authors’ text reuse behavior, we quantify the search results’ contribution to the task more accurately than before. We model the overall utility of the search results retrieved throughout the writing process using path analysis, and compare a binary utility model (Reuse Events) to one that quantifies a degree of utility (Reuse Amount). The Reuse Events model has greater explanatory power (63% vs. 48%); in both models, the number of clicks is by far the strongest predictor of useful results—with β-coefficients up to 0.7—while dwell time has a negative effect (β between −0.14 and −0.21). As a conclusion, we propose a new measure of search result usefulness based on a source’s contribution to an evolving text. Our findings are valid for tasks where text reuse is allowed, but also have implications on designing indicators of search result usefulness for general writing tasks.     

The role of the internet in information seeking. Putting the networked services in context

The author explores the place of the internet among other sources and channels in information seeking. Both qualitative and quantitative data were combined in the study. In 1997, the author conducted 23 theme interviews in Tampere, Finland, Secondly, the data of the national survey on the use of information technology at Finnish households conducted in 1996, based on the interviews of 2360 persons, aged 10–74 yr, were utilized. Both the features of job-related and nonwork information seeking will be discussed; however, the emphasis is on the latter. The conceptual framework of the study draws on the findings of the studies of computer-mediated communication and the uses and gratifications approach; the ideas of the ‘media richness’ theory and the ‘social influence’ theory are also utilized. E-mail and WWW appeared to be the most frequently used services in information seeking, but discussion groups and IRC were also utilized to some extent. The major research criteria for preferring the internet are the (relative) easiness of accessing a huge amount of data, savings in time and money, the opportunity to consult a number of experts simultaneously and a greater independence of certain time and place in information seeking. Thus far, the internet has not been able to supplant other sources and channels but rather complements them. This is evident, for example, in the utilization of electronic newspapers in the search for orienting information.     

Experiments in discourse analysis impact on information classification and retrieval algorithms

Researchers in indexing and retrieval systems have been advocating the inclusion of more contextual information to improve results. The proliferation of full-text databases and advances in computer storage capacity have made it possible to carry out text analysis by means of linguistic and extra-linguistic knowledge. Since the mid 80s, research has tended to pay more attention to context, giving discourse analysis a more central role. The research presented in this paper aims to check whether discourse variables have an impact on modern information retrieval and classification algorithms. In order to evaluate this hypothesis, a functional framework for information analysis in an automated environment has been proposed, where the n-grams (filtering) and the k-means and Chen’s classification algorithms have been tested against sub-collections of documents based on the following discourse variables: “Genre”, “Register”, “Domain terminology”, and “Document structure”. The results obtained with the algorithms for the different sub-collections were compared to the MeSH information structure. These demonstrate that n-grams does not appear to have a clear dependence on discourse variables, though the k-means classification algorithm does, but only on domain terminology and document structure, and finally Chen’s algorithm has a clear dependence on all of the discourse variables. This information could be used to design better classification algorithms, where discourse variables should be taken into account. Other minor conclusions drawn from these results are also presented.     

苄基异喳啉生物碱在木兰亚纲等植物类群中的分布

本文详细讨论了苄基异喹啉生物碱的生源和进化趋势，化学结构类型的分布规律，植 物来源，药理作用以及它们之间的联系性。研究表明：苄基异喹啉生物碱主要存在于较原始 的木兰亚纲植物群中，阿朴菲型、双苄基异喹啉型、原小檗碱型为普遍存在的结构类型。由于 按生源路线产生的不同结构类型在植物中呈现有规律的分布，因此苄基异喹啉生物碱可作为很好的分类学指标。     

白豆杉的胚胎发育及其系统位置的商榷

白豆杉属(Pseudotaxus Cheng)是我国裸子植物特有属之一,它的胚胎发育十分类似于红豆   杉属。白豆杉受精卵经4次有丝分裂,形成16个游离核的原胚,紧接着形成细胞壁。简单多   胚普遍存在,但没有裂生多胚。在后期胚胎发育中,根原始细胞主要向上分化形成原形成层和   胚皮层,向下提供根冠较少。因此,根冠组织弱小,而次生胚柄系统则十分发达。成熟胚具2   枚子叶,下胚轴中没有髓部,也没有任何分泌分子。     通过白豆杉胚胎发育的研究,作者认为白豆杉属在红豆杉科中的排列位置是：红豆杉属、   白豆杉属、澳洲红豆杉属、穗花杉属和榧树属。其中红豆杉属和白豆杉属比较原始,而榧树属   则比较进化。同时作者认为：从胚胎学资料看,将红豆杉科从松柏目中分离出来,单独成立红  豆杉目,这种观点得不到支持。