bluuebunny/crossref_metadata_2025 huggingface dataset:
Detuning characteristics of the linewidth enhancement factor of a midinfrared quantum cascade laser
Authors: Kumazaki Naoki , Takagi Yohei , Ishihara Mikito , Kasahara Kenichi , Sugiyama Atsushi , Akikusa Naota , Edamura Tadataka
Published: March 2008

The linewidth enhancement factor of a 5μm distributed feedback (DFB) quantum cascade laser above the threshold current detuned from the gain peak was investigated. This laser oscillates in two DFB modes located on either side of the gain peak. Using the optical feedback self-mixing method, we have observed variations in the linewidth enhancement factor, deviating from zero. The signs of the two DFB modes are both negative, which was verified by comparing their waveforms with that of conventional 1.55μm laser diodes, suggesting that the gain curve is asymmetric with respect to the gain peak.
Regulation of the proapoptotic factor Bax by Ku70-dependent deubiquitylation
Authors: Amsel Avigail D. , Rathaus Moran , Kronman Noam , Cohen Haim Y.
Published: March 2008

The DNA end-joining protein Ku70 is one of several proteins that inhibit apoptosis by sequestering the proapoptotic factor Bax from the mitochondria. However, the molecular mechanism underlying Ku70-dependent inhibition of Bax is not fully understood. Here, we show that the absence of Ku70 results in the accumulation of ubiquitylated Bax. Under normal growth conditions, Bax ubiquitylation promotes its degradation. Upon induction of apoptosis in wild-type cells, a significant reduction in the levels of ubiquitylated Bax was observed, whereas in Ku70
−/−
cells, the ubiquitylated Bax was robustly accumulated. Addition of recombinant Ku70 into a protein extract of Ku70
−/−
cells resulted in a decrease in the levels of ubiquitylated Bax, even in the presence of proteasome inhibitors. Moreover, an
in vitro
deubiquitylation assay demonstrated that recombinant Ku70 hydrolyzed polyubiquitin chains into monoubiquitin units. Thus, Ku70 regulates apoptosis by sequestering Bax from the mitochondria and mediating Bax deubiquitylation. These results shed light on the role of proteasome inhibitors as tumor suppressors.
From time series to complex networks: The visibility graph
Authors: Lacasa Lucas , Luque Bartolo , Ballesteros Fernando , Luque Jordi , Nuño Juan Carlos
Published: March 2008

In this work we present a simple and fast computational method, the
visibility algorithm
, that converts a time series into a graph. The constructed graph inherits several properties of the series in its structure. Thereby, periodic series convert into regular graphs, and random series do so into random graphs. Moreover, fractal series convert into scale-free networks, enhancing the fact that power law degree distributions are related to fractality, something highly discussed recently. Some remarkable examples and analytical tools are outlined to test the method's reliability. Many different measures, recently developed in the complex network theory, could by means of this new approach characterize time series from a new point of view.
Major evolutionary transitions in ant agriculture
Authors: Schultz Ted R. , Brady Seán G.
Published: March 2008

Agriculture is a specialized form of symbiosis that is known to have evolved in only four animal groups: humans, bark beetles, termites, and ants. Here, we reconstruct the major evolutionary transitions that produced the five distinct agricultural systems of the fungus-growing ants, the most well studied of the nonhuman agriculturalists. We do so with reference to the first fossil-calibrated, multiple-gene, molecular phylogeny that incorporates the full range of taxonomic diversity within the fungus-growing ant tribe Attini. Our analyses indicate that the original form of ant agriculture, the cultivation of a diverse subset of fungal species in the tribe Leucocoprineae, evolved ≈50 million years ago in the Neotropics, coincident with the early Eocene climatic optimum. During the past 30 million years, three known ant agricultural systems, each involving a phylogenetically distinct set of derived fungal cultivars, have separately arisen from the original agricultural system. One of these derived systems subsequently gave rise to the fifth known system of agriculture, in which a single fungal species is cultivated by leaf-cutter ants. Leaf-cutter ants evolved remarkably recently (≈8–12 million years ago) to become the dominant herbivores of the New World tropics. Our analyses identify relict, extant attine ant species that occupy phylogenetic positions that are transitional between the agricultural systems. Intensive study of those species holds particular promise for clarifying the sequential accretion of ecological and behavioral characters that produced each of the major ant agricultural systems.
Absence of equilibrium cluster phase in concentrated lysozyme solutions
Authors: Shukla Anuj , Mylonas Efstratios , Di Cola Emanuela , Finet Stephanie , Timmins Peter , Narayanan Theyencheri , Svergun Dmitri I.
Published: March 2008

In colloidal systems, the interplay between the short range attraction and long-range repulsion can lead to a low density associated state consisting of clusters of individual particles. Recently, such an equilibrium cluster phase was also reported for concentrated solutions of lysozyme at low ionic strength and close to the physiological pH. Stradner
et al.
[(2004) Equilibrium cluster formation in concentrated protein solutions and colloids.
Nature
432:492–495] found that the position of the low-angle interference peak in small-angle x-ray and neutron scattering (SAXS and SANS) patterns from lysozyme solutions was essentially independent of the protein concentration and attributed these unexpected results to the presence of equilibrium clusters. This work prompted a series of experimental and theoretical investigations, but also revealed some inconsistencies. We have repeated these experiments following the protein preparation protocols of Stradner
et al.
using several batches of lysozyme and exploring a broad range of concentrations, temperature and other conditions. Our measurements were done in multiple experimental sessions at three different high-resolution SAXS and SANS instruments. The low-ionic-strength lysozyme solutions displayed a clear shift in peak positions with concentration, incompatible with the presence of the cluster phase but consistent with the system of repulsively interacting individual lysozyme molecules. Within the decoupling approximation, the experimental data can be fitted using an effective interparticle interaction potential involving short-range attraction and long-range repulsion.
The rise and fall of excess male infant mortality
Authors: Drevenstedt Greg L. , Crimmins Eileen M. , Vasunilashorn Sarinnapha , Finch Caleb E.
Published: March 2008

The male disadvantage in infant mortality underwent a surprising rise and fall in the 20th century. Our analysis of 15 developed countries shows that, as infant mortality declined over two centuries, the excess male mortality increased from 10% in 1751 to >30% by approximately 1970. Remarkably, since 1970, the male disadvantage in most countries fell back to lower levels. The worsening male disadvantage from 1751 until 1970 may be due to differential changes in cause-specific infant mortality by sex. Declines in infant mortality from infections and the shift of deaths to perinatal conditions favored females. The reduction in male excess infant mortality after 1970 can be attributed to improved obstetric practices and neonatal care. The additional male infants who survived because of better conditions were more likely to be premature or have low birth weight, which could have implications for their health in later life. This analysis provides evidence of marked changes in the sex ratio of mortality at an age when behavioral differences should be minimal.
Evidence for degenerate tetraploidy in bdelloid rotifers
Authors: Mark Welch David B. , Mark Welch Jessica L. , Meselson Matthew
Published: March 2008

Rotifers of class Bdelloidea have evolved for millions of years apparently without sexual reproduction. We have sequenced 45- to 70-kb regions surrounding the four copies of the
hsp82
gene of the bdelloid rotifer
Philodina roseola
, each of which is on a separate chromosome. The four regions comprise two colinear gene-rich pairs with gene content, order, and orientation conserved within each pair. Only a minority of genes are common to both pairs, also in the same orientation and order, but separated by gene-rich segments present in only one or the other pair. The pattern is consistent with degenerate tetraploidy with numerous segmental deletions, some in one pair of colinear chromosomes and some in the other. Divergence in 1,000-bp windows varies along an alignment of a colinear pair, from zero to as much as 20% in a pattern consistent with gene conversion associated with recombinational repair of DNA double-strand breaks. Although pairs of colinear chromosomes are a characteristic of sexually reproducing diploids and polyploids, a quite different explanation for their presence in bdelloids is suggested by the recent finding that bdelloid rotifers can recover and resume reproduction after suffering hundreds of radiation-induced DNA double-strand breaks per oocyte nucleus. Because bdelloid primary oocytes are in G
1
and therefore lack sister chromatids, we propose that bdelloid colinear chromosome pairs are maintained as templates for the repair of DNA double-strand breaks caused by the frequent desiccation and rehydration characteristic of bdelloid habitats.
Noninvasive diagnosis of bronchial artery aneurysm using dual-source computed tomography angiography
Authors: Zhang Long Jiang , Yang Gui Fen , Lu Guang Ming
Published: March 2008

Bronchial artery aneurysm is a rare entity, detected in less than 1% of all patients undergoing selective bronchial arteriograms. Approximately 50 cases have been reported so far. Computed tomography (CT) reports of mediastinal bronchial artery aneurysms are rare. We report a case of a bronchial artery aneurysm in an 84-year-old male patient, which had been misdiagnosed as lung cancer for 6 years.
Is a flared stent effective for decreasing stent migration in canine prostatic urethra?
Authors: Woo Chul-Woong , Song Ho-Young , Yoon Chang Jin , Kim Tae-Hyung , Kim Eun-Young , Kim Jin Hyoung , Shin Ji Hoon
Published: March 2008

Background: Prostatic urethral stents are effective in relieving obstructions caused by benign prostatic hyperplasia (BPH). However, migration of these stents occurs frequently.

Purpose: To evaluate the efficacy of a flared stent for decreasing the migration rate in comparison with a straight stent in a canine prostatic urethral model.

Material and Methods: The flared stent (15 mm in diameter and 20 mm in length) was flared up to 19 mm at both ends to prevent migration. A straight stent with the same size was straight without flaring. Both stents were made of a nitinol wire filament and covered with an expanded polytetrafluoroethylene (ePTFE) membrane. The flared stent was inserted in the prostatic urethra of 10 dogs (group 1) and the straight stent in the prostatic urethra of 12 dogs (group 2). Follow-up retrograde urethrography (RUG) was performed 1, 4, and 8 weeks after stent placement. Fisher's exact test was used to compare the migration rate between the two groups. When stent migration occurred during the follow-up period, the same type of stent was inserted again.

Results: Three of 10 (30.0%) flared stents migrated into the urinary bladder between 1 week and 4 weeks after placement. Seven of 12 (58.3%) straight stents migrated into the urinary bladder 1 ( n = 3), 4 ( n = 1), and 8 ( n = 3) weeks following placement. The flared stent group showed lower migration rate than the straight stent group, but the migration rate did not reach statistical significance ( P = 0.231). After the second stent placement, one of three (33.3%) flared stents migrated again after 4 weeks and two of seven straight stents (28.6%) after 1 week.

Conclusion: Although the migration rate was not statistically significant, the flaring of the stent seemed to reduce the migration rate in comparison with straight stents in a canine prostatic urethral model. However, the migration rate of the flared stent was still high, and further developments are required to decrease migration rate.
Fluid-modulated bipolar radiofrequency ablation: an ex-vivo evaluation study
Authors: Bruners P. , Müller H. , Günther R. W. , Schmitz-Rode T. , Mahnken A. H.
Published: March 2008

Background: The effect of radiofrequency ablation (RFA) can be modulated by fluid injection.

Purpose: To evaluate the potential of different fluids to modulate the effect of bipolar RFA in an ex-vivo liver model.

Material and Methods: A bipolar RFA system with an internally cooled needle-shaped applicator (20-mm active tip) was used to induce coagulation lesions in ex-vivo porcine liver. Prior to the ablation procedure, 1-ml samples of seven different fluids were injected (0.9% saline, gadopentetate dimeglumine, ioxithalamate, 10% hydroxyethyl starch, 5% glucose, 95% ethanol, distilled water). Each fluid was used for five RF ablations. During the procedure, applied energy, impedance, and time were recorded. Additionally, temperature was measured at a fixed distance of 0.5 and 1.0 cm from the RF probe. Generator output was set to 20 W, as recommended by the vendor. Five ablation procedures without fluid injection served as the reference standard. The lesion diameters were measured, and volume and an efficiency index (coagulation volume/procedure duration) calculated and compared (ANOVA, Student-Newman-Keuls test).

Results: In comparison to the reference standard, fluid injection resulted in an enlargement of mean coagulation volume for all fluids. In comparison to RF ablation alone (1.42±0.33 cm3), significant increase ( P<0.001) of lesion size was found using gadopentetate dimeglumine, hydroxyethyl starch, glucose, and ethanol. The largest lesions were generated using preinjection of hydroxyethyl starch. Most energy could be applied after injection of glucose. Comparing the efficiency index, no statistically significant differences were found.

Conclusion: Besides the modulation of the electrical conductivity, the increase in thermal conductivity also contributes to the enhancement of RFA by the injection of the tested fluids. Further studies are needed to evaluate this effect for larger injection volumes under in-vivo conditions.
What are radiologists doing to prevent contrast-induced nephropathy (cin) compared with measures supported by current evidence? a survey of european radiologists on cin associated with computed tomography
Authors: Fishman E. K. , Reddan D.
Published: March 2008

Background: Contrast-induced nephropathy (CIN) is a serious complication of the use of iodinated contrast media (CM), and is associated with increased morbidity and mortality.

Purpose: To investigate whether radiologists take sufficient measures to prevent CIN in computed tomography (CT).

Material and Methods: 2005 survey of 509 European radiologists who had ⩾3 years' experience and performed ⩾50 CT scans/week.

Results: The most common methods used to identify patients at risk of CIN were renal function measurements (64%), clinical judgment (55%), and patient questionnaires (31%); 9% made no routine attempt to identify at-risk patients. The most common preventive protocols used in at-risk patients included: intravenous (i.v.) saline volume repletion (59%) or oral hydration (52%) before/after CT; use of low-osmolar CM (LOCM; 40%) or isosmolar CM (IOCM; 36%); and N-acetylcysteine (20%); 8% used no hydration regimen. While 78% of respondents used ⩽100 ml of CM in high-risk patients, 14% used ⩽150 ml, and 9% set no volume limit. For 57% of respondents, osmolality was the most important attribute in choosing an iodinated CM in at-risk patients; 41% agreed that CIN risk is lower with IOCM versus LOCM (31% disagreed).

Conclusion: A European radiologist survey identified a need for increased implementation of evidence-based protocols to improve CIN prevention: routine identification of at-risk patients; withdrawal of nephrotoxic drugs; use of volume repletion regimens; lowest possible volume of CM; and appropriate CM.
Building muscle: nutrition to maximize bulk and strength adaptations to resistance exercise training
Authors: Tarnopolsky Mark A.
Published: March 2008

Several nutritional strategies can optimize muscle bulk and strength adaptations and enhance recovery from heavy training sessions. Adequate energy intake to meet the needs of training and carbohydrate intake sufficient to maintain glycogen stores (>7 g carbohydrate·kg−1·day−1 for women; >8 g carbohydrate·kg−1·day−1 for men) are important. Dietary protein intake for top sport athletes should include some foods with high biological value, with a maximum requirement of approximately 1.7 g·kg−1·day−1 being easily met with an energy sufficient diet. The early provision of carbohydrate (>1 g·kg−1) and protein (>10 g) early after an exercise session will enhance protein balance and optimize glycogen repletion. Creatine monohydrate supplementation over several days increases body mass through water retention and can increase high‐intensity repetitive ergometer performance. Creatine supplementation can enhance total body and lean fat free mass gains during resistance exercise training; however, strength gains do not appear to be enhanced versus an optimal nutritional strategy (immediate post‐exercise protein and carbohydrate). Some studies have suggested that β‐OH‐methyl butyric acid (β‐HMB) can enhance gains made through resistance exercise training; however, it has not been compared “head to head” with optimal nutritional practices. Overall, the most effective way to increase strength and bulk is to perform sport‐specific resistance exercise training with the provision of adequate energy, carbohydrate, and protein. Creatine monohydrate and β‐HMB supplementation may enhance the strength gains made through training by a small margin but the trade‐off is likely to be greater bulk, which may be ergolytic for any athlete participating in a weight‐supported activity.
A DOUBLE BLIND CROSS OVER TRIAL OF GONADOTROPHIN RELEASING HORMONE (LHRH) IN SEXUALLY IMPOTENT MEN
Authors: DAVIES TERRY F. , MOUNTJOY C. Q. , GOMEZ‐PAN A. , WATSON M. J. , HANKER J. P. , BESSER G. M. , HALL REGINALD
Published: March 2008

A double blind cross over trial of 500 μg of gonadotrophin releasing hormone or placebo subcutaneously every 8 h for 4 weeks in ten men with secondary sexual impotence is reported. No obvious clinical improvement occurred but statistical analysis of a libido score showed some overall improvement, especially the spontaneous occurrence of erections during the treatment period (P < 0.05).
Cholesterol absorption, elimination and synthesis in coeliac disease
Authors: VUORISTO MATTI , MIETTINEN TATU A.
Published: March 2008

Abstract. Hypocholesterolaemia and high faecal elimination of cholesterol was explored by measuring the percentage of cholesterol absorbed, faecal steroids, serum cholesterol and dietary cholesterol in patients with coeliac disease before and after a gluten free diet. From these data, the total and endogenous flux of cholesterol into the gut and the amount of cholesterol absorbed could be calculated.

The mean faecal bile acid excretion was normal, but faecal endogenous steroids and thus faecal total steroids, and the cholesterol synthesis, were increased in the patients. The percentage of cholesterol absorbed was quite low (15·1±2·1 (SEM) v. 34·1 ± 2·5 in the controls), and it was attributable to a mucosal damage in the upper small intestine, suggesting that this played a primary role in the high faecal sterol loss. However, the influx of endogenous cholesterol into the gut had increased, so that in absolute terms the absorption of cholesterol was low only inconsistently. The glutenfree diet caused the opposite changes in the absorption percentage and influx of cholesterol into the gut, while the amount of cholesterol absorbed was only insignificantly increased.

Serum cholesterol was significantly correlated with the cholesterol absorbed (r= 0·36; P<0·01), faecal endogenous steroids (r= ‐0·30; P<0·05), and cholesterol synthesis (r= ‐0·29; P<0·05). Furthermore, the rise in serum cholesterol during the gluten‐free diet correlated negatively with the changes in cholesterol (r=‐0·55; P<0·05) and bile acid (r=‐0·77; P<0·01) synthesis. These associations and the lack of correlations between the amounts of cholesterol absorbed and synthesized suggest that the serum cholesterol level and regulation of cholesterol synthesis are interrelated in coeliac disease.
Gastric acid regulates the release of plasma secretin in man
Authors: GREENBERG G. R. , McCLOY R. F. , BARON J. H. , BRYANT M. G. , BLOOM S. R.
Published: March 2008

Abstract. Fasting plasma secretin determined in nine healthy subjects, twelve patients with active duodenal ulcer and four with Zollinger‐Ellison syndrome were 3·2±0·4, 5·1±1·2 and 20·3±1·3 pmol/l respectively (mean ±SEM). Cimetidine significantly (P<0·05) reduced levels in those with duodenal ulcer, as did gastric aspiration in the Zollinger‐Ellison group. A significant correlation (P<0·001) was found between basal acid output and mean fasting plasma secretin. After a solid meal and subsequent liquid soft drink, no sustained mean rise in plasma secretin was observed; changes in secretin appeared to coincide in time with rapid falls in duodenal pH, though little relationship could be established between the absolute level of pH and changes in plasma secretin. The mean peak post‐prandial rise in plasma secretin observed after solids was significantly (P<0·05) greater in duodenal ulcer patients than controls (9·1±1·1 versus 6·7±0·5 pmol/l) as was the mean integrated post‐prandial release (1002±110 versus 710±67 pmol min‐1 l‐1). Cimetidine reduced both rises (P<0·05) and was associated with significantly less duodenal pH readings below 4 (P<0·001). These results suggest that gastric acid is a major release mechanism for plasma secretin both fasting and after meals but it is likely the acid load rather than absolute pH in the duodenum which determines circulating levels.
Information management in service industries: towards a strategic framework
Authors: Beaumont J. R. , Walters D.
Published: March 2008

Abstract. Investments in information and communications technologies are largescale, and often the real potential is not being realized. It is stressed that an information systems strategy should be aligned with the business strategy, and the management of the information resource is discussed by considering the components of a strategic framework. Aspects of implementation in the service sector are illustrated through a brief discussion of different variables which could be measured.
End‐user software training: an experimental comparison of methods to enhance motivation
Authors: Olfman L , Bostrom R P
Published: March 2008

Abstract. Effective training is a key factor in determining the success of end‐user computing (EUC) in organizations. Software training research often focuses on one outcome of training – understanding. The experimental study reported here examines understanding, motivation, and use as outcomes of software training. Two methods of training, applications‐based and construct‐based, that focused on different levels of personal relevance were compared. The experiment utilized subjects in a ‘real’ training setting. The effects of previous experience with software were strong. There is some evidence to suggest that applications‐based training is best for novices.
Evaluation of EIS from a managerial perspective1
Authors: Bergeron F. , Raymond L.
Published: March 2008

Abstract. While executive information systems (EIS) constitute a rising trend in the use of information technology in organizations, much is still unknown in terms of the attributes an EIS should possess in order to increase the probability of successful implementation. A survey was conducted on 28 Canadian organizations, with 52 users giving their perceptions on the various attributes of EIS. Results indicate that the more important aspects relate to the quality of information and the benefits provided by EIS. Less important are the user‐interface and technical capabilities. User satisfaction with the attributes of their present system was also measured. In this regard, managers were more content with the quality of information and the user‐interface than with the benefits and the technical capabilities of their EIS. Overall, top‐managers were less satisfied with the present system than lower‐level managers.
Formal specification – an analytic tool for (management) information systems
Authors: Swatman PA , Swatman PMC
Published: March 2008

Abstract. There appears to be a general consensus within the information systems literature that formal specification of software systems is an inappropriate response to the perceived general failure of information systems to meet user requirements. Such views would seem to be based primarily on the difficulty of constructing formal specifications – and on the difficulty of understanding such specifications once constructed. Research into the applicability of formal methods has therefore tended to concentrate on the needs and the context of software developers specializing in critical and extremely complex software such as operating systems, transaction processing monitors, or nuclear reactor protection. More recently, however, formal methods have been applied successfully in more conventional and commercial areas, such as the development of a CASE tool, indicating that many of the perceived disadvantages of formal methods are merely myths.

This paper discusses the differing research directions of the information systems and software engineering disciplines and suggests that significant beneflts may result from a synthesis of the two approaches. We further suggest that there is a serious danger that approaches which have been shown to have value in one of the two domains are automatically being ignored in the other as being ‘irrelevant’. While each of the two areas ignores the contribution of the other, software systems will continue to be sub‐optimal (in terms of relevance, as well as quality). We argue the relevance of formal specifications to the information systems discipline, illustrating the argument with a case study based within the IS domain.
Information technology in support of individual decision‐making
Authors: Wood J. R. G. , Wood‐Harper A. T.
Published: March 2008

Abstract. The use of computers in organizations has often been justified by reference to the ‘improved decision‐making’ which will result from the use of new technology. Rarely, if ever, is any precise measurement given as to how such improvements will be judged. Phrases such as ‘better information leads to better decisions’ and ‘what managers require is more information’ dominate the literature on management information systems (MIS). Alistair Preston argues that this alignment with top management allowed MIS to legitimize and elevate itself as both a serious practice and an academic discipline.

The two dominant themes in the relationship between information technology (IT) and managerial decision‐making have been the use of Herbert Simon's work on decision‐making and Anthony's pyramidal structure of types of application system, the latter model leading to a powerful categorization of types of computer‐based information systems (i.e. transaction processing, management information systems, decision support systems, executive information systems). The models of decision‐making employed at each level of this hierarchy are those characterized by Simon as ‘objective rationality’ and ‘bounded rationality’ and these models encourage a view of information as representing some objective reality which can be captured, stored and processed within some form of technology. Dick Boland has argued forcibly that Simon's work has been crucial to the current level of understanding of information and technology within organizations.

Less concern has been given, however, to the role which IT itself plays in reinforcing this rationalistic view of information and decision‐making. As Mitroff has pointed out, to represent (or model) a problem is to conduct an inquiry into its nature. Likewise, Dick Boland suggests that information technologies are themselves social inventions that are malleable and shaped during use but that such sets limits and opens possibilities that shape the users as well. Hence, information technologies both incorporate and give rise to changes in our vocabularies for knowing ourselves and our institutions. It will not be enough, therefore, for us merely to change our existing models of managerial decision‐making, it will also be necessary to design new technologies which will reflect and encourage the use of such models.

In this paper we shall use the framework provided by Mitroff to try to consider a number of different paradigms of inquiring system and to see what technological forms would need to be developed in order that we may provide technological support for individual decision‐making based on each paradigm.
The effects of an intrinsically motivating instructional environment on software learning and acceptance
Authors: Davis S. , Bostrom R. P.
Published: March 2008

Abstract The most important goal of computer software training and interface design has been to help users learn and use software effectively. While research has provided useful information about how to achieve this outcome, it appears to have overlooked the contribution that ‘fun’ and ‘motivation’ can add to learning. This study develops and tests a model of the relationship between intrinsically motivating software instruction and two outcome variables — learning performance and perceived ease of software use. The researchers manipulated two design variables to create learning environments that were either high or low in intrinsic motivation. One variable, the computer interface, consisted of either a direct manipulation interface (the Macintosh Finder), defined as being high in intrinsic motivation, or a command‐based interface (disk operating system — DOS), which was less motivating. The second design variable, training method, also consisted of two categories — exploration training (more motivating) and instruction‐based training (less motivating). Additionally, the study evaluated the motivational impact of one individual characteristic — cognitive spontaneity. Results of a laboratory experiment indicated that subjects using the direct manipulation interface found the learning experience more intrinsically motivating and performed better in hands‐on computer tasks than in command‐based subjects. Also, subjects who were high in cognitive spontaneity were more likely to report the learning experience as intrinsically motivating. Learners who reported high levels of intrinsic motivation performed better in hands‐on tasks than those who did not, and perceived the software as easier to use. Exploration training, however, failed to exhibit a positive relationship to intrinsic motivation. These results suggest that an intrinsically motivating instructional environment can lead to improved software learning and performance. This is explained in terms of four key dimensions spanning multiple theories of intrinsic motivation: challenge, curiosity, control and fantasy.
Evaluating organizational efficiency resulting from information technology investment: an application of data envelopment analysis
Authors: Mahmood M. A.
Published: March 2008

Abstract. Even during this recessionary era, information technology (IT) expenditure in most organizations continues to grow at a high rate. Because of this increased IT expenditure, more and more senior managers are demanding that IT play a greater role in determining their firm's success by helping them increase organizational efficiencies and perhaps even achieve competitive advantage. The existing information systems literature on IT investment and organizational strategic performance, however, provides very little help to senior managers in making before‐the‐fact IT investment decisions. The present research study puts forth some ‘hard’ evidence relating IT investment to organizational strategic and economic performance by using data envelopment analysis (DEA). Eight IT investment measures were used as inputs and 10 organizational strategic and economic performance ratios were used as outputs for the DEA model. The results indicate that two‐thirds of the organizations in this research study are deemed efficient by DEA. A clear distinction exists between the efficient group and the inefficient group in terms of IT investment and organizational strategic and economic performance. The firms in the efficient group had a much higher return on their information technology investment than the inefficient group. In addition, the DEA results pinpoint the inefficient inputs and deficient outputs for an inefficient firm allowing a senior manager to take corrective actions to compensate for the situation.
An exploration of the problems of using function points mark II
Authors: Hughes R.
Published: March 2008

Abstract. This paper examines critically the function point analysis mark II (FPA mark II) method of measuring the functionality of information systems. Although the focus of the paper is on FPA mark II as devised by Symons, both this and the Albrecht method, from which the FPA mark II was developed, are briefly discussed. The published attempts to validate FPA mark II are reviewed and then the problems encountered by the author in applying the approach are described. The final part of the paper is concerned with the fit between SSADM and FPA mark II.
Evolving information systems: meeting the ever‐changing environment
Authors: Oei J. L. H. , Proper H. A. , Falkenberg E. D.
Published: March 2008

Abstract. To meet the demands of organizations and their ever‐changing environment, information systems are required which are able to evolve to the same extent as organizations do. Such a system has to support changes in all time‐and application‐dependent aspects. In this paper, requirements and a conceptual framework for evolving information systems are presented. This framework includes an architecture for such systems and a revision of the traditional notion of update. Based on this evolutionary notion of update (recording, correction and forgetting) a state transition‐oriented model on three levels of abstraction (event level, recording level, correction level) is introduced. Examples are provided to illustrate the conceptual framework for evolving information systems.
Timing the introduction of information technology
Authors: Post G. V. , Lau K.‐Na. , Kagan A.
Published: March 2008

Abstract. Deciding when to adopt or introduce new information technology (IT) is a relatively difficult problem. This paper presents a method that can be used in many circumstances to evaluate new IT. The model is based on modelling the response of customers and rivals to services provided by IT. The methodology recognizes competitor reactions on two levels: within the local market and actions by rivals in the international market. The model examines behaviour, costs, and benefits over time. Several different types of models are examined, ranging from competitive (Nash) equilibriums to joint ventures. This model is illustrated by examining when banks should implement new technology. The results indicate that large banks can effectively utilize technology as a strategic weapon. Smaller, local banks are more limited in their control of technology. The model reveals some strategic uses that are not evident from existing models.
Dialectical hermeneutics: a theoretical framework for the implementation of information systems
Authors: Myers M. D.
Published: March 2008

Abstract. Despite the proliferation of information technology, the implementation of information systems remains problematic. Many systems fail to live up to expectations and some end up as disasters. Research on implementation has been conducted for the past two decades, but no theoretical framework for IS implementation has been widely accepted. This paper proposes dialectical hermeneutics as a theoretical framework for IS implementation research. Dialectical hermeneutics, as an integrative theoretical framework, combines both interpretive and critical elements, and addresses those social and organizational issues which are critical to the successful implementation of information systems. The case study research method was used to examine the implementation of systems in three organizations.
Ethical theory, codes of ethics and IS practice
Authors: Walsham Geoff
Published: March 2008

Abstract. Ethical issues, with respect to computer‐based information systems, are important to the individual IS practitioner. These same issues also have an important impact on the moral well‐being of organizations and societies. Considerable discussion has taken place in the Information Systems (IS) literature on specific ethical issues, but there is little published work which relates these issues to mainstream ethical theory. This paper describes a range of ethical theories drawn from philosophy literature and uses these theories to critique aspects of the newly revised ACM Code of Ethics. Some in the IS field on problematic ethical issues which are not resolved by the Code are then identified and discussed. The paper draws some implications and conclusions on the value of ethical theory and codes of practice, and on further work to develop existing ethical themes and to promote new initiatives in the ethical domain
The capability maturity model and CASE
Authors: Mathiassen L. , Sørensen C.
Published: March 2008

Abstract. Many software organizations face serious problems in their attempts to make expectations and realities meet in introducing CASE technology. One promising approach to understanding CASE introduction better and to managing it more effectively has been developed by relating CASE introduction to the Capability Maturity Model (CMM). This paper reviews software process maturity as a framework for CASE introduction. The relevance of the framework is discussed and three critical questions are explored: 1) What is the role of organizational experiments in CASE introduction? 2) How do the functional characteristics of CASE technology influence CASE introduction? and 3) How does the organizational context influence CASE introduction? The aim of the paper, by way of this discussion, is to explicate the strengths and limits of software process maturity as a framework for CASE introduction, and to identify the most important supplementary issues
Human‐machine dynamics in complex information systems: the ‘microworld’ paradigm as a heuristic tool for developing theory and exploring design issues
Authors: Wastell David
Published: March 2008

Abstract. The term ‘complex informated domain’ refers to a work environment characterized by high complexity and onerous cognitive demands, in which the management of a remote process is mediated by an information system (IS). Such work environments are typical of highly technical domains, such as industrial process control, but as computer‐based information systems penetrate ever deeper into modern businesses, all organizations are taking on the same ‘informated’ characteristics. This paper reports an experiment using a rich simulation (‘a microworld’), which attempted to throw light on human–machine dynamics in such complex environments. Two issues were investigated: the state of the subject (fatigue induced by sleep loss) and the degree of operator control (empowerment) afforded by the IS interface. Results showed that sleep deprivation led to no degradation in overt performance but, contrary to expectations, lower performance was associated with high control operation. A detailed qualitative analysis showed the high control interface to encourage a more proactive control style, whereas fatigue intensified primitive, reactive strategies. The findings emphasize that cognition is a goal‐directed, adaptive system not simply an information‐processing mechanism. A model of cognitive dynamics is outlined that distinguishes a hierarchy of control levels: anxiety defences, reactive control and strategic control. In general, the experiment shows the potential value to IS research of the microworld paradigm as a tool for developing theory and exploring key design issues.
Construction of self‐cloning industrial brewing yeast with high‐glutathione and low‐diacetyl production
Authors: Wang Zhao‐Yue , He Xiu‐Ping , Liu Nan , Zhang Bo‐Run
Published: March 2008

Self‐cloning strains of industrial brewing yeast were constructed, in which one allele of α‐acetohydroxyacid synthase (AHAS) gene (ILV2) was disrupted by integrating Saccharomyces cerevisiae genes, γ‐glutamylcysteine synthetase gene (GSH1) and copper resistant gene (CUP1) into the locus of ILV2. The self‐cloning strains were selected for their resistance to CuSO4 and identified by PCR amplification. The results of AHAS and glutathione (GSH) assay from fermentation with the self‐cloning strains in 500‐mL conical flask showed that AHAS activity decreased and GSH content increased compared with that of host yeasts. The results of pilot scale brewing in 5‐L fermentation tank also indicated that GSH content in beer fermented with self‐cloning strains T5‐3 and T31‐2 was 1.3 fold and 1.5 fold of that of host QY5 and QY31, respectively; and diacetyl content decreased to 64% and 58% of their hosts, respectively. The self‐cloning strains do not contain any heterologous DNA, they may be more acceptable to the public.
Cancer survivorship: evolutionary concept analysis
Authors: Doyle Natalie
Published: March 2008

Title.  Cancer survivorship: evolutionary concept analysis

Aim.  This paper is a report of a concept analysis of cancer survivorship in adults.

Background.  The concept of cancer survivorship appears frequently in cross‐discipline literature but does not seem to have any precise definition or meaning. Substantive research into the experience of surviving cancer is long overdue. However, if a concept has not been clearly defined any theoretical work based on that concept will also be unclear.

Data sources.  The analysis was based on literature published in English between 1994 and 2006 (n = 43) and seminal work in the field.

Review methods.  Rodgers’ method of evolutionary concept analysis was used, allowing the concept to be viewed within a sociocultural and temporal context and capturing both lay and emic perspectives.

Results.  Cancer survivorship in adults is a process beginning at diagnosis and involving uncertainty. It is a life‐changing experience with a duality of positive and negative aspects, and is unique to the individual but has some universality. The primary antecedent is a cancer diagnosis and the consequences can be divided into four main themes: physical health, psychological health, social health and spiritual health.

Conclusion.  Surviving cancer is now an established reality for millions of people worldwide. Nurses can benefit from a deeper understanding of the patient experience, both theoretically and in practice. Clarification of a concept provides a heuristic for further inquiry and a basis for theory generation.
Small non‐coding RNAs in Caulobacter crescentus
Authors: Landt Stephen G. , Abeliuk Eduardo , McGrath Patrick T. , Lesley Joseph A. , McAdams Harley H. , Shapiro Lucy
Published: March 2008

Small non‐coding RNAs (sRNAs) are active in many bacterial cell functions, including regulation of the cell's response to environmental challenges. We describe the identification of 27 novel Caulobacter crescentus sRNAs by analysis of RNA expression levels assayed using a tiled Caulobacter microarray and a protocol optimized for detection of sRNAs. The principal analysis method involved identification of sets of adjacent probes with unusually high correlation between the individual intergenic probes within the set, suggesting presence of a sRNA. Among the validated sRNAs, two are candidate transposase gene antisense RNAs. The expression of 10 of the sRNAs is regulated by either entry into stationary phase, carbon starvation, or rich versus minimal media. The expression of four of the novel sRNAs changes as the cell cycle progresses. One of these shares a promoter motif with several genes expressed at the swarmer‐to‐stalked cell transition; while another appears to be controlled by the CtrA global transcriptional regulator. The probe correlation analysis approach reported here is of general use for large‐scale sRNA identification for any sequenced microbial genome.
Multicentric/multifocal cerebral lesions: Can fluid‐attenuated inversion recovery aid the differentiation between glioma and metastases?
Authors: Stuckey SL , Wijedeera R
Published: March 2008

The purpose of the study was to assess whether non‐enhancing adjacent cortical signal intensity abnormality detected on fluid‐attenuated inversion recovery (FLAIR) can differentiate between multicentric and/or multifocal glioma and non‐glioma pathology in patients with multiple enhancing cerebral lesions. Nineteen MR studies were reviewed after a database search and exclusion criteria applied, to detect areas of FLAIR cortex involvement without enhancement. Statistical analysis was carried out using a 2 × 2 contingency table and Fischer’s exact ratio. Non‐enhancing adjacent cortical T2 signal abnormality was seen in eight of eight multicentric and/or multifocal gliomas and four of 11 of the non‐glioma pathologies (10 metastatic disease and 1 lymphoma). The presence of non‐enhancing adjacent cortical T2 signal abnormality had a sensitivity of 100% and specificity of 63% for glioma. The positive predictive value was 67% and negative predictive value 100%. Fischer’s exact probability test was P = 0.01 when applied to the glioma versus non‐glioma categories, indicating a significant difference. Non‐enhancing adjacent cortical T2‐weighted FLAIR signal appears to be more frequently seen in patients with glioma and multiple enhancing lesions compared with those with glioma and a solitary enhancing cerebral lesion. The absence of this sign favours metastatic disease and the presence suggests that multicentric and/or multifocal glioma should remain a consideration.
A case of neck ectopic meningioma
Authors: Sanei Mohammad Hossein , Berjis Nezamaldin , Mahzouni Parvin , Naimi Azar
Published: March 2008

Primary extra cranial and extra spinal meningioma is rare and is usually limited to the head and neck region or to the paravertebral soft tissues. Histologic diagnosis (in particular for fresh specimens) is often difficult. A 16‐year‐old girl with a cervical mass is presented. It was a relatively large mass with an approximate diameter of 5 cm. It was diagnosed in fine needle aspiration as a pleomorphic adenoma. Intra‐operative diagnosis was paraganglioma and frozen section suggested an infiltrative tumor. Histologically, the lesion showed uniform spindle cell proliferation separated by hyalinized collagen bundles. The cells were often arranged in sweeping fascicles and concentrically wrapped in tight whorls. Immunohistochemically, tumor cells were positive for epithelial membrane antigen and vimentin, while showing no reaction for cytokeratin, chromogranin, neuron‐specific enolase and thyroglobulin. A diagnosis of ectopic meningioma was established based on microscopic appearance and immunohistochemical profile of the tumor. Despite its rarity, ectopic meningioma should be considered in differential diagnosis of any mass lesion in head and neck regions, containing spindle cells.