bluuebunny/crossref_metadata_2025 huggingface dataset:
Personal competency of selected women construction project managers in Malaysia
Authors: Liyana Othman Nur , Jaafar Mastura
Published: September 2013

Purpose

– The aim of the current research is to assess the personal competency level of women project managers in the Malaysian construction industry.

Design/methodology/approach

– The study used stratified random sampling design on the listed Grade 7 contractor companies in Peninsular Malaysia. The questionnaire survey approach was used to collect data on 15 women project managers in Peninsular Malaysia.

Findings

– The results revealed that experience is the first criterion being used in selecting women project managers, whereas the three main personal competencies they exemplify are honesty and integrity, alertness and quickness, and decision-making ability.

Practical implications

– The result can be used as a guidance to measure the level of personal competency of women project managers.

Originality/value

– The current study provides insight into the competency exemplified by women project managers in Malaysia.
Teaching engineering and technology: cognitive, knowledge and problem-solving taxonomies
Authors: Barak Moshe
Published: September 2013

Purpose

– This paper aims to explore the objectives and methods of teaching engineering and technology education (ETE) through the lens of three educational taxonomies in cognitive, knowledge and problem-solving perspectives. This analysis is useful in light of today's increasing interest in teaching engineering and technology in K-12 education, instead of crafts or manual skills.

Design/methodology/approach

– This is an exploratory study. Technology and engineering education is a relatively new area in K-12 education, and little has been written about the use of general educational taxonomies for analysing and designing the teaching and learning of this subject.

Findings

– The literature analysis teaches us that fostering students' higher-order capabilities such as design and problem solving in engineering and technology cannot take place in isolation from specific knowledge. Instruction should be designed to: develop a certain degree of factual, procedural, conceptual and meta-cognitive knowledge in relevant areas of technology, science and mathematics; and engage learners in assignments of increasing cognitive levels, from simple to complex ones.

Originality/value

– This work is original and valuable in that it explores ETE through tools often used in the educational literature and research, rather than regarding technology education as an exceptional school subject. This could encourage making engineering and technology a core component in the overall curriculum.
Application of CAD and reverse engineering methodology for development of complex assemblies
Authors: Afeez Abdul , Sanjay Sanjay , Kumar Anjani
Published: September 2013

Purpose

– In the present paper, a CAD and reverse engineering (RE) methodology has been adopted for the development of a complex assembly of a TFC 280 crane cabin. A different approach has been adopted to eliminate fouling as well as interference with other components of the crane such as boom, gantry, front drum, rear drum, etc. with its cabin. The paper aims to discuss these issues.

Design/methodology/approach

– A dummy 3-D CAD model of the assemblies has been made using assembly constraints of Master Assembly and then checked for fouling and interference using IDEAS NX 12 to validate cabin design. In fabrication industries, one of the critical challenges is to maintain close geometric tolerances in finished products, which have been taken care of by the use of accurate value of K-factor.

Findings

– Ergonomics of the re-engineered crane cabin has also been improved by providing rear vision and improvement in operator's forward visibility from 165° to 180°.

Originality/value

– The work has been carried out using RE methodology un-used in this part of the world (Jamshedpur, India).
Stage-specific effects of the Sarbanes-Oxley Act
Authors: Ecer Sencer , Khalid Salman
Published: September 2013

Purpose

– The purpose of this paper is to empirically demonstrate that drivers of venture capital (VC) investments are different across three broadly defined sectors: high-technology manufacturing, medium-technology manufacturing and services, and low-technology services. Moreover, such differences also exist across industries within each of these sectors.

Design/methodology/approach

– The basic hypothesis is that “not only different stages of VC investments have different drivers, but VC investments in different sectors of the economy are also driven by different drivers.” The paper tests this hypothesis using a Poterba (1989) type supply and demand framework in the multivariate time-series regression analysis.

Findings

– This paper empirically demonstrates that drivers of VC investments are different across three broadly defined sectors: high-technology manufacturing, medium-technology manufacturing and services, and low-technology services. Moreover, such differences also exist by stages of investment and across industries within each of these sectors. In particular, the paper finds that the importance of the number of VC-led initial public offering (IPO) transactions as the main driver of VC investment decreases with the level of technology involved in the sector. IPO transactions are particularly important in software, networking and equipment, and business products and services industries. In contrast to earlier literature, however, the paper do not find a more pronounced effect of IPOs for seed and late stages of VC investments. Similarly, the positive impact Sarbanes-Oxley Act of 2002 – which mainly impacts public companies – also intensifies with a decrease in the level of technology involved in the sector, and the paper do not find a negative impact. The Act is important particularly for VC investments in medium- and low-tech sectors and in early or expansion stages.

Originality/value

– In analyzing the determinants of VC in a supply and demand framework as in Poterba (1989), the paper differentiates between different sectors (17 industries) and stages of VC (four stages: seed, early, expansion, late). Such level of differentiation is novel and allows more refined and better targeted public policy measures.
Social layers of customer-to-customer value co-creation
Authors: Rihova Ivana , Buhalis Dimitrios , Moital Miguel , Beth Gouthro Mary
Published: September 2013

Purpose

– Approached from the customer-dominant (C-D) logic perspective, this paper aims to extend current value co-creation discussions by providing conceptual insights into co-creation within customers' social sphere. Focusing on socially dense contexts in which customers consume together in dyads or collectives, the paper seeks to provide recommendations of how service managers can facilitate customer-to-customer (C2C) co-creation.

Design/methodology/approach

– The paper bridges current thinking on value within the C-D logic with service management perspectives on C2C interactions and social science concepts on consumer communities. Examples from literature and practice are drawn on in the discussion.

Findings

– The proposed framework reveals C2C co-creation as a dynamic, multi-layered process that is embedded in customers' social contexts. Value emerges in four distinctive social layers: “detached customers”, “social bubble”, “temporary communitas” and “ongoing neo-tribes”.

Research limitations/implications

– This paper is conceptual. Further validation of the framework in a variety of socially dense consumption settings is needed, using field-based qualitative methods such as participant observation and interviews.

Practical implications

– Awareness of the multi-layered nature of C2C co-creation and specific practices in which value is formed provides service managers with opportunities to create value propositions that help facilitate such co-creation. Service managers across various sectors benefit from understanding how customers can be “nudged” into more socially immersive co-creation layers.

Originality/value

– The paper contributes by introducing a C2C co-creation perspective, conceptualizing the social layers within which value is formed, and providing specific propositions to service managers with regard to servicescape structuring and other strategies that facilitate C2C co-creation.
Customer activity in service
Authors: Mickelsson Karl-Jacob
Published: September 2013

Purpose

– Customer activity in service has mainly been understood within the boundaries of interactions with service providers. This paper goes beyond this view to focus on the customer's independent activity, of which interaction is only a part. Moreover, the concept of customer activity remains largely unexplored and undefined. Hence, the purpose of this paper is to develop the concept of customer activity and to show how it can be applied in an empirical study.

Design/methodology/approach

– The paper reviews the concept of customer activity in service marketing. It then goes on to characterise and operationalise the concept, and finally apply it to an explorative study. The study contrasts customer activity from the provider's interaction-centric point of view with customer activity from the customer's own point of view.

Findings

– This paper defines customer activities as discrete sequences of behaviour that aim at creating or supporting some types of value in the customer's life or business. A customer-dominant perspective on customer activity allows companies to understand the role of their service in the various activities of different types of customers.

Originality/value

– The paper contributes to service research by bringing attention to the concept of customer activity and contrasting it with alternative concepts. The paper is the first to show how customers combine different activities (where service interaction is only one type) into systems, which they maintain to create value for themselves. By profiling customers according to activity systems, providers can understand their own role in the customer's network of value-creating activities.
Understanding participation in company social networks
Authors: Sofia Martins Carla , Patrício Lia
Published: September 2013

Purpose

– This article seeks to contribute to a better understanding of company social networks (CSNs), which constitute people connected to a company or brand through a social networking site. To this end, the research addresses both participation goals and CSN attributes that drive participation in CSNs.

Design/methodology/approach

– With a grounded theory approach, this research begins with an exploratory study of the page maintained by a large retailer for six months, followed by a qualitative study featuring in-depth individual interviews and focus groups with 26 members of the CSN.

Findings

– The results highlight differences between CSNs and other types of online communities (OCs). Members rely on the company to help them achieve their goals; few count on their CSN peers, with whom they maintain weak ties. Unlike in brand communities (BCs), most members are not enthusiasts but instead engage in a pragmatic relationship with the brand.

Practical implications

– CSNs can create value for both the host company and its members; active management is necessary to unlock that potential. The implications for CSN management include strategies to foster participation and increase value for companies and members.

Originality/value

– Although the previous research has studied OCs, specific research on CSNs is scarce. This study characterizes CSNs and provides details regarding participation factors in this new context, as well as relevant implications for CSN management and service research.
Reading and learning from screens versus print: a study in changing habits
Authors: Stoop Judith , Kreutzer Paulien , G. Kircz Joost
Published: September 2013

Purpose

– The aim of this paper is to research the difference in reading and learning from print versus electronic media in a professional and educational setting. To what extent does the materiality of the medium influence the efficiency and effectively of the reader? What is needed to create “digital born” information rich texts? In part 2 changing presentations of educational texts on paper, LCD screen and through a mind map are addressed.

Design/methodology/approach

– In depth comparative tests with a great number of subjects between print-on-paper, e-ink screens and LCD screens. In part 2 the results of learning from differently structured texts from paper, screen and mind maps respectively are reported. The subjects had to read the texts and subsequently had to answer knowledge questions about the content. Group discussions have been carried out thorough the test.

Findings

– All tests show that print-on-paper is still a superior medium for learning and digesting complicated and elaborate texts, while electronic screens are appreciated for quick information gathering, communication and navigation. Electronic representations of information and knowledge demands that the structure of the writing has to change.

Research limitations/implications

– Given the rapid development in electronic displays, many issues – in particular ergonomical – become a “moving target”. An important limitation – which is one of the quests of this research – is the lack of sufficient genuine digital born texts.

Practical implications

– The need is to start and review the writing process; the appearance but also the structure of information and knowledge rich texts. A second issue is the need to develop easy capabilities to make electronic texts as easy a “tool” as the print text with underlining, comments and notes.

Originality/value

– This is deep qualitative research in comparison with quantitative tests and a comparison between professional information acquisition and learning
Online gift-searching: gift-giving orientations and perceived benefits of searching
Authors: Jeng Shih-Ping
Published: September 2013

Purpose

– The increasing number of people who search for and purchase gifts online underscores the need to better understand the process of searching for gifts online. This study explores online gift-searching with regard to the psychological characteristics of gift seekers and the benefits of searching. This study examines how gift-giving orientations (agape and reciprocity) influence the perceived benefits of searching (utilitarian and hedonic) in online gift-searching behaviour.

Design/methodology/approach

– The conceptual framework was tested using a survey. The data were analysed using structural equation modelling.

Findings

– The results show that agape positively influences both utilitarian and hedonic benefits, which in turn increase online gift-searching. Reciprocity does not affect utilitarian benefits but decreases hedonic benefits and thus causes a reduction in online gift-searching. The perceived benefit of searching fully mediates the relationship between gift-giving orientations and online gift-searching. Utilitarian benefits are the primary benefits that are sought by consumers who search for gifts online.

Originality/value

– Previous research regarding online information searching has focused on searching for items for self-use. This study extends that research by focusing on gift giving. By analysing the mediating effects of both the utilitarian and hedonic benefits of searching, this study provides new insights into whether and how gift-giving orientations affect online gift-searching. Additionally this study offers guidelines for effectively managing online retail environments.
A study of the continuous usage intention of social software in the context of instant messaging
Authors: Hong Jinwon , (Daniel) Lee One-Ki , Suh Woojong
Published: September 2013

Purpose

– As social networking is becoming more popular, social software has achieved an important position in the internet business industry. For social software to be successful, it is crucial to understand how users form their continuous usage intentions toward social software. This paper aims to discuss these issues.

Design/methodology/approach

– Drawing upon socio-technical and social cognitive perspectives, this study proposes a theory-based model that investigates the interaction effects between social (i.e. perceived user base and relationship commitment) and technical (i.e. perceived system quality) factors of social software, in addition to their direct effects on continuous usage intentions. To empirically validate the proposed research model, a structural equation modelling technique was used.

Findings

– The results of our model test indicate that all relevant social and technical factors are significant determinants of continuous usage intention. Moreover relationship commitment exhibits a positive interaction effect with perceived system quality on continuous usage intention, while perceived user base does not.

Practical implications

– Service designers or providers of social software should make an effort to nurture social relationships among users, expand users' social networks, and reinforce users' relationship commitment to their friends.

Originality/value

– Given the lack of investigations into socio-technical interactions in prior social software studies, the theoretical perspectives and empirical findings of this study are useful to both academics and practitioners. The findings also raise new implications regarding the various types of interactions (e.g. enhancing or suppressing) between the social and technical factors around social software.
Web analytics of user path tracing and a novel algorithm for generating recommendations in Open Journal Systems
Authors: Taraghi Behnam , Grossegger Martin , Ebner Martin , Holzinger Andreas
Published: September 2013

Purpose

– The use of articles from scientific journals is an important part of research-based teaching at universities. The selection of relevant work from among the increasing amount of scientific literature can be problematic; the challenge is to find relevant recommendations, especially when the related articles are not obviously linked. This paper seeks to discuss these issues.

Design/methodology/approach

– This paper focuses on the analysis of user activity traces in journals using the open source software “Open Journal Systems” (OJS). The research questions to what extent end users follow a certain link structure given within OJS or immediately select the articles according to their interests. In the latter case, the recorded data sets are used for creating further recommendations. The analysis is based on an article matrix, displaying the usage frequency of articles and their user selected successive articles within the OJS. Furthermore, the navigation paths are analysed.

Findings

– It was found that the users tend to follow a set navigation structure. Moreover, a hybrid recommendation system for OJS is described, which uses content based filtering as the basic system extended by the results of a collaborative filtering approach.

Originality/value

– The paper presents two original contributions: the analysis of user path tracing and a novel algorithm that allows smooth integration of new articles into the existing recommendations, due to the fact that scientific journals are published in a frequent and regular time sequence.
Flax look‐alikes: Pitfalls of ancient plant fibre identification
Authors: Haugan E. , Holst B.
Published: September 2013

Plant fibres have been used since ancient times in numerous applications ranging from nets and basketry to textiles for clothing. A proper identification of plant fibre remains in archaeological excavations provides important information about resource exploitation and agriculture. In order to identify plant fibres, a series of fibre features—cross‐section diameter, lumen diameter, dislocations (nodes), cross markings, cross‐section shape and lumen shape—have been defined and characteristic traits of these features for different fibre types established. How suitable these traits really are for fibre identification has been a matter of debate. To resolve this issue, we have performed a systematic investigation of typical textile bast fibres: flax, nettle and hemp. We have investigated cross‐section diameter, lumen diameter, dislocations (nodes) and cross markings using standard compound, white light transmission microscopy. Our investigations show that all the traits that are considered characteristic for one type of plant fibre can also, on occasion, be found in other types. This demonstrates that an investigation of the traits listed above is not sufficient to ensure a correct identification of the plant fibre material; in particular, when only a small amount of material is available. This is often the case in archaeological excavations.
Psychosocial Benefits of Cross‐Ethnic Friendships in Urban Middle Schools
Authors: Graham Sandra , Munniksma Anke , Juvonen Jaana
Published: September 2013

To examine the unique functions of same‐ and cross‐ethnic friendships, Latino (n = 536) and African American (n = 396) sixth‐grade students (Mage = 11.5 years) were recruited from 66 classrooms in 10 middle schools that varied in ethnic diversity. Participants reported on the number of same‐ and cross‐ethnic friends, perceived vulnerability, friendship quality, and the private regard dimension of ethnic identity. Whereas same‐ethnic friendships were uniquely associated with stronger private regard, more ethnic diversity and cross‐ethnic friendships were uniquely associated with less perceived vulnerability. Multilevel structural equation modeling tested whether cross‐ethnic friendships mediated the diversity‐vulnerability relation. Although cross‐ethnic friendships did not significantly mediate this relation at the classroom level, these friendships predicted less vulnerability at the individual student level.
Value of Serial Echo‐Guided Ramp Studies in a Patient with Suspicion of Device Thrombosis after Left Ventricular Assist Device Implantation
Authors: Kato Tomoko S. , Colombo Paolo C. , Nahumi Nadav , Kitada Shuichi , Takayama Hiroo , Naka Yoshifumi , Di Tullio Marco R. , Homma Shunichi , Mancini Donna , Jorde Ulrich P. , Uriel Nir
Published: September 2013

Thrombus formation inside of the pump is a major cause for device malfunction following the left ventricular assist device (LVAD) implantation. We recently established a novel ramp test protocol facilitating continuous bedside echo monitoring to optimize LVAD function and diagnosing device malfunctions. We describe a case of 29‐year‐old woman undergoing HeartMate II LVAD implantation, in whom serial ramp studies were used to diagnose intra‐device thrombus after device implantation. The 1st ramp study at postoperative day (POD) 26 revealed adequate reduction in ventricular size according to the increase in LVAD speed (left ventricular end‐diastolic diameter [LVEDD] at minimum and maximum speeds, 68 and 37 mm, respectively). The patient was discharged home and received routine anticoagulation maintenance therapy. However, a 2nd ramp test was performed on POD 56 due to increased lactase dehydrogenase and brain natriuretic peptide levels and showed marked increase in left ventricle (LV) chamber size without adequate response to the LVAD speed changes (LVEDD at minimum and maximum speeds, 88 and 76 mm, respectively). Given the suspicion for partial pump thrombosis, the patient was immediately hospitalized and received intravenous heparin infusion. After the optimization of the intensive anticoagulation therapy, the patient underwent a 3rd ramp study, which showed a remarkable improvement of the adequate response to LVAD speed changes. The patients eventually underwent cardiac transplant successfully, and the partial clot was found inside of the pump. This case demonstrates the usefulness of serial ramp studies in patients who are suspected to have device thrombosis.
Loop Diuretic Absorption
Authors: Blake James , Devereux Richard B.
Published: September 2013

Objectives. The present study was undertaken to determine if direct blockade of angiotensin II receptors by losartan potassium as compared to ACE inhibition might result in greater tolerability in patients with congestive heart failure in whom ACE inhibition resulted in hyperkalemia and azotemia.

Background. Blockade of angiotensin II receptors by losartan potassium may produce similar benefits in congestive heart failure as ACE inhibition. However, some observations suggest losartan potassium may have different effects on renal function than ACE inhibition.

Methods. Five consecutive patients with severe congestive heart failure were identified in whom treatment with ACE inhibition was complicated by hyperkalemia (K>5.7) and azotemia. In three of these patients losartan potassium was substituted for ACE inhibition while losartan potassium was added to treatment with ACE inhibition in the remaining two. The mean of four serial values of potassium, blood urea nitrogen, and creatinine were compared before and after change in treatment using a two tailed t test.

Results. The addition or substitution of losartan potassium resulted in statistically insignificant reductions in blood urea nitrogen and creatinine and a significant reduction in potassium from 5.7±0.1 to 4.9±0.3, p<0.03. Two patients who had required kayexalate were withdrawn. In all patients, hyperkalemia resolved and did not reoccur.

Conclusions. There appear to be fundamental differences between the effects of losartan potassium and ACE inhibitors on potassium excretion in congestive heart failure patients with mild to moderate renal insufficiency. Losartan potassium may also be associated with less azotemia in such patients. These differences may have important clinical implications, particularly in the subset of patients in whom ACE inhibition is poorly tolerated as a result of hyperkalemia and azotemia.
Overseas Vietnamese in the West: The Actors and Attempts at Reconciliation
Authors: Ngọc Giao Nguyễn
Published: September 2013

Before 1975, the sociopolitical image of Vietnamese people living in the West was a reduced, deformed image of South Vietnamese society, with many overseas groups representing the whole political spectrum in South Vietnam. By the 1960s, the overseas Vietnamese community was composed mainly of students from South Vietnam, intellectuals, and exiled political leaders. In spite of the political control exercised by the Republic of Vietnam, the students became aware of the realities of the war and many organized to oppose U.S. policy. Their opposition ranged from support for the Democratic Republic of Vietnam (DRV) and the National Liberation Front, to support for the “Third Segment.” With the opening of peace negotiations in Paris in 1968, political activists from Berkeley, California, to Tokyo were rejuvenated by the reappearance of the South Vietnamese political exiles. An informal “United Front” was created to oppose General Thieu's government and to call for a coalition, as stipulated in the Paris Agreements, composed of anti‐Thieu nationalists, Buddhists, and Catholics. Opposition from Washington, D.C., to General Thieu regarding the formation of a coalition government led to the military victory of the Communist Party in 1975. The triumphalism of the Vietnamese Communist Party (VCP) and the evolution of the international situation ended hope for true reconciliation.
Epidemiological and evolutionary consequences of life‐history trade‐offs in pathogens
Authors: Laine A.‐L. , Barrès B.
Published: September 2013

Trade‐offs in life‐history traits are a central tenet in evolutionary biology, yet their ubiquity and relevance to realized fitness of populations remains questioned. Trade‐offs in pathogens are of particular interest because they may constrain the evolution and epidemiology of diseases. Here, studies that have measured life‐history trade‐offs in pathogens (fungi, oomycetes and viruses) of agricultural crops, as well as pathogens attacking wild host plants, are reviewed. The majority of studies report a penalty associated with high virulence as is evidenced by lower performance during subsequent life‐history stages. However, costs are not pervasive, and the strength and even shape of life‐history correlations can vary according to host genotype, and abiotic environment. Importantly, life‐history trade‐offs are shown to have profound epidemiological implications ranging from lower disease prevalence of strains harbouring unnecessary virulence, to increased extinction risk at the metapopulation level. From an evolutionary perspective, costs of virulence are shown to constrain the range of R genes, and hence host genotypes, a given strain can adapt to. Moreover, costs of virulence play an important role in limiting the host range of pathogens. Hence, analysis of pathogen life history plays a key role in identifying means of battling disease, from breeding durable resistance to epidemiological intervention strategies.
Effect of disease prevalence and spatial heterogeneity on polymorphism maintenance in host–parasite interactions
Authors: Moreno‐Gámez S. , Stephan W. , Tellier A.
Published: September 2013

Plants and their parasites co‐evolve at key genes of interactions following the so‐called gene‐for‐gene (GFG) relationship. Previous models of co‐evolution assume (i) single infinitely large populations of hosts and parasites and (ii) costs of resistance and infectivity. The effects of three biologically realistic characteristics of plant and parasite populations on polymorphism maintenance at GFG loci were investigated. First, two components of the cost of resistance were disentangled: the cost of harbouring the resistance allele itself, and the cost of triggering resistance when encountering a parasite. Secondly, it was assumed that plants encounter parasites depending on fixed disease prevalence in time. Thirdly, finite sizes of host and parasite populations were introduced, assuming genetic drift and mutation. In a single population, statistical polymorphism in either host or parasite can be obtained in the finite population size model if there is no cost of harbouring the resistance allele and disease prevalence is low. On the other hand, long‐term polymorphism can be maintained by heterogeneity in disease prevalence and costs of resistance in a spatially structured population with two demes linked by migration. More precisely, the trench warfare co‐evolutionary dynamics occurs when assuming large host and parasite population sizes, and large differences between demes for disease prevalence or costs of triggering resistance. Moreover, the resistance allele does not need to harbour a fitness cost in itself for long‐term stable polymorphism to occur in the co‐evolutionary models. This observation may explain the lack of empirical evidence of high costs of carrying resistance alleles.
Is this my finger? Proprioceptive illusions of body ownership and representation
Authors: Héroux Martin E. , Walsh Lee D. , Butler Annie A. , Gandevia Simon C.
Published: September 2013

Key points

The brain keeps a representation of which things are part of our body. This sense of ownership is easily manipulated using brushing of the skin or movement of a limb to create an illusion of ownership over an inanimate object, such as a rubber hand.

We induced a sense of ownership of an artificial finger using movement of the index finger without vision of the hands. As cutaneous receptors had been anaesthetised, this illusion depended on proprioceptive signals from muscle receptors.

In addition, we found a new grasp illusion in which perceived distance between the index fingers decreases when subjects hold an artificial finger.

These results increase understanding of how the brain generates our body representation and may help in understanding diseases in which the sense of ownership is disrupted.

Abstract  Body ‘ownership’ defines which things belong to us and can be manipulated by signals from cutaneous or muscle receptors. Whether signals from muscle proprioceptors on their own influence perceived ownership is unknown. We used finger‐joint movement to induce illusory ownership of an artificial finger without vision. We coupled the subject's index finger to an artificial finger 12 cm above it. The experimenter held the subject's other index finger and thumb on the artificial finger and passively moved them congruently or incongruently for 3 min with the index finger and the grasping index finger and thumb intact or anaesthetised. When intact, congruent movement (19 subjects) reduced perceived vertical distance between index fingers to 1.0 (0.0, 2.0) cm [median (IQR)] from 3.0 (3.0, 4.0) cm with incongruent movement (P < 0.01). Simply grasping the artificial finger reduced perceived spacing between the grasping and test index fingers from 6.0 (5.0, 9.0) cm to 3.0 (3.0, 6.0) cm (P < 0.01), a new grasp illusion. Digital anaesthesia eliminated this grasp effect, after which congruent movement still reduced the perceived spacing between the index fingers to 1.0 (0.0, 2.75) cm compared to 4.0 (3.25, 6.0) cm with incongruent movement (P < 0.001). Subjects more strongly agreed that they were holding their own finger after congruent but not incongruent movement (P < 0.01). We propose that the brain generates possible scenarios and tests them against available sensory information. This process can function without vision or motor commands, and with only one channel of somatic information.
Glucose utilization rates regulate intake levels of artificial sweeteners
Authors: Tellez Luis A. , Ren Xueying , Han Wenfei , Medina Sara , Ferreira Jozélia G. , Yeckel Catherine W. , de Araujo Ivan E.
Published: September 2013

Key points

Much remains to be determined regarding the physiological signals and brain systems that mediate the attribution of greater reward to sugars compared to artificial sweeteners.

We show that disruption of glucose utilization in mice produces an enduring inhibitory effect on artificial sweetener intake.

Consistently, hungry mice shifted their preferences away from artificial sweeteners and in favour of glucose after experiencing glucose in a hungry state.

Disrupting glucose oxidation suppressed dorsal striatum dopamine efflux during sugar intake.

Glucose oxidation controls intake levels of sweet tastants by modulating extracellular dopamine levels in dorsal striatum.

Abstract  It is well established that animals including humans attribute greater reinforcing value to glucose‐containing sugars compared to their non‐caloric counterparts, generally termed ‘artificial sweeteners’. However, much remains to be determined regarding the physiological signals and brain systems mediating the attribution of greater reinforcing value to sweet solutions that contain glucose. Here we show that disruption of glucose utilization in mice produces an enduring inhibitory effect on artificial sweetener intake, an effect that did not depend on sweetness perception or aversion. Indeed, such an effect was not observed in mice presented with a less palatable, yet caloric, glucose solution. Consistently, hungry mice shifted their preferences away from artificial sweeteners and in favour of glucose after experiencing glucose in a hungry state. Glucose intake was found to produce significantly greater levels of dopamine efflux compared to artificial sweetener in dorsal striatum, whereas disrupting glucose oxidation suppressed dorsal striatum dopamine efflux. Conversely, inhibiting striatal dopamine receptor signalling during glucose intake in sweet‐naïve animals resulted in reduced, artificial sweetener‐like intake of glucose during subsequent gluco‐deprivation. Our results demonstrate that glucose oxidation controls intake levels of sweet tastants by modulating extracellular dopamine levels in dorsal striatum, and suggest that glucose utilization is one critical physiological signal involved in the control of goal‐directed sweetener intake.
Applications of a New Handheld Reference Point Indentation Instrument Measuring Bone Material Strength
Authors: Randall Connor , Bridges Daniel , Guerri Roberto , Nogues Xavier , Puig Lluis , Torres Elisa , Mellibovsky Leonardo , Hoffseth Kevin , Stalbaum Tyler , Srikanth Ananya , Weaver James C. , Rosen Sasha , Barnard Heather , Brimer Davis , Proctor Alex , Candy James , Saldana Christopher , Chandrasekar Srinivasan , Lescun Timothy , Nielson Carrie M. , Orwoll Eric , Herthel Doug , Kopeikin Hal , Yang Henry T. Y. , Farr Joshua N. , McCready Louise , Khosla Sundeep , Diez-Perez Adolfo , Hansma Paul K.
Published: September 2013

A novel, hand-held Reference Point Indentation (RPI) instrument, measures how well the bone of living patients and large animals resists indentation. The results presented here are reported in terms of Bone Material Strength, which is a normalized measure of how well the bone resists indentation, and is inversely related to the indentation distance into the bone. We present examples of the instrument's use in: (1) laboratory experiments on bone, including experiments through a layer of soft tissue, (2) three human clinical trials, two ongoing in Barcelona and at the Mayo Clinic, and one completed in Portland, OR, and (3) two ongoing horse clinical trials, one at Purdue University and another at Alamo Pintado Stables in California. The instrument is capable of measuring consistent values when testing through soft tissue such as skin and periosteum, and does so handheld, an improvement over previous Reference Point Indentation instruments. Measurements conducted on horses showed reproducible results when testing the horse through tissue or on bare bone. In the human clinical trials, reasonable and consistent values were obtained, suggesting the Osteoprobe® is capable of measuring Bone Material Strength in vivo, but larger studies are needed to determine the efficacy of the instrument's use in medical diagnosis.
Articulated Manipulator With Multiple Instruments for Natural Orifice Transluminal Endoscopic Surgery
Authors: Min Seow Chi , Jian Chin Wei , Nelson Carl A. , Nakamura Akiko , Farritor Shane M. , Oleynikov Dmitry
Published: September 2013

This paper presents an articulated manipulator with multiple instruments for natural orifice endoscopic transluminal endoscopic surgery (NOTES). This robotic system is made up of four major components, namely a multifunctional manipulator, a robot-connecting arm, an articulated drive mechanism, and a surgeon control console. The manipulator, capable of changing instruments in situ at the surgical site, was developed to reduce infection risk, improve surgical workflow, and encourage solo surgery by providing surgeons with all the required instruments. The robot-connecting arm serves as an experimental platform for future bimanual robot configurations. To facilitate stable positioning and optimal orientation of the robot, the articulated drive mechanism was also created. The surgeon control console provides a user-friendly platform to receive system input from surgeons. Benchtop testing showed adequate articulation and tool-tip forces for accomplishment of typical tasks in abdominal surgery. This system leverages the benefits both of cable-wire actuation systems and of direct motor embedding on different components to achieve better tool triangulation, higher instrument grasping force, and improved positioning at the surgical site.
Magnetic Torsion Spring Mechanism for a Wireless Biopsy Capsule
Authors: Simi Massimiliano , Gerboni Giada , Menciassi Arianna , Valdastri Pietro
Published: September 2013

The authors present a novel magnetomechanical elastic element that can be loaded remotely by varying the magnetic field surrounding it and that is able to store and release mechanical energy upon external triggering. The magnetic torsion spring (MTS) is used as the core component of a self-contained miniature biopsy capsule (9 mm in diameter and 24 mm long) for random tissue sampling in the small bowel. Thanks to the MTS concept, the biopsy mechanism can be loaded wirelessly by a magnetic field applied from outside the body of the patient. At the same time, magnetic coupling guarantees stabilization against the small bowel tissue during sampling. Extreme miniaturization is possible with the proposed approach since no electronics and no power supply are required onboard.
New Distraction Osteogenesis Device With Only Two Patient-Controlled Joints by Applying the Axis-Angle Representation on Three-Dimensional Bone Deformation
Authors: Wu Ying Ying , Lucking Ryan , Oberreuter Robert , Shimada Kenji
Published: September 2013

Distraction osteogenesis is a procedure to correct bone deformity by breaking the bone and slowly pulling the fragments apart to stimulate bone growth. General bone deformities are three-dimensional in nature, requiring correcting of bone angles in 3D space and also bone length. However, commercially available external fixators are either unable to simultaneously correct for both angular and length deformity or are bulky and require as many as six joints that are adjusted by patients. In this paper, we propose a novel concept of correcting a 3D bone deformity using only two active degrees of freedom (2DOF), or two patient controlled joints, by expressing the orientation deformity of the bone using the axis-angle representation and the length discrepancy as a translation in 3D space. This requires a new device design with two patient-controlled joints, a revolute joint and a prismatic joint, that can be placed in any orientation and position to allow multiple configurations of the device. This in turn allows it to correct for all typical 3D deformities. The aim of our project is to develop the 2DOF axial external fixator and an algorithm for a planner to find the optimal fixator configuration and the correction schedule for a given deformity. An algorithm for the placement of the two patient-controlled joints relative to the osteotomy site was developed. A set of test data extracted from a deformed sawbone was used to check the performance of the proposed computational method. The desired bone trajectory was defined as a straight line from initial to target position, and the optimal position of the revolute joint gives an error of only 0.8 mm. We conclude that the proposed 2DOF device and the computational planner can correct typical bone deformity and works well for the test case in simulation.
Structural Change Quantification in Rotor Systems Based on Measured Resonance and Antiresonance Frequencies
Authors: Wroblewski Adam C. , Pesch Alexander H. , Sawicki Jerzy T.
Published: September 2013

A structural change quantification methodology is proposed in which the magnitude and location of a structural alteration is identified experimentally in a rotor system. The resonance and antiresonance frequencies are captured from multiple frequency response functions and are compared with baseline data to extract frequency shifts due to these features. The resulting expression contains sufficient information to identify the dynamic characteristics of the rotor in both the frequency and spatial domains. A finite element model with carefully selected tunable parameters is iteratively adjusted using a numerical optimization algorithm to determine the source of the structural change. The methodology is experimentally demonstrated on a test rig with a laterally damaged rotor and the frequency response functions are acquired through utilization of magnetic actuators positioned near the ball bearings.
Design of High Speed Rotary Valves for Pneumatic Applications
Authors: Brown Travis L. , Atluri Prasad , Schmiedeler James P.
Published: September 2013

Valves based on rotating geometry have long been sought by designers for their simplicity, compactness, and desirable dynamic properties. Unfortunately, they generally involve tight sealing surfaces with significant relative motion, making them particularly prone to problems of wear, leakage, and seizure. These inherent weaknesses are easily overcome in applications involving low pressures or low actuation speeds but become more significant in applications with high pressures and/or high speeds. In this paper, a new high speed, high pressure rotary valve design for an experimental reciprocating compressor-expander is presented. A physical prototype is created, and leakage and valving experiments are performed. Sealing performance is verified and shown to be on the order of piston ring leakage, making it suitable for compressor use. Although not intended for combustion applications, it is possible that a modified version of this design could function in that capacity. As shown, this design is useful in pneumatic applications in which temperatures are lower and oil leakage is tolerable.
Modeling and Estimation of Unmeasured Variables in a Wastegate Operated Turbocharger
Authors: Salehi Rasoul , Vossoughi Gholamreza , Alasty Aria
Published: September 2013

Estimation of relevant turbocharger variables is crucial for proper operation and monitoring of turbocharged (TC) engines, which are important in improving fuel economy of vehicles. This paper presents mean-value models developed for estimating gas flow over the turbine and the wastegate (WG), the wastegate position, and the compressor speed in a TC gasoline engine. The turbine is modeled by an isentropic nozzle with a constant area and an effective pressure ratio calculated from the turbine upstream and downstream pressures. Another physically sensible model is developed for estimating either the WG flow or position. Provided the WG position is available, the WG flow is estimated using the orifice model for compressible fluids. The WG position is predicted considering forces from the WG passing flow and actuator. Moreover, a model for estimating the compressor speed in low and medium compressor pressure ratios is proposed, using the compressor head and efficiency modified by the turbine effective pressure ratio. The estimates of the turbocharger variables match well with the experimentally measured data. The three proposed models are simple in structure, accurate enough to be utilized for engine modeling, and suitable to be validated and calibrated on an internal combustion engine in a test cell.
A Study on Gas–Liquid Film Thicknesses and Heat Transfer Characteristics of Vapor–Gas Condensation Outside a Horizontal Tube
Authors: Li Huijun , Peng Wenping
Published: September 2013

Noncondensable gases deteriorate heat transfer in the condensation process. It is therefore necessary to study vapor–gas condensation heat transfer process and analyze main factors influencing the process. Based on the double-film theory and the Prandtl boundary layer theory, this investigation developed a mathematical model of gas–liquid film thicknesses and local heat transfer coefficient for studying laminar film condensation in the presence of noncondensable gas over a horizontal tube. Induced velocity in the gas film, gas–liquid interfacial shear stress, and pressure gradient were considered in the study. Importantly, gas–liquid film separations were analyzed in depth in this paper. It obtained the distributions of gas–liquid film thicknesses, local heat transfer coefficient, condensate mass flux, and gas–liquid interfacial temperature along the tube surface, and analyzed the influences of bulk velocity, total pressure, bulk mass concentration of noncondensable gas and wall temperature on them, providing a theoretical guidance for understanding and enhancing vapor–gas condensation heat transfer. Gas film thickness and gas–liquid film separations have certain effects on vapor–gas condensation heat transfer. The average dimensionless heat transfer coefficients are in agreement with the data from related literatures.