939 research outputs found

    The role of the exit in the initial screening of investment opportunities: The case of business angel syndicate gatekeepers

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    The exit process has been largely ignored in business angel research.. The practitioner community identifies the difficulty in achieving exits as the most pressing problem for investors. This has been attributed to the failure of investors to adopt an exit-centric approach to investing. The validity of this claim is examined via a study of the investment approach of 21 ‘gatekeepers’ (managers) of angel groups in Scotland and Northern Ireland. Most gatekeepers say that they do consider the exit when they invest. However, this is contradicted by a verbal protocol analysis which indicates that the exit is not a significant consideration in their initial screening process. The small number of exits achieved by the groups is consistent with the general lack of an exit-centric approach to investing. Only three groups exhibit evidence of a strong exit-centric approach to investing. The lack of exits may have a negative impact on the level of future angel investment activity

    Why business angels reject investment opportunities: Is it personal?

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    A major focus of research on business angels has examined their decision-making processes and investment criteria. As business angels reject most of the opportunities that they receive, this article explores the reasons informing such decisions. In view of angel heterogeneity, investment opportunities might be expected to be rejected for differing reasons. Two sources of data are used to examine this issue. Face-to-face interviews with 30 business angels in Scotland and Northern Ireland provided information on typical ‘deal killers’. This was complemented by an Internet survey of United Kingdom that attracted responses from 238 UK business angels. The findings confirm that the main reason for rejection relates to the entrepreneur/management team. However, angel characteristics do not explain the number of reasons given for opportunity rejection nor do they predict the reasons for rejecting investment opportunities. This could be related to the increasing trend for business angels to join organised groups which, in turn, leads to the development of a shared repertoire of investment approaches. We suggest the concept of ‘communities-of-practice’ as an explanation for this finding

    Frontal mucocele with an accompanying orbital abscess mimicking a fronto-orbital mucocele: case report

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    BACKGROUND: Mucoceles are slowly expanding cystic lesions with respiratory epithelium containing mucus most commonly affecting the frontal and ethmoidal sinuses. They are caused by obstruction of sinus ostium. Mucoceles exert pressure on the bony boundaries and due to the proximity to the brain and orbit extension to these areas are common. CASE PRESENTATION: A case of a frontal mucocele with an accompanying orbital abscess mimicking a fronto-orbital mucocele is reported. A 77 year old female patient suffering from left sided proptosis and pain around the left eye was admitted to our department. She had a history of left frontal sinus mucocele one year ago that was offered an osteoplastic frontal sinus surgery that the patient refused. Patient had limitation of eye movements. Fundoscopic examination revealed a minimal papilledema. Coronal computerized tomography and orbital magnetic resonance imaging showed a frontal mucocele with suspicious erosion of the orbital roof and a superiorly localized extraconal mass displacing the orbit lateroinferiorly. Frontal and orbital masses had similar intensities. Thus surgery was planned for a fronto-orbital mucocele. During surgery no defect was found on the orbital roof. Frontal mucocele and orbital cystic mass was removed separately. Pathological examination showed a frontal mucocele and an orbital abscess wall. Postoperatively eye movements returned to normal and papilledema resolved. CONCLUSION: Fronto-orbital mucoceles are commonly encountered pathologies, but frontal mucocele with an orbital abscess is a rarely seen and should be kept in mind because their treatments differ

    Conscious monitoring and control (reinvestment) in surgical performance under pressure.

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    Research on intraoperative stressors has focused on external factors without considering individual differences in the ability to cope with stress. One individual difference that is implicated in adverse effects of stress on performance is "reinvestment," the propensity for conscious monitoring and control of movements. The aim of this study was to examine the impact of reinvestment on laparoscopic performance under time pressure

    Developing a dynamic digital twin at a building level: Using Cambridge campus as case study

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    A Digital Twin (DT) refers to a digital replica of physical assets, processes and systems. DTs integrate artificial intelligence, machine learning and data analytics to create dynamic digital models that are able to learn and update the status of the physical counterpart from multiple sources. A DT, if equipped with appropriate algorithms will represent and predict future condition and performance of their physical counterparts. Current developments related to DTs are still at an early stage with respect to buildings and other infrastructure assets. Most of these developments focus on the architectural and engineering/construction point of view. Less attention has been paid to the operation & maintenance (O&M) phase, where the value potential is immense. A systematic and clear architecture verified with practical use cases for constructing a DT is the foremost step for effective operation and maintenance of assets. This paper presents a system architecture for developing dynamic DTs in building levels for integrating heterogeneous data sources, support intelligent data query, and provide smarter decision-making processes. This will further bridge the gaps between human relationships with buildings/regions via a more intelligent, visual and sustainable channels. This architecture is brought to life through the development of a dynamic DT demonstrator of the West Cambridge site of the University of Cambridge. Specifically, this demonstrator integrates an as-is multi-layered IFC Building Information Model (BIM), building management system data, space management data, real-time Internet of Things (IoT)-based sensor data, asset registry data, and an asset tagging platform. The demonstrator also includes two applications: (1) improving asset maintenance and asset tracking using Augmented Reality (AR); and (2) equipment failure prediction. The long-term goals of this demonstrator are also discussed in this paper

    Structural diversity of biologically interesting datasets: a scaffold analysis approach

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    ABSTRACT:The recent public availability of the human metabolome and natural product datasets has revitalized "metabolite-likeness" and "natural product-likeness" as a drug design concept to design lead libraries targeting specific pathways. Many reports have analyzed the physicochemical property space of biologically important datasets, with only a few comprehensively characterizing the scaffold diversity in public datasets of biological interest. With large collections of high quality public data currently available, we carried out a comparative analysis of current day leads with other biologically relevant datasets.In this study, we note a two-fold enrichment of metabolite scaffolds in drug dataset (42%) as compared to currently used lead libraries (23%). We also note that only a small percentage (5%) of natural product scaffolds space is shared by the lead dataset. We have identified specific scaffolds that are present in metabolites and natural products, with close counterparts in the drugs, but are missing in the lead dataset. To determine the distribution of compounds in physicochemical property space we analyzed the molecular polar surface area, the molecular solubility, the number of rings and the number of rotatable bonds in addition to four well-known Lipinski properties. Here, we note that, with only few exceptions, most of the drugs follow Lipinski's rule. The average values of the molecular polar surface area and the molecular solubility in metabolites is the highest while the number of rings is the lowest. In addition, we note that natural products contain the maximum number of rings and the rotatable bonds than any other dataset under consideration.Currently used lead libraries make little use of the metabolites and natural products scaffold space. We believe that metabolites and natural products are recognized by at least one protein in the biosphere therefore, sampling the fragment and scaffold space of these compounds, along with the knowledge of distribution in physicochemical property space, can result in better lead libraries. Hence, we recommend the greater use of metabolites and natural products while designing lead libraries. Nevertheless, metabolites have a limited distribution in chemical space that limits the usage of metabolites in library design.14 page(s

    Development and Validation of a Surgical Workload Measure: The Surgery Task Load Index (SURG-TLX)

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    Background: The purpose of the present study was to develop and validate a multidimensional, surgery-specific workload measure (the SURG-TLX), and to determine its utility in providing diagnostic information about the impact of various sources of stress on the perceived demands of trained surgical operators. As a wide range of stressors have been identified for surgeons in the operating room, the current approach of considering stress as a unidimensional construct may not only limit the degree to which underlying mechanisms may be understood but also the degree to which training interventions may be successfully matched to particular sources of stress. Methods: The dimensions of the SURG-TLX were based on two current multidimensional workload measures and developed via focus group discussion. The six dimensions were defined as mental demands, physical demands, temporal demands, task complexity, situational stress, and distractions. Thirty novices were trained on the Fundamentals of Laparoscopic Surgery (FLS) peg transfer task and then completed the task under various conditions designed to manipulate the degree and source of stress experienced: task novelty, physical fatigue, time pressure, evaluation apprehension, multitasking, and distraction. Results: The results were supportive of the discriminant sensitivity of the SURG-TLX to different sources of stress. The sub-factors loaded on the relevant stressors as hypothesized, although the evaluation pressure manipulation was not strong enough to cause a significant rise in situational stress. Conclusions: The present study provides support for the validity of the SURG-TLX instrument and also highlights the importance of considering how different stressors may load surgeons. Implications for categorizing the difficulty of certain procedures, the implementation of new technology in the operating room (man-machine interface issues), and the targeting of stress training strategies to the sources of demand are discussed. Modifications to the scale to enhance clinical utility are also suggested. © 2011 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201

    Multitask training promotes automaticity of a fundamental laparoscopic skill without compromising the rate of skill learning.

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    A defining characteristic of expertise is automated performance of skills, which frees attentional capacity to better cope with some common intraoperative stressors. There is a paucity of research on how best to foster automated performance by surgical trainees. This study examined the use of a multitask training approach to promote automated, robust laparoscopic skills.Eighty-one medical students completed training of a fundamental laparoscopic task in either a traditional single-task training condition or a novel multitask training condition. Following training, participants' laparoscopic performance was tested in a retention test, two stress transfer tests (distraction and time pressure) and a secondary task test, which was included to evaluate automaticity of performance. The laparoscopic task was also performed as part of a formal clinical examination (OSCE).The training groups did not differ in the number of trials required to reach task proficiency (p = .72), retention of skill (ps > .45), or performance in the clinical examination (p = .14); however, the groups did differ with respect to the secondary task (p = .016). The movement efficiency (number of hand movements) of single-task trainees, but not multitask trainees, was negatively affected during the secondary task test. The two stress transfer tests had no discernable impact on the performance of either training group.Multitask training was not detrimental to the rate of learning of a fundamental laparoscopic skill and added value by providing resilience in the face of a secondary task load, indicative of skill automaticity. Further work is needed to determine the extent of the clinical utility afforded by multitask training

    Effects of dopamine D2/D3 receptor antagonism on human planning and spatial working memory

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    Psychopharmacological studies in humans suggest important roles for dopamine (DA) D2 receptors in human executive functions, such as cognitive planning and spatial working memory (SWM). However, studies that investigate an impairment of such functions using the selective DA D2/3 receptor antagonist sulpiride have yielded inconsistent results, perhaps because relatively low doses were used. We believe we report for the first time, the effects of a higher (800 mg p.o.) single dose of sulpiride as well as of genetic variation in the DA receptor D2 gene (DA receptor D2 Taq1A polymorphism), on planning and working memory. With 78 healthy male volunteers, we apply a between-groups, placebo-controlled design. We measure outcomes in the difficult versions of the Cambridge Neuropsychological Test Automated Battery One-Touch Stockings of Cambridge and the self-ordered SWM task. Volunteers in the sulpiride group showed significant impairments in planning accuracy and, for the more difficult problems, in SWM. Sulpiride administration speeded response latencies in the planning task on the most difficult problems. Volunteers with at least one copy of the minor allele (A1+) of the DA receptor D2 Taq1A polymorphism showed better SWM capacity, regardless of whether they received sulpiride or placebo. There were no effects on blood pressure, heart rate or subjective sedation. In sum, a higher single dose of sulpiride impairs SWM and executive planning functions, in a manner independent of the DA receptor D2 Taq1A polymorphism.This research work was funded by a Core Award from the Medical Research Council and the Wellcome Trust to the Behavioural and Clinical Neuroscience Institute (MRC Ref G1000183; WT Ref 093875/Z/10/Z). Also supported by a Wellcome Trust Senior Investigator Award (104631/Z/14/Z) awarded to TWR. CE was supported by the Swiss National Science Foundation (PA00P1_134135) and the Vienna Science and Technology Fund (WWTF VRG13-007)
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