1,373 research outputs found
Entrepreneurial intentions among students: towards a re-focused research agenda
Purpose â This paper aims to address the need for a re-focused research agenda in relation to graduate entrepreneurship. An important theme for some years has been the effort to monitor attitudes and intentions of students towards starting up their own businesses. It is timely, however, to raise some questions about both the impact of this research and likewise the general approach it has taken in understanding the phenomenon of graduate entrepreneurship. Design/methodology/approach â The paper draws on a large data set (over 8,000 students) from one UK region. Specifically, it presents data from the 2007/2008 Entrepreneurial Intentions (EI) survey within the Yorkshire and Humberside region and reflects back over previous iterations of this research. Findings â The paper identifies three key outcomes. First, it establishes that across all years of the survey a substantial minority of students consistently hold relatively strong start-up intentions. Second, the paper highlights that, despite considerable efforts to increase the numbers moving to start-up, little impact is discernible. Third, the paper suggests that, although the EI survey is useful as a stock-taking exercise, it fails to address critical questions around the impact of higher education on entrepreneurship and the transition from entrepreneurial intent to the act of venture creation. Originality/value â The paper provides an important positioning perspective on the relationship between higher education and graduate entrepreneurship. While highlighting the importance of the EI research, the paper establishes the need for a re-focused research agenda; one that is conceptually robust and with a focus on the student journey from higher education to graduate entrepreneur
A Computational Study of Cooling Via Ultrasound Enhanced Heat Transfer of Acoustically Driven Flows
Previous work has shown that acoustic streaming improves heat transfer via enhanced fluid mixing. A fluid undergoing ultrasonic propagation is seen to exhibit distinctive circulatory flow structures that encourage thermal boundary layer dispersion of any given heat source. The work is found to be essential for enhanced cooling in applications such as microelectronics where the use of thermoacoustic engines can be used to continually provide a cooled environment though enhanced heat transfer. Computational Fluid Dynamics can provide an in-depth understanding of the flow structures and resulting behaviours for a fluid undergoing acoustic streaming. A computational procedure has been developed to simulate the acoustic effects of a given fluid from a 2nd-order solution. The model was found to produce results that formed a good approximation to the experimentation, built upon a base convection model whose mesh was validated using a previous experiment to observe thermal boundary layer behavior. A detailed frequency study on the effects of fluid structure and development was modeled in a given geometry. A study was conducted on the mechanisms behind the flow development between each incremental rise in frequency. It was found that a change was induced between the number of circulatory loops in each configuration along with a cut-off point in frequency magnitude beyond which the circulation was found to concentrate around the acoustic source. Insight into the degree of dynamic stability was gained through modelling the fluid through one wave period where it was found that the model was able to resolve the expansive and contractive behavior of a boundary layer through one wave period. The results were also able to visualise the cooling mechanisms by resolving the temperature distribution across the entire period. The effects of geometry on heat transfer were studied to ascertain an optimum configuration where enhanced heat transfer was seen to be at its greatest for the given domain. A detailed study of geometry height was conducted to investigate the changes in loop formulation and the consequential effect on heat transfer. Heat transfer was found to correlate with flow structure stability in which two distinctive counter rotating loops resulted in an increase disruption to the thermal boundary layer. This was found to happen in the medium position of the height range
Gamow-Teller transitions and deformation in the proton-neutron random phase approximation
We investigate reliability of Gamow-Teller transition strengths computed in
the proton-neutron random phase approximation, comparing with exact results
from diagonalization in full shell-model spaces. By allowing the
Hartree-Fock state to be deformed, we obtain good results for a wide variety of
nuclides, even though we do not project onto good angular momentum. We suggest
that deformation is as important or more so than pairing for Gamow-Teller
transitions.Comment: 8 pages, 5 figures; added references, clarified discussion with
regards to stabilit
Bowel dysfunction after transposition of intestinal segments into the urinary tract : 8-year prospective cohort study
Purpose Bowel function may be disturbed after intestinal segments are transposed into the urinary tract to reconstruct or replace the bladder. In 1997, our group were the first to report major bowel dysfunction in a cohort of such patients: up to 42% of those who were asymptomatic preoperatively describing new bowel symptoms postoperatively including explosive diarrhoea, nocturnal diarrhoea, faecal urgency, faecal incontinence and flatus leakage . We now describe bowel symptoms in this same cohort eight years later (2005). Materials and Methods 116 patients were evaluable. Of the remaining 37 from the original report: 30 had died, five no longer wished to be involved, and two could not be traced. Patients were asked to complete postal questionnaires identical to those used in the first follow-up, assessing the severity of bowel symptoms and quality of life using two validated instruments. Responses were compared with those from the original study. The Nottingham Health Profile quality of life scores were also compared to age and sex matched norms. Results 96 (83%) completed eight-year follow-up questionnaires: 43 after ileal conduit diversion (Group 1), 17 after clam enterocystoplasty for overactive bladder (Group 2), 18 after reconstructed bladder for neurogenic bladder dysfunction (Group 3), and 18 with bladder replacement for non-neurogenic causes (Group 4). High prevalence rates of bowel symptoms persisted with no statistically significant differences between the two time points. Of those with symptoms in 2005, around 50% had reported similar symptoms in 1997. Clam enterocystoplasty patients (Group 2) still reported the highest prevalence (59%) of troublesome diarrhoea with one in two on regular anti-diarrhoeal medication. They also had high rates of faecal incontinence (47%), faecal urgency (41%) and nocturnal bowel movement (18%); with high proportions reporting a moderate or severe adverse effect on work (36%), social life (50%) and sex life (43%). High rates were also reported by neurogenic bladder dysfunction patients, including 50% with troublesome diarrhoea. This symptom was reported by 19% after ileal conduit and by 17% after bladder replacement for non-neurogenic causes. The impact of bowel symptoms on every-day activities and quality of life persisted, remaining most severe after clam enterocystoplasty, with 24% regretting undergoing the procedure because of subsequent bowel symptoms. Conclusions: After more than eight years, operations involving transposition of intestinal segments continue to be associated with high rates of bowel symptoms, which impact on everyday activities. These are particularly troublesome following enterocystoplasty for overactive bladder and bladder reconstruction for neurogenic bladder dysfunction. These risks should influence patient selection and potential patients should be warned prior to surgery
A unified SLAM solution using partial 3D structure
Good quality of environment mapping demands modelling the associated environment nearly to its 3D originality. This paper presents a unified Simultaneous Localisation And Mapping (SLAM) solution based on partial 3D structure. As compared to existing representations such as grid based mapping, the novelty of the proposed unified approach lies in estimation, representation and handling of compact partial 3D features-based map model for a team of robots that are working in an unknown environment with unknown poses. The approach replies on a camera to perceive the environment and a 2D laser sensor to generate a SLAM solution with partial 3D features based representation. Extended Kalman Filter (EKF) estimates the robot pose based on its motion model and map of the explored environment. The solution has been tested in an indoor environment on two identical custom-developed robots. Experimental results have demonstrated efficacy of the approach. The presented solution can be easily applied on a distributed/centralized robotic system with ease of data handling and reduced computational cost
Bowel dysfunction after transposition of intestinal segments into the urinary tract : 8-year prospective cohort study
Purpose Bowel function may be disturbed after intestinal segments are transposed into the urinary tract to reconstruct or replace the bladder. In 1997, our group were the first to report major bowel dysfunction in a cohort of such patients: up to 42% of those who were asymptomatic preoperatively describing new bowel symptoms postoperatively including explosive diarrhoea, nocturnal diarrhoea, faecal urgency, faecal incontinence and flatus leakage . We now describe bowel symptoms in this same cohort eight years later (2005). Materials and Methods 116 patients were evaluable. Of the remaining 37 from the original report: 30 had died, five no longer wished to be involved, and two could not be traced. Patients were asked to complete postal questionnaires identical to those used in the first follow-up, assessing the severity of bowel symptoms and quality of life using two validated instruments. Responses were compared with those from the original study. The Nottingham Health Profile quality of life scores were also compared to age and sex matched norms. Results 96 (83%) completed eight-year follow-up questionnaires: 43 after ileal conduit diversion (Group 1), 17 after clam enterocystoplasty for overactive bladder (Group 2), 18 after reconstructed bladder for neurogenic bladder dysfunction (Group 3), and 18 with bladder replacement for non-neurogenic causes (Group 4). High prevalence rates of bowel symptoms persisted with no statistically significant differences between the two time points. Of those with symptoms in 2005, around 50% had reported similar symptoms in 1997. Clam enterocystoplasty patients (Group 2) still reported the highest prevalence (59%) of troublesome diarrhoea with one in two on regular anti-diarrhoeal medication. They also had high rates of faecal incontinence (47%), faecal urgency (41%) and nocturnal bowel movement (18%); with high proportions reporting a moderate or severe adverse effect on work (36%), social life (50%) and sex life (43%). High rates were also reported by neurogenic bladder dysfunction patients, including 50% with troublesome diarrhoea. This symptom was reported by 19% after ileal conduit and by 17% after bladder replacement for non-neurogenic causes. The impact of bowel symptoms on every-day activities and quality of life persisted, remaining most severe after clam enterocystoplasty, with 24% regretting undergoing the procedure because of subsequent bowel symptoms. Conclusions: After more than eight years, operations involving transposition of intestinal segments continue to be associated with high rates of bowel symptoms, which impact on everyday activities. These are particularly troublesome following enterocystoplasty for overactive bladder and bladder reconstruction for neurogenic bladder dysfunction. These risks should influence patient selection and potential patients should be warned prior to surgery
Mendelian randomization case-control PheWAS in UK Biobank shows evidence of causality for smoking intensity in 28 distinct clinical conditions.
Background: Smoking is one of the greatest threats to public health worldwide. We integrated phenome-wide association study (PheWAS) and Mendelian randomization (MR) approaches to explore causal effects of genetically predicted smoking intensity across the human disease spectrum. Methods: We conducted PheWAS case-control analyses in 152,483 ever smokers of White-British ancestry, aged 39-73 years. Disease diagnoses were based on hospital inpatient and mortality registrations. Smoking intensity was instrumented by four genetic variants, and disease risks estimated for one cigarette per day heavier intakes. Associations passing the FDR threshold (p<0âą0025) were assessed for causality using several complementary MR approaches. Findings: Genetically instrumented smoking intensity was associated with 48 conditions, with MR supporting a possible causal effect for 28 distinct outcomes. Each cigarette smoked per day elevated the odds of respiratory diseases by 5% to 33% (nine distinct diseases, including pneumonia, emphysema, obstructive chronic bronchitis, pleurisy, pulmonary collapse, respiratory failure) and the odds of circulatory disease by 5% to 23% (seven diseases, including atherosclerosis, myocardial infarction, congestive heart failure, arterial embolisms). Further effects were seen for cancer within the respiratory system and other neoplasms, renal failure, septicaemia, and retinal disorders. No associations were observed in sensitivity analyses on 185,002 never smokers. Interpretation: These genetic data demonstrate the substantial adverse health impacts by smoking intensity and suggest notable increases in the risks of several diseases. Public health initiatives should highlight the damage caused by smoking intensity and the potential benefits of reducing or ideally quitting smoking
Assessment of academic departments efficiency using data envelopment analysis
Purpose:
In this age of knowledge economy, universities play an important role in the development of a country. As government subsidies to universities have been decreasing, more efficient use of resources becomes important for university administrators. This study evaluates the relative technical efficiencies of academic departments at the Islamic University in Gaza (IUG) during the years 2004-2006.
Design/methodology/approach:
This study applies Data Envelopment Analysis (DEA) to assess the relative technical efficiency of the academic departments. The inputs are operating expenses, credit hours and training resources, while the outputs are number of graduates, promotions and public service activities. The potential improvements and super efficiency are computed for inefficient and efficient departments respectively. Further, multiple linear -regression is used to develop a relationship between super efficiency and input and output variables.
Findings:
Results show that the average efficiency score is 68.5% and that there are 10 efficient departments out of the 30 studied. It is noted that departments in the faculty of science, engineering and information technology have to greatly reduce their laboratory expenses. The department of economics and finance was found to have the highest super efficiency score among the efficient departments. Finally, it was found that promotions have the greatest contribution to the super efficiency scores while public services activities come next.
Research limitations/implications:
The paper focuses only on academic departments at a single university. Further, DEA is deterministic in nature
Interface magnetism in Fe2O3/FeTiO3-heterostructures
To resolve the microscopic origin of magnetism in the Fe2O3/FeTiO3-system, we
have performed density functional theory calculations taking into account
on-site Coulomb repulsion. By varying systematically the concentration,
distribution and charge state of Ti in a hematite host, we compile a phase
diagram of the stability with respect to the end members and find a clear
preference to form layered arrangements as opposed to solid solutions. The
charge mismatch at the interface is accommodated through Ti4+ and a
disproportionation in the Fe contact layer into Fe2+, Fe3+, leading to
uncompensated moments in the contact layer and giving first theoretical
evidence for the lamellar magnetism hypothesis. This interface magnetism is
associated with impurity levels in the band gap showing halfmetallic behavior
and making Fe2O3/FeTiO3 heterostructures prospective materials for spintronics
applications.Comment: 4 pages, 3 figure
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