bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of Image Quality in Real Time Three‐Dimensional Dobutamine Stress Echocardiography: An Integrated 2D/3D Approach
Authors: Johri Amer M. , Chitty David W. , Hua Lanqi , Marincheva Gergana , Picard Michael H. 
Published: July 2014

BackgroundThree‐dimensional (3D) stress echocardiography is a relatively new technique offering the potential to acquire images of the entire left ventricle from 1 or 2 transducer positions in a time‐efficient manner. Relative to two‐dimensional (2D) imaging, the ability to quickly acquire full volume images during peak stress with 3D echocardiography can eliminate left ventricular (LV) foreshortening while reducing inter‐operator variability. Our objectives were to (1) determine the practicality of a novel integrated 2D/3D stress protocol in incorporating 3D imaging into a standard 2D stress echocardiogram and (2) to determine whether the quality of imaging using the novel 2D/3D protocol was sufficient for interpretation.MethodsTwenty‐five patients referred for stress echocardiography underwent an integrated 2D/3D image acquisition protocol. LV segments were scored from 0 (absent or no clear endocardial visualization) to 3 (excellent/full visualization of endocardial border) with each modality. 2D segment quality scoring was compared with 3D. An integrated score was compared with either 2D or 3D imaging alone.ResultsTwo‐dimensional and 3D imaging were optimal for differing segments and the integrated protocol was superior to either modality alone. 3D imaging was superior in visualizing the anterior and anterolateral region of the base segments, compared to 2D imaging. 3D imaging was less useful for the base, the mid‐inferior, and the inferoseptal segments, thus emphasizing the need to retain 2D imaging in stress echocardiography at this time.ConclusionThe integrated 2D/3D protocol approach to stress echocardiography is technically feasible and maximizes image quality of dobutamine stress echocardiography, improving patient assessment.
Two‐Dimensional Strain and Strain Rate Imaging of the Left Atrium and Left Ventricle in Adult Patients with Atrial Septal Defects before and after the Later Stage of Percutaneous Device Closure
Authors: Cakal Sinem , Eroglu Elif , Baydar Onur , Cakal Beytullah , Yazicioglu Mehmet Vefik , Bulut Mustafa , Dundar Cihan , Tigen Kursat , Ozkan Birol , Acar Goksel , Avci Anil , Esen Ali Metin 
Published: July 2014

AimAtrial septal defect (ASD) causes chronic volume overload of the right heart. The potential adverse effects of this long‐standing volume overload to left atrium (LA) and left ventricle (LV) and their response to ASD closure has been poorly studied.MethodsWe studied 20 ASD patients before the procedure, at the 24‐hour and 1 month following the percutaneous closure. Twenty age‐matched controls served as the control group. The analysis for atrial deformation was performed on the lateral wall, mid segment of the LA from apical four‐chamber view. Peak longitudinal strain (S) and strain rate (SR) during LA reservoir, passive emptying, atrial contraction phases and LV global longitudinal systolic S and SR were measured.ResultsPeak S and SR at LA reservoir, conduit and late contraction phases in ASD patients were similar to controls. All of these parameters increased immediately after the closure of the defect. Similarly, SLV and SRLV in ASD patients were not significantly different from the controls and significantly increased after the closure. But LA S, SR and LV S, SR results decreased in 1 month after the closure. SLV in ASD patients was significantly correlated with echocardiographic findings and the invasively measured defect size.ConclusionLA and LV S and SR are not significantly affected in ASD patients. However, correction of the long‐standing volume overload by percutaneous closure causes an early increase in LA and LV longitudinal deformation that correlates with the magnitude of the atrial septal defect. But this increase decreased in 1 month after closure.
The clinical utility of botulinum toxin injections targeted at the motor endplate zone in cervical dystonia
Authors: Delnooz C. C. S. , Veugen L. C. , Pasman J. W. , Lapatki B. G. , van Dijk J. P. , van de Warrenburg B. P. C. 
Published: July 2014

Background and purposeCervical dystonia (CD) patients usually receive repeated botulinum neurotoxin (BoNT) injections. The aims of this study were to evaluate the feasibility of motor endplate zone (MEZ) detection of relevant cervical muscles in CD patients receiving chronic BoNT treatment and to compare the treatment effect of half‐dosed, endplate‐targeted injections to standard BoNT injections.MethodsIn study 1, high‐density surface electromyography (HD‐sEMG) was recorded from the sternocleidomastoid (SCM) and splenius capitis (SC) muscles in 18 CD patients with ongoing BoNT treatment, by which the location of the MEZ was determined. In study 2, nine additional patients with rotational‐type CD participated in a treatment effect study where they received either half of their regular BoNT dose through endplate‐targeted injections or their normal BoNT dose through standard injections (crossover design). Dystonia severity was recorded before and 4 weeks after each treatment session (Toronto Western Spasmodic Torticollis Rating Scale severity subscore).ResultsIn the SCM muscle the MEZ was located at the lower border of the superior third part of the muscle, and in the SC muscle at half muscle length. Endplate‐targeted, half‐dosed BoNT injection resulted in a similar treatment effect to injecting the full dose in the standard technique.ConclusionsHalf‐dosed, endplate‐targeted BoNT injections lead to a similar treatment effect to the standard BoNT injection protocol. MEZ detection confronts the clinician with some technical challenges, such as the ability of accurate and technically optimal placement of the electrode grid and correct interpretation of the HD‐sEMG signal.
Improved mapping of interictal epileptiform discharges with EEG‐fMRI and voxel‐wise functional connectivity analysis
Authors: Liu Junjie V. , Kobylarz Erik J. , Darcey Terrance M. , Lu Zhengang , Wu Yu‐Chien , Meng Ming , Jobst Barbara C. 
Published: July 2014

SummaryObjectiveWe describe a novel method to spatially map interictal epileptiform discharges (IEDs) through voxel‐wise functional connectivity analysis of the functional magnetic resonance imaging (fMRI) portion of simultaneous electroencephalography (EEG)–fMRI data. This method measures the local synchronicity of fMRI signals associated with IED and, in contrast to conventional methods, does not require modeling of neural activities or hemodynamic response.MethodsSimultaneous EEG‐fMRI was performed on six patients with focal epilepsy. IED events were detected from the EEG data. The fMRI data was subdivided into time segments of 20 s in length, and then reorganized into one set of concatenated time series containing the IED events and many sets without IEDs. Local degree centrality (LDC), a metric of functional connectivity, was computed for each brain voxel to summarize its signal correlations to brain voxels within 14 mm of physical distance. This computation was repeated for each set of concatenated time series, yielding one whole‐brain LDC map for time with the IED events and many maps for time without IED. A statistical score was computed for each voxel to detect the voxels with significant LDC value differences associated with IEDs. The fMRI data were also processed separately by conventional methods for comparison.ResultsIn all six patients, regions with significant LDC increase during IEDs were concordant in location to both simultaneous EEG and the epileptogenic focus determined from separate clinical studies. In contrast, results from the conventional methods were concordant in only three patients.SignificanceWe show that for focal epilepsy, voxel‐wise functional connectivity analysis of EEG‐fMRI data may improve IED localization and EEG concordance compared to the conventional analysis. This new analytic method may improve the robustness of interictal EEG‐fMRI as a technique for mapping the epileptogenic focus, and helps study the local synchronization aspect of the epileptic network.
Knowledge‐related challenges and solutions in GSD
Authors: Parviainen Päivi , Tihinen Maarit 
Published: July 2014

AbstractA number knowledge‐related challenges may complicate the work in global software development (GSD) projects. In practice, even a small amount of missing knowledge may cause an activity to fail to create and transfer information which is critical to later functions, causing these later functions to fail. Thus, knowledge engineering holds a central role in order to succeed with globally distributed product development. Furthermore, examining the challenges faced in GSD from a cognitive perspective will help to find solutions that take into account the knowledge needs of different stakeholders in GSD and thus help to establish conditions for successful GSD projects. In this paper, we will discuss these challenges and solutions based on an extensive literature study and practical experience gained in several international projects over the last decade. Altogether, over 50 case studies were analysed. We analysed the challenges identified in the cases from a cognitive perspective for bridging and avoiding the knowledge gaps and, based on this analysis, we will present example solutions to address the challenges during the GSD projects. We will conclude that through understanding both the nature of GSD and the KE challenges in depth, it will be possible for organizations to make their distributed operations successful.
The Riskiness of Public Sector Performance Measurement: A Review and Research Agenda
Authors: Cuganesan Suresh , Guthrie James , Vranic Vedran 
Published: July 2014

AbstractPublic sector performance measurement (PM) practices can be risky. It is imperative that research engages with the riskiness of PM and how this might be reduced. To help move towards a less risky state of public sector PM, where benefits outweigh negative potential, this paper reviews studies on PM risk to ascertain what existing research indicates about (a) the risks of PM (b) the conditions in which the risks of PM are more likely to manifest, and (c) the approaches that mitigate the risks of PM. Based on this, the paper outlines a way forward for public sector PM research. Overall the paper makes a number of contributions. First, it brings together a disparate and fragmented field in reviewing studies examining the risks of PM. Second, the paper reframes the research question that public sector PM risk research and public sector PM studies more broadly should engage in. Third, specific suggestions are offered in terms of how future research might proceed in a coordinated manner, examining and informing practice where PM is part of an integrated and enabling control system for strategising and managing in the public sector, and where citizen‐centric PM is utilised as part of multiple evaluation modes to more effectively support accountability to external constituents.
What Lies Beneath? The Role of Informal and Hidden Networks in the Management of Crises
Authors: Fischbacher‐Smith Denis , Fischbacher‐Smith Moira 
Published: July 2014

AbstractCrisis management research traditionally focuses on the role of formal communication networks in the escalation and management of organisational crises. Here, we consider instead informal and unobservable networks. The paper explores how hidden informal exchanges can impact upon organisational decision‐making and performance, particularly around inter‐agency working, as knowledge distributedacrossorganisations and sharedbetweenorganisations is often shared through informal means and not captured effectively through the formal decision‐making processes. Early warnings and weak signals about potential risks and crises are therefore often missed. We consider the implications of these dynamics in terms of crisis avoidance and crisis management.
Epigenetic regulation of adult stem cell function
Authors: Rinaldi Lorenzo , Benitah Salvador Aznar 
Published: July 2014

Understanding the cellular and molecular mechanisms that specify cell lineages throughout development, and that maintain tissue homeostasis during adulthood, is paramount towards our understanding of why we age or develop pathologies such as cancer. Epigenetic mechanisms ensure that genetically identical cells acquire different fates during embryonic development and are therefore essential for the proper progression of development. How they do so is still a matter of intense investigation, but there is sufficient evidence indicating that they act in a concerted manner with inductive signals and tissue‐specific transcription factors to promote and stabilize fate changes along the three germ layers during development. In consequence, it is generally hypothesized that epigenetic mechanisms are also required for the continuous maintenance of cell fate during adulthood. However, in vivo models in which different epigenetic factors have been depleted in different tissues do not show overt changes in cell lineage, thus not strongly supporting this view. Instead, the function of some of these factors appears to be primarily associated with tissue functionality, and a strong causal relationship has been established between their misregulation and a diseased state. In this review, we summarize our current knowledge of the role of epigenetic factors in adult stem cell function and tissue homeostasis.
Egg fertilisation in a freshwater mussel: effects of distance, flow and male density
Authors: Mosley Tyler L. , Haag Wendell R. , Stoeckel James A. 
Published: July 2014

Summary

Small or sparse populations can experience Allee effects if egg fertilisation is reduced because of a shortage of sperm.

Freshwater mussels are spermcasters that often occur as sparse, patchy populations. Previous studies suggested that sperm shortage limits these populations unless facultative hermaphroditism and self‐fertilisation occur at low density. We conducted experiments in ponds to examine fertilisation in the mussel, Lampsilis straminea, in response to flow, presence of and distance from males, male density, and the presence of upstream females that could compete for sperm with downstream females.

Self‐fertilisation in the absence of males did not occur in either experiment. Female fertilisation success was uniformly high in most treatments and was not related to flow or distance from males (1–25 m). Fertilisation success was significantly lower at low male density (0.02 m−2, compared with 0.16 m−2) but remained relatively high even in most low male density treatments. The proportion of females that became gravid was higher in the presence of upstream females, but fecundity was significantly lower when upstream females were present; these conflicting results made it difficult to assess the role of competition among females for sperm.

Overall, high fertilisation success occurred at densities three orders of magnitude lower than previously proposed thresholds for mussels. Sperm dispersal and acquisition and egg fertilisation appear to be complex processes associated with adaptations for spermcasting. These adaptations are likely to facilitate persistence at low population density and buffer mussels from reproductive Allee effects.
Vulnerability of ecosystems to climate change moderated by habitat intactness
Authors: Eigenbrod Felix , Gonzalez Patrick , Dash Jadunandan , Steyl Ilse 
Published: July 2014

AbstractThe combined effects of climate change and habitat loss represent a major threat to species and ecosystems around the world. Here, we analyse the vulnerability of ecosystems to climate change based on current levels of habitat intactness and vulnerability to biome shifts, using multiple measures of habitat intactness at two spatial scales. We show that the global extent of refugia depends highly on the definition of habitat intactness and spatial scale of the analysis of intactness. Globally, 28% of terrestrial vegetated area can be considered refugia if all natural vegetated land cover is considered. This, however, drops to 17% if only areas that are at least 50% wilderness at a scale of 48 × 48 km are considered and to 10% if only areas that are at least 50% wilderness at a scale of 4.8 × 4.8 km are considered. Our results suggest that, in regions where relatively large, intact wilderness areas remain (e.g. Africa, Australia, boreal regions, South America), conservation of the remaining large‐scale refugia is the priority. In human‐dominated landscapes, (e.g. most of Europe, much of North America and Southeast Asia), focusing on finer scale refugia is a priority because large‐scale wilderness refugia simply no longer exist. Action to conserve such refugia is particularly urgent since only 1 to 2% of global terrestrial vegetated area is classified as refugia and at least 50% covered by the global protected area network.
A Hybridized GA with LP‐LP Model for the Management of Confined Groundwater
Authors: Khadem M. , Afshar M.H. 
Published: July 2014

AbstractA novel hybrid methodology is introduced in this paper for the optimal solution of the groundwater management problem. The problem to be addressed is the optimal determination and operation of a predefined number of wells out of a priori known set of potential wells with fixed locations to minimize the pumping cost of utilizing a two‐dimensional (2D) confined aquifer under steady‐state flow condition. The solution to this problem should satisfy a downstream demand, a lower/upper bound on the pumping rates, and a lower/upper bound on the water level drawdown in the wells. The problem is solved by hybridizing a genetic algorithm (GA) which suggests the candidate configurations for the operational wells and a hybrid linear programming (LP‐LP) approach with the duty of finding the optimal operation policy of the candidate wells defined by their pumping rates. Two different codings, namely binary and integer codings, are used for the GA and their performances are compared. The ability of the proposed hybrid method is tested against two benchmark problems: (1) finding the optimal configuration and pumping rates of a predefined number of wells out of potential wells and (2) finding the optimal number, configuration and pumping rates of the operating wells out of potential wells and the results are presented and compared with the available ones showing superior efficiency and effectiveness of the proposed method.
Nonlinear Flow Process: A New Package to Compute Nonlinear Flow in MODFLOW
Authors: Mayaud Cyril , Walker Patrica , Hergarten Stefan , Birk Steffen 
Published: July 2014

AbstractA new MODFLOW package (Nonlinear Flow Process; NLFP) simulating nonlinear flow following the Forchheimer equation was developed and implemented in MODLFOW‐2005. The method is based on an iterative modification of the conductance calculated and used by MODFLOW to obtain an effective Forchheimer conductance. The package is compatible with the different layer types, boundary conditions, and solvers as well as the wetting capability of MODFLOW. The correct implementation is demonstrated using four different benchmark scenarios for which analytical solutions are available. A scenario considering transient flow in a more realistic setting and a larger model domain with a higher number of cells demonstrates that NLFP performs well under more complex conditions, although it converges moderately slower than the standard MODFLOW depending on the nonlinearity of flow. Thus, this new tool opens a field of opportunities to groundwater flow simulation with MODFLOW, especially for core sample simulation or vuggy karstified aquifers as well as for nonlinear flow in the vicinity of pumping wells.
The perspectives of Aboriginal patients and their health care providers on improving the quality of hemodialysis services: A qualitative study
Authors: Rix Elizabeth F. , Barclay Lesley , Stirling Janelle , Tong Allison , Wilson Shawn 
Published: July 2014

AbstractChronic kidney disease has a higher prevalence in Indigenous populations globally. The incidence of end‐stage kidney disease in Australian Aboriginal people is eight times higher than non‐Aboriginal Australians. Providing services to rural and remote Aboriginal people with chronic disease is challenging because of access and cultural differences. This study aims to describe and analyze the perspectives of Aboriginal patients' and health care providers' experience of renal services, to inform service improvement for rural Aboriginal hemodialysis patients. We conducted a thematic analysis of interviews with Aboriginal patients (n = 18) receiving hemodialysis in rural Australia and health care providers involved in their care (n = 29). An overarching theme of avoiding the “costly” crisis encompassed four subthemes: (1) Engaging patients earlier (prevent late diagnosis, slow disease progression); (2) flexible family‐focused care (early engagement of family, flexibility to facilitate family and cultural obligations); (3) managing fear of mainstream services (originating in family dialysis experiences and previous racism when engaging with government organizations); (4) service provision shaped by culture (increased home dialysis, Aboriginal support and Aboriginal‐led cultural education). Patients and health care providers believe service redesign is required to meet the needs of Aboriginal hemodialysis patients. Participants identified early screening and improving the relationship of Aboriginal people with health systems would reduce crisis entry to hemodialysis. These strategies alongside improving the cultural competence of staff would reduce patients' fear of mainstream services, decrease the current emotional and family costs of care, and increase efficiency of health expenditure on a challenging and increasingly unsustainable treatment system.
Earlier financial literacy and later financial behaviour of college students
Authors: Xiao Jing Jian , Ahn Sun Young , Serido Joyce , Shim Soyeon 
Published: July 2014

AbstractThis study examined the association of earlier financial literacy and later financial behaviour of college students. Financial literacy was measured by both subjective and objective knowledge and financial behaviours were categorized into risky paying and borrowing behaviours. Based on data collected at two time points from a panel of college students at a major state university in the USA, the results showed that the association between earlier knowledge and later financial behaviours differed by the specific type of knowledge (subjective vs. objective), with stronger effect of subjective knowledge, compared with objective knowledge on both composite and individual measures of risky borrowing and paying behaviours. We found that only subjective knowledge was correlated with a reduction in both composite behaviours. Both subjective and objective knowledge, however, reduced some specific risky paying and borrowing behaviours. Finally, we found consistent differences for two of the control variables: higher GPA (Grade Point Average) was associated with fewer risky paying behaviours; and gender (male vs. female) was associated with more of both types of risky behaviours.