bluuebunny/crossref_metadata_2025 huggingface dataset:
Picking professionals: a client-centric knowledge assessment framework
Authors: Skjølsvik Tale , Breunig Karl Joachim
Published: November 2018

Purpose

This paper aims to explore how professional competences are defined and assessed by clients of professional service firms (PSFs). Extant research has studied the knowledge base of professionals, but limited research has been conducted to develop an understanding of how clients value this knowledge.

Design/methodology/approach

The study is based on in-depth qualitative research design, which is suitable for inductive theory building. The collected data consist of interviews with 80 clients and sellers of professional services.

Findings

The authors offer a framework detailing the interrelationships between knowledge, experience and references as assessed by clients. In particular, references are used to evaluate experience, which in turn function as a proxy for how clients assess knowledge. Also, the study shows how the clients’ assessment of professional knowledge assets involves multiple levels and factors.

Research limitations/implications

Limited research has been conducted to understand client preferences and PSF competitive advantage from a client perspective. This paper contributes to extant literature on knowledge management by integrating it with insights from recent developments within service marketing focusing on client centricity and the role of clients in value creation. This perspective complements and extends what is already known about knowledge management.

Practical implications

The paper suggests that while it is essential to manage knowledge as such, references and experience has a very central role in selling and commercializing knowledge-intensive services. Thus, to the degree that clients buy knowledge, sellers should think carefully about how experience and references are developed, captured and conveyed to clients. From a client point, the identified framework has value in offering a client-centric conceptualization of knowledge that can be used as a starting point in defining their knowledge needs and in structuring and professionalizing their purchasing efforts related to professional services.

Originality/value

Knowledge-intensive service organizations sell their knowledge and resources to clients directly as experts and indirectly through their services. It is therefore imperative for these organizations to understand how their knowledge is evaluated by buyers. The paper takes a unique client-centric perspective in understanding knowledge from a buyer’s point of view and as perceived by the buyer, which largely has been lacking in existing knowledge management research.
Corporate payout-form: investors’ preference and catering theory
Authors: Chazi Abdelaziz , Theodossiou Alexandra , Zantout Zaher
Published: November 2018

Purpose

The purpose of this paper is to develop and validate new robust measures of investors’ preference for the form of regular corporate payout. Then, the paper adds to the empirical evidence on catering theory by examining managers’ catering to such preference.

Design/methodology/approach

The authors use the matching method to control for firm characteristics. The authors apply two robustness tests to validate the measures. The authors use the rigorous multivariate analysis.

Findings

US investors’ preference for regular dividends vs regular stock repurchases, being different forms of corporate payout, varies over time. Managers cater to investors’ preference for payout form. The findings are consistent with the catering theory of Baker and Wurgler (2004a). The number of firms that pay cash dividends regularly continue to outnumber the ones that purchase their shares regularly.

Research limitations/implications

The study only uses US data. It does not cover other countries.

Practical implications

The measures can be used in several future research endeavors, such as examining investors’ payout-form preferences in other countries (see Booth and Zhou, 2017) and exploring their determinants, the corporate governance characteristics of firms that cater to investors’ preference vs firms that do not, etc.

Social implications

The study contributes to understanding investors’ preferences and corporate payout behavior which is prerequisite to efficient policy formulation.

Originality/value

The proxies for investors’ payout-form preference control for firm characteristics and are unrelated to investors’ time-varying risk preferences. Also, they are robust to measurement issues. Moreover, the study covers a period of 40 years.
International diversification during financial crises
Authors: Tai Chu-Sheng
Published: November 2018

Purpose

The purpose of this paper is to provide empirical evidence on how 1999–2001 dot-com crisis and 2007–2009 subprime crisis affect the gains from international diversification from the perspective of US investors.

Design/methodology/approach

A conditional international CAPM with asymmetric multivariate GARCH-M specification is used to estimate international diversification gains.

Findings

The authors find that over the entire sample period, the average gains from international diversification is statistically significant and about 1.253 percent per year. During the subprime crisis period, the average gains decreases to about 0.567 percent per year, but it increases to 2.829 percent per year during the dot-com crisis.

Research limitations/implications

These research findings although confirm the conjectures that international financial turmoil tends to increase the co-movements among global financial markets, are in contrast to the conjectures that international diversification does not work during the financial crisis as evidence from the dot-com crisis. Therefore, future research on international diversification should not just focus on the correlation among international financial markets and should adopt a fully parameterized asset pricing model to study this research topic.

Practical implications

Given the empirical results found in this paper that international diversification gains may be decreasing or increasing during the financial crisis, as long as investors are not able to predict international financial crises, it is the average gains from international diversification over the longer periods that should encourage investors to diversify, regardless of potentially lower benefits over the shorter periods of time.

Originality/value

The major value of this paper is that although the increase in the conditional correlation during the financial turmoil is consistent with previous studies, the empirical results clearly show that the impact of a financial crisis on the gains from international diversification cannot be solely determined by the correlation between domestic and world stock market returns since the gains also depend on the unsystematic risk from the domestic stock market. Consequently, it is premature for previous studies to conclude that the gain from international diversification is diminishing due to an increasing correlation among international stock markets during the financial crisis.
People make the brand: a commentary
Authors: Backhaus Kristin
Published: November 2018

Purpose

The paper aims at a commentary on Graham and Cascio, “The employer-branding journal: its relationship with cross-cultural branding, brand reputation and brand repair”.

Design/methodology/approach

Based on the authors’ statement that “people make the brand”, this paper discusses elements of brand making and brand breaking.

Findings

Specifically, the paper discusses the creation of the employer brand, the positives and negatives of employees as brand ambassadors and the manner in which word-of-mouth information influences brands.

Originality/value

This commentary reflects on Graham and Cascio’s work and concludes with suggestions for future research.
Effects of trainee characteristics, training attitudes and training need analysis on motivation to transfer training
Authors: Sahoo Malabika , Mishra Sumita
Published: November 2018

Purpose

Trainees’ motivation to transfer the training imparted is an important constituent in determining required training outcomes in organizations. The purpose of this study is to examine the effects of trainee characteristics, training attitudes and training need analysis on motivation to transfer training.

Design/methodology/approach

Research hypotheses were tested using a survey. A questionnaire was used to collect data from employees of an Indian governmental power transmission organization, attending any one soft skills training programme in the past year. Out of the 500 questionnaires distributed, 389 were deemed useable for the study, producing an effective response rate of 77.8 per cent.

Findings

The findings establish a direct and positive association between trainee characteristics, training attitudes and need analysis with transfer motivation.

Originality/value

This study contributes to extant literature by examining associations in hitherto underexplored areas such as that of training attitudes and training need analysis with transfer motivation. In addition, the findings provide insights into challenges pertaining to transfer motivation in soft skills training initiatives.
Stressor factors, internal communication and commitment to change among administrative staff in Malaysian public higher-education institutions
Authors: Zainun Nor Farah Hanis , Johari Johanim , Adnan Zurina
Published: November 2018

Purpose

The objective of this study is twofold. First, it examines the relationship between stressor factors (i.e. role overload, role conflict, role ambiguity, interpersonal conflict and organizational constraints) and commitment to change. Second, it investigates the moderating effect of internal communication in the hypothesized link.

Design/methodology/approach

A total of 225 administrative staff in the public higher education institutions located in the Northern Region of Peninsular Malaysia participated in the study. Structural equation modelling was used to test the hypotheses.

Findings

Role overload, role ambiguity and organizational constraints pose a substantial influence on commitment to change. Internal communication is a significant moderator in the association between role ambiguity and commitment to change.

Research limitations/implications

This study contributes to the Social Exchange Theory by assessing stressor factors as the predictors of commitment to change. Future studies can further extend the model by examining other variables related to stressor factors and extending the nomological networks of these factors in relation to commitment to organizational change.

Practical implications

This study makes explicit the need for management in public higher education institutions to consider stressor factors, particularly role overload, role ambiguity and organizational constraints, which affect the commitment to change. Furthermore, the aspect of internal communication in public higher education institutions deserves further attention by the management in alleviating role ambiguity and boosting commitment to change among the administrative staff.

Originality/value

The study is one of the pioneers to demonstrate that the presence of internal communication as a moderating factor in assessing the influence of stressors on commitment to change among administrative staff in public higher education institutions. Further, little empirical evidence on commitment to change in terms of normative, affective, and continuance in the setting of Malaysian public higher education institution is available in the literature.
The effect of ownership-control disparity on the Chinese firm’s real activity earnings management
Authors: Kim Sang Ho , An Yohan
Published: November 2018

Purpose

This paper aims to investigate the impact of the separation between control and cash flow rights (control-ownership disparity) on the earnings management practices of Chinese firms. The notable features of Chinese firms are those of concentrated ownership and the severe disparity that exists between the control and cash flow rights of controlling shareholders.

Design/methodology/approach

This study measures the level of Chinese firms’ earnings management by adopting two different methods of measurement: accrual-based earnings management (AEM) and real activity earnings management (REM). The authors also consider the possible trade-off effects between these two types of measurements. The data set in this study encompasses over 2,000 Chinese firms, using data from 2003 to 2015.

Findings

The results indicate that controlling shareholders are more likely to engage in AEM as their cash flow rights are more concentrated, while they are less likely to use REM as the disparity of control-cash flow rights increases. Further, this inverse relationship between REM and control-cash flow rights disparity becomes more pronounced in the case of a low cash flow rights group. As REM generally causes distortions in firms’ operations, it is possible that the controlling shareholders are more likely to constrain the use of REM as the disparity is perceived to grow. This result may indicate a reduced agency problem between controlling and minority shareholders due to the developing and/or existing ownership dispersions, which are mainly driven by recent reforms applied to Chinese capital markets. However, we do not entirely exclude the possibility of other types of expropriations by the controlling shareholders. It appears that the controlling shareholders are still able to exert a significant level of control, even following a substantial ownership dispersion, and they may seek alternative expropriation methods, including but not limited to intercorporate loan or related party transactions as the disparity of control-cash flow rights increases.

Originality/value

Although the Chinese economy is experiencing a series of reforms to infuse market forces into capital markets, little has been known about the effects of ownership-control disparity in Chinese firms. Our findings highlight the importance of the country specific context in this vein of research.
The benefit of intelligence officers
Authors: Bottema A. Johannes , Telep Cody W.
Published: November 2018

Purpose

The purpose of this paper is to explore the extent to which intelligence officers integrated at the patrol level contribute to successful case outcomes through information sharing.

Design/methodology/approach

This study utilizes multinomial logistic regression to analyze the outcomes of three years of Intelligence Officer Reports (IORs) submitted by officers trained in the Phoenix Police Department’s Intelligence Officer Program.

Findings

The majority of IORs are either tangible case successes or intelligence successes that have the capacity to become these, as opposed to non-successes. The type of success is impacted by a number of predictors. These include case categorization, nature of crime, information-gathering methods and perceived validity of information. Perceived reliability of information was the only non-significant predictor.

Research limitations/implications

The study suggests the benefits of looking at multiple predictors of success in understanding the value of information gathered by intelligence officers in the field. Limitations include a fair amount of missing data and potential lack of generalizability to other agencies. Future research will also consider alternative ways of measuring success and the nesting of reports within officers.

Practical implications

The study provides insight into key factors for optimizing tangible case outcomes when institutionalizing intelligence-led policing at the patrol level.

Originality/value

This is the first study to consider how intelligence-led policing at the patrol level may influence case outcomes, and, in turn, what factors may contribute to this. Findings provide some initial considerations for optimizing desirable case outcomes.
Toughness-based recovery efficiency of shape memory parts fabricated using material extrusion 3D printing technique
Authors: Garcia Rosales Carlos Alejandro , Kim Hoejin , Garcia Duarte Mario F. , Chavez Luis , Tseng Tzu-Liang Bill , Lin Yirong
Published: November 2018

Purpose

Shape memory polymers (SMPs) are classified as smart materials owing to their inherent stimulus-induced response. SMPs are capable of recovering partially or totally to its original shape after a high degree of deformation by external stimulus. The most used stimuli are thermal, light, magnetic field and electricity. This research aims to characterize the toughness property of thermo-responsive SMP specimens fabricated by the material extrusion (ME) process and to investigate the impact of ME parameters on specimen maximum load and load-displacement curves. Moreover, to investigate the recovery efficiency based on the initial and post toughness generated by the compact tension test.

Design/methodology/approach

A design of experiments with three parameters (temperature, velocity and layer height) defined the ME settings to fabricate the specimens. The ME raster orientation factor was also evaluated separately. In addition, one more specimen group assisted by a clamp during the recovery process was compared with a specimen control group. After fabrication, specimens were submitted to a thermo-mechanical cycle that encompasses a compact tension test and a thermo-recovery process. Comparison studies of load-displacement, toughness and recovery efficiency of the specimens were carried out to determine the optimized fabrication parameters.

Findings

It was found that ME parameters and raster orientation impacted the test results. Samples with the clamp support during recovery returned a higher toughness than samples without support. Finally, results showed that the shape memory effect can contribute with up to 43 per cent recovery efficiency in a first recovery and up to 23 per cent in a second recovery of damaged specimens.

Originality/value

This paper is a reference for toughness and recovery properties of SMP parts produced by the ME fabrication process.
Energy expenditure of patients on ECMO: A prospective pilot study
Authors: De Waele Elisabeth , Jonckheer Joop , Pen Joeri J. , Demol Joy , Staessens Kurt , Puis Luc , La Meir Mark , Honoré Patrick M. , L. N. G. Malbrain Manu , Spapen Herbert D.
Published: November 2018

Background

An optimal nutritional approach sustained by convenient monitoring of metabolic status and reliable assessment of energy expenditure (EE) may improve the outcome of critically ill patients on extracorporeal membrane oxygenation (ECMO). We previously demonstrated the feasibility of indirect calorimetry (IC)—the standard of care technique to determine caloric targets—in patients undergoing ECMO. This study aims to compare measured with calculated EE during ECMO treatment. We additionally provide median EE values for use in settings where IC is not available.

Methods

IC was performed in seven stable ECMO patients. Gas exchange was analyzed at the ventilator, and ECMO side and values were introduced in a modified Weir formula to calculate resting EE. Results were compared with EE calculated with the Harris‐Benedict equation and with the 25 kcal/kg/day ESPEN recommendation.

Results

Total median oxygen consumption rate was 196 (Q1‐Q3 158‐331) mL/min, and total median carbon dioxide production was 150 (Q1‐Q3 104‐203) mL/min. Clinically relevant differences between calculated and measured EE were observed in all patients. The median EE was 1334 (Q1‐Q3 1134‐2119) kcal/24 hours or 18 (Q1‐Q3 15‐27) kcal/kg/day.

Conclusion

Compared with measured EE, calculation of EE both over‐ and underestimated caloric needs during ECMO treatment. Despite a median EE of 21 kcal/kg/day, large variability in metabolic rate was found and demands further investigation.
The effect of isocapnic hyperventilation on early recovery after remifentanil/sevoflurane anesthesia in O2/air: A randomized trial
Authors: De Baerdemaeker Andy , Poelaert Jan , Kennedy R. Ross , De Wolf Andre M. , Hendrickx Jan F. A.
Published: November 2018

Background

Isocapnic hyperventilation (ICHV) may hasten emergence from general anesthesia but remains inadequately studied. We prospectively determined emergence time after sevoflurane anesthesia of variable duration with and without ICHV.

Methods

In 25 ASA I‐II patients, general anesthesia was maintained with one age‐adjusted MAC sevoflurane in O2/air and target‐controlled remifentanil delivery. At the start of skin closure, the remifentanil effect‐site concentration was reduced to 1.5 ng/mL, any residual neuromuscular block reversed, and once the remifentanil effect‐site concentration had decreased to 1.5 ng/mL, remifentanil and sevoflurane administration was stopped, and the fresh gas flow increased above minute ventilation. Patients randomly received either normoventilation (n = 13) or ICHV (doubling minute ventilation while titrating CO2 into the inspiratory limb to maintain isocapnia [n = 12]). Three early recovery end points were determined: time to proper response to verbal command; time to extubation; and time to stating one’s name.

Results

Demographics were the same in both groups. Recovery end points were reached faster in the ICHV group compared to the normoventilation group: time to proper response to verbal command was 7.6 ± 2.2 vs 9.9 ± 2.9 min (P = 0.03); time to extubation was 7.6 ± 2.6 vs 11.0 ± 2.4 min (P = 0.002); and time to stating one’s name was 8.9 ± 2.8 vs 12.5 ± 2.6 min (P = 0.003). Within each group, duration of anesthesia only marginally affected the times to reach these recovery end points.

Conclusion

Isocapnic hyperventilation only had a small effect on emergence times after anesthesia, suggesting that isocapnic hyperventilation may have limited clinical benefits with modern potent inhaled anesthetics.
An analysis of issues in the classification and reporting of heroin‐related deaths
Authors: Stam Nathan C. , Gerostamoulos Dimitri , Pilgrim Jennifer L. , Smith Karen , Moran Lauren , Parsons Sarah , Drummer Olaf H.
Published: November 2018

Aims

To investigate the extent of variability in the reporting of heroin‐related deaths in Victoria, Australia. Additionally, to identify opportunities to improve the accuracy and consistency of heroin‐related death reporting by examining variability in the attribution, death certification, classification and coding of heroin‐related death cases.

Methods

Heroin‐related deaths in Victoria, Australia during a 2‐year period (2012–13) were identified using the National Coronial Information System (NCIS) and used as the ‘gold standard’ measure in this study. Heroin‐related death data from the Australian Institute of Health and Welfare (AIHW) and Australian Bureau of Statistics (ABS) were then compared. Differences in the number of deaths reported as well as the classification and coding assigned to the identified heroin‐related death cases were investigated by cross‐referencing these data sets and examining the assigned ICD‐10 codes.

Results

A total of 243 heroin‐related deaths were identified through the NCIS compared with 165 heroin‐related deaths reported by the AIHW and assigned the heroin‐specific ICD‐10 code of T40.1. Forty per cent of all the missed heroin‐related death cases resulted from either the attribution of the death to morphine toxicity or with non‐specific drug toxicity certification; 30% occurred where the cases had been attributed to heroin but there were irregularities in death certification. Additional missed heroin‐related death cases occurred as a result of late initial registration of these deaths to the Registry of Births, Deaths and Marriages, and where these cases were then not assessed by the ABS for classification and coding purposes.

Conclusions

In Victoria, Australia, in 2012 and 2013, the overall number of heroin‐related deaths was under‐reported by 32% compared with the number of deaths currently identified by the Australian Bureau of Statistics and reported by the Australian Institute of Health and Welfare.
Early depletion of contact system in patients with sepsis: a prospective matched control observational study
Authors: Berkestedt Ingrid , Andersson Pia , Herwald Heiko , Valik John Karlsson , Sörensen Ola , Bodelsson Mikael
Published: November 2018

Activation of the contact system generates bradykinin from high‐molecular‐weight kininogen and has been suggested to participate in the pathophysiology of sepsis. To test this, we prospectively measured bradykinin and high‐molecular‐weight kininogen levels in a cohort of sepsis patients requiring intensive care. From 29 patients meeting criteria for sepsis or septic shock according to Sepsis‐3, blood was sampled within 24 h and on the fourth day following admittance to intensive care. Patients planned for neurosurgery served as matched controls. Sequential organ failure assessment score and 90‐day mortality was registered. Bradykinin levels (median [interquartile range]) were lower in sepsis patients (79 [62–172] pg/ml) compared to controls (130 [86–255] pg/ml, p < 0.025) and did not correlate with mortality or severity of circulatory derangement. High‐molecular‐weight kininogen levels were lower in sepsis patients (1.6 [0.8–4.8] densitometry units) compared to controls (4.4 [2.9–7.7] densitometry units, p < 0.001), suggesting previous contact system activation. High‐molecular‐weight kininogen levels were lower in non‐survivors than survivors (p = 0.003) and negatively correlated to severity of circulatory derangement. We conclude that a role for bradykinin in later stages of severe sepsis must be challenged. Low high‐molecular‐weight kininogen concentrations suggest that the decrease in bradykinin is due to substrate depletion.
Visual Exploration of Dynamic Multichannel EEG Coherence Networks
Authors: Ji C. , van de Gronde J. J. , Maurits N. M. , Roerdink J. B. T. M.
Published: November 2018

Electroencephalography (EEG) coherence networks represent functional brain connectivity, and are constructed by calculating the coherence between pairs of electrode signals as a function of frequency. Visualization of such networks can provide insight into unexpected patterns of cognitive processing and help neuroscientists to understand brain mechanisms. However, visualizing dynamic EEG coherence networks is a challenge for the analysis of brain connectivity, especially when the spatial structure of the network needs to be taken into account. In this paper, we present a design and implementation of a visualization framework for such dynamic networks. First, requirements for supporting typical tasks in the context of dynamic functional connectivity network analysis were collected from neuroscience researchers. In our design, we consider groups of network nodes and their corresponding spatial location for visualizing the evolution of the dynamic coherence network. We introduce an augmented timeline‐based representation to provide an overview of the evolution of functional units (FUs) and their spatial location over time. This representation can help the viewer to identify relations between functional connectivity and brain regions, as well as to identify persistent or transient functional connectivity patterns across the whole time window. In addition, we introduce the time‐annotated FU map representation to facilitate comparison of the behaviour of nodes between consecutive FU maps. A colour coding is designed that helps to distinguish distinct dynamic FUs. Our implementation also supports interactive exploration. The usefulness of our visualization design was evaluated by an informal user study. The feedback we received shows that our design supports exploratory analysis tasks well. The method can serve as a first step before a complete analysis of dynamic EEG coherence networks.
Physical performance and cognitive functioning among individuals with diabetes: Findings from the China Health and Retirement Longitudinal Study Baseline Survey
Authors: Zhang Meng , Liu Tingting , Li Changwei , Wang Jing , Wu Dongmei
Published: November 2018

Aims

The purpose of this study was to examine individual associations of each physical performance measure with domains of cognitive functioning and to determine best physical performance measures strongly associated with each domain of cognitive functioning among middle‐aged and older adults with diabetes.

Background

Tests of physical performance are strongly correlated with cognitive decline in general elderly population. However, far less is known about individual associations of each individual physical performance measure with domains of cognitive functioning among individuals with diabetes.

Design

The study employed a retrospective, cross‐sectional design.

Methods

Baseline data from a national baseline survey collected from May 2011–March 2012 were used. A total of 17,314 individuals aged ≥45 years completed the baseline survey. Diabetes was confirmed for 1,905 participants and these individuals were included in this study.

Results

When grip strength, walking speed, repeated chair stands and standing balance test were added in the regression models, walking speed was the only variable that was significantly associated with figure drawing and grip strength was the only variable that was significantly associated with episodic memory, orientation/attention and overall cognitive score.

Conclusion

Since grip strength was the most important factor associated with several domains of cognitive functioning, strategies that improve grip strength in patients with diabetes are prudent. Early interventions to increase levels of physical activity may be important to improve both grip strength and cognitive functioning in this growing population with diabetes.
Temporal trends in optimal diabetic care and complications of elderly type 2 diabetes patients in Thailand: A nationwide study
Authors: Kaewput Wisit , Thongprayoon Charat , Mungthin Mathirut , Jindarat Sarawut , Varothai Narittaya , Suwannahitatorn Picha , Rangsin Ram , Mao Michael A , Cheungpasitporn Wisit
Published: November 2018

Background

This study aimed to assess the nationwide trends in optimal diabetic care and complications of elderly type 2 diabetes mellitus (T2DM) patients over a 6‐year period in Thailand.

Methods

T2DM patients aged 65 years or older who received medical care at public hospitals in Thailand from 2010 to 2015 were included. The optimal T2DM care in elderly patients was defined as (1) blood pressure (BP) < 140/90, (2) hemoglobin A1C (HbA1c) < 7%, (3) low‐density lipoprotein cholesterol (LDL‐C) < 100 mg/dL, (4) use of antiplatelet medications, and (5) use of angiotensin‐converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) in hypertensive patients. T2DM treatment‐related complications included hospital admissions due to dysglycemia.

Results

A total of 54 295 elderly T2DM patients were enrolled in this study. From 2010 to 2015, there was an increasing trend in the achievement of BP control and use of antiplatelet medications (P for trend < 0.01), whereas there was a decreasing trend in the achievement of HbA1c and LDL‐C control among elderly T2DM patients (P for trend < 0.001). There was an increasing trend in the use of ACEI/ARB among elderly T2DM patients with hypertension (P for trend < 0.001). Hospital admissions due to dysglycemia decreased over the study period (P for trend < 0.001).

Conclusion

There has been a trend change for diabetic care among elderly T2DM patients in Thailand. Further studies are needed to assess the impact on patient outcomes.
P in the right place: Revisiting the evidential value of P‐values
Authors: Lytsy Per
Published: November 2018

P‐values are often calculated when testing hypotheses in quantitative settings, and low P‐values are typically used as evidential measures to support research findings in published medical research. This article reviews old and new arguments questioning the evidential value of P‐values. Critiques of the P‐value include that it is confounded, fickle, and overestimates the evidence against the null. P‐values may turn out falsely low in studies due to random or systematic errors. Even correctly low P‐values do not logically provide support to any hypothesis. Recent studies show low replication rates of significant findings, questioning the dependability of published low P‐values. P‐values are poor indicators in support of scientific propositions. P‐values must be inferred by a thorough understanding of the study's question, design, and conduct. Null hypothesis significance testing will likely remain an important method in quantitative analysis but may be complemented with other statistical techniques that more straightforwardly address the size and precision of an effect or the plausibility that a hypothesis is true.
Periprocedural antibiotic treatment in transvascular aortic valve replacement
Authors: Gomes Bruna , Geis Nicolas A. , Leuschner Florian , Meder Benjamin , Konstandin Mathias , Katus Hugo A. , Bekeredjian Raffi
Published: November 2018

Background

To date, there are no guidelines recommending a specific prophylactic antibiotic treatment in transcatheter aortic valve replacement (TAVR). The aim of this study is to evaluate clinical data after TAVR with different periprocedural antibiotic regimens.

Methods

In May 2015 the institutional rules for periprocedural antibiotic prophylaxis were changed from 3 days to 1 day. Thus, a total of 450 consecutive TAVR patients between February 2014 and June 2016 were classified into two intention‐to‐treat groups: patients receiving a 1‐day Cefuroxime prophylaxis (N = 225); patients receiving a 3‐day Cefuroxime prophylaxis (N = 225).

Results

One‐day Cefuroxime regimen was not associated with shorter hospitalization (3‐day Cefuroxime 9 ± 4.7 vs 1‐day Cefuroxime 8.9 ± 4.0; P = 0.87). Incidence of diarrhea (26.2% vs 18.2%; P = 0.04) and Clostridium difficile infections (4% vs 0.4%; P = 0.01) were significantly higher in the 3‐day group. No endocarditis was registered after 1 year follow‐up. There was no difference in 30‐day overall mortality rate, major vascular complications, bleeding complications, pacemaker‐implantation rate, paravalvular regurgitation, or acute kidney injury between patients groups.

Conclusion

Three‐day Cefuroxime prophylaxis does not seem to be advantageous compared to a shorter 1‐day regimen, but even shows a significantly higher incidence of diarrhea and Clostridium difficile infection.
White Matter Microstructure Correlates with Memory Performance in Healthy Children: A Diffusion Tensor Imaging Study
Authors: Samara Amjad , Feng Kaiyang , Pivik R. Terry , Jarratt Kelly P. , Badger Thomas M. , Ou Xiawei
Published: November 2018

BACKGROUND AND PURPOSE

The complex function of memory has been linked to both brain gray and white matter (WM). WM abnormalities are associated with memory impairment in pathological conditions. We investigated whether variation in WM microstructure in healthy children also correlates with memory performance.

METHODS

Sixty‐five 7.5 to 8.5‐year‐old healthy children had a brain MRI scan using diffusion tensor imaging (DTI). They were also assessed for memory performance using the Children's Memory Scale (CMS). Eight indices that evaluate verbal and visual memory (immediate and delayed) were measured. DTI parameters reflecting WM microstructure, including fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD), were calculated and correlated with memory indices.

RESULTS

Tract‐based spatial statistics analysis showed multiple WM tracts in which DTI parameters correlated with CMS indices. Specifically, FA (a reflection of WM integrity) and RD values (a reflection of myelination) in multiple projecting, association, and commissural WM tracts correlated with verbal delayed index (P < .05, corrected for voxel‐wise multiple comparisons). Also, FA values in several WM tracts, including superior longitudinal fasciculus and posterior corona radiata, positively correlated with delayed recognition index (P < .05, corrected). Region of interest analyses showed similar correlations between FA/RD and CMS scores in WM regions involving these tracts and additionally in the cingulum, and detected additional MD–CMS correlations in several regions.

CONCLUSIONS

Significant correlations between DTI parameter values and CMS indices in multiple WM tracts in healthy children indicate that neuroimaging can sensitively detect brain WM changes associated with variations of memory function, even for that in the normal range.
Constancy of generalized Hodge–Tate weights of a local system
Authors: Shimizu Koji
Published: November 2018

Sen attached to each$p$-adic Galois representation of a$p$-adic field a multiset of numbers called generalized Hodge–Tate weights. In this paper, we discuss a rigidity of these numbers in a geometric family. More precisely, we consider a$p$-adic local system on a rigid analytic variety over a$p$-adic field and show that the multiset of generalized Hodge–Tate weights of the local system is constant. The proof uses the$p$-adic Riemann–Hilbert correspondence by Liu and Zhu, a Sen–Fontaine decompletion theory in the relative setting, and the theory of formal connections. We also discuss basic properties of Hodge–Tate sheaves on a rigid analytic variety.
Systolic ratio, index of closed orbits and convexity for tight contact forms on the three-sphere
Authors: Abbondandolo Alberto , Bramham Barney , Hryniewicz Umberto L. , Salomão Pedro A. S.
Published: November 2018

We construct a dynamically convex contact form on the three-sphere whose systolic ratio is arbitrarily close to 2. This example is related to a conjecture of Viterbo, whose validity would imply that the systolic ratio of a convex contact form does not exceed 1. We also construct, for every integer $n\geqslant 2$, a tight contact form with systolic ratio arbitrarily close to $n$ and with suitable bounds on the mean rotation number of all the closed orbits of the induced Reeb flow.
Response of Pounding Dynamic Vibration Neutralizer Under Harmonic and Random Excitation
Authors: Masri Sami F. , Caffrey John P.
Published: November 2018

Exact steady-state solutions are obtained for the motion of an single-degree-of-freedom (SDOF) system that is provided with a highly nonlinear auxiliary mass damper (AMD), which resembles a conventional dynamic vibration neutralizer (DVN), whose relative motion with respect to the primary system is constrained to remain within a specified gap, thus operating as a “pounding DVN.” This configuration of a conventional DVN with motion-limiting stops could be quite useful when a primary structure with a linear DVN is subjected to transient loads (e.g., earthquakes) that may cause excessive relative motion between the auxiliary and primary systems. Under the assumption that the motion of the nonlinear system under harmonic excitation is undergoing steady-state motion with two impacts per period of the excitation, an exact, closed-form solution is obtained for the system motion. This solution is subsequently used to develop an approximate analytical solution for the stationary response of the pounding DVN when subjected to random excitation with white spectral density and Gaussian probability distribution. Comparison between the analytically estimated rms response of the primary system and its corresponding response obtained via numerical simulation shows that the analytical estimates are quite accurate when the coupling (tuning parameters) between the primary system and the damper are weak, but only moderately accurate when the linear components of the tuning parameters are optimized. It is also shown that under nonstationary, the pounding DVN provides slightly degraded performance compared to the linear one but simultaneously limits the damper-free motion to specified design constraints.
Observer-Based Finite-Time Nonfragile Control for Nonlinear Systems With Actuator Saturation
Authors: Sakthivel R. , Mohana Priya R. , Wang Chao , Dhanalakshmi P.
Published: November 2018

This paper considers a design problem of dissipative and observer-based finite-time nonfragile control for a class of uncertain discrete-time system with time-varying delay, nonlinearities, external disturbances, and actuator saturation. In particular, in this work, it is assumed that the nonlinearities satisfy Lipschitz condition for obtaining the required results. By choosing a suitable Lyapunov–Krasovskii functional, a new set of sufficient conditions is obtained in terms of linear matrix inequalities, which ensures the finite-time boundedness and dissipativeness of the resulting closed-loop system. Meanwhile, the solvability condition for the observer-based finite-time nonfragile control is also established, in which the control gain can be computed by solving a set of matrix inequalities. Finally, a numerical example based on the electric-hydraulic system is provided to illustrate the applicability of the developed control design technique.
Challenges and Status on Design and Computation for Emerging Additive Manufacturing Technologies
Authors: Leung Yuen-Shan , Kwok Tsz-Ho , Li Xiangjia , Yang Yang , Wang Charlie C. L. , Chen Yong
Published: November 2018

The revolution of additive manufacturing (AM) has led to many opportunities in fabricating complex and novel products. The increase of printable materials and the emergence of novel fabrication processes continuously expand the possibility of engineering systems in which product components are no longer limited to be single material, single scale, or single function. In fact, a paradigm shift is taking place in industry from geometry-centered usage to supporting functional demands. Consequently, engineers are expected to resolve a wide range of complex and difficult problems related to functional design. Although a higher degree of design freedom beyond geometry has been enabled by AM, there are only very few computational design approaches in this new AM-enabled domain to design objects with tailored properties and functions. The objectives of this review paper are to provide an overview of recent additive manufacturing developments and current computer-aided design methodologies that can be applied to multimaterial, multiscale, multiform, and multifunctional AM technologies. The difficulties encountered in the computational design approaches are summarized and the future development needs are emphasized. In the paper, some present applications and future trends related to additive manufacturing technologies are also discussed.
Molecular Dynamics Simulation of Mechanical Polishing on Stainless Steel Using Diamond Nanoparticles
Authors: Ranjan Prabhat , Balasubramaniam R. , Jain V.K.
Published: November 2018

Mechanical polishing is one of the essential attributes of nanofinishing. To maintain precision during nanofinishing process, the mechanical polishing needs to be studied and analyzed at nanometric scale. In view of this, a set of molecular dynamics simulation has been carried out to analyze the process behavior and its effects on abrasive particles. After simulation, it is observed that the finishing force and velocity damage the abrasive particle by changing its phase from diamond cubic to graphite. Thus, the abrasive particles need replacement in a scheduled time-bound manner. In addition, a strategy has been proposed for efficient and economic polishing.
High-Dimensional Reliability-Based Design Optimization Involving Highly Nonlinear Constraints and Computationally Expensive Simulations
Authors: Li Meng , Sadoughi Mohammadkazem , Hu Chao , Hu Zhen , Eshghi Amin Toghi , Lee Soobum
Published: November 2018

Reliability-based design optimization (RBDO) aims at optimizing the design of an engineered system to minimize the design cost while satisfying reliability requirements. However, it is challenging to perform RBDO under high-dimensional uncertainty due to the often prohibitive computational burden. In this paper, we address this challenge by leveraging a recently developed method for reliability analysis under high-dimensional uncertainty. The method is termed high-dimensional reliability analysis (HDRA). The HDRA method optimally combines the strengths of univariate dimension reduction (UDR) and kriging-based reliability analysis to achieve satisfactory accuracy with an affordable computational cost for HDRA problems. In this paper, we improve the computational efficiency of high-dimensional RBDO by pursuing two new strategies: (i) a two-stage surrogate modeling strategy is adopted to first locate a highly probable region of the optimum design and then locally refine the accuracy of the surrogates in this region; and (ii) newly selected samples are updated for all the constraints during the sequential sampling process in HDRA. The results of two mathematical examples and one real-world engineering example suggest that the proposed HDRA-based RBDO (RBDO-HDRA) method is capable of solving high-dimensional RBDO problems with higher accuracy and comparable efficiency than the UDR-based RBDO (RBDO-UDR) and ordinary kriging-based RBDO (RBDO-kriging) methods.
Modeling Pipeline Metal Loss Defects at Tool Speed
Authors: Romney Matthew , Belanger Adrian
Published: November 2018

Accurate defect sizing is crucial for maintaining effective pipeline safety and operation. Under growing pressure from local, national and world organizations, pipeline operators demand improved magnetic flux leakage (MFL) metal-loss sizing accuracy and classification from in-line inspection (ILI) tools.

The axial MFL field response in pipeline steel near a metal-loss defect is a very complex phenomenon. Although critical for proper sizing model development, the effects of tool speed due to product flow is very difficult to model during finite element analysis (FEA) and therefore is often overlooked. However, understanding the dynamic MFL response is crucial for proper ILI tool design and the development of accurate defect sizing algorithms.

T.D. Williamson (TDW) utilizes dynamic computer simulation modeling, paired with laboratory testing, to develop the complex parametric relationships between metal loss geometry, pipeline material and ILI tool speed. The blend of simulation and physical test results allow for TDW to iterate more quickly across multiple physics variables with simulation models, while maintaining a firm footing in reality with physical test validation. Accurately simulating magnetic field responses of metal loss under dynamic conditions produces the data necessary to identify optimal magnetizer design, including optimizing sensor spacing and placement for metal-loss defect sizing and characterization.

This paper will provide an overview of advances in the use of computer simulation modeling for predicting dynamic flux leakage field response. Besides increasing accuracy, results from this work will extend specifications beyond optimal speed ranges and provide the basis for general corrosion profilometry predictions from decomposition of the full MFL signal.