bluuebunny/crossref_metadata_2025_split huggingface dataset:
Importance of modelling heteroscedasticity of survey index data in fishery stock assessments
Authors: Hyun Saang-Yoon , Maunder Mark N. , Rothschild Brian J. 
Published: April 2014

AbstractMany fish stock assessments use a survey index and assume a stochastic error in the index on which a likelihood function of associated parameters is built and optimized for the parameter estimation. The purpose of this paper is to evaluate the assumption that the standard deviation for the difference in the log-transformed index is approximately equal to the coefficient of variation of the index, and also to examine the homo- and heteroscedasticity of the errors. The traditional practice is to assume a common variance of the index errors over time for estimation convenience. However, if additional information is available about year-to-year variability in the errors, such as year-to-year coefficient of variation, then we suggest that the heteroscedasticity assumption should be considered. We examined five methods with the assumption of a multiplicative error in the survey index and two methods with that of an additive error in the index: M1, homoscedasticity in the multiplicative error model; M2, heteroscedasticity in the multiplicative error model; M3, M2 with approximate weighting and an additional parameter for scaling variance; M4–M5, pragmatic practices; M6, homoscedasticity in the additive error model; M7, heteroscedasticity in the additive error model. M1–M2 and M6–M7 are strictly based on statistical theories, whereas M3–M5 are not. Heteroscedasticity methods M2, M3, and M7 consistently outperformed the other methods. However, we select M2 as the best method. M3 requires one more parameter than M2. M7 has problems arising from the use of the raw scale as opposed to the logarithm transformation. Furthermore, the fitted survey index in M7 can be negative although its domain is positive.
The Impact of Cancer on the Clinical Outcome of Patients After Inferior Vena Cava Filter Placement
Authors: Narayan Anand , Hong Kelvin , Streiff Michael , Shinohara Russell , Frangakis Constantine , Coresh Josef , Kim Hyun S. 
Published: April 2014

Objectives:
Inferior vena cava (IVC) filters are placed to prevent pulmonary embolism, however, some studies have suggested that IVC filters are associated with exacerbated risks of deep vein/IVC thrombosis in cancer patients. The purpose of this study is to determine if cancer patients develop higher than expected rates of venous thromboembolism complications after filter placement compared with noncancer patients.

Materials and Methods:
A retrospective cohort study of consecutive patients who received filters (2002 to 2006) at Johns Hopkins was conducted. Exposures and outcomes were obtained by chart review. Relative risks (RR, 95% confidence interval [CI]) for outcomes in cancer versus noncancer patients were estimated using multistate models.

Results:
The cohort included 702 patients—246 with cancer and 456 without cancer. Cancer patients were older, more likely to be white and have filters placed for contraindications to anticoagulation (P<0.01). The most common cancers were lung (11.8%) and colorectal (10.6%). Cancer patients had an increase in venous thromboembolism (RR 1.9 [95% CI, 1.1, 3.2]) due to more deep venous thrombosis/IVC thrombosis (RR 1.7 [95% CI, 1.0, 3.0]). Higher pulmonary embolism rates in cancer were not statistically significant (RR 2.2 [95% CI, 0.8, 5.8]).

Conclusions:
Cancer patients have elevated risks of thrombotic complications compared with noncancer patients; however, these risks are not higher than expected based on historical controls.
Radiotherapy and Male Breast Cancer
Authors: Madden Nicholas A. , Macdonald Orlan K. , Call Jason A. , Schomas David A. , Lee Christopher M. , Patel Shilpen 
Published: April 2014

Background:The local-regional management of female breast cancer has been extensively investigated worldwide. The optimal approach for males diagnosed with breast cancer is less clear. We have analyzed the treatment of male breast cancer using a population-based national registry to determine the impact of surgery and radiation therapy on survival.Materials and Methods:The Surveillance Epidemiology and End Results (SEER) database was queried to identify males with invasive ductal carcinoma of the breast who underwent primary surgical resection (radical mastectomy, modified radical mastectomy, total mastectomy, or segmental) for the years 1983 to 2002. Demographic, clinical, and pathologic data were culled and analyzed to determine the impact of radiation therapy (RT) following resection. Survival rates were estimated using the Kaplan-Meier method and significance was determined using the log-rank test (P<0.05). Multivariate analysis with the Cox proportional hazards model was performed to determine factors significant for overall (OS) and cause-specific survival (CSS).Results:A total of 1337 patients met the eligibility criteria and were analyzed. Median follow-up was 7.3 years (range, 1 mo to 25 y). Most men underwent modified radical mastectomy (n=1062) with a minority undergoing segmental (n=113). About 329 men received postoperative external beam RT. The median rates of OS and CSS for all men were 10.5 years and not yet reached, respectively. The surgical procedure did not significantly associate with OS or CSS. By stage, RT was associated with improved OS for stage I (P=0.03). There was a trend for improved survival with stage II (P=0.21) and III (P=0.15). RT was not associated with improved CSS by stage. RT improved rates of OS and CSS in N2 patients without reaching statistical significance (P=0.10 and 0.22). On multivariate analysis, advancing age, stage and grade, and no postoperative RT predicted for worse OS. However, when controlled for those with known hormone receptor status (n=978), only the factors of advancing age, stage, grade, and hormone receptor negativity predicted for worse OS. Advancing age, stage, and grade were the only predictors of CSS irrespective of the cohort analyzed.Conclusions:The primary surgical procedure did not ultimately influence OS or CSS in this population-based registry of males with breast cancer. A statistically nonsignificant improvement with postoperative RT was observed in men with lymph node involvement, larger tumor size, or higher stage. When controlled for age, stage, and grade in multivariate analysis, postoperative RT predicted for improved OS but not CSS. These data suggest a beneficial effect of RT in the postoperative setting. A prospective study is necessary to further elucidate appropriate treatment strategies for men with breast cancer.
Expression of Sucrose Transporter cDNAs Specifically in Companion Cells Enhances Phloem Loading and Long-Distance Transport of Sucrose but Leads to an Inhibition of Growth and the Perception of a Phosphate Limitation
Authors: Dasgupta Kasturi , Khadilkar Aswad S. , Sulpice Ronan , Pant Bikram , Scheible Wolf-Rüdiger , Fisahn Joachim , Stitt Mark , Ayre Brian G. 
Published: April 2014

Abstract
Sucrose (Suc) is the predominant form of carbon transported through the phloem from source to sink organs and is also a prominent sugar for short-distance transport. In all streptophytes analyzed, Suc transporter genes (SUTs or SUCs) form small families, with different subgroups evolving distinct functions. To gain insight into their capacity for moving Suc in planta, representative members of each clade were first expressed specifically in companion cells of Arabidopsis (Arabidopsis thaliana) and tested for their ability to rescue the phloem-loading defect caused by the Suc transporter mutation, Atsuc2-4. Sequence similarity was a poor indicator of ability: Several genes with high homology to AtSUC2, some of which have phloem-loading functions in other eudicot species, did not rescue the Atsuc2-4 mutation, whereas a more distantly related gene, ZmSUT1 from the monocot Zea mays, did restore phloem loading. Transporter complementary DNAs were also expressed in the companion cells of wild-type Arabidopsis, with the aim of increasing productivity by enhancing Suc transport to growing sink organs and reducing Suc-mediated feedback inhibition on photosynthesis. Although enhanced Suc loading and long-distance transport was achieved, growth was diminished. This growth inhibition was accompanied by increased expression of phosphate (P) starvation-induced genes and was reversed by providing a higher supply of external P. These experiments suggest that efforts to increase productivity by enhancing sugar transport may disrupt the carbon-to-P homeostasis. A model for how the plant perceives and responds to changes in the carbon-to-P balance is presented.
Maternal education and child nutritional status: evidence from Uganda
Authors: Bbaale Edward 
Published: April 2014

Purpose
– The debate concerning the relationship between maternal education and child nutritional status is not a foregone conclusion. This paper aims to contribute to the existing debate by examining this relationship for the case of Uganda.

Design/methodology/approach
– Theoretically, the study was based on household models of optimization, just like in the standard consumer theory, to gain insights into household demand for the health good. Empirically, the paper employed maximum-likelihood probit models and computed marginal effects in order to obtain logically interpretable results.

Findings
– The paper finds that once the socio-economic factors are controlled for, the significance of maternal education, especially primary and secondary levels, in influencing child nutrition status decays but post-secondary education persists. Therefore, if mothers are exposed to the same socio-economic conditions, it is education of the mother beyond secondary level that generates a difference in the child nutrition outcomes.

Practical implications
– These findings suggest that efforts to improve the child health outcomes in the future need to target measures that aim to educate women beyond secondary level. The government program to extend free education at the secondary level is a good start and should be strengthened.

Originality/value
– Literature presents no consensus on the effect of maternal education and child nutritional status. It is often argued that maternal education is simply a proxy for the socio-economic conditions and geographical area of residence such its significance decays once these are controlled for. Yet others argue that maternal education is a single most important factor influencing child nutritional outcomes. The debate is still very hot and this study sought to contribute to this debate for the case of Uganda.
Bank competition, financial innovations and economic growth in Ghana
Authors: Adu-Asare Idun Anthony , Q.Q. Aboagye Anthony 
Published: April 2014

Purpose– This paper takes the finance-growth nexus further by looking at the relationship between bank competition, financial innovations and economic growth in Ghana. The purpose of this paper is to find the causality among bank competition, financial innovations and economic growth in Ghana.Design/methodology/approach– The relationship between bank competition, financial innovations and economic growth was established through the framework of the endogenous growth model. In addition, the paper employed the bound testing ARDL cointegration procedures to enable us to establish both short-run and long-run relationship between bank competition, financial innovations and economic growth. Granger causality test were also estimated to determine the direction of causality.Findings– The results showed that, in the long run, bank competition is positively related to economic growth while financial innovation is negatively related to economic growth. In the short run, bank competition is negatively related to economic growth. By the same token, financial innovation is positively related to economic growth in the short run. In terms of causality, the results showed that there is unidirectional Granger causality from bank competition to economic growth. However, there is bidirectional Granger causality between financial innovation and economic growth.Practical implications– The study therefore, recommends for more regulations toward a more competitive banking system with more innovative products tailored toward mobilization of savings and investment to growth induced sectors of the economy.Originality/value– This paper provides a time series perspective to the finance-growth nexus and highlights the potential contribution of effective banking development to the economic welfare of the Ghanaian citizens.
Reflecting upon child protection – the professional doctorate journey
Authors: Kettle Martin 
Published: April 2014

Purpose
– This paper draws on a recently completed professional doctorate thesis. The purpose of this paper is to explore how the research process mirrors the area being researched, and underscores the importance of the ability to tolerate ambiguity, in both the research process and in working to protect children.

Design/methodology/approach
– The doctorate used a constructivist grounded theory approach, and drew on 22 in-depth interviews with social workers and a sample of 20 serious case reviews. Central to the research process were issues of reflexivity and positionality, which were both crucial to the area under exploration.

Findings
– Central to the thesis on which this paper draws, and the professional doctorate is the notion of balance. Social workers and researchers have to negotiate both getting close to and achieving distance from, the subject of enquiry. Seeking and maintaining balance requires managing a number of dimensions, and the negotiation of ambiguity.

Originality/value
– This paper explores the complexity of “working the hyphen” of insider-outsider research, and argues that, as in child protection practice, insider-outsider research requires the adoption of strategies to both get close to, and achieve distance from, the subject of enquiry.
A systematic approach to the assessment of impact in a professional doctorate
Authors: Kumar Swapna 
Published: April 2014

Purpose
– The purpose of this paper is to present one approach to the measurement of impact in a professional doctorate in education that encompasses discipline-based coursework and practice-embedded research.

Design/methodology/approach
– Quantitative and qualitative data on the impact of the doctoral program were collected at regular intervals, with a focus on students’ application of program content in their professional practice and on students’ professional growth.

Findings
– The research design and the findings are discussed in the context of the larger debate surrounding the measurement of doctoral impact and the value of online doctoral degrees for practitioners.

Originality/value
– This paper presents the systematic collection of data over four years in a newly developed professional doctorate in education.
Developing researching professionals in an EdD program
Authors: R. Buss Ray , Zambo Ron , Zambo Debby , R. Williams Tiffany 
Published: April 2014

Purpose
– The purpose of this paper is to examine how entering students and graduating students from an education doctorate (EdD) program viewed themselves as learners, leaders, and action researchers. Further, the paper examines differences in the identity trajectories between the two groups. Finally, the paper suggested a new identity status – scholarly and influential practitioners (SaIP) emerged from melding the three identity statuses.

Design/methodology/approach
– The paper employed a mixed method design.

Findings
– Results indicated students new to the program held strong identities as learners and leaders, but not as action researchers; whereas graduates held stronger views of each type of identity, especially as researchers. Program features such as cycles of action research (CAR), and leader-scholar communities were instrumental in influencing graduates’ identities as researching professionals.

Research limitations/implications
– SaIP emerge when doctoral programs enhance the learner and leader identity statuses of doctoral students while at the same time fostering the construction of a researching professional identity status.

Practical implications
– Development of researching professionals can be accomplished by fostering a researcher ethos during their participation in a doctoral program. For working professionals, this can be accomplished by requiring and supporting ongoing CAR in a doctoral program.

Social implications
– With respect to social implications, researching professionals, especially those in education offer substantial promise of achieving the educational reforms the school so desperately need.

Originality/value
– This research examines how one institution has attempted to develop researching professionals during their preparation in an EdD program, which is based on Carnegie Project for the Education Doctorate (CPED) working principles and design features.
Improving managerial performance: a study on entrepreneurial and leadership competencies
Authors: Jena Sambedna , Kumar Sahoo Chandan 
Published: April 2014

Purpose
– The purpose of the study is to ascertain predictors for superior managerial performance with special emphasis on leadership and entrepreneurial competencies required in manufacturing units.

Design/methodology/approach
– The entrepreneurial and leadership competencies have been obtained from the existing literature to predict their impact on managerial performance. Primary data collected from the respondents (executives) of two manufacturing units by administering structured questionnaire. In total, 410 responses were obtained and analysed using the SPSS statistical software.

Findings
– A total of 15 independent variables were used in the study, only three factors extracted namely business knowledge, spirit of competitiveness and dimensions of leadership were found to be significant predictors of superior managerial performance. The proposed hypotheses for this study are found significant.

Practical implications
– The study identifies potential dimensions of entrepreneurial and leadership competencies that improve managerial performance. The research concentrates on identifying the most important aspects of these two competencies which are vital for superior managerial performance.

Originality/value
– This paper has clearly identified the specific entrepreneurial and leadership competencies that the executives can acquire to improve their performance within the organization.
Probing organizational efficiency
Authors: Kemal Avkiran Necmi 
Published: April 2014

Purpose– In investigating the performance of multidivisional organizations, ability to account for each division's importance and contribution enhances the deftness of resource allocation and targeting desired outcomes. With this motivation, the author aims to introduce network data envelopment analysis (NDEA) from operations research in this conceptual article and discuss how two articles from this journal can be extended using this approach.Design/methodology/approach– NDEA was first developed to deliver a more in-depth understanding of underlying sources of operational inefficiency. Thus, NDEA can be viewed as a peer benchmarking method useful in comparing performance of organizations and identifying divisional inefficiencies that may detract from overall performance. NDEA's ability to capture interactions among multiple variables in an objective manner based on actual observed data rather than sample averages is one of its key advantages.Findings– The author discusses how NDEA can be applied in organisational analysis by examining two articles from this journal. Briefly commenting on one of the cases here, the author shows that a network can be defined as the interacting divisions of cultural norms and structural forms. The potential improvements (i.e. horizontal re-alignment) indicated by NDEA can guide management on the extent organisational alignment that could be changed in reaching strategic aims. The author's theoretical model is conducive to assessing the amount and direction of change from the proposed alignment model in a multi-criteria framework – characteristics embraced by NDEA.Practical implications– Given the hierarchical nature of organizations where employees are nested in work groups or teams, groups nested in departments or divisions, and divisions nested in organizations, application of NDEA at various levels of analysis is feasible.Originality/value– NDEA's ability to account for each division's importance or assign desired weights inwhat-if analysesadds to flexibility in managerial decision-making regarding allocation of resources, or re-alignment of processes and targeting of desired outcomes. Such a method that does not assume independence among multiple performance measures provides additional assurance to those concerned about shortcomings of additive scales in complex organizations.
Supply chain management, supply performance and total quality management
Authors: Vanichchinchai Assadej 
Published: April 2014

Purpose
– This study aims to assess the level of supply chain management practices (SCMP), total quality management practices (TQMP) and firm's supply performance (FSP) in the automotive industry in Thailand and investigate the differences across organizational characteristics on SCMP, TQMP and FSP.

Design/methodology/approach
– Based on an extensive literature review, the measurement instruments for SCMP, TQMP and FSP were developed and validated by experts, pilot test and various statistical techniques. Descriptive statistics were employed to examine the existences of SCMP, TQMP and FSP in the sample companies. MANOVA was applied to test the differences across company ownership, company size, tier in the supply chain and ISO/TS 16949 on SCMP, TQMP and FSP.

Findings
– The author found that the measurements of SCMP, TQMP and FSP are reliable and valid. The automotive companies in Thailand apply TQMP much more extensively than SCMP. Their SCMP still emphasize efficient flows of information and materials at operational level to minimize transaction cost. Overall, Japanese companies, large companies, first-tier suppliers and the companies with ISO/TS 16949 have more intensively applied SCMP and TQMP and achieved a higher level of FSP.

Research limitations/implications
– The distribution of paper-based questionnaires was a convenience sample. Although data from a sample of 211 companies were collected, only 19 percent of them provided more than one response. Future research should apply different random sampling methods and investigate the reasons for and ways to improve the low multiple-response rate.

Practical implications
– The findings are beneficial to the managers who want to improve SCMP, TQMP and FSP through organization management.

Originality/value
– This study is one of the first to assess the existence of SCMP and FSP and to study the differences across organizational characteristics on SCMP and FSP in the automotive industry in developing countries. The existence and differences across organizational characteristics on TQMP were also confirmed.