Principals between exploitation and exploration: Results of a nationwide study on ambidexterity of school leaders

Both organizational and management research suggest that schools and their leaders need to be ambidextrous to secure prosperity and long-term survival in dynamic environments characterized by competition and innovation. In this context, ambidexterity refers to the ability to simultaneously pursue exploitation and exploration and thus to deliver efficiency, control and incremental improvements while embracing flexibility, autonomy and discontinuous innovation. Using a unique, randomized and representative data set of N = 405 principals, we present findings on principals’ exploitation and exploration. The results indicate: (a) that principals engage far more often in exploitative than in explorative activities; (b) that exploitative activities in schools are executed at the expense of explorative activities; and (c) that explorative and ambidextrous activities of principals are positively associated with the (perceived) competition between schools. The study brings a novel perspective to educational research and demonstrates that applying the concept of ambidexterity has the potential to further our understanding of effective educational leadership and management.

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The duration of global agri-food export competitiveness

British Food Journal ◽

10.1108/bfj-07-2016-0302 ◽

2017 ◽

Vol 119 (6) ◽

pp. 1378-1393 ◽

Cited By ~ 11

Author(s):

Štefan Bojnec ◽

Imre Fertő

Keyword(s):

Comparative Advantage ◽

Agricultural Land ◽

Survival Rates ◽

Revealed Comparative Advantage ◽

Data Set ◽

Term Survival ◽

Content Type ◽

Country Level ◽

Export Competitiveness

Purpose The purpose of this paper is to examine the pattern, duration and country-level determinants of global agri-food export competitiveness of 23 major global agri-food trading countries. Design/methodology/approach A large panel data set is compiled to facilitate assessment of the pattern, duration and country-level determinants of global agri-food export competitiveness using a revealed comparative advantage index. Findings The results suggest that the duration of revealed comparative advantage is heterogeneous at the agri-food product level. Long-term survival rates as revealed by the comparative advantage indices are among the highest for the Netherlands, France, Belgium, the USA, Argentina and New Zealand. The level of economic development, the share of agricultural employment, subsidies to agriculture and differentiated consumer agri-food products increase the likelihood of failure in the duration of comparative advantage, while the abundance of agricultural land and export diversification reduce that likelihood. Originality/value The framework is conceptually innovative in how it models the likelihood of failure in the duration of comparative advantage and assesses implications. Export competitiveness is a crucial factor in long-term global farm business survival as it fosters opportunities for business prosperity on global markets.

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Renal recovery and long-term survival following acute kidney injury after coronary artery surgery: a nationwide study

Acta Anaesthesiologica Scandinavica ◽

10.1111/aas.12758 ◽

2016 ◽

Vol 60 (9) ◽

pp. 1230-1240 ◽

Cited By ~ 21

Author(s):

S. Helgadottir ◽

M. I. Sigurdsson ◽

R. Palsson ◽

D. Helgason ◽

G. H. Sigurdsson ◽

...

Keyword(s):

Acute Kidney Injury ◽

Coronary Artery ◽

Kidney Injury ◽

Renal Recovery ◽

Coronary Artery Surgery ◽

Term Survival ◽

Long Term Survival ◽

Nationwide Study

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Actual long-term survival in HCC patients with portal vein tumor thrombus after liver resection: a nationwide study

Hepatology International ◽

10.1007/s12072-020-10032-2 ◽

2020 ◽

Vol 14 (5) ◽

pp. 754-764 ◽

Cited By ~ 2

Author(s):

Zhen-Hua Chen ◽

Xiu-Ping Zhang ◽

Yu-Gang Lu ◽

Le-Qun Li ◽

Min-Shan Chen ◽

...

Keyword(s):

Liver Resection ◽

Portal Vein ◽

Tumor Thrombus ◽

Portal Vein Tumor Thrombus ◽

Term Survival ◽

Long Term Survival ◽

Nationwide Study

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Long-term outcomes among octogenarians with aneurysmal subarachnoid hemorrhage

Journal of Neurosurgery ◽

10.3171/2018.3.jns173057 ◽

2019 ◽

Vol 131 (2) ◽

pp. 426-434 ◽

Cited By ~ 4

Author(s):

Hormuzdiyar Dasenbrock ◽

William B. Gormley ◽

Yoojin Lee ◽

Vincent Mor ◽

Susan L. Mitchell ◽

...

Keyword(s):

Subarachnoid Hemorrhage ◽

Treatment Modality ◽

Aneurysmal Subarachnoid Hemorrhage ◽

Long Term Outcomes ◽

Data Set ◽

Term Survival ◽

Microsurgical Clipping ◽

Male Sex ◽

National Analysis

OBJECTIVEData evaluating the long-term outcomes, particularly with regard to treatment modality, of aneurysmal subarachnoid hemorrhage (SAH) in octogenarians are limited. The primary objectives were to evaluate the disposition (living at home vs institutional settings) and analyze the predictors of long-term survival and return to home for octogenarians after SAH.METHODSData pertaining to patients age 80 and older who underwent microsurgical clipping or endovascular coiling for SAH were extracted from 100% nationwide Medicare inpatient claims and linked with the Minimum Data Set (2008–2011). Patient disposition was tracked for 2 years after index SAH admission. Multivariable logistic regression stratified by aneurysm treatment modality, and adjusted for patient factors including SAH severity, evaluated predictors of return to home at 60 and 365 days after SAH. Survival 365 days after SAH was analyzed with a multivariable Cox proportional hazards model.RESULTSA total of 1298 cases were included in the analysis. One year following SAH, 56% of the patients had died or were in hospice care, 8% were in an institutional post–acute care setting, and 36% had returned home. Open microsurgical clipping (adjusted hazard ratio [aHR] 0.67, 95% confidence interval [CI] 0.54–0.81), male sex (aHR 0.70, 95% CI 0.57–0.87), tracheostomy (aHR 0.63, 95% CI 0.47–0.85), gastrostomy (aHR 0.60, 95% CI 0.48–0.76), and worse SAH severity (aHR 0.94, 95% CI 0.92–0.97) were associated with reduced likelihood of patients ever returning home. Older age (aHR 1.09, 95% CI 1.05–1.13), tracheostomy (aHR 2.06, 95% CI 1.46–2.91), gastrostomy (aHR 1.55, 95% CI 1.14–2.10), male sex (aHR 1.66, 95% CI 1.20–2.23), and worse SAH severity 1.51 (95% CI 1.04–2.18) were associated with reduced survival.CONCLUSIONSIn this national analysis, 56% of octogenarians with SAH died, and 36% returned home within 1 year of SAH. Coil embolization predicted returning to home, which may suggest a benefit to endovascular treatment in this patient population.

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Influence of Age on Choice of Therapy and Surgical Outcomes in Patients with Nonsmall Cell Lung Cancer

The American Surgeon ◽

10.1177/000313480907500711 ◽

2009 ◽

Vol 75 (7) ◽

pp. 598-604 ◽

Cited By ~ 1

Author(s):

William D. Bolton ◽

David C. Rice ◽

Arlene M. Correa ◽

Wayne Hofstetter ◽

Ritsuko Komaki ◽

...

Keyword(s):

Lung Cancer ◽

Surgical Outcomes ◽

Pulmonary Resection ◽

The Elderly ◽

Data Set ◽

Term Survival ◽

Cancer Management ◽

Institutional Data ◽

Surgical Data

United States census data predict expansion of the elderly population until 2050 and nonsmall lung cancer (NSCLC) incidence is expected to rise accordingly. This study examines trends of lung cancer management and outcomes for pulmonary resection of primary NSCLC in the elderly. An institutional data set (n = 5950) was examined to determine patterns of management. A separate surgical dataset (n = 1756) was examined to determine surgical outcomes. “Elderly” was defined as 70 years old or older. Twenty-four per cent of patients in the institutional data set underwent surgery. Patients in the youngest age quartile (younger than 62 years) were more likely to undergo surgery, whereas the oldest quartile (older than 74 years) were less likely. In the surgical data set, 643 patients were elderly. No difference in combined 30-day/in-hospital mortality was noted (4 vs 2.9%). Five-year survival was 59.1 per cent for younger and 49.9 per cent for elderly patients. On multivariable analysis, age 70 years or older, male gender, increasing Charlson Comorbidity Index score, and pathologic stage were predictors of worse survival. Increasing age is an independent rick factor for surgical outcome and long-term survival after pulmonary resection for NSCLC, age appears to influence choice of initial treatment and extent of resection. Although surgery in the elderly carries higher risk, long-term cure can still be achieved in a significant number of patients.

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Habitat structure and diversity influence the nesting success of an endangered large cavity-nesting bird, the Southern Ground-hornbill

Koedoe ◽

10.4102/koedoe.v59i1.1438 ◽

2017 ◽

Vol 59 (1) ◽

Cited By ~ 3

Author(s):

Leigh Combrink ◽

Hendrik J. Combrink ◽

André J. Botha ◽

Colleen T. Downs

Keyword(s):

Habitat Structure ◽

Bird Species ◽

Nesting Success ◽

Bush Encroachment ◽

Data Set ◽

Large Herbivores ◽

Term Survival ◽

Nest Sites ◽

Large Trees

Habitat features can have a profound effect on the nesting success of birds. Savannas are often managed with predators and large herbivores as priority species, with little thought to the many bird species that management decisions could affect. Using a data set spanning seven breeding seasons, we examined how nesting success of Southern Ground-hornbills (SGHs) Bucorvus leadbeateri in the Kruger National Park varied as a result of various environmental and habitat factors within a radius of 3 km surrounding the nest site. Identifying which factors affect nesting success will allow for targeted management efforts to ensure the long-term survival of SGHs both within and outside of protected areas. Habitat structure and diversity of the vegetation surrounding the nest were the most influential factors on SGH nesting success. SGHs require open grassy areas for foraging and areas with large trees for nesting. Savanna habitat drivers such as elephants and fire should be managed to ensure that sufficient large trees are able to establish in the landscape and to control for bush encroachment. This is especially important in areas earmarked for SGH reintroductions. Nest sites of SGHs should be monitored to mitigate any structural changes in the habitat surrounding the nests. Nests should be modified or artificial nest sites provided, where nests have been damaged or lost, to ensure the continued presence of these birds in African savannas.Conservation implications: Habitat structure and diversity surrounding Southern Groundhornbill nests has a significant impact on their nesting success. This highlights the importance of monitoring vegetation change in savanna habitats where they occur. Management of savanna areas should take factors that influence bush encroachment, such as fire and elephants, into account to ensure the long-term persistence of these birds.

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Clinical outcomes in 1731 patients undergoing mitral valve surgery for rheumatic valve disease

Heart ◽

10.1136/heartjnl-2017-312249 ◽

2017 ◽

Vol 104 (10) ◽

pp. 841-848 ◽

Cited By ~ 17

Author(s):

Wan Kee Kim ◽

Ho Jin Kim ◽

Joon Bum Kim ◽

Sung-Ho Jung ◽

Suk Jung Choo ◽

...

Keyword(s):

Mitral Valve ◽

Propensity Score ◽

Large Data ◽

Matched Cohort ◽

Valve Repair ◽

Data Set ◽

Term Survival ◽

Significant Difference ◽

The Impact

ObjectiveUnlike degenerative mitral valve (MV) disease, the advantages of valve repair procedure over replacement have been debated in rheumatic MV disease. This study aims to evaluate the impact of procedural types on long-term outcomes through analyses on a large data set from an endemic area of rheumatic disease.MethodsWe evaluated 1731 consecutive patients (52.3±12.5 years; 1190 women) undergoing MV surgery for rheumatic MV disease between 1997 and 2015. Long-term survival and valve-related outcomes were compared between repair and replacement procedures. To adjust for selection bias, propensity score analyses were performed.ResultsPatients undergoing repair were younger and had more predominant mitral regurgitation than mechanical and bioprosthetic replacement groups (61.6% vs 15.6% vs 24.4%; P<0.001). During follow-up (130.9±27.7 months), 283 patients (16.3%) died and 256 patients (14.8%) experienced valve-related complications. Propensity score matching yielded 188 pairs of repair and replacement patients that were well balanced for baseline covariates. In the matched cohort, there was no significant difference in the mortality risk between the repair and replacement groups (HR, 1.24; 95% CI 0.62 to 2.48). The risk of composite valve-related complications, however, was significantly lower in repair group (HR, 0.57; 95% CI 0.33 to 0.99) principally derived by a lower risk of haemorrhagic events (HR, 0.23; 95% CI 0.07 to 0.70). The incidence of reoperation was not significantly different between groups in the matched cohort (HR, 1.62; 95% CI 0.49 to 5.28).ConclusionValve repair in well-selected patients with severe rheumatic MV disease led to comparable survival, but superior valve-related outcomes compared with valve replacement surgery.

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