Science mapping research on educational leadership and management in Turkey : a bibliometric review of international publications

Abstract: Over the past two decades, there have been significant efforts to investigate knowledge produc-tion in the field of educational leadership and management (EDLM) in non-Western contexts. Consistent with this effort, the present paper aims to identify the contribution of Turkish scholars to the international EDLM literature. More specifically, the review examined the volume, jour-nals, authors, types of papers, most frequently used keywords, citation impact, and co-citation networks of papers associated with Turkish EDLM scholars. Bibliometric methods were em-ployed to examine 313 papers published by Turkish scholars in internationally recognized jour-nals. The results show that while Turkish EDLM scholars have predominantly published in Tur-key-based journals, there has also been a substantial increase in the number of papers published in international journals in recent years. This literature is largely empirical with topical foci con-centrated on issues surrounding school leadership and organizational behavior. Author co-citation analysis identified three main Schools of Thought in the Turkish literature: Leadership for Learning, Leading Teachers, Administrative Behavior and Effects in Turkey. Several rec-ommendations are made in order to further develop EDLM field in both Turkey and other emerging countries

Polymorphisms of the acid sensing histidine kinase gene arsS in Helicobacter pylori populations from anatomically distinct gastric sites

Phase variation is frequently utilized by bacterial species to affect gene expression such that phenotypic variants are maintained within populations, ensuring survival as environmental or host conditions change. Unusual among Helicobacter pylori phase variable or contingency genes is arsS, encoding a sensory histidine kinase involved in the acid acclimation of the organism. The presence of a 3\u27 homopolymeric cytosine tract of variable length in arsS among Helicobacter pylori strains allows for the expression of various functional ArsS isoforms, differing in carboxy-terminal protein domains. In this study, we analyzed this 3\u27 arsS region via amplified fragment length polymorphism (AFLP) and sequencing analyses for H. pylori populations from 3 different gastric sites of 12 patients. Our data indicate the presence of multiple arsS alleles within each population of H. pylori derived from the gastric antrum, cardia, or corpus of these patients. We also show that H. pylori, derived from the same anatomical site and patient, are predicted to express multiple ArsS isoforms in each population investigated. Furthermore, we identify a polymorphic deletion within arsS that generates another alternate ArsS C-terminal end. These findings suggest that four C-terminal variations of ArsS adds to the complexity of the ArsRS acid adaptation mechanism as a whole and may influence the ability of H. pylori to persist in the gastric niche for decades. (c) 2012 Elsevier Ltd. All rights reserved

Crosstalk between the HpArsRS two-component system and HpNikR is necessary for maximal activation of urease transcription

Helicobacter pylori NikR (HpNikR) is a nickel dependent transcription factor that directly regulates a number of genes in this important gastric pathogen. One key gene that is regulated by HpNikR is ureA, which encodes for the urease enzyme. In vitro DNA binding studies of HpNikR with the ureA promoter (P-ureA) previously identified a recognition site that is required for high affinity protein/DNA binding. As a means to determine the in vivo significance of this recognition site and to identify the key DNA sequence determinants required for ureA transcription, herein, we have translated these in vitro results to analysis directly within H. pylori. Using a series of GFP reporter constructs in which the P-ureA DNA target was altered, in combination with mutant H. pylori strains deficient in key regulatory proteins, we confirmed the importance of the previously identified HpNikR recognition sequence for HpNikR-dependent ureA transcription. Moreover, we identified a second factor, the HpArsRS two-component system that was required for maximum transcription of ureA. While HpArsRS is known to regulate ureA in response to acid shock, it was previously thought to function independently of HpNikR and to have no role at neutral pH. However, our qPCR analysis of ureA expression in wildtype, Delta nikR and Delta arsS single mutants as well as a Delta arsS/nikR double mutant strain background showed reduced basal level expression of ureA when arsS was absent. Additionally, we determined that both HpNikR and HpArsRS were necessary for maximal expression of ureA under nickel, low pH and combined nickel and low pH stresses. In vitro studies of HpArsR-P with the P-ureA DNA target using florescence anisotropy confirmed a direct protein/DNA binding interaction. Together, these data support a model in which HpArsRS and HpNikR cooperatively interact to regulate ureA transcription under various environmental conditions. This is the first time that direct cross-talk between HpArsRS and HpNikR at neutral pH has been demonstrated

Local adaptations to frost in marginal and central populations of the dominant forest tree Fagus sylvatica L. as affected by temperature and extreme drought in common garden experiments

Local adaptations to environmental conditions are of high ecological importance as they determine distribution ranges and likely affect species responses to climate change. Increased environmental stress (warming, extreme drought) due to climate change in combination with decreased genetic mixing due to isolation may lead to stronger local adaptations of geographically marginal than central populations. We experimentally observed local adaptations of three marginal and four central populations of Fagus sylvaticaL., the dominant native forest tree, to frost over winter and in spring (late frost). We determined frost hardiness of buds and roots by the relative electrolyte leakage in two common garden experiments. The experiment at the cold site included a continuous warming treatment; the experiment at the warm site included a preceding summer drought manipulation. In both experiments, we found evidence for local adaptation to frost, with stronger signs of local adaptation in marginal populations. Winter frost killed many of the potted individuals at the cold site, with higher survival in the warming treatment and in those populations originating from colder environments. However, we found no difference in winter frost tolerance of buds among populations, implying that bud survival was not the main cue for mortality. Bud late frost tolerance in April differed between populations at the warm site, mainly because of phenological differences in bud break. Increased spring frost tolerance of plants which had experienced drought stress in the preceding summer could also be explained by shifts in phenology. Stronger local adaptations to climate in geographically marginal than central populations imply the potential for adaptation to climate at range edges. In times of climate change, however, it needs to be tested whether locally adapted populations at range margins can successfully adapt further to changing conditions

The Grizzly, October 23, 1987

Middle States to Evaluate the Ursinus Community • Gilmore Tops Successful Homecoming • Greek Life Threatened • Letters: Pledging Restrictions Destructive?; Professor Supports Religious Understanding • Hot Entertainment to Hit Ursinus • As We Begin the World • Dance Forum Dazzles Audience • Scholars Offer Variety • Old Wine in New Bottles • Speech Exam Offered • Surf\u27s Up for the Lady Bears • Ursinus Athletes and Coach Win at Homecoming • This Run\u27s for you Vince • Athlete of the Week: Football\u27s Glenn Worgan • Grizzlies to Hang Tough • Choral Groups to Entertain Ursinus • WVOU is Back! • Ritter Center: A Beehive of Busyness the Busie Body to Premiere Oct. 29 • Owners Strike Backhttps://digitalcommons.ursinus.edu/grizzlynews/1197/thumbnail.jp

The Grizzly, February 5, 1988

Cavorting Cop Caught • Lewis Disclaims Labels at Forum • Rock\u27N America • Patterns Campaign Nears Completion • Hockey Held as Hokey • Contra-versial Censorship Irks Student • History Department Interviews a New Way • Concert Features Christian Music • Summer Study in France a Fun-do • Notes: R.A. Rap Session Announced; Presidency Probers Convene; ALF Re-runs Rewarding; Child Safety Course Offered • Men\u27s Hoopsters Suffer Temporary Setback • Track Team Making Great Strides • Record Books Rewritten • U.C. Matters: Wrestling Tough and Confident • Men \u27Mers Holding Their Ownhttps://digitalcommons.ursinus.edu/grizzlynews/1203/thumbnail.jp

Differences in size between first and replacement clutches match the seasonal decline in single clutches in Tree Swallows Tachycineta bicolor

© 2016 British Ornithologists' UnionThe seasonal decline in clutch size in birds can be a response to the environmentally conditioned decrease in prospects for offspring or a consequence of a lower physical ability of late-breeding females. To find out which of the explanations apply in Tree Swallows Tachycineta bicolor, we assessed whether replacement clutch size in this species is affected by an individual female's ability to lay a certain number of eggs. To do this, we measured the decline in clutch size as a function of laying date between first and replacement clutches in individuals that re-nested following natural failure, and compared this with the rate of decline in clutch size with laying date for Tree Swallows that laid only a single clutch in that season. Additionally, we assessed whether the clutch size and the rate of its seasonal decline varied across years. We accounted for the truncated and under-dispersed nature of clutch size data by using a Bayesian approach in the analysis. We found little variation in the rate of clutch size decline across years at our breeding site. Accounting for this seasonal decline in clutch size, mean clutch size was similar between single-time breeding females and those that laid replacement clutches, implying that the number of eggs laid on the second attempt by female Tree Swallows is determined by laying date, rather than by the female's physical ability to produce a clutch of a certain size

The Grizzly, October 7, 1988

Berman Art Center Breaks Ground • Pledging Undergoes Changes • Welcome Home Alumni! • Letter: Honor Code Discussion Revived • Giving Garbage the Dump • Jazz: Basie Style • Ursinus Presents: A Voice of My Own • On the Forum Front • Mistake Free Bears Get First Win • Field Hockey Making Gains • Soccer Gains Respect • Annual Run Offers Health and Fun • 1988 Homecoming Queen Candidates • Sherman Strutting Stuff • Intramural Results Announced • U.C. Welcomes Gilbert\u27s Enthusiasm • Cycling Club Returns • Campbell: Not Your Typical Bowl of Soup • Econ: Economopolis • Professor LoBue Introduces New Chemistry in Pfahler • Discover Discover! • U.C. Students Study Better Late Than Neverhttps://digitalcommons.ursinus.edu/grizzlynews/1219/thumbnail.jp

The relationship between the perception of distributed leadership in secondary schools and teachers' and teacher leaders' job satisfaction and organizational commitment

This study investigates the relation between distributed leadership, the cohesion of the leadership team, participative decision-making, context variables, and the organizational commitment and job satisfaction of teachers and teacher leaders. A questionnaire was administered to teachers and teacher leaders (n=1770) from 46 large secondary schools. Multiple regression analyses and path analyses revealed that the study variables explained significant variance in organizational commitment. The degree of explained variance for job satisfaction was considerably lower compared to organizational commitment. Most striking was that the cohesion of the leadership team and the amount of leadership support was strongly related to organizational commitment, and indirectly to job satisfaction. Decentralization of leadership functions was weakly related to organizational commitment and job satisfaction

The Grizzly, November 20, 1987

Outdoor Graduation Possible • Judo Flip Flopped • Kamens Won\u27t \u27Drink the Water\u27 • Akin Probes Goals for Middle States • Letters: Director of Security Concerned; Mail Malady; Physical Activity Needed • Myth Myths Explained in Fourth Forum • Messiah to Celebrate 50th Year • Volkmer Outshines Pooch? • Promising Season to Start for Basketball • Football Players make Conference Team • Lady \u27Mers Victorious • Grizzly Wrap Up • Lady Grizzlies Begin Season • Government Officials Speak at Conference • Bad Day for Team • Out of the States : Into Africa • Apartheid: The Economic Impact • The Attention-Getterhttps://digitalcommons.ursinus.edu/grizzlynews/1200/thumbnail.jp