impact of leadership styles on organizational forgetting of public and private hospitals in Tehran province:2010

Two major aspects of knowledge management for gaining competitive advantage in organizations are organizational learning and organizational forgetting. Despite several research studies on knowledge management and organizational learning, a few studies have been performed on organizational forgetting and its management. In this study, it was attempted to introduce a conceptual model of organizational forgetting and to investigate its relationship with change-oriented and pragmatic leadership styles. The present survey was of fundamental experimental type, based on correlation method adopting sampling technique. Managers and vice-chancellors of private and public hospitals in Tehran formed the population of this research. The data were analyzed by LISREL software using structural equation modeling. Although both leadership styles had an influence on purposeful organizational forgetting, change-oriented leadership appeared to be more effective. Furthermore, the effects of various variables on pragmatic leadership and change-oriented leadership were obtained separately. It was found that short-term thinking of the leader with a factor loading of 0.89 had the largest effect on pragmatic leadership and encouraging and inspiring of the leader with a factor loading of 0.92 had the largest effect on change-oriented leadership. Comparing the effects of change-oriented leadership and pragmatic leadership styles on purposeful organizational forgetting, the researchers suggest to apply change-oriented leadership style for optimal management of purposeful forgetting

[ effect of ocular dominance on stereoacuity in experimentally induced anisometropia]

To evaluate the effect of ocular dominance on stereoacuity in experimentally induced anisometropia. In this clinical trial, 60 healthy adult volunteers 18-37 years of age [mean age: 25.58 years] without any ocular disease were enrolled at Tabriz Nikookari eye hospital over a one-year period. Anisometropia [unilateral myopia] was induced by placing trial lenses over the dominant and non dominant eyes in 1 diopter [D] increments ranging from 1-3 D. Stereoacuity was measured using the TNO, Randot and Titmus stereotests and values were converted into Neperian logarithm [ln] and compared between the two eyes. Of sixty adults including, 25 male and 35 female subjects, the right eye was dominant in 49 [81.7%] of cases. Stereoacuity levels were reduced proportionate to the degree of anisometropia in all participants. Mean stereoacuity was 4.3, 5.5 and 7.4 ln for dominant eyes and 4.1, 5.4 and 7.3 ln for non dominant eyes usig the TNO test by applying 1, 2 and 3 D lenses, respectively [P>0.05]. Corresponding values were 3.5, 4.6 and 6.6 ln for dominant eyes and 3.4, 4.6 and 6.5 ln for non dominant eyes by the circles subcategory of Randot test, respectively [P>0.05]. The scores were 3.8, 4.7 and 6.5 ln for dominant eyes and 3.8, 4.7 and 6.4 ln for non dominant eyes by the circles subcategory of Titmus test, respectively [P>0.05]. Experimentally induced anisometropia could reduce stereoacuity. However, ocular dominance has no effect on the amount of stereoacuity reduction

[Prevalence and characteristics of accommodative esotropia at nikookari eye center form 2004 to 2009]

To study the prevalence and characteristics of accommodative esotropia [AET]. In a descriptive analytic study records of all patients referred from 1383 to 1388 to the strabismus clinic at Nikookari Eye Center were reviewed and demographic data such as age, gender, refractive error, type of AET, mean deviation and amblyopia were analyzed. A total of 2,146 patients were referred during this period. AET comprised 142 [11.55%] patients. 35.9% of these patients were male and 64.1% were female. Mean age at presentation was 5.85 +/- 4.4 years. The frequency of refractive accommodative ET [RAET], non-refractive accommodative ET [NRAET], partially accommodative ET [PAET] were 82 [57.7%], 7 [4.9%] and 53 [37.3%], respectively. Overall, 69 [48.6%] patients were amblyopic and spherical equivalent refractive error was +4.22 +/- 1.82 D. Inferior oblique overaction [IOOA] and dissociated vertical deviation [DVD] were seen in 5 [3.5%] and 2 [1.4%] of patients respectively. RAET is the most common and NRAET is the least common form of AET. Amblyopia is common in AET. The prevalence of associated findings such as DVD and IOOA is low

[Surgical outcomes of partially accommodative esotropia]

To determine the surgical results of partially accommodative esotropia [PAET]. Thirty-eight patients with PAET scheduled for surgery from 2002 to 2008 were enrolled in a descriptive, analytic retrospective study. Patient characteristics including age, gender, refractive error, visual acuity, pre and post operative deviation, technique of surgery and follow up duration were recorded and analyzed. PAET accounted for 38.29% of accommodative esotropia. Mean age and refractive error [spherical equivalent] were 6.32 +/- 3.38 years and +4.1 +/- 1.98 diopters, respectively. The prevalence of amblyopia was 54.04% and patients were followed up for 18.76 +/- 13.58 months. Mean pre and post operative deviation were 30.87 +/- 10.3 and 2.05 +/- 5.7 PD, respectively [P< 0.001]. Mean amount of bilateral medial rectus recession was 5.48 +/- 0.66 mm. In 78.9% of patients, postoperative deviation was within 10PD of orthotropia. Residual esotropia and consecutive exotropia were seen in 18.4% and 2.6% of patients, respectively. Pre-operative deviation, refractive error and amblyopia had no significant effect on outcomes of surgery

[Outcomes of bicanalicular silicone intubation for congenital nasolacrimal duct obstruction]

To evaluate the success rate of bicanalicular silicone tube intubation in children with congenital nasolacrimal duct obstruction [CNLDO]. Hospital records of 71 cases of bicanalicular silicone intubation in 62 children with CNLDO were reviewed. Success was defined as resolution of symptoms and signs such as epiphora and discharge 6 months after removal of the silicone tube. Mean age was 3.64 +/- 1.8 [range 1.4-9.5] years. Mean duration of intubation was 6.0 +/- 4.8 [range 1-30] months. The overall success rate was 85.9% including 87.5% for primary and 84.2% for secondary procedures. There was no significant change in success rate of primary [P= 0.09] or secondary [P= 0.13] procedures with increasing age. Intubation duration greater than 6 months was not associated with increasing success rate [P=0.51]. Pre-planned removal of tubes [<3 months] because of dislodgement occurred in 4 eyes [5.6%] but had no significant effect on success rate [P=0.09]. Bicanalicular silicone intubation is an effective treatment for children with CNLDO at any age. Duration of intubation greater than 6 months does not improve the success rate. Pre-planned removal of the tube [<3 months] because of dislodgement is the most common complication but does not seem to increase the risk of failure

[Comparison of excyclotorsion induced by two surgical methods in rabbit eyes]

Compaison of excyclotorsion induced by horizontal transposition of vertical rectus muscles versus vertical transposition of horizontal rectus muscles in rabbit eyes. In this exprimental study, group 1 underwent full tendon nasal transposition of the superior rectus and full tendon temporal transposition of the inferior rectus [10 adult rabbits]; group 2 underwent superior transposition of the lateral rectus and inferior tranposition of the medical rectus [10 adult rabbits]. External limbal marking was used to estimate the magnitude of excyclotorsion resulting from muscle surgery. The mean angle of excyclotorsion in group 1 was 31 +/- 1.8 degree, ranging from 28-35 degree. The mean angle of excyclotorsion in group 2 was 12.85 +/- 1.6 degree, ranging from 10-16 degree. Excyclotorsion induced by horizontal transposition of vertical rectus muscles was significantly larger than that induced by vertical transposition of horizontal rectus muscles [P<0.001]. The amount of excyclotorsion after LR displacement [1.1 +/- 0.8 degree] was significantly smaller than the amount of excyclotorsion after MR displacement [12.6 +/- 1.7 degree] [P<0.001]. Althaugh the mean angle of excyclotorsion induced by horizontal transposition of vertical rectus muscles was larger than that of vertical transposition of horizontal rectus muscles, superior displacement of the LR muscle induced no significant change in globe torsion. The torsional effect of horizontal transposition of vertical rectus muscles can be changed varying amounts of globe torsion