1,721,510 research outputs found
Microkeratome-assisted preparation of ultrathin grafts for descemet stripping automated endothelial keratoplasty
No full textPURPOSE. To compare three microkeratome-assisted techniques for the preparation of ultrathin (UT) grafts for Descemet stripping automated endothelial keratoplasty. METHODS. After dissection with a 300-Î1⁄4m microkeratome head in 40 donor tissues, a second cut was performed with a 130-Î1⁄4m head either after manual stromal hydration (group A, n = 10) or osmotic hydration at the eye bank (group B, n = 10) or with a 50- or 90-Î1⁄4m head, depending on residual bed thickness (group C, n = 10); no further dissection was performed in the control group (group D, n =Î1⁄4 10). Corneal thickness and endothelial cell (EC) count were determined at all appropriate stages. Statistical analysis was performed using a Fisher exact test. RESULTS. Final graft thicknesses in groups A (89.1 ± 34.1Î1⁄4m), B (84.1 ± 18.6 Î1⁄4m), and C (72.1 ± 10.1 Î1⁄4m) were significantly lower than in group D (201.9 ± 25.3 Î1⁄4m) (P < 0.001). EC loss did not differ significantly among the groups. Multiple areas of Descemet detachment were seen in 4 of 10 corneas of group A. CONCLUSIONS. All methods proved equally efficient in producing UT grafts, but stromal hydration induced tissue structural changes. EC loss was unaffected by the additional manipulation required to prepare UT grafts. © 2012 The Association for Research in Vision and Ophthalmology, Inc
Vasudhara Adivasi Dairy Cooperative: Model for the Second White Revolution?
No full textIndia's White Revolution has made the country the largest milk producer in the world, but this has bypassed the Adivasi heartland of the central Indian plateau. The Vasudhara cooperative, which has organised 1,20,000 mostly Adivasi women from Valsad, Navsari, Dang and Dhule districts into a Rs 1,000-crore dairy business, provides a model for India's second White Revolution designed to empower Adivasi women
Vasudhara Adivasi Dairy Cooperative: Model for the Second White Revolution?
No full textIndia's White Revolution has made the country the largest milk producer in the world, but this has bypassed the Adivasi heartland of the central Indian plateau. The Vasudhara cooperative, which has organised 1,20,000 mostly Adivasi women from Valsad, Navsari, Dang and Dhule districts into a Rs 1,000-crore dairy business, provides a model for India's second White Revolution designed to empower Adivasi women
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Transcorneal Suture Fixation of Posterior Lamellar Grafts in Eyes With Minimal or Absent Iris–Lens Diaphragm
No full textPurpose: To describe a technique that uses a transcorneal suture for safe delivery and fixation of donor tissue during Descemet stripping automated endothelial keratoplasty in patients that are at risk of graft dislocation into the vitreous cavity as a result of minimal or absent iris-lens diaphragm. • Design: Interventional case series. Methods: Thirteen eyes with endothelial decompensation and inadequate iris-lens diaphragm underwent modified Descemet stripping automated endothelial keratoplasty surgery. A 10-0 Prolene suture (Ethicon Inc) was passed through the endothelial graft and used to pull the graft into the eye and anchor it onto the recipient cornea. Best-corrected visual acuity, refraction, and complications were recorded. Results: Preoperative best-corrected visual acuity was less than 20/200 in all cases. Eleven patients had a pre-existing comorbidity (glaucoma, n = 8; previous retinal detachment, n = 2; epiretinal membrane n = 1). Average follow-up was 11.3 months (range, 3 to 36 months). No graft dislocation occurred during surgery. After surgery, graft detachment was noted in 2 cases and rebubbling succeeded in achieving reattachment. All patients had successful attachment of the endothelial graft. Postoperative best-corrected visual acuity improved in 11 of 13 patients and remained unchanged in 2 patients. Conclusions: In patients with insufficient iris-lens diaphragm, this technique allowed safe graft delivery, prevented intraoperative and postoperative graft dislocation, and facilitated successful rebubbling in case of postoperative graft detachment
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Pneumatic dissection and storage of donor endothelial tissue for Descemet's membrane endothelial keratoplasty: A novel technique
No full textPurpose: To investigate the feasibility of pneumatic dissection of donor endothelium and the effect of 7 days of storage in tissue culture medium on the endothelial cell count. Design: Experimental study. Participants: We used 20 human donor corneoscleral tissues deemed unsuitable for transplantation. Intervention: Donor corneas were mounted on an artificial anterior chamber and the anterior stroma removed with a 300-micron microkeratome head. Air was injected into the residual donor tissue with a 30-G needle from the endothelial side to detach Descemet's membrane. The "bubble" was expanded as far as possible into the periphery. A silicone weight was attached to the scleral ring and the prepared tissue was stored in tissue culture medium for 7 days. Main Outcome Measures: Complete detachment of Descemet's membrane, size of detachment, pre- and post-storage endothelial cell counts. Results: Complete detachment of Descemet's membrane was achieved in 19 of 20 (95%) cases. In 12 (60%) cases, this was achieved with a single injection; 7 (35%) cases required repeat injections. In 1 case, Descemet's membrane could not be detached despite repeat air injections. The average size of detachment was 8.11±2.0 mm. Endothelial cell loss after 7 days of tissue culture medium storage was 4.44±4.3%. Conclusions: Descemet's membrane and endothelium can be separated from the overlying stroma with a simple technique using air dissection. An adequate size of graft tissue is obtained without the need to manually handle the tissue. The technique allows storage of the tissue in tissue culture medium with low endothelial cell loss
Objective selection of short-axis slices for automated quantification of left ventricular size and function by cardiovascular magnetic resonance
Full text linkBackground: Quantification of left ventricular (LV) volume from cardiovascular magnetic resonance images relies on subjective and often challenging selection of short-axis (SAX) slices. We hypothesized that this could be solved by defining mitral annular (MA) plane and apex in long-axis (LAX) views, which could be combined with automated LV volume analysis that does not rely on manual tracing of the endocardial border. Methods: SAX images from 50 subjects were analyzed using custom software. LV apex and insertion points of the mitral leaflets were marked on LAX views and used to approximate MA plane. End-systolic and end-diastolic LV volumes (ESV, EDV) were measured while including only slices or their parts located between MA plane and LV apex. Endocardial borders were automatically detected using our previously validated algorithm and also manually traced to obtain reference values. Results: Selection of anatomic landmarks in LAX views allowed automated measurement of LV volumes without the need for subjective slice selection. Intertechnique comparisons resulted in high correlations (EDV: r. = 0.95; ESV: r. = 0.96) and small biases (1 and 9 ml). Combined three-dimensional displays of LAX and SAX views with the MA plane showed that in 7/10 worst cases, intertechnique discordance was due to incorrect manual tracing at LV base that erroneously included part of atrial cavity in LV volume or excluded part of LV cavity, i.e., incorrect reference values. Conclusion: Defining the MA plane and apex in the LAX views obviates the need for subjective slice selection and eliminates errors in LV volume measurements
- …
