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Sample records for stripping endothelial keratoplasty

  1. Topographic characteristics after Descemet's membrane endothelial keratoplasty and Descemet's stripping automated endothelial keratoplasty.

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    Takahiko Hayashi

    Full Text Available To investigate the topographic characteristics of the posterior corneal surface after Descemet's endothelial membrane keratoplasty (DMEK and Descemet's stripping automated endothelial keratoplasty (DSAEK and their effects on postoperative visual acuity.Nineteen eyes of 19 patients after DMEK, 23 eyes of 23 patients after DSAEK, and 18 eyes of 18 control subjects were retrospectively analyzed. Best spectacle-corrected visual acuity (BSCVA, aberration factors (higher-order aberrations [HOAs], spherical aberrations [SAs], and coma aberrations [Comas] at 6.0 mm were evaluated preoperatively and at 1, 3, and 6 months postoperatively. The posterior refractive pattern of the topography map was classified into 5 grades (0-5 (posterior color grade using anterior segment optical coherence tomography. Correlations between BSCVA and some factors (abbreviation factors, posterior color grade were analyzed.BSCVA was significantly better after DMEK than after DSAEK (P < 0.001. Posterior HOAs, SAs, and Comas after each type of endothelial keratoplasty were significantly greater compared to control (P < 0.01. Posterior HOAs, total/anterior/posterior SAs, and posterior color grade were significantly lower in the DMEK group than in the DSAEK group at 3 months (P < 0.024 [posterior HOAs], P = 0.047 [total SA], P < 0.001 [anterior SAs], P = 0.021 [posterior SAs], and P < 0.001 [posterior color grade] and 6 months postoperatively (P = 0.034 [posterior HOAs], P < 0.001 [total SAs], P < 0.001 [anterior SAs], P = 0.013 [posterior SAs], and P = 0.004 [posterior color grade]. BSCVA was significantly correlated with HOAs, SAs, and posterior color grade (P < 0.001 for all except anterior HOAs [P = 0.004].High posterior color grades were associated with larger aberration factors and had a negative effect on visual function after endothelial keratoplasty. Rapid improvement of visual function after DMEK may be attributed to less change at the posterior surface.

  2. Descemet's stripping endothelial keratoplasty under failed penetrating keratoplasty: visual rehabilitation and graft survival rate.

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    Anshu, Arundhati; Price, Marianne O; Price, Francis W

    2011-11-01

    To evaluate graft survival, risk factors for failure, complications, and visual rehabilitation in patients who underwent Descemet's stripping endothelial keratoplasty (DSEK) under a failed penetrating keratoplasty (PK). Retrospective interventional case series. Sixty eyes (60 patients) treated at Price Vision Group, Indianapolis, Indiana. Graft diameters ranged from 8 to 9 mm and were ∼1 mm larger than the previous PK. The Descemet's membrane was not stripped in the majority (54, 84%). The graft was inserted using forceps or a Busin funnel glide (Moria, Anthony, France). The probability of graft survival was calculated by Kaplan-Meier survival analysis. Graft survival, best-corrected visual acuity (BCVA), and complications. The mean recipient age was 68 years (range, 17-95 years). Forty eyes had 1 previous failed PK, 14 eyes had 2 previous failed PKs, and 6 eyes had 3 previous failed PKs. Thirty-one eyes (52%) had preexisting glaucoma, and 16 eyes (27%) had prior glaucoma surgery (trabeculectomy in 4, shunt procedure in 12). Fifty-five grafts were performed for visual rehabilitation, and 5 grafts were performed for pain relief. Median follow-up was 2.3 years (range, 2 months to 6 years). Median preoperative BCVA was 1.23 logarithm of the minimum angle of resolution (logMAR) (range, 0.2-3, Snellen 20/340), and median postoperative visual improvement was 0.6 logMAR (6 lines), range -0.3 to +2.7. Four eyes had graft detachment (6.6%), 7 eyes (10.5%) had endothelial rejection, and 10 eyes (16.6%) had graft failure (primary failure in 2, secondary failure in 8). The overall secondary graft survival rates were 98%, 90%, 81%, and 74% at 1, 2, 3, and 4 years, respectively. Prior glaucoma shunt was the principal risk factor for graft failure. The graft survival rates were 100%, 96%, 96%, and 96% in eyes without a prior shunt versus 93%, 74%, 44%, and 22% with a prior shunt at 1, 2, 3, and 4 years, respectively (P=0.0005; relative risk = 20). Peripheral anterior synechiae

  3. Descemet stripping endothelial keratoplasty: One-year follow-up

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    Nikolić Ljubiša

    2010-01-01

    Full Text Available Introduction. Sutureless transplantation of endothelium on a thin stromal carrier was introduced under the name of Descemet stripping endothelial keratoplasty (DSEK in 2004. It has become the treatment of choice of corneal oedema due to endothelial dysfunction. Objective. To investigate posterior lamellar graft attachment, central corneal thickness (CCT, astigmatism, and best corrected visual acuity (BCVA during one-year follow-up. Methods. Surgery was performed on one eye of 11 patients with pseudophakic bullous keratopathy and Fuchs’ dystrophy. The graft thick 150-200 μm and 8.0 mm in diameter was detached manually. The carrier of the recipient cornea was created by DSEK. The graft was folded in half, introduced into the anterior orbital chamber through a 5.0 mm cut on the limbus and attached by air bubble along the internal side of the recipient cornea. CCT and astigmatism were evaluated by corneal topography, and graft attachment by biomicroscopy. Results. One year after surgery, all grafts remained attached. Primary graft failure occurred in three eyes, probably due to the crushing effect of the forceps. BCVA was 20/30 (2 eyes, and 20/40 (6 eyes, CCT 643-728 μm, and astigmatism 1.1 D to 2.9 D. The peak values were reached three months after surgery, and did not change much afterwards. Conclusion. This is the first report on the long-term results of DSEK in our literature. The results are similar to those obtained by more experienced DSEK surgeons, and suggest that this procedure is safe and successful.

  4. Donor disc attachment assessment with intraoperative spectral optical coherence tomography during descemet stripping automated endothelial keratoplasty

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    Edward Wylegala

    2013-01-01

    Full Text Available Optical coherence tomography has already been proven to be useful for pre- and post-surgical anterior eye segment assessment, especially in lamellar keratoplasty procedures. There is no evidence for intraoperative usefulness of optical coherence tomography (OCT. We present a case report of the intraoperative donor disc attachment assessment with spectral-domain optical coherence tomography in case of Descemet stripping automated endothelial keratoplasty (DSAEK surgery combined with corneal incisions. The effectiveness of the performed corneal stab incisions was visualized directly by OCT scan analysis. OCT assisted DSAEK allows the assessment of the accuracy of the Descemet stripping and donor disc attachment.

  5. Evolution of endothelial keratoplasty.

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    Price, Francis W; Price, Marianne O

    2013-11-01

    Endothelial keratoplasty has evolved into a popular alternative to penetrating keratoplasty (PK) for the treatment of endothelial dysfunction. Although the earliest iterations were challenging and were not widely adopted, the iteration known as Descemet stripping endothelial keratoplasty (DSEK) has gained widespread acceptance. DSEK combines a simplified technique for stripping dysfunctional endothelium from the host cornea and microkeratome dissection of the donor tissue, a step now commonly completed in advance by eye bank technicians. Studies show that a newer endothelial keratoplasty iteration, known as Descemet membrane endothelial keratoplasty (DMEK), provides an even faster and better visual recovery than DSEK does. In addition, DMEK significantly reduces the risk of immunologic graft rejection episodes compared with that in DSEK or in PK. Although the DMEK donor tissue, consisting of the bare endothelium and Descemet membrane without any stroma, is more challenging to prepare and position in the recipient eye, recent improvements in instrumentation and surgical techniques are increasing the ease and the reliability of the procedure. DSEK successfully mitigates 2 of the main liabilities of PK: ocular surface complications and structural problems (including induced astigmatism and perpetually weak wounds), whereas DMEK further mitigates the 2 principal remaining liabilities of PK: immunologic graft reactions and secondary glaucoma from prolonged topical corticosteroid use.

  6. [Endothelial keratoplasty: Descemet stripping (DSEK) using TAN EndoGlide™ device: case series].

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    Pazos, Henrique Santiago Baltar; Pazos, Paula Fernanda Morais Ramalho Baltar; Nogueira Filho, Pedro Antônio; Grisolia, Ana Beatriz Diniz; Silva, André Berger Emiliano; Gomes, José Álvaro Pereira

    2011-01-01

    To report the results of Descemet stripping endothelial keratoplasty (DSEK) using the TAN EndoGlideTM device to facilitate the insertion of the endothelial membrane. Prospective clinical study that included nine patients presenting corneal edema secondary to endothelial dysfunction. Best corrected visual acuity, refraction, central corneal thickness, endothelial cell density and complications were analyzed after a six-month follow-up. There was a significant improvement in the corneal edema and visual acuity in 7 patients (77.78%). The best corrected visual acuity ranged between 20/40 and 20/200. The average density of endothelial cells in six months varied between 1,305 cells/mm² and 2,346 cells/mm² with an average loss of 33.14% cells. Detachment of part of the graft was observed in one eye (11.11%) and primary failure of the endothelial transplantation occurred in 2 eyes (22.22%). The device TAN EndoGlideTM facilitates the introduction of the graft in Descemet stripping endothelial keratoplasty.

  7. Non-Descemet’s stripping automated endothelial keratoplasty for bullous keratopathy secondary to iridoschisis

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    Minezaki T

    2013-07-01

    Full Text Available Teruumi Minezaki, Takaaki Hattori, Hayate Nakagawa, Shigeto Kumakura, Hiroshi GotoDepartment of Ophthalmology, Tokyo Medical University, Shinjukuku, Tokyo, JapanPurpose: To report a case of bullous keratopathy secondary to iridoschisis treated by non-Descemet's stripping automated endothelial keratoplasty (nDSAEK.Case report: A 79-year-old woman was referred to our hospital with loss of vision in the left eye. Slit lamp examination of her left eye showed a shallow anterior chamber with cataract and schisis in the inferior quadrant of iris stroma. Bullous keratopathy secondary to iridoschisis was diagnosed. Cataract surgery with iridectomy succeeded to deepen the anterior chamber and remove the floating iris leaf, although corneal edema remained. Four days later, nDSAEK was performed, which resolved corneal edema and restored visual acuity.Conclusion: The two-step surgery of cataract surgery plus iridectomy followed by nDSAEK may be an effective strategy for treating bullous keratopathy secondary to iridoschisis.Keywords: iridoschisis, bullous keratopathy, non-Descemet's stripping automated endothelial keratoplasty

  8. Microsporidial infection masquerading as graft rejection post-Descemet's stripping automated endothelial keratoplasty

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    Lumbini Devi

    2017-01-01

    Full Text Available A 51-year-old immunocompetent male with a history of Fuchs' endothelial dystrophy and immature cataract who underwent Descemet's stripping automated endothelial keratoplasty with intraocular lens implantation in both eyes presented with redness and defective vision of 1-day duration in his left eye. Slit lamp examination revealed coarse superficial punctate lesions with graft edema. He was diagnosed with acute graft rejection and treated with topical steroids. Two days later, symptoms worsened in his left eye with the involvement of his right eye showing a similar clinical picture. An infectious etiology was suspected and in vivo confocal microscopy ordered, which revealed hyperreflective dots, highly suggestive of microsporidial spores. The patient was prescribed topical fluconazole 0.3% in both eyes. This unique presentation of bilateral graft edema following microsporidial keratoconjunctivitis in postgraft patients requires a high index of suspicion as it can be easily be mistaken for and mismanaged as acute graft rejection.

  9. Graft Suturing for Lenticule Dislocation after Descemet Stripping Automated Endothelial Keratoplasty

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    Wai-Kwan Wu

    2011-01-01

    Full Text Available Purpose: To report the mid-term outcomes of graft suturing in a patient with lenticule dislocation after Descemet stripping automated endothelial keratoplasty (DSAEK. Case Report: A 78-year old woman was found to have graft dislocation involving the nasal half of the cornea after uneventful DSAEK. Graft repositioning, refilling the anterior chamber with air, and placement of four full-thickness 10/0 nylon sutures over the detached area were performed two weeks after the initial surgery. The sutures were removed 6 weeks later. Serial specular microscopy and anterior segment optical coherence tomography were performed. At 18 months, there was good lenticule apposition and a clear graft. Conclusion: Anchoring sutures seem to be effective for management of graft detachment following DSAEK.

  10. Toxic Anterior Segment Syndrome following a Triple Descemet’s Stripping Automated Endothelial Keratoplasty Procedure

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    Nir Sorkin

    2012-11-01

    Full Text Available Purpose: To present a unique case of a 58-year-old female with toxic anterior segment syndrome (TASS, following a triple procedure: Descemet’s stripping automated endothelial keratoplasty (DSAEK, phacoemulsification and posterior chamber intraocular lens implantation. Methods: The patient was treated with topical dexamethasone sodium phosphate 0.1% and topical atropine sulfate 1%. Due to a slow improvement in her clinical status, oral prednisone 1 mg/kg/day was added. Results: The anterior chamber reaction improved gradually, with tapering down of topical and oral treatment, until a complete resolution of the anterior chamber reaction was observed. Conclusions: Taking into account the estimated volume of DSAEK triple procedures performed worldwide, we would expect an annual incidence of several TASS cases, following triple DSAEK procedures. However, we were unable to find any such previous reports in the literature. This fact raises questions regarding the cause of reduced TASS incidence following triple DSAEK procedures.

  11. Changes in corneal sensation, epithelial damage, and tear function after descemet stripping automated endothelial keratoplasty.

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    Hirayama, Yumiko; Satake, Yoshiyuki; Hirayama, Masatoshi; Shimazaki-Den, Seika; Konomi, Kenji; Shimazaki, Jun

    2013-09-01

    To study the ocular surface changes in eyes after Descemet stripping automated endothelial keratoplasty (DSAEK) compared with those after penetrating keratoplasty (PKP). This prospective study compared the changes in 31 eyes of 28 patients who underwent DSAEK (DSAEK group) with those in 15 disease-matched eyes of 15 patients who underwent PKP (PKP group). Corneal epithelial integrity was evaluated using a fluorescein staining score. Corneal sensation was measured with a Cochet-Bonnet esthesiometer. Tear function was evaluated using the Schirmer test, tear clearance test, tear function index, and tear break-up time. The postoperative fluorescein staining score was significantly higher in the PKP group than in the DSAEK group (P = 0.02). Postoperative corneal sensation was significantly better in the DSAEK group than in the PKP group (P sensation after DSAEK was significantly better than the preoperative value (P = 0.02). There were no statistically significant changes in the Schirmer test, tear clearance test, tear function index, or break-up time before and after the surgery in both the DSAEK and PKP groups. No significant differences were observed between the DSAEK and PKP groups after the surgery. Corneal sensation was preserved, and epithelial damage was less severe after DSAEK compared with PKP. Preservation of corneal sensation may contribute to the early recovery of visual function and long-term maintenance of ocular surface health after DSAEK.

  12. Nomogram to Predict Graft Thickness in Descemet Stripping Automated Endothelial Keratoplasty: An Eye Bank Study.

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    Bae, Steven S; Menninga, Isaac; Hoshino, Richard; Humphreys, Christine; Chan, Clara C

    2018-01-25

    The purpose of this study was to develop a nomogram to predict postcut thickness of corneal grafts prepared at an eye bank for Descemet stripping automated endothelial keratoplasty (DSAEK). Retrospective chart review was performed of DSAEK graft preparations by 3 experienced technicians from April 2012 to May 2017 at the Eye Bank of Canada-Ontario Division. Variables collected included the following: donor demographics, death-to-preservation time, death-to-processing time, precut tissue thickness, postcut tissue thickness, microkeratome head size, endothelial cell count, cut technician, and rate of perforation. Linear regression models were generated for each microkeratome head size (300 and 350 μm). A total of 780 grafts were processed during the study period. Twelve preparation attempts resulted in perforation (1.5%) and were excluded. Mean precut tissue thickness was 510 ± 49 μm (range: 363-670 μm). Mean postcut tissue thickness was 114 ± 22 μm (range: 57-193 μm). Seventy-nine percent (608/768) of grafts were ≤130 μm. The linear regression models included precut thickness and donor age, which were able to predict the thickness to within 25 μm 80% of the time. We report a nomogram to predict thickness of DSAEK corneal grafts prepared in an eye bank setting, which was accurate to within 25 μm 80% of the time. Other eye banks could consider performing similar analyses.

  13. Air-Assisted Descemet Stripping Automated Endothelial Keratoplasty with Posterior Chamber Fixation of an Aphakic Iris‑Claw Lens

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    Farid Karimian

    2010-01-01

    Full Text Available Endothelial keratoplasty (EK is the most exciting recent development in corneal transplantation. It has experienced surprisingly rapid growth in a very short period of time. One of the indications for EK is pseudophakic bullous keratopathy. However, concomitant intraocular lens (IOL exchange, if indicated, may prove challenging. Some surgeons routinely perform IOL exchange with a scleral-fixated posterior chamber IOL, together with Descemet′s stripping endothelial keratoplasty (DSEK; however, this combined procedure is time-consuming, difficult and fraught with complications. Another option is aphakic Artisan IOL fixation, but this is usually not acceptable because of the increased risk of endothelial cell loss and difficulty in filling the anterior chamber with the air bubble. Herein, we introduce a new technique for IOL exchange with an aphakic Artisan IOL fixated posterior to the iris, combined with DSEK. This surgical technique was designed to preserve anterior segment anatomic features as much as possible.

  14. Cost Minimization Analysis of Precut Cornea Grafts in Descemet Stripping Automated Endothelial Keratoplasty.

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    Yong, Kai-Ling; Nguyen, Hai V; Cajucom-Uy, Howard Y; Foo, Valencia; Tan, Donald; Finkelstein, Eric A; Mehta, Jodhbir S

    2016-02-01

    Descemet stripping automated endothelial keratoplasty (DSAEK) is the most common corneal transplant procedure. A key step in the procedure is preparing the donor cornea for transplantation. This can be accomplished via 1 of 3 alternatives: surgeon cuts the cornea on the day of surgery, the cornea is precut ahead of time in an offsite facility by a trained technician, or a precut cornea is purchased from an eye bank. Currently, there is little evidence on the costs and effectiveness of these 3 strategies to allow healthcare providers decide upon the preferred method to prepare grafts.The aim of this study was to compare the costs and relative effectiveness of each strategy.The Singapore National Eye Centre and Singapore Eye Bank performed both precut cornea and surgeon-cut cornea transplant services between 2009 and 2013.This study included 110 subjects who received precut cornea and 140 who received surgeon-cut cornea. Clinical outcomes and surgical duration were compared across the strategies using the propensity score matching. The cost of each strategy was estimated using the microcosting and consisted of facility costs and procedural costs including surgical duration. One-way sensitivity analysis and threshold analysis were performed.The cost for DSAEK was highest for the surgeon-cut approach ($13,965 per procedure), followed by purchasing precut corneas ($12,659) and then setting up precutting ($12,421). The higher procedural cost of the surgeon-cut approach was largely due to the longer duration of the procedure (surgeon-cut = 72.54 minutes, precut = 59.45 minutes, P cornea from eye bank. If there were more than 290 cases annually, the cheapest option would be to setup precutting facility.Our findings suggest that it is more efficient for centers that are performing a large number of cornea transplants (more than 290 cases) to set up their own facility to conduct precutting.

  15. Recurrent progressive anterior segment fibrosis syndrome following a descemet-stripping endothelial keratoplasty in an infant with congenital aniridia

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    Mihir Kothari

    2014-01-01

    Full Text Available Progressive anterior segment fibrosis syndrome (ASFS, after intraocular surgery in older children (≥9 years and adults with congenital aniridia, is described in the literature. In this report, we describe an unique case of ASFS in an infant with congenital aniridia following a combined trabeculotomy-ectomy and its recurrence after a descemet stripping endothelial keratoplasty. The ophthalmologists should be well aware of this entity and warn the parents about its possibilities. Use of immunomodulators or prolonged anti-inflammatory therapy may be considered to prevent its occurrence.

  16. Candida Endophthalmitis After Descemet Stripping Automated Endothelial Keratoplasty With Grafts From Both Eyes of a Donor With Possible Systemic Candidiasis.

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    Palioura, Sotiria; Sivaraman, Kavitha; Joag, Madhura; Sise, Adam; Batlle, Juan F; Miller, Darlene; Espana, Edgar M; Amescua, Guillermo; Yoo, Sonia H; Galor, Anat; Karp, Carol L

    2018-04-01

    To report 2 cases with late postoperative Candida albicans interface keratitis and endophthalmitis after Descemet stripping automated endothelial keratoplasty (DSAEK) with corneal grafts originating from a single donor with a history of presumed pulmonary candidiasis. Two patients underwent uncomplicated DSAEK by 2 corneal surgeons at different surgery centers but with tissue from the same donor and were referred to the Bascom Palmer Eye Institute with multifocal infiltrates at the graft-host cornea interface 6 to 8 weeks later, and anterior chamber cultures that were positive for the same genetic strain of C. albicans. Immediate explantation of DSAEK lenticules and daily intracameral and instrastromal voriconazole and amphotericin injections failed to control the infection. Thus, both patients underwent therapeutic penetrating keratoplasty with intraocular lens explantation, pars plana vitrectomy, and serial postoperative intraocular antifungal injection. Both patients are doing well at 2 years postoperatively with best-corrected vision of 20/20 and 20/30+ with rigid gas permeable lenses. One patient required repeat optical penetrating keratoplasty and glaucoma tube implantation 1 year after the original surgery. Literature review reveals that donor lenticule explantation and intraocular antifungals are often inadequate to control fungal interface keratitis, and a therapeutic graft is commonly needed. Interface fungal keratitis and endophthalmitis due to infected donor corneal tissue is difficult to treat, and both recipients of grafts originating from the same donor are at risk of developing this challenging condition.

  17. Effect of Intraocular Forward Scattering and Corneal Higher-Order Aberrations on Visual Acuity after Descemet's Stripping Automated Endothelial Keratoplasty.

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    Kazutaka Kamiya

    Full Text Available To assess the relationship of intraocular forward scattering and corneal higher-order aberrations (HOAs with best spectacle corrected visual acuity (BSCVA after Descemet's stripping automated endothelial keratoplasty (DSAEK, and to compare these parameters between DSAEK and non-Descemet's stripping automated endothelial keratoplasty (n-DSAEK groups.This retrospective study enrolled thirty eyes of 30 consecutive patients who underwent standard DSAEK, and who underwent successful phacoemulsification with intraocular lens implantation before DSAEK. The mean age at the time of surgery was 71.7 ± 10.4 years. We quantitatively evaluated the objective scattering index (OSI using the double-pass instrument (OQAS II, Visiometrics and corneal HOAs using Hartmann-Shack aberrometry (KR-9000PW, Topcon 3 months postoperatively.The mean OSI, corneal HOAs, and logMAR BSCVA 3 months after DSAEK were 7.91 ± 3.58, 0.43 ± 0.27 μm, and 0.32 ± 0.25, respectively. We found a significant correlation between the OSI and logMAR BSCVA (Spearman correlation coefficient r=0.714, p0.05.Our pilot study demonstrated that the postoperative corrected visual acuity was significantly correlated with intraocular forward scattering, but not with corneal HOAs in post-DSAEK eyes, suggesting that intraocular forward scattering plays a more essential role in postoperative visual performance than corneal aberrations after DSAEK. The detailed visual performance, such as HOAs and intraocular scattering, after n-DSAEK appears to be essentially equivalent to that after DSAEK.

  18. Long-Term Functional and Anatomical Outcome after Descemet Stripping Automated Endothelial Keratoplasty: A Prospective Single-Center Study

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    Jeroen van Rooij

    2018-01-01

    Full Text Available Purpose. To investigate the long-term anatomical and functional outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK. Methods. Prospective follow-up of 114 eyes (95 subjects after DSAEK for endothelial dysfunction. Measurements included best spectacle-corrected visual acuity (BSCVA, straylight, endothelial cell density (ECD, and graft thickness. Results. The mean follow-up time was 5.1 ± 1.5 years. Four grafts ultimately failed (after 5 to 7 years. From baseline up to 1 year after DSAEK, mean BSCVA improved by 0.30 logMAR. This beneficial effect remained until the last follow-up (LFU. After DSAEK, straylight was reduced. ECD sharply dropped by 900 cells/mm2 (33% immediately after surgery and, thereafter, steadily decreased at a rate of 11 cells/mm2 per month. No significant correlation was observed between graft thickness at 3 years and BSCVA. Conclusions. We observed a low graft failure rate and a normalization of graft thickness. Postoperative straylight remained elevated relative to the normal population. The sharp initial and the subsequent more gradual ECD decline are consistent with other studies. A significant and prolonged functional gain can be achieved by posterior lamellar grafting for endothelial dysfunction.

  19. Precut cornea for Descemet's stripping endothelial keratoplasty: experience at a single eye bank.

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    Mohamed, Ashik; Chaurasia, Sunita; Chandragiri, Venkataswamy; Kandhibanda, Srinivas; Gunnam, Srinivas; Garg, Prashant

    2017-06-01

    The aim of the study is to describe the experience with precut facility for endothelial keratoplasty at a single eye bank affiliated to a tertiary eye care center in India. Data on precut tissues from Nov 2012 to Dec 2014 were retrospectively reviewed from the electronic database of the eye bank of a tertiary eye care center in South India. Donor characteristic data including donor age, precut and postcut endothelial cell density (ECD), recipient age, and thickness of graft were collected. The number of precuts increased from 42 in 2012 (Nov and Dec) and 422 in 2013 to 584 in 2014. Of the total of 1048 precuts, seven (0.67 %) were miscut and could not be utilized for transplants. The donor age ranged from 2 to 89 years. A mean change of 43.6 ± 325.2 cells/mm 2 in ECD was noted after cut, proportional increase in mean being 1.9 %. The change in ECD after cut was negatively correlated with ECD before cut. The recipient age ranged from 1 to 89 years. The median thickness of donor lenticule after cut was 148 µm (interquartile range 131-166 µm). Analysis of precut donor corneas from a single eye bank shows that the ECD of the processed tissues was excellent for transplantation. The tissue wastage in the hands of eye bank personal was minimal.

  20. Descemet Stripping Endothelial Keratoplasty in a Patient with Keratoglobus and Chronic Hydrops Secondary to a Spontaneous Descemet Membrane Tear

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    Anton M. Kolomeyer

    2013-01-01

    Full Text Available Purpose. To report the use of Descemet stripping endothelial keratoplasty (DSEK in a patient with keratoglobus and chronic hydrops. Case Report. We describe a case of a 28-year-old man with bilateral keratoglobus and chronic hydrops in the right eye secondary to spontaneous Descemet membrane tear. The patient presented with finger counting (CF vision, itching, foreign body sensation, and severe photophobia in the right eye. Peripheral corneal thinning with central corneal protrusion and Descemet membrane tear spanning from 4 to 7 o'clock was noted on slit lamp examination. The right eye cornea was 15 mm in the horizontal diameter. After a 5.5-month loss to follow-up, the patient presented with discomfort, photophobia, decreasing vision, and tearing in the right eye. Vision was 20/60 with pinhole. 360-degree peripheral corneal ectasia with mild neovascularization and hydrops was present. Over the next few months, the patient complained of photophobia and intermittent eye pain. His vision deteriorated to CF, he developed corneal scarring with bullae, and a DSEK was performed. Eight months postoperatively, best-corrected vision improved to 20/30, cornea was clear, and the DSEK graft was stable. Conclusions. Nonresolving hydrops secondary to Descemet membrane tear in a patient with keratoglobus may result in permanent endothelial cell damage and scar formation. This may be successfully treated with DSEK.

  1. Endothelial keratoplasty: evolution and horizons

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    Gustavo Teixeira Grottone

    2012-12-01

    Full Text Available Endothelial keratoplasty has been adopted by corneal surgeons worldwide as an alternative to penetrating keratoplasty (PK in the treatment of corneal endothelial disorders. Since the first surgeries in 1998, different surgical techniques have been used to replace the diseased endothelium. Compared with penetrating keratoplasty, all these techniques may provide faster and better visual rehabilitation with minimal change in refractive power of the transplanted cornea, minimal induced astigmatism, elimination of suture-induced complications and late wound dehiscence, and a reduced demand for postoperative care. Translational research involving cell-based therapy is the next step in work on endothelial keratoplasty. The present review updates information on comparisons among different techniques and predicts the direction of future treatment.

  2. Visual acuity and intraocular pressure after Descemet's stripping endothelial keratoplasty in eyes with and without preexisting glaucoma.

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    Vajaranant, Thasarat S; Price, Marianne O; Price, Francis W; Gao, Weihua; Wilensky, Jacob T; Edward, Deepak P

    2009-09-01

    (1) To characterize the pattern of intraocular pressure (IOP) changes after Descemet's stripping endothelial keratoplasty (DSEK) in patients without preexisting glaucoma and in those with preexisting glaucoma, with and without prior glaucoma surgery. (2) To compare vision and IOP outcomes among the 3 groups. A retrospective chart review. A total of 805 DSEK cases performed in 641 patients by a single surgeon from December 2003 to August 2007 were available in the database. Only the first-treated eye of each patient with at least 1-year follow-up was included. Four hundred cases qualified: 315 eyes had no glaucoma (C); 64 eyes had glaucoma with no previous glaucoma surgery (G); and 21 eyes had prior glaucoma surgery (GS). Eyes with preexisting retinal problems were included in the analysis. Data analysis included calculation of incidence of postoperative IOP elevation. The study criteria for postoperative IOP elevation were IOP > or =24 mmHg or IOP increase > or =10 mmHg from baseline. Kruskal-Wallis test was used to compare visual acuity (VA) and IOP among the 3 groups preoperatively and at 1-, 3-, 6-, and 12-month postoperative visits. Visual acuity (Snellen) and IOP (millimeters of mercury). The incidence of postoperative IOP elevation by the study criteria was 35%, 45%, and 43% for groups C, G, and GS, respectively. Elevated IOP was medically managed by initiating or increasing glaucoma medications or reducing steroids in 27%, 44%, and 38% of the patients in groups C, G, and GS, respectively. A subsequent glaucoma procedure was performed in 0.3%, 5%, and 19% of patients in groups C, G, and GS, respectively. Only the control group had statistically significant IOP elevation at 12 months (median increase of 2 mmHg) when compared with baseline (Preferences.

  3. Results of Femtosecond Laser-Assisted Descemet Stripping Automated Endothelial Keratoplasty

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    Mohamed H. Hosny

    2017-01-01

    Full Text Available Purpose. To evaluate femtosecond laser in DSAEK surgery as an improvement to manual DSAEK. Settings. Department of Ophthalmology, Cairo University. Design. A retrospective observational clinical study. Methods. 20 eyes with SBK and Fuchs’ dystrophy underwent a Femto-assisted DSAEK by laser cutting of two matching posterior stromal discs in the recipient and donor corneas and then fitting the donor disc in the posterior corneal defect of the recipient using Busin’s glide or Terry forceps. Results. Corneal thickness decreased significantly from a mean of 900-micron preoperative values (900.7 m to 562 m postoperatively. Evidence of side healing was documented by OCT. One patient had a double AC, one patient had an air interface entrapment “Double Bubble,” one patient had a fungal infection and was treated by a therapeutic penetrating keratoplasty, and one patient had a CMO. Conclusion. Femtolaser-assisted DSAEK may be superior to manual techniques as it offers better centration, thinner graft/host complex, earlier corneal detergecense, and stronger healing. This study was registered at Researchregistry.com with a UID: researchregistry2274.

  4. A Method to Prepare a Descemet's Stripping Automated Endothelial Keratoplasty (DSAEK) Graft Using Donor Corneas With Narrow Scleral Rims: A Case Report.

    Science.gov (United States)

    Lin, Tzu-Yu; Hwang, Yih-Shiou; Ma, David Hui-Kang

    2015-09-01

    Donor corneas with narrow scleral rims are often disqualified for Descemet's Stripping Automated Endothelial Keratoplasty (DSAEK), mainly because of fluid leak and low pressure when they are mounted onto an artificial anterior chamber (AAC). This report describes a novel method to tight-lock a donor cornea with a narrow scleral rim so that microkeratome cutting is possible, allowing a DSAEK procedure to be completed. A 50-year-old male suffering from Epstein-Barr virus (EBV) endotheliitis with resulting corneal edema in his left eye was the subject of this study. His best corrected visual acuity (BCVA) was 20/600. The patient underwent a DSAEK procedure; however, the microkeratome cutting of the donor cornea initially failed due to its narrow scleral rim, which caused the balance salt solution (BSS) to leak out of the AAC. A doughnut-shaped cushion was made from a surgical glove, which enabled a tight lock of the cornea to the AAC, enabling the chamber pressure to be raised and the microkeratome cutting to be completed. A subsequent DSAEK procedure was performed uneventfully. Postoperatively, the patient received oral valganciclovir 450 mg b.i.d. to prevent EBV recurrence. The graft remained clear at 5 months post-op, and the patient's BCVA improved to 6/7.5. His endothelial count was 1830, which was ∼ 79% of the original value. Inserting a self-made cushion can enable donor corneas with narrow scleral rims to be used in DSAEK procedures and avoids unwanted switching from endothelial keratoplasty to penetrating keratoplasty (PKP).

  5. Endothelial keratoplasty: case selection in the learning curve.

    Science.gov (United States)

    O'Brien, Paul D; Lake, Damian B; Saw, Valerie P; Rostron, Chad K; Dart, John K; Allan, Bruce D

    2008-12-01

    Many corneal surgeons are making the transition from penetrating keratoplasty to endothelial keratoplasty techniques such as Descemet's stripping endothelial keratoplasty and Descemet's stripping automated endothelial keratoplasty in the routine treatment of corneal endothelial failure. Donor dislocation is the commonest complication of these newer techniques. We set out to determine whether preoperative lens/iris diaphragm integrity might influence the rate of donor dislocation and whether donor endothelial failure was more common after surgical intervention for donor dislocation. A retrospective multisurgeon comparative case series from a large teaching and referral center. Ninety-three eyes of 85 patients: consecutive cases of Descemet's stripping endothelial keratoplasty (n = 77) or Descemet's stripping automated endothelial keratoplasty (n = 16) performed between March 2004 and January 2007. A retrospective review of case notes. The number of eyes with an open communication between the anterior and posterior chambers (an iridectomy or lens capsular defect not covered by a posterior chamber intraocular lens), the number of eyes requiring surgical intervention to correct donor dislocation, and the number of eyes with donor endothelial failure within the follow-up period. Complete data sets were available for analysis in 89 eyes. The median follow-up interval at the time of the audit was 7 months (range 1-34 months). Donor dislocation was significantly more common (P = 0.017) in eyes with an open communication between the anterior and posterior chambers, occurring in 11 of 25 cases (44%) versus 12 of 64 cases (19%) with an intact iris/lens diaphragm. Early endothelial failure was significantly more common (P = 0.011) in cases requiring additional surgical intervention for donor dislocation, occurring in 6 of 21 cases (29%) after successful surgical reattachment of a dislocated donor disc versus 4 of 67 cases (6%) in which no additional intervention was required

  6. Challenges in pediatric endothelial keratoplasty

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    Vikas Mittal

    2014-01-01

    Full Text Available We performed endothelial keratoplasty (EK in three eyes of two siblings (2.5 years, male and 3.5 years, female with congenital hereditary endothelial dystrophy (CHED and report the intraoperative and postoperative difficulties. Repeated iris prolapse, apprehension of crystalline lens touch due to positive vitreous pressure, and need for frequent air injections to attach the graft were intraoperative challenges in all three eyes. These were addressed by use of Sheet′s glide instead of Busin′s glide during graft insertion and suturing of main and side ports before air injection. One eye had graft dislocation on second postoperative day due to eye rubbing by the child. Graft was repositioned with air and a venting incision was created. Postoperative examination required repeated general anesthesia. Corneal edema resolved completely in all three eyes. Present case series highlights the possible intraoperative and postoperative challenges and their solutions in pediatric EK for CHED.

  7. Modified Descemet’s Stripping Automated Endothelial Keratoplasty: The Use of Ophthalmic Viscoelastic Devices in Hypotonic Eyes That Had Undergone Glaucoma Filtering Surgeries

    Directory of Open Access Journals (Sweden)

    Itaru Oyakawa

    2018-01-01

    Full Text Available Purpose. Descemet’s stripping automated endothelial keratoplasty (DSAEK is more difficult in hypotonic eyes with filtering bleb, due to the difficulties in elevating the intraocular pressure (IOP. We report a new method that uses ophthalmic viscoelastic devices (OVDs to achieve good graft adhesion. Case Presentation. We performed modified DSAEK surgery on 2 eyes of 2 patients, who had previously undergone a trabeculectomy. Both eyes had functioning filtering blebs; the IOP was lower than 10 mmHg without medication. After the graft was inserted into the anterior chamber, the conjunctiva was penetrated, apart from the bleb, using a 30 G needle, and Healon V® was injected into the bleb until the encapsulated space was filled completely. Air was subsequently injected into the anterior chamber to promote the graft attachment to the back surface of the cornea. The IOP was elevated above 40 mmHg in both eyes 1 h after surgery and then decreased to less than 30 mmHg over the subsequent 3 h period. The implanted graft showed good adhesion and no dislocation. Conclusions. Our novel DSAEK procedure that adds one step of OVD injection into the filtering bleb may be useful for hypotonic eyes that had undergone filtering surgeries.

  8. In vivo ultrathin Descemet stripping automated endothelial keratoplasty with a low-energy and high-frequency femtosecond laser

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    Gustavo Victor

    2014-04-01

    Full Text Available This case report describes the production of an ultrathin endothelial donor corneal lamella using a femtosecond laser with low energy and a high frequency. In addition, we report its use in vivo in an eye with pseudophakic bullous keratopathy. The outcomes were observed 3 months after surgery in terms of the change in endothelial donor lamella and full cornea thickness (including pachymetric mapping, visual acuity, and endothelial cell count.

  9. Intraoperative Interface Fluid Dynamics and Clinical Outcomes for Intraoperative Optical Coherence Tomography-Assisted Descemet Stripping Automated Endothelial Keratoplasty From the PIONEER Study.

    Science.gov (United States)

    Hallahan, Katie M; Cost, Brian; Goshe, Jeff M; Dupps, William J; Srivastava, Sunil K; Ehlers, Justis P

    2017-01-01

    To correlate intraoperative interface fluid dynamics during Descemet stripping automated endothelial keratoplasty (DSAEK) using intraoperative optical coherence tomography (iOCT) in the Prospective Intraoperative and Perioperative Ophthalmic Imaging with Optical Coherence Tomography (PIONEER) study with postoperative outcomes. Prospective consecutive, interventional, comparative case series. One hundred seventy-eight eyes of 173 patients undergoing DSAEK from the Cole Eye Institute, Cleveland, Ohio. Eyes that underwent DSAEK between October 2011 and March 2014 from the PIONEER intraoperative and perioperative OCT study were included. An automated interface fluid segmentation algorithm evaluated intraoperative dynamics of interface fluid before and after surgical manipulations. iOCT images were also captured at multiple intraoperative time points for 2 different DSAEK techniques, 1 that used an active air infusion system and 1 that did not. Interface fluid metrics, graft nonadherence. iOCT measurements of interface fluid after final surgical manipulations and immediately before leaving the operating room identified that total fluid volume (P = .002), largest fluid volume pocket (P = .002), max fluid area (P = .006), mean fluid thickness (P = .03), and max fluid thickness (P = .01) significantly correlated with graft nonadherence rates within the first postoperative week. After placement and optimization of intraoperative lenticle adherence, iOCT revealed a significant difference between the area, volume, and thickness of maximum fluid pockets between the 2 surgical techniques, but both techniques resulted in significant reduction of interface fluid during the procedure. Larger residual interface fluid volume, area, and thickness at the end of surgery detected with iOCT are associated with early graft nonadherence and can be quantified with an automated algorithm. iOCT imaging can successfully capture technique-dependent differences in fluid dynamics during

  10. Trends in corneal transplant surgery in Ireland: indications and outcomes of corneal transplant surgery and intraocular lens opacification following Descemet's stripping automated endothelial keratoplasty.

    Science.gov (United States)

    Quigley, C; McElnea, E; Fahy, G

    2018-02-01

    To evaluate the indications for corneal transplantation, the procedures carried out, and the postoperative outcomes and to compare these with previous Irish corneal transplant studies. A retrospective review of the case notes of all patients who underwent corneal transplantation under the care of a single surgeon, from 2008 to 2015, was performed. The risk factors for postoperative complications including transplant failure were examined. During the period studied, 42 corneal transplant surgeries were carried out on 40 eyes of 38 patients, 24 of whom were male (63%), median age at surgery was 62 years (range 23-96 years). The most common indication for transplantation was pseudophakic corneal decompensation associated with Fuch's endothelial dystrophy (FED) (n = 13). Seventeen penetrating keratoplasties, 23 lamellar keratoplasties, and two amniotic membrane transplant procedures were carried out. Transplant failure resulting in corneal oedema or repeat corneal transplant surgery (n = 4, 10%), was associated with previous transplant failure in the eye; odds ratio (OR) = 1.58 (p = 0.05), and with comorbid FED, OR = 1.50 (p = 0.02). Intraocular lens opacification occurred in one lens following DSAEK, giving an incidence rate of 7%. Pseudophakic corneal decompensation is the commonest indication for corneal transplant surgery, with lamellar keratoplasty the most frequent approach in our cohort, reflecting developments observed in corneal transplant surgery elsewhere. Prior corneal transplant failure and Fuch's dystrophy remain important risk factors for failure. The risk of intraocular lens opacification and its potential effects on vision should be elaborated prior to endothelial keratoplasty.

  11. Visual outcome of penetrating keratoplasty, deep anterior lamellar keratoplasty and Descemet membrane endothelial keratoplasty.

    Science.gov (United States)

    Garrido, Clàudia; Cardona, Genís; Güell, Josep L; Pujol, Jaume

    2017-11-13

    A single-center, cross-sectional study was designed to assess and compare objective and subjective quality of vision of patients intervened with penetrating keratoplasty (PK), deep anterior lamellar keratoplasty (DALK) and Descemet membrane endothelial keratoplasty (DMEK). Forty-six patients previously intervened with PK (22 eyes), DALK (7 eyes) and DMEK (17 eyes) were recruited. Visual evaluation included spherical and cylindrical refraction, distance corrected visual acuity (DCVA), photopic contrast sensitivity (CS), optical quality, measured with the HD Analyzer (objective scattering index [OSI], MTF cut-off and Strehl ratio), and ocular and corneal aberrometry, measured with the KR-1W Wavefront Analyzer. Statistically significant between-group differences were found in age (p=0.006, DMEK patients were older) and time since surgery (pvisual function parameters under evaluation. Copyright © 2017 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

  12. Vision-related quality of life before and after keratoplasty for Fuchs' endothelial dystrophy.

    Science.gov (United States)

    Trousdale, Eleanor R; Hodge, David O; Baratz, Keith H; Maguire, Leo J; Bourne, William M; Patel, Sanjay V

    2014-11-01

    To assess vision-related quality of life in Fuchs' dystrophy and changes in vision-related quality of life after 3 types of keratoplasty (penetrating keratoplasty [PK], deep lamellar endothelial keratoplasty [DLEK], and Descemet stripping endothelial keratoplasty [DSEK]). Prospective, observational case series. Sixty-three subjects with Fuchs' endothelial dystrophy: 12 subjects (12 eyes) received PK, 11 subjects (11 eyes) received DLEK, and 40 subjects (40 eyes) received DSEK. Subjects were examined before keratoplasty and at regular intervals through 3 years after keratoplasty. At each examination, vision-related quality of life was assessed using the 25-item National Eye Institute Visual Functioning Questionnaire; best spectacle-corrected and uncorrected visual acuities were measured by using the electronic Early Treatment of Diabetic Retinopathy Study protocol; keratometric cylinder was measured by a manual keratometer. Disability glare was measured with a straylight meter. Vision-related quality of life composite score. Vision-related quality of life composite score for all eyes with Fuchs' dystrophy before keratoplasty was 72 ± 11 (n = 63) and did not differ between groups (P = 0.88). Vision-related quality of life improved by 6 months (PK, P = 0.008; DLEK, P = 0.03; DSEK, P Vision-related quality of life in patients with Fuchs' endothelial dystrophy is significantly impaired but improves after keratoplasty, irrespective of the technique. The improvement is faster after DSEK than after PK, and this might be explained in part by rapid improvement in uncorrected visual acuity after DSEK. This study affirms an advantage of endothelial keratoplasty over PK with respect to patient-reported outcomes. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  13. Endothelial cell density after deep anterior lamellar keratoplasty (Melles technique)

    NARCIS (Netherlands)

    van Dooren, Bart T. H.; Mulder, Paul G. H.; Nieuwendaal, Carla P.; Beekhuis, W. Houdijn; Melles, Gerrit R. J.

    2004-01-01

    To measure the recipient endothelial cell loss after the Melles technique for deep anterior lamellar keratoplasty. In 21 eyes of 21 patients, a deep anterior lamellar keratoplasty procedure was performed. Before surgery and at 6, 12, and 24 months after surgery, specular microscopy was performed to

  14. Simultaneous bilensectomy and endothelial keratoplasty for angle-supported phakic intraocular lens-induced corneal decompensation

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    Vikas Mittal

    2011-01-01

    Full Text Available A 40-year-old lady presented with severe endothelial cell loss in both eyes 14 years after angle-supported phakic intraocular lens (AS PIOL implantation. The left eye had severe corneal edema with bullous keratopathy. The right eye had markedly reduced endothelial cell count (655 cells/mm 2 although the cornea was clear. She underwent simultaneous bilensectomy (AS PIOL explantation and phacoemulsification and Descemet′s stripping and endothelial keratoplasty (DSEK in the left eye. Explanted AS PIOL was identified as ZSAL-4 (Morcher, Stuttgart, Germany model. Corneal edema cleared completely in 2 months with a best corrected visual acuity (-2.25 D sph of 20/60. No intervention was done in the right eye. The present case illustrates that AS PIOL-induced endothelial decompensation can be effectively managed by simultaneous bilensectomy and endothelial keratoplasty.

  15. Descemet's membrane endothelial keratoplasty surgery: update on the evidence and hurdles to acceptance.

    Science.gov (United States)

    Price, Marianne O; Price, Francis W

    2013-07-01

    Descemet's stripping endothelial keratoplasty (DSEK) is the most popular treatment for endothelial dysfunction, but Descemet's membrane endothelial keratoplasty (DMEK) now provides better vision with lower risk of immunologic rejection. Although DMEK is more challenging, advances in instrumentation and techniques are reducing the learning curve. In contrast to DSEK, which includes posterior donor stroma, DMEK consists merely of donor endothelium and Descemet's membrane, so DMEK does not create a stromal interface and induces significantly less posterior surface aberrations, resulting in better vision. Furthermore, multiple centers report remarkably low (<1%) cumulative probability of immunologic graft rejection episodes through 2 years after DMEK. Initially, the biggest challenges were tissue loss in preparation and ensuring attachment. Subsequent improvements have reduced complication rates to levels experienced with DSEK. DMEK/DSEK hybrids and 'thin' DSEK also can provide better vision than standard DSEK; randomized controlled comparisons with DMEK are needed. DMEK provides an anatomically exact replacement of dysfunctional host endothelium and has set new benchmarks for rejection risk and visual outcomes following endothelial replacement. DMEK is providing new insights into how different corneal layers contribute to immunogenicity and immune tolerance and into the key factors that limit vision after endothelial keratoplasty.

  16. Minimizing Graft Preparation Failure in Descemet Membrane Endothelial Keratoplasty.

    Science.gov (United States)

    Livny, Eitan; Groeneveld-van Beek, Esther A; Lie, Jessica T; Mangundap, Kristin M; Bruinsma, Marieke; Birbal, Rénuka S; van der Wees, Jacqueline; Melles, Gerrit R J

    2017-12-01

    To report the failure rate of 2 graft preparation techniques for Descemet membrane endothelial keratoplasty (DMEK) and to evaluate how to minimize graft preparation failure. Retrospective, nonrandomized study at an eye bank specialized in graft preparation for lamellar keratoplasty. For 1416 donor corneas, the DMEK graft preparation failure rate was evaluated for 2 different techniques, technique I: "Standardized traditional technique" (n = 341) and technique II: "Standardized no-touch technique" (n = 933), and for grafts that were converted from technique II to technique I during preparation (n = 142). The overall failure rate averaged 3.9% (55/1416): 7.0% (24/341) for technique I and 2.9% (31/1075) for technique II (P preparations which were converted from technique II to technique I failed in 13.4% (19/142), whereas for grafts that were entirely prepared by technique II, the failure rate was only 1.3% (12/933). The endothelial cell density decrease (before compared with after preparation) did not differ for both techniques (1.1% vs. 0.2%, P > 0.05). Various DMEK graft preparation techniques may provide failure rates of preparation" approach (technique II) may combine good graft quality (completely intact endothelial cell layer, ie, negligible preparation-induced endothelial cell density decrease) with low risk of dissection failure, leaving the possibility of conversion to "traditional preparation" (technique I) as a backup method.

  17. Endothelial keratoplasty using donor tissue not suitable for full-thickness penetrating keratoplasty.

    Science.gov (United States)

    Armour, Rebecca L; Ousley, Paula J; Wall, Jennifer; Hoar, Karen; Stoeger, Chris; Terry, Mark A

    2007-06-01

    To evaluate the use of corneal donor tissue deemed unsuitable for full-thickness penetrating keratoplasty (PK) for use in deep lamellar endothelial keratoplasty (DLEK) and to compare postoperative results to those of DLEK surgery using donor tissue that is suitable for PK. Small-incision DLEK surgery was performed using 39 donor corneas unsuitable for PK. Thirty-five donors had anterior scars or opacities, 3 donors had pterygia within the 8-mm zone, and 1 had prior LASIK. All donor preparation was completed by manual stromal dissection. The DLEK surgical and postoperative courses were reviewed. Preoperative and 6-month postoperative results of this study group were compared with a control group consisting of the first 55 consecutive small-incision DLEK patients receiving donor corneas that had no criteria excluding them from use in PK. Four eyes in the study group and 1 eye in the control group had the confounding variables of the presence of an anterior-chamber lens or surgical vitrectomy with macular disease in the recipient eye. There was no significant difference in preoperative measurements of best spectacle-corrected visual acuity (BSCVA; P = 0.372), donor endothelial cell density (ECD; P = 0.749), or corneal topography [surface regularity index (SRI), P = 0.485; or surface asymmetry index (SAI), P = 0.154] between the 2 groups. For the patients receiving corneas deemed unacceptable for PK, at 6 months after surgery, the vision (P = 0.002) and corneal topography measurements improved significantly from before surgery (SRI, P < 0.001; SAI, P < 0.001), and there was no significant change in refractive astigmatism (P = 0.240). There was a significant difference in the vision at 6 months postoperatively between the overall study group and the control group, with the mean vision of the study group at 20/56 and the control group at 20/43 (P = 0.015). If eyes with known cystoid macular edema (CME) and vitrectomy are removed from each group, there is no significant

  18. Descemet Membrane Endothelial Keratoplasty: Safety and Outcomes: A Report by the American Academy of Ophthalmology.

    Science.gov (United States)

    Deng, Sophie X; Lee, W Barry; Hammersmith, Kristin M; Kuo, Anthony N; Li, Jennifer Y; Shen, Joanne F; Weikert, Mitchell P; Shtein, Roni M

    2018-02-01

    To review the published literature on the safety and outcomes of Descemet membrane endothelial keratoplasty (DMEK) for the surgical treatment of corneal endothelial dysfunction. Literature searches were last conducted in the PubMed and the Cochrane Library databases most recently in May 2017. The searches, which were limited to English-language abstracts, yielded 1085 articles. The panel reviewed the abstracts, and 47 were determined to be relevant to this assessment. After DMEK surgery, the mean best-corrected visual acuity (BCVA) ranged from 20/21 to 20/31, with follow-up ranging from 5.7 to 68 months. At 6 months, 37.6% to 85% of eyes achieved BCVA of 20/25 or better and 17% to 67% achieved BCVA of 20/20 or better. Mean endothelial cell (EC) loss was 33% (range, 25%-47%) at 6 months. Overall change in spherical equivalent was +0.43 diopters (D; range, -1.17 to +1.2 D), with minimal induced astigmatism of +0.03 D (range, -0.03 to +1.11 D). The most common complication was partial graft detachment requiring air injection (mean, 28.8%; range, 0.2%-76%). Intraocular pressure elevation was the second most common complication (range, 0%-22%) after DMEK, followed by primary graft failure (mean, 1.7%; range, 0%-12.5%), secondary graft failure (mean, 2.2%; range, 0%-6.3%), and immune rejection (mean, 1.9%; range, 0%-5.9%). Overall graft survival rates after DMEK ranged from 92% to 100% at last follow-up. Best-corrected visual acuity after Descemet's stripping endothelial keratoplasty (DSEK) ranged from 20/34 to 20/66 at 9 months. The most common complications after DSEK were graft detachment (mean, 14%; range, 0%-82%), endothelial rejection (mean, 10%; range, 0%-45%), and primary graft failure (mean, 5%; range, 0%-29%). Mean EC loss after DSEK was 37% at 6 months. The evidence reviewed supports DMEK as a safe and effective treatment for endothelial failure. With respect to visual recovery time, visual outcomes, and rejection rates, DMEK seems to be superior to DSEK

  19. Outcomes of phacoemulsification after Descemet membrane endothelial keratoplasty.

    Science.gov (United States)

    Musa, Fayyaz U; Cabrerizo, Javier; Quilendrino, Ruth; Dapena, Isabel; Ham, Lisanne; Melles, Gerrit R J

    2013-06-01

    To evaluate the feasibility and outcomes of phacoemulsification after Descemet membrane endothelial keratoplasty (DMEK) for Fuchs endothelial dystrophy and bullous keratopathy. Tertiary referral center. Comparative case series. The case notes of all phakic DMEK patients who subsequently had cataract surgery were reviewed, and data from a prospectively recorded database were analyzed. This included demographic details, visual acuity, corneal pachymetry, endothelial cell density (ECD), refractive outcomes, and complications. From a series of 106 consecutive phakic DMEK eyes, 5 eyes (4.7%) required phacoemulsification a mean of 9.2 months ± 3.7 (SD) (range 4 to 14 months) after the initial DMEK. All phacoemulsification procedures were uneventful, and no dislocations and/or detachments of the Descemet graft were observed. At 6 to 12 months, all eyes reached a corrected distance visual acuity of 20/30 (0.6) or better and were within ±0.50 diopter of the target refraction. Endothelial cell density decreased from a mean of 1535 ± 195 cells/mm(2) before phacoemulsification to 1158 ± 250 cells/mm(2) 6 to 12 months after phacoemulsification. No significant changes in pachymetry values were observed, and all corneas remained clear throughout the study. Phacoemulsification after DMEK can be performed with minimal risk for graft detachment. The postoperative refractive outcomes were predictable, and visual acuity is likely to improve; there was an acceptable decrease in ECD. Dr. Melles is a consultant to D.O.R.C. International BV/Dutch Ophthalmic USA. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  20. Simple, inexpensive, and effective injector for descemet membrane endothelial keratoplasty.

    Science.gov (United States)

    Kim, Eun Chul; Bonfadini, Gustavo; Todd, Leisha; Zhu, Angela; Jun, Albert S

    2014-06-01

    We describe an inexpensive, simple, and effective endothelium-Descemet membrane (EDM) graft injector assembled from regular operating room supplies in Descemet membrane endothelial keratoplasty (DMEK). To assemble the injector, standard intravenous tubing was cut approximately 2 inches from the Luer lock end, leaving a steep bevel. The cut end of the tubing was firmly wedged bevel up and advanced into the back of an Alcon IOL B cartridge. The Luer lock end of the tubing was then attached to a 5- or 10-mL syringe filled with BSS Plus. The EDM graft was then placed into a Petri dish filled with BSS. After the graft was sucked into an injector with bevel-side up under the surgical microscope, the graft was then inserted into the anterior chamber with the injector through the main incision in the superotemporal quadrant. In seven eyes of seven patients with Fuchs endothelial corneal dystrophy treated with DMEK using our injector, clear attached grafts and improved visual acuity were achieved. This simple, inexpensive, and effective injector is a safe and viable device to facilitate this part of DMEK surgery.

  1. A comparative study on different Descemet membrane endothelial keratoplasty graft preparation techniques.

    Science.gov (United States)

    Parekh, Mohit; Borroni, Davide; Ruzza, Alessandro; Levis, Hannah J; Ferrari, Stefano; Ponzin, Diego; Romano, Vito

    2018-03-09

    To compare different Descemet membrane endothelial keratoplasty (DMEK) graft preparation methods. Stripping from the trabecular meshwork (M1) using epithelial spatula; stripping by scoring the peripheral endothelium (M2) using Sinskey hook; stripping by punch method (M3) using donor trephine; Submerged hydro-separation (M4); and pneumatic dissection method (M5) were evaluated. Preparation time, costs, endothelial cell loss (ECL) postpreparation, cell death and morphology were compared. Hoechst/Ethidium/Calcien AM (HEC) staining and Zonula Occludens-1 (ZO-1) expression were analysed. Statistical analysis was performed using one-way anova and; Tukey as post hoc test. A total of 35 corneas (seven per group) were used. Endothelial cell loss (ECL) represented as Mean (SD), in M1, M2, M3, M4 and M5 was 2.7 (5.0), 3.0 (7.4), 1.2 (7.4), 3.3 (7.3) and 4.1 (7.1)%, respectively not showing any difference between the groups (p = 0.96). A significantly higher cell death (p preparation time was significantly shorter in M4 and M5 and longest in M3 (p preparation technique. Minimum pleomorphic cells were observed in M1, M2 and M3, whereas moderate pleomorphism was seen in M4 and M5. Hoechst, Ethidium homodimer and Calcein AM (HEC) staining showed high Ethidium positivity (dead cells) in M4 and M5 with minimum positivity in M1, M2 and M3. Zonula Occludens-1 (ZO-1) was expressed in all the conditions except the denuded areas. Graft preparation using Sinskey hook (M2) and donor punch (M3) are reliable methods in terms of efficiency and quality with acceptable range of ECL. The preparation time and associated costs could be a limitation for M3. © 2018 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  2. Outcomes of Descemet membrane endothelial keratoplasty in phakic eyes.

    Science.gov (United States)

    Parker, Jack; Dirisamer, Martin; Naveiras, Miguel; Tse, Win Hou W; van Dijk, Korine; Frank, Laurence E; Ham, Lisanne; Melles, Gerrit R J

    2012-05-01

    To determine the clinical outcomes of isolated Descemet membrane transplantation (ie, Descemet membrane endothelial keratoplasty [DMEK]) in phakic eyes. Tertiary referral center. Cohort study. Phakic eyes from a larger group of consecutive eyes that had DMEK for Fuchs endothelial dystrophy were examined. The examination included corrected distance visual acuity (CDVA), subjective and objective refractions, endothelial cell density (ECD), and intraoperative and postoperative complications at 1, 3, and 6 months. The study enrolled 52 phakic eyes from a group of 260 DMEK eyes. Of the phakic eyes, 69% reached a CDVA equal to or better than 20/40 (≥0.5) within 1 week and 85% reached equal to or better than 20/25 (≥0.8) at 6 months. Compared with an age-matched control group of pseudophakic eyes, phakic eyes had a similar visual rehabilitation rate, final visual outcome, mean ECD at 6 months (1660 cells/mm(2) ± 470 [SD]), minor hyperopic shift (+0.74 diopter), and graft detachment rate (4%). Visual acuity equal to or better than 20/13 (≥1.5) was limited to phakic eyes, suggesting better optical quality with the crystalline lens in situ. Temporary mechanical angle-closure glaucoma due to air-bubble dislocation behind the iris was the main complication (11.5%). Two eyes (4%) required phacoemulsification after DMEK. In phakic eyes, DMEK may give excellent visual outcomes without an increased risk for complications. Visual acuities equal to or better than 20/13 (≥1.5) may indicate that the almost anatomic repair after DMEK is associated with near perfect optical quality of the transplanted cornea. Dr. Melles is a consultant to D.O.R.C. International/Dutch Ophthalmic USA. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  3. Postmortem ultrastructural analysis of a cornea transplanted with Descemet membrane endothelial keratoplasty.

    Science.gov (United States)

    Livny, Eitan; Parker, Jack S; van der Kaaij, Mariëlle; Haasdijk, Elize D; van der Wees, Jacqueline; Bruinsma, Marieke; Melles, Gerrit R J

    2014-08-01

    The aim of this study was to describe the ultrastructure of the host-donor interface in the eye of a recently deceased patient, who had undergone Descemet membrane endothelial keratoplasty. The eye was enucleated postmortem, and after standard decontamination, the corneoscleral button was excised, cut into 4 quadrants, and processed for light and transmission electron microscopy evaluation. Transmission electron microscopy revealed close attachment of the donor's Descemet membrane to the host's stroma and projection of stromal collagen fibers into the interfacial matrix, resembling a normal "virgin" corneal architecture. Ultrastructurally, an attached Descemet membrane endothelial keratoplasty graft closely resembles that of an unoperated, healthy eye with no appreciable adventitious or missing structures.

  4. Descemet Membrane Endothelial Keratoplasty Learning Curve for Graft Preparation in an Eye Bank Using 645 Donor Corneas.

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    Parekh, Mohit; Ruzza, Alessandro; Romano, Vito; Favaro, Elisa; Baruzzo, Mattia; Salvalaio, Gianni; Grassetto, Andrea; Ferrari, Stefano; Ponzin, Diego

    2018-03-01

    To investigate the learning curve of Descemet membrane endothelial keratoplasty (DMEK) graft preparation in an eye bank. Four operators prepared 645 DMEK grafts using the stripping technique between 2014 and 2017 at the Veneto Eye Bank Foundation, Italy. Endothelial cell loss (ECL) and tissue wastage were recorded retrospectively after DMEK preparation and correlated with the number of tissues prepared each year by each operator. On average, our operators performed 1 donor preparation a week over the course of this study. Only donors older than 60 years were used in this study, and approximately 10% of donors had diabetes. The Wilcoxon test for paired data and 1-way ANOVA were used for checking statistical significance with the Tukey test as post hoc analysis. P 0.05). There is a learning curve for DMEK graft preparation. ECL and tissue wastage can be reduced with practice and skills. However, each operator may be limited to his or her own learning capability.

  5. [Descemet's membrane endothelial keratoplasty (DMEK): Analysis of a variation in Descemet's endothelial graft preparation].

    Science.gov (United States)

    Benoist D'azy, C; Benoist D'azy, C; Gabison, E; Sapin, V; Bosc, C; Pereira, B; Chiambaretta, F

    2017-05-01

    Descemet's membrane endothelial keratoplasty (DMEK) can replace just the corneal endothelium and respect the natural corneal anatomy. Currently, the technique of endothelial graft preparation remains manual and non-standardized. To report anatomic and functional results after DMEK, and compare two techniques of graft preparation. Single-center retrospective study, including 64 eyes of 64 patients undergoing DMEK, from September 2014 to February 2016 at Clermont-Ferrand University Medical Center. The "classic" preparation was used in 44 patients (group 1) and the "variant" preparation was used in 20 patients (group 2). An analysis of functional parameters (visual acuity), anatomy (pachymetry, corneal edema, endothelial cell count) and keratometry (sphere, cylinder, mean keratometry) was performed during the first postoperative year. The mean follow-up was 10.0±2.5 months. The average preparation time was 12.3±8.1minutes, with 14.4±8.8 in group 1 versus 7.8±3.0 in group 2 (Ppreparation saved a considerable amount of time without decreasing graft survival or postoperative results. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  6. Descemet membrane endothelial keratoplasty (DMEK) early stage graft failure in eyes with preexisting glaucoma.

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    Treder, Maximilian; Alnawaiseh, Maged; Eter, Nicole

    2017-07-01

    To evaluate the effect of a preexisting glaucoma on the early postoperative outcome of a descemet membrane endothelial keratoplasty (DMEK). All patients who underwent DMEK surgery at the Department of Ophthalmology of the University of Muenster with a follow-up of at least 3 months (90d) were included in this study. The best corrected distance visual acuity (BCDVA), the intraocular pressure (IOD), the rate of re-keratoplasty and the rebubbling rate were inter alia recorded. The results of patients with (group 1) and without a preexisting glaucoma (group 2) were compared. 74 eyes of 59 patients with a mean follow-up of 152 ± 70 days were included. 65 eyes were in group 1 and 9 eyes in group 2. The BCDVA significantly improved in both groups after surgery (p < 0.03). The Re-keratoplasty rate (p = 0.172), the number of rebubblings per patient (p = 0.571) and the rebubbling rate (p = 0.939) were not significantly different in patients without glaucoma compared to patients with a preexisting glaucoma. In the early stage outcome of DMEK no significant impact of a preexisting glaucoma was found.

  7. Indications for and techniques of keratoplasty at Vietnam National Institute of Ophthalmology

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    Pham Ngoc Dong

    2016-03-01

    Full Text Available AIM: To report the indications for and techniques of corneal transplantation at Vietnam National Institute of Ophthalmology (VNIO over a period of 12y (2002-2013. METHODS: Records of patients who had undergone corneal transplantation at VNIO from January 1, 2002 to January 1, 2014 were reviewed to determine the indication for and type of corneal transplant performed. Patient age, gender, indication for corneal transplantation and surgical technique were recorded and analyzed. RESULTS: Corneal transplantation were underwent in 1390 eyes of 1278 patients with a mean age of 44.9±18.1y during the period under review. The most common indication was infectious corneal ulcer (n=670; 48.2%, followed by corneal scar (n=333, 24.0%, corneal dystrophy (n=138, 9.9% and failed graft (n=112, 8.1%. Nearly all procedures performed were penetrating keratoplasty (n=1300, 93.5%, with a few lamellar keratoplasty procedures performed: lamellar keratoplasty (n=52, 3.7%, Descemet’s stripping automated endothelial keratoplasty (n=27, 1.9% and deep anterior lamellar keratoplasty (n=11, 0.8%. CONCLUSION: While the most common indication for keratoplasty was infectious keratitis, nearly all indications for corneal transplantation were managed with penetrating keratoplasty. However, lamellar keratoplasty techniques, including deep anterior lamellar keratoplasty and Descemet’s stripping automated endothelial keratoplasty, are being performed with increasing frequency for isolated stromal and endothelial disorders, respectively.

  8. Validation of an endothelial roll preparation for Descemet Membrane Endothelial Keratoplasty by a cornea bank using "no touch" dissection technique.

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    Marty, Anne-Sophie; Burillon, Carole; Desanlis, Adeline; Damour, Odile; Kocaba, Viridiana; Auxenfans, Céline

    2016-06-01

    Descemet Membrane Endothelial Keratoplasty (DMEK) selectively replaces the damaged posterior part of the cornea. However, the DMEK technique relies on a manually-performed dissection that is time-consuming, requires training and presents a potential risk of endothelial graft damages leading to surgery postponement when performed by surgeons in the operative room. To validate precut corneal tissue preparation for DMEK provided by a cornea bank in order to supply a quality and security precut endothelial tissue. The protocol was a technology transfer from the Netherlands Institute for Innovative Ocular Surgery (NIIOS) to Lyon Cornea Bank, after formation in NIIOS to the DMEK "no touch" dissection technique. The technique has been validated in selected conditions (materials, microscope) and after a learning curve, cornea bank technicians prepared endothelial tissue for DMEK. Endothelial cells densities (ECD) were evaluated before and after preparation, after storage and transport to the surgery room. Microbiological and histological controls have been done. Twenty corneas were manually dissected; 18 without tears. Nineteen endothelial grafts formed a double roll. The ECD loss after cutting was 3.3 % (n = 19). After transportation 7 days later, we found an ECD loss of 25 % (n = 12). Three days after cutting and transportation, we found 2.1 % of ECD loss (n = 7). Histology found an endothelial cells monolayer lying on Descemet membrane. The mean thickness was 12 ± 2.2 µm (n = 4). No microbial contamination was found (n = 19). Endothelial roll stability has been validated at 3 days in our cornea bank. Cornea bank technicians trained can deliver to surgeons an ECD controlled, safety and ready to use endothelial tissue, for DMEK by "no touch" technique, allowing time saving, quality and security for surgeons.

  9. Correlation analysis of reject reaction and corneal endothelial cells after penetrating keratoplasty from donation after cardiac death

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    Qian Cao

    2017-01-01

    Full Text Available AIM: To study the relativity between reject reaction from donation after cardiac death(DCDand corneal endothelial cell source of corneal graft after penetrating keratoplasty.METHODS:Totally 28 cases of corneal graft rejection after penetrating keratoplasty with cardiac death donor cornea were analyzed using corneal endothelial microscope at less than 1mo, 2-3mo, 4-6mo, 7-12mo after operation.RESULTS:Coefficient variation of corneal endothelial cell of the 28 cases at less than 1mo,2-3mo, 4-6mo and 7-12mo were 38.23%, 49.56%, 57.18%, 65.04%. Corneal endothelial cell density were 2071.15±311.47, 1771.33±348.18, 1626.59±353.92, 1553.14±307.31. The coefficient variation of corneal endothelial cells was positively correlated with rejection(r=0.95, Pr=-0.93, PCONCLUSION: The corneal endothelial cell coefficient variation increased gradually and the corneal endothelial cell density decreased gradually after DCD corneal allograft rejection. Corneal endothelial cell coefficient variation and corneal endothelial cell density can be used as indicators of early detection of postoperative rejection.

  10. Standardization of the Descemet membrane endothelial keratoplasty technique: Outcomes of the first 450 consecutive cases.

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    Satué, M; Rodríguez-Calvo-de-Mora, M; Naveiras, M; Cabrerizo, J; Dapena, I; Melles, G R J

    2015-08-01

    To evaluate the clinical outcome of the first 450 consecutive cases after Descemet membrane endothelial keratoplasty (DMEK), as well as the effect of standardization of the technique. Comparison between 3 groups: Group I: (cases 1-125), as the extended learning curve; Group II: (cases 126-250), transition to technique standardization; Group III: (cases 251-450), surgery with standardized technique. Best corrected visual acuity, endothelial cell density, pachymetry and intra- and postoperative complications were evaluated before, and 1, 3 and 6 months after DMEK. At 6 months after surgery, 79% of eyes reached a best corrected visual acuity of≥0.8 and 43%≥1.0. Mean preoperative endothelial cell density was 2,530±220 cells/mm2 and 1,613±495 at 6 months after surgery. Mean pachymetry measured 668±92 μm and 526±46 μm pre- and (6 months) postoperatively, respectively. There were no significant differences in best corrected visual acuity, endothelial cell density and pachymetry between the 3 groups (P > .05). Graft detachment presented in 17.3% of the eyes. The detachment rate declined from 24% to 12%, and the rate of secondary surgeries from 9.6% to 3.5%, from group I to III respectively. Visual outcomes and endothelial cell density after DMEK are independent of the technique standardization. However, technique standardization may have contributed to a lower graft detachment rate and a relatively low number of secondary interventions required. As such, DMEK may become the first choice of treatment in corneal endothelial disease. Copyright © 2014 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  11. Air Versus Sulfur Hexafluoride Gas Tamponade in Descemet Membrane Endothelial Keratoplasty: A Fellow Eye Comparison.

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    von Marchtaler, Philipp V; Weller, Julia M; Kruse, Friedrich E; Tourtas, Theofilos

    2018-01-01

    To perform a fellow eye comparison of outcomes and complications when using air or sulfur hexafluoride (SF6) gas as a tamponade in Descemet membrane endothelial keratoplasty (DMEK). One hundred thirty-six eyes of 68 consecutive patients who underwent uneventful DMEK in both eyes for Fuchs endothelial corneal dystrophy were included in this retrospective study. Inclusion criteria were air tamponade (80% of the anterior chamber volume) in the first eye and 20% SF6 gas tamponade (80% of the anterior chamber volume) in the second eye; and same donor tissue culture condition in both eyes. All eyes received laser iridotomy on the day before DMEK. Main outcome measures included preoperative and postoperative best-corrected visual acuity, endothelial cell density, corneal volume, rebubbling rate, and rate of postoperative pupillary block caused by the air/gas bubble. Thirteen of 68 eyes (19.1%) with an air tamponade needed rebubbling compared with 4 of 68 eyes (5.9%) with an SF6 gas tamponade (P = 0.036). Postoperative pupillary block necessitating partial release of air/gas occurred in 1 eye (1.5%) with an air tamponade and 3 eyes (4.4%) with an SF6 gas tamponade (P = 0.301). There were no significant differences in preoperative and postoperative best-corrected visual acuity, endothelial cell density, and corneal volume within 3-month follow-up. Our results confirm the previously reported better graft adhesion when using an SF6 gas tamponade in DMEK without increased endothelial cell toxicity. The rate of pupillary block in eyes with an SF6 gas tamponade was comparable to that with an air tamponade. As a consequence, we recommend using SF6 gas as the tamponade in DMEK.

  12. Corneal endothelial rejection after penetrating keratoplasty treated with intravenous and topic corticosteroid: one year follow up

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    Ricardo Yuji Abe

    2013-02-01

    Full Text Available OBJECTIVE: To analyze the recovery of visual acuity (VA and graft survival after first episode of endothelial rejection in penetrating keratoplasty (PKP treated with intravenous (IV and topic corticosteroid. METHODS: Interventional, prospective, non-comparative case series study evolving 32 PKP patients in one year follow up, who presented first episode of corneal endothelial rejection. The patients were submitted to 500 mg IV injection of methylprednisolone in association with topical prednisolone. Main outcome measures included VA recovery and corneal edema regression. Second outcome included new rejections and graft failure. Multivariate analysis techniques were used to estimate rates of graft outcome events and the impact of risk factors. RESULTS: A total of 32 eyes from 32 patients (13 male and 19 female were included in the study. The mean VA (in number of letters before rejection was 48 (22 to 88 letters. Patients treated within 7 days or less of initial symptoms had better VA recovery, corneal edema regression and less graft failure (p<0.001. Patients with previous ocular surgery had worse VA recovery and more graft failure (p<0.047. CONCLUSION: The association between the other risk factors and the outcomes did not reach statistical significance in the multivariate model because of the small numbers of patients. Methylprednisolone in association with topical prednisolone is an alternative treatment for graft rejection. Our study showed that patients treated within 7 days of symptoms and no previous anterior segment surgery had better visual outcome and graft survival after treatment.

  13. Comparison of Sulfur Hexafluoride (SF6) and Air Tamponade in Noniridectomized Descemet Membrane Endothelial Keratoplasty.

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    Einan-Lifshitz, Adi; Sorkin, Nir; Boutin, Tanguy; Showail, Mahmood; Borovik, Armand; Jamshidi, Farzad; Chan, Clara C; Rootman, David S

    2018-03-01

    To compare the efficacy and safety of 20% sulfur hexafluoride gas (SF6) and air tamponade in patients who underwent noniridectomized Descemet membrane endothelial keratoplasty (DMEK). A retrospective chart review of patients who underwent DMEK with either air or SF6 tamponade: 41 eyes received air tamponade (group 1) and 41 received SF6 tamponade (group 2). Best spectacle-corrected visual acuity, endothelial cell density, and complications including graft detachment and elevated intraocular pressure were compared. The mean follow-up time was 8 ± 4 months in group 1 and 3 ± 2 months in group 2. Mean best spectacle-corrected visual acuity improved from 1.12 ± 0.88 to 0.64 ± 0.78 logarithm of the minimum angle of resolution (logMAR) in group 1 (P = 0.009) and from 1.00 ± 0.78 to 0.62 ± 0.53 logMAR in group 2 (P = 0.006). The graft detachment rate was 39% (16 eyes) in group 1 and 42% (17 eyes) in group 2 (P = 0.822). The rate of graft detachment larger than one third of the graft area was 17% in group 1 and 20% in group 2 (P = 0.775). Rebubbling was performed in 26.8% and 20% of eyes in group 1 and 2, respectively (P = 0.43). Average endothelial cell loss was 32% in group 1 and 33% in group 2 (P = 0.83). In the immediate postoperative period, elevated intraocular pressure was observed in 2 eyes (5%) in group 1 and in 4 eyes (10%) in group 2 (P = 0.4). There was 1 primary graft failure in each group. Use of air with it being readily available and short acting is a good method of Descemet membrane tamponade in noniridectomized DMEK.

  14. Rebubbling in Descemet Membrane Endothelial Keratoplasty: Influence of Pressure and Duration of the Intracameral Air Tamponade.

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    Pilger, Daniel; Wilkemeyer, Ina; Schroeter, Jan; Maier, Anna-Karina B; Torun, Necip

    2017-06-01

    To explore the impact of intracameral air tamponade pressure and duration on graft attachment and rebubbling rates. A prospective, interventional, nonrandomized study. setting: Department of Ophthalmology, Charité - Universitätsmedizin Berlin. One hundred seventeen patients who underwent Descemet membrane endothelial keratoplasty (DMEK). Intraocular pressure (IOP) at the end of the surgery, immediately after filling the anterior chamber with air, categorized into low (20 mm Hg), and the time until partial removal of the air. Rebubbling rates and endothelial cell density over a 3-month follow-up period analyzed by a multivariable Cox regression model and an analysis of covariance model. Thirty-two patients required a rebubbling (27% [95% CI 19%-35%]). Nine patients required more than 1 rebubbling (7% [95% CI 3%-12%]). Compared with normal IOP, lower (HR 8.98 [95% CI 1.07-75.41]) and higher IOP (HR 10.63 [95% CI 1.44-78.27]) increased the risk of requiring a rebubbling (P = .006). Independent of the IOP, an air tamponade duration beyond 2 hours reduced the risk of rebubbling (HR 0.36 [95% CI 0.18-0.71, P = .003]). One month after surgery, the mean endothelial cell loss was 13% (95% CI 2%-25%) and 23% (95% CI 17%-29%) in the group with air tamponade duration of below and above 2 hours, respectively (P = .126). At 3 months after surgery, it was 31% (95% CI 17%-42%) and 42% (95% CI 32%-52%) in the respective groups (P = .229). A postsurgical air tamponade of at least 2 hours with an IOP within the physiological range could help to reduce rebubbling rates. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Electrospun nanofibrous SF/P(LLA-CL membrane: a potential substratum for endothelial keratoplasty

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    Chen JZ

    2015-05-01

    Full Text Available Junzhao Chen,1,* Chenxi Yan,1,* Mengyu Zhu,1,* Qinke Yao,1 Chunyi Shao,1 Wenjuan Lu,1 Jing Wang,2 Xiumei Mo,2 Ping Gu,1 Yao Fu,1 Xianqun Fan1 1Department of Ophthalmology, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, 2Biomaterials and Tissue Engineering Laboratory, College of Chemistry and Chemical Engineering and Biotechnology, Donghua University, Shanghai, People’s Republic of China *These authors contributed equally to this work Background: Cornea transplant technology has progressed markedly in recent decades, allowing surgeons to replace diseased corneal endothelium by a thin lamellar structure. A thin, transparent, biocompatible, tissue-engineered substratum with corneal endothelial cells for endothelial keratoplasty is currently of interest. Electrospinning a nanofibrous structure can simulate the extracellular matrix and have beneficial effects for cell culture. Silk fibroin (SF has good biocompatibility but poor mechanical properties, while poly(L-lactic acid-co-Ɛ-caprolactone (P(LLA-CL has good mechanical properties but poor biocompatibility. Blending SF with P(LLA-CL can maintain the advantages of both these materials and overcome their disadvantages. Blended electrospun nanofibrous membranes may be suitable for regeneration of the corneal endothelium. The aim of this study was to produce a tissue-engineered construct suitable for endothelial keratoplasty.Methods: Five scaffolds containing different SF:P(LLA-CL blended ratios (100:0, 75:25, 50:50, 25:75, 0:100 were manufactured. A human corneal endothelial (B4G12 cell line was cultured on the membranes. Light transmission, speed of cell adherence, cell viability (live-dead test, cell proliferation (Ki-67, BrdU staining, and cell monolayer formation were detected on membranes with the different blended ratios, and expression of some functional genes was also detected by real-time polymerase chain reaction.Results: Different blended ratios of scaffolds

  16. Quantitative & qualitative analysis of endothelial cells of donor cornea before & after penetrating keratoplasty in different pathological conditions

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    Aruna K.R. Gupta

    2016-01-01

    Full Text Available Background & objectives: Endothelial cells of the donor cornea are known to be affected quantitatively and qualitatively in different pathological conditions after penetrating keratoplasty (PK and this has direct effect on the clarity of vision obtained after PK. This study was undertaken to analyze the qualitative and quantitative changes in donor endothelial cells before and after PK in different pathological conditions. Methods: A prospective investigational analysis of 100 consecutive donor corneas used for penetrating keratoplasty between June 2006 and June 2008, was conducted. The patients were evaluated on the first day, at the end of first week, first month, third and six months and one year. Results: A decrease was observed in endothelial cell count in all pathological conditions. After one year of follow up the loss was 33.1 per cent in corneal opacity, 45.9 per cent in acute infective keratitis (AIK, 58.5 per cent in regrafts, 28.5 per cent in pseudophakic bullous keratopathy (PBK, 37 per cent in descemetocele, 27 per cent in keratoconus and 35.5 per cent in aphakic bullous keratopathy (ABK cases. Interpretation & conclusions: The endothelial cell loss was highest in regraft cases which was significant (P<0.05, while the least endothelial cell loss was seen in keratoconus cases. The cell loss was associated with increase in coefficient of variation (CV, i.e. polymegathism and pleomorphism. Inspite of this polymegathism and pleomorphism, the clarity of the graft was maintained.

  17. A simple rescue maneuver for unfolding and centering a tightly rolled graft in Descemet membrane endothelial keratoplasty

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    Droutsas K

    2014-10-01

    Full Text Available Konstantinos Droutsas,1,2 Thomas Bertelmann,1 Frank M Schroeder,1 Dimitrios Papaconstantinou,2 Walter Sekundo1 1Department of Ophthalmology, Philipps University, Marburg, Germany; 2First Department of Ophthalmology, University of Athens, Medical School of Athens, Athens, Greece Abstract: A 74-year-old man underwent Descemet membrane endothelial keratoplasty (DMEK for endothelial decompensation due to Fuchs endothelial dystrophy. After descemetorhexis, the DMEK graft was inserted into the anterior chamber. However, unfolding of the graft was not possible as the graft was very tightly rolled together and the anterior chamber deep. After placing a 30G-cannula connected to an air-filled syringe inside the roll's lumen, a small air bubble was injected, which allowed the roll to open up, until it assumed a “taco” configuration around the bubble. Then, the graft was centered by pressing the posterior part of the roll against, and sweeping it over the iris. In the present case a “tight” DMEK roll was successfully unfolded by injection of a single air bubble into the roll’s lumen and centered by a “sweeping” the partialy unfolded graft over the iris. This technique allowed a controlled unfolding and centering of the DMEK graft with limited trauma to the donor endothelium and may be applied in cases where other less traumatic maneuvers are not successful. Keywords: Fuchs endothelial dystrophy, surgical technique, endothelial keratoplasty

  18. Incidence of irregular astigmatism eligible for contact lens fitting after Descemet membrane endothelial keratoplasty.

    Science.gov (United States)

    van Dijk, Korine; Parker, Jack; Liarakos, Vasilios S; Ham, Lisanne; Frank, Laurence E; Melles, Gerrit R J

    2013-07-01

    To evaluate the incidence and causes of anterior corneal surface irregularities after successful Descemet membrane endothelial keratoplasty (DMEK) and the efficacy of contact lens fitting in these cases. Tertiary referral center. Retrospective study of prospectively collected data. Eyes with a subnormal visual outcome or monocular diplopia after successful DMEK were fitted with a contact lens. These cases were evaluated with Pentacam rotating Scheimpflug camera imaging preoperatively and 6 months postoperatively, and outcomes were compared with those in a randomly selected DMEK control group. In a series of 262 surgeries, 23 eyes (21 patients) were fitted with contact lenses; the control group comprised 23 eyes. Indications for contact lens fitting included (1) obvious corneal surface irregularities due to preexisting corneal scarring, (2) surface irregularities associated with longstanding preoperative stromal edema, and (3) undetectable optical imperfections. The postoperative corrected distance visual acuity (CDVA) with spectacles improved after contact lens correction (PDutch Ophthalmic USA. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  19. Pre-Descemets endothelial keratoplasty: the PDEK clamp for successful PDEK.

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    Dua, H S; Said, D G

    2017-07-01

    PurposeTo design and produce a clamp that enables good handling of donor sclera-corneal disks, allows air to be injected in the corneal stroma and consistently provides pre-Descemets endothelial keratoplasty (PDEK) tissue by creation of a type-1 big bubble (BB) avoiding a type-2BB by shutting the fenestrations in the periphery of the pre-Descemets layer and preventing escape of air.Patients and methodsA clamp with spring loaded handles attached to two rings of 9 mm diameter and 1 mm width with a side port for insertion of a needle for air injection was designed and produced. The clamp was tested in 20 human donor sclera-corneal disks and refined over three prototypes. The final design was used for PDEK in 8 patients.ResultsThe clamp was able to prevent any escape of air or the formation of a type-2BB. By preventing air leak, it provided better control over the volume of air injected allowing for consistent formation of a type-1BB, which could be expanded to its full diameter by advancing the tip of the needle into the bubble cavity. Centration of tissue in the clamp was important. The clamp was used successfully to obtain PDEK tissue from 8 donor sclara-corneal disks for transplant in three eyes with pseudophakic bullous keratopathy and five eyes with pseudophakia and Fuchs' endothelial dystrophy.ConclusionThe PDEK clamp is a simple and useful instrument that will give surgeons the confidence of consistently obtaining PDEK tissue with ease and without the risk of separating the Descemets membrane in a type-2BB.

  20. Effectiveness and safety of endothelial keratoplasty for pseudophakic and aphakic bullous keratopathy: a systematic review of randomized controlled trials and cohort studies

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    Bruno Harfuch

    2016-06-01

    Full Text Available ABSTRACT Objective: For nearly a century, penetrating keratoplasty has been the surgical technique of choice in the management of corneal changes. However, in recent years, several lamellar keratoplasty techniques have been developed, modified or improved, especially techniques for replacing the posterior portion, for the correction of bullous keratopathy. The aim of this study was to evaluate the effectiveness and safety of endothelial keratoplasty versus penetrating keratoplasty for pseudophakic and aphakic bullous keratopathy. Methods: A systematic review of the literature was carried out, and the main electronic databases were searched. The date of the most recent search was from the inception of the electronic databases to December 11, 2015. Two authors independently selected relevant clinical trials, assessed their methodological quality and extracted data. Results: The electronic search yielded a total of 893 published papers from the electronic databases. Forty-four full-text articles were retrieved for further consideration. Of these 44 full-text articles, 33 were excluded because they were all case series studies; therefore, ten studies (with one further publication met the inclusion criteria: one randomized clinical trial with two publications; three controlled studies; and six cohort studies. The clinical and methodological diversity found in the included studies meant that it was not possible to combine studies in a metaanalysis. Conclusions: There is no robust evidence that endothelial keratoplasty is more effective and safe than penetrating keratoplasty for improving visual acuity and decreasing corneal rejection for pseudophakic and aphakic bullous keratopathy. There is a need for further randomized controlled trials.

  1. Infectious keratitis after keratoplasty.

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    Davila, Jose R; Mian, Shahzad I

    2016-07-01

    Infectious keratitis is an uncommon but serious complication after corneal transplantation that threatens the visual potential of corneal grafts. Several large retrospective studies from sites worldwide have documented the experiences of corneal surgeons with this sight-threatening complication. The present review synthesizes and compares incidence rates, risk factors, common microorganisms, treatments, and visual prognoses of patients with postkeratoplasty infectious keratitis. In 2012, endothelial keratoplasty replaced penetrating keratoplasty as the most commonly performed corneal transplantation procedure in the United States. Although reported rates of infectious keratitis after endothelial keratoplasty appear to be less than after penetrating keratoplasty, there are still too few publications documenting infectious keratitis after endothelial keratoplasty or anterior lamellar keratoplasty to adequately assess outcomes. Infectious keratitis continues to be a serious complication among all types of keratoplasty, threatening the viability of the grafted tissues and visual outcomes of patients. Reports from various sites worldwide indicate differences in incidence rates and common infecting microorganisms between high- and middle-income countries. Most reports agree that suture-related problems and factors contributing to a suboptimal ocular surface are the primary risk factors for developing infectious keratitis. In general, patients with infectious keratitis following keratoplasty have a poor visual prognosis because of the difficulty of successful treatment without residual scarring.

  2. Ceratoplastia endotelial lamelar profunda em distrofia de Fuchs: relato de caso Deep lamellar endothelial keratoplasty in Fuchs' dystrophy: case report

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    Fernando Trench de Oliveira Komatsu

    2004-08-01

    Full Text Available Descrever o caso de paciente portador de distrofia de Fuchs submetido a ceratoplastia endotelial lamelar profunda. O procedimento cirúrgico foi realizado no olho direito em um caso de distrofia de Fuchs com falência endotelial. Realizou-se incisão límbica superior, o estroma corneano foi delaminado e um disco lamelar de 8,5 mm com 0,150 mm de espessura, contendo estroma, membrana de Descemet e endotélio, foi transplantado sem sutura corneana. Foram avaliados: acuidade visual sem e com correção, biomicroscopia, topografia, paquimetria ultra-sônica e densidade endotelial. A paciente apresentava na avaliação pré-operatória acuidade visual com correção de 20/100 (+4,00 DE -3,25 DC x 60º, astigmatismo de 6,6 dioptrias (37,5 a 12º x 44,1 a 102º, espessura paquimétrica de 0,625 mm e contagem endotelial de 720 cel/mm². Após três meses da cirurgia, apresentava-se com acuidade visual com correção de 20/30 (-1,25 DE -0,50 DC x 45º, astigmatismo regular de 1,0 dioptria (37,2 a 75º x 38,2 a 165º, espessura paquimétrica de 0,503 mm e contagem endotelial de 2447 cel/mm². Observaram-se como complicações: corte inadvertido da íris, má coaptação de bordas, dobras do disco doador e nébula na interface. Os resultados preliminares sugerem que a ceratoplastia endotelial lamelar posterior é uma alternativa para o tratamento cirúrgico da distrofia de Fuchs com falência endotelial. Seguimento mais prolongado e maior número de casos são necessários para melhor entendimento e caracterização desta técnica e de suas repercussões.To report a case of deep lamellar endothelial keratoplasty (DLEK technique applied to a patient with Fuchs' dystrophy. The surgical procedure was performed on the right eye for a case of Fuchs' dystrophy with endothelial failure. Through a 9 mm self-sealing scleral tunnel incision, a stromal pocket was dissected at 0.35 mm depth. A 8.5 mm lamellar donor disc with 0.150 mm thickness, containing posterior

  3. [Precut technique for Descemet's membrane endothelial keratoplasty, preparation and storage in organ culture].

    Science.gov (United States)

    Bayyoud, T; Röck, D; Hofmann, J; Bartz-Schmidt, K-U; Yoeruek, E

    2012-06-01

    The preparation of the Descemet's membrane (DM) with the endothelial cell layer may be performed directly prior to surgery or as a precut tissue procedure. The purpose of the current study was the evaluation of the preparation technique and the tissue culture of 10 days regarding potential endothelial cell loss. Ten corneoscleral rims with an average age of 64.3 years were dissected to obtain 8.5 mm in diameter endothelial-DM complexes, which subsequently were organ cultured for 10 days. The endothelial cell density (ECD) was assessed during the cell culture period at days 1., 4., 7. and 10. In addition, time of preparation and transplant morphology were evaluated. The DM with the endothelial cell layer could successfully be dissected from all corneoscleral rims. The average preparation time was 8.3 min. The average ECD count was 2183 ± 77 cells/mm2 prior to, 2094 ± 110 cells/ mm2 at day 1, 2078 ± 134 cells/mm2 at day 4, 1977 ± 107 cells/mm2 at day 7 and 1898 ± 170 cells/mm2 at day 10 after preparation, respectively. Endothelial cell loss was 4.1 %, 4.8 %, 9.4 % and 13.1 % after preparation, respectively. None of the transplants exhibited large, centrally-located cell deficits. The isolated storage of DM with the endothelial layer, without any stromal remnants, showed gratifying results under storage conditions in organ culture with a moderate ECD decrease. Hence, the implementation of a precut DMEK is conceivable. © Georg Thieme Verlag KG Stuttgart · New York.

  4. Contact lens induced Pseudomonas keratitis following descemet stripping automated endothelial keratoplasty.

    Science.gov (United States)

    Dhiman, Rebika; Singh, Archita; Tandon, Radhika; Vanathi, M

    2015-10-01

    To report a case of bandage contact lens induced infectious keratitis caused by Pseudomonas aeruginosa following DSAEK. A 56-year-old female who underwent DSAEK at our institute for pseudophakic bullous keratopathy, developed contact lens induced keratitis in the fifth post operative week. Best corrected visual acuity (BCVA) reduced to perception of light in the left eye. Slit lamp examination revealed an epithelial ulcer measuring 4.7mm×6mm with surrounding infiltrates in the anterior stroma with hypopyon. The interface was clear. The corneoscleral rim culture of the donor tissue showed no growth on bacterial and fungal culture ruling out the possibility of donor-to-host transmission of infection. Microbiological evaluation identified the causative agent to be Pseudomonas aeruginosa. Based on culture and sensitivity report patient was started on hourly instillation of topical polymyxin B 20,000IU and fortified ceftazidime 5%. A response to treatment was noted and there was a complete resolution of keratitis with residual scarring. There have been case reports suggesting a host to donor transmission of infection which manifests during the postoperative period. To the best of our knowledge there are no reports of bandage contact lens associated Pseudomonas keratitis in a case that has undergone DSAEK. The prolonged use of bandage contact lens, lens contamination, stagnation of tear film behind the lens, compromised ocular surface and post operative use of topical steroids can contribute to infectious keratitis in DSAEK cases. Copyright © 2015 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  5. 360-Degree Iris Burns Following Conductive Keratoplasty.

    Science.gov (United States)

    Çakir, Hanefi; Genç, Selim; Güler, Emre

    2016-11-01

    The authors report a case with multiple iris burns after conductive keratoplasty to correct hyperopia. Case report. A 52-year-old woman with hyperopia had a previous conductive keratoplasty procedure and underwent a conductive keratoplasty re-treatment 6 months later. Postoperatively, she presented with 360-degree iris burns in both eyes that were correlated with the corneal conductive keratoplasty scars. In addition, specular microscopy revealed decreased endothelial cell density for both eyes. This is the first reported case of iris burns associated with conductive keratoplasty. [J Refract Surg. 2016;32(11):776-778.]. Copyright 2016, SLACK Incorporated.

  6. Detection of graft detachments immediately following Descemet membrane endothelial keratoplasty (DMEK) comparing time domain and spectral domain OCT.

    Science.gov (United States)

    Siebelmann, Sebastian; Gehlsen, Uta; Le Blanc, Carolin; Stanzel, Tisha Prabriputaloong; Cursiefen, Claus; Steven, Philipp

    2016-12-01

    Correct early graft attachment is believed to be crucial for final visual outcome after Descemet membrane endothelial keratoplasty (DMEK). Nonetheless, it is not yet known which imaging technique gives superior results for examining early postoperative graft adherence status. We compared imaging data taken with two different OCT devices to examine the development of graft adherence immediately after DMEK and to determine the superior device in terms of visualization of graft adherence. Ten consecutive patients (1 man/9 women) were examined three times postoperatively within the first 7 h after DMEK surgery using spectral domain OCT (SD-OCT) and time domain OCT (TD-OCT), as prospective case series and retrospective image data analyses. The parameters analyzed were localization and number, visibility and size of graft detachments. TD-OCT was able to detect a greater number of graft detachments after DMEK; however, SD-OCT provided better resolution of minor detachments. Graft detachments varied in position and degree at different time points immediately after surgery. All patients had some graft detachment within the first 7 h after DMEK surgery. TD-OCT enabled better overall analysis of graft detachments, even in the periphery, whereas SD-OCT allowed for the detection of even minor detachments, which suggests that a combination of the two techniques is optimal. Our results indicate that dynamic processes affecting the DMEK graft immediately after transplantation are responsible for changes in the attachment of donor tissue at an early postoperative stage. Modulation of early graft attachment may improve the final graft attachment.

  7. Femtosecond laser-assisted keratoplasty: full and partial-thickness cut wound strength and endothelial cell loss across a variety of wound patterns.

    Science.gov (United States)

    Kopani, Kamden R; Page, Michael A; Holiman, Jeff; Parodi, Armando; Iliakis, Bernie; Chamberlain, Winston

    2014-07-01

    To evaluate wound strength for patient safety during transport and endothelial viability when partial and complete femtosecond laser-assisted keratoplasty (FLAK) incisions are made in cadaveric corneas. 19 human corneoscleral rims were divided into six groups, mounted on an anterior chamber maintainer and cut with a femtosecond laser programmed to the following patterns: 'zigzag' (A), 'mushroom' (B) and 'top hat' (C) in both full (1) and partial (2) thicknesses. The pressure required to produce leakage from the corneal incision was then measured. Eight additional corneas were cut with the 'zigzag' pattern: four full and four partial thickness, prepared and transported per standard eye bank protocol, and analysed for endothelial cell loss with trypan blue staining and digital image analysis. Mean leakage pressure in mm Hg for group A1 was 110 (SD 94); group A2, 1180 (SD 468); group B1, 978 (SD 445); group B2, 987 (SD 576); group C1, 710 (SD 474); group C2, 1290 (SD 231). There was a significant difference in leakage pressure between groups A1 and A2 (p=0.05), groups A1 and B1 (p=0.05), and groups A1 and C1 (p=0.05). Mean percentage endothelial damage after full-thickness cuts was 8.40 (SD 2.34) and 5.30 (SD 1.33) in partial-thickness cuts (p=0.11). Partial thickness zigzag, top hat and mushroom-style partial FLAK incisions left an intact tissue wall with high resistance to rupture, whereas full-thickness cuts were more variable. Laser trephination and eye bank handling protocol for donor FLAK buttons leads to moderate peripheral endothelial cell loss in tissue with both complete and partial cuts.

  8. Air Pump-Assisted Graft Centration, Graft Edge Unfolding, and Graft Uncreasing in Young Donor Graft Pre-Descemet Endothelial Keratoplasty.

    Science.gov (United States)

    Jacob, Soosan; Narasimhan, Smita; Agarwal, Amar; Agarwal, Athiya; A I, Saijimol

    2017-08-01

    To assess an air pump-assisted technique for graft centration, graft edge unfolding, and graft uncreasing while performing pre-Descemet endothelial keratoplasty (PDEK) using young donor grafts. Continuous pressurized air infusion was used for graft centration, graft edge unfolding, and graft unwrinkling. Ten eyes of 10 patients underwent PDEK with donors aged below 40 years. In all eyes, the donor scrolled into tight scrolls. In all cases, the air pump-assisted technique was effective in positioning and centering the graft accurately and in straightening infolded graft edges and smoothing out graft creases and wrinkles. Endothelial cell loss was 38.6%. Postoperative best-corrected visual acuity at 6 months was 0.66 ± 0.25 in decimal equivalent. Continuous pressurized air infusion acted as a third hand providing a continuous pressure head that supported the graft and prevented graft dislocation as well as anterior chamber collapse during intraocular maneuvering. Adequate maneuvering space was available in all cases, and bleeding, if any, was tamponaded successfully in all cases. Although very young donor grafts may be used for PDEK, they are difficult to center and unroll completely before floating against host stroma. An air pump-assisted technique using continuous pressurized air infusion allows successful final graft positioning even with very young donor corneas. It thus makes surgery easier as several key steps are made easier to handle. It additionally helps in tamponading hemorrhage during peripheral iridectomy, increasing surgical space, preventing fluctuations in the anterior chamber depth, and promoting graft adherence.

  9. Hydrophilic intraocular lens opacification after posterior lamellar keratoplasty - a material analysis with special reference to optical quality assessment.

    Science.gov (United States)

    Giers, Bert C; Tandogan, Tamer; Auffarth, Gerd U; Choi, Chul Y; Auerbach, Florian N; Sel, Saadettin; Mayer, Christian; Khoramnia, Ramin

    2017-08-22

    Laboratory analysis and optical quality assessment of explanted hydrophilic intraocular lenses (IOLs) with clinically significant opacification after posterior lamellar keratoplasty (DMEK and DSAEK). Thirteen opacified IOLs after posterior lamellar keratoplasty, 8 after descemet stripping automated endothelial keratoplasty (DSAEK), 3 after descemet membrane endothelial keratoplasty (DMEK) and 2 after both DSAEK and DMEK were analysed in our laboratory. Analyses included optical bench assessment for optical quality, light microscopy, scanning electron microscopy (SEM) and energy dispersive X-Ray spectroscopy (EDS). In all IOLs the opacification was caused by a thin layer of calciumphosphate that had accumulated underneath the anterior optical surface of the IOLs in the area spared by the pupil/anterior capsulorhexis. The calcifications lead to a significant deterioration of the modulation transfer function across all spatial frequencies of the affected IOLs. The instillation of exogenous material such as air or gas into the anterior chamber increases the risk for opacification of hydrophilic IOLs irrespective of the manufacturer or the exact composition of the hydrophilic lens material. It is recommended to avoid the use of hydrophilic acrylic IOLs in patients with endothelial dystrophy that will likely require procedures involving the intracameral instillation of air or gas, such as DMEK or DS(A)EK.

  10. An 11-Year Review of Keratoplasty in a Tertiary Referral Center in Turkey: Changing Surgical Techniques for Similar Indications.

    Science.gov (United States)

    Bozkurt, Tahir Kansu; Acar, Banu; Kilavuzoglu, Ayşe Ebru; Akdemir, Mehmet Orçun; Hamilton, David Rex; Cosar Yurteri, Cemile Banu; Acar, Suphi

    2017-11-01

    Study aims to evaluate the indications and surgical techniques for corneal transplantation and to report changes in trends for preferred keratoplasty surgical techniques. Clinical records of 815 consecutive corneal transplantations between January 1, 2004 and December 31, 2014 in Haydarpasa Numune Training and Research Hospital Eye Clinic were analyzed and classified into seven broad groups according to indications. Main outcome measures were change of leading indications and trends for surgical techniques. Leading indications for keratoplasty were keratoconus (KCN) (27.7%), bullous keratopathy (BK) (23%), postinfectious corneal scars (13.5%), regrafts (13.1%), corneal dystrophies (12.1%), and noninfectious corneal scars (5.4%). Regrafts were the only indication with a significantly increasing trend (Ptechniques including deep anterior lamellar keratoplasty (DALK) and Descemet stripping automated endothelial keratoplasty (DSAEK), there was a significant increasing trend in number and percentage of both LK techniques (DALK; P=0.001 and P=0.007, and DSAEK; Ptechnique for KCN and BK indications, (P=0.007 and P=0.01, respectively). Although PK was the most common surgical technique over the 11-year period (54.7%), both anterior and posterior LK techniques showed an emerging trend as the procedures of choice when indicated. No major shift was observed in the clinical indications for corneal transplantation over the previous 11 years, except for regrafts. Lamellar keratoplasty techniques largely overtook the PK technique, but PK was still the overall preferred technique in the era when both LK techniques were used.

  11. [Indications for keratoplasty in District Railway Hospital in Katowice].

    Science.gov (United States)

    Wylegała, Edward; Dobrowolski, Dariusz; Tarnawska, Dorota; Wróblewska-Czajka, Ewa; Jurewicz, Antonina

    2005-01-01

    The retrospective analysis of indications for keratoplasty. The study of 517 keratoplasties between May 2000 and December 2004. The indications were: corneal oedema--24,5%, keratoconus--18,1%, corneal leucoma--15,0%, limbus insufficiency--10,2%, Fuchs endothelial dystrophy--9,0%, graft decompensation--8,1%, other acquired keratopaties--5,9%, corneal perforation--5,8%, anterior and stromal dystrophies--2,3%, Peters' syndrome--0,38%, choristoma--0,19%. Main indication for keratoplasty are corneal oedema and keratoconus.

  12. New techniques in lamellar keratoplasty.

    Science.gov (United States)

    Alio, Jorge L; Shah, Sunil; Barraquer, Carmen; Bilgihan, Kamil; Anwar, Mohammed; Melles, Gerrit R J

    2002-08-01

    In the past years, several lamellar keratoplasty surgical techniques have been developed, modified or improved in the past years, including microkeratome assisted anterior and posterior lamellar keratoplasty, anterior lamellar keratoplasty using air-dissection or visco-dissection, sutureless posterior lamellar keratoplasty, LASIK for postkeratoplasty astigmatism, and excimer laser assisted keratophakia for keratoconus or to manage complications after LASIK. These procedures may continue to gain interest as alternative procedures for a penetrating keratoplasty in the treatment of various corneal disorders.

  13. Femtosecond laser-assisted lamellar keratoplasty Transplante lamelar auxiliado pelo laser de fentosegundo

    Directory of Open Access Journals (Sweden)

    Hunson Kaz Soong

    2008-08-01

    Full Text Available Lamellar keratoplasty consists of transplanting partial-thickness donor cornea onto a complementary recipient bed. Manual lamellar dissection is technically very difficult, time-consuming, and imprecise. Also, the manually-dissected lamellar interface often has topographical irregularities that may optically degrade the best-corrected visual acuity. The femtosecond clinical laser (IntraLase FS LaserTM, Irvine, CA is a recent innovation that can be programmed to produce bladeless, precise lamellar cuts at any depth with accompanying trephination cuts for both anterior and posterior lamellar transplantion. Posterior laser cuts may be used to assist in deep lamellar endothelial keratoplasty or Descemet's stripping automated endothelial keratoplasty.A ceratoplastia lamelar consiste em transplante de espessura parcial da córnea doadora em um leito receptor complementar. A dissecção lamelar manual é técnica de difícil realização, imprecisa e que demanda tempo. Além disso, a interface lamelar freqüentemente apresenta irregularidade topográfica que pode comprometer a acuidade visual final. O laser clínico "femtosecond" (IntraLase FS LaserTM, Irvine, CA é uma recente inovação que pode ser utilizado para produzir cortes lamelares precisos em qualquer profundidade da córnea, acompanhados de cortes verticais tanto para transplantes lamelares anteriores como posteriores sem a utilização de lâminas. Os cortes posteriores podem ser utilizados para a realização de ceratoplastia endotelial lamelar profunda ou ceratoplastia endotelial com remoção da membrana de Descemet.

  14. Morphometric changes of corneal endothelial cells following intracameral air for micro perforation of the Descemet Membrane during big-bubble deep anterior lamellar keratoplasty

    Directory of Open Access Journals (Sweden)

    Ashbala Khattak

    2016-04-01

    Conclusion: The presence of air inside the anterior chamber for a short term may not cause further endothelial cell loss and can be safely performed to prevent postoperative Descemet Membrane detachment in case of micro perforations.

  15. Glaucoma Mini-Shunt Implantation After Keratoplasty.

    Science.gov (United States)

    Ledesma-Gil, Jasbeth; García-Rodríguez, María de Los Ángeles; Gurria, Lulu U; Graue-Hernández, Enrique O; Navas, Alejandro

    2017-04-01

    To report the outcomes of patients who underwent miniature glaucoma shunt implantation after secondary glaucoma due to keratoplasty. Prospective study of consecutive clinical cases who underwent mini-glaucoma shunt implantation following keratoplasty. In brief, a fornix-based conjunctival flap was performed, approximately 50% thickness scleral flap. Mitomycin C 0.025% placed under Tenon's capsule. A 25-G needle created entry for mini-shunt. Ex-PRESS model P-50 was inserted. Scleral flap and conjunctiva were closed with 10-0 Nylon. STATA 8.0 and SPSS software were used for statistical analysis. Seventeen eyes of 17 patients with a mean age of 39.70 years (SD=18.33, range: 18 to 76). A total of 64.70% were male and 35.30% female. Eleven cases after penetrating keratoplasty, 3 cases after triple procedure, 2 after deep anterior lamellar keratoplasty, and 1 following endothelial keratoplasty. Most of the indications for keratoplasty were keratoconus in 9 cases (52.94%), 4 due to endothelial failure (23.52%), 3 cases of herpetic keratitis (17.64%), and 1 case of post-LASIK ectasia (5.88%). Mean preoperative intraocular pressure was 35.94 mm Hg with maximal medical therapy (SD=9.65, range: 18 to 55). Decreasing intraocular pressure to 12.76 mm Hg postoperatively (SD=2.51, range 10 to 18) (P=0.001). Mean follow-up after mini-glaucoma shunt implantation was 23.76 months (SD=8.73, range: 10 to 35 mo). Preoperative mean uncorrected distance visual acuity (UDVA) was 1.31±0.63 (20/408 Snellen) and postoperative mean UDVA was 0.85±0.40 (20/141 Snellen) (P=0.001). Preoperative mean corrected distance visual acuity (CDVA) was 0.83±0.76 (20/135 Snellen) and postoperative mean CDVA was 0.56±0.44 (20/72 Snellen) (P=0.032). Ex-PRESS miniature glaucoma shunt could be an alternative treatment in postkeratoplasty glaucoma resistant to medical treatment. This technique may be helpful, in trying to avoid corneal damage produced by conventional glaucoma procedures.

  16. [Posterior lamellar keratoplasty with DSEK technique and use of the Tan EndoGlide - short-term results].

    Science.gov (United States)

    Kałuiny, Bartłomiej J; Piotrowiak, Ilona; Sołdańska, Beata; Grzybek, Katarzyna; Czajkowska, Monika; Galas, Małgorzata; Malukiewicz, Grazyna

    2013-01-01

    To present the differences in surgical technique of DSEK (Descemet's Stripping Endothelial Keratoplasty) with the use of Tan EndoGlide (Coronet, UK) and Busin Glide (Moria, FR). Short-term results will also be presented, DSEK was performed in 24 eyes, in 8 cases the surgery was combined with cataract phacoemulsification and lOL implantation. Surgery course and 6 months postoperative results of first 12 eyes performed with the use of Tan EndoGlide were compared with 12 consecutive eyes preformed with Busin Glide. Tan EndoGlide provided much more stable anterior chamber, donor tissue unfolding process was better controlled but the incision was wider incision. Surgically induced mean refractory cylinder 6. months after the surgery was 1.56 - 1.15 Dsph in Tan EndoGlide group and 1.18 +/- 1.10 Dsph in Busin Glide group (P 0.05). Mean CDVA was 0.65+/- 0.27 and 0.63 +/- 0.25, respectively (P>0,05). Statistically significant differences in intra- and post-operative complications between both groups were not found. The Tan EndoGlide used during posterior lamellar keratoplasty with DSEK technique is a good alternative to currently used methods. It provides better stabilization of the anterior chamber, however its use is linked with higher postoperative astigmatism in comparison with Busin Glide. The visual outcomes and endothelial cell loss 6 months after the surgery were similar in both groups.

  17. Maintenance of the anterior chamber during penetrating keratoplasty.

    Science.gov (United States)

    Kramer, S G; Stewart, H L

    1976-01-01

    A description of the author's (S.G.K.) technique for penetrating keratoplasty is provided. The salient features include corneal removal, storage, and corneal graft cutting procedures of Kaufman and his co-workers. In addition, a specially designed suturing contact lens is described which allows maintenance of the anterior chamber during penetrating keratoplasty. It is suggested that trauma to the all-important cornea endothelium can be minimized by application of this technique, because it significantly reduces the likelihood of endothelial trauma induced by mechanical contact of the endothelium with intraocular recipient structures during suturing.

  18. Noncontact laser photothermal keratoplasty. III: Histological study in animal eyes.

    Science.gov (United States)

    Ren, Q; Simon, G; Parel, J M

    1994-01-01

    Laser photothermal keratoplasty has been studied as a potential refractive procedure. The purpose of this study is to investigate the histological response to various laser treatments including geometrical patterns, radiant exposure levels, and pulse numbers. A noncontact laser photothermal keratoplasty system was used in this study. Epithelial and endothelial response to the laser photothermal keratoplasty annulus treatment pattern were studied on an owl monkey model with a 5-millimeter annulus ring pattern, 8 J/cm2, 25 consecutive pulses at 1 Hz. Epithelial and endothelial response to the laser photothermal keratoplasty spot pattern were then studied and compared on cat and rabbit models for safety monitoring. One pulse and five consecutive pulses of eight different radiant exposures (5.00 J/cm2 to 18.01 J/cm2) were applied on each cornea. A cadaver eye model was used to study the collagen shrinkage induced by the laser spot treatment following the same protocol as the cat and rabbit model. Finally, the biological healing response to the laser photothermal keratoplasty treatment with the optimal laser parameters obtained in our experiment was studied on the cat model. Five cats were treated by the laser photothermal keratoplasty procedure with eight spots on a 3-millimeter ring, 15.6 J/cm2, and 1 pulse. Epithelial and endothelial damage were observed after annulus treatment on an owl monkey's cornea at 8 J/cm2, 25 pulses, and after spot treatment on cat and rabbit corneas at 18.01 J/cm2, five pulses. No endothelial damage was observed on cat corneas for the single pulse treatment at 18.01 J/cm2. For the tissue shrinkage study, no laser photothermal keratoplasty lesion could be detected for a radiant exposure setting below 10.26 J/cm2. Histological cross-sections showed that the five-pulse treatment reached the endothelial layer at a radiant exposure of 13.4 J/cm2, while no single pulse treatment reached the endothelium for the radiant exposure range (5 J/cm2 to

  19. An "All-laser" Endothelial Transplant.

    Science.gov (United States)

    Rossi, Francesca; Canovetti, Annalisa; Malandrini, Alex; Lenzetti, Ivo; Pini, Roberto; Menabuoni, Luca

    2015-07-06

    The "all laser" assisted endothelial keratoplasty is a procedure that is performed with a femtosecond laser used to cut the donor tissue at an intended depth, and a near infrared diode laser to weld the corneal tissue. The proposed technique enables to reach the three main goals in endothelial keratoplasty: a precise control in the thickness of the donor tissue; its easy insertion in the recipient bed and a reduced risk of donor lenticule dislocation. The donor cornea thickness is measured in the surgery room with optical coherence tomography (OCT), in order to correctly design the donor tissue dimensions. A femtosecond laser is used to cut the donor cornea. The recipient eye is prepared by manual stripping of the descemetic membrane. The donor endothelium is inserted into a Busin-injector, the peripheral inner side is stained with a proper chromophore (a water solution of Indocyanine Green) and then it is pulled in the anterior chamber. The transplanted tissue is placed in the final and correct location and then diode laser welding is induced from outside the eyeball. The procedure has been performed on more than 15 patients evidencing an improvement in surgery performances, with a good recovery of visual acuity and a reduced donor lenticule dislocation event.

  20. An “All-laser” Endothelial Transplant

    Science.gov (United States)

    Rossi, Francesca; Canovetti, Annalisa; Malandrini, Alex; Lenzetti, Ivo; Pini, Roberto; Menabuoni, Luca

    2015-01-01

    The “all laser” assisted endothelial keratoplasty is a procedure that is performed with a femtosecond laser used to cut the donor tissue at an intended depth, and a near infrared diode laser to weld the corneal tissue. The proposed technique enables to reach the three main goals in endothelial keratoplasty: a precise control in the thickness of the donor tissue; its easy insertion in the recipient bed and a reduced risk of donor lenticule dislocation. The donor cornea thickness is measured in the surgery room with optical coherence tomography (OCT), in order to correctly design the donor tissue dimensions. A femtosecond laser is used to cut the donor cornea. The recipient eye is prepared by manual stripping of the descemetic membrane. The donor endothelium is inserted into a Busin-injector, the peripheral inner side is stained with a proper chromophore (a water solution of Indocyanine Green) and then it is pulled in the anterior chamber. The transplanted tissue is placed in the final and correct location and then diode laser welding is induced from outside the eyeball. The procedure has been performed on more than 15 patients evidencing an improvement in surgery performances, with a good recovery of visual acuity and a reduced donor lenticule dislocation event. PMID:26167711

  1. Recurrent Ectasia After Penetrating Keratoplasty

    Directory of Open Access Journals (Sweden)

    Ayşe Burcu

    2013-04-01

    Full Text Available Corneal ectasia or recurrent keratoconus after penetrating keratoplasty is rare, and few case reports exist in the literature concerning this condition. Computerized corneal topography is quite useful to identify and manage this disorder. Management consists of several methods ranging from spectacle and contact lens correction to repeated penetrating keratoplasty. Clinical and computerized topography findings of two patients with keratectasia following penetrating keratoplasty are presented in this article. Two healthy 45-year-old and 25-year-old male patients complained of decreased visual acuity following penetrating keratoplasty. Clinical and topographical data were consistent with recurrence of corneal ectasia. After repeated penetrating keratoplasty, best-corrected distance Snellen visual acuity of 0.7 was obtained in the 45-year-old patient. The other patient underwent collagen cross linking, received antiglaucomatous therapy, and his visual acuity reached 0.5. During the follow-up period, ectasia progression did not occur. (Turk J Ophthalmol 2013; 43: 124-8

  2. Fatty acids rather than hormones restore in vitro angiogenesis in human male and female endothelial cells cultured in charcoal-stripped serum

    OpenAIRE

    Vanetti, Claudia; Bifari, Francesco; Vicentini, Lucia M.; Cattaneo, Maria Grazia

    2017-01-01

    Charcoal-stripped serum (CSS) is a well-accepted method to model effects of sex hormones in cell cultures. We have recently shown that human endothelial cells (ECs) fail to growth and to undergo in vitro angiogenesis when cultured in CSS. However, the mechanism(s) underlying the CSS-induced impairment of in vitro EC properties are still unknown. In addition, whether there is any sexual dimorphism in the CSS-induced EC phenotype remains to be determined. Here, by independently studying human m...

  3. An ?All-laser? Endothelial Transplant

    OpenAIRE

    Rossi, Francesca; Canovetti, Annalisa; Malandrini, Alex; Lenzetti, Ivo; Pini, Roberto; Menabuoni, Luca

    2015-01-01

    The ?all laser? assisted endothelial keratoplasty is a procedure that is performed with a femtosecond laser used to cut the donor tissue at an intended depth, and a near infrared diode laser to weld the corneal tissue. The proposed technique enables to reach the three main goals in endothelial keratoplasty: a precise control in the thickness of the donor tissue; its easy insertion in the recipient bed and a reduced risk of donor lenticule dislocation. The donor cornea thickness is measured in...

  4. Hybrid Technique of Lamellar Keratoplasty (DMEK-S

    Directory of Open Access Journals (Sweden)

    Pavel Studeny

    2013-01-01

    Full Text Available Purpose: To evaluate the outcomes of the hybrid technique of posterior lamellar keratoplasty (DMEK-S. Materials and Methods: 71 eyes of 55 patients enrolled in a single-center study underwent posterior lamellar keratoplasty with a hybrid lamella DMEK-S implanted using a solution implantation technique, owing to endothelial dysfunction. The outcome measures studied were visual acuity and endothelial cell density. Results: The rate of endothelial cell loss caused by surgery was 43.8%. During followups, we observed the stabilization of postoperative findings, or at minimum a very low rate of corneal endothelial cell loss. The UCDVA and BCDVA dramatically improved postoperatively. The rebubbling rate in our group of patients was 61.9%. We replaced the lamella due to its failure or malfunction in 17 patients (23.9%. Conclusion: In summary, DMEK-S combines the advantages of DSEK/DSAEK and DMEK. The central zone of bare Descemet’s membrane and endothelium allows for very good visual outcomes, and the peripheral rim allows for better manipulation of the lamella during implantation. It is an effective method of treating the endothelial dysfunction of various etiologies, but the high complication rate needs to be addressed before widespread implementation of the technique in the future.

  5. Fatty acids rather than hormones restore in vitro angiogenesis in human male and female endothelial cells cultured in charcoal-stripped serum.

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    Claudia Vanetti

    Full Text Available Charcoal-stripped serum (CSS is a well-accepted method to model effects of sex hormones in cell cultures. We have recently shown that human endothelial cells (ECs fail to growth and to undergo in vitro angiogenesis when cultured in CSS. However, the mechanism(s underlying the CSS-induced impairment of in vitro EC properties are still unknown. In addition, whether there is any sexual dimorphism in the CSS-induced EC phenotype remains to be determined. Here, by independently studying human male and female ECs, we found that CSS inhibited both male and female EC growth and in vitro angiogenesis, with a more pronounced effect on male EC sprouting. Reconstitution of CSS with 17-β estradiol, dihydrotestosterone, or the lipophilic thyroid hormone did not restore EC functions in both sexes. On the contrary, supplementation with palmitic acid or the acetyl-CoA precursor acetate significantly rescued the CSS-induced inhibition of growth and sprouting in both male and female ECs. We can conclude that the loss of metabolic precursors (e.g., fatty acids rather than of hormones is involved in the impairment of in vitro proliferative and angiogenic properties of male and female ECs cultured with CSS.

  6. Fatty acids rather than hormones restore in vitro angiogenesis in human male and female endothelial cells cultured in charcoal-stripped serum.

    Science.gov (United States)

    Vanetti, Claudia; Bifari, Francesco; Vicentini, Lucia M; Cattaneo, Maria Grazia

    2017-01-01

    Charcoal-stripped serum (CSS) is a well-accepted method to model effects of sex hormones in cell cultures. We have recently shown that human endothelial cells (ECs) fail to growth and to undergo in vitro angiogenesis when cultured in CSS. However, the mechanism(s) underlying the CSS-induced impairment of in vitro EC properties are still unknown. In addition, whether there is any sexual dimorphism in the CSS-induced EC phenotype remains to be determined. Here, by independently studying human male and female ECs, we found that CSS inhibited both male and female EC growth and in vitro angiogenesis, with a more pronounced effect on male EC sprouting. Reconstitution of CSS with 17-β estradiol, dihydrotestosterone, or the lipophilic thyroid hormone did not restore EC functions in both sexes. On the contrary, supplementation with palmitic acid or the acetyl-CoA precursor acetate significantly rescued the CSS-induced inhibition of growth and sprouting in both male and female ECs. We can conclude that the loss of metabolic precursors (e.g., fatty acids) rather than of hormones is involved in the impairment of in vitro proliferative and angiogenic properties of male and female ECs cultured with CSS.

  7. Microbial Keratitis After Penetrating Keratoplasty.

    Science.gov (United States)

    Sun, Jen-Pin; Chen, Wei-Li; Huang, Jehn-Yu; Hou, Yu-Chih; Wang, I-Jong; Hu, Fung-Rong

    2017-06-01

    To report the incidence, microbiological profile, graft survival, and determining factors of microbial keratitis after penetrating keratoplasty (PK). Observational case series. The study involved 51 patients (52 eyes) who were treated at a single tertiary referral center during a 10-year period. Retrospective chart review included medical records of all patients diagnosed with microbial keratitis after penetrating keratoplasty at the National Taiwan University Hospital between January 2000 and December 2009. The main outcome measures were incidence of graft infection, microbial profile, and graft survival status. There were 871 PKs performed and 67 episodes in 52 eyes of culture-positive microbial keratitis during the study period. There were 32 infectious episodes (47.8%) in the first year post-PK and 35 episodes (52.2%) after the first year post-PK. Forty-four gram-positive bacterial isolates (57.9%), 17 gram-negative bacterial isolates (22.4%), and 15 fungal isolates (19.7%) were found. Twenty-three (34.3%) grafts remained clear after the infection episode with a mean follow-up of 1127 days (range, 25-3962 days). There was no difference in graft survival rate regarding the original indication of PK or offending pathogen. Suture-related infection was associated with decreased risk of graft failure (P = .02), while the factor associated with increased risk of graft failure was usage of antiglaucoma agents (P = .01). Infectious keratitis after penetrating keratoplasty leads to a high graft failure rate. Such complications can occur before or after the first year post-PK. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. An easy and inexpensive method for quantitative analysis of endothelial damage by using vital dye staining and Adobe Photoshop software.

    Science.gov (United States)

    Saad, Hisham A; Terry, Mark A; Shamie, Neda; Chen, Edwin S; Friend, Daniel F; Holiman, Jeffrey D; Stoeger, Christopher

    2008-08-01

    We developed a simple, practical, and inexpensive technique to analyze areas of endothelial cell loss and/or damage over the entire corneal area after vital dye staining by using a readily available, off-the-shelf, consumer software program, Adobe Photoshop. The purpose of this article is to convey a method of quantifying areas of cell loss and/or damage. Descemet-stripping automated endothelial keratoplasty corneal transplant surgery was performed by using 5 precut corneas on a human cadaver eye. Corneas were removed and stained with trypan blue and alizarin red S and subsequently photographed. Quantitative assessment of endothelial damage was performed by using Adobe Photoshop 7.0 software. The average difference for cell area damage for analyses performed by 1 observer twice was 1.41%. For analyses performed by 2 observers, the average difference was 1.71%. Three masked observers were 100% successful in matching the randomized stained corneas to their randomized processed Adobe images. Vital dye staining of corneal endothelial cells can be combined with Adobe Photoshop software to yield a quantitative assessment of areas of acute endothelial cell loss and/or damage. This described technique holds promise for a more consistent and accurate method to evaluate the surgical trauma to the endothelial cell layer in laboratory models. This method of quantitative analysis can probably be generalized to any area of research that involves areas that are differentiated by color or contrast.

  9. Analysis of the changes in keratoplasty indications and preferred techniques.

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    Stefan J Lang

    Full Text Available Recently, novel techniques introduced to the field of corneal surgery, e.g. Descemet membrane endothelial keratoplasty (DMEK and corneal crosslinking, extended the therapeutic options. Additionally contact lens fitting has developed new alternatives. We herein investigated, whether these techniques have affected volume and spectrum of indications of keratoplasties in both a center more specialized in treating Fuchs' dystrophy (center 1 and a second center that is more specialized in treating keratoconus (center 2.We retrospectively reviewed the waiting lists for indication, transplantation technique and the patients' travel distances to the hospital at both centers.We reviewed a total of 3778 procedures. Fuchs' dystrophy increased at center 1 from 17% (42 to 44% (150 and from 13% (27 to 23% (62 at center 2. In center 1, DMEK increased from zero percent in 2010 to 51% in 2013. In center 2, DMEK was not performed until 2013. The percentage of patients with keratoconus slightly decreased from 15% (36 in 2009 vs. 12% (40 in 2013 in center 1. The respective percentages in center 2 were 28% (57 and 19% (51. In both centers, the patients' travel distances increased.The results from center 1 suggest that DMEK might increase the total number of keratoplasties. The increase in travel distance suggests that this cannot be fully attributed to recruiting the less advanced patients from the hospital proximity. The increase is rather due to more referrals from other regions. The decrease of keratoconus patients in both centers is surprising and may be attributed to optimized contact lens fitting or even to the effect corneal crosslinking procedure.

  10. Deep anterior lamellar keratoplasty in the management of keratoconus

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    Rajesh Fogla

    2013-01-01

    Full Text Available Advanced cases of keratoconus often require surgical intervention to restore corneal anatomy and improve eyesight. Penetrating keratoplasty (PK although commonly performed has potential risk of immunological rejection and is now no longer automatically the first choice of surgery. DALK procedures have evolved, which allows surgical replacement of recipient′s corneal stroma, leaving behind healthy descemet membrane (DM and endothelium. This reduces the risk of allograft endothelial rejection and late graft failure. In recent times, DALK techniques have led to significant improvements in visual outcome and current results are comparable to PK. Big bubble technique of DALK has become the most popular among the various surgical techniques described. Manual near DM DALK also gives good outcome although the visual recovery is often delayed. Future integration of femtosecond laser technology along with diagnostic imaging technology is likely to further improve outcomes of DALK in keratoconus.

  11. Comparison of Descemet stripping under continuous air flow, manual air injection and balanced salt solution for DMEK: a pilot study.

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    Gabbay, I E; Bahar, I; Nahum, Y; Livny, E

    2017-08-01

    Descemet's membrane endothelial keratoplasty (DMEK) involves removal of the recipient's Descemet membrane (DM) prior to transplanting the donor's DM. When using balanced salt solution (BSS) or ophthalmic viscosurgical devices (OVDs), visualization of the host's DM during its stripping may be inadequate and may result in Descemet remnants and could lead to sub-optimal surgical results. Previous articles described excellent visualization when utilizing air injection but this requires repeated air injection into the anterior chamber (AC). We present a pilot study that compares different techniques under which DM stripping can be performed: with continuous automated air infusion, with manual air infusion, and with BSS. We retrospectively compared video footage of DM stripping with BSS, with continuous air and with manual injection of air into the AC to determine DM stripping duration and the number of times the surgeon had to insert and retrieve a surgical instrument from the AC. Thirty videos of 10 consecutive cases of the three DM stripping techniques were evaluated. DM stripping duration was 3.26 (±1.32), 3.92 (±1.2) and 12.9 (±3.98) minutes for BSS, continuous air flow, and manual air injection, respectively. Frequency of instrument retrieval (FIR) was 3.6 (±1.71), 1.5 (±0.71) and 15.1 (±3.28) for BSS, continuous air flow, and manual air injection, respectively. Continuous air flow and BSS were both statistically different than manual air injection into the AC (p air in the AC contributes to better visualization and an efficient surgery.

  12. Security research of cardiac death donation corneas used as penetrating keratoplasty grafts

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    Jing Xu

    2015-02-01

    Full Text Available AIM: To test the safety of using cardiac death donation(DCDcorneas for penetrating keratoplasty surgery graft. METHODS: In chronological order, suing DCD corneas penetrating keratoplasty, corneal endothelial cell density and best corrected visual acuity(BCVAwere tested 3~4mo after surgery. RESULTS: A total of 14 cases of DCD while 26 corneas were included in this study. Donors age ranged 0.5~61 years, averagely 38.3±15.6 years. Causes of death included that 9 cases of traumatic brain injury, 2 cases myocardial infarction, 2 cases brain stem hemorrhage, 1 case of respiratory and circulatory failure. All 26 patients underwent penetrating keratoplasty, no rejection occurred and all grafts were transparent 3~4mo after surgery. Three to four months after surgery, corneal endothelial cell density ranged 794~4 347/mm2, averaged 2 305±827/mm2, within which was only one case was lower than 1 000/mm2(3.8%, while 9 cases ranged from 1 000~2 000/mm2(34.6%, 16 cases were higher than 2 000/mm2(61.5%. The age of all the 26 receipts were from 20~80 years, mean 40.7±17.1 years. BCVA before surgery was light perception positive to 0.08, with an average 0.027±0.024. Three to four months after surgery, BCVA were 0.2~0.8, with an average 0.52±0.182 in contrast(t=3.96, PCONCLUSION: DCD donated corneas could be used for penetrating keratoplasty graft with high security.

  13. Disposable contact lenses in penetrating keratoplasty.

    Science.gov (United States)

    Arora, R; Gupta, S; Taneja, M; Raina, U K; Mehta, D K

    2000-07-01

    To evaluate the therapeutic efficacy of disposable contact lenses in management of complications after keratoplasty. Twenty-eight patients with various post keratoplasty complications were fit with disposable contact lenses (45% Vifilcon A and 55% water content). Indications for lens use included persistent epithelial defects, wound leak, graft edema, dry eye and protection of normal corneal epithelium. Success was obtained with the therapeutic use of disposable lenses in 20 of the 28 cases. The best results were seen in maintenance and restoration of healthy ocular surface and small wound leaks. Stromal graft edema with no epithelial involvement was the major area of therapeutic failure. Disposable contact lenses are an attractive low cost option in the management of complications after keratoplasty. They are particularly useful in maintaining a healthy ocular surface, providing symptomatic relief and avoiding resurgery in patients with small wound leaks.

  14. Modified suturing contact lens for penetrating keratoplasty.

    Science.gov (United States)

    Kramer, S G; Stewart, H L

    1978-11-01

    The authors have previously described a suturing contact lens that protects the corneal endothelium by aiding in the maintenance of the anterior chamber during penetrating keratoplasty. This report describes structural modifications of the suturing contact lens, which improve its stability and effectiveness. An additional configuration for use in corneal lacerations is presented.

  15. Elastic strips

    OpenAIRE

    Chubelaschwili, David; Pinkall, Ulrich

    2010-01-01

    Motivated by the problem of finding an explicit description of a developable narrow Moebius strip of minimal bending energy, which was first formulated by M. Sadowsky in 1930, we will develop the theory of elastic strips. Recently E.L. Starostin and G.H.M. van der Heijden found a numerical description for an elastic Moebius strip, but did not give an integrable solution. We derive two conservation laws, which describe the equilibrium equations of elastic strips. In applying these laws we find...

  16. Femtosecond laser enabled keratoplasty for advanced keratoconus

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    Yathish Shivanna

    2013-01-01

    Full Text Available Purpose : To assess the efficacy and advantages of femtosecond laser enabled keratoplasty (FLEK over conventional penetrating keratoplasty (PKP in advanced keratoconus. Materials and Methods: Detailed review of literature of published randomized controlled trials of operative techniques in PKP and FLEK. Results: Fifteen studies were identified, analyzed, and compared with our outcome. FLEK was found to have better outcome in view of better and earlier stabilization uncorrected visual acuity (UCVA, best corrected visual acuity (BCVA, and better refractive outcomes with low astigmatism as compared with conventional PKP. Wound healing also was noticed to be earlier, enabling early suture removal in FLEK. Conclusions: Studies relating to FLEK have shown better results than conventional PKP, however further studies are needed to assess the safety and intraoperative complications of the procedure.

  17. PENETRATING KERATOPLASTY IN MENTALLY RETARDED PATIENTS

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    Dušica Pahor

    2002-12-01

    Full Text Available Background. Penetrating keratoplasty (PK is rarely performed in mentally retarded patients, first of all because of numerous complications after surgery such as inflammation, self-inflicted injury, injury and because of difficult post-operative treatment. The aim of this study was to present the success of PK in this patients. In 16 years (from May 1984 to May 2000 201 PK were performed, but only three in mentally retarded patients.Methods. We present three cases of PK in mentally retarded patients. All the patients were men. They were 14, 16 and 27 year old. The indication for PK were in two cases acute keratoconus and in one case acute keratoglobus. The mean followup was 24.6 months. Trepanation was made with rotor threpin and donor material was sutured using single continuous 10-0 nylon suture.Results. In two cases keratoplasties stayed clear. Visual acuities were 0,4 and 0,5. In one patient with very aggressive behaviour graft failure developed with significant corneal vascularisation. Re-keratoplasty was not performed.Conclusions. Adequate post-operative care following PK in mentally retarded patients is the most important factor for the success of transplantation. The indication for the surgery must be made very carefully especially in self-aggressive patients in residential care.

  18. Outcome of therapeutic penetrating keratoplasty in a tertiary eye care center in Nepal

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    Bajracharya L

    2015-12-01

    Full Text Available Leena Bajracharya, Reeta Gurung Department of Cornea, Tilganga Institute of Ophthalmology, Kathmandu, Nepal Background: Corneal ulcer is an important cause of blindness in developing countries. Therapeutic keratoplasty for infective keratitis is a frequently performed surgery in these countries.Objective: To find out the outcome of therapeutic keratoplasty for infective keratitis.Methods: Records of 5 years were reviewed of patients who underwent therapeutic keratoplasty from 2006 to 2010. Data collected included demographic parameters, indications for surgery, microbiology of the ulcers, type of surgery performed, and donor tissue details. In the follow-up period, ocular status was evaluated in terms of eradication of disease, anatomic success, graft clarity, visual acuity, and development of glaucoma and cataract.Results: In all, 180 eyes of 180 patients were enrolled in the study; 59.4% of the patients were male. Average age was 44.4±16.7 years. Overall, 71% of infective keratitis was perforated. A total of 101 (56% eyes were positive for organisms of which 49 showed pure fungus and 49 showed pure bacteria. The commonest fungus and bacteria isolated were Aspergillus and Streptococcus, respectively. Average follow-up period was 29±23 months. Overall cure rate of infection was 88.8%, anatomical success rate was 89.5%, and graft clarity was 37.2%. Overall, 43.4% had secondary glaucoma. In the postoperative course, 65.8% of phakic eyes had developed cataract. In all, 38.6% of graft had endothelial failure and 24% of the graft failed due to late infective keratitis. Overall functional success with a visual acuity above 6/60 was 25.4%. Bacterial keratitis had a significantly higher cure rate, anatomical success, and graft clarity compared to fungal keratitis.Conclusion: Therapeutic keratoplasty is an important procedure to save the eye and preserve vision in severe infective keratitis. There is a high incidence of postoperative glaucoma

  19. Femtosecond laser-assisted sutureless anterior lamellar keratoplasty for superficial corneal opacities.

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    Jabbarvand, Mahmoud; Hashemian, Hesam; Khodaparast, Mehdi; Ghadimi, Hadi; Khalilipour, Elias

    2014-11-01

    To evaluate the visual and refractive outcomes, endothelial cell count (ECC), ocular surface changes, corneal aberrations, and biomechanical profile changes after femtosecond laser-assisted anterior lamellar keratoplasty surgery for superficial corneal scars. Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran. Prospective case series. Patients with superficial corneal scars had femtosecond laser-assisted anterior lamellar keratoplasty. Visual and refractive results, ECC, ocular surface changes, corneal aberrations, and biomechanical profiles were assessed preoperatively and for 1 year postoperatively. Nineteen eyes (19 patients) were evaluated. A significant decline occurred in refractive astigmatism and corneal astigmatism after 1 year. There was a nonsignificant reduction in corneal hysteresis and the corneal resistance factor from preoperatively to 1 year postoperatively. The corneal-compensated intraocular pressure (IOP) and Goldmann-correlated IOP increased during the follow-up; the increase was not significant. A statistically insignificant reduction in the root mean square for trefoil and spherical aberrations occurred between 1 month and 1 year postoperatively (P=.1 and P=.4, respectively). The decreases in primary coma and total higher-order aberrations approached significance (P=.08 and P=.07, respectively). There were no significant changes in the central corneal thickness, ECC, or ocular surface parameters. No intraoperative complications occurred. Femtosecond laser-assisted anterior lamellar keratoplasty was an efficient and safe procedure for improving the quality of vision in patients with anterior corneal pathology, and the results remained stable during the 1-year follow-up. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  20. Results of topography of the cornea following deep anterior lamellar keratoplasty

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    Ramin Salati

    2004-09-01

    Full Text Available There are no remarkable reports about the topographic characteristics of the cornea following deep anterior lamellar keratoplasty (DLKP. In this study we tried to characterize the corneal topographic patterns following DLKP, and determine the correlations between these patterns with other factors. In this study optical DLPP with Melles technique was performed on 40 keratoconus eyes. Each patient was examined in four separate sessions once preoperatively, and three sessions at 3, 6, and 12 months postoperatively. The corneal topographic pattern of each exam was identified, and its correlations with other factors such as suturing technique were evaluated. The decreases in mean keratometry and mean corneal astigmatism and the conversion of irregular topographic patterns to regular patterns were significant following the operation. There were not any cases of immunologic endothelial rejection. We conclude that DLKP is a safe and predictable surgical treatment in keratoconus eyes.

  1. Penetrating keratoplasty versus lamellar keratoplasty for mustard gas-induced keratitis.

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    Feizi, Sepehr; Javadi, Mohammad A; Jafarinasab, Mohammad R; Karimian, Farid

    2013-04-01

    To compare the outcomes of penetrating keratoplasty (PK) and lamellar keratoplasty (LK) in patients with mustard gas keratitis. A total of 78 eyes of 55 patients with mustard gas keratitis were included. Of these eyes, 27 (34.6%) underwent PK and 51 (63.4%) received LK. Keratolimbal allografts were performed in 11 and 30 eyes of the PK and LK groups, respectively. The study groups were compared in terms of best spectacle-corrected visual acuity, refractive error, and keratometry readings. The Kaplan-Meier survival curve and log-rank test were used to evaluate and compare the cumulative incidence of rejection-free graft survival and graft survival in PK and LK. At the time of keratoplasty, the mean patient ages were 40.3 ± 4.5 years and 43.4 ± 8.3 years in the PK and LK groups, respectively (P = 0.08). The patients were followed-up for 53.2 ± 27.5 and 40.4 ± 29.6 months, respectively (P = 0.09). At the last follow-up, the 2 study groups were comparable with respect to best spectacle-corrected visual acuity (P = 0.87), refraction (P = 0.08), and keratometric astigmatism (P = 0.27). At the 33-month follow-up examination, the rejection-free graft survival rates were 33.6% in the PK group and 90% in the LK group, with mean durations of 34.6 and 84.8 months, respectively (P mustard gas victims. However, PK should always be performed in certain conditions.

  2. Contact Lens Visual Rehabilitation in Keratoconus and Corneal Keratoplasty

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    Yelda Ozkurt

    2012-01-01

    Full Text Available Keratoconus is the most common corneal distrophy. It’s a noninflammatory progressive thinning process that leads to conical ectasia of the cornea, causing high myopia and astigmatism. Many treatment choices include spectacle correction and contact lens wear, collagen cross linking, intracorneal ring segments implantation and finally keratoplasty. Contact lenses are commonly used to reduce astigmatism and increase vision. There are various types of lenses are available. We reviewed soft contact lenses, rigid gas permeable contact lenses, piggyback contact lenses, hybrid contact lenses and scleral-semiscleral contact lenses in keratoconus management. The surgical option is keratoplasty, but even after sutur removal, high astigmatism may stil exists. Therefore, contact lens is an adequate treatment option to correct astigmatism after keratoplasty.

  3. Clinical research on 150 cases of penetrating keratoplasty

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    Shuang Ni

    2014-05-01

    Full Text Available AIM:To investigate the main reasons,effects and complications of penetrating keratoplasty. METHOTS: Retrospective analysis on 150 cases(150 eyesof penetrating keratoplasty was done from Jan.2011 to June 2013. RESULTS: Reasons: coneal lecuma 99 eyes(66%; corneal degeneration 18 eyes(12%; corneal ulcers 15 eyes(10%; corneal endothelium decompensation 10 eyes(6.7%; keratoconus 8 eyes(5.3%. Effects: Grafts were transparent in 110 eyes(73.3%. There are 42 eyes(28%less than or equal to 0.05 in visual acuity,60 eyes(40%better than 0.05 and less than or equal to 0.3 and 48 eyes(32%better than 0.3. Complication: The main complication was immune rejection(28 eyes, 18.7%.CONCLUSION: Penetrating keratoplasty is an important and effective means for keratitis disease.

  4. Indications and outcome of repeat penetrating keratoplasty in India

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    Titiyal Jeewan S

    2005-11-01

    Full Text Available Abstract Background Repeat penetrating keratoplasty is quite often required as there is high chance of failure of the primary graft particularly in the developing world. We planned a study to analyze the indications and outcome of repeat penetrating keratoplasty in a tertiary care centre in India. Methods A retrospective analysis of all the patients who underwent repeat penetrating keratoplasty, between January 1999 and December 2001 was performed. The parameters evaluated were indication for the primary penetrating keratoplasty, causes of failure of the previous graft, and final visual outcome and clarity of the repeat corneal grafts. Results Of fifty-three eyes of 50 patients with repeat penetrating keratoplasty (three patients underwent bilateral corneal regrafts, 37 eyes had undergone one regraft each, 14 eyes two regrafts and two eyes had three regrafts. The follow-up of the patients ranged from one to three years. The most common primary etiologic diagnosis was vascularized corneal scars (66%, of which the scars related to infection were most common (68.5%. Twenty-eight regrafts (52.8% remained clear at a mean follow-up of 1.54 ± 0.68 years, of which 25 were single regrafts (89.3%. The commonest cause of failure of regraft was infection to the corneal graft (recurrence of herpetic infection in 9 eyes and perforated graft ulcers in 3 eyes. Three (18.6% of the 16 eyes with multiple corneal regrafts achieved a BCVA of 6/60. Overall, only five eyes (all with single regraft achieved a BCVA of 6/18 or better at the end of follow-up. Conclusion Graft infection is the leading cause of failure of repeat keratoplasty in this part of the world. Prognosis for visual recovery and graft survival is worse in eyes undergoing multiple regrafts.

  5. Laser in-situ keratomileusis after penetrating keratoplasty.

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    Vajpayee, Rasik B; Sharma, Namrata; Sinha, Rajesh; Bhartiya, Prashant; Titiyal, Jeewan S; Tandon, Radhika

    2003-01-01

    Laser in situ keratomileusis (LASIK) after penetrating keratoplasty has been used more commonly for the correction of myopia or myopic astigmatism and less so for hypermetropia or hyperopic astigmatism. The primary goal after LASIK in such cases is resolution of sufficient myopia and astigmatism to allow spectacle correction of the residual refractive error and decrease anisometropia. All sutures should be removed prior to LASIK and the interval between penetrating keratoplasty and LASIK should be a minimum of 1 year. Preoperative evaluation includes refraction, slit-lamp biomicroscopy, corneal topography, and specular microscopy. The technique of LASIK surgery after penetrating keratoplasty is similar to the standard procedure. However, many variations have been described. These include maneuvers during surgery such as augmentation with arcuate cuts on the stromal bed and topographically guided LASIK. Other variations are relaxing incisions followed by LASIK surgery and sequential treatment by LASIK, that is, raising of the flap as a first stage procedure followed by ablation if required, 4 to 6 weeks later after relifting the flap in the second stage. Improvement in both uncorrected visual acuity and spectacle-corrected visual acuity, as well as a decrease in spherical equivalent, cylinder, and anisometropia, has been reported in various studies. All grafts were clear and no occurrence of wound dehiscence has been reported. Intraoperative complications include hemorrhage, microkeratome failure, flap buttonhole, dislocation, and perforation. Postoperative complications include undercorrection, decentered ablation, and regression. Re-enhancements after LASIK following keratoplasty are possible with acceptable visual outcome.

  6. Ceratoplastia penetrante e glaucoma Penetrating keratoplasty and glaucoma

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    Márcio Eulálio Barreto Soares

    2007-08-01

    Full Text Available O objetivo deste artigo é discutir os conhecimentos atuais sobre a abordagem clínica e terapêutica da ceratoplastia penetrante e do glaucoma a ela associado.The aim of this article is to make a review about glaucoma associated with penetrating keratoplasty, describing since its incidence and risk factors until the different options for treatment.

  7. Research advances on tissue-engineered corneal endothelial cells transplantation

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    Si-Jie Zhao

    2015-02-01

    Full Text Available Due to the serious shortage of donor cornea materials and the donor limit, clinical popularization of penetrating keratoplasty is severely restricted. It is a hot spot of current research that applying tissue engineering in vitro to culture corneal endothelial cells(CECwith high density, regular hexagonal shape and healthy endothelial function. In this article, we reviewed the latest progress in the study of source of CEC seeder cells, selection of cultivating carries, type of CEC transplantation and immune mechanism that summarized the current research problems and made a prospect to the future.

  8. MMSC-LIKE LIMBAL CELLS COTRANSPLANTATION PROMOTES LOCAL IMMUNOCORRECTION AND CORNEAL GRAFT TRANSPARENT RETENTION IN HIGH RISK KERATOPLASTY

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    S. A. Borzenok

    2014-01-01

    Full Text Available Aim was to evaluate clinical results of donor corneal graft survival in high-risk recipients in co-transplantation of preserved allogenic limbal grafts. Materials and methods. Two types of penetrative keratoplasties were carried out in patients with corneal graft opacities and high risk of rejection (n = 69. Co-transplantation of donor cornea and allogenic MMSC-like limbal cells in the form of limbal transplants was carried out in the 1st group (n = 36; in the 2nd group (n = 33 only the cornea was transplanted. Results. Observation of the patients during one year after surgery showed that the rate of transparent cornea engraftment increased in the 1st group (86,1 against 69,7% in the 2nd group. The density of endothelial cells was also higher in the 1st group (85,9 against 76,2% in the 2nd group. At the same time, progressive decreasing of pro-inflammatory cytokines (IL-6, IFNγ, TNFα and increasing of anti-inflammatory cytokines (IL-10, IL-1RA, TGFβ along with higher level of HLA-G5 were revealed in the recipients’ tear fluid in the 1st group in comparison to the 2nd group. Conclusion. Simultaneous transplantation of preserved limbal grafts with corneal graft in high-risk keratoplasty favors the transparent cornea engraftment, obviously, this is due to immunoregulatory activity of the MMSC-like limbal cells. 

  9. Varicose vein stripping

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    ... stripping; Venous reflux - vein stripping; Venous ulcer - veins Patient Instructions Surgical wound care - open Varicose veins - what to ask your doctor Images Circulatory system References American Family Physician. Management of varicose veins. www.aafp.org/afp/2008/ ...

  10. Rapid visual recovery after penetrating keratoplasty for keratoconus.

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    Sutton, Gerard; Hodge, Chris; McGhee, Charles N J

    2008-11-01

    To ascertain the level and speed of visual recovery after penetrating keratoplasty for keratoconus. A retrospective review was performed of 100 consecutive cases of penetrating keratoplasty for keratoconus, performed between 1999 and 2005. Review assessed visual function and the speed at which patients achieved a functional best corrected visual acuity (BCVA) of > or = 6/12 either with glasses or phoropter. Analysis of visual, refractive and keratometric results were made on 76 eyes that had reached 6 months after suture removal. Intraoperative and postoperative complications including graft rejections were recorded. Post keratoplasty, 43.4%, 78.9% and 96.1% of patients achieved a BCVA of 6/12 or better by 1, 3 and 6 months, respectively. The mean time to achieve a BCVA of 6/12 was 9.6 weeks. Only 5.3% of patients required a rigid gas permeable contact lens. Overall 42.4% of patients had unaided visual acuity of 6/12 or better at 12 months. The mean refractive cylinder and standard deviation was 2.78 +/- 1.6 D, and the mean spherical equivalent was -1.12 +/- 2.9 D. There were no significant intraoperative complications, and although 3.9% of eyes had at least one graft rejection episode there were no graft failures. Penetrating keratoplasty is an effective method for treating advanced keratoconus. By 3 months almost all patients are able to achieve a BCVA of 6/12 or better with progressive improvement over time. This technique allows almost half of patients to achieve an unaided vision of 6/12 or better with sutures in situ.

  11. Quality of Vision after Deep Anterior Lamellar Keratoplasty (Fluid Dissection Compared to Penetrating Keratoplasty for the Treatment of Keratoconus

    Directory of Open Access Journals (Sweden)

    Islam Mahmoud Hamdi

    2017-01-01

    Full Text Available Purpose. To compare the visual quality of patients with keratoconus who underwent penetrating keratoplasty (PKP or deep anterior lamellar keratoplasty (DALK with fluid dissection. Design. Cross-sectional, observational study. Methods. Twelve eyes that underwent PKP (PKP group were compared to 24 eyes that underwent DALK (DALK group after complete removal of sutures and stability of refraction. Visual, refractive, corneal topographic, corneal aberrometry, and ocular aberrometry parameters were compared for both groups. The χ2 and Mann–Whitney U tests were used for comparisons as appropriate. P0.05, all comparisons. All aberrations, point spread functions (PSF, and the modulation transfer function (MTF were not statistically different between groups (P>0.05. Conclusion. For our small study, the postoperative PKP and DALK with fluid dissection patient groups had vision/optical quality parameters that were not statistically different. This may indicate that DALK with fluid dissection can replace PKP for keratoconus without compromising vision quality.

  12. Lateral flow strip assay

    Science.gov (United States)

    Miles, Robin R [Danville, CA; Benett, William J [Livermore, CA; Coleman, Matthew A [Oakland, CA; Pearson, Francesca S [Livermore, CA; Nasarabadi, Shanavaz L [Livermore, CA

    2011-03-08

    A lateral flow strip assay apparatus comprising a housing; a lateral flow strip in the housing, the lateral flow strip having a receiving portion; a sample collection unit; and a reagent reservoir. Saliva and/or buccal cells are collected from an individual using the sample collection unit. The sample collection unit is immersed in the reagent reservoir. The tip of the lateral flow strip is immersed in the reservoir and the reagent/sample mixture wicks up into the lateral flow strip to perform the assay.

  13. Deep Anterior Lamellar Keratoplasty Using the Big-Bubble Technique in Keratoconus

    Science.gov (United States)

    Javadi, Mohammad-Ali; Feizi, Sepehr; Jamali, Hossein; Mirbabaee, Firooz

    2009-01-01

    Purpose To evaluate the visual outcomes and complications of deep anterior lamellar keratoplasty (DALK) using the big-bubble technique in patients with keratoconus. Methods In this case series, 104 eyes of 99 patients with moderate to advanced keratoconus underwent DALK. All subjects were contact lens intolerant or had unacceptable spectacle-corrected visual acuity. DALK was performed using the big-bubble technique. Full thickness donor corneas devoid of Descemet’s membrane (DM) were sutured to the recipient bed. Best spectacle-corrected visual acuity (BSCVA), refractive status, and intra- and postoperative complications were evaluated. Results Patients were male in 62.5%. Mean age of patients was 26.2±7.79 (range 15–46) years at the time of DALK and were followed for 23.07±8.1 (range 9–42) months. Mean BSCVA increased from 1.23±0.4 logMAR to 0.26±0.2 logMAR at final follow-up (PBared DM was achieved in 86 (82.7%) eyes. Main complications encountered included filamentary keratitis (19.2%), non-endothelial graft rejection (14.4%), and suture abscess (10.6%). Conclusion DALK using the bigbubble technique appears to be a safe and effective procedure in patients with keratoconus. PMID:23056667

  14. Image-guided modified deep anterior lamellar keratoplasty (DALK) corneal transplant using intraoperative optical coherence tomography

    Science.gov (United States)

    Tao, Yuankai K.; LaBarbera, Michael; Ehlers, Justis P.; Srivastava, Sunil K.; Dupps, William J.

    2015-03-01

    Deep anterior lamellar keratoplasty (DALK) is an alternative to full-thickness corneal transplant and has advantages including the absence of allograft rejection; shortened duration of topical corticosteroid treatment and reduced associated risk of glaucoma, cataract, or infection; and enables use of grafts with poor endothelial quality. DALK begins by performing a trephination of approximately 80% stromal thickness, as measured by pachymetry. After removal of the anterior stoma, a needle is inserted into the residual stroma to inject air or viscoelastic to dissect Descemet's membrane. These procedures are inherently difficult and intraoperative rates of Descemet's membrane perforation between 4-39% have been reported. Optical coherence tomography (OCT) provides high-resolution images of tissue microstructures in the cornea, including Descemet's membrane, and allows quantitation of corneal layer thicknesses. Here, we use crosssectional intraoperative OCT (iOCT) measurements of corneal thickness during surgery and a novel micrometeradjustable biopsy punch to precision-cut the stroma down to Descemet's membrane. Our prototype cutting tool allows us to establish a dissection plane at the corneal endothelium interface, mitigates variability in cut-depths as a result of tremor, reduces procedure complexity, and reduces complication rates. iOCT-guided modified DALK procedures were performed on 47 cadaveric porcine eyes by non-experts and achieved a perforation rate of ~5% with a mean corneal dissection time care.

  15. The Strip Module

    DEFF Research Database (Denmark)

    Pedersen, Tommy

    1996-01-01

    When the behaviour of a ship in waves is to be predicted it is convenient to have a tool which includes different approaches to the problem.The aim of this project is to develop such a tool named the strip theory module. The strip theory module will consist of submodules dependent on the I....... At last a postprocessor will be included with facilities for statistical calculations and for plots and prints of the results.The project is divided into 7 tasks where the third is to be completed.This report has two aims. To give an introduction to the project of developing a strip theory module......-ship code available at the department. It will be structured as a general preprocessor mainly to determine the hydrodynamic mass and damping. A strip processor including three different theories: A linear frequency domain strip theory, a quadratic strip theory and a nonlinear time domain strip theory...

  16. N-Isopropylacrylamide-co-glycidylmethacrylate as a Thermoresponsive Substrate for Corneal Endothelial Cell Sheet Engineering

    Directory of Open Access Journals (Sweden)

    Bernadette K. Madathil

    2014-01-01

    Full Text Available Endothelial keratoplasty is a recent shift in the surgical treatment of corneal endothelial dystrophies, where the dysfunctional endothelium is replaced whilst retaining the unaffected corneal layers. To overcome the limitation of donor corneal shortage, alternative use of tissue engineered constructs is being researched. Tissue constructs with intact extracellular matrix are generated using stimuli responsive polymers. In this study we evaluated the feasibility of using the thermoresponsive poly(N-isopropylacrylamide-co-glycidylmethacrylate polymer as a culture surface to harvest viable corneal endothelial cell sheets. Incubation below the lower critical solution temperature of the polymer allowed the detachment of the intact endothelial cell sheet. Phase contrast and scanning electron microscopy revealed the intact architecture, cobble stone morphology, and cell-to-cell contact in the retrieved cell sheet. Strong extracellular matrix deposition was also observed. The RT-PCR analysis confirmed functionally active endothelial cells in the cell sheet as evidenced by the positive expression of aquaporin 1, collagen IV, Na+-K+ ATPase, and FLK-1. Na+-K+ ATPase protein expression was also visualized by immunofluorescence staining. These results suggest that the in-house developed thermoresponsive culture dish is a suitable substrate for the generation of intact corneal endothelial cell sheet towards transplantation for endothelial keratoplasty.

  17. Animal study on transplantation of human umbilical vein endothelial cells for corneal endothelial decompensation

    Directory of Open Access Journals (Sweden)

    Li Cui

    2014-06-01

    Full Text Available AIM: To explore the feasibility of culturing human umbilical vein endothelial cells(HUVECon acellular corneal stroma and performing the posterior lamellar endothelial keratoplasty(PLEKtreating corneal endothelial decompensation.METHODS: Thirty New-Zealand rabbits were divided into three groups randomly, 10 rabbits for experimental group, 10 for stroma group and 10 for control group. Corneal endothelial cells were removed to establish animal model of corneal endothelial failure. PLEK was performed on the rabbits of experimental group and stroma group, and nothing was transplantated onto the rabbits of control group with the deep layer excised only. Postoperative observation was taken for 3mo. The degree of corneal edema and central corneal thickness were recorded for statistical analysis.RESULTS: Corneas in experimental group were relieved in edema obviously compared with that in stroma group and the control group, and showed increased transparency 7d after the operation. The average density of endothelial cells was 2 026.4±129.3cells/mm2, and average central corneal thickness was 505.2±25.4μm in experimental group, while 1 535.6±114.5μm in stroma group and 1 493.5±70.2μm in control group 3mo after operation.CONCLUSION:We achieved preliminary success in our study that culturing HUVEC on acellular corneal stroma and performing PLEK for corneal endothelial decompensation. HUVEC transplanted could survive in vivo, and have normal biological function of keeping cornea transparent. This study provides a new idea and a new way clinically for the treatment of corneal endothelial diseases.

  18. Endothelial dysfunction

    OpenAIRE

    Yaylalı, Yalın Tolga; Küçükaslan, Mete

    2011-01-01

    Endothelium is a multi-functional cluster of cells within the vascular system consisting of a single layer ofsquamous epithelium. Physiologically, endothelium performs various arrangement and protection functions.However, when these functions are disturbed toward derangement, endothelium also mediates pathologicalfunctions with negative effects on the body. Endothelial dysfunction is mediated by several mediators (nitricoxide, endothelins, prostaglandins, angiotensin 2, etc). Endothelial dysf...

  19. Anatomy Comic Strips

    Science.gov (United States)

    Park, Jin Seo; Kim, Dae Hyun; Chung, Min Suk

    2011-01-01

    Comics are powerful visual messages that convey immediate visceral meaning in ways that conventional texts often cannot. This article's authors created comic strips to teach anatomy more interestingly and effectively. Four-frame comic strips were conceptualized from a set of anatomy-related humorous stories gathered from the authors' collective…

  20. Science Comic Strips

    Science.gov (United States)

    Kim, Dae Hyun; Jang, Hae Gwon; Shin, Dong Sun; Kim, Sun-Ja; Yoo, Chang Young; Chung, Min Suk

    2012-01-01

    Science comic strips entitled Dr. Scifun were planned to promote science jobs and studies among professionals (scientists, graduate and undergraduate students) and children. To this end, the authors collected intriguing science stories as the basis of scenarios, and drew four-cut comic strips, first on paper and subsequently as computer files.…

  1. ALICE silicon strip module

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    This small silicon detector strip will be inserted into the inner tracking system (ITS) on the ALICE detector at CERN. This detector relies on state-of-the-art particle tracking techniques. These double-sided silicon strip modules have been designed to be as lightweight and delicate as possible as the ITS will eventually contain five square metres of these devices.

  2. Microkeratome-assisted lamellar keratoplasty for keratoconus: stromal sandwich.

    Science.gov (United States)

    Bilgihan, Kamil; Ozdek, Sengül C; Sari, Ayça; Hasanreisoglu, Berati

    2003-07-01

    To evaluate microkeratome-assisted lamellar keratoplasty for the treatment of keratoconus when it is not possible to correct the astigmatic ametropia with contact lenses. Ophthalmology Department, School of Medicine, Gazi University, Ankara, Turkey. This prospective study comprised 9 eyes of 7 keratoconus patients with contact lens intolerance. The donor cornea was prepared with a microkeratome and punched with a 7.25 mm or 7.50 mm trephine. Following the creation of a standard 9.0 mm corneal flap in the host cornea, the donor stromal button was implanted under this corneal flap like a sandwich. Transepithelial photorefractive keratectomy or laser in situ keratomileusis was performed when the corneal topography and refraction stabilized by the end of the sixth postoperative month. Follow-up ranged from 7 to 22 months. All patients gained 5 or more lines (mean 7.2 lines +/- 1.6 [SD]), and no patient lost a line of vision. The mean corneal thickness was 432.7 +/- 36.1 micrometers preoperatively and 578.1 +/- 45.1 micrometers after refractive surgery. The early visual results of this surgical technique are promising and seem to be comparable to those with penetrating keratoplasty.

  3. Aspergillus Flavus Keratitis after Deep Anterior Lamellar Keratoplasty

    Directory of Open Access Journals (Sweden)

    Mohammad-Reza Jafarinasab

    2012-01-01

    Full Text Available Purpose: To report the clinical, microbiologic, confocal scan and histopathologic features of Aspergillus flavus keratitis which developed immediately after deep anterior lamellar keratoplasty (DALK. Case Report: A 28-year-old woman underwent DALK using the big-bubble technique for keratoconus. The operation was uneventful, yielding a bare Descemet′s membrane (DM followed by transplantation of a corneal graft devoid of DM and endothelium. Four days after keratoplasty, mild infiltrates were noticed in the inferonasal margin of the graft, which rapidly progressed to involve the adjacent recipient cornea. Confocal scan findings suggested filamentous fungal keratitis, leading to initiation of topical and systemic antifungal medications followed by immediate replacement of the graft. Histopathologic examination disclosed keratitis caused by a filamentous fungus, which was determined by microbiologic cultures to be Aspergillus flavus. Early diagnosis and appropriate management resulted in complete recovery from this potentially devastating infection. Conclusion: Aspergillus Flavus can cause graft ulcers immediately after DALK. Confocal scan proved to be a valuable tool for early diagnosis and prompt intervention to control this otherwise devastating infection.

  4. Topography-guided LASIK with the wavelight laser after penetrating keratoplasty.

    Science.gov (United States)

    Cosar, C Banu; Acar, Suphi

    2006-09-01

    To report a case of topography-guided LASIK in a patient after previous penetrating keratoplasty. A 20-year-old man who had previous penetrating keratoplasty in his right eye for keratoconus and was intolerant to spectacles and contact lenses underwent topography-guided LASIK. Three months postoperatively, the patient's uncorrected visual acuity in the right eye was 20/25(+2). Best spectacle-corrected visual acuity was 20/20, with a manifest refraction of +0.25 -0.75 x 40 degree. Topography-guided LASIK is a useful therapeutic modality to address corneal irregularity after penetrating keratoplasty.

  5. Donor Descemet-off versus Descemet-on deep anterior lamellar keratoplasty: a confocal scan study.

    Science.gov (United States)

    Feizi, Sepehr; Zare, Mohammad; Hosseini, Seyed Bagher; Kanavi, Mozhgan Rezaee; Yazdani, Shahin

    2015-01-01

    To compare confocal features of grafts following deep anterior lamellar keratoplasty (DALK) using a donor without Descemet membrane (DM) versus a full-thickness donor with intact DM and endothelium. This retrospective comparative study examined 45 eyes from patients with keratoconus who underwent DALK using the big-bubble technique. The big-bubble technique yielded a bared DM in all keratoconic eyes. Twenty-seven eyes received tissue from a donor without DM (group 1), while 18 received tissue from a full-thickness donor with an intact DM and endothelium (group 2). A group of normal eyes (n = 28, group 3) served as controls. Confocal microscopy was used to determine keratocyte density, explore the donor-recipient interface including clarity and reflectivity, evaluate endothelial cell density and morphology, as well as measure interface depth and central corneal thickness. Mean follow-up duration was 20.2 ± 8.6 months and 29.6 ± 17.0 months in groups 1 and 2, respectively (p = 0.13). Confocal scan demonstrated that the keratocyte profiles and distribution were more similar to normal corneas in group 2. Significantly more severe interface haziness was observed when donor DM and endothelium was retained (mean interface reflectivity value of 102.7 ± 22.1 versus 161.7 ± 30.0 light reflectance units in groups 1 and 2, respectively, p<0.001). Graft cellular profiles and healing response at the donor-recipient interface can be profoundly affected depending on whether donor DM and endothelium is removed or retained.

  6. Human Bone Derived Collagen for the Development of an Artificial Corneal Endothelial Graft. In Vivo Results in a Rabbit Model.

    Directory of Open Access Journals (Sweden)

    Natalia Vázquez

    Full Text Available Corneal keratoplasty (penetrating or lamellar using cadaveric human tissue, is nowadays the main treatment for corneal endotelial dysfunctions. However, there is a worldwide shortage of donor corneas available for transplantation and about 53% of the world's population have no access to corneal transplantation. Generating a complete cornea by tissue engineering is still a tough goal, but an endothelial lamellar graft might be an easier task. In this study, we developed a tissue engineered corneal endothelium by culturing human corneal endothelial cells on a human purified type I collagen membrane. Human corneal endothelial cells were cultured from corneal rims after corneal penetrating keratoplasty and type I collagen was isolated from remnant cancellous bone chips. Isolated type I collagen was analyzed by western blot, liquid chromatography -mass spectrometry and quantified using the exponentially modified protein abundance index. Later on, collagen solution was casted at room temperature obtaining an optically transparent and mechanically manageable membrane that supports the growth of human and rabbit corneal endothelial cells which expressed characteristic markers of corneal endothelium: zonula ocluddens-1 and Na+/K+ ATPase. To evaluate the therapeutic efficiency of our artificial endothelial grafts, human purified type I collagen membranes cultured with rabbit corneal endothelial cells were transplanted in New Zealand white rabbits that were kept under a minimal immunosuppression regimen. Transplanted corneas maintained transparency for as long as 6 weeks without obvious edema or immune rejection and maintaining the same endothelial markers that in a healthy cornea. In conclusion, it is possible to develop an artificial human corneal endothelial graft using remnant tissues that are not employed in transplant procedures. This artificial endothelial graft can restore the integrality of corneal endothelium in an experimental model of

  7. [Rhegmatogenous retinal detachment in a patient with previous penetrating keratoplasty (clinical case)].

    Science.gov (United States)

    Burcea, M; Muşat, O; Gheorghe, Andreea; Mahdi, Labib; Colta, Diana; Cernat, Corina; Mansour, Agajani

    2014-01-01

    We present the case of a 54 year old patient diagnosed with rhegmatogenous retinal detachment and perforating keratoplasty. Surgery is recommended and we performed posterior vitrectomy, endolaser, and internal heavy oil tamponade. The post-operative course was favorable.

  8. A case of acute postoperative keratitis after deep anterior lamellar keratoplasty by multidrug resistant Klebsiella

    Directory of Open Access Journals (Sweden)

    Leena Bajracharya

    2015-01-01

    Full Text Available A healthy lady of 42 years underwent deep anterior lamellar keratoplasty for granular dystrophy. The very next day, it was complicated by development of infectious keratitis. The organism was identified as multidrug resistant Klebsiella pneumoniae. Donor corneal button may be implicated in the transmission of infection in an otherwise uneventful surgery and follow-up. Nosocomial infections are usually severe, rapidly progressive and difficult to treat. Finally, the lady had to undergo therapeutic penetrating keratoplasty for complete resolution of infection.

  9. Quantum strips on surfaces

    OpenAIRE

    Krejcirik, David

    2002-01-01

    Motivated by the theory of quantum waveguides, we investigate the spectrum of the Laplacian, subject to Dirichlet boundary conditions, in a curved strip of constant width that is defined as a tubular neighbourhood of an infinite curve in a two-dimensional Riemannian manifold. Under the assumption that the strip is asymptotically straight in a suitable sense, we localise the essential spectrum and find sufficient conditions which guarantee the existence of geometrically induced bound states. I...

  10. Excimer laser-assisted anterior lamellar keratoplasty for keratoconus, corneal problems after laser in situ keratomileusis, and corneal stromal opacities.

    Science.gov (United States)

    Bilgihan, Kamil; Ozdek, Sengül C; Sari, Ayça; Hasanreisoğlu, Berati

    2006-08-01

    To evaluate excimer laser-assisted anterior lamellar keratoplasty to augment thin corneas as in keratoconus ( .05). This technique presents a different modality for the treatment of keratoconus, post-LASIK corneal problems, and other corneal stromal opacities with anterior lamellar keratoplasty. Additional studies with more patients and longer follow-up will help determine the role of this technique as a substitute for penetrating keratoplasty in these patients.

  11. Comparison of contrast sensitivity and visual acuity between deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with keratoconus

    Directory of Open Access Journals (Sweden)

    Mehmet Orcun Akdemir

    2012-12-01

    Full Text Available AIM: To evaluate postoperative visual acuity and contrast sensitivity results following deep anterior lamellar keratoplasty (DALK and penetrating keratoplasty (PK in patients with keratoconus (KC. METHODS: All the patients’ records with KC who had PK or DALK surgery between May 2010 and May 2011 were retrospectively reviewed. Sixty patients who underwent successful corneal transplantation for KC: 30 eyes underwent DALK and 30 eyes underwent PK were included in this study. Preoperative and postoperative mean logarithm of the minimum angle of resolution (logMAR uncorrected visual acuity (UCVA, logMAR best spectacle-corrected visual acuity (BSCVA and intraocular pressure (IOP were evaluated. Contrast sensitivity tests (CS were done preoperative and 2 months after all sutures had removed. All surgeries were performed under regional anesthesia (retrobulbar anesthesia by 1 surgeon (B.K. who was experienced in penetrating and lamellar keratoplasty techniques.RESULTS: The mean age of the DALK group was 29.67±4.95 (range 18-40 years and the PK group was 28.7±3.53 (range 18-39 years. Preoperatively there was no significant difference in the logMAR UCVA, logMAR BSCVA and IOP between the DALK (1.281±0.56; 0.97±0.85; 12.07±2.12mmHg and PK (1.34±0.21; 0.98±0.21; 13±2.12mmHg groups. One-year after surgery there was no significant difference in the mean logMAR UCVA and IOP between the DALK (0.46±0.37; 11.73±2.1mmHg and PK (0.38±0.21; 12±2.12mmHg groups. The mean contrast sensitivity was evaluated by CC-100 Topcon LCD at 1.5, 2.52, 4.23, 7.10 and 11.91 cycles per degree (cs/deg spatial frequencies before and 2 months after the all sutures had removed. CONCLUSION: All patients with keratoconus in both DALK and PK groups performed good visual function postoperatively. The mean contrast sensitivity increased considerably at all spatial frequencies compared with preoperative levels in the DALK and PK groups. The mean post-operative evaluation of

  12. Novel spatula and dissector for safer deep anterior lamellar keratoplasty

    Directory of Open Access Journals (Sweden)

    Gustavo ,2,3 Bonfadini

    2014-10-01

    Full Text Available Objective: We describe a novel spatula and dissector to facilitate the big-bubble technique in deep anterior lamellar keratoplasty (DALK. Methods: A 29-year-old man who was diagnosed with bilateral keratoconus underwent deep anterior lamellar keratoplasty (DALK. After 350μm partial thickness incision of the recipient cornea, the Bonfadini dissector was inserted at the deepest point in the peripheral incision and could be advanced to the center of the cornea safely because of its "semi-sharp" tip. After achieving the big-bubble (BB separation of Descemet membrane (DM from the overlying stroma, the anterior stromal disc was removed. Viscoelastic material was placed on the stromal bed to prevent uncontrolled collapse and perforation of DM during the paracentesis blade incision into the BB. We could detect the safe opening of the BB using the Bonfadini dissector by the leakage of air bubbles into the viscoelastic material. After injecting viscoelastic material into the BB space, we inserted the Bonfadini spatula into the bigbubble safely because of its curved profile and blunt edges. The groove along the length of the Bonfadini spatula enables safe and efficient incision or the residual stromal tissue using the pointed end of a sharp blade while protecting the underlying DM. After removal of posterior stroma, the donor button was sutured with 16 interrupted 10-0 nylon sutures. Results: This technique and the use of the Bonfadini spatula and dissector facilitate exposure of Descemet membrane. Conclusion: The smooth Bonfadini DALK spatula and dissector facilitate safe and efficient completion of DALK surgery.

  13. Complications and Management of Deep Anterior Lamellar Keratoplasty

    Directory of Open Access Journals (Sweden)

    Banu Torun Acar

    2014-10-01

    Full Text Available Objectives: To report the intraoperative and postoperative follow-up complications and management of these in deep anterior lamellar keratoplasty (DALK surgery. Materials and Methods: Two hundred eighty-four eyes of 252 patients followed up in our cornea clinic who underwent DALK using Anwar’s big-bubble technique with healthy Descemet’s membrane and endothelium were included in this study. Intraoperative and postoperative complications as well as the management and treatment of these complications were evaluated. Results: Big bubble was created in 220 (77.5% eyes of 284 eyes, and lamellar dissection was performed in 64 (22.5% eyes. Perforation occurred during trephination in 4 eyes, and the procedure was accomplished by penetrating keratoplasty (PK. Intraoperative microperforation occurred in 44 eyes. Perforation enlarged in 4 eyes and PK was performed. Operation was continued in 40 eyes with air injection into the anterior chamber. In postopertive follow-up period, double anterior chamber (DAC occurred in 32 of 40 eyes. DAC spontaneously regressed in 8 eyes, and air was given into the anterior chamber with a second surgical intervention in 24 eyes. DAC improved in 20 eyes. Four eyes underwent PK. Fungal keratitis evolved at the interface in one eye, because of no healing during the follow-up period, this eye underwent PK under antifungal therapy. Eyes with interface haze and Descemet’s membrane folds were followed. Conclusion: DALK is a difficult technique with a steep learning curve. In addition to the complications seen in PK, specific complications can occur in lamellar surgery. (Turk J Ophthalmol 2014; 44: 337-40

  14. Clinical features of single and repeated globe rupture after penetrating keratoplasty

    Directory of Open Access Journals (Sweden)

    Murata N

    2013-03-01

    Full Text Available Noriaki Murata, Hideaki Yokogawa, Akira Kobayashi, Natsuko Yamazaki, Kazuhisa SugiyamaDepartment of Ophthalmology, Kanazawa University Graduate School of Medical Science, Kanazawa, JapanBackground: In this paper, we report our experience of the clinical features of single and repeated globe rupture after penetrating keratoplasty.Methods: We undertook a retrospective analysis of single and repeated globe ruptures following keratoplasty in eight eyes from seven consecutive patients referred to Kanazawa University Hospital over a 10-year period from January 2002 to March 2012. We analyzed their ophthalmic and demographic data, including age at time of globe rupture, incidence, time interval between keratoplasty and globe rupture, cause of rupture, complicated ocular damage, and visual outcome after surgical repair.Results: Five patients (71.4% experienced a single globe rupture and two patients (28.6% experienced repeated globe ruptures. Patient age at the time of globe rupture was 75.4 ± 6.8 (range 67–83 years. Four of the patients were men and three were women. During the 10-year study period, the incidence of globe rupture following penetrating keratoplasty was 2.8%. The time interval between penetrating keratoplasty and globe rupture was 101 ± 92 months (range 7 months to 23 years. The most common cause of globe rupture in older patients was a fall (n = 5, 79.8 ± 3.7 years, all older than 67 years. Final best-corrected visual acuity was .20/200 in three eyes (37.5%. In all except one eye, globe rupture involved the graft-host junction; in the remaining eye, the rupture occurred after disruption of the extracapsular cataract extraction wound by blunt trauma.Conclusion: Preventative measures should be taken to avoid single and repeated ocular trauma following penetrating keratoplasty.Keywords: repeated globe ruptures, penetrating keratoplasty, postoperative complications, ocular trauma

  15. Prosthetic Replacement of the Ocular Surface Ecosystem (PROSE) scleral device compared to keratoplasty for the treatment of corneal ectasia.

    Science.gov (United States)

    DeLoss, Karen S; Fatteh, Nadeem H; Hood, Christopher T

    2014-11-01

    To compare the ocular characteristics and visual outcomes of eyes with corneal ectasia that were fitted with the Prosthetic Replacement of the Ocular Surface Ecosystem (PROSE) scleral device to those that underwent keratoplasty. Retrospective, comparative case series. We reviewed the charts of consecutive patients with corneal ectasia that were evaluated for PROSE or underwent keratoplasty at our institution. Clinical data, topographic indices, and corneal thickness were reviewed, and eyes were stratified according to the Amsler-Krumeich classification for severity of ectasia. Only the more severe eye of each patient was included in the study. We compared visual acuity before and after PROSE fitting or keratoplasty. For PROSE evaluations, achievement of satisfactory fit and continued wear at 1 year of follow-up were recorded. From 2010 to 2012, 36 patients underwent PROSE evaluation for corneal ectasia while 37 patients underwent keratoplasty for the same indication. All eyes were successfully fitted with the PROSE device. Eyes in the keratoplasty group had more severe ectasia than eyes in the PROSE group (P = .038). Visual acuity was achieved more rapidly in the PROSE cohort compared to keratoplasty, and mean visual acuity was significantly better for all eyes (P ectasia (P ectasia achieved 20/25 visual acuity after PROSE than after keratoplasty (P = .003). At 1 year follow-up in the PROSE cohort, Snellen acuity was 20/28 (P = .108 vs keratoplasty), improving to 20/25 with over-refraction (P = .006 vs keratoplasty). Eyes with advanced corneal ectasia can be successfully fitted with the PROSE device, and the visual acuity outcome for stage 4 ectasia was better and more rapid compared to keratoplasty. The acuity remained excellent with 1 year of follow-up. PROSE evaluation should be considered in patients with advanced corneal ectasia before proceeding to keratoplasty, especially if the ectasia is deemed stable. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. micro strip gas chamber

    CERN Multimedia

    1998-01-01

    About 16 000 Micro Strip Gas Chambers like this one will be used in the CMS tracking detector. They will measure the tracks of charged particles to a hundredth of a millimetre precision in the region near the collision point where the density of particles is very high. Each chamber is filled with a gas mixture of argon and dimethyl ether. Charged particles passing through ionise the gas, knocking out electrons which are collected on the aluminium strips visible under the microscope. Such detectors are being used in radiography. They give higher resolution imaging and reduce the required dose of radiation.

  17. Visual rehabilitation using mini-scleral contact lenses after penetrating keratoplasty.

    Science.gov (United States)

    Rocha, Guilherme Andrade do Nascimento; Miziara, Patrícia Oliveira Braga; Castro, Ana Clara Vieira de; Rocha, Arthur Andrade do Nascimento

    2017-01-01

    To report the visual rehabilitation outcomes and complications of patients fitted with mini-scleral rigid gas-permeable (RGP) contact lenses (mini-SCLs) after penetrating keratoplasty. We retrospectively reviewed 27 eyes (21 patients) that were fitted with mini-SCLs between October 2013 and December 2014. We analyzed demographic data, previous corneal disorders, visual outcomes, interval from keratoplasty to contact lens fitting, topographic and specular microscope data, fitted contact lens parameters, and complications. The patients were divided into two groups according to the elapsed time since surgery: Group A, grafts with contact lens fitting was 10.6 ± 7.3 years (range: 1-29 years). The most frequent reason for keratoplasty was keratoconus (22 eyes, 81.4%). The mean contact lens-corrected visual acuity (CLCVA) was 0.09 ± 0.12 logMar (range: 0.50-0.00 logMar). The average topographic astigmatism, mean steepest keratometry (Kmax), and average cellularity on specular microscopy were 6.19 ± 3.49 diopters (D), 58.4 ± 7.8 D, and 1,231 ± 723 cells/mm2, respectively. Mini-SCL use allowed successful visual rehabilitation after corneal keratoplasty, particularly in patients who required corrective lenses for low visual acuity and were unable to wear RGP contact lenses. Our results indicate that mini-scleral lenses may be an option for the treatment of corneal irregularities, such as those associated with keratoplasty.

  18. Evaluation of corneal biomechanical properties following penetrating keratoplasty using ocular response analyzer

    Directory of Open Access Journals (Sweden)

    Vanathi Murugesan

    2014-01-01

    Full Text Available Purpose: To evaluate corneal biomechanical properties in eyes that has undergone penetrating keratoplasty (PK. Materials and Methods: Retrospective observational study in a tertiary care centre. Data recorded included ocular response analyzer (ORA values of normal and post-keratoplasty eyes [corneal hysteresis (CH, corneal resistance factor (CRF, Goldmann-correlated intraocular pressure (IOPg, and cornea-compensated intraocular pressure (IOPcc], corneal topography, and central corneal thickness (CCT. Wilcoxon signed rank test was used to analyze the difference in ORA parameter between post-PK eyes and normal eyes. Correlation between parameters was evaluated with Spearman′s rho correlation. Results: The ORA study of 100 eyes of 50 normal subjects and 54 post-keratoplasty eyes of 51 patients showed CH of 8.340 ± 1.85 and 9.923 ± 1.558, CRF of 8.846 ± 2.39 and 9.577 ± 1.631 in post-PK eyes and normal eyes, respectively. CH and CRF did not correlate with post-keratoplasty astigmatism (P = 0.311 and 0.276, respectively while a significant correlation was observed with IOPg (P = 0.004 and IOPcc (P < 0.001. Conclusion: Biomechanical profiles were significantly decreased in post-keratoplasty eyes with significant correlation with higher IOP as compared with that in normal eyes.

  19. ALICE Silicon Strip Detector

    CERN Multimedia

    Nooren, G

    2013-01-01

    The Silicon Strip Detector (SSD) constitutes the two outermost layers of the Inner Tracking System (ITS) of the ALICE Experiment. The SSD plays a crucial role in the tracking of the particles produced in the collisions connecting the tracks from the external detectors (Time Projection Chamber) to the ITS. The SSD also contributes to the particle identification through the measurement of their energy loss.

  20. Selective chemical stripping

    Science.gov (United States)

    Malavallon, Olivier

    1995-04-01

    At the end of the 80's, some of the large European airlines expressed a wish for paint systems with improved strippability on their aircraft, allowing the possibility to strip down to the primer without altering it, using 'mild' chemical strippers based on methylene chloride. These improvements were initially intended to reduce costs and stripping cycle times while facilitating rapid repainting, and this without the need to change the conventionally used industrial facilities. The level of in-service performance of these paint systems was to be the same as the previous ones. Requirements related to hygiene safety and the environment were added to these initial requirements. To meet customers' expectations, Aerospatiale, within the Airbus Industry GIE, formed a work group. This group was given the task of specifying, following up the elaboration and qualifying the paint systems allowing requirements to be met, in relation with the paint suppliers and the airlines. The analysis made in this report showed the interest of transferring as far upstream as possible (to paint conception level) most of the technical constraints related to stripping. Thus, the concept retained for the paint system, allowing selective chemical stripping, is a 3-coat system with characteristics as near as possible to the previously used paints.

  1. Penetrating keratoplasty for perforated corneal ulcers under topical anesthesia.

    Science.gov (United States)

    Mannan, Rashim; Sharma, Namrata; Pruthi, Archna; Maharana, Prafulla K; Vajpayee, Rasik B

    2013-11-01

    To evaluate the structural and functional outcomes of eyes with perforated corneal ulcers undergoing penetrating keratoplasty (PKP) under topical anesthesia. A prospective analysis of 17 consecutive cases that underwent PKP under topical anesthesia, where infiltrative anesthesia was contraindicated or general anesthesia could not be given for medical reasons or was not available for logistical reasons. Seventeen eyes of 15 patients with a mean age of 47.3 ± 16.2 years underwent a PKP for treating perforated corneal ulcers under topical anesthesia. Perforation involved the pupillary zone in 13 (76.5%) cases. Preoperatively, 8 patients (47.1%) were phakic, 8 (47.1%) were pseudophakic, and 1 (5.9%) was aphakic. The PKP was completed successfully in all the eyes. An anterior capsular tear occurred in 3 eyes (17.6%). A posterior chamber intraocular implant was put in 1 eye, and 2 eyes were found to be aphakic. The patients reported mild to moderate discomfort and tolerated the procedure well. At the final follow-up, 10 patients had clear grafts (58.8%), and 7 patients (41.2%) had partially clear grafts. The best-corrected visual acuity was better than 6/18 in 10 eyes and between 6/60 and 6/24 in 7 eyes. PKP can be performed successfully under topical anesthesia in cooperative patients who have perforated corneal ulcers.

  2. Toxic anterior segment syndrome following deep anterior lamellar keratoplasty

    Directory of Open Access Journals (Sweden)

    Neslihan Sevimli

    Full Text Available ABSTRACT We present the case of a 31-year-old patient with toxic anterior segment syndrome (TASS that developed after undergoing deep anterior lamellar keratoplasty (DALK. She had keratoconus, and despite wearing hard contact lenses for many years in the left eye, her vision had deteriorated; therefore, DALK was performed on this eye. The preoperative visual acuity (VA was finger counting at 3 m. Routine DALK was performed using the "big-bubble" technique. The corneal entry incision was hydrated at the end of the surgery, which was terminated by air injection into the anterior chamber. On postoperative day 1, VA was at the level of hand movements, and the cornea was edematous. Topical high-dose dexamethasone and oral steroids were initiated considering the diagnosis of TASS. Subsequently, the patient's VA increased, and the corneal edema decreased. We believe that the use of re-sterilized cannulas may have been the likely cause of TASS. Although DALK can be performed without interfering with the anterior chamber, one should keep in mind that TASS may occur in response to the solution used to hydrate the incision site and the air injected into the anterior chamber.

  3. Diagnosis and Management of Iridocorneal Endothelial Syndrome

    Directory of Open Access Journals (Sweden)

    Marta Sacchetti

    2015-01-01

    Full Text Available The iridocorneal endothelial (ICE syndrome is a rare ocular disorder that includes a group of conditions characterized by structural and proliferative abnormalities of the corneal endothelium, the anterior chamber angle, and the iris. Common clinical features include corneal edema, secondary glaucoma, iris atrophy, and pupillary anomalies, ranging from distortion to polycoria. The main subtypes of this syndrome are the progressive iris atrophy, the Cogan-Reese syndrome, and the Chandler syndrome. ICE syndrome is usually diagnosed in women in the adult age. Clinical history and complete eye examination including tonometry and gonioscopy are necessary to reach a diagnosis. Imaging techniques, such as in vivo confocal microscopy and ultrasound biomicroscopy, are used to confirm the diagnosis by revealing the presence of “ICE-cells” on the corneal endothelium and the structural changes of the anterior chamber angle. An early diagnosis is helpful to better manage the most challenging complications such as secondary glaucoma and corneal edema. Treatment of ICE-related glaucoma often requires glaucoma filtering surgery with antifibrotic agents and the use of glaucoma drainage implants should be considered early in the management of these patients. Visual impairment and pain associated with corneal edema can be successfully managed with endothelial keratoplasty.

  4. Diagnosis and Management of Iridocorneal Endothelial Syndrome

    Science.gov (United States)

    Sacchetti, Marta; Mantelli, Flavio; Macchi, Ilaria; Ambrosio, Oriella; Rama, Paolo

    2015-01-01

    The iridocorneal endothelial (ICE) syndrome is a rare ocular disorder that includes a group of conditions characterized by structural and proliferative abnormalities of the corneal endothelium, the anterior chamber angle, and the iris. Common clinical features include corneal edema, secondary glaucoma, iris atrophy, and pupillary anomalies, ranging from distortion to polycoria. The main subtypes of this syndrome are the progressive iris atrophy, the Cogan-Reese syndrome, and the Chandler syndrome. ICE syndrome is usually diagnosed in women in the adult age. Clinical history and complete eye examination including tonometry and gonioscopy are necessary to reach a diagnosis. Imaging techniques, such as in vivo confocal microscopy and ultrasound biomicroscopy, are used to confirm the diagnosis by revealing the presence of “ICE-cells” on the corneal endothelium and the structural changes of the anterior chamber angle. An early diagnosis is helpful to better manage the most challenging complications such as secondary glaucoma and corneal edema. Treatment of ICE-related glaucoma often requires glaucoma filtering surgery with antifibrotic agents and the use of glaucoma drainage implants should be considered early in the management of these patients. Visual impairment and pain associated with corneal edema can be successfully managed with endothelial keratoplasty. PMID:26451377

  5. [Toric add-on intraocular lenses for correction of high astigmatism after pseudophakic keratoplasty].

    Science.gov (United States)

    Hassenstein, A; Niemeck, F; Giannakakis, K; Klemm, M

    2017-06-01

    Perforating keratoplasty shows good morphological results with a clear cornea; however, a limiting factor is often the resulting astigmatism, which cannot be corrected with either glasses or contact lenses (CL) in up to 20% of the patients. We retrospectively investigated 15 patients after pseudophakic perforating keratoplasty, who received implantation of toric add-on intraocular lenses (IOL) to correct astigmatism. The mean preoperative astigmatism of 6.5 diopter (dpt) could be reduced to a mean postoperative value of 1.0 dpt. The mean visual acuity could be improved from a preoperative value of sc one case of a lens extension tear. Based on our good experiences we now provide toric add-on IOL to all patients with pseudophakic perforating keratoplasty when this cannot be corrected or only insufficiently corrected by conservative methods.

  6. Deep anterior lamellar keratoplasty for the management of iatrogenic keratectasia occurring after hexagonal keratotomy

    Science.gov (United States)

    Mehta, Paras; Rathi, Varsha M; Murthy, Somasheila I

    2012-01-01

    Iatrogenic keratectasia has been reported subsequent to refractive surgery or trauma. Hexagonal keratotomy (HK) is a surgical incisional technique to correct hyperopia. A number of complications have been reported following this procedure, including irregular astigmatism, wound healing abnormalities and corneal ectasia. When visual acuity is poor because of ectasia or irregular astigmatism and contact lens fitting is not possible, penetrating or lamellar keratoplasty can be performed. Since incisions in refractive keratotomy are set at 90–95% depth of cornea, intraoperative microperforations are known to occur and lamellar keratoplasty may become difficult. We describe deep anterior lamellar keratoplasty (DALK) used to successfully manage keratectasia after HK. Pre DALK vision was 20/400 and post DALK vision was 20/30 two months after surgery. This report aims to show improved visual outcome in corneal ectasia secondary to HK. DALK can be a procedure of choice with proper case selection. PMID:22446912

  7. Corneal ectasia after laser in situ keratomileusis after laser thermal keratoplasty.

    Science.gov (United States)

    Nguyen, Myhanh T; Hamilton, David Rex

    2009-02-01

    To report a case of corneal ectasia following hyperopic laser in situ keratomileusis in a patient who had previous laser thermal keratoplasty. Case report. We report a case of a 66-year-old emmetropic man initially presented with complaint of difficulty reading without correction. Laser thermal keratoplasty (LTK) was performed on the non-dominant right eye, resulting in successful monovision. Three years later, the patient presented with decreased unaided near vision caused by hyperopic regression of the LTK. Conventional hyperopic laser in situ keratomileusis (LASIK) was performed, again resulting in successful monovision. More than three years later, the patient returned with worsening near vision. A focal corneal ectasia was noted in the same location as the 6 o'clock LTK leukoma. To our knowledge, this is the first report of ectasia occuring after LASIK following LTK. Consideration should be given to performing photorefractive keratectomy (PRK) instead of LASIK following thermal keratoplasty.

  8. Femtosecond laser-assisted keratoplasty in a child with corneal opacity:case report

    Directory of Open Access Journals (Sweden)

    E. Yu. Markova

    2014-01-01

    Full Text Available Corneal opacities are the fourth cause of blindness world-wide. Over the past two centuries, various corneal transplantation (i.e., keratoplasty methods have been developed and improved. Nowadays, femtolaserssisted keratoplasty is one of most promising techniques. Femtosecond laser have several advantages that provide additional surgical benefits. Among them, no thermal injury, the ability to cut deeply on a single plane and to perform various corneal profiles should be mentioned. In children, corneal disorders are of special importance while femtosecondassisted keraatoplasty case reports are rare. Here, we describe femtosecond laserssisted penetrating keratoplasty in a girl with a rough central corneal opacity.

  9. Deep Anterior Lamellar Keratoplasty Using the Big-Bubble Technique in Keratoconus

    Directory of Open Access Journals (Sweden)

    Mohammad-Ali Javadi

    2009-01-01

    Full Text Available

    PURPOSE: To evaluate the visual outcomes and complications of deep anterior lamellar keratoplasty (DALK using the big-bubble technique in patients with keratoconus. METHODS: In this case series, 104 eyes of 99 patients with moderate to advanced keratoconus underwent DALK. All subjects were contact lens intolerant or had unacceptable spectacle-corrected visual acuity. DALK was performed using the big-bubble technique. Full thickness donor corneas devoid of Descemet's membrane (DM were sutured to the recipient bed. Best spectacle-corrected visual acuity (BSCVA, refractive status, and intra- and postoperative complications were evaluated. RESULTS: Patients were male in 62.5%. Mean age of patients was 26.2±7.79 (range 15-46 years at the time of DALK and were followed for 23.07±8.1 (range 9-42 months. Mean BSCVA increased from 1.23±0.4 logMAR to 0.26±0.2 logMAR at final follow-up (P < 0.001. Postoperative mean spherical equivalent refractive error and refractive and keratometric astigmatism were -3.41±3.1 D, 3.07±2.4 D, and 3.64±2.2 D, respectively. Bared DM was achieved in 86 (82.7% eyes. Main complications encountered included filamentary keratitis (19.2%, non-endothelial graft rejection (14.4%, and suture abscess (10.6%. CONCLUSIONS: DALK using the big-bubble technique appears to be a safe and effective procedure in

  10. Noncontact laser photothermal keratoplasty. II: Refractive effects and treatment parameters in cadaver eyes.

    Science.gov (United States)

    Simon, G; Ren, Q; Parel, J M

    1994-01-01

    Noncontact laser photothermal keratoplasty may provide a new alternative for the treatment of myopia, hyperopia, and astigmatism. The purpose of this article is to study the refractive effect that laser photoablation keratoplasty is capable of producing on a normal human cadaver cornea, including the relationship between the keratometric changes and laser treatment parameters. The human cadaver eyes were treated with a holmium laser (pulsed Ho:YAG, 2.10 microns, 250 microseconds) coupled to a maskable, polyprismatic delivery system mounted on either an optical bench or a slit-lamp microscope. Using a topographic videokeratography system, we first investigated the refractive effect that noncontact laser photothermal keratoplasty would produce on a normal cadaver cornea. We then studied the keratometric changes produced by different radiant exposure levels at a fixed treatment pattern, as well as by different treatment patterns at a fixed radiant exposure level. Finally, we studied the possible therapeutic application of laser photothermal keratoplasty for correcting high postoperative astigmatism on a cadaver eye model. For the single-pulse 3-millimeter ring of eight-spot treatment, the keratometric power of the cornea initially increased with the radiant exposure and peaked at 26 J/cm2. The refractive effect was increased by projecting an additional set of eight spots equidistant between the first eight spots on the same diameter ring. Eighteen J/cm2 was the minimal radiant exposure required to produce consistent and predictable keratometric changes. The corneas were flattened using treatment patterns smaller than or equal to 3 mm in diameter and steepened using treatment patterns larger than or equal to 5 mm in diameter. A transition zone between 4 and 5 mm was observed in which minimal and unpredictable keratometric changes of the central cornea occurred. The surgically-induced astigmatism (> 10.00 D) was corrected by progressive laser photothermal keratoplasty

  11. Photosensitive Strip RETHGEM

    CERN Document Server

    Peskov, Vladimir; Nappi, E.; Oliveira, R.; Paic, G.; Pietropaolo, F.; Picchi, P.

    2008-01-01

    An innovative photosensitive gaseous detector, consisting of a GEM like amplification structure with double layered electrodes (instead of commonly used metallic ones) coated with a CsI reflective photocathode, is described. In one of our latest designs, the inner electrode consists of a metallic grid and the outer one is made of resistive strips; the latter are manufactured by a screen printing technology on the top of the metallic strips grid The inner metallic grid is used for 2D position measurements whereas the resistive layer provides an efficient spark protected operation at high gains - close to the breakdown limit. Detectors with active areas of 10cm x10cm and 10cm x20cm were tested under various conditions including the operation in photosensitive gas mixtures containing ethylferrocene or TMAE vapors. The new technique could have many applications requiring robust and reliable large area detectors for UV visualization, as for example, in Cherenkov imaging devices.

  12. Alcohol Saliva Strip Test

    OpenAIRE

    Thokala, Madhusudhana Rao; Dorankula, Shyam Prasad Reddy; Muddana, Keertrthi; Velidandla, Surekha Reddy

    2014-01-01

    Alcohol is a factor in many categories of injury. Alcohol intoxication is frequently associated with injuries from falls, fires, drowning, overdoses, physical and sexual abusements, occupational accidents, traffic accidents and domestic violence. In many instances, for forensic purpose, it may be necessary to establish whether the patients have consumed alcohol that would have been the reason for the injury/accidents. Combining rapidity and reliability, alcohol saliva strip test (AST) has bee...

  13. Da Vinci Xi Robot-Assisted Penetrating Keratoplasty.

    Science.gov (United States)

    Chammas, Jimmy; Sauer, Arnaud; Pizzuto, Joëlle; Pouthier, Fabienne; Gaucher, David; Marescaux, Jacques; Mutter, Didier; Bourcier, Tristan

    2017-06-01

    This study aims (1) to investigate the feasibility of robot-assisted penetrating keratoplasty (PK) using the new Da Vinci Xi Surgical System and (2) to report what we believe to be the first use of this system in experimental eye surgery. Robot-assisted PK procedures were performed on human corneal transplants using the Da Vinci Xi Surgical System. After an 8-mm corneal trephination, four interrupted sutures and one 10.0 monofilament running suture were made. For each procedure, duration and successful completion of the surgery as well as any unexpected events were assessed. The depth of the corneal sutures was checked postoperatively using spectral-domain optical coherence tomography (SD-OCT). Robot-assisted PK was successfully performed on 12 corneas. The Da Vinci Xi Surgical System provided the necessary dexterity to perform the different steps of surgery. The mean duration of the procedures was 43.4 ± 8.9 minutes (range: 28.5-61.1 minutes). There were no unexpected intraoperative events. SD-OCT confirmed that the sutures were placed at the appropriate depth. We confirm the feasibility of robot-assisted PK with the new Da Vinci Surgical System and report the first use of the Xi model in experimental eye surgery. Operative time of robot-assisted PK surgery is now close to that of conventional manual surgery due to both improvement of the optical system and the presence of microsurgical instruments. Experimentations will allow the advantages of robot-assisted microsurgery to be identified while underlining the improvements and innovations necessary for clinical use.

  14. Da Vinci Xi Robot–Assisted Penetrating Keratoplasty

    Science.gov (United States)

    Chammas, Jimmy; Sauer, Arnaud; Pizzuto, Joëlle; Pouthier, Fabienne; Gaucher, David; Marescaux, Jacques; Mutter, Didier; Bourcier, Tristan

    2017-01-01

    Purpose This study aims (1) to investigate the feasibility of robot-assisted penetrating keratoplasty (PK) using the new Da Vinci Xi Surgical System and (2) to report what we believe to be the first use of this system in experimental eye surgery. Methods Robot-assisted PK procedures were performed on human corneal transplants using the Da Vinci Xi Surgical System. After an 8-mm corneal trephination, four interrupted sutures and one 10.0 monofilament running suture were made. For each procedure, duration and successful completion of the surgery as well as any unexpected events were assessed. The depth of the corneal sutures was checked postoperatively using spectral-domain optical coherence tomography (SD-OCT). Results Robot-assisted PK was successfully performed on 12 corneas. The Da Vinci Xi Surgical System provided the necessary dexterity to perform the different steps of surgery. The mean duration of the procedures was 43.4 ± 8.9 minutes (range: 28.5–61.1 minutes). There were no unexpected intraoperative events. SD-OCT confirmed that the sutures were placed at the appropriate depth. Conclusions We confirm the feasibility of robot-assisted PK with the new Da Vinci Surgical System and report the first use of the Xi model in experimental eye surgery. Operative time of robot-assisted PK surgery is now close to that of conventional manual surgery due to both improvement of the optical system and the presence of microsurgical instruments. Translational Relevance Experimentations will allow the advantages of robot-assisted microsurgery to be identified while underlining the improvements and innovations necessary for clinical use. PMID:28660096

  15. Shifting trends in microbial keratitis following penetrating keratoplasty in Taiwan.

    Science.gov (United States)

    Chen, Hung-Chi; Lee, Chia-Yi; Lin, Hung-Yu; Ma, David Hui-Kang; Chen, Phil Yeong-Fong; Hsiao, Ching-Hsi; Lin, Hsin-Chiung; Yeh, Lung-Kun; Tan, Hsin-Yuan

    2017-02-01

    To investigate the clinical and microbiological profiles from microbial keratitis following penetrating keratoplasty (PKP) in a tertiary referral center in Taiwan, the medical records of 648 consecutive patients (648 eyes) undergoing PKP between January 2003 and December 2007 were retrospectively reviewed. Patients who subsequently sustained microbial keratitis were enrolled and analyzed for potential risk factors, clinical manifestations, microbiological profiles, complications, graft survival, and final visual outcome. A total number of 42 corneal graft infections (6.5%) were recruited. Mean interval between corneal transplantation and graft infection was 12 ± 9.5 months. Potential risk factors included suture-related problems (31.0%), lid abnormalities (23.8%), persistent epithelial defect (23.8%), contact lens use (14.3%), dry eye (11.9%), and prior rejection episodes (4.8%). Lesions were discovered mostly at the donor-recipient junction ([DRJ] 45.2%). Positive cultures were identified in all of the morbid eyes, of which Pseudomonas aeruginosa was the most common pathogen (38.1%). Despite mandatory hospitalization and topical fortified antibiotics management, complications ensued such as graft failure (71.4%), hypopyon (21.4%), corneal perforation (14.3%), wound dehiscence (11.9%), and endophthalmitis (4.8%). The visual outcome was dismal that graft clarity was achieved in only 12 eyes (28.6%), and that final visual acuity deteriorated to less than 20/200 in 28 eyes (66.7%). In conclusion, microbial keratitis following PKP is a devastating event that severely impairs graft survival rate and postoperative visual outcome which usually occur within the first postoperative year. The incidence of post-PKP microbial keratitis has generally decreased in recent years whilst P. aeroginosa prevails as the leading cause of graft infection in our hospital. Close follow-up by ophthalmologists and elevated self-awareness of patients for at least one year are always

  16. Photorefractive keratectomy for post-penetrating keratoplasty myopia and astigmatism.

    Science.gov (United States)

    Bilgihan, K; Ozdek, S C; Akata, F; Hasanreisoğlu, B

    2000-11-01

    To determine the safety, effectiveness, and predictability of photorefractive keratectomy (PRK) for the correction of myopia and astigmatism after penetrating keratoplasty. Gazi University, Medical School, Department of Ophthalmology, Ankara, Turkey. Photorefractive keratectomy was performed in 16 eyes of 16 patients with postkeratoplasty myopia and astigmatism who were unable to wear glasses due to anisometropia and were contact lens intolerant. They were examined for uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and corneal transplant integrity before and after surgery. The mean follow-up after PRK was 26.0 months +/- 15.7 (SD) (range 12 to 63 months). The mean preoperative spherical equivalent refraction of -4.47 +/- 1.39 diopters (D) was -3.39 +/- 1.84 D (P >.05) at the last postoperative visit and the mean preoperative cylinder of -5.62 +/- 2.88 D was -3.23 +/- 1.70 D (P <.05); refractive regression correlated with the amount of ablation performed. The BSCVA decreased in 3 eyes (18.8%), and the UCVA decreased in 2 (12.5%). Six eyes (37.5%) had grade 2 to 3 haze, which resolved spontaneously in 4 eyes within a relatively long time but caused a decrease in BSCVA in 2 (12.5%). Two of the eyes (12.5%) had a rejection episode after PRK and were successfully treated with topical steroids. Photorefractive keratectomy to correct postkeratoplasty myopia and astigmatism appears to be less effective and less predictable than PRK for naturally occurring myopia and astigmatism. Corneal haze and refractive regression are more prevalent, and patient satisfaction is not good.

  17. Use of Scleral Lenses and Miniscleral Lenses After Penetrating Keratoplasty.

    Science.gov (United States)

    Barnett, Melissa; Lien, Vivian; Li, Jennifer Y; Durbin-Johnson, Blythe; Mannis, Mark J

    2016-05-01

    To examine the clinical outcomes of scleral lenses for visual rehabilitation after penetrating keratoplasty (PK). A retrospective review was conducted for 34 patients (48 eyes) who had a history of prior PK and were fit with scleral lenses between October 2009 and December 2013 at the UC Davis Eye Center. The most common initial indication for PK was keratoconus in 27 eyes (56%). Thirty-three eyes (69%) had previously been fit with other types of contact lenses, with small-diameter rigid gas-permeable lenses being the most common. The improvement in best-corrected visual acuity with a scleral lens compared with prior spectacle refraction or other contact lens was a mean of two best-corrected visual acuity lines. Forty-four eyes (91.7%) achieved functional vision with best scleral lens-corrected visual acuities of 20/40 or better. Patients who continued wearing scleral lenses were significantly more likely to report "good" subjective vision compared with patients who abandoned scleral lens wear (P=0.009), although change in objective best-corrected visual acuity did not differ significantly. There were no cases of infectious keratitis. Six eyes (12.5%) developed graft rejection; 3 were able to resume scleral lens wear. Nineteen eyes (39.5%) discontinued scleral lens wear for various reasons, the most common reason for discontinuation of lens wear was difficulty with scleral lens insertion or removal (8 eyes, 42.1%). Scleral lenses are effective and safe in patients who have had PK. There was a mean gain in visual acuity, with the majority of patients achieving 20/40 vision or better. The patient's subjective perception of vision was a significant factor in determining whether scleral lens wear was continued or abandoned.

  18. Treatment of acanthamoeba keratitis with intravenous pentamidine before therapeutic keratoplasty.

    Science.gov (United States)

    Sacher, Bradley A; Wagoner, Michael D; Goins, Kenneth M; Sutphin, John E; Greiner, Mark A; Kitzmann, Anna S

    2015-01-01

    The aim of this study was to evaluate the outcome of pretreatment of Acanthamoeba keratitis with intravenous pentamidine (IVP) before therapeutic keratoplasty (TKP). A retrospective chart review was performed of the medical records of every patient treated with IVP before TKP for Acanthamoeba keratitis at a single, tertiary care eye center between January 1, 2002, and December 31, 2012. The main outcome measures were microbiological cure, graft survival, and visual outcome. Eight eyes of 7 patients met the inclusion criteria. Preoperatively, all 8 eyes had failed traditional antiamoebic therapy, including 5 eyes with recurrent infections after previous TKP. The patients were treated with IVP (190-400 mg/d) for a median of 14 days (range, 7-26 days). After 8 TKP, a microbiological cure was achieved, and a clear graft was maintained in 5 (62.5%) eyes during a mean follow-up interval of 31.2 months (range, 1.0-95.7 months). Repeat TKP in 3 eyes with recurrent Acanthamoeba keratitis resulted in 2 additional microbiological cures and 1 more clear graft. The final best-corrected visual acuity was ≥20/40 in 5 (62.5%) eyes and worse than 20/200 in 3 eyes. Overall, the final vision was improved in 6 (75.0%) eyes, remained the same in 1 (12.5%) eye, and was worse in 1 (12.5%) eye. The adjunctive use of IVP before TKP may assist with the achievement of microbiological cure, clear graft, and good visual outcome in a majority of eyes with Acanthamoeba keratitis.

  19. The suitability of corneas stored by organ culture for penetrating keratoplasty and influence of donor and recipient factors on 5-year graft survival.

    Science.gov (United States)

    Armitage, W John; Jones, Mark N A; Zambrano, Isaac; Carley, Fiona; Tole, Derek M

    2014-02-10

    To determine the impact of donor factors on the suitability of corneas stored by organ culture for penetrating keratoplasty (PK) and the influence of donor and recipient factors on 5-year survival of first PK. Logistic regression analyses were carried out to determine the influence of donor factors on, respectively, the risk of microbial contamination during organ culture, the suitability of corneas for PK (endothelial cell density ≥ 2200 cells/mm(2)), and the quality of corneas (endothelial cell density ≥ 2500 cells/mm(2)). Only one cornea, randomly selected, from each donor was included in these analyses. A Cox regression analysis was used to determine the influence of donor and recipient factors on 5-year PK survival. Risk of contamination (n = 8317): Causes of donor death including infection, respiratory disease, and cancer all increased the risk of contamination during organ culture (P Donor age (P organ culture (P organ donors were more likely to be suitable for PK (P = 0.0003). Five-year graft survival (n = 3014): Graft survival was dominated by the indication for PK (P donor factor affecting survival was sex (P = 0.008). Donor age and storage time but not postmortem times influenced the suitability of corneas for PK. The indication for PK and other recipient factors were the main predictors of graft failure.

  20. Keratomycosis caused by Acremonium Recifei, treated with keratoplasty, Miconazole and Ketoconazole

    NARCIS (Netherlands)

    H.J. Simonsz (Huib)

    1983-01-01

    textabstractA patient is discussed who developed a fungal corneal ulcer due to Acremonium (Cephalosporium) Recifei after a piece of a coconut flew into his eye while he was cracking it. Treatment consisted of keratoplasty, Miconazole as ointment and intravenously, and Ketaconazole orally. Diagnosis

  1. Penetrating keratoplasty for treatment of corneal abscesses in horses – case report

    Directory of Open Access Journals (Sweden)

    Zita Makra

    2013-01-01

    Full Text Available This case report describes the surgical technique and outcome of allograft transplantation to treat full thickness corneal abscesses in three horses. In all three cases penetrating keratoplasty was performed. Each affected eye had an abscess within the corneal stroma. An initial full thickness circular corneal incision was made around the lesion. After excision of the stromal abscess the created defect was replaced with a larger diameter full thickness donor graft and the initial corneal incision was repaired. All of the horses that underwent penetrating keratoplasty procedure healed with a scar at the graft site and remained visual. Penetrating keratoplasty is an effective technique for surgical removal of medically nonresponsive full thickness stromal abscess in horses and results in a visual and cosmetically acceptable globe. The advantages of this technique compared to medical therapy are that there is less scarring, shorter healing times and less damage of the globe because of the concurrent uveitis. To the authors’ knowledge, clinical experience with penetrating keratoplasty in horses has not been reported in Europe so far.

  2. Indications and outcomes of pediatric keratoplasty in a tertiary eye care center: A retrospective review.

    Science.gov (United States)

    Gulias-Cañizo, Rosario; Gonzalez-Salinas, Roberto; Hernandez-Zimbron, Luis Fernando; Hernandez-Quintela, Everardo; Sanchez-Huerta, Valeria

    2017-11-01

    To evaluate indications and outcomes of pediatric keratoplasty in a tertiary eye center, and identify factors that affect visual outcomes.We performed a retrospective review of penetrating keratoplasty in children aged 0 to 18 years between 1995 and 2011 in the Asociación para Evitar la Ceguera en México IAP, Hospital "Dr. Luis Sánchez Bulnes".A total of 574 penetrating keratoplasties were performed during the study interval. Median follow-up was 5.0 years. Main indications included keratoconus (55.58%), postherpetic scarring (9.58%), traumatic opacities (7.49%), and bullous keratopathy (6.09%). Rejection rates at 5 years were 27% overall, and among indications, keratoconus showed the best graft survival at 60-months follow-up (85%). The percentage of patients with best corrected visual acuity (BCVA) posttransplant >20/400 at 5 years in the nonrejection group was 81.25% and 82.74% in 10 years of age (YOA) groups, respectively, versus a BCVA posttransplant > 20/400 at 5 years in the rejection group of 53.68% and 51.72% in 10 YOA groups, respectively. There was a statistically significant reduced rejection rate between genders at 18 months of follow-up, favoring males.Despite being considered a high-risk procedure in children, penetrating keratoplasty can achieve good results, especially in patients with keratoconus. It can achieve significative improvements of visual acuity, provided there is an adequate follow-up and treatment adherence.

  3. Spray Rolling Aluminum Strip

    Energy Technology Data Exchange (ETDEWEB)

    Lavernia, E.J.; Delplanque, J-P; McHugh, K.M.

    2006-05-10

    Spray forming is a competitive low-cost alternative to ingot metallurgy for manufacturing ferrous and non-ferrous alloy shapes. It produces materials with a reduced number of processing steps, while maintaining materials properties, with the possibility of near-net-shape manufacturing. However, there are several hurdles to large-scale commercial adoption of spray forming: 1) ensuring strip is consistently flat, 2) eliminating porosity, particularly at the deposit/substrate interface, and 3) improving material yield. Through this program, a new strip/sheet casting process, termed spray rolling, has been developed, which is an innovative manufacturing technique to produce aluminum net-shape products. Spray rolling combines the benefits of twin-roll casting and conventional spray forming, showing a promising potential to overcome the above hurdles associated with spray forming. Spray rolling requires less energy and generates less scrap than conventional processes and, consequently, enables the development of materials with lower environmental impacts in both processing and final products. Spray Rolling was developed as a collaborative project between the University of California-Davis, the Colorado School of Mines, the Idaho National Engineering and Environmental Laboratory, and an industry team. The following objectives of this project were achieved: (1) Demonstration of the feasibility of the spray rolling process at the bench-scale level and evaluation of the materials properties of spray rolled aluminum strip alloys; and (2) Demonstration of 2X scalability of the process and documentation of technical hurdles to further scale up and initiate technology transfer to industry for eventual commercialization of the process.

  4. Dynamic Underground Stripping Project

    International Nuclear Information System (INIS)

    Aines, R.; Newmark, R.; McConachie, W.; Udell, K.; Rice, D.; Ramirez, A.; Siegel, W.; Buettner, M.; Daily, W.; Krauter, P.; Folsom, E.; Boegel, A.J.; Bishop, D.; Udell, K.

    1992-01-01

    LLNL is collaborating with the UC Berkeley College of Engineering to develop and demonstrate a system of thermal remediation and underground imaging techniques for use in rapid cleanup of localized underground spills. Called ''Dynamic Stripping'' to reflect the rapid and controllable nature of the process, it will combine steam injection, direct electrical heating, and tomographic geophysical imaging in a cleanup of the LLNL gasoline spill. In the first 8 months of the project, a Clean Site engineering test was conducted to prove the field application of the techniques before moving the contaminated site in FY 92

  5. Therapeutic dilemma in fungal keratitis: administration of steroids for immune rejection early after keratoplasty.

    Science.gov (United States)

    Wang, Ting; Li, Suxia; Gao, Hua; Shi, Weiyun

    2016-08-01

    To investigate the timing and dosage of topical corticosteroid use after keratoplasty for fungal keratitis, and to evaluate the results with regard to anterior segment inflammation, immune rejection, and fungal recurrence. This prospective observational study included a total of 244 patients (244 eyes) who underwent penetrating keratoplasty (PK, 118 patients) or lamellar keratoplasty (LK, 126 patients) for fungal keratitis at the Shandong Eye Hospital between January 2009 and April 2014. Topical administration of steroid eye drops was initiated at 1 week after surgery. Changes in ocular inflammation before and after steroid use, percentages of eyes with fungal recurrence and immune rejection, and the relationship between the timing of local administration of steroids and therapeutic anti-inflammatory effects after keratoplasty were evaluated. The follow-up period was 6 months. Anterior segment inflammation was aggravated within 1 week after surgery, with ocular pain, photophobia, redness, and tearing, but was controlled at 7.51 ± 1.76 days after steroid use. Fungal keratitis recurred in three eyes (1.23 %) at 3 to 5 days after administration of corticosteroids, including two eyes receiving PK and one eye receiving LK. Recurrence was controlled with antifungal medications. Allograft rejection occurred in eight (6.78 %) of 118 patients treated by PK, but did not occur in patients treated by LK. Initiating the use of topical corticosteroids in patients with fungal keratitis 1 week after keratoplasty can aid in rapid control of anterior segment inflammation and reduction of immune rejection, with no increase in the rate of fungal recurrence.

  6. Visual rehabilitation using mini-scleral contact lenses after penetrating keratoplasty

    Directory of Open Access Journals (Sweden)

    Guilherme Andrade do Nascimento Rocha

    Full Text Available ABSTRACT Purpose: To report the visual rehabilitation outcomes and complications of patients fitted with mini-scleral rigid gas-permeable (RGP contact lenses (mini-SCLs after penetrating keratoplasty. Methods: We retrospectively reviewed 27 eyes (21 patients that were fitted with mini-SCLs between October 2013 and December 2014. We analyzed demographic data, previous corneal disorders, visual outcomes, interval from keratoplasty to contact lens fitting, topographic and specular microscope data, fitted contact lens parameters, and complications. The patients were divided into two groups according to the elapsed time since surgery: Group A, grafts with <10 years (n=14 eyes; and Group B, grafts with ≥10 years (n=13 eyes. Results: Lens use was discontinued in four eyes, and microbial keratitis developed in one eye during follow-up. No corneal graft rejection was observed. The mean interval between grafting and initial contact lens fitting was 10.6 ± 7.3 years (range: 1-29 years. The most frequent reason for keratoplasty was keratoconus (22 eyes, 81.4%. The mean contact lens-corrected visual acuity (CLCVA was 0.09 ± 0.12 logMar (range: 0.50-0.00 logMar. The average topographic astigmatism, mean steepest keratometry (Kmax, and average cellularity on specular microscopy were 6.19 ± 3.49 diopters (D, 58.4 ± 7.8 D, and 1,231 ± 723 cells/mm2, respectively. Conclusions: Mini-SCL use allowed successful visual rehabilitation after corneal keratoplasty, particularly in patients who required corrective lenses for low visual acuity and were unable to wear RGP contact lenses. Our results indicate that mini-scleral lenses may be an option for the treatment of corneal irregularities, such as those associated with keratoplasty.

  7. Infectious crystalline keratopathy caused by Cladosporium sp. after penetrating keratoplasty: a case report

    Directory of Open Access Journals (Sweden)

    Stock RA

    2016-08-01

    Full Text Available Ricardo Alexandre Stock,1 Elcio Luiz Bonamigo,2 Emeline Cadore,3 Rafael Allan Oechsler4 1Corneal Transplant Section, Santa Terezinha University Hospital, 2Department of Ophthalmology and Bioethics, 3University of Western Santa Catarina, Joaçaba, 4Cornea Department, Oftalmo Center Blumenau, Blumenau, Santa Catarina, Brazil Background: Infectious crystalline keratopathy is a rare, progressive infection characterized by the insidious progression of branches and crystalline corneal opacities with minimal or no inflammation. This case report describes the evolution of an infectious crystalline keratopathy caused by Cladosporium sp., which developed after tectonic keratoplasty in a patient with a history of ocular trauma.Case presentation: A 40-year-old Brazilian male was the victim of firework-induced trauma to the left eye, which resulted in a corneal laceration that could not be sutured as well as a severe traumatic cataract. The patient underwent penetrating keratoplasty and phacoemulsification. During postoperative follow-up, another therapeutic keratoplasty was required because unresponsive infectious keratitis was observed. The infiltrate’s characteristics were suggestive of infectious crystalline keratopathy; in particular, the infiltrate was insidious and progressive, and grayish-white branches appeared in the anterior corneal stroma. As different therapies were administered, inflammatory reactions ranging from mild to severe were observed. The infection was unresponsive to typical antifungal drugs. This lack of response most likely occurred due to steroid treatment and the diffuse corneal spread of an atypical microorganism, which was subsequently identified in culture as Cladosporium sp. After the second therapeutic keratoplasty, the patient’s eye integrity was successfully reestablished.Conclusion: This study likely provides the first report describing a case of infectious crystalline keratopathy caused by Cladosporium sp. This case

  8. Electronic rumble strip

    Science.gov (United States)

    Stauffer, Donald R.; Lenz, James

    1997-02-01

    Single vehicle run-off-road accidents are responsible for significant numbers of injuries and fatalities, and significant property damage. This fact spurs interest in warning systems to alert drivers that vehicles are drifting towards the edge of the road, and that a run-off road accident is imminent. An early attempt at such a warning system is the use of machined grooves on the shoulder to create a rumble strip. Such a system only provides warning, however, as the vehicle actually leaves the traffic lane. More desirable is a system that warns in anticipation of such departure. Honeywell has under development a magnetic lateral guidance system that couples a sensitive magnetoresistive transducer with a magnetic traffic marking tape being developed by 3M. While this development was initially undertaken for use in automated highways, or for special tasks such as guiding snowplow owners, the system can provide an effective, all-weather warning system to provide alert of impending departure from the roadway. This electronic rumble strip is actually a simpler system than the baseline guidance system, and can monitor both distance from the traffic lane edge and the speed of approach to the edge with a low cost sensor.

  9. Varicose veins as a source of adult human endothelial cells.

    Science.gov (United States)

    Ryan, U S; White, L A

    1985-01-01

    Endothelial cells can be harvested from segments of adult human saphenous vein in a varicose condition removed from patients having single or bilateral vein ligation and stripping. The cells are harvested by scraping with a scalpel, seeded on to gelatin coated or Primaria flasks and are passaged by removal with a rubber policeman. The cells cultured in this manner are maintained in a growth medium that is not supplemented with growth factors. The cells grow with a cobblestone monolayer morphology, possess angiotensin converting enzyme activity and react with antibodies to Factor VIII antigen. The cells fluoresce brightly after reaction with monoclonal antibodies specific for human endothelial cells. Thus, stripped varicose vein segments provide a readily available source of endothelial cells.

  10. Ocular penetration and pharmacokinetics of topical gatifloxacin 0.3% and moxifloxacin 0.5% ophthalmic solutions after keratoplasty.

    Science.gov (United States)

    Holland, Edward J; Lane, Stephen S; Kim, Terry; Raizman, Michael; Dunn, Steven

    2008-04-01

    To compare the corneal and aqueous penetration and pharmacokinetics of gatifloxacin 0.3% and moxifloxacin 0.5% ophthalmic solutions and their effect on corneal reepithelialization after penetrating keratoplasty. In this randomized, open-label, parallel-controlled study, corneal and aqueous penetration and the pharmacokinetic parameters of topically applied gatifloxacin 0.3% and moxifloxacin 0.5% (2 preoperative doses of 1 drop given 5 minutes apart) were estimated by using a sparse sampling method. Corneal and aqueous samples were collected 0.25, 0.5, 1, or 2 hours after the final dose. The concentration was determined by a high-performance liquid chromatography method. Stromal Cmax:MBC50 (maximum drug concentration in serum to 50% minimum bactericidal concentration) ratios for selected ocular pathogens were also assessed. Postoperative corneal reepithelialization at days 1, 3, and 7 was evaluated and compared between groups. The calculated pharmacokinetic parameters were higher with moxifloxacin 0.5% than with gatifloxacin 0.3%. The stromal Cmax was 48.5 versus 15.7 microg/g (P = 0.04), and the stromal AUC0-2 (area under the concentration-time curve from 0 to 2 hours) was 30.9 versus 13.6 mug.h/g (P 0.05), and the endothelial AUC0-2 was 43.9 versus 9.8 microg.h/g (P 0.05), and the aqueous AUC0-2 was 1.2 versus 0.4 microg.h/mL (P < 0.05). Stromal Cmax:MBC50 ratios were higher in the moxifloxacin 0.5% group for each pathogen tested. The corneal reepithelialization rates were comparable between groups. Topical preoperative moxifloxacin 0.5% achieved greater corneal and aqueous penetration than did gatifloxacin 0.3%. The clinical significance of this difference is not known. Postoperative use of these agents had similar effects on corneal reepithelialization.

  11. Modified big-bubble technique compared to manual dissection deep anterior lamellar keratoplasty in the treatment of keratoconus.

    Science.gov (United States)

    Knutsson, Karl Anders; Rama, Paolo; Paganoni, Giorgio

    2015-08-01

    To evaluate the clinical findings and results of manual dissection deep anterior lamellar keratoplasty (DALK) compared to a modified big-bubble DALK technique in eyes affected by keratoconus. Sixty eyes of 60 patients with keratoconus were treated with one of the two surgical techniques manual DALK (n = 30); big-bubble DALK (n = 30). The main outcomes measured were visual acuity, corneal topographic parameters, thickness of residual stroma and endothelial cell density (ECD). Patients were examined postoperatively at 1 month, 6 months, 1 year and 1 month after suture removal. Final best spectacle-corrected visual acuity (BSCVA) measured 1 month after suture removal was 0.11 ± 0.08 LogMAR in the big-bubble group compared to 0.13 ± 0.08 in the manual DALK group (p = 0.227). In patients treated with the big-bubble technique without complications (Descemet's membrane completely bared), the stromal residue was not measureable. Mean stromal residual thickness in the manual DALK group was 30.50 ± 27.60 μm. Data analysis of the manual DALK group demonstrated a significant correlation between BSCVA and residual stromal thickness; lower residual stromal thickness correlated with better BSCVA values (Spearman ρ = 0.509, p = 0.018). Postoperative ECD was similar in both groups at all intervals, with no statistically significant differences. In both groups, ECD loss was only significant during the 1- to 6-month interval (p = 0.001 and p < 0.001 in the big-bubble DALK and manual DALK groups, respectively). Manual DALK provides comparable results to big-bubble DALK. Big-bubble DALK permits faster visual recovery and is a surgical technique, which can be easily converted to manual DALK in cases of unsuccessful 'big-bubble' formation. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  12. Readout of silicon strip detectors

    CERN Document Server

    Dabrowski, W

    2003-01-01

    Various architectural and technological options of readout electronics for silicon strip detectors in vertex and tracking applications are discussed briefly. The ABCD3T ASIC for the readout of silicon strip detectors in the ATLAS semiconductor tracker is presented. The architecture of the chip, some design issues and radiation effects are discussed.

  13. The CMS Silicon Strip Tracker

    CERN Document Server

    Azzurri, P

    2005-01-01

    With over 200 square meters of sensitive Silicon and almost 10 million readout channels, the Silicon Strip Tracker of the CMS experiment at the LHC will be the largest Silicon strip detector ever built. The design, construction and expected performance of the CMS Tracker is reviewed in the following.

  14. Bismuth-based electrochemical stripping analysis

    Science.gov (United States)

    Wang, Joseph

    2004-01-27

    Method and apparatus for trace metal detection and analysis using bismuth-coated electrodes and electrochemical stripping analysis. Both anodic stripping voltammetry and adsorptive stripping analysis may be employed.

  15. STUDY OF THE ANATOMICAL AND VISUAL RESULTS OF THERAPEUTIC PENETRATING KERATOPLASTY

    Directory of Open Access Journals (Sweden)

    Chhaya Ashok Shinde

    2017-03-01

    Full Text Available BACKGROUND Therapeutic penetrating keratoplasty for corneal infections restores anatomical integrity. Improvement in instrumentation and surgical techniques, better postoperative management have improved corneal transplant outcome. Purpose of the study was to know what are the anatomical and visual results after therapeutic keratoplasty and to judge what could be the factors affecting the results. MATERIALS AND METHODS Prospective, non-comparative, observational cohort study was done in 56 patient (56 eyes operated for therapeutic penetrating keratoplasty at tertiary care institute .Patients were reviewed for demographic data, postoperative best-corrected visual acuity, graft clarity, and complications. Pre-operative treatment in bacterial infections included Cefazolin 50 mg/ml and Tobramycin 1.4 % or gentamicin 1.4% half hourly, 1% atropine drops. Fungal infections were treated with Natamycin 5% suspension. Debridement was done. Amphotericin B was used against yeasts. Voriconazole (1% eye drops were given in Aspergillus species. With full aseptic precautions penetrating keratoplasty was carried out. The graft was 0.5 mm larger than the lesion. Keratoplasties were evaluated for (1 Graft clarity at 1 month and 1 year postoperative. (2 Cure of the infectious disease after surgery. (3 Anatomical success rate and visual results. RESULTS At the end of one year clear graft with bacterial keratitis was seen in 23 eyes (74.19% out of 31 eyes. In fungal keratitis clear graft was seen in 10 eyes (45.45% out of 22 eyes. 48.22% patients had vision of FC 1m-6/60 compared to preoperative vision at the end of one year. At the end of one year anatomical integrity was maintained in 53 (94.64% cases and it was lost in 5.36% patients. CONCLUSION Patients who underwent keratoplasty with 7.5 mm graft size had maximum graft clarity at the end of one year. Graft was clear in 36 patients (64.29% out of total 56 patients. At the end of 1 year vision improved to FC 1 mt

  16. CLINICAL OUTCOME OF PENETRATING KERATOPLASTY IN CORNEAL OPACITIES OF DIFFERENT AETIOLOGY- A CLINICAL STUDY

    Directory of Open Access Journals (Sweden)

    Dipak Bhuyan

    2017-01-01

    Full Text Available BACKGROUND Corneal transplantation or grafting is an operation in which abnormal corneal host tissue is replaced by healthy donor cornea. According to the World Health Organization (WHO, corneal diseases are among the major causes of vision loss and blindness in the world today after cataract and glaucoma. The aim of the study is to- 1. Evaluate the different aetiology of corneal opacity including active infective aetiology as indicated for penetrating keratoplasty. 2. Determine the clinical outcome of penetrating keratoplasty in relation to graft survival, graft rejection and peri-operative complications in different aetiology groups. 3. Determine the final visual outcome. MATERIALS AND METHODS Candidates for keratoplasty were selected from- 1. Eye Bank of Regional Institute of Ophthalmology (R.I.O. 2. R.I.O OPD. The study period was from September 2014 to August 2015. 30 cases were taken in the study. Descriptive statistics were applied to analyse the data wherever necessary. RESULTS 34.6±19.73 yrs. (mean±SD was the mean age at which transplants were done in the study. Out of total 30 cases, 13 (43.33% and 17 (56.66% were male and female, respectively. The different indications for penetrating keratoplasty are- Post ulcer corneal opacity in 14 cases (46.66%, posttraumatic corneal opacity 9 cases (30%, pseudophakic bullous keratopathy 4 cases (13.33%, corneal dystrophy in 2 cases (6.66% and non-healing corneal ulcer in 1 case (3.33%. 16 cases (53.33% showed clear graft till the last follow up while 11 (33.33% cases showed partially clear graft resulting in improved visual outcome while 3 cases (10.00% of the grafts were opaque due to graft failure. CONCLUSION The major indications for penetrating keratoplasty in this part of the world are post ulcer and posttraumatic corneal opacity and majority of them are illiterate agricultural workers who failed to get adequate treatment on time. Graft survival rate is high, which can be attributed to the

  17. Range gated strip proximity sensor

    Science.gov (United States)

    McEwan, T.E.

    1996-12-03

    A range gated strip proximity sensor uses one set of sensor electronics and a distributed antenna or strip which extends along the perimeter to be sensed. A micro-power RF transmitter is coupled to the first end of the strip and transmits a sequence of RF pulses on the strip to produce a sensor field along the strip. A receiver is coupled to the second end of the strip, and generates a field reference signal in response to the sequence of pulse on the line combined with received electromagnetic energy from reflections in the field. The sensor signals comprise pulses of radio frequency signals having a duration of less than 10 nanoseconds, and a pulse repetition rate on the order of 1 to 10 MegaHertz or less. The duration of the radio frequency pulses is adjusted to control the range of the sensor. An RF detector feeds a filter capacitor in response to received pulses on the strip line to produce a field reference signal representing the average amplitude of the received pulses. When a received pulse is mixed with a received echo, the mixing causes a fluctuation in the amplitude of the field reference signal, providing a range-limited Doppler type signature of a field disturbance. 6 figs.

  18. AcrySof toric intraocular lens for post-keratoplasty astigmatism

    Directory of Open Access Journals (Sweden)

    Nishant Gupta

    2012-01-01

    Full Text Available We report a 63-year-old male who had undergone left eye optical penetrating keratoplasty for central leucomatous corneal opacity 10 years earlier. The eye had clear donor graft with residual astigmatism of −6.50 diopter cylinder (DC at 30°. The patient underwent clear corneal phacoemulsification with implantation of +6.0 D spherical equivalent AcrySof SN60T9 intraocular lens (IOL. Postoperatively, at 10 months, the patient had distance corrected visual acuity of 20/30 with −2.00 DC at 20°. AcrySof toric IOL offers an effective treatment option for post-keratoplasty high corneal astigmatism in patients with cataract.

  19. Tectonic deep anterior lamellar keratoplasty in impending corneal perforation using cryopreserved cornea.

    Science.gov (United States)

    Jang, Ji Hye; Chang, Sung Dong

    2011-04-01

    We report a case of tectonic corneal transplantation for impending corneal perforation to preserve anatomic integrity using cryopreserved donor tissue. An 82-year-old woman exhibiting impending corneal perforation suffered from moderate ocular pain in the left eye for one week. After abnormal tissues around the impending perforation area were carefully peeled away using a Crescent blade and Vannas scissors, the patient received tectonic deep anterior lamellar keratoplasty using a cryopreserved cornea stored in Optisol GS® solution at -70℃ for four weeks. At six months after surgery, the cornea remained transparent and restored the normal corneal thickness. There were no complications such as corneal haze or scars, graft rejection, recurrent corneal ulcer, and postoperative rise of intraocular pressure. Cryopreserved donor lamellar tissue is an effective substitute in emergency tectonic lamellar keratoplasty, such as impending corneal perforation and severe necrotic corneal keratitis. © 2011 The Korean Ophthalmological Society

  20. Outcomes of Infectious versus Sterile Perforated Corneal Ulcers after Therapeutic Penetrating Keratoplasty in the United States

    Science.gov (United States)

    Rush, Sloan W.

    2016-01-01

    Purpose. To compare the long-term outcomes of infectious versus sterile perforated corneal ulcers after therapeutic penetrating keratoplasty in the United States. Methods. The charts of 45 consecutive eyes that underwent primary therapeutic penetrating keratoplasty for a perforated corneal ulcer at a single center were retrospectively reviewed. The perforated ulcers were classified as infectious or sterile and the underlying demographics, clinical features, and 36-month outcomes were compared among the two groups. Results. Mean follow-up among subjects was 38.6 (±6.9) months. Patients presenting with sterile perforated ulcers were more likely to have a peripheral perforation location (p = 0.0333) and recurrence of the underlying disease condition (p = 0.0321), require adjunctive surgical measures in the immediate postoperative period (p ulcer group. Conclusions. Sterile perforated corneal ulcers have a worse prognosis and may be more frequent than those caused by infectious disease in the United States compared to the developing world. PMID:28070416

  1. Common complications of deep lamellar keratoplasty in the early phase of the learning curve

    Directory of Open Access Journals (Sweden)

    Hosny M

    2011-06-01

    Full Text Available Mohamed HosnyOphthalmology Department, Faculty of Medicine, Cairo University, Cairo, EgyptPurpose: To evaluate and record the common complications that face surgeons when they perform their first few series of deep lamellar keratoplasty and measures to avoid these.Setting: Dar El Oyoun Hospital, Cairo, Egypt.Methods: Retrospective study of the first 40 eyes of 40 patients carried out by two corneal surgeons working in the same center. All patients were planned to undergo a deep anterior lamellar keratoplasty using the big bubble technique. Twelve patients suffered from keratoconus while 28 patients had anterior corneal pathologies. Recorded complications were classified as either intraoperative or postoperative.Results: Perforation of Descemet's membrane was the most common intraoperative complication. It occurred in nine eyes (22.5%: five eyes (12.5% had microperforations while four eyes (10% had macroperforations, three eyes (7.5% had central perforations, and six eyes (15% had peripheral perforations. Other complications included incomplete separation of Descemet's membrane and remnants of peripheral stromal tissue. Postoperative complications included double anterior chamber which occurred in four eyes (10% and Descemet's membrane corrugations. Postoperative astigmatism ranged from 1.25 to 4.5 diopters with a mean of 2.86 diopters in the whole series, but in the six cases with identified residual stroma in the periphery of the host bed, the astigmatism ranged from 2.75 to 4.5 diopters with a mean of 3.62 diopters.Conclusion: Deep lamellar keratoplasty is sensitive to procedural details. Learning the common complications and how to avoid them helps novice surgeons to learn the procedure faster.Keywords: deep lamellar keratoplasty, complications, big bubble technique

  2. ATLAS Strips Upgrade

    CERN Document Server

    Miñano, Mercedes

    2009-01-01

    It is foreseen to increase the luminosity of the LHC at CERN around 2020 by about an order of magnitude (SLHC). The ATLAS experiment will require a new particle tracking system for SLHC operation in order to cope with the increase in background events by about one order of magnitude at the higher luminosity. , an all silicon detector with enhanced radiation hardness is being designed. A massive R&D programme, involving many particles physics groups and several leadings manufacturers of silicon detectors for particle physics, is underway to develop silicon sensors with sufficient radiation hardness. In this framework new sensor materials like p-type silicon and the 3D technology are investigated. In parallel, the SCT commissioning experience has taught us to look into alternative module concepts, in which higher levels of integration are combined with the modularity of the SCT approach. We will report on the status of the R&D projects on radiation hard silicon strip detectors for particle physics, link...

  3. ATLAS Strip Upgrade

    CERN Document Server

    Bernabeu, J; The ATLAS collaboration

    2012-01-01

    A phased upgrade of the Large Hadron Collider (LHC) at CERN is planned. The last upgrade phase (HL-LHC) is currently foreseen in 2022-2023. It aims to increase the integrated luminosity to about ten times the original LHC design luminosity. To cope with the harsh conditions in terms of particle rates and radiation dose expected during HL-LHC operation, the ATLAS collaboration is developing technologies for a complete tracker replacement. This new detector will need to provide extreme radiation hardness and a high granularity, within the tight constraints imposed by the existing detectors and their services. An all-silicon high-granularity tracking detector is proposed. An international R&D collaboration is working on the strip layers for this new tracker. A number of large area prototype planar detectors produced on p-type wafers have been designed and fabricated for use at HL-LHC. These prototype detectors and miniature test detectors have been irradiated to a set of fluences matched to HL-LHC expectatio...

  4. Characterization of galvannealed strip

    International Nuclear Information System (INIS)

    Moreas, G.; Hardy, Y.

    1999-01-01

    With the aim of enhancing coating quality control during galvannealing process, an online microscopic image acquisition sensor has been developed at CRM. In galvannealing process, the ζ phase surface density is a coating quality characteristic, and the on-line microscope, equipped with optics placed at 20 mm from the surface, grabs 250 μm x 190 μm images on which ζ crystals (approximate dimensions: 1 μm x 10 μm) can be clearly identified. On-line, the sensor is mounted in front of a roll where the strip has a stable position. The coating surface to sensor optics distance is continuously measured by an accurate triangulation sensor (1 μm repeatability) and is adjusted in such a way that, due to roll eccentricity, the image is focused at least twice per revolution. When focused, image of moving product is frozen by a short (10 ns) laser light pulse and is grabbed. The obtained image is then processed to extract ζ phase percentage and allows adjustment of process parameters to reach the desired coating characteristics. (author)

  5. Penetrating keratoplasty for perforated corneal ulcers: preservation of iris by corneal debulking.

    Science.gov (United States)

    Vajpayee, Rasik B; Singhvi, Arun; Sharma, Namrata; Sinha, Rajesh

    2006-01-01

    This study was designed to study an alternative technique of lamellar separation of corneal layers for therapeutic keratoplasty in place of an en bloc removal of host corneal button in eyes with perforated corneal ulcers with pseudocornea. Twelve eyes with perforated corneal ulcers with pseudocornea in which therapeutic keratoplasty was planned were included in the study. A new technique was used in which the host corneal tissue was removed in layers by lamellar dissection started peripherally and proceeding centripetally with care taken to prevent perforation at the site of iris incarceration. After injection of viscoelastic into the anterior chamber with a 26-gauge needle entered tangentially, the deeper layer of the cornea was then gently dissected and peeled away from the iris tissue, with care not to avulse the fragile iris and the overlying fibrotic membrane. Adjunctive procedures were performed, and the donor tissue was secured over the host bed. A complete separation of the iris tissue from corneal button and the fibrous membrane was achieved in 9 eyes. In 3 eyes, iris was partly trimmed along with the fibrous membrane, because the membrane was totally adherent to the iris tissue. Eight patients required pupilloplasty. Apart from minimal bleeding, no other complication was encountered. At the end of 3 months, 9 of 12 grafts remained clear. Debulking and layer-by-layer removal of host corneal tissue is effective in preservation of iris while performing therapeutic keratoplasty in eyes with perforated corneal ulcers with pseudocornea.

  6. Outcomes of Infectious versus Sterile Perforated Corneal Ulcers after Therapeutic Penetrating Keratoplasty in the United States

    Directory of Open Access Journals (Sweden)

    Sloan W. Rush

    2016-01-01

    Full Text Available Purpose. To compare the long-term outcomes of infectious versus sterile perforated corneal ulcers after therapeutic penetrating keratoplasty in the United States. Methods. The charts of 45 consecutive eyes that underwent primary therapeutic penetrating keratoplasty for a perforated corneal ulcer at a single center were retrospectively reviewed. The perforated ulcers were classified as infectious or sterile and the underlying demographics, clinical features, and 36-month outcomes were compared among the two groups. Results. Mean follow-up among subjects was 38.6 (±6.9 months. Patients presenting with sterile perforated ulcers were more likely to have a peripheral perforation location (p=0.0333 and recurrence of the underlying disease condition (p=0.0321, require adjunctive surgical measures in the immediate postoperative period (p<0.0001, have reperforation after keratoplasty (p=0.0079, have worse best corrected visual acuity (p=0.0130, develop no light perception vision (p=0.0053, and require enucleation/evisceration (p=0.0252 when compared to the infectious perforated ulcer group. Conclusions. Sterile perforated corneal ulcers have a worse prognosis and may be more frequent than those caused by infectious disease in the United States compared to the developing world.

  7. Sutureless femtosecond anterior lamellar keratoplasty: A 1-year follow-up study

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    Rohit Shetty

    2014-01-01

    Full Text Available Aim: To study the safety and efficacy of sutureless femtosecond anterior lamellar keratoplasty (FALK in patients with corneal stromal opacities. Materials and Methods: Eleven eyes of 11 consecutive patients with corneal stromal opacities involving < 250 μ due to various pathologies were included in the study. Preoperatively, all underwent anterior segment imaging with spectral domain optical coherence tomography (SD-OCT (Bioptigen Inc., Durham, North Carolina, USA to measure the depth of the stromal opacity. All patients underwent FALK, and bandage contact lens was placed for a period of 2 weeks. Postoperatively, uncorrected visual acuity, best corrected visual acuity (BCVA, and SD-OCT evaluation were performed. Results: All patients showed significant improvement in BCVA. The mean postoperative BCVA (in decimals improved from 0.11 ± 0.06 preoperatively to 0.59 ± 0.08. There were no intraoperative or significant postoperative complications that were noticed. Conclusion: FALK is a safe and effective alternative to deep anterior lamellar keratoplasty or penetrating keratoplasty in the treatment of anterior stromal opacities.

  8. Buffers and vegetative filter strips

    Science.gov (United States)

    Matthew J. Helmers; Thomas M. Isenhart; Michael G. Dosskey; Seth M. Dabney

    2008-01-01

    This chapter describes the use of buffers and vegetative filter strips relative to water quality. In particular, we primarily discuss the herbaceous components of the following NRCS Conservation Practice Standards.

  9. [Deep anterior lamellar keratoplasty combined with antiviral therapy in the treatment of severe herpes necrotizing stromal keratitis].

    Science.gov (United States)

    Li, S X; Wang, J T; Jiang, Y; Wang, X; Shi, W Y

    2018-02-11

    Objective: To evaluate the efficacy of modified deep lamellar keratoplasty (DLKP) combined with antiviral medications for severe herpes necrotizing stromal keratitis. Methods: Retrospective case series study. Modified DLKP was performed in combination with antiviral medications in fifty patients (50 eyes) with severe necrotizing stromal keratitis, which was unresponsive to systemic and topical antiviral treatment for 1 week, at Shandong Eye Hospital. Before surgery, the operated eyes were examined using slit-lamp microscopy. The size of corneal ulceration and inflammatory infiltration and the depth of ulceration were observed in all of the patients. Corneal scraping and microbial culture and confocal laser scanning microscopy were used to exclude fungal, bacterial, Acanthamoeba, or other infections, and check the number of corneal endothelial cells. Anterior segment optical coherence tomography was used to examine the depth of infiltration, especially the thickness of the remaining cornea below the deepest ulceration. Antiviral drugs were used topically and systemically to control the infection and inflammation. Postoperatively, both antiviral drugs and low-dose corticosteroids were used. The ocular inflammation, corneal graft status and viral recurrence were monitored intraoperatively and postoperatively. Results: All of the fifty patients showed obvious inflammatory infiltration and stromal ulcers, and the corneal stroma in 23 patients (46%) remained less than 1/5 of the corneal thickness. Nine (18%) of the patients presented with descemetocele. The depth of infiltration ranged from 128 μm to 519 μm [mean, (265±84) μm]. The depth of corneal ulcers was deeper than 2/3 of the corneal thickness in 36 eyes (72%). The endothelial cells were visible in 26 eyes. The density of endothelial cells ranged from 1 275 cells/mm(2) to 2 994 cells/mm(2) [mean, (2 053±507) cells/mm(2)]. No fungal or bacterial infection was detected by corneal scraping. The microbial culture

  10. Comparison the post operative refractive errors in same size corneal transplantation through deep lamellar keratoplasty and penetrating keratoplasty methods after sutures removing in keratoconus patients

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    Hasan Razmjoo

    2016-01-01

    Full Text Available Background: Corneal transplantation is a surgery in which cornea is replaced by a donated one and can be completely penetrating keratoplasty (PK or included a part of cornea deep lamellar keratoplasty (DLK. Although the functional results are limited by some complications, it is considered as one of the most successful surgeries. This study aimed to compare the refractive errors after same size corneal transplantation through DLK and PK methods in keratoconus patients over 20 years. Materials and Methods: This descriptive, analytical study was conducted in Feiz Hospital, Sadra and Persian Clinics of Isfahan in 2013–2014. In this study, 35 patients underwent corneal transplantation by PK and 35 patients by DLK, after removing the sutures, the patients were compared in terms of best corrected visual acuity (BCVA and refractive errors. Data were analyzed using Chi-square and t Student tests by SPSS software. Results: The BCVA mean in DLK and PK groups was 6/10 ± 2/10 and 5/10 ± 2/10, respectively, with no significant difference (P = 0.4. The results showed 9 cases of DLK and 6 cases of PK had normal (8/10 ≤ BCVA visual acuity (25.7% vs. 17.1%, 24 cases of DLK and 27 cases of PK had mild vision impairment (68.6% vs. 77.1% and 2 cases of the DLK group and 2 cases of PK had moderate vision impairment, (5.7% vs. 5.7%, there was no significant difference in “BCVA” (P = 0.83. Conclusions: Both methods were acceptably effective in improving BCVA, but according to previous articles (5,9,10 the DLK method due to fewer complications and less risk of rejection was superior to another method and in the absence of any prohibition this method is recommended.

  11. Optical strip waveguide: an analysis.

    Science.gov (United States)

    Ogusu, K; Kawakami, S; Nishida, S

    1979-03-15

    An analysis of the strip waveguide is presented with special emphasis on reflection and transmission of a wave obliquely incident on the side of a strip. Mode conversion and the contribution of radiation modes are taken into account in the formulation. The numerical results of the mode conversion and attenuation constant of the fundamental leaky mode are presented and compared with the results of other authors. The numerical accuracy of our analysis is also checked by two different procedures. It is found that the radiation modes have considerable effects on the waveguide characteristics.

  12. Long-Term Outcomes of High-Risk Keratoplasty in Patients Receiving Systemic Immunosuppression.

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    Chow, Sing-Pey; Cook, Stuart D; Tole, Derek M

    2015-11-01

    Immunological graft rejection after corneal transplantation remains the leading cause of graft failure. Systemic immunosuppression is used for keratoplasty at a high risk of rejection to improve graft survival. We examined the long-term outcomes of high-risk corneal grafts in patients receiving systemic immunosuppression. Thirty-five corneal transplants with a high risk of rejection were identified from 29 patients within a regional immunosuppression service in the United Kingdom. Definition of keratoplasty at "high risk" of rejection included one or more of the following: a history of ipsilateral graft rejection and/or failure, 2 or more quadrants of stromal vascularization, perforation or ocular inflammation at the time of surgery, presence of atopy, and a large-diameter (≥9 mm) graft. Median follow-up duration was 5 years after transplantation. Graft survival at 5 years in patients receiving systemic immunosuppression was 73.5%. Rejection episodes occurred in 14 grafts (40%); these episodes were reversible in 10 grafts (71%). Indications for transplantation were mostly visual (n = 19; 54%) and tectonic (n = 14; 40%). Eighteen grafts (51%) had 2 or more high-risk characteristics. Most patients (n = 20; 69%) received monotherapy, commonly with tacrolimus (n = 15; 52%) or mycophenolate mofetil (n = 8; 28%). Three patients (10%) experienced severe systemic side effects. Median "day-to-day" logMAR visual acuity was 0.5 in grafts for all indications and 0.2 for visual indications. Systemic immunosuppression in patients with high-risk keratoplasty seems to improve graft survival with a median follow-up duration of 5 years and is tolerated by most patients. Despite rejection episodes occurring in 40% of grafts, these were mostly reversible.

  13. Possible Role of Descemet-Stroma Interface for Descemet's Membrane Detachment after Penetrating Keratoplasty.

    Science.gov (United States)

    Ho, Vivian Wm; Romano, Vito; Steger, Bernhard; Kaye, Stephen B

    2018-01-01

    To report two cases of spontaneous Descemet's membrane detachment (DMD) and dehiscence following penetrating keratoplasty (PK). Spontaneous DMD or Descemet's membrane (DM) dehiscence following PK is a rare occurrence. Here, we describe two cases of such an occurrence following PK arising from the graft-host interface. A possible causative relation between DMD/dehiscence and DM-stromal interface attachment is suggested. DMD and dehiscence after PK can be explained by the peripheral thinning of DM and possible changes to the recently characterized anchoring zone of interwoven collagen fibers and proteoglycans at the Descemet-stroma interface.

  14. Buttock Lifting with Polypropylene Strips.

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    Ballivian Rico, José; Esteche, Atilio; Hanke, Carlos José Ramírez; Ribeiro, Ricardo Cavalcanti

    2016-04-01

    The purpose of this study was to evaluate the results of gluteal suspension with polypropylene strips. Ninety healthy female patients between the ages of 20 and 50 years (mean, 26 years), who wished to remodel their buttocks from December 2004 to February 2013 were studied retrospectively. All 90 patients were treated with 2 strips of polypropylene on each buttock using the following procedures: 27 (30 %) patients were suspended with polypropylene strips; 63 (70 %) patients were treated with tumescent liposuction in the sacral "V", lower back, supragluteal regions, and flanks to improve buttocks contour (aspirated volume of fat from 350 to 800 cc); 16 (18 %) patients underwent fat grafting in the subcutaneous and intramuscular layers (up to 300 cc in each buttock to increase volume); 5 (6 %) patients received implants to increase volume; and 4 (4.4 %) patients underwent removal and relocation of intramuscular gluteal implants to improve esthetics. Over an 8-year period, 90 female patients underwent gluteal suspension surgeries. Good esthetic results without complications were obtained in 75 of 90 (84 %) cases. Complications occurred in 15 of 90 (16.6 %) patients, including strip removal due to postoperative pain in 1 (1.1 %) patient, and seroma in both subgluteal sulci in 3 (3.3 %) patients. The results of this study performed in 90 patients over 8 years showed that the suspension with polypropylene strips performed as a single procedure or in combination with other cosmetic methods helps to enhance and lift ptosed gluteal and paragluteal areas. This journal requires that the authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

  15. Management of intra-Descemet membrane air bubble in big-bubble deep anterior lamellar keratoplasty.

    Science.gov (United States)

    Sharma, Namrata; Swarup, Rishi; Bali, Shveta Jindal; Maharana, Prafulla; Titiyal, Jeewan S; Vajpayee, Rasik B

    2013-09-01

    To report the recognition and management of intra-Descemet membrane air bubble (IDMA) as a complication of big-bubble deep anterior lamellar keratoplasty (DALK). IDMA was present intraoperatively in 8 eyes after DALK. Indications for surgery were healed keratitis (n = 4), macular dystrophy (n = 2), and keratoconus (n = 2). The IDMA was present between the anterior banded layer and posterior nonbanded layer of Descemet membrane (DM). They were slid and displaced toward the peripheral cornea using 27-gauge cannula and punctured taking care that underlying DM was not ruptured. DM was bared in all eyes, and DALK was completed in 7 cases. One patient required conversion to penetrating keratoplasty because of macroperforation. No case had double anterior chamber. Mean follow-up was 13.9 ± 4.1 months. A DM fold was noted in 1 eye. Seven cases had postoperative best-corrected visual acuity of 20/60 or better. Prompt recognition of the IDMA intraoperatively is required, which can be managed successfully.

  16. Two-step LASIK with topography-guided ablation to correct astigmatism after penetrating keratoplasty.

    Science.gov (United States)

    Mularoni, Alessandro; Laffi, Gian Luca; Bassein, Leona; Tassinari, Giorgio

    2006-01-01

    To assess the efficacy, predictability, stability, and safety of a two-step LASIK procedure using topography-guided ablation to correct astigmatism after penetrating keratoplasty. Fifteen eyes of 15 patients underwent a two-step LASIK procedure at the Maggiore Hospital of Bologna, Italy. In the first step, a flap was created using the Hansatome microkeratome. In the second step, topography-guided ablation using the LaserSight LSX was planned with interactive software (CIPTA) once topographical and refractive stabilization had been obtained. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), cylindrical correction, gain of lines of BSCVA, spherical equivalent refraction, and complications were analyzed. Minimum follow-up was 12 months (range: 12 to 30 months). Uncorrected visual acuity improved in all 15 (100%) eyes. At the last postoperative examination, 11 (73%) eyes had UCVA > or = 20/40. Nine (60%) eyes were within 1.0 diopter (D) of the attempted correction. Mean postoperative astigmatism was -1.67 (range: -3.5 to 0; standard deviation: 1.26). Index of success of astigmatic correction was 0.26. No patient lost Snellen lines of BSCVA. Intraoperative complications included two buttonhole flaps, and postoperative complications included one flap retraction. No further laser treatment was needed. The two-step LASIK procedure using topography-guided ablation reduces spherical and cylindrical refractive error due to penetrating keratoplasty. Topography-guided ablation also proved to be effective in correcting irregular astigmatism.

  17. Noncontact laser photothermal keratoplasty. I: Biophysical principles and laser beam delivery system.

    Science.gov (United States)

    Parel, J M; Ren, Q; Simon, G

    1994-01-01

    Thermal shrinkage of stromal collagen is known to produce changes in the corneal curvature. We designed a novel, noncontact laser beam delivery system to perform laser photothermal keratoplasty. The instrument consisted of a pulsed holmium:YAG laser (2.10-micrometer wavelength, 250-microsecond pulse width, 5-hertz repetition rate) coupled via a monofilament fiber to a common slit-lamp microscope equipped with a polyprism, an adjustable mask, and a projection lens. The system projected an 8-spot annular pattern of infrared laser energy on the cornea to achieve a thermal profile within the stroma and to attain controlled, predictable collagen shrinkage. The system produced treatment patterns of 8 to 32 spots of 150 to 600 microns diameter in concentric rings, continuously adjustable between 3 and 7 mm. The versatility of the system in creating different treatment patterns was tested on thermal paper and human cadaver eyes. A uniform beam profile and different treatment patterns for myopia, hyperopia, and astigmatism were obtained. Myopic correction of 6.00 diopters was demonstrated on cadaver eyes. Corneal topography documented corneal flattening (> 6.00 D) with the following treatment parameters: each spot size on the cornea = 300 microns, radiant exposure of each spot = 18.0 J/cm2, number of pulses = 1, diameter of the treatment ring = 3 mm. Noncontact slit-lamp microscope laser delivery system for laser photothermal keratoplasty provides flexible and precise selection of laser treatment parameters. It may improve the efficacy of the procedure.

  18. Big Bubble Deep Anterior Lamellar Keratoplasty for Management of Deep Fungal Keratitis

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    Hua Gao

    2014-01-01

    Full Text Available Objective. To evaluate the therapeutic effect of big bubble deep anterior lamellar keratoplasty (DALK in patients with deep fungal keratitis. Methods. Consecutive patients who had DALK for deep fungal keratitis at Shandong Eye Hospital between July 2011 and December 2012 were included. In all patients, the infiltration depth was more than 4/5ths of the corneal thickness. DALK surgery was performed with bare Descemet membrane (DM using the big bubble technique. Corrected distance visual acuity (CDVA, graft status, and intraoperative and postoperative complications were monitored. Results. Big bubble DALK was performed in 23 patients (23 eyes. Intraoperative perforation of the DM occurred in two eyes (8.7% during stromal dissection. The patients received lamellar keratoplasty with an air bubble injected into the anterior chamber. Double anterior chamber formed in 3 eyes (13.0%. Mean CDVA of the patients without cataract, amblyopia, and fungal recurrence was improved from preoperative HM/20 cm−1.0 (LogMAR to 0.23 ± 0.13 (LogMAR at the last followup (P<0.01. Fungal recurrence was found in two patients (8.7%. Corneal stromal graft rejection was noted in one patient (4.3%. Conclusions. DALK using the big bubble technique seems to be effective and safe in the treatment of deep fungal keratitis unresponsive to medication.

  19. Intracameral air following pneumatic noncontact tonometry in a recently post–perforating keratoplasty patient

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    Vámosi P

    2014-04-01

    Full Text Available Péter VámosiDepartment of Ophthalmology, Péterfy Sándor Hospital, Budapest, Department of Ophthalmology, Medical and Health Science Centre, University of Debrecen, Debrecen, HungaryPurpose: The purpose of this report is to highlight the potential risk of noncontact tonometry after routine uncomplicated penetrating keratoplasty (PK.Case report: After uncomplicated PK for keratoconus, routine noncontact tonometry was performed on the second postoperative day. In spite of the adequately closed wound and the tight suture, temporary wound dehiscence occurred, and two-thirds of the anterior chamber was occupied by air. The running suture remained intact, and the Seidel test was negative. One week postoperatively, the patient’s corrected distance visual acuity was 0.4 (0.4 logMAR, and the air bubble had absorbed.Conclusion: This is the first report to conclude that noncontact tonometry may not be sufficiently safe in the early postoperative period in normal PK cases. To prevent possible wound opening, we suggest the use of other tonometry methods during the first several months after PK.Keywords: wound dehiscence, penetrating keratoplasty

  20. Remote manipulation of posterior lamellar corneal grafts using a magnetic field.

    Science.gov (United States)

    Nahum, Yoav; Barliya, Tilda; Bahar, Irit; Livnat, Tami; Nisgav, Yael; Weinberger, Dov

    2013-06-01

    In posterior lamellar keratoplasty procedures such as Descemet stripping endothelial keratoplasty and Descemet membrane endothelial keratoplasty, the lamellar graft is manipulated directly or by injecting an air bubble. This preliminary study sought to evaluate the feasibility of guiding lamellar corneal grafts by generating a magnetic field. Rabbit and porcine Descemet stripping endothelial keratoplasty and Descemet membrane endothelial keratoplasty grafts were manually produced and immersed in a ferromagnetic solution containing nanomagnetic particles conjugated to streptavidin or in gadoteric acid. For the feasibility study, grafts were transferred to an artificial anterior chamber or plastic test tube and a magnetic field was generated with a handheld NdFeB disc magnet. The presence and the sustainability of graft motion were documented under various conditions. For the semiquantitative study, whole or partial grafts were transferred to a plastic test tube after immersion, and the amount of tissue retraction induced by the remote magnet was graded. The grafts were successfully manipulated in all directions by the magnet, from a distance of up to 7 mm. They remained ferromagnetic more than 24 hours after immersion in the ferromagnetic solutions. The degree of retraction was affected by graft size, immersion time, time from immersion, and immersion solution. Posterior lamellar corneal grafts may be made ferromagnetic and remotely manipulated by creation of a magnetic field. The ferromagnetic properties are adjustable. This technique holds promise in attaching and repositioning grafts during keratoplasty. Further research is needed to assess the possible effects of ferromagnetic solutions on corneal endothelial cells and on lamellar graft clarity.

  1. Diet and Endothelial Function

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    ADA M CUEVAS

    2004-01-01

    Full Text Available Endothelial dysfunction is one of the earliest events in atherogenesis. A consequence of endothelial damage is a lower availability of nitric oxide (NO, the most potent endogenous vasodilator. NO inhibits platelet aggregation, smooth muscle cell proliferation and adhesion of monocytes to endothelial cells. Endothelial dysfunction is present in patients with cardiovascular disease and/or coronary risk factors, such as hypertension, dyslipidemia, diabetes, smoking or hyperhomocysteinemia. At present, soluble markers and high resolution ultrasound of the brachial artery, have provided simple tools for the study of endothelial function and the effects of several interventions. It has been demonstrated that dietary factors may induce significant changes on vascular reactivity. Nutrients, such as fish oil, antioxidants, L-arginine, folic acid and soy protein have shown an improvement in endothelial function that can mediate, at least partially, the cardioprotective effects of these substances. Attention has been focused on dietary patterns in populations with lower prevalence of cardiovascular disease. There is some evidence suggesting that Mediterranean diet characterized by high consumption of vegetables, fish, olive oil and moderate wine consumption may have a positive effect on endothelial function. These results give us evidence on the significant role of diet on endothelial function and its impact on the pathogenesis of atherosclerosis

  2. Collisional stripping of planetary crusts

    Science.gov (United States)

    Carter, Philip J.; Leinhardt, Zoë M.; Elliott, Tim; Stewart, Sarah T.; Walter, Michael J.

    2018-02-01

    Geochemical studies of planetary accretion and evolution have invoked various degrees of collisional erosion to explain differences in bulk composition between planets and chondrites. Here we undertake a full, dynamical evaluation of 'crustal stripping' during accretion and its key geochemical consequences. Crusts are expected to contain a significant fraction of planetary budgets of incompatible elements, which include the major heat producing nuclides. We present smoothed particle hydrodynamics simulations of collisions between differentiated rocky planetesimals and planetary embryos. We find that the crust is preferentially lost relative to the mantle during impacts, and we have developed a scaling law based on these simulations that approximates the mass of crust that remains in the largest remnant. Using this scaling law and a recent set of N-body simulations of terrestrial planet formation, we have estimated the maximum effect of crustal stripping on incompatible element abundances during the accretion of planetary embryos. We find that on average approximately one third of the initial crust is stripped from embryos as they accrete, which leads to a reduction of ∼20% in the budgets of the heat producing elements if the stripped crust does not reaccrete. Erosion of crusts can lead to non-chondritic ratios of incompatible elements, but the magnitude of this effect depends sensitively on the details of the crust-forming melting process on the planetesimals. The Lu/Hf system is fractionated for a wide range of crustal formation scenarios. Using eucrites (the products of planetesimal silicate melting, thought to represent the crust of Vesta) as a guide to the Lu/Hf of planetesimal crust partially lost during accretion, we predict the Earth could evolve to a superchondritic 176Hf/177Hf (3-5 parts per ten thousand) at present day. Such values are in keeping with compositional estimates of the bulk Earth. Stripping of planetary crusts during accretion can lead to

  3. [Confocal microscopy as an early relapse marker after keratoplasty due to Fusarium solani keratitis].

    Science.gov (United States)

    Daas, L; Bischoff-Jung, M; Viestenz, A; Seitz, B; Viestenz, A

    2017-01-01

    In the case of therapy-resistant keratitis an infection with Fusarium solani should be taken into consideration as a rare but very severe eye disease. In the majority of cases Fusarium solani keratitis will result in a protracted clinical course despite aggressive medicinal and surgical interventions. We describe the case of a referred patient after intensive topical, intracameral and systemic antibacterial and antimycotic therapy as well as surgical treatment with emergency keratoplasty à chaud because of Fusarium solani keratitis. The patient presented to our department with persistent discomfort for further therapeutic interventions. Using confocal microscopy we were able to demonstrate the presence of fungal hyphae in the host cornea and the graft, which was important for making further surgical decisions. Furthermore, this emphasizes the role of confocal microscopy as an early relapse marker during the clinical monitoring.

  4. Rupture pressure of the posterior lamella obtained during big-bubble deep anterior lamellar keratoplasty.

    Science.gov (United States)

    McKee, Hamish D; Barua, Ankur; Brahma, Arun K; Jhanji, Vishal; Carley, Fiona M

    2012-11-01

    To investigate the pressure required to rupture the posterior lamella obtained during the presumed Descemet membrane-baring big-bubble technique of deep anterior lamellar keratoplasty (DALK). DALK using the big-bubble technique was carried out on donor corneoscleral discs mounted on an artificial anterior chamber. Once the anterior lamella was removed, the chamber was connected to a mercury manometer. The pressure inside the chamber was increased until rupture occurred or the manometer reached its measurement limit. The deep lamella ruptured at 252 mm Hg in one cornea, at 270 mm Hg in another, and had not ruptured at 300 mm Hg (upper limit of the manometer) in the remaining 18 donor corneas. The posterior lamella of big-bubble DALK probably confers significant structural integrity on the globe.

  5. Pachymetry-guided intrastromal air injection ("pachy-bubble") for deep anterior lamellar keratoplasty.

    Science.gov (United States)

    Ghanem, Ramon C; Ghanem, Marcielle A

    2012-09-01

    To evaluate an innovative technique for intrastromal air injection to achieve deep anterior lamellar keratoplasty (DALK) with bare Descemet membrane (DM). Thirty-four eyes with anterior corneal pathology, including 27 with keratoconus, underwent DALK. After 400 μm trephination with a suction trephine, ultrasound pachymetry was performed 0.8 mm internally from the trephination groove in the 11 to 1 o'clock position. In this area, a 2-mm incision was created, parallel to the groove, with a micrometer diamond knife calibrated to 90% depth of the thinnest measurement. A cannula was inserted through the incision and 0.5 mL of air was injected to dissect the DM from the stroma. After peripheral paracentesis, anterior keratectomy was carried out to bare the DM. A 0.25-mm oversized graft was sutured in place. Overall, 94.1% of eyes achieved DALK. Bare DM was achieved in 30 eyes, and a pre-DM dissection was performed in 2 eyes. Air injection was successful in detaching the DM (achieving the big bubble) in 88.2% of the eyes. In keratoconus eyes, the rate was 88.9%. All cases but one required a single air injection to achieve DM detachment. Microperforations occurred in 5 cases: 3 during manual layer-by-layer dissection after air injection failed to detach the DM, 1 during removal of the residual stroma after big-bubble formation, and 1 during the diamond knife incision. Two cases (5.9%) were converted to penetrating keratoplasty because of macroperforations. The technique was reproducible, safe, and highly effective in promoting DALK with bare DM.

  6. Induction of neoplasia after deep anterior lamellar keratoplasty in a CXL-treated cornea.

    Science.gov (United States)

    Krumeich, Jörg H; Brand-Saberi, Beate; Chankiewitz, Verena; Chankiewitz, Erik; Guthoff, Rudolf

    2014-03-01

    Corneal collagen crosslinking (CXL) with ultraviolet-A energy plus riboflavin has become a ubiquitous treatment in early keratoconus, although its long-term safety is unknown. We describe severe sequelae in a CXL-treated patient after he underwent a standard deep anterior lamellar keratoplasty procedure. In April 2009, a healthy 49-year-old male patient (R.H.) underwent bilateral CXL according to the Dresden protocol for progressive keratoconus stage 3. The best-corrected visual acuity did not improve over 20/100 within a postoperative period of 2 years, and contact lenses were not tolerated. Consequently, a unilateral deep anterior lamellar keratoplasty was performed, to transplant an 8-mm fully epithelialized button onto an 8-mm bed with a bared Descemet membrane (surgeon: J.H.K.). The postoperative healing course was unusually disturbed. Sutures pulled through the recipient tissue, which required suture replacement. Portions of the epithelium sloughed off repeatedly, and bulky regrowth displayed no attachment to the Bowman membrane. Within the first weeks, the transplant became cloudy. Two biopsies were removed from the limbus area and submitted to independent histopathological laboratories, both of which diagnosed the condition as epithelial neoplasia. Pathology tests indicated conjunctival intraepithelial neoplasia, the preliminary stage of invasive squamous cell carcinoma, in the keratocyte-voided bed of the recipient. This case suggests that CXL might hamper the ocular healing process and, combined with subsequent corneal surgery, could potentially initiate neoplasia. Further investigation is warranted to determine the safety of the combination of ultraviolet-A/riboflavin treatment and subsequent corneal tissue transplantation.

  7. Quantification of collagen ultrastructure after penetrating keratoplasty - implications for corneal biomechanics.

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    Craig Boote

    Full Text Available To quantify long-term changes in stromal collagen ultrastructure following penetrating keratoplasty (PK, and evaluate their possible implications for corneal biomechanics.A pair of 16 mm post-mortem corneo-scleral buttons was obtained from a patient receiving bilateral penetrating keratoplasty 12 (left/28 (right years previously. Small-angle x-ray scattering quantified collagen fibril spacing, diameter and spatial order at 0.5 mm or 0.25 mm intervals along linear scans across the graft margin. Corresponding control data was collected from two corneo-scleral buttons with no history of refractive surgery. Wide-angle x-ray scattering quantified collagen fibril orientation at 0.25 mm (horizontal×0.25 mm (vertical intervals across both PK specimens. Quantification of orientation changes in the graft margin were verified by equivalent analysis of data from a 13 year post-operative right PK specimen obtained from a second patient in a previous study, and comparison made with new and published data from normal corneas.Marked changes to normal fibril alignment, in favour of tangentially oriented collagen, were observed around the entire graft margin in all PK specimens. The total number of meridional fibrils in the wound margin was observed to decrease by up to 40%, with the number of tangentially oriented fibrils increasing by up to 46%. As a result, in some locations the number of fibrils aligned parallel to the wound outnumbered those spanning it by up to five times. Localised increases in fibril spacing and diameter, with an accompanying reduction in matrix order, were also evident.Abnormal collagen fibril size and spatial order within the PK graft margin are indicative of incomplete stromal wound remodelling and the long term persistence of fibrotic scar tissue. Lasting changes in collagen fibril orientation in and around PK wounds may alter corneal biomechanics and compromise the integrity of the graft-host interface in the long term.

  8. Scleral contact lenses for visual rehabilitation after penetrating keratoplasty: long term outcomes.

    Science.gov (United States)

    Severinsky, Boris; Behrman, Shmuel; Frucht-Pery, Joseph; Solomon, Abraham

    2014-06-01

    To evaluate the success rate of highly gas permeable scleral contact lenses (SCL) for visual rehabilitation after penetrating keratoplasty (PK), over a period of up to 9 years. A total database of 31 consecutive patient fitted with SCL between January 2004 and December 2009 was retrospectively reviewed. Demographic data, etiology prior to lens fitting, visual outcomes, follow up time and complications were analyzed. All eyes were fitted due to inadequate spectacle-corrected vision after successful penetrating keratoplasty or failure of other contact lens modalities. Out of 31 patients fitted, 28 (33 eyes) continue to wear SCL for periods between 0.5 and 8.8 years. The mean duration of follow-up after contact lens fitting was 5.2 ± 2.2 years. The mean age of corneal graft was 17.6 ± 11.4 years (range 4.3-42), and the mean interval between PK and initial contact lens fitting was 12.2 ± 10.7 years (range 0.7-36.0). The average steepest keratometry of our cohort was 55.0 ± 7.5 diopter (D) and the refractive astigmatism was 8.0 ± 4.4 D. The mean contact lens corrected visual acuity (BCVAcl) was 0.78 ± 0.25 (range 0.3-1.2). Twenty-three (82%) patients achieved a functional vision of 0.5 or more. During the studied period, ten (30.0%) eyes presented at least one graft rejection episode and two eyes (6%) had an episode of microbial keratitis. Corneal transplants of 20 years or more show a higher rate of refits due to ectasia recurrence. Scleral lenses should be considered as lens of choice in eyes with complex corneal geometry, as besides visual rehabilitation, their use may delay or prevent further surgical involvement. Copyright © 2013 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  9. Comparison of synthetic glues and 10-0 nylon in rabbit lamellar keratoplasty.

    Science.gov (United States)

    Cho, Soon Young; Kim, Man Soo; Oh, Su Ja; Chung, Sung Kun

    2013-09-01

    To evaluate changes in mean keratometry and to compare wound repair with corneal lamellar grafts in rabbit eyes using human synthetic tissue adhesives and 10-0 nylon. Corneal grafts were made using a 6.0-mm-diameter trephine and blades in the eyes of 15 New Zealand white rabbits. Human fibrin tissue adhesive (Tisseel) was used in group 1, human fibrin tissue adhesive (Beriplast P) was used in group 2, polyethylene glycol adhesive (Coseal) was used in group 3, and 8 bite sutures with 10-0 nylon were used in group 4 (control) for lamellar keratoplasty. Four bite sutures were made with 10-0 nylon in groups 1, 2, and 3. Slit-lamp microscopy and keratometry were performed at 3 days and 1, 2, and 4 weeks after the surgery. Histopathologic and electromicroscopic examinations were performed 4 weeks after the surgery. No inflammation or corneal toxicity was seen in groups 1 and 2. Histologically, a few inflammatory cells were seen in groups 3 and 4. Groups 1, 2, and 3 showed no statistically significant changes in mean keratometry at 4 weeks postoperatively compared with preoperative mean keratometry (Wilcoxon signed-rank test, P = 0.178, 0.208, and 0.889, respectively). The control group showed significant changes in mean keratometry at 4 weeks postoperatively (Wilcoxon signed-rank test, P = 0.018). Human fibrin tissue adhesives were well tolerated in rabbit eyes, with no apparent corneal toxicity. Polyethylene glycol adhesive showed more inflammation and insufficient wound repair compared with human fibrin tissue adhesives. Therefore, human fibrin tissue adhesives can be used as an alternative to sutures in lamellar keratoplasty.

  10. Dynamic Underground Stripping Demonstration Project

    International Nuclear Information System (INIS)

    Aines, R.; Newmark, R.; McConachie, W.; Rice, D.; Ramirez, A.; Siegel, W.; Buettner, M.; Daily, W.; Krauter, P.; Folsom, E.; Boegel, A.J.; Bishop, D.; udel, K.

    1992-03-01

    LLNL is collaborating with the UC Berkeley College of Engineering to develop and demonstrate a system of thermal remediation and underground imaging techniques for use in rapid cleanup of localized underground spills. Called ''Dynamic Stripping'' to reflect the rapid and controllable nature of the process, it will combine steam injection, direct electrical heating, and tomographic geophysical imaging in a cleanup of the LLNL gasoline spill. In the first 8 months of the project, a Clean Site engineering test was conducted to prove the field application of the techniques before moving to the contaminated site in FY 92

  11. 3D silicon strip detectors

    Energy Technology Data Exchange (ETDEWEB)

    Parzefall, Ulrich [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany)], E-mail: ulrich.parzefall@physik.uni-freiburg.de; Bates, Richard [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Boscardin, Maurizio [FBK-irst, Center for Materials and Microsystems, via Sommarive 18, 38050 Povo di Trento (Italy); Dalla Betta, Gian-Franco [INFN and Universita' di Trento, via Sommarive 14, 38050 Povo di Trento (Italy); Eckert, Simon [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany); Eklund, Lars; Fleta, Celeste [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Jakobs, Karl; Kuehn, Susanne [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany); Lozano, Manuel [Instituto de Microelectronica de Barcelona, IMB-CNM, CSIC, Barcelona (Spain); Pahn, Gregor [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany); Parkes, Chris [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Pellegrini, Giulio [Instituto de Microelectronica de Barcelona, IMB-CNM, CSIC, Barcelona (Spain); Pennicard, David [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Piemonte, Claudio; Ronchin, Sabina [FBK-irst, Center for Materials and Microsystems, via Sommarive 18, 38050 Povo di Trento (Italy); Szumlak, Tomasz [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Zoboli, Andrea [INFN and Universita' di Trento, via Sommarive 14, 38050 Povo di Trento (Italy); Zorzi, Nicola [FBK-irst, Center for Materials and Microsystems, via Sommarive 18, 38050 Povo di Trento (Italy)

    2009-06-01

    While the Large Hadron Collider (LHC) at CERN has started operation in autumn 2008, plans for a luminosity upgrade to the Super-LHC (sLHC) have already been developed for several years. This projected luminosity increase by an order of magnitude gives rise to a challenging radiation environment for tracking detectors at the LHC experiments. Significant improvements in radiation hardness are required with respect to the LHC. Using a strawman layout for the new tracker of the ATLAS experiment as an example, silicon strip detectors (SSDs) with short strips of 2-3 cm length are foreseen to cover the region from 28 to 60 cm distance to the beam. These SSD will be exposed to radiation levels up to 10{sup 15}N{sub eq}/cm{sup 2}, which makes radiation resistance a major concern for the upgraded ATLAS tracker. Several approaches to increasing the radiation hardness of silicon detectors exist. In this article, it is proposed to combine the radiation hard 3D-design originally conceived for pixel-style applications with the benefits of the established planar technology for strip detectors by using SSDs that have regularly spaced doped columns extending into the silicon bulk under the detector strips. The first 3D SSDs to become available for testing were made in the Single Type Column (STC) design, a technological simplification of the original 3D design. With such 3D SSDs, a small number of prototype sLHC detector modules with LHC-speed front-end electronics as used in the semiconductor tracking systems of present LHC experiments were built. Modules were tested before and after irradiation to fluences of 10{sup 15}N{sub eq}/cm{sup 2}. The tests were performed with three systems: a highly focused IR-laser with 5{mu}m spot size to make position-resolved scans of the charge collection efficiency, an Sr{sup 90}{beta}-source set-up to measure the signal levels for a minimum ionizing particle (MIP), and a beam test with 180 GeV pions at CERN. This article gives a brief overview of

  12. Diffraction by a finite strip

    Science.gov (United States)

    Williams, M. H.

    1982-01-01

    A new approach is presented to diffraction problems involving plane strip barriers or slit apertures. These are problems that display the effects of multiple interacting edges. The approach taken here provides exact, compact solutions. The theory is introduced through a series of examples that are, in fact, the 'standard' problems of the subject, diffraction of a plane oblique wave by a slit, for example. In each case, the solutions are found to depend explicitly on a single 'special' function and its Fourier transform. These fundamental functions are described, with the emphasis placed on practical computational methods. The example problems are all couched in the language of acoustics.

  13. Mechanical behaviour of a creased thin strip

    OpenAIRE

    Liu, Jie; Xu, Shanqing; Wen, Guilin; Xie, Yi Min

    2018-01-01

    In this study the mechanical behaviour of a creased thin strip under opposite-sense bending was investigated. It was found that a simple crease, which led to the increase of the second moment of area, could significantly alter the overall mechanical behaviour of a thin strip, for example the peak moment could be increased by 100 times. The crease was treated as a cylindrical segment of a small radius. Parametric studies demonstrated that the geometry of the strip could stron...

  14. Quantifiable Lateral Flow Assay Test Strips

    Science.gov (United States)

    2003-01-01

    As easy to read as a home pregnancy test, three Quantifiable Lateral Flow Assay (QLFA) strips used to test water for E. coli show different results. The brightly glowing control line on the far right of each strip indicates that all three tests ran successfully. But the glowing test line on the middle left and bottom strips reveal their samples were contaminated with E. coli bacteria at two different concentrations. The color intensity correlates with concentration of contamination.

  15. Ammonia stripping of biologically treated liquid manure.

    Science.gov (United States)

    Alitalo, Anni; Kyrö, Aleksis; Aura, Erkki

    2012-01-01

    A prerequisite for efficient ammonia removal in air stripping is that the pH of the liquid to be stripped is sufficiently high. Swine manure pH is usually around 7. At pH 7 (at 20°C), only 0.4% of ammonium is in ammonia form, and it is necessary to raise the pH of swine slurry to achieve efficient ammonia removal. Because manure has a very high buffering capacity, large amounts of chemicals are needed to change the slurry pH. The present study showed that efficient air stripping of manure can be achieved with a small amount of chemicals and without strong bases like NaOH. Slurry was subjected to aerobic biological treatment to raise pH before stripping. This facilitated 8 to 32% ammonia removal without chemical treatment. The slurry was further subjected to repeated cycles of stripping with MgO and Ca(OH)(2) additions after the first and second strippings, respectively, to raise slurry pH in between the stripping cycles. After three consecutive stripping cycles, 59 to 86% of the original ammonium had been removed. It was shown that the reduction in buffer capacity of the slurry was due to ammonia and carbonate removal during the stripping cycles. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  16. Optimizing the Stripping Procedure for LHCb

    CERN Document Server

    Richardson, Rachel

    2017-01-01

    The LHCb experiment faces a major challenge from the large amounts of data received while the LHC is running. The ability to sort this information in a useful manner is important for working groups to perform physics analyses. Both hardware and software triggers are used to decrease the data rate and then the stripping process is used to sort the data into streams and further into stripping lines. This project studies the hundreds of stripping lines to look for overlaps between them in order to make the stripping process more efficient.

  17. Potential profile in a conducting polymer strip

    DEFF Research Database (Denmark)

    Bay, Lasse; West, Keld; Vlachopoulos, Nikolaos

    2002-01-01

    Many conjugated polymers show an appreciable difference in volume between their oxidized and reduced forms. This property can be utilized in soft electrochemically driven actuators, "artificial muscles". Several geometries have been proposed for the conversion of the volume expansion into useful...... mechanical work. In a particularly simple geometry, the length change of polymer strips is exploited. The polymer strips are connected to the driving circuit at the end of the strip that is attached to the support of the device. The other end of the strip is connected to the load. The advantage of this set...

  18. Optical coherence tomography anatomy of the corneal endothelial transplantation wound.

    Science.gov (United States)

    Ferré, Luis Alvarez; Nada, Ossama; Sherknies, Denis; Boisjoly, Hélène; Brunette, Isabelle

    2010-07-01

    The goal of this study was to prospectively assess the deep lamellar endothelial keratoplasty (DLEK) wound anatomy and its evolution during the 12 months after surgery, using optical coherence tomography (OCT). The eyes of 8 patients (1 eye per patient) who consecutively underwent DLEK for Fuchs dystrophy or pseudophakic bullous keratopathy were prospectively studied before and 1, 3, 6, and 12 months after surgery. The Stratus OCT apparatus (Carl Zeiss Meditec, Dublin, CA) was used to acquire central and radial scans perpendicular to the wound at 3-, 6-, 9-, and 12-o'clock positions. The following parameters were analyzed: central total thickness, posterior donor-recipient edges gap, donor-recipient height mismatch, tissue compression, and graft detachment. A posterior gap was observed in 4 of the 8 DLEK eyes. At 12 months, the mean gap contour, depth, and width were 242 +/- 67, 101 +/- 45, and 87 +/- 29 microm, respectively. A step was documented in all DLEK eyes (average step height 108 +/- 24 microm). A micrograft detachment was observed in one case and tissue compression in another. In all corneas, the mean central corneal thickness returned to normal range and almost normal anatomy with time after surgery. OCT was found to be a very useful tool for DLEK corneal wound architecture analysis. It revealed microscopic wound irregularities and allowed their quantitative follow-up with time.

  19. A Technique to Salvage Big-Bubble Deep Anterior Lamellar Keratoplasty after Inadvertent Full-Thickness Trephination

    Directory of Open Access Journals (Sweden)

    Siamak Zarei-Ghanavati

    2011-01-01

    Full Text Available Herein we describe a technique for management of large inadvertent full-thickness trephination during deep anterior lamellar keratoplasty using the big-bubble technique without converting to penetrating keratoplasty. First, the anterior chamber is formed with an ophthalmic viscosurgical device (OVD. Then, the full-thickness wound is secured with one X-type 10-0 nylon suture. A 27-gauge needle is attached to a 2 ml air-filled syringe and inserted into the corneal stroma in the meridian opposite to the site of full-thickness trephination. Air is gently injected to produce a limited area of "big-bubble" detaching Descemet′s membrane (DM from the corneal stroma. The "big bubble" is slowly expanded with injection of OVD. Finally, the recipient stroma is removed, the donor lenticule is placed and the DM tear is secured with one full thickness 10-0 nylon suture.

  20. The 'KATOD-1' strip readout ASIC for cathode strip chamber

    International Nuclear Information System (INIS)

    Golutvin, I.A.; Gorbunov, N.V.; Karzhavin, V.Yu.; Khabarov, V.S.; Movchan, S.A.; Smolin, D.A.; Dvornikov, O.V.; Shumejko, N.M.; Chekhovskij, V.A.

    2001-01-01

    The 'KATOD-1', a 16-channels readout ASIC, has been designed to perform tests of P3 and P4 full-scale prototypes of the cathode strip chamber for the ME1/1 forward muon station of the Compact Muon Solenoid (CMS) experiment. The ASIC channel consists of two charge-sensitive preamplifiers, a three-stage shaper with cancellation, and an output driver. The ASIC is instrumented with control of gain, in the range of (-4.2 : +5.0) mV/fC, and control of output pulse-shape. The equivalent input noise is equal to 2400 e with the slope of 12 e/pF for detector capacity up to 200 pF. The peaking time is 100 ns for the chamber signal. The ASIC has been produced by a microwave Bi-jFET technology

  1. Intraocular pressure measurement after penetrating keratoplasty: minified Goldmann applanation tonometer, pneumatonometer, and Tono-Pen versus manometry.

    Science.gov (United States)

    Ménage, M J; Kaufman, P L; Croft, M A; Landay, S P

    1994-09-01

    The accuracy of intraocular pressure measurement with the minified Goldmann applanation tonometer, the pneumatonometer, and the Tono-Pen tonometer were compared in post-mortem human eyes which had undergone penetrating keratoplasty. Enucleated post-mortem human eyes underwent same sized (7.75 mm) or 0.5 mm oversized (8.25 mm) autologous penetrating keratoplasty. Intraocular pressure was then set and measured manometrically while being determined successively with each tonometer over the range of 0-65 mm Hg. Linear regression analysis comparing tonometric and manometric readings showed: (1) minified Goldmann applanation tonometer-slope 0.985 and 0.944, intercept 1.64 and 2.55 mm Hg, correlation coefficient 0.99 and 0.99 in same sized and oversized grafted eyes respectively; (2) pneumatonometer-slope 1.008 and 0.990, intercept 3.37 and 3.69 mm Hg, correlation coefficient 0.99 and 0.98; (3) Tono-Pen-slope 1.061 and 1.002, intercept 5.01 and 4.06 mm Hg, correlation coefficient 0.97 and 0.98. We concluded that the minified Goldmann applanation tonometer is as accurate or more accurate than the pneumatonometer and the Tono-Pen in post-mortem post-keratoplasty human eyes, and may be an economical, convenient alternative to the latter two instruments in clinical practice.

  2. Femtosecond laser-assisted keratoplasty combined with cataract extraction in a patient with keratoconus and oculocutaneous albinism

    Directory of Open Access Journals (Sweden)

    Dorottya Pásztor

    2016-01-01

    Full Text Available In this study, we present a case of a 58-year-old male patient with oculocutaneous albinism, keratoconus, total cataract, and glaucoma originating from father-daughter incest. He underwent femtosecond laser-assisted keratoplasty with “open-sky” cataract extraction and posterior chamber intraocular lens implantation. One week after surgery his uncorrected visual acuity improved from hand motion to 20/200. Six months later corneal K values were 49.1 D in the flat and 50.0 D in the steep meridian. The graft had a central corneal thickness of 488 µm and was well fitted. The patient's quality of life improved substantially due to the surgery. To the best of our knowledge, this is the first report on the association of albinism with advanced keratoconus, total cataract, and glaucoma. Moreover, no previous report on femtosecond laser-assisted keratoplasty using VisuMax femtosecond laser system with “open-sky” cataract extraction is available in the literature. The VisuMax femtosecond laser-assisted keratoplasty ensures fast patient rehabilitation in such challenging cases.

  3. Femtosecond laser-assisted keratoplasty combined with cataract extraction in a patient with keratoconus and oculocutaneous albinism.

    Science.gov (United States)

    Pásztor, Dorottya; Kolozsvári, Bence Lajos; Losonczy, Gergely; Fodor, Mariann

    2016-03-01

    In this study, we present a case of a 58-year-old male patient with oculocutaneous albinism, keratoconus, total cataract, and glaucoma originating from father-daughter incest. He underwent femtosecond laser-assisted keratoplasty with "open-sky" cataract extraction and posterior chamber intraocular lens implantation. One week after surgery his uncorrected visual acuity improved from hand motion to 20/200. Six months later corneal K values were 49.1 D in the flat and 50.0 D in the steep meridian. The graft had a central corneal thickness of 488 µm and was well fitted. The patient's quality of life improved substantially due to the surgery. To the best of our knowledge, this is the first report on the association of albinism with advanced keratoconus, total cataract, and glaucoma. Moreover, no previous report on femtosecond laser-assisted keratoplasty using VisuMax femtosecond laser system with "open-sky" cataract extraction is available in the literature. The VisuMax femtosecond laser-assisted keratoplasty ensures fast patient rehabilitation in such challenging cases.

  4. New strips of convergence for Dirichlet series

    OpenAIRE

    Defant, Andreas

    2010-01-01

    In this article we study the interplay of the theory of classical Dirichlet series in one complex variable with recent development on monomial expansions of holomorphic functions in infinitely many variables. For a given Dirichlet series we obtain new strips of convergence in the complex plane related to Bohr’s classical strips of uniform but non absolute convergence.

  5. Hardness of approximation for strip packing

    DEFF Research Database (Denmark)

    Adamaszek, Anna Maria; Kociumaka, Tomasz; Pilipczuk, Marcin

    2017-01-01

    Strip packing is a classical packing problem, where the goal is to pack a set of rectangular objects into a strip of a given width, while minimizing the total height of the packing. The problem has multiple applications, for example, in scheduling and stock-cutting, and has been studied extensive...

  6. Mechanical behaviour of a creased thin strip

    Directory of Open Access Journals (Sweden)

    J. Liu

    2018-02-01

    Full Text Available In this study the mechanical behaviour of a creased thin strip under opposite-sense bending was investigated. It was found that a simple crease, which led to the increase of the second moment of area, could significantly alter the overall mechanical behaviour of a thin strip, for example the peak moment could be increased by 100 times. The crease was treated as a cylindrical segment of a small radius. Parametric studies demonstrated that the geometry of the strip could strongly influence its flexural behaviour. We showed that the uniform thickness and the radius of the creased segment had the greatest and the least influence on the mechanical behaviour, respectively. We further revealed that material properties could dramatically affect the overall mechanical behaviour of the creased strip by gradually changing the material from being linear elastic to elastic-perfect plastic. After the formation of the fold, the moment of the two ends of the strip differed considerably when the elasto-plastic materials were used, especially for materials with smaller tangent modulus in the plastic range. The deformation patterns of the thin strips from the finite element simulations were verified by physical models made of thin metal strips. The findings from this study provide useful information for designing origami structures for engineering applications using creased thin strips.

  7. CMS Silicon Strip Tracker Performance

    CERN Document Server

    Agram, Jean-Laurent

    2012-01-01

    The CMS Silicon Strip Tracker (SST), consisting of 9.6 million readout channels from 15148 modules and covering an area of 198 square meters, needs to be precisely calibrated in order to correctly reconstruct the events recorded. Calibration constants are derived from different workflows, from promptly reconstructed events with particles as well as from commissioning events gathered just before the acquisition of physics runs. The performance of the SST has been carefully studied since the beginning of data taking: the noise of the detector, data integrity, signal-over-noise ratio, hit reconstruction efficiency and resolution have been all investigated with time and for different conditions. In this paper we describe the reconstruction strategies, the calibration procedures and the detector performance results from the latest CMS operation.

  8. Ultrasonic examination of JBK-75 strip material

    International Nuclear Information System (INIS)

    Cook, K.V.; Cunningham, R.A. Jr.; Lewis, J.C.; McClung, R.W.

    1982-12-01

    An ultrasonic inspection system was assembled to inspect the JBK-75 stainless steel sheath material (for the Large Coil Project) for the Westinghouse-Airco superconducting magnet program. The mechanical system provided for handling the 180-kg (400-lb) coils of strip material [1.6 mm thick by 78 mm wide by 90 to 120 m long (0.064 by 3.07 in. by 300 to 400 ft)], feeding the strip through the ultrasonic inspection and cleaning stations, and respooling the coils. We inspected 54 coils of strip for both longitudinal and laminar flaws. Simulated flaws were used to calibrate both inspections. Saw-cut notches [0.28 mm deep (0.011 in., about 17% of the strip thickness)] were used to calibrate the longitudinal flaw inspections; 1.59-mm-diam (0.063-in.) flat-bottom holes drilled halfway through a calibration strip were used to calibrate the laminar flaw tests

  9. Microscopia confocal en operados de queratoplastia perforante Confocal microscopy in patients operated from penetrating keratoplasty

    Directory of Open Access Journals (Sweden)

    Zulema Gómez Castillo

    2009-06-01

    Full Text Available La microscopia confocal es un examen exploratorio, práctico y poco invasivo que permite conocer las características microscópicas del tejido corneal después del trasplante, por lo que constituye una herramienta muy útil en el manejo de los pacientes operados de queratoplastia. El presente trabajo tiene como finalidad describir las características del tejido corneal en pacientes operados de este tipo de trasplante, mediante la microscopia confocal in vivo. MÉTODOS: Se realizó un estudio descriptivo, de corte transversal, en 40 ojos de 40 pacientes operados de queratoplastia perforante, en el Servicio de Córnea del Instituto Cubano de Oftalmología "Ramón Pando Ferrer", de marzo de 2006 a marzo de 2007. Se confeccionó una historia clínica oftalmológica y se les realizó a todos el examen de microscopia confocal en el injerto corneal con el microscopio confocal CONFOSCAN 4. RESULTADOS: La queratopatía bullosa pseudofáquica fue la afección más frecuente previa a la cirugía y estuvo presente en el 77,5 % de los pacientes. En el 72,5 % de los intervenidos se encontró una disminución del grosor corneal. El epitelio presentó alteraciones en el 62,5 % de los pacientes. Todos presentaron afectación de la forma y el tamaño celular endotelial. En el 82,5 % de los pacientes se observó ausencia de plexos nerviosos. CONCLUSIONES: La microscopia confocal como nueva ciencia en el campo de la oftalmología, favorece el seguimiento evolutivo de las queratoplastias perforantes y con esto no solo a prevenir la aparición de posibles complicaciones, sino además de garantizar el éxito de la cirugía y la función refractiva de la córnea.Confocal microscopy is a practical, exploratory and less invassive examination that allows finding out the microscopic characteristics of the corneal tissue after transplantation, so it is a very useful tool for the management of patients operated from keratoplasty. The present paper was aimed at describing

  10. Comparison of albuminuria test and urine test strip in Japanese hypertensive patients: AVA-E study.

    Science.gov (United States)

    Tani, Yoshihiro; Nakayama, Masaaki; Terawaki, Hiroyuki; Iseki, Kunitoshi; Watanabe, Tsuyoshi

    2015-11-01

    Albuminuria is thought to reflect generalized endothelial dysfunction. In hypertensive patients, albuminuria is related to the risk for cardiovascular disease (CVD) events. Thus, screening for albuminuria is critical for risk stratification in hypertensive patients. However, the actual state of albuminuria in Japanese patients without diabetes remains unclear due to insurance coverage. The CLINITEK microalb creatinine test® is a urine test paper that can assess albumin excretion corrected for urine creatinine levels in only 60 seconds without any special equipment. The semi-quantitative albuminuria test and urine proteinuria test were performed on 8,181 Japanese hypertensive patients, and the clinical significance of the test was evaluated by comparison with the urine test strip method. Albumin creatinine ratio (ACR) albuminuria test were present in 70.0%, 25.7%, and 4.3%, respectively, of patients with a negative urine protein test strip result. Furthermore, in patients with a negative urine protein test strip result, ACR ≥ 30 mg/g creatinine was independently associated with previous CVD (odds ratio: 1.25, 95% confidence interval: 1.00 - 1.57, p albuminuria. Easy and quick albuminuria test on the CLINITEK MICROALB CREATININE TEST might be useful test to risk stratification of hypertensive patients compared to urine test strip.

  11. Infections and endothelial cells

    NARCIS (Netherlands)

    Keller, Tymen T.; Mairuhu, Albert T. A.; de Kruif, Martijn D.; Klein, Saskia K.; Gerdes, Victor E. A.; ten Cate, Hugo; Brandjes, Dees P. M.; Levi, Marcel; van Gorp, Eric C. M.

    2003-01-01

    Systemic infection by various pathogens interacts with the endothelium and may result in altered coagulation, vasculitis and atherosclerosis. Endothelium plays a role in the initiation and regulation of both coagulation and fibrinolysis. Exposure of endothelial cells may lead to rapid activation of

  12. Prototype Strip Barrel Modules for the ATLAS ITk Strip Detector

    CERN Document Server

    Sawyer, Craig; The ATLAS collaboration

    2017-01-01

    The module design for the Phase II Upgrade of the new ATLAS Inner Tracker (ITk) detector at the LHC employs integrated low mass assembly using single-sided flexible circuits with readout ASICs and a powering circuit incorporating control and monitoring of HV, LV and temperature on the module. Both readout and powering circuits are glued directly onto the silicon sensor surface resulting in a fully integrated, extremely low radiation length module which simultaneously reduces the material requirements of the local support structure by allowing a reduced width stave structure to be employed. Such a module concept has now been fully demonstrated using so-called ABC130 and HCC130 ASICs fabricated in 130nm CMOS technology to readout ATLAS12 n+-in-p silicon strip sensors. Low voltage powering for these demonstrator modules has been realised by utilising a DCDC powerboard based around the CERN FEAST ASIC. This powerboard incorporates an HV multiplexing switch based on a Panasonic GaN transistor. Control and monitori...

  13. Aeroelastic deformation of a perforated strip

    Science.gov (United States)

    Guttag, M.; Karimi, H. H.; Falcón, C.; Reis, P. M.

    2018-01-01

    We perform a combined experimental and numerical investigation into the static deformation of perforated elastic strips under uniform aerodynamic loading at high-Reynolds-number conditions. The static shape of the porous strips, clamped either horizontally or vertically, is quantified as they are deformed by wind loading, induced by a horizontal flow. The experimental profiles are compared to numerical simulations using a reduced model that takes into account the normal drag force on the deformed surface. For both configurations (vertical and horizontal clamping), we compute the drag coefficient of the strip, by fitting the experimental data to the model, and find that it decreases as a function of porosity. Surprisingly, we find that, for every value of porosity, the drag coefficients for the horizontal configuration are larger than those of the vertical configuration. For all data in both configurations, with the exception of the continuous strip clamped vertically, a linear relation is found between the porosity and drag. Making use of this linearity, we can rescale the drag coefficient in a way that it becomes constant as a function of the Cauchy number, which relates the force due to fluid loading on the elastic strip to its bending rigidity, independently of the material properties and porosity of the strip and the flow speed. Our findings on flexible strips are contrasted to previous work on rigid perforated plates. These results highlight some open questions regarding the usage of reduced models to describe the deformation of flexible structures subjected to aerodynamic loading.

  14. Delayed-Onset Post-Keratoplasty Endophthalmitis Caused by Vancomycin-Resistant Enterococcus faecium

    Directory of Open Access Journals (Sweden)

    Julio C. Hernandez-Camarena

    2012-10-01

    Full Text Available Background: Vancomycin-resistant Enterococcus (VRE endophthalmitis after penetrating keratoplasty (PKP is very rare, the management is a challenge due to both the pattern of antibiotic resistance and the aggressive nature of the infectious process. We report the first delayed-onset case of VRE endophthalmitis after PKP. Materials and Methods: Case report of a 51-year-old female with a 7-week history of PKP who arrived at the emergency room with signs and symptoms of endophthalmitis. Initial visual acuity was light perception, and a posterior pole exam was not possible due to the intense vitreous reaction. Mode B ultrasound was used to assess the posterior pole. The patient underwent pars plana vitrectomy and received intravitreous antibiotics. Results: Vitreous stains and cultures were positive for Enterococcus faecium resistant to vancomycin. Donor rim cultures and viral PCR were negative. Treatment was carried out by repeated intravitreal antibiotics and systemic linezolid. Clinical improvement was seen after the second dose of intravitreous antibiotics and systemic linezolid, but visual acuity remained at light perception consistent with the ischemic changes observed in the posterior pole. Conclusion: VRE endophthalmitis might be associated with positive donor rim cultures. Prompt use of systemic linezolid in addition to intravitreous antibiotics is recommendable, but even with prompt treatment, visual prognosis is guarded.

  15. Delayed-Onset Post-Keratoplasty Endophthalmitis Caused by Vancomycin-Resistant Enterococcus faecium

    Science.gov (United States)

    Hernandez-Camarena, Julio C.; Bautista-de Lucio, Victor M.; Navas, Alejandro; Ramirez-Miranda, Arturo; Graue-Hernandez, Enrique O.

    2012-01-01

    Background Vancomycin-resistant Enterococcus (VRE) endophthalmitis after penetrating keratoplasty (PKP) is very rare, the management is a challenge due to both the pattern of antibiotic resistance and the aggressive nature of the infectious process. We report the first delayed-onset case of VRE endophthalmitis after PKP. Materials and Methods Case report of a 51-year-old female with a 7-week history of PKP who arrived at the emergency room with signs and symptoms of endophthalmitis. Initial visual acuity was light perception, and a posterior pole exam was not possible due to the intense vitreous reaction. Mode B ultrasound was used to assess the posterior pole. The patient underwent pars plana vitrectomy and received intravitreous antibiotics. Results Vitreous stains and cultures were positive for Enterococcus faecium resistant to vancomycin. Donor rim cultures and viral PCR were negative. Treatment was carried out by repeated intravitreal antibiotics and systemic linezolid. Clinical improvement was seen after the second dose of intravitreous antibiotics and systemic linezolid, but visual acuity remained at light perception consistent with the ischemic changes observed in the posterior pole. Conclusion VRE endophthalmitis might be associated with positive donor rim cultures. Prompt use of systemic linezolid in addition to intravitreous antibiotics is recommendable, but even with prompt treatment, visual prognosis is guarded. PMID:23185179

  16. Sarnicola air-visco bubble technique in deep anterior lamellar keratoplasty.

    Science.gov (United States)

    Muftuoglu, Orkun; Toro, Patricia; Hogan, R Nick; Bowman, R Wayne; Cavanagh, H Dwight; McCulley, James P; Mootha, V Vinod; Sarnicola, Vicenzo

    2013-04-01

    The purpose of this study was to describe a new modification for big-bubble deep anterior lamellar keratoplasty (DALK) using pneumatic pressure to detach Descemet membrane (DM) via air injection followed by ophthalmic viscoelastic device (OVD) injection. After failure of big-bubble formation after air injection, OVD was injected from a different site other than the previous air injection using a 27-gauge cannula to detach DM, called air-visco bubble (AVB) DALK technique. The technique was used in 7 human corneoscleral rims that were investigated with anterior segment optical coherence tomography and histopathology and in 69 eyes that underwent DALK surgeries. Big-bubble formation was noted in 4 of 7 of the donor corneoscleral rims. The anterior segment optical coherence tomography showed big-bubble formations together with intrastromal OVD accumulation. The histology of the donor corneas showed microdetachments at the DM in the periphery, deep intrastromal separation, and big-bubble formation filled with OVD. One hundred forty-one of 210 eyes (67%) underwent successful DALK with only air injection, and 69 of 210 eyes (33%) underwent AVB technique when a big bubble was not achieved with only air injection. All the corneas showed a clear interface with good wound healing when DM was bared with the AVB DALK technique. Additional OVD injection to detach DM may be useful in cases where air injection fails. Also, creating small DM detachments with air injection may facilitate the formation of a big bubble with further OVD injection.

  17. Lamellar keratoplasty using position-guided surgical needle and M-mode optical coherence tomography

    Science.gov (United States)

    Shin, Sungwon; Bae, Jung Kweon; Ahn, Yujin; Kim, Hyeongeun; Choi, Geonho; Yoo, Young-Sik; Joo, Choun-Ki; Moon, Sucbei; Jung, Woonggyu

    2017-12-01

    Deep anterior lamellar keratoplasty (DALK) is an emerging surgical technique for the restoration of corneal clarity and vision acuity. The big-bubble technique in DALK surgery is the most essential procedure that includes the air injection through a thin syringe needle to separate the dysfunctional region of the cornea. Even though DALK is a well-known transplant method, it is still challenged to manipulate the needle inside the cornea under the surgical microscope, which varies its surgical yield. Here, we introduce the DALK protocol based on the position-guided needle and M-mode optical coherence tomography (OCT). Depth-resolved 26-gage needle was specially designed, fabricated by the stepwise transitional core fiber, and integrated with the swept source OCT system. Since our device is feasible to provide both the position information inside the cornea as well as air injection, it enables the accurate management of bubble formation during DALK. Our results show that real-time feedback of needle end position was intuitionally visualized and fast enough to adjust the location of the needle. Through our research, we realized that position-guided needle combined with M-mode OCT is a very efficient and promising surgical tool, which also to enhance the accuracy and stability of DALK.

  18. Customized photorefractive keratectomy to correct high ametropia after penetrating keratoplasty: A pilot study.

    Science.gov (United States)

    De Rosa, Giuseppe; Boccia, Rosa; Santamaria, Carmine; Fabbozzi, Lorenzo; De Rosa, Luigi; Lanza, Michele

    2015-01-01

    To evaluate preliminarily the safety and efficacy of customized photorefractive keratectomy (PRK) to correct ametropia and irregular astigmatism after penetrating keratoplasty (PK). This pilot study included five eyes of five patients with a mean spherical equivalent of -5.1±1.46D (range from -2.75 to -6.50D). In all cases, ametropia and irregular astigmatism was corrected with topography-guided customized PRK. Ocular examinations with topographic analysis were performed preoperatively as well as at 1, 3 and 6 months after surgery. All eyes gained postoperatively at least three Snellen lines of uncorrected visual acuity. Mean refractive spherical equivalent was 0.62±0.63D (range from -0.25 to -1.75D) at 6 months postoperatively. Our pilot study suggests that customized PRK can be a safe and effective method for treating ametropia and irregular astigmatisms after PK. Future studies with larger samples and longer follow-ups should be performed to confirm these results. Copyright © 2013 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  19. The treatment of acute corneal hydrops by subtotal penetrating keratoplasty. Clinical case

    Directory of Open Access Journals (Sweden)

    I. A. Loskutov

    2014-07-01

    Full Text Available Clinical case of acute hydrops treatment using subtotal penetrating keratoplasty (PK is presented. The diagnosis of acute hydrops was based on clinical and functional evaluations including optical coherent tomography (OCT. A part of diseased cornea was removed and examined under a light microscope. These studies revealed morphological changes in almost all corneal layers. OCT and histology demonstrated that PK was indicated to this patient. Recent literature data on the epidemiology and pathogenesis of acute hydrops are presented. This rare disease results from tears in the Descemet’s membrane that allow aqueous humor to enter the stroma. Current treatment is aimed to suppress corneal inflammation, restore endothelium and Descemet’s membrane integrity and drain stromal cysts to optimize cornea healing. In this case, subtotal PK was performed due to the significant corneal thinning and a high risk of its melting. «Material for corneal graft» (iLab, Moscow, Russia was used as a donor material.

  20. Correction of High Astigmatism after Penetrating Keratoplasty with Toric Multifocal Intraocular Lens Implantation

    Directory of Open Access Journals (Sweden)

    Raffaele Nuzzi

    2017-07-01

    Full Text Available After penetrating keratoplasty (PK, high astigmatism is often induced, being frequently about 4–6 dpt. According to the entity and typology of astigmatism, different methods of correction can be used. Selective suture removal, relaxing incisions, wedge resections, compression sutures, photorefractive keratectomy, and laser-assisted in situ keratomileusis can reduce corneal astigmatism and ametropia, but meanwhile they can cause a reduction in the corneal integrity and cause an over- or undercorrection. In case of moderate-to-high regular astigmatisms, the authors propose a toric multifocal intraocular lens (IOL implantation to preserve the corneal integrity (especially in PK after herpetic corneal leukoma keratitis. We evaluated a 45-year-old patient who at the age of 30 was subjected to PK in his left eye due to corneal leukoma herpetic keratitis, which led to high astigmatism (7.50 dpt cyl. 5°. The patient was subjected to phacoemulsification and customized toric multifocal IOL implantation in his left eye. The correction of PK-induced residual astigmatism with a toric IOL implantation is an excellent choice but has to be evaluated in relation to patient age, corneal integrity, longevity graft, and surgical risk. It seems to be a well-tolerated therapeutic choice and with good results.

  1. Pre-banking microbial contamination of donor conjunctiva and storage medium for penetrating keratoplasty.

    Science.gov (United States)

    Inomata, Takenori; Ono, Koichi; Matsuba, Tsuyoshi; Shiang, Tina; Di Zazzo, Antonio; Nakatani, Satoru; Yamaguchi, Masahiro; Ebihara, Nobuyuki; Murakami, Akira

    2017-09-01

    The aims of this study were to investigate the incidence of positive donor tissue cultures before transfer to preservation medium (Optisol™-GS) for penetrating keratoplasty, to verify the efficacy of antibiotics contained in Optisol™-GS by examining the drug susceptibility and to assess the relationship between the results of our microbial assessments as well as donor factors and the incidence of contamination. We conducted a retrospective, cross-sectional study using Juntendo Eye Bank records for all corneal transplantations. Two hundred donor conjunctiva harvestings and storage medium (EP-II ® ) cultures were performed between July 2008 and June 2011. We analyzed the associations between donor factors (age, gender, history of cataract surgery, death-to-preservation interval, cause of death) and contamination rates using multivariate analysis by the generalized estimating equation model. We obtained positive bacterial cultures from 154 of the 200 eyes (77.0%). The isolated bacteria were indigenous, such as coagulase-negative Staphylococci, Corynebacterium sp., and methicillin-resistant Staphylococcus aureus (MRSA). There was significant resistance to levofloxacin (18 eyes, 9.0%) and gentamicin (12 eyes, 6.0%), and no vancomycin-resistant bacteria were detected. The donor factors did not correlate with the prevalence of bacterial contamination in our criteria. Pre-banking microbial assessment allows for microbial detection, bacterial susceptibility and resistance testing. This is useful for developing preservation mediums containing effective spectrum antibiotic agents for high quality control of corneal banking.

  2. Weighing of risk factors for penetrating keratoplasty graft failure: application of Risk Score System

    Directory of Open Access Journals (Sweden)

    Abdo Karim Tourkmani

    2017-03-01

    Full Text Available AIM: To analyze the relationship between the score obtained in the Risk Score System (RSS proposed by Hicks et al with penetrating keratoplasty (PKP graft failure at 1y postoperatively and among each factor in the RSS with the risk of PKP graft failure using univariate and multivariate analysis. METHODS: The retrospective cohort study had 152 PKPs from 152 patients. Eighteen cases were excluded from our study due to primary failure (10 cases, incomplete medical notes (5 cases and follow-up less than 1y (3 cases. We included 134 PKPs from 134 patients stratified by preoperative risk score. Spearman coefficient was calculated for the relationship between the score obtained and risk of failure at 1y. Univariate and multivariate analysis were calculated for the impact of every single risk factor included in the RSS over graft failure at 1y. RESULTS: Spearman coefficient showed statistically significant correlation between the score in the RSS and graft failure (P0.05 between diagnosis and lens status with graft failure. The relationship between the other risk factors studied and graft failure was significant (P<0.05, although the results for previous grafts and graft failure was unreliable. None of our patients had previous blood transfusion, thus, it had no impact. CONCLUSION: After the application of multivariate analysis techniques, some risk factors do not show the expected impact over graft failure at 1y.

  3. Femtosecond Laser Assisted Deep Anterior Lamellar Keratoplasty Outcomes and Healing Patterns Compared to Manual Technique

    Directory of Open Access Journals (Sweden)

    Jorge L. Alio

    2015-01-01

    Full Text Available The purpose of the study is to report the visual, refractive, and wound healing pattern outcomes of femtosecond assisted deep anterior lamellar keratoplasty (DALK compared to the conventional manual technique. DALK was performed on 50 eyes of 47 advanced keratoconus patients. The patients were divided into two groups, 25 eyes each, depending on whether femtosecond assisted or manual DALK technique was performed for the side cut of the procedure only. Patients were followed up at 1 month, 6 months, and 1 year for visual acuity, clinical refraction, corneal cylinder, date of suture removal, and side cut corneal healing pattern according to new grading classification of the side cut scar (Grade 0 = transparent scar, 1 = faint healing opacity, 2 = evident healing opacity, 3 = significant opacity with some cosmetic imbalance, and 4 = highly significant opacity with very significant cosmetic imbalance. Outcomes are reported at one year. In conclusion, femtosecond assisted and manual DALK show comparable visual and refractive outcomes but femtosecond assisted DALK shows more evident corneal wound healing patterns at the side cut. This observation may indicate that an activated cornea wound healing might allow earlier suture removal when femtosecond technology is used to perform the side cut for DALK.

  4. Late spontaneous resolution of a double anterior chamber post deep anterior lamellar keratoplasty

    Directory of Open Access Journals (Sweden)

    Andrea Passani

    2017-01-01

    Full Text Available A 31-year-old healthy male underwent deep anterior lamellar keratoplasty with big-bubble technique for treatment of keratoconus in his right eye. One week after surgery, he presented with detachment of the endothelium-Descemet complex with formation of a double anterior chamber, despite the apparent absence of an intraoperative Descemet membrane rupture. A subsequent intervention with the intent to relocate the corneal graft button was not effective, because the detachment appeared again one day later. The authors hypothesized that, at the time of the stromal dissection with big bubble technique, a small amount of air penetrated into the anterior chamber, creating a false pathway through the trabecular meshwork. The aqueous humor then penetrated the graft flowing through the false pathway, causing the endothelium-Descemet detachment. The persistence of that pathway, even after the intervention of graft repositioning, caused the failure of the latter procedure and persistence of the double chamber. We decided to wait and observe. The double anterior chamber spontaneously resolved in approximately three months.

  5. A video strip chart program

    International Nuclear Information System (INIS)

    Jones, N.L.

    1994-01-01

    A strip chart recorder has been utilized for trend analysis of the Oak Ridge National Laboratory EN tandem since 1987. At the EN, the author could not afford the nice eight channel thermal pen recorder that was used at the 25 URC. He had to suffice with two channel fiber tip or capillary pen type recorders retrieved from salvage and maintained with parts from other salvaged recorders. After cycling through several machines that eventually became completely unserviceable, a search for a new thermal recorder was begun. As much as he hates to write computer code, he decided to try his hand at getting an old data acquisition unit, that had been retrieved several years ago from salvage, to meet his needs. A BASIC language compiler was used because time was not available to learn a more advanced language. While attempting to increase acquisition and scroll speed on the 6 MHz 80286 that the code was first developed on, it became apparent that scrolling only the first small portion of the screen at high speed and then averaging that region and histogramming the average provided both the speed necessary for capturing fairly short duration events, and a trend record without use of back scrolling and disk storage routines. This turned out to be quite sufficient

  6. The Panda Strip Asic: Pasta

    Science.gov (United States)

    Lai, A.

    2018-01-01

    PASTA is the 64 channel front-end chip, designed in a 110 nm CMOS technology to read out the strip sensors of the Micro Vertex Detector (MVD) of the PANDA experiment. This chip provides high resolution timestamp and deposited charge information by means of the time-over-threshold technique. Its working principle is based on a predecessor, the TOFPET ASIC, that was designed for medical applications. A general restructuring of the architecture was needed, in order to meet the specific requirements imposed by the physics programme of PANDA, especially in terms of radiation tolerance, spatial constraints, and readout in absence of a first level hardware trigger. The first revision of PASTA is currently under evaluation at the Forschungszentrum Jülich, where a data acquisition system dedicated to the MVD prototypes has been developed. This paper describes the main aspect of the chip design, gives an overview of the data acquisition system used for the verification, and shows the first results regarding the performance of PASTA.

  7. Dynamic underground stripping demonstration project

    International Nuclear Information System (INIS)

    Newmark, R.L.

    1992-04-01

    LLNL is collaborating with the UC Berkeley College of Engineering to develop and demonstrate a system of thermal remediation techniques for rapid cleanup of localized underground spills. Called dynamic stripping to reflect the rapid and controllable nature of the process, it will combine steam injection, direct electrical heating, and tomographic geophysical imaging in a cleanup of the LLNL gasoline spill. In the first eight months of the project, a Clean Site engineering test was conducted to prove the field application of the techniques. Tests then began on the contaminated site in FY 1992. This report describes the work at the Clean Site, including design and performance criteria, test results, interpretations, and conclusions. We fielded 'a wide range of new designs and techniques, some successful and some not. In this document, we focus on results and performance, lessons learned, and design and operational changes recommended for work at the contaminated site. Each section focuses on a different aspect of the work and can be considered a self-contained contribution

  8. Prevention of Stripping under Chip Seals

    Science.gov (United States)

    2017-10-01

    Eighteen chip-sealed roadways in eight cities and counties in Minnesota were evaluated both in the field (for condition surveys and density tests) and in the laboratory (for permeability, stripping, tensile-strength ratio, asphalt film thickness, and...

  9. Buffer Strips for Riparian Zone Management

    National Research Council Canada - National Science Library

    1991-01-01

    This study provides a review of technical literature concerning the width of riparian buffer strips needed to protect water quality and maintain other important values provided by riparian ecosystem...

  10. Temperature Profile of the Duracell Test Strip.

    Science.gov (United States)

    Viiri, Jouni; Kettunen, Lasse

    1996-01-01

    Presents the temperature profile of the Duracell Test Strip obtained using a Inframetrics 740 thermal imaging radiometer and ThermaGRAM95 software and compares this to the theoretical profile derived by Clark and Bonicamp. (JRH)

  11. Deuteron stripping reactions using dirac phenomenology

    Science.gov (United States)

    Hawk, E. A.; McNeil, J. A.

    2001-04-01

    In this work deuteron stripping reactions are studied using the distorted wave born approximation employing dirac phenomenological potentials. In 1982 Shepard and Rost performed zero-range dirac phenomenological stripping calculations and found a dramatic reduction in the predicted cross sections when compared with similar nonrelativistic calculations. We extend the earlier work by including full finite range effects as well as the deuteron's internal D-state. Results will be compared with traditional nonrelativistic approaches and experimental data at low energy.

  12. The charge collection in silicon strip detectors

    International Nuclear Information System (INIS)

    Boehringer, T.; Hubbeling, L.; Weilhammer, P.; Kemmer, J.; Koetz, U.; Riebesell, M.; Belau, E.; Klanner, R.; Lutz, G.; Neugebauer, E.; Seebrunner, H.J.; Wylie, A.

    1983-02-01

    The charge collection in silicon detectors has been studied, by measuring the response to high-energy particles of a 20μm pitch strip detector as a function of applied voltage and magnetic field. The results are well described by a simple model. The model is used to predict the spatial resolution of silicon strip detectors and to propose a detector with optimized spatial resolution. (orig.)

  13. Properties isotropy of magnesium alloy strip workpieces

    OpenAIRE

    Р. Кавалла; В. Ю. Бажин

    2016-01-01

    The paper discusses the issue of obtaining high quality cast workpieces of magnesium alloys produced by strip roll-casting. Producing strips of magnesium alloys by combining the processes of casting and rolling when liquid melt is fed continuously to fast rolls is quite promising and economic. In the process of sheet stamping considerable losses of metal occur on festoons formed due to anisotropy of properties of foil workpiece, as defined by the macro- and microstructure and modes of rolling...

  14. 33 CFR 157.128 - Stripping system.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Stripping system. 157.128 Section... Crude Oil Washing (COW) System on Tank Vessels Design, Equipment, and Installation § 157.128 Stripping system. (a) Each tank vessel having a COW system under § 157.10(e), § 157.10a(a)(2), or § 157.10c(b)(2...

  15. Quantitative comparison of 3 enamel-stripping devices in vitro: how precisely can we strip teeth?

    Science.gov (United States)

    Johner, Alexander Marc; Pandis, Nikolaos; Dudic, Alexander; Kiliaridis, Stavros

    2013-04-01

    In this in-vitro study, we aimed to investigate the predictability of the expected amount of stripping using 3 common stripping devices on premolars. One hundred eighty extracted premolars were mounted and aligned in silicone. Tooth mobility was tested with Periotest (Medizintechnik Gulden, Modautal, Germany) (8.3 ± 2.8 units). The selected methods for interproximal enamel reduction were hand-pulled strips (Horico, Hapf Ringleb & Company, Berlin, Germany), oscillating segmental disks (O-drive-OD 30; KaVo Dental, Biberach, Germany), and motor-driven abrasive strips (Orthofile; SDC Switzerland, Lugano-Grancia, Switzerland). With each device, the operator intended to strip 0.1, 0.2, 0.3, or 0.4 mm on the mesial side of 15 teeth. The teeth were scanned before and after stripping with a 3-dimensional laser scanner. Superposition and measurement of stripped enamel on the most mesial point of the tooth were conducted with Viewbox software (dHal Software, Kifissia, Greece). The Wilcoxon signed rank test and the Kruskal-Wallis test were applied; statistical significance was set at alpha ≤ 0.05. Large variations between the intended and the actual amounts of stripped enamel, and between stripping procedures, were observed. Significant differences were found at 0.1 mm of intended stripping (P ≤ 0.05) for the hand-pulled method and at 0.4 mm of intended stripping (P ≤ 0.001 to P = 0.05) for all methods. For all scenarios of enamel reduction, the actual amount of stripping was less than the predetermined and expected amount of stripping. The Kruskal-Wallis analysis showed no significant differences between the 3 methods. There were variations in the stripped amounts of enamel, and the stripping technique did not appear to be a significant predictor of the actual amount of enamel reduction. In most cases, actual stripping was less than the intended amount of enamel reduction. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights

  16. A case of recipient bed melt and wound dehiscence after penetrating keratoplasty and subconjunctival injection of bevacizumab.

    Science.gov (United States)

    Bhasin, Purendra; Gujar, Prateek; Bhasin, Priyamvada

    2012-11-01

    We describe a case of recipient bed melt and wound dehiscence after uneventful penetrating keratoplasty and subconjunctival injection of bevacizumab. Three weeks postoperatively, the patient presented with limbal ischemia, recipient bed melt, and wound dehiscence corresponding to the area of bevacizumab injection. The melt was managed by application of cyanoacrylate glue along with bandage contact lens. Although the graft survived, there was a problem in re-epithelization. This case highlights the need for further studies to elucidate the therapeutic dose, side effects, and correct timing of using bevacizumab with respect to corneal transplant surgery.

  17. Conductive keratoplasty for the treatment of presbyopia: comparative study between post- and non-LASIK eyes

    Directory of Open Access Journals (Sweden)

    Minoru Tomita

    2011-02-01

    Full Text Available Minoru Tomita* Miyuki Watabe* Mitsutoshi Ito Tadahiko TsuruShinagawa LASIK Center, Chiyoda-ku, Tokyo, Japan*Minoru Tomita and Miyuki Watabe contributed equally to this studyPurpose: To evaluate the efficacy and safety of conductive keratoplasty (CK for the treatment of presbyopia and analyze the differences in the effects between post- and non-laser in situ keratomileusis (LASIK eyes. Clinical preoperative factors that could affect the predictability of CK were also analyzed.Methods: The visual and refractive outcomes of CK for the treatment of presbyopia in 14 eyes of 13 post-LASIK patients (post-LASIK group mean age 50.9 ± 3.4 years and those of 25 eyes of 25 non-LASIK patients (non-LASIK group mean age 52.4 ± 4.0 years were studied. The clinical efficacy, safety, stability, and predictability of CK were statistically evaluated.Results: The mean (logarithm of the minimum angle of resolution [logMAR] ± standard deviation [SD] of preoperative uncorrected near visual acuity (UNVA and manifest refraction spherical equivalent (MRSE were 0.64 ± 0.25 diopter (D and 0.35 ± 0.48 D, respectively, in the post-LASIK group, and 0.71 ± 0.20 D and 0.64 ± 0.61 D, respectively, in the non-LASIK group. At 6 months after CK, the mean UNVA and MRSE were 0.07 ± 0.13 D and -1.59 ± 0.86 D, respectively, in the post-LASIK group, and 0.07 ± 0.12 D and -1.06 ± 0.56 D, respectively, in the non-LASIK group. At 1 year after CK, the mean UNVA and MRSE were 0.30 ± 0.17 D and -0.58 ± 0.52 D, respectively, in the post-LASIK group, and 0.28 ± 0.34 D and -1.56 ± 0.62 D, respectively, in the non-LASIK group. There was no significant difference between the two groups in either factor at 6 months postoperative (Student’s t-test, P > 0.05. At 1 year after CK, all the treated eyes maintained corrected distance visual acuity better than -0.08 (logMAR. The mean cylindrical errors were within ±1.00 D in 100% of the post-LASIK and non-LASIK patients. As for the

  18. Comparison of descemet-on versus descemet-off deep anterior lamellar keratoplasty.

    Science.gov (United States)

    Zare, Mohammad; Feizi, Sepehr; Hasani, Hamidreza; Silbert, David

    2013-11-01

    To determine the effect of retained donor Descemet membrane (DMs) on visual outcomes, contrast sensitivity (CS), higher-order aberrations (HOAs), and central graft thickness after deep anterior lamellar keratoplasty (DALK) using the big-bubble technique. In this retrospective comparative study, keratoconic eyes undergoing a DALK using the big-bubble technique were enrolled. A bared DM was achieved in all cases. A donor cornea without (group 1; 48 eyes) or with (group 2; 22 eyes) DM was sutured to the recipient bed. The 2 groups were compared in terms of best spectacle-corrected visual acuity, keratometric astigmatism, refractive error, CS, HOAs, and central graft thickness at least 3 months after complete suture removal. Additionally, the rate of postoperative pseudoanterior chamber formation was compared between the study groups. The mean follow-up duration was 23.2 ± 6.9 months in group 1 and 26.5 ± 6.5 months in group 2 (P = 0.61). The postoperative best spectacle-corrected visual acuity was 0.18 ± 0.08 logMAR and 0.24 ± 0.30 logMAR, respectively (P = 0.36). The 2 groups had comparable postoperative keratometric astigmatism, spherical equivalent refraction, and HOAs. In terms of CS, however, group 1 demonstrated better results at a low spatial frequency. The mean postoperative central graft thickness was greater in group 2 (589.8 ± 34.5 μm) than in group 1 (523.6 ± 63.0 μm; P < 0.001). A pseudoanterior chamber developed in 3 eyes of group 1 and in 2 eyes of group 2 (P = 0.23). All cases were successfully managed by giving an intracameral air injection. DALK performed using the big-bubble technique for keratoconus may give better results in terms of CS if a donor cornea without DM is transplanted.

  19. Corneal Graft Rejection Ten Years after Penetrating Keratoplasty in the Cornea Donor Study

    Science.gov (United States)

    Dunn, Steven P.; Gal, Robin L.; Kollman, Craig; Raghinaru, Dan; Dontchev, Mariya; Blanton, Christopher L.; Holland, Edward J; Lass, Jonathan H.; Kenyon, Kenneth R.; Mannis, Mark J; Mian, Shahzad I.; Rapuano, Christopher J.; Stark, Walter J.; Beck, Roy W.

    2015-01-01

    Purpose To assess the effect of donor and recipient factors on corneal allograft rejection and evaluate whether a rejection event was associated with graft failure. Methods 1,090 subjects undergoing penetrating keratoplasty for a moderate risk condition (principally Fuchs’ dystrophy or pseudophakic corneal edema) were followed for up to 12 years. Associations of baseline recipient and donor factors with the occurrence of a rejection event were assessed in univariate and multivariate proportional hazards models. Results Among 651 eyes with a surviving graft at 5 years, the 10-year graft failure (± 99% CI) rates were 12% ± 4% among eyes with no rejection events in the first 5 years, 17% ± 12% in eyes with at least one probable, but no definite rejection event, and 22% ± 20% in eyes with at least one definite rejection event. The only baseline factor significantly associated with a higher risk of definite graft rejection was a preoperative history of glaucoma, particularly when prior glaucoma surgery had been performed and glaucoma medications were being used at time of transplant (10-year incidence 35% ± 23% compared with 14% ± 4% in eyes with no history of glaucoma/intraocular pressure treatment, p=0.008). Conclusion Those patients who experienced a definite rejection event frequently went on to graft failure raising important questions as to how we might change acute and long-term corneal graft management. Multivariate analysis indicated that the prior use of glaucoma medications and glaucoma filtering surgery was a significant risk factor related to a definite rejection event. PMID:25119961

  20. Noncontact holmium:YAG laser thermal keratoplasty to correct hyperopia: 18-month follow-up.

    Science.gov (United States)

    Kohnen, T; Koch, D D; McDonnell, P J; Menefee, R F; Berry, M J

    1997-01-01

    To assess the safety and efficacy of noncontact holmium:yttrium aluminium garnet laser thermal keratoplasty (Ho:YAG LTK) for correction of low to moderate hyperopia. We performed noncontact Ho:YAG LTK on 1 eye each of 28 patients for correction of hyperopia up to +3.88 dpt. Treatments were conducted with 1 or 2 symmetrical octagonal rings of 8 spots/ring with centerline diameters of 6 mm (1 ring) or 6 and 7 mm (2 rings), 10 pulses of laser light at 5 Hz pulse repetition frequency, variable pulse energy in the range of 208-242 mJ and a nominal spot diameter between 615 and 623 microns. At 18 months after surgery, 20 of 22 (91%) treated patient eyes had improved uncorrected distance visual acuity. The mean change in subjective manifest refraction (spherical equivalent) was -0.52 +/- 0.35 dpt and -1.41 +/- 0.53 dpt for 1- and 2-ring treatment groups, respectively, with good stability in the refractive change after 6 months. The mean induced refractive astigmatism was small (0.30 +/- 0.37 dpt/0.25 +/- 0.29 dpt for 1-/2-ring treatments). None of the eyes lost 2 or more lines of spectacle-corrected distance visual acuity. There were no clinically significant changes in glare and contrast sensitivity. Noncontact LTK treatment of low hyperopia is safe and effective, and it is more stable and less prone to induce astigmatism than previously reported contact mode LTK treatments.

  1. Penetrating keratoplasty in eThekwini Health District 2011–2014

    Directory of Open Access Journals (Sweden)

    Monawwar Khan

    2015-07-01

    Full Text Available Background: Penetrating keratoplasty (PK – corneal transplantation or full-thickness corneal graft remains the primary sight-restoring procedure for corneal blindness. South Africa is experiencing a shortage of donor corneas, resulting in long waiting times for a corneal transplant. A corneal graft protocol has been drawn up in the eThekwini Health District to triage prospective corneal graft recipients. Aim: To describe the clinical and demographic profiles of patients on the elective corneal graft waiting list, the waiting time for PK and the scoring system prioritisation process of corneal graft allocation. Setting: All patients on the elective corneal graft waiting list in the eThekwini Health District. Methods: An observational, descriptive cross-sectional study was conducted for a 3-year period between April 2011 and March 2014. Results: A total of 104 patients were on the elective corneal graft waiting list for PK during the study period. Only 20% (n = 21 of patients received a corneal graft during the 3-year period. Amongst those that received a corneal graft, the median waiting period was 280 days (interquartile range 143–520 days. The majority of patients on the waiting list (67% were younger than 41 years of age. The commonest indication for PK was keratoconus (64%. Patients with higher pro forma scores are more likely to receive a corneal graft when a donor cornea becomes available. Conclusion: With a shortage of donor corneas, very few patients receive a corneal graft. Educational programmes are vital to increase awareness of corneal blindness and the value of corneal donations.

  2. A Novel Tectonic Keratoplasty with Femtosecond Laser Intrastromal Lenticule for Corneal Ulcer and Perforation.

    Science.gov (United States)

    Jiang, Yang; Li, Ying; Liu, Xiao-Wei; Xu, Jing

    2016-08-05

    Small incision refractive lenticule extraction (SMILE) is an effective laser procedure that treats myopia. This research was to describe a novel approach to treat corneal ulcer or perforation using the corneal lenticules obtained from SMILE and to evaluate the safety and effectiveness of tectonic keratoplasty with femtosecond laser intrastromal lenticule (TEKIL). A total of twenty patients (22 eyes) were monitored for at least 6 months and were assessed using slit lamp microscopy, optical coherence tomography, and best-corrected visual acuity (BCVA). Postoperative complications throughout the study period were recorded. Corneal ulcer in 14 patients (16 eyes) and corneal perforation in six patients (6 eyes) were treated with TEKIL. The patients were ten females and ten males, with a mean age of 58.5 ± 16.3 years (range: 16-81 years). In this study, the most causes of corneal ulcer or perforation were immunologic causes (54.5%). After TEKIL procedure, global integrity was achieved in all cases. No immune rejection or perforation was detected. The mean BCVA improved from 0.17 ± 0.20 preoperatively to 0.27 ± 0.25 postoperatively at the final follow-up (t = 2.095, P = 0.052). The postoperative BCVA improved in 12 eyes (54.5%) and maintained in nine eyes (40.9%). Vision function successfully maintained in all eyes (100%). In three cases, corneal ulcers were treated by reoperation of TEKIL at 3 months after the initial surgery for the reason that the residual corneal thickness was corneal ulcer and perforation in the condition of emergency and donor shortage.

  3. Endothelial RIG-I activation impairs endothelial function

    International Nuclear Information System (INIS)

    Asdonk, Tobias; Motz, Inga; Werner, Nikos; Coch, Christoph; Barchet, Winfried; Hartmann, Gunther; Nickenig, Georg; Zimmer, Sebastian

    2012-01-01

    Highlights: ► RIG-I activation impairs endothelial function in vivo. ► RIG-I activation alters HCAEC biology in vitro. ► EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 μg of the RIG-ligand 3pRNA (RNA with triphosphate at the 5′end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

  4. Endothelial RIG-I activation impairs endothelial function

    Energy Technology Data Exchange (ETDEWEB)

    Asdonk, Tobias, E-mail: tobias.asdonk@ukb.uni-bonn.de [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Motz, Inga; Werner, Nikos [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Coch, Christoph; Barchet, Winfried; Hartmann, Gunther [Institute for Clinical Chemistry and Clinical Pharmacology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Nickenig, Georg; Zimmer, Sebastian [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer RIG-I activation impairs endothelial function in vivo. Black-Right-Pointing-Pointer RIG-I activation alters HCAEC biology in vitro. Black-Right-Pointing-Pointer EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 {mu}g of the RIG-ligand 3pRNA (RNA with triphosphate at the 5 Prime end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

  5. Development of floating strip micromegas detectors

    Energy Technology Data Exchange (ETDEWEB)

    Bortfeldt, Jonathan

    2014-04-28

    Micromegas are high-rate capable, high-resolution micro-pattern gaseous detectors. Square meter sized resistive strip Micromegas are foreseen as replacement of the currently used precision tracking detectors in the Small Wheel, which is part of the forward region of the ATLAS muon spectrometer. The replacement is necessary to ensure tracking and triggering performance of the muon spectrometer after the luminosity increase of the Large Hadron Collider beyond its design value of 10{sup 34} cm{sup -2}s{sup -1} around 2020. In this thesis a novel discharge tolerant floating strip Micromegas detector is presented and described. By individually powering copper anode strips, the effects of a discharge are confined to a small region of the detector. This reduces the impact of discharges on the efficiency by three orders of magnitude, compared to a standard Micromegas. The physics of the detector is studied and discussed in detail. Several detectors are developed: A 6.4 x 6.4 cm{sup 2} floating strip Micromegas with exchangeable SMD capacitors and resistors allows for an optimization of the floating strip principle. The discharge behavior is investigated on this device in depth. The microscopic structure of discharges is quantitatively explained by a detailed detector simulation. A 48 x 50 cm{sup 2} floating strip Micromegas is studied in high energy pion beams. Its homogeneity with respect to pulse height, efficiency and spatial resolution is investigated. The good performance in high-rate background environments is demonstrated in cosmic muon tracking measurements with a 6.4 x 6.4 cm{sup 2} floating strip Micromegas under lateral irradiation with 550 kHz 20 MeV proton beams. A floating strip Micromegas doublet with low material budget is developed for ion tracking without limitations from multiple scattering in imaging applications during medical ion therapy. Highly efficient tracking of 20 MeV protons at particle rates of 550 kHz is possible. The reconstruction of the

  6. Properties isotropy of magnesium alloy strip workpieces

    Directory of Open Access Journals (Sweden)

    Р. Кавалла

    2016-12-01

    Full Text Available The paper discusses the issue of obtaining high quality cast workpieces of magnesium alloys produced by strip roll-casting. Producing strips of magnesium alloys by combining the processes of casting and rolling when liquid melt is fed continuously to fast rolls is quite promising and economic. In the process of sheet stamping considerable losses of metal occur on festoons formed due to anisotropy of properties of foil workpiece, as defined by the macro- and microstructure and modes of rolling and annealing. The principal causes of anisotropic mechanical properties of metal strips produced by the combined casting and rolling technique are the character of distribution of intermetallic compounds in the strip, orientation of phases of metal defects and the residual tensions. One of the tasks in increasing the output of fit products during stamping operations consists in minimizing the amount of defects. To lower the level of anisotropy in mechanical properties various ways of treating the melt during casting are suggested. Designing the technology of producing strips of magnesium alloys opens a possibility of using them in automobile industry to manufacture light-weight body elements instead of those made of steel.

  7. Superconducting nano-strip particle detectors

    International Nuclear Information System (INIS)

    Cristiano, R; Ejrnaes, M; Casaburi, A; Zen, N; Ohkubo, M

    2015-01-01

    We review progress in the development and applications of superconducting nano-strip particle detectors. Particle detectors based on superconducting nano-strips stem from the parent devices developed for single photon detection (SSPD) and share with them ultra-fast response times (sub-nanosecond) and the ability to operate at a relatively high temperature (2–5 K) compared with other cryogenic detectors. SSPDs have been used in the detection of electrons, neutral and charged ions, and biological macromolecules; nevertheless, the development of superconducting nano-strip particle detectors has mainly been driven by their use in time-of-flight mass spectrometers (TOF-MSs) where the goal of 100% efficiency at large mass values can be achieved. Special emphasis will be given to this case, reporting on the great progress which has been achieved and which permits us to overcome the limitations of existing mass spectrometers represented by low detection efficiency at large masses and charge/mass ambiguity. Furthermore, such progress could represent a breakthrough in the field. In this review article we will introduce the device concept and detection principle, stressing the peculiarities of the nano-strip particle detector as well as its similarities with photon detectors. The development of parallel strip configuration is introduced and extensively discussed, since it has contributed to the significant progress of TOF-MS applications. (paper)

  8. Area specific stripping factors for AGS. A method for extracting stripping factors from survey data

    International Nuclear Information System (INIS)

    Aage, H.K.; Korsbech, U.

    2006-04-01

    In order to use Airborne Gamma-ray Spectrometry (AGS) for contamination mapping, for source search etc. one must to be able to eliminate the contribution to the spectra from natural radioactivity. This in general is done by a stripping technique. The parameters for performing a stripping have until recently been measured by recording gamma spectra at special calibration sites (pads). This may be cumbersome and the parameters may not be correct when used at low gamma energies for environmental spectra. During 2000-2001 DTU tested with success a new technique for Carborne Gamma-ray Spectrometry (CGS) where the spectra from the surveyed area (or from a similar area) were used for calculating the stripping parameters. It was possible to calculate usable stripping ratios for a number of low energy windows - and weak source signals not detectable by other means were discovered with the ASS technique. In this report it is shown that the ASS technique also works for AGS data, and it has been used for recent Danish AGS tests with point sources. (Check of calibration of AGS parameters.) By using the ASS technique with the Boden data (Barents Rescue) an exercise source was detected that has not been detected by any of the teams during the exercise. The ASS technique therefore seems to be better for search for radiation anomalies than any other method known presently. The experiences also tell that although the stripping can be performed correctly at any altitude there is a variation of the stripping parameters with altitude that has not yet been quite understood. However, even with the oddly variations the stripping worked as expected. It was also observed that one might calculate a single common set of usable stripping factors for all altitudes from the entire data set i.e. some average a, b and c values. When those stripping factors were used the stripping technique still worked well. (au)

  9. Area specific stripping factors for AGS. A method for extracting stripping factors from survey data

    Energy Technology Data Exchange (ETDEWEB)

    Aage, H.K.; Korsbech, U. [Technical Univ. of Denmark (Denmark)

    2006-04-15

    In order to use Airborne Gamma-ray Spectrometry (AGS) for contamination mapping, for source search etc. one must to be able to eliminate the contribution to the spectra from natural radioactivity. This in general is done by a stripping technique. The parameters for performing a stripping have until recently been measured by recording gamma spectra at special calibration sites (pads). This may be cumbersome and the parameters may not be correct when used at low gamma energies for environmental spectra. During 2000-2001 DTU tested with success a new technique for Carborne Gamma-ray Spectrometry (CGS) where the spectra from the surveyed area (or from a similar area) were used for calculating the stripping parameters. It was possible to calculate usable stripping ratios for a number of low energy windows - and weak source signals not detectable by other means were discovered with the ASS technique. In this report it is shown that the ASS technique also works for AGS data, and it has been used for recent Danish AGS tests with point sources. (Check of calibration of AGS parameters.) By using the ASS technique with the Boden data (Barents Rescue) an exercise source was detected that has not been detected by any of the teams during the exercise. The ASS technique therefore seems to be better for search for radiation anomalies than any other method known presently. The experiences also tell that although the stripping can be performed correctly at any altitude there is a variation of the stripping parameters with altitude that has not yet been quite understood. However, even with the oddly variations the stripping worked as expected. It was also observed that one might calculate a single common set of usable stripping factors for all altitudes from the entire data set i.e. some average a, b and c values. When those stripping factors were used the stripping technique still worked well. (au)

  10. Visual outcomes after deep anterior lamellar keratoplasty using donor corneas without removal of Descemet membrane and endothelium

    Directory of Open Access Journals (Sweden)

    Tatiana Moura Bastos Prazeres

    Full Text Available ABSTRACT Purpose: The optical quality of the interface after deep anterior lamellar keratoplasty (DALK using the big-bubble technique has been shown to be excellent, leading to results comparable to penetrating keratoplasty. However, there is little in the literature with respect to the controversy surrounding the preparation of the donor cornea. The purpose of this study was to evaluate visual acuity (VA in patients with keratoconus who underwent DALK without removal of the donor graft endothelium. Methods: The records of 90 patients who underwent DALK without the removal of the Descemet membrane (DM and endothelium were retrospectively reviewed. Data collected included uncorrected VA (UCVA and spectacle-corrected VA (SCVA at 7, 30, 180 days, and 1 year postoperatively. Contact lens-corrected visual acuity (CLVA was evaluated after 1 year of the procedure. Results: UCVA was significantly better than preoperative values at 7 days (p<0.001, 30 days (p<0.001, 180 days (p<0.001, and 1 year (p<0.001 after surgery. The 1-year postoperative mean SCVA and CLVA also improved when compared with preoperative SCVA (p<0.001 for both. Conclusions: DALK utilizing donor corneas with attached Descemet membrane and endothelium results in satisfactory VA in patients with keratoconus.

  11. [Fungal dacryocystitis with cacosmia after penetrating keratoplasty--taxonomy and identification of pathogenic fungi based on DNA sequence analysis].

    Science.gov (United States)

    Hanada, Kazuomi; Miyokawa, Naoyuki; Sano, Ayako; Igarashi, Sho; Yoshida, Akitoshi

    2012-12-01

    A 76-year-old woman with a history of penetrating keratoplasty had cacosmia associated with dacryocystitis. Two species of yeast-like fungi were isolated from the contents of her lacrimal sac. Each cultured fungus had a unique, distinctive odor. Althogh treated with an oral antifungal agent and washing of the nasolacrimal duct, the cacosmia was not improved. The continuous dacryocystitis with cacosmia was treated by dacryocystectomy. Two yeast-like fungi were again isolated from the contents of the lacrimal sac. Pathological examination confirmed a diagnosis of fungal dacryocystitis based on the fungal hyphae observed on the excised lacrimal sac wall. The cacosmia promptly disappeared. The fungi isolated from the contents of lacrimal sac were identified by DNA sequencing as Wickerhamomyces anamalus (Pichia anomala-Candida pelliculosa) and Galactomyces geotrichum (Geotrichum candidum). The cause of cacosmia in the present case was fungal dacryocystitis. Antibiotic eye drops and steroid eye drops for the treatment of penetrating keratoplasty can cause atypical fungal presentation in the inconsistently treated lacrimal system and can induce dacryocystitis. Careful usage and consideration is necessary in the long-term use of antibiotics and steroids following corneal transplantation.

  12. In Vitro Endothelialization Test of Biomaterials Using Immortalized Endothelial Cells.

    Directory of Open Access Journals (Sweden)

    Ken Kono

    Full Text Available Functionalizing biomaterials with peptides or polymers that enhance recruitment of endothelial cells (ECs can reduce blood coagulation and thrombosis. To assess endothelialization of materials in vitro, primary ECs are generally used, although the characteristics of these cells vary among the donors and change with time in culture. Recently, primary cell lines immortalized by transduction of simian vacuolating virus 40 large T antigen or human telomerase reverse transcriptase have been developed. To determine whether immortalized ECs can substitute for primary ECs in material testing, we investigated endothelialization on biocompatible polymers using three lots of primary human umbilical vein endothelial cells (HUVEC and immortalized microvascular ECs, TIME-GFP. Attachment to and growth on polymer surfaces were comparable between cell types, but results were more consistent with TIME-GFP. Our findings indicate that TIME-GFP is more suitable for in vitro endothelialization testing of biomaterials.

  13. Pseudomonas aeruginosa endophthalmitis after penetrating keratoplasty transmitted from the same donor to two recipients confirmed by pulsed-field gel electrophoresis.

    Science.gov (United States)

    Oguido, Ana Paula Miyagusko Taba; Casella, Antonio Marcelo Barbante; Hofling-Lima, Ana Luisa; Pacheco, Sergio Arruda; Bispo, Paulo José Martins; Marques, Fernanda

    2011-09-01

    Two devastating cases of multidrug-resistant Pseudomonas aeruginosa endophthalmitis after keratoplasty as the result of transmission from the same donor were confirmed by pulsed-field gel electrophoresis. Strategies for preventing donor-to-host transmission, such as the use of antimicrobial agents of greater efficacy and better methods for detecting microorganisms in preservation medium, could minimize this type of transmission.

  14. Analysis of 'Coma strip' galaxy redshift catalog

    International Nuclear Information System (INIS)

    Klypin, A.A.; Karachentsev, I.D.; Lebedev, V.S.

    1990-01-01

    We present results of the analysis of a galaxy redshift catalog made at the 6-m telescope by Karachentsev and Kopylov (1990. Mon. Not. R. astr. Soc., 243, 390). The catalog covers a long narrow strip on the sky (10 arcmin by 63 0 ) and lists 283 galaxies up to limiting blue magnitude m B = 17.6. The strip goes through the core of Coma cluster and this is called the 'Coma strip' catalog. The catalog is almost two times deeper than the CfA redshift survey and creates the possibility of studying the galaxy distribution on scales of 100-250 Mpc. Due to the small number of galaxies in the catalog, we were able to estimate only very general and stable parameters of the distribution. (author)

  15. Wokker. Notes on a Surrealist comic strip

    Directory of Open Access Journals (Sweden)

    Roger Sabin

    2012-05-01

    Full Text Available This essay explores the creation and development of a British comic strip, Wokker (1971-1999, and its connections with the surrealist movement. Although the strip is remarkable for its content and formalist properties, it remains obscure both because of its publishing circumstances, and because it does not fit easily into a history of comics. Rather it can be argued that its conceptual roots can be traced to the artistic ferment that happened in Paris in the 1920s (with Breton as a key reference point, and that it represents a very English, and late-flowering, example of the surrealist idea.

  16. slice of LEP beamtube with getter strip

    CERN Multimedia

    1989-01-01

    A section of the LEP beam pipe. This is the chamber in which LEP's counter-rotating electron and positron beams travel. It is made of lead-clad aluminium. The beams circulate in the oval cross-section part of the chamber. In the rectangular cross-section part, LEP's innovative getter-strip vacuum pump is installed. After heating to purify the surface of the getter, the strip acts like molecular sticky tape, trapping any stray molecules left behind after the accelerator's traditional vacuum pumps have done their job.

  17. Spray Rolling Aluminum Strip for Transportation Applications

    Energy Technology Data Exchange (ETDEWEB)

    Kevin M. McHugh; Y. Lin; Y. Zhou; E. J. Lavernia; J.-P. Delplanque; S. B. Johnson

    2005-02-01

    Spray rolling is a novel strip casting technology in which molten aluminum alloy is atomized and deposited into the roll gap of mill rolls to produce aluminum strip. A combined experimental/modeling approach has been followed in developing this technology with active participation from industry. The feasibility of this technology has been demonstrated at the laboratory scale and it is currently being scaled-up. This paper provides an overview of the process and compares the microstructure and properties of spray-rolled 2124 aluminum alloy with commercial ingot-processed material

  18. Silicon strip detectors for the LHCb experiment

    OpenAIRE

    Steinkamp, O

    2005-01-01

    The LHCb experiment is a single-arm magnetic spectrometer. Silicon micro-strip detectors are employed in a significant fraction of the tracking system. The Vertex Locator consists of 21 detector stations that operate inside the LHC beam pipe and are separated from the beam vacuum by a thin aluminium foil. The Silicon Tracker is a large-surface silicon micro-strip detector that covers the full acceptance of the experiment in a single tracking station upstream of the spectrometer magnet and the...

  19. CMS Silicon Strip Tracker Operation and Performance

    CERN Document Server

    Boudoul, Gaelle

    2011-01-01

    The Silicon Strip Tracker (SST) of the CMS experiment is, with 9.6 million readout channels, the largest strip tracker ever built. In order to correctly interpret and reconstruct the events recorded it needs to be precisely calibrated, thus ensuring that it fully contributes to the physics research program of the CMS experiment. In 2009 and 2010, the performance of the SST has been carefully studied using cosmic muons and tracks from proton-proton collisions at centre-of-mass energies of 900 GeV, 2.36 TeV and 7 TeV. In this paper, we present some results of the detector performance.

  20. Test strip and method for its use

    International Nuclear Information System (INIS)

    1981-01-01

    A test strip device is described which is useful in performing binding assays involving antigens, antibodies, hormones, vitamins, metabolites or pharmacological agents. The device is capable of application to analytical methods in which a set of sequential test reactions is involved and in which a minute sample size may be used. This test strip is particularly useful in radioimmunoassays. The use of the device is illustrated in radioimmunoassays for 1) thyroxine in serum, 2) the triiodothyronine binding capacity of serum and 3) folic acid and its analogues in serum. (U.K.)

  1. The endothelial border to health

    DEFF Research Database (Denmark)

    Hansen, Nina Wærling; Hansen, Anker Jon; Sams, Anette

    2017-01-01

    by hyperglycemic events because the endothelium transduces “high glucose” signaling into significant pathophysiological phenomena leading to reduced endothelial barrier function, compromised vascular tone regulation and inflammation (e.g., cytokine secretion and RAGE activation). In addition, endothelial...... extracellular proteins form epitopes for potential specific antibody formation upon interactions with reducing sugars. This paper reviews the endothelial metabolism, biology, inflammatory processes, physical barrier functions, and summarizes evidence that although stochastic in nature, endothelial responses...... for several endothelial dysfunctions. There is also mounting epidemiological evidence that dietary intake of refined sugars is important for the development of a number of diseases beyond obesity and type 2 diabetes. Various diseases involving inflammatory and immunological components are accelerated...

  2. [Prolonged topical natamycin 5 % therapy before and after keratoplasty for Fusarium keratitis].

    Science.gov (United States)

    Cvetkova, N; Köstler, J; Prahs, P; Helbig, H; Dietrich-Ntoukas, T

    2016-05-01

    A 69-year-old female patient presented with a therapy-resistant corneal ulcer due to contact lenses, which had been present in the left eye for 1 month. The best corrected visual acuity at the first visit was 0.2. Keratitis with a central corneal ulcer was found. A corneal curettage was performed followed by inpatient therapy with antibiotic eye drops. The first PCR result was negative and the microbiological culture was sterile after 48 h. The clinical findings improved during the hospital stay. There was a decrease in the size of the corneal ulcer and an increase of best corrected visual acuity up to 0.4 so that the patient was discharged. After 8 weeks the patient presented again with a painful eye and visual decline to 0.1. The left eye showed a fulminant keratitis with corneal abscess so that a second course of therapy was initiated. The PCR of the second corneal curettage was positive for Fusarium. Antifungal therapy with natamycin 5 % eye drops (via the international pharmacy) and systemic antifungal therapy with voriconazole (2 × 200 mg) were initiated. Due to personal circumstances the patient rejected corneal transplantation, therefore, local and systemic antifungal outpatient treatment was continued for another 2 months until keratoplasty à chaud of the left eye could be performed. At this time there was a clear reduction of inflammation but a descemetocele developed. The patient was treated with local and systemic antifungal therapy (under control of liver and kindney parameters in blood) for 3 months postoperatively in addition to administration of local and systemic steroids. In cases of therapy-resistant keratitis, a Fusarium keratitis should always be considered. Corneal curettage ahead of therapy is very important. Natamycin 5 % eye drops are the first choice of topical antifungal medication in cases of Fusarium keratitis. Even though intensive local and systemic therapy are performed, patients often require corneal transplantation. Due

  3. Radial and staggered treatment patterns to correct hyperopia using noncontact holmium:YAG laser thermal keratoplasty.

    Science.gov (United States)

    Vinciguerra, P; Kohnen, T; Azzolini, M; Radice, P; Epstein, D; Koch, D D

    1998-01-01

    To compare the effects of two treatment patterns in the correction of hyperopia by noncontact holmium:YAG laser thermal keratoplasty (LTK). Divisione Oculistica, Ospedale S. Gerardo, Monza, Italy. Using two treatment patterns, we performed noncontact LTK in one session in 16 eyes of 8 patients with isometropic hyperopic refractive errors; mean preoperative subjective cycloplegic refraction was +4.90 diopters (D) +/- 1.17 (SD). The treatment consisted of 24 spots in three concentric rings of eight spots each; ring diameters were 6.0, 7.0, and 8.0 mm, respectively. Each spot received seven pulses of laser energy at 30 mJ/pulse. We treated one eye of each patient with a radial pattern (the spots of the three rings aligned on the eight semimeridians) and the fellow eye with a staggered pattern (the spots of the contiguous rings at 22.5 degrees from each other). Follow-up at 1, 15, 30, 90, 180, and 360 days included subjective cycloplegic refraction, uncorrected (UCVA) and spectacle-corrected visual acuity (SCVA), computerized videokeratography (CVK), and Scheimpflug camera examination. One year postoperatively, the mean subjective cycloplegic refraction was +2.75 +/- 1.6 D in the eyes treated with the radial pattern and +3.40 +/- 1.6 D in those treated with the staggered pattern; the mean change in subjective cycloplegic refraction was 2.15 and 1.50 D, respectively. Mean UCVA improved by five lines in the radial group and by four lines in the staggered group. Mean SCVA returned to preoperative levels by day 15 in the radial group and at 1 year in the staggered group; at 1 year, SCVA improved by one line in the radial group and remained unchanged in the staggered group. No eye lost one or more lines of SCVA. Refractive astigmatism was essentially unchanged in both groups. Scheimpflug photography and CVK indicated larger and more uniform corrected zones in the radial group. Radial and staggered patterns effectively corrected low hyperopia, although both were subject to a

  4. KRITIK SOSIAL DALAM KOMIK STRIP PAK BEI

    Directory of Open Access Journals (Sweden)

    Yudhi Novriansyah

    2016-08-01

    Full Text Available This research aimed to do interpret the marking which flange social criticism and know laboring ideology in story of Comic Strip Pak Bei. Research based on theory of structural semiotic according to Ferdinand De Saussure. Using analysis of Syntagmatic as first level of meaning to the text network and also picture, and analysis of Paradigmatic as second level of meaning or implicit meaning (connota-tion, myth, ideology Analysis done to six Comic choice edition of Strip Pak Bei period of November 2004 - Februari 2005 which tend to flange social criticism. At band of syntagmatic, result of research indicate that story theme lifted from social problems that happened in major society. The fact clear progressively when connected by Intertextual with information and texts which have preexisted. At band of Paradigmatic, social criticism tend to emerge dimly, is not transparent. Because of Comic Strip Pak Bei expand in the middle of Java cultural domination that developing myth of criticize as action menacing compatibility and orderliness of society. Story of Comic Strip Pak Bei also confirm dominant ideology in Java society culture, namely ideology of Patriarkhi and Feudalism which still go into effect until now. This prove ideology idea according to Louis Althusser which not again opposition between class, but have been owned and practiced by all social class.

  5. Trees for strip-mined lands

    Science.gov (United States)

    George Hart; William R. Byrnes

    1960-01-01

    Open-pit or strip mining has become an important method of mining bituminous coal in Pennsylvania. In 1958 some 19.5 million tons of soft coal - 29 percent of the total bituminous production in the State - were produced by this method.

  6. Asset Stripping in a Mature Market Economy

    DEFF Research Database (Denmark)

    Klarskov Jeppesen, Kim; Møller, Ulrik Gorm

    2011-01-01

    Purpose – The purpose of this paper is to document a Danish fraud scheme, in which a large number of limited companies were stripped of their assets leaving them with nothing but tax debt, eventually causing the Danish Tax and Customs Administration to lose large sums. Furthermore, the purpose is...... the social supervisory system of a mature market economy. Originality/value – The paper contributes to the knowledge about asset stripping by documenting and analysing the phenomenon in a mature market economy context.......Purpose – The purpose of this paper is to document a Danish fraud scheme, in which a large number of limited companies were stripped of their assets leaving them with nothing but tax debt, eventually causing the Danish Tax and Customs Administration to lose large sums. Furthermore, the purpose...... is to analyse why the asset-stripping schemes occurred in a mature market economy with a strong corporate governance system and a low level of corruption. Design/methodology/approach – The research is conducted as a longitudinal single case study based on documentary research. Findings – The Danish case...

  7. Linear sweep anodic stripping voltammetry: Determination of ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 127; Issue 6. Linear sweep anodic stripping voltammetry: Determination of Chromium (VI) using synthesized gold nanoparticles modified screen-printed electrode. Salamatu Aliyu Tukur Nor Azah Yusof Reza Hajian. Regular Articles Volume 127 Issue 6 June 2015 pp ...

  8. Comic Strips to Accompany Science Museum Exhibits

    Science.gov (United States)

    Chung, Beom Sun; Park, Eun-mi; Kim, Sang-Hee; Cho, Sook-kyoung; Chung, Min Suk

    2016-01-01

    Science museums make the effort to create exhibits with amusing explanations. However, existing explanation signs with lengthy text are not appealing, and as such, visitors do not pay attention to them. In contrast, conspicuous comic strips composed of simple drawings and humors can attract science museum visitors. This study attempted to reveal…

  9. Nanoscale Test Strips for Multiplexed Blood Analysis

    Science.gov (United States)

    Chan, Eugene

    2015-01-01

    A critical component of the DNA Medicine Institute's Reusable Handheld Electrolyte and Lab Technology for Humans (rHEALTH) sensor are nanoscale test strips, or nanostrips, that enable multiplexed blood analysis. Nanostrips are conceptually similar to the standard urinalysis test strip, but the strips are shrunk down a billionfold to the microscale. Each nanostrip can have several sensor pads that fluoresce in response to different targets in a sample. The strips carry identification tags that permit differentiation of a specific panel from hundreds of other nanostrip panels during a single measurement session. In Phase I of the project, the company fabricated, tested, and demonstrated functional parathyroid hormone and vitamin D nanostrips for bone metabolism, and thrombin aptamer and immunoglobulin G antibody nanostrips. In Phase II, numerous nanostrips were developed to address key space flight-based medical needs: assessment of bone metabolism, immune response, cardiac status, liver metabolism, and lipid profiles. This unique approach holds genuine promise for space-based portable biodiagnostics and for point-of-care (POC) health monitoring and diagnostics here on Earth.

  10. Ductility of reinforced concrete columns confined with stapled strips

    International Nuclear Information System (INIS)

    Tahir, M.F.; Khan, Q.U.Z.; Shabbir, F.; Sharif, M.B.; Ijaz, N.

    2015-01-01

    Response of three 150x150x450mm short reinforced concrete (RC) columns confined with different types of confining steel was investigated. Standard stirrups, strips and stapled strips, each having same cross-sectional area, were employed as confining steel around four comer column bars. Experimental work was aimed at probing into the affect of stapled strip confinement on post elastic behavior and ductility level under cyclic axial load. Ductility ratios, strength enhancement factor and core concrete strengths were compared to study the affect of confinement. Results indicate that strength enhancement in RC columns due to strip and stapled strip confinement was not remarkable as compared to stirrup confined column. It was found that as compared to stirrup confined column, stapled strip confinement enhanced the ductility of RC column by 183% and observed axial capacity of stapled strip confined columns was 41 % higher than the strip confined columns. (author)

  11. Laboratory testing of Alcoscan saliva-alcohol test strips

    Science.gov (United States)

    1986-10-01

    This report describes a laboratory evaluation of Alcoscan saliva-alcohol test strips. The objectives of this work were: (1) to determine the precision and accuracy of the Alcoscan strips; and (2) to determine what effect extreme ambient temperatures ...

  12. Imaging of Low Compressibility Strips in the Quantum Hall Liquid

    OpenAIRE

    Finkelstein, G.; Glicofridis, P. I.; Tessmer, S. H.; Ashoori, R. C.; Melloch, M. R.

    1999-01-01

    Using Subsurface Charge Accumulation scanning microscopy we image strips of low compressibility corresponding to several integer Quantum Hall filling factors. We study in detail the strips at Landau level filling factors $\

  13. Dual Strip-Excited Dielectric Resonator Antenna with Parasitic Strips for Radiation Pattern Reconfigurability

    Directory of Open Access Journals (Sweden)

    M. Kamran Saleem

    2014-01-01

    Full Text Available A novel pattern reconfigurable antenna concept utilizing rectangular dielectric resonator antenna (DRA placed over dielectric substrate backed by a ground plane is presented. A dual strip excitation scheme is utilized and both excitation strips are connected together by means of a 50 Ω microstrip feed network placed over the substrate. The four vertical metallic parasitic strips are placed at corner of DRA each having a corresponding ground pad to provide a short/open circuit between the parasitic strip and antenna ground plane, through which a shift of 90° in antenna radiation pattern in elevation plane is achieved. A fractional bandwidth of approximately 40% at center frequency of 1.6 GHz is achieved. The DRA peak realized gain in whole frequency band of operation is found to be above 4 dB. The antenna configuration along with simulation and measured results are presented.

  14. Parallel superconducting strip-line detectors: reset behaviour in the single-strip switch regime

    International Nuclear Information System (INIS)

    Casaburi, A; Heath, R M; Tanner, M G; Hadfield, R H; Cristiano, R; Ejrnaes, M; Nappi, C

    2014-01-01

    Superconducting strip-line detectors (SSLDs) are an important emerging technology for the detection of single molecules in time-of-flight mass spectrometry (TOF-MS). We present an experimental investigation of a SSLD laid out in a parallel configuration, designed to address selected single strip-lines operating in the single-strip switch regime. Fast laser pulses were tightly focused onto the device, allowing controllable nucleation of a resistive region at a specific location and study of the subsequent device response dynamics. We observed that in this regime, although the strip-line returns to the superconducting state after triggering, no effective recovery of the bias current occurs, in qualitative agreement with a phenomenological circuit simulation that we performed. Moreover, from theoretical considerations and by looking at the experimental pulse amplitude distribution histogram, we have the first confirmation of the fact that the phenomenological London model governs the current redistribution in these large area devices also after detection events. (paper)

  15. Parallel superconducting strip-line detectors: reset behaviour in the single-strip switch regime

    Science.gov (United States)

    Casaburi, A.; Heath, R. M.; Tanner, M. G.; Cristiano, R.; Ejrnaes, M.; Nappi, C.; Hadfield, R. H.

    2014-04-01

    Superconducting strip-line detectors (SSLDs) are an important emerging technology for the detection of single molecules in time-of-flight mass spectrometry (TOF-MS). We present an experimental investigation of a SSLD laid out in a parallel configuration, designed to address selected single strip-lines operating in the single-strip switch regime. Fast laser pulses were tightly focused onto the device, allowing controllable nucleation of a resistive region at a specific location and study of the subsequent device response dynamics. We observed that in this regime, although the strip-line returns to the superconducting state after triggering, no effective recovery of the bias current occurs, in qualitative agreement with a phenomenological circuit simulation that we performed. Moreover, from theoretical considerations and by looking at the experimental pulse amplitude distribution histogram, we have the first confirmation of the fact that the phenomenological London model governs the current redistribution in these large area devices also after detection events.

  16. Electrical results of double-sided silicon strip modules for the ATLAS Upgrade Strip Tracker

    CERN Document Server

    Gonzalez-Sevilla, S; The ATLAS collaboration; Cadoux, F; Clark, A; Ferrere, D; Ikegami, Y; Hara, K; La Marra, D; Pelleriti, G; Pohl, M; Takubo, Y; Terada, S; Unno, Y; Weber, M

    2012-01-01

    A double-sided silicon strip module has been designed for the short-strip barrel region of the future ATLAS inner tracker for the High Luminosity LHC. University of Geneva and KEK have produced first module prototypes with common components and similar assembly procedures and jigs. This note reports on the electrical performance of the modules tested. The data acquisition system is described. Results from individual and combined module readout are shown.

  17. Testbeam evaluation of silicon strip modules for ATLAS Phase - II Strip Tracker Upgrade

    CERN Document Server

    Blue, Andrew; The ATLAS collaboration; Ai, Xiaocong; Allport, Phillip; Arling, Jan-Hendrik; Atkin, Ryan Justin; Bruni, Lucrezia Stella; Carli, Ina; Casse, Gianluigi; Chen, Liejian; Chisholm, Andrew; Cormier, Kyle James Read; Cunningham, William Reilly; Dervan, Paul; Diez Cornell, Sergio; Dolezal, Zdenek; Dopke, Jens; Dreyer, Etienne; Dreyling-Eschweiler, Jan Linus Roderik; Escobar, Carlos; Fabiani, Veronica; Fadeyev, Vitaliy; Fernandez Tejero, Javier; Fleta Corral, Maria Celeste; Gallop, Bruce; Garcia-Argos, Carlos; Greenall, Ashley; Gregor, Ingrid-Maria; Greig, Graham George; Guescini, Francesco; Hara, Kazuhiko; Hauser, Marc Manuel; Huang, Yanping; Hunter, Robert Francis Holub; Keller, John; Klein, Christoph; Kodys, Peter; Koffas, Thomas; Kotek, Zdenek; Kroll, Jiri; Kuehn, Susanne; Lee, Steven Juhyung; Liu, Yi; Lohwasser, Kristin; Meszarosova, Lucia; Mikestikova, Marcela; Mi\\~nano Moya, Mercedes; Mori, Riccardo; Moser, Brian; Nikolopoulos, Konstantinos; Peschke, Richard; Pezzullo, Giuseppe; Phillips, Peter William; Poley, Anne-luise; Queitsch-Maitland, Michaela; Ravotti, Federico; Rodriguez Rodriguez, Daniel

    2018-01-01

    The planned HL-LHC (High Luminosity LHC) is being designed to maximise the physics potential of the LHC with 10 years of operation at instantaneous luminosities of \\mbox{$7.5\\times10^{34}\\;\\mathrm{cm}^{-2}\\mathrm{s}^{-1}$}. A consequence of this increased luminosity is the expected radiation damage requiring the tracking detectors to withstand hadron equivalences to over $1x10^{15}$ 1 MeV neutron equivalent per $cm^{2}$ in the ATLAS Strips system. The silicon strip tracker exploits the concept of modularity. Fast readout electronics, deploying 130nm CMOS front-end electronics are glued on top of a silicon sensor to make a module. The radiation hard n-in-p micro-strip sensors used have been developed by the ATLAS ITk Strip Sensor collaboration and produced by Hamamatsu Photonics. A series of tests were performed at the DESY-II test beam facility to investigate the detailed performance of a strip module with both 2.5cm and 5cm length strips before irradiation. The DURANTA telescope was used to obtain a pointing...

  18. Conveyorized Photoresist Stripping Replacement for Flex Circuit Fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Megan Donahue

    2009-02-24

    A replacement conveyorized photoresist stripping system was characterized to replace the ASI photoresist stripping system. This system uses the qualified ADF-25c chemistry for the fabrication of flex circuits, while the ASI uses the qualified potassium hydroxide chemistry. The stripping process removes photoresist, which is used to protect the copper traces being formed during the etch process.

  19. 7 CFR 29.6128 - Straight Stripped (X Group).

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Straight Stripped (X Group). 29.6128 Section 29.6128... REGULATIONS TOBACCO INSPECTION Standards Grades § 29.6128 Straight Stripped (X Group). This group consists of..., and tolerances X1 Fine Quality Straight Stripped. Heavy, ripe, firm, semielastic, normal strength and...

  20. 21 CFR 880.2200 - Liquid crystal forehead temperature strip.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Liquid crystal forehead temperature strip. 880... Personal Use Monitoring Devices § 880.2200 Liquid crystal forehead temperature strip. (a) Identification. A liquid crystal forehead temperature strip is a device applied to the forehead that is used to indicate...

  1. Real-time assessment of corneal endothelial cell damage following graft preparation and donor insertion for DMEK.

    Directory of Open Access Journals (Sweden)

    Maninder Bhogal

    Full Text Available To establish a method for assessing graft viability, in-vivo, following corneal transplantation.Optimization of calcein AM fluorescence and toxicity assessment was performed in cultured human corneal endothelial cells and ex-vivo corneal tissue. Descemet membrane endothelial keratoplasty grafts were incubated with calcein AM and imaged pre and post preparation, and in-situ after insertion and unfolding in a pig eye model. Global, macroscopic images of the entire graft and individual cell resolution could be attained by altering the magnification of a clinical confocal scanning laser microscope. Patterns of cell loss observed in situ were compared to those seen using standard ex-vivo techniques.Calcein AM showed a positive dose-fluorescence relationship. A dose of 2.67μmol was sufficient to allow clear discrimination between viable and non-viable areas (sensitivity of 96.6% with a specificity of 96.1% and was not toxic to cultured endothelial cells or ex-vivo corneal tissue. Patterns of cell loss seen in-situ closely matched those seen on ex-vivo assessment with fluorescence viability imaging, trypan blue/alizarin red staining or scanning electron microscopy. Iatrogenic graft damage from preparation and insertion varied between 7-35% and incarceration of the graft tissue within surgical wounds was identified as a significant cause of endothelial damage.In-situ graft viability assessment using clinical imaging devices provides comparable information to ex-vivo methods. This method shows high sensitivity and specificity, is non-toxic and can be used to evaluate immediate cell viability in new grafting techniques in-vivo.

  2. Imaging and quantification of endothelial cell loss in eye bank prepared DMEK grafts using trainable segmentation software.

    Science.gov (United States)

    Jardine, Griffin J; Holiman, Jeffrey D; Stoeger, Christopher G; Chamberlain, Winston D

    2014-09-01

    To improve accuracy and efficiency in quantifying the endothelial cell loss (ECL) in eye bank preparation of corneal endothelial grafts. Eight cadaveric corneas were subjected to Descemet Membrane Endothelial Keratoplasty (DMEK) preparation. The endothelial surfaces were stained with a viability stain, calcein AM dye (CAM) and then captured by a digital camera. The ECL rates were quantified in these images by three separate readers using trainable segmentation, a plug-in feature from the imaging software, Fiji. Images were also analyzed by Adobe Photoshop for comparison. Mean times required to process the images were measured between the two modalities. The mean ECL (with standard deviation) as analyzed by Fiji was 22.5% (6.5%) and Adobe was 18.7% (7.0%; p = 0.04). The mean time required to process the images through the two different imaging methods was 19.9 min (7.5) for Fiji and 23.4 min (12.9) for Adobe (p = 0.17). Establishing an accurate, efficient and reproducible means of quantifying ECL in graft preparation and surgical techniques can provide insight to the safety, long-term potential of the graft tissues as well as provide a quality control measure for eye banks and surgeons. Trainable segmentation in Fiji software using CAM is a novel approach to measuring ECL that captured a statistically significantly higher percentage of ECL comparable to Adobe and was more accurate in standardized testing. Interestingly, ECL as determined using both methods in eye bank-prepared DMEK grafts exceeded 18% on average.

  3. Moorfields technique of donor cornea mounting for femtosecond-assisted keratoplasty: use of viscoelastic in the artificial anterior chamber.

    Science.gov (United States)

    Iovieno, Alfonso; Chowdhury, Vivek; Stevens, Julian D; Maurino, Vincenzo

    2012-07-01

    Appropriate mounting and cutting of the donor sclero-corneal cap is often cumbersome during femtosecond laser-assisted keratoplasty. The authors describe a technique for donor cornea femtosecond laser cutting using ophthalmic viscoelastic devices. The donor sclero-corneal cap is mounted on the artificial anterior chamber using a dispersive ophthalmic viscoelastic device instead of saline solution. The chances of artificial anterior chamber pressure loss, inadequate applanation, and fluid leaks are consistently reduced with the use of dispersive ophthalmic viscoelastic devices. The speed of donor femtosecond laser cutting is increased. The viscosity and elasticity of dispersive ophthalmic viscoelastic devices greatly assist the procedure with regard to ease of applanation, corneal endothelium protection, and decreased distortion of the applanated cornea. Copyright 2012, SLACK Incorporated.

  4. Risk factors for graft failure after penetrating keratoplasty: 5-year follow-up from the corneal transplant epidemiological study.

    Science.gov (United States)

    Fasolo, Adriano; Capuzzo, Cristina; Fornea, Michela; Franch, Antonella; Birattari, Federica; Carito, Giuseppe; Cucco, Flavio; Prosdocimo, Giovanni; Sala, Michele; Delle Noci, Nicola; Primavera, Vito; Frigo, Anna Chiara; Grigoletto, Francesco; Ponzin, Diego

    2011-12-01

    To evaluate corneal graft survival over a 5-year period and to investigate whether factors related to the donor, eye bank practices, the recipient, surgery, and postoperative course influenced the outcome. Nine hundred ninety-eight patients were randomly selected and monitored in the subsequent 3 years from a cohort of 4500 recipients who underwent penetrating keratoplasty between 2001 and 2004. Cox univariate regression analysis was used to select variables to be included in a multivariate Cox proportional hazards model with a backward selection procedure to identify potential risk factors for graft failure. Graft survival curves were obtained from Kaplan-Meier estimates. Ectasia/thinning was the most common indication (49.1%), followed by regraft (16.1%) and pseudophakic corneal edema (PCE) (9.4%). The overall rate of graft failure was 10.7% with 6 cases of primary graft failure. Adverse reactions and complications (other than graft failure) were reported in 2.7% of patients in the first postoperative week and in 22.8% during the full follow-up period. The probability of 5-year survival was 83.0%, best in eyes with ectasia/thinning (96.0%) and less favorable in PCE (67.0%) and regraft (64.0%). Multivariate analyses showed the following variables to be linked to an increased risk of graft failure: regraft for any reason, all clinical indication except PCE, history of ocular inflammation/infection, pseudophakic/aphakic eye, vitrectomy, graft Descemet folds, adverse reactions/complications, and surgeons' low caseload. Penetrating keratoplasty shows an overall positive prognosis in the long-term. However, the probability of graft survival is largely dependent on the preoperative clinical condition and the lack of complications during follow-up.

  5. Endothelial signaling in leukocyte transmigration

    NARCIS (Netherlands)

    Hordijk, Peter

    2003-01-01

    Leukocyte transendothelial migration is a multistep process coordinated by chemokine receptors, integrins and cell adhesion molecules. The interaction between leukocytes and endothelial cells is accompanied by bidirectional signaling in both cell types, which is initiated following formation of

  6. Bird community response to filter strips in Maryland

    Science.gov (United States)

    Blank, P.J.; Dively, G.P.; Gill, D.E.; Rewa, C.A.

    2011-01-01

    Filter strips are strips of herbaceous vegetation planted along agricultural field margins adjacent to streams or wetlands and are designed to intercept sediment, nutrients, and agrichemicals. Roughly 16,000 ha of filter strips have been established in Maryland through the United States Department of Agriculture's Conservation Reserve Enhancement Program. Filter strips often represent the only uncultivated herbaceous areas on farmland in Maryland and therefore may be important habitat for early-successional bird species. Most filter strips in Maryland are planted to either native warm-season grasses or cool-season grasses and range in width from 10.7 m to 91.4 m. From 2004 to 2007 we studied the breeding and wintering bird communities in filter strips adjacent to wooded edges and non-buffered field edges and the effect that grass type and width of filter strips had on bird community composition. We used 5 bird community metrics (total bird density, species richness, scrub-shrub bird density, grassland bird density, and total avian conservation value), species-specific densities, nest densities, and nest survival estimates to assess the habitat value of filter strips for birds. Breeding and wintering bird community metrics were greater in filter strips than in non-buffered field edges but did not differ between cool-season and warm-season grass filter strips. Most breeding bird community metrics were negatively related to the percent cover of orchardgrass (Dactylis glomerata) in ???1 yr. Breeding bird density was greater in narrow (60 m) filter strips. Our results suggest that narrow filter strips adjacent to wooded edges can provide habitat for many bird species but that wide filter strips provide better habitat for grassland birds, particularly obligate grassland species. If bird conservation is an objective, avoid planting orchardgrass in filter strips and reduce or eliminate orchardgrass from filter strips through management practices. Copyright ?? 2011 The

  7. Ammonia recovery from anaerobically digested cattle manure by steam stripping.

    Science.gov (United States)

    Zeng, L; Mangan, C; Li, X

    2006-01-01

    Ammonia recovery from anaerobically digested cattle manure effluents through steam stripping was studied at a stripping tower temperature of 98-99 degrees C and a steam-water ratio approximately 56-72 g/L. The digested manure effluents were first treated by microfiltration and then the permeate was used as feed in steam stripping. The stripping performance was evaluated under different feed pH values, ammonia concentrations and temperatures. The increase of the initial feed pH does not significantly improve ammonia stripping efficiency due to the fact that the stripped effluent pH is increased during steam stripping. This suggests that steam stripping of anaerobically digested manure effluents for ammonia recovery may not need pre-raised pH. In contrast, the pH value of the synthetic ammonia wastewater containing NH4Cl dramatically decreases after steam stripping. Increasing the feed temperature slightly improves ammonia stripping efficiency, but reduces the concentration of the recovered ammonia in the condensate due to an increased condensate volume at a higher feed temperature. Therefore, the feed temperature should be controlled at an optimum point that can compromise the condensate ammonia concentration and the ammonia stripping efficiency. Experimental results indicate that recovery of ammonia from anaerobically digested cattle manure effluents as NH4OH is technically feasible.

  8. Dual deflectable beam strip engine development.

    Science.gov (United States)

    Dulgeroff, C. R.; Zuccaro, D. E.; Kami, S.; Schnelker, D. E.; Ward, J. W.

    1972-01-01

    This paper describes a dual beam thruster that has been designed, constructed, and tested. The system is suitable for two-axes attitude control and is comprised of two orthogonal strips, each capable of producing 0.30 mlb thrust and beam deflections of more than plus or minus 20 deg. The nominal specific impulse for the thruster is 5000 sec, and the thrust level from each strip can be varied from 0 to 100%. Neutralizer filaments that were developed and life tested over 2000 hours producing more than 40 mA of electron emission per watt of input power are also discussed. The system power required for clean ionizers is approximately 200 W.

  9. Nuclear reactor spring strip grid spacer

    International Nuclear Information System (INIS)

    Patterson, J.F.; Flora, B.S.

    1980-01-01

    An improved and novel grid spacer was developed for use in nuclear reactor fuel assemblies. It is comprised of a series of intersecting support strips and a peripheral support band attached to the ends of the support strips. Each of the openings into which the fuel element is inserted has a number of protruding dimples and springs extending in different directions. The dimples coact with the springs to secure the fuel rods in the openings. Compared with previous designs, this design gives more positive alignment of the support stips while allowing greater flexibility to counterbalance the effects of thermal expansion. The springs are arranged in alternating directions so that the reaction forces tend to counterbalance each other, which in turn minimizes the reaction loads on the supporting structure. (D.N.)

  10. L-strip proximity fed ga

    Directory of Open Access Journals (Sweden)

    Ashish Singh

    2014-03-01

    Full Text Available In this article, the analysis of dualband L-strip fed compact semi-circular disk microstrip patch antenna has been presented using circuit theory concept. The antenna parameters such as return loss, VSWR and radiation pattern are calculated. The effect of geometric dimensions of the proposed antenna such as length of vertical and horizontal portion of L-strip is investigated. It is found that antenna resonate at two distinct modes i.e. 1.3 GHz and 6.13 GHz for lower and upper resonance frequencies respectively. The bandwidth of the proposed antenna at lower resonance frequency is 6.61% (simulated and 10.64% (theoretical whereas at upper resonance frequency, it is 6.02% (simulated and 9.06 % (theoretical. The theoretical results are compared with IE3D simulation results as well as experimental results and they are in close agreement.

  11. Strip-till seeder for sugar beets

    Directory of Open Access Journals (Sweden)

    Peter Schulze Lammers

    2014-06-01

    Full Text Available Strip-till save costs by reducing tillage on the area of sugar beet rows only. The seeding system is characterized by a deep loosening of soil with a tine combined with a share and by following tools generating fine-grained soil as seed bed. In cooperation with the Kverneland company group Soest/Germany a strip tiller combined with precision seeder was designed and tested in field experiments. Tilling and seeding was performed in one path on fields with straw and mustard mulch. Even the plant development was slower as compared to conventional sawn sugar beets the yield was on equivalent level. Further field experiments are planned to attest constant yield, cost and energy efficiency of the seeding system.

  12. Continuous liquid sheet generator for ion stripping

    International Nuclear Information System (INIS)

    Gavin, B.; Batson, P.; Leemann, B.; Rude, B.

    1984-10-01

    Many of the technical problems of generating a large thin liquid sheet from 0.02 to 0.20 μm thick (3 to 40 μgm/cm 2 ) have been solved. It is shown that this perennial sheet is stable and consonant in dimension. Several ion beam species from the SuperHILAC have been used for evaluation; at 0.11 MeV/n. In one of three modes this sheet serves as an equivalent substitute for a carbon foil. The second mode is characterized by a solid-like charge state distribution but with a varying fraction of unstripped ions. The third mode gives stripping performance akin to a vapor stripping medium. 9 references, 7 figures

  13. Strengthening Bridges with Prestressed CFRP Strips

    Science.gov (United States)

    Siwowski, Tomasz; Żółtowski, Piotr

    2012-06-01

    Limitation of bridge's carrying bearing capacity due to aging and deterioration is a common problem faced by road administration and drivers. Rehabilitation of bridges including strengthening may be applied in order to maintain or upgrade existing bridge parameters. The case studies of strengthening of two small bridges with high modulus prestressed CFRP strips have been presented in the paper. The first one - reinforced concrete slab bridge - and the other - composite steel-concrete girder bridge - have been successfully upgraded with quite new technology. In both cases the additional CFRP reinforcement let increasing of bridge carrying capacity from 15 till 40 metric tons. The CFRP strip prestressing system named Neoxe Prestressing System (NPS), developed by multi-disciplinary team and tested at full scale in Rzeszow University of Technology, has been also described in the paper.

  14. The extent of the stop coannihilation strip

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, John [King' s College London, Theoretical Particle Physics and Cosmology Group, Department of Physics, London (United Kingdom); CERN, Theory Division, Geneva 23 (Switzerland); Olive, Keith A. [University of Minnesota, School of Physics and Astronomy, Minneapolis, MN (United States); University of Minnesota, William I. Fine Theoretical Physics Institute, School of Physics and Astronomy, Minneapolis, MN (United States); Zheng, Jiaming [University of Minnesota, School of Physics and Astronomy, Minneapolis, MN (United States)

    2014-07-15

    Many supersymmetric models such as the constrained minimal supersymmetric extension of the Standard Model (CMSSM) feature a strip in parameter space where the lightest neutralino χ is identified as the lightest supersymmetric particle, the lighter stop squark t{sub 1} is the next-to-lightest supersymmetric particle (NLSP), and the relic χ cold darkmatter density is brought into the range allowed by astrophysics and cosmology by coannihilation with the lighter stop squark t{sub 1} NLSP. We calculate the stop coannihilation strip in the CMSSM, incorporating Sommerfeld enhancement effects, and we explore the relevant phenomenological constraints and phenomenological signatures. In particular, we show that the t{sub 1} may weigh several TeV, and its lifetime may be in the nanosecond range, features that are more general than the specific CMSSM scenarios that we study in this paper. (orig.)

  15. Antenna with distributed strip and integrated electronic components

    Science.gov (United States)

    Rodenbeck, Christopher T [Albuquerque, NM; Payne, Jason A [Albuquerque, NM; Ottesen, Cory W [Albuquerque, NM

    2008-08-05

    An antenna comprises electrical conductors arranged to form a radiating element including a folded line configuration and a distributed strip configuration, where the radiating element can be in proximity to a ground conductor and/or arranged as a dipole. Embodiments of the antenna include conductor patterns formed on a printed wiring board, having a ground plane, spacedly adjacent to and coplanar with the radiating element. An antenna can comprise a distributed strip patterned on a printed wiring board, integrated with electronic components mounted on top of or below the distributed strip, and substantially within the extents of the distributed strip. Mounting of electronic components on top of or below the distributed strip has little effect on the performance of the antenna, and allows for realizing the combination of the antenna and integrated components in a compact form. An embodiment of the invention comprises an antenna including a distributed strip, integrated with a battery mounted on the distributed strip.

  16. Cathode readout with stripped resistive drift tubes

    International Nuclear Information System (INIS)

    Bychkov, V.N.; Kekelidze, G.D.; Novikov, E.A.; Peshekhonov, V.D.; Shafranov, M.D.; Zhiltsov, V.E.

    1995-01-01

    A straw tube drift chamber prototype has been constructed and tested. The straw tube material is mylar film covered with a carbon layer with a resistivity of 0.5, 30 and 70 kΩ/□. Both the anode wire and the cathode strip signals were detected to study the behaviour of the chamber in the presence of X-ray ionization. The construction and the results of the study are presented. (orig.)

  17. Neutralization of H- beams by magnetic stripping

    International Nuclear Information System (INIS)

    Jason, A.J.; Hudgings, D.W.; van Dyck, O.B.

    1981-01-01

    The stability of H - beams passing through strong magnetic fields has been relevant to accelerator transport problems and, recently, to neutral beam preparation techniques. The H - electron detachment rate was measured as a function of rest-frame electric field and provides parameters for a theoretical lifetime expression. The limitations imposed on H - transport by magnetic stripping, and neutral-beam preparation in emittance growth, magnetic fields, and beam energies are discussed. Application techniques are also briefly discussed

  18. Ram pressure stripping of tilted galaxies

    Czech Academy of Sciences Publication Activity Database

    Jáchym, Pavel; Köppen, J.; Palouš, Jan; Combes, F.

    2009-01-01

    Roč. 500, č. 2 (2009), s. 693-703 ISSN 0004-6361 R&D Projects: GA MŠk(CZ) LC06014; GA ČR GP205/08/P556 Institutional research plan: CEZ:AV0Z10030501 Keywords : interstellar medium * clusters of galaxies * gas stripping Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.179, year: 2009

  19. CLOSED-LOOP STRIPPING ANALYSIS (CLSA) OF ...

    Science.gov (United States)

    Synthetic musk compounds have been found in surface water, fish tissues, and human breast milk. Current techniques for separating these compounds from fish tissues require tedious sample clean-upprocedures A simple method for the deterrnination of these compounds in fish tissues has been developed. Closed-loop stripping of saponified fish tissues in a I -L Wheaton purge-and-trap vessel is used to strip compounds with high vapor pressures such as synthetic musks from the matrix onto a solid sorbent (Abselut Nexus). This technique is useful for screening biological tissues that contain lipids for musk compounds. Analytes are desorbed from the sorbent trap sequentially with polar and nonpolar solvents, concentrated, and directly analyzed by high resolution gas chromatography coupled to a mass spectrometer operating in the selected ion monitoring mode. In this paper, we analyzed two homogenized samples of whole fish tissues with spiked synthetic musk compounds using closed-loop stripping analysis (CLSA) and pressurized liquid extraction (PLE). The analytes were not recovered quantitatively but the extraction yield was sufficiently reproducible for at least semi-quantitative purposes (screening). The method was less expensive to implement and required significantly less sample preparation than the PLE technique. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water,

  20. Deuteron stripping reactions with Tabakin potential

    International Nuclear Information System (INIS)

    Osman, A.

    1976-05-01

    Deuteron stripping reactions are considered. Due to the strong repulsion between nucleons at very short distances, we have investigated the nuclear short-range correlations. The neutron proton nuclear potential in the deuteron is taken as a short-range repulsive core surrounded by a long-range attractive potential. The neutron-proton potential is taken as the Tabakin separable potential to take into account the short-range correlations. The differential cross-sections for deuteron stripping reactions have been calculated in two different cases by taking Yamaguchi or Breit et al type parameters for the Tabakin potential used. The angular distributions for different (d,p) stripping reactions on the different target nuclei 28 Si, 32 , 34 S, 36 Ar, 40 , 48 Ca, 50 , 52 , 54 Cr have been calculated using the DWBA calculations. Our present theoretical calculations for the angular distributions of the different reactions cosidered have been fitted to the experimental data, where good agreement is obtained. The extracted spectroscopic factors from the present work are found to be more reliable

  1. Indications for Corneal Transplantation at a Tertiary Referral Center in Tehran

    Directory of Open Access Journals (Sweden)

    Mohammad Zare

    2010-01-01

    Full Text Available Purpose: To report the indications and techniques of corneal transplantation at a tertiary referral center in Tehran over a 3-year period. Methods: Records of patients who had undergone any kind of corneal transplantation at Labbafinejad Medical Center, Tehran, Iran from March 2004 to March 2007 were reviewed to determine the indications and types of corneal transplantation. Results: During this period, 776 eyes of 756 patients (including 504 male subjects with mean age of 41.3±21.3 years underwent corneal transplantation. The most common indication was keratoconus (n=317, 40.8% followed by bullous keratopathy (n=90, 11.6%, non-herpetic corneal scars (n=62, 8.0%, infectious corneal ulcers (n=61, 7.9%, previously failed grafts (n=61, 7.9%, endothelial and stromal corneal dystrophies (n=28, 3.6%, and trachoma keratopathy (n=26, 3.3%. Other indications including Terrien′s marginal degeneration, post-LASIK keratectasia, trauma, chemical burns, and peripheral ulcerative keratitis constituted the rest of cases. Techniques of corneal transplantation included penetrating keratoplasty (n=607, 78.2%, deep anterior lamellar keratoplasty (n=108, 13.9%, conventional lamellar keratoplasty (n=44, 5.7%, automated lamellar therapeutic keratoplasty (n=8, 1.0%, and Descemet stripping endothelial keratoplasty (n=6, 0.8% in descending order. The remaining cases were endothelial keratoplasty and sclerokeratoplasty. Conclusion: In this study, keratoconus was the most common indication for penetrating keratoplasty which was the most prevalent technique of corneal transplantation. However, deep anterior lamellar keratoplasty is emerging as a growing alternative for corneal pathologies not involving the endothelium.

  2. Noise analysis due to strip resistance in the ATLAS SCT silicon strip module

    International Nuclear Information System (INIS)

    Kipnis, I.

    1996-08-01

    The module is made out of four 6 cm x 6 cm single sided Si microstrip detectors. Two detectors are butt glued to form a 12 cm long mechanical unit and strips of the two detectors are electrically connected to form 12 cm long strips. The butt gluing is followed by a back to back attachment. The module in this note is the Rφ module where the electronics is oriented parallel to the strip direction and bonded directly to the strips. This module concept provides the maximum signal-to-noise ratio, particularly when the front-end electronics is placed near the middle rather than at the end. From the noise analysis, it is concluded that the worst-case ΔENC (far-end injection) between end- and center-tapped modules will be 120 to 210 el. rms (9 to 15%) for a non-irradiated detector and 75 to 130 el. rms (5 to 9%) for an irradiated detector, for a metal strip resistance of 10 to 20 Ω/cm

  3. Falência primária pós-transplante de córnea em serviço universitário Primary corneal graft failure after penetrating keratoplasty in a university service

    Directory of Open Access Journals (Sweden)

    Flávio Eduardo Hirai

    2002-12-01

    penetrating keratoplasty from July 1999 to March 2001. Cases of primary failure (group I and patients submitted to the surgical procedure at the same period (group II were selected and compared. Information collected from donors were age, cause of death, endothelial cell count, time between death and enucleation (T1, time between enucleation and preservation of the graft (T2 and time of tissue preservation until surgery (T3. Results: 164 patients were analyzed with 21 cases of primary failure (12.8%. The mean age of the donors of group I was 43.1 years (±22.0 and from group II was 47.9 years (±18.9. There was no statistical difference between the two groups considering the time intervals (T1, T2, T3. Causes of death included trauma, cancer and heart diseases. Conclusion: Differences in all analyzed factors were not significant between both groups. The difficulties in determining the causes of primary corneal graft failure suggests a multifactorial process involved in this problem. Well-trained Eye Bank staff and notifications about postoperative complications are important to decrease the primary failure incidence.

  4. Obesity, inflammation and endothelial dysfunction.

    Science.gov (United States)

    Iantorno, M; Campia, U; Di Daniele, N; Nistico, S; Forleo, G B; Cardillo, C; Tesauro, M

    2014-01-01

    Cardiovascular disease is the leading cause of morbidity and mortality in obese individuals. Obesity dramatically increases the risk of development of metabolic and cardiovascular disease. This risk appears to originate from disruption in adipose tissue function leading to a chronic inflammatory state and to dysregulation of the endocrine and paracrine actions of adipocyte-derived factors. These, in turn, impair vascular homeostasis and lead to endothelial dysfunction. An altered endothelial cell phenotype and endothelial dysfunction are common among all obesity-related complications. A crucial aspect of endothelial dysfunction is reduced nitric oxide (NO) bioavailability. A systemic pro-inflammatory state in combination with hyperglycemia, insulin resistance, oxidative stress and activation of the renin angiotensin system are systemic disturbances in obese individuals that contribute independently and synergistically to decreasing NO bioavailability. On the other hand, pro-inflammatory cytokines are locally produced by perivascular fat and act through a paracrine mechanism to independently contribute to endothelial dysfunction and smooth muscle cell dysfunction and to the pathogenesis of vascular disease in obese individuals. The promising discovery that obesity-induced vascular dysfunction is, at least in part, reversible, with weight loss strategies and drugs that promote vascular health, has not been sufficiently proved to prevent the cardiovascular complication of obesity on a large scale. In this review we discuss the pathophysiological mechanisms underlying inflammation and vascular damage in obese patients.

  5. High pressure water jet cutting and stripping

    Science.gov (United States)

    Hoppe, David T.; Babai, Majid K.

    1991-01-01

    High pressure water cutting techniques have a wide range of applications to the American space effort. Hydroblasting techniques are commonly used during the refurbishment of the reusable solid rocket motors. The process can be controlled to strip a thermal protective ablator without incurring any damage to the painted surface underneath by using a variation of possible parameters. Hydroblasting is a technique which is easily automated. Automation removes personnel from the hostile environment of the high pressure water. Computer controlled robots can perform the same task in a fraction of the time that would be required by manual operation.

  6. The CMS Si-Strip Tracker

    CERN Document Server

    Sguazzoni, Giacomo

    2004-01-01

    The Compact Muon Solenoid (CMS) experiment at LHC features the largest Silicon Strip Tracker (SST) ever build. This device is immersed in a 4T magnetic field and, in conjunction with a Pixel system, it allows the momentum of the charged particles to be measured and the heavy-flavour final states to be tagged despite the hostile radiation environment. The impact of operating conditions and physics requirements on the SST layout and design choices is discussed and the expected performances are reviewed. The SST collaboration is now facing the production of the ~15000 modules and their assembly into the SST substructures. A status is given.

  7. The CMS Si-strip Tracker

    CERN Document Server

    Sguazzoni, Giacomo

    2004-01-01

    The Compact Muon Solenoid (CMS) experiment at LHC features the largest Silicon Strip Tracker (SST) ever build. This device is immersed in a 4T magnetic field and, in conjunction with a Pixel system, it allows the momentum of the charged particles to be measured and the heavy-flavour final states to be tagged despite the hostile radiation environment. The impact of operating conditions and physics requirements on the SST layout and design choices is discussed and the expected performances are reviewed. The SST collaboration is now facing the production of the ~15000 modules and their assembly into the SST substructures. A status is given.

  8. Tritium stripping by a catalytic exchange stripper

    International Nuclear Information System (INIS)

    Heung, L.K.; Gibson, G.W.; Ortman, M.S.

    1991-01-01

    A catalytic exchange process for stripping elemental tritium from gas streams has been demonstrated. The process uses a catalyzed isotopic exchange reaction between tritium in the gas phase and protium or deuterium in the solid phase on alumina. The reaction is catalyzed by platinum deposited on the alumina. The process has been tested with both tritium and deuterium. Decontamination factors (ration of inlet and outlet tritium concentrations) as high as 1000 have been achieved, depending on inlet concentration. The test results and some demonstrated applications are presented

  9. Congenital hereditary endothelial dystrophy with progressive sensorineural deafness (Harboyan syndrome

    Directory of Open Access Journals (Sweden)

    Abramowicz Marc

    2008-10-01

    Full Text Available Abstract Harboyan syndrome is a degenerative corneal disorder defined as congenital hereditary endothelial dystrophy (CHED accompanied by progressive, postlingual sensorineural hearing loss. To date, 24 cases from 11 families of various origin (Asian Indian, South American Indian, Sephardi Jewish, Brazilian Portuguese, Dutch, Gypsy, Moroccan, Dominican have been reported. More than 50% of the reported cases have been associated with parental consanguinity. The ocular manifestations in Harboyan syndrome include diffuse bilateral corneal edema occurring with severe corneal clouding, blurred vision, visual loss and nystagmus. They are apparent at birth or within the neonatal period and are indistinguishable from those characteristic of the autosomal recessive CHED (CHED2. Hearing deficit in Harboyan is slowly progressive and typically found in patients 10–25 years old. There are no reported cases with prelinglual deafness, however, a significant hearing loss in children as young as 4 years old has been detected by audiometry, suggesting that hearing may be affected earlier, even at birth. Harboyan syndrome is caused by mutations in the SLC4A11 gene located at the CHED2 locus on chromosome 20p13-p12, indicating that CHED2 and Harboyan syndrome are allelic disorders. A total of 62 different SLC4A11 mutations have been reported in 98 families (92 CHED2 and 6 Harboyan. All reported cases have been consistent with autosomal recessive transmission. Diagnosis is based on clinical criteria, detailed ophthalmological assessment and audiometry. A molecular confirmation of the clinical diagnosis is feasible. A variety of genetic, metabolic, developmental and acquired diseases presenting with clouding of the cornea should be considered in the differential diagnosis (Peters anomaly, sclerocornea, limbal dermoids, congenital glaucoma. Audiometry must be performed to differentiate Harboyan syndrome from CHED2. Autosomal recessive types of CHED (CHED2 and

  10. Comparative study of corneal strip extensometry and inflation tests

    OpenAIRE

    Elsheikh, Ahmed; Anderson, Kevin

    2005-01-01

    Strip extensometry tests are usually considered less reliable than trephinate inflation tests in studying corneal biomechanics. In spite of the evident simplicity of strip extensometry tests, several earlier studies preferred inflation tests in determining the constitutive relationship of the cornea and its other material properties, such as Young's modulus and the hysteresis behaviour. In this research, the deficiencies of the strip tests are discussed and a mathematical procedure presented ...

  11. DEVELOPMENT OF DEFORMATION STRIPS WHILE STRETCHING OF CYLINDRICAL SAMPLES

    Directory of Open Access Journals (Sweden)

    Y. V. Vasilevich

    2011-01-01

    Full Text Available Deformation strips have been experimentally revealed and described while stretching of cylindrical samples by means of computer thermography. It has been established that temperature of shift strip surface grows smoothly up to the stage of crack origin in material defect. Sharp growth of surface temperature occurs when tensile stresses reach tensile strength. Change in surface temperature occurs wavy after destruction (while cooling the sample. Processes of material destruction origin and development  characterize temperature changes in deformation strips.

  12. Stability of barotropic vortex strip on a rotating sphere.

    Science.gov (United States)

    Sohn, Sung-Ik; Sakajo, Takashi; Kim, Sun-Chul

    2018-02-01

    We study the stability of a barotropic vortex strip on a rotating sphere, as a simple model of jet streams. The flow is approximated by a piecewise-continuous vorticity distribution by zonal bands of uniform vorticity. The linear stability analysis shows that the vortex strip becomes stable as the strip widens or the rotation speed increases. When the vorticity constants in the upper and the lower regions of the vortex strip have the same positive value, the inner flow region of the vortex strip becomes the most unstable. However, when the upper and the lower vorticity constants in the polar regions have different signs, a complex pattern of instability is found, depending on the wavenumber of perturbations, and interestingly, a boundary far away from the vortex strip can be unstable. We also compute the nonlinear evolution of the vortex strip on the rotating sphere and compare with the linear stability analysis. When the width of the vortex strip is small, we observe a good agreement in the growth rate of perturbation at an early time, and the eigenvector corresponding to the unstable eigenvalue coincides with the most unstable part of the flow. We demonstrate that a large structure of rolling-up vortex cores appears in the vortex strip after a long-time evolution. Furthermore, the geophysical relevance of the model to jet streams of Jupiter, Saturn and Earth is examined.

  13. Strip type radiation detector and method of making same

    International Nuclear Information System (INIS)

    Jantsch, O.; Feigt, I.; Willig, W.R.

    1976-01-01

    An improved strip detector and a method for making such a detector in which a high resistivity N conduction semiconductor body has electrode strips formed thereon by diffusion is described. The strips are formed so as to be covered by an oxide layer at the surface point of the PN junction and in which the opposite side of the semiconductor body then has a substantial amount of material etched away to form a thin semiconductor upon which strip electrodes which are perpendicular to the electrodes on the first side are then placed

  14. Strip defect recognition in electrical tests of silicon microstrip sensors

    Energy Technology Data Exchange (ETDEWEB)

    Valentan, Manfred, E-mail: valentan@mpp.mpg.de

    2017-02-11

    This contribution describes the measurement procedure and data analysis of AC-coupled double-sided silicon microstrip sensors with polysilicon resistor biasing. The most thorough test of a strip sensor is an electrical measurement of all strips of the sensor; the measured observables include e.g. the strip's current and the coupling capacitance. These measurements are performed to find defective strips, e.g. broken capacitors (pinholes) or implant shorts between two adjacent strips. When a strip has a defect, its observables will show a deviation from the “typical value”. To recognize and quantify certain defects, it is necessary to determine these typical values, i.e. the values the observables would have without the defect. As a novel approach, local least-median-of-squares linear fits are applied to determine these “would-be” values of the observables. A least-median-of-squares fit is robust against outliers, i.e. it ignores the observable values of defective strips. Knowing the typical values allows to recognize, distinguish and quantify a whole range of strip defects. This contribution explains how the various defects appear in the data and in which order the defects can be recognized. The method has been used to find strip defects on 30 double-sided trapezoidal microstrip sensors for the Belle II Silicon Vertex Detector, which have been measured at the Institute of High Energy Physics, Vienna (Austria).

  15. Stability of barotropic vortex strip on a rotating sphere

    Science.gov (United States)

    Sohn, Sung-Ik; Sakajo, Takashi; Kim, Sun-Chul

    2018-02-01

    We study the stability of a barotropic vortex strip on a rotating sphere, as a simple model of jet streams. The flow is approximated by a piecewise-continuous vorticity distribution by zonal bands of uniform vorticity. The linear stability analysis shows that the vortex strip becomes stable as the strip widens or the rotation speed increases. When the vorticity constants in the upper and the lower regions of the vortex strip have the same positive value, the inner flow region of the vortex strip becomes the most unstable. However, when the upper and the lower vorticity constants in the polar regions have different signs, a complex pattern of instability is found, depending on the wavenumber of perturbations, and interestingly, a boundary far away from the vortex strip can be unstable. We also compute the nonlinear evolution of the vortex strip on the rotating sphere and compare with the linear stability analysis. When the width of the vortex strip is small, we observe a good agreement in the growth rate of perturbation at an early time, and the eigenvector corresponding to the unstable eigenvalue coincides with the most unstable part of the flow. We demonstrate that a large structure of rolling-up vortex cores appears in the vortex strip after a long-time evolution. Furthermore, the geophysical relevance of the model to jet streams of Jupiter, Saturn and Earth is examined.

  16. Pavement Stripping in Saudi Arabia: Prediction and Prevention

    Directory of Open Access Journals (Sweden)

    H.I. Al-Abdul Wahhab

    2004-12-01

    Full Text Available Pavement weathering or stripping is a major distress in highway networks in arid regions. Using the Saudi Arabian road network as a case study area, seventeen road test sections were selected, out of which eight were stripped and nine were non-stripped. Aggregates from quarries used to build these sections were also collected and subjected to detailed physical and chemical tests to evaluate the ability of these tests to distinguish between stripped and non-stripped sections. The modified Lottman test was used to distinguish between compacted mixes. In addition, the Swedish Rolling Bottle test, was also found to be effective in being able to distinguish between different asphalt-aggregates for stripping potential. Eleven anti-stripping liquid additives, lime and cement, in addition to two polymers, were evaluated for their ability to reduce/eliminate stripping potential of stripping-prone aggregates. It was found that EE-2 Polymer, Portland cement, and their combination were effective with all aggregate sources.

  17. Solute diffusion through stripped mouse duodenum.

    Science.gov (United States)

    Takeuchi, T; Ham, M; Mizumori, M; Guth, P H; Engel, E; Kaunitz, J D; Akiba, Y

    2007-12-01

    We measured villous cell intracellular pH (pH(i)) and solute diffusion between the bathing media and the epithelial cells in stripped, chambered mouse duodenum. Apical perfusion of a high CO2 solution rapidly acidified the upper villous cells with recovery after its removal. Apical zoniporide (ZP) enhanced CO(2)-induced acidification. Serosal ZP, dimethylamiloride (DMA) or stilbene anion transport inhibitors failed to alter CO(2)-induced acidification, whereas serosal high CO(2) buffer acidified the upper villous cells. Serosal 5-hydroxytryptamine rapidly acidified the upper villous cells. All serosally-perfused fluorescent compounds stained the crypt area, but not the villi or villous cells. In contrast, intravenous carboxyfluorescein quickly diffused into the interstitial space of the entire mucosa, and mucosally perfused fluorescent compound rapidly penetrated the epithelial cell layer. In muscle-stripped duodenum mounted in a small-aperture perfusion chamber, serosal solutes can readily diffuse only to the crypt cell region, whereas access to the villous epithelial cells is diffusion-limited. In contrast, rapid villous cell responses to serosally applied solutes are best explained by neural reflexes. Limited viability of the villous cells and impaired structural stability of the villi further limit long-term, villous cell functional studies of mucosal preparations mounted in small aperture diffusion chambers.

  18. Endothelial dysfunction in diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Hadi AR Hadi

    2008-01-01

    Full Text Available Hadi AR Hadi, Jassim Al SuwaidiDepartment of Cardiology and Cardiovascular Surgery, Hamad General Hospital – Hamad Medical Corporation, Doha, State of Qatar; Department of Cardioscience, Sheikh Khalifa Medical City, Abu Dhabi, UAEAbstract: Diabetes mellitus is associated with an increased risk of cardiovascular disease, even in the presence of intensive glycemic control. Substantial clinical and experimental evidence suggest that both diabetes and insulin resistance cause a combination of endothelial dysfunctions, which may diminish the anti-atherogenic role of the vascular endothelium. Both insulin resistance and endothelial dysfunction appear to precede the development of overt hyperglycemia in patients with type 2 diabetes. Therefore, in patients with diabetes or insulin resistance, endothelial dysfunction may be a critical early target for preventing atherosclerosis and cardiovascular disease. Microalbuminuria is now considered to be an atherosclerotic risk factor and predicts future cardiovascular disease risk in diabetic patients, in elderly patients, as well as in the general population. It has been implicated as an independent risk factor for cardiovascular disease and premature cardiovascular mortality for patients with type 1 and type 2 diabetes mellitus, as well as for patients with essential hypertension. A complete biochemical understanding of the mechanisms by which hyperglycemia causes vascular functional and structural changes associated with the diabetic milieu still eludes us. In recent years, the numerous biochemical and metabolic pathways postulated to have a causal role in the pathogenesis of diabetic vascular disease have been distilled into several unifying hypotheses. The role of chronic hyperglycemia in the development of diabetic microvascular complications and in neuropathy has been clearly established. However, the biochemical or cellular links between elevated blood glucose levels, and the vascular lesions remain

  19. Evaluation of silicon micro strip detectors with large read-out pitch

    International Nuclear Information System (INIS)

    Senyo, K.; Yamamura, K.; Tsuboyama, T.; Avrillon, S.; Asano, Y.; Bozek, A.; Natkaniec, Z.; Palka, H.; Rozanska, M.; Rybicki, K.

    1996-01-01

    For the development of the silicon micro-strip detector with the pitch of the readout strips as large as 250 μm on the ohmic side, we made samples with different structures. Charge collection was evaluated to optimize the width of implant strips, aluminum read-out strips, and/or the read-out scheme among strips. (orig.)

  20. Early Ahmed glaucoma valve implantation after penetrating keratoplasty leads to better outcomes in an Asian population with preexisting glaucoma.

    Directory of Open Access Journals (Sweden)

    Ming-Cheng Tai

    Full Text Available BACKGROUND: To evaluate the efficacy of Ahmed Glaucoma Valve (AGV surgery and the optimal interval between penetrating keratoplasty (PKP and AGV implantation in a population of Asian patients with preexisting glaucoma who underwent PKP. METHODOLOGY/PRINCIPAL FINDINGS: In total, 45 eyes of 45 patients were included in this retrospective chart review. The final intraocular pressures (IOPs, graft survival rate, and changes in visual acuity were assessed to evaluate the outcomes of AGV implantations in eyes in which AGV implantation occurred within 1 month of post-PKP IOP elevation (Group 1 and in eyes in which AGV implantation took place more than 1 month after the post-PKP IOP evaluation (Group 2. Factors that were associated with graft failure were analyzed, and the overall patterns of complications were reviewed. By their final follow-up visits, 58% of the patients had been successfully treated for glaucoma. After the operation, there were no statistically significant differences between the groups with respect to graft survival (p = 0.98, but significant differences for IOP control (p = 0.049 and the maintenance of visual acuity (VA (p21 mm Hg. The most common surgical complication, aside from graft failure, was hyphema. CONCLUSIONS/SIGNIFICANCE: Early AGV implantation results in a higher probability of AGV survival and a better VA outcome without increasing the risk of corneal graft failure as a result of post-PKP glaucoma drainage tube implantation.

  1. Late occurrence of granular dystrophy in bilateral keratoconus: Penetrating keratoplasty and long-term follow-up

    Directory of Open Access Journals (Sweden)

    Varsha M Rathi

    2011-01-01

    Full Text Available We report a rare case of keratoconus with granular dystrophy with a follow-up of two decades, documenting the sequential presentation of two diseases confirmed by histology and genetic studies. A 13-year-old boy was diagnosed in 1988 with keratoconus in both eyes (BE based on slit-lamp biomicroscopy findings of corneal ectasia in BE accompanied by Fleischer′s ring, Vogt′s striae, a small, old, healed hydrops. The left eye (LE had central corneal thinning and scar in the central area involving the mid and posterior stroma secondary to healed hydrops. Penetrating keratoplasty (PKP was advised. The boy was lost to follow-up till 1991 and presented with white, dot-like opacities in the central cornea in the RE only, suggestive of granular corneal dystrophy. Similar findings of white, dot-like opacities were noted in the LE in 1995 and the patient subsequently underwent PKP in BE. Histopathology of corneal buttons confirmed the presence of patchy, crystal-like orange deposits, which stained bright red with Masson′s trichrome. Mutational analysis of the TGFBI gene in patient′s DNA revealed a heterozygous mutation corresponding to a change in Arg555Trp in the keratoepithelin protein. Granular dystrophy recurred after 8 years in the RE.

  2. Subluxation of iris-sutured intraocular lenses and results of a closed chamber technique for repositioning after penetrating keratoplasty.

    Science.gov (United States)

    Jabbur, Nada S; Akpek, Esen Karamursel; Stark, Walter J

    2005-05-01

    To describe subluxation of iris-fixated intraocular lenses (IOLs) after penetrating keratoplasty (PK) as a postoperative complication and report the long-term outcomes of a closed-chamber refixation technique used in the management. This was a retrospective, noncomparative interventional case series in which 19 consecutive patient charts with a subluxated iris-fixated IOL after PK were retrospectively reviewed. Fourteen of the patients underwent surgery using a closed-chamber refixation technique. These patients were evaluated for visual outcome and surgical complications associated with the procedure. In 13 patients, postoperative follow-up was available. In all 13 cases, the fixated IOL appeared stable and remained well positioned during a follow-up period of 56 months (range, 6-122). All patients (100%) achieved improved uncorrected visual acuity. The postoperative visual acuity ranged from 20/20 to 20/100 with a mean of 20/40. Vitreous hemorrhage occurred in 1 patient, and an additional patient required a second surgery using the same technique. Both of these patients did well with a final visual acuity of 20/40 and 20/50, respectively. Subluxation of iris-fixated IOL after PK can occur as a postoperative complication. The technique that we herein describe enables secure refixation of subluxated IOLs and yields favorable long-term results.

  3. Spontaneous resolution of double anterior chamber with perforation of Descemet′s membrane in deep anterior lamellar keratoplasty

    Directory of Open Access Journals (Sweden)

    Arvind Venkatraman

    2012-01-01

    Full Text Available Deep anterior lamellar keratoplasty (DALK using Dr. Anwar′s big bubble technique was performed for a patient with granular dystrophy. Intraoperatively, a perforation of the Descemet′s membrane (DM was noted inferonasally. Though the surgery was completed, the donor graft appeared to have an intact endothelium, which was inadvertently left behind by the surgeon. Intraoperatively, there was a perforation of inferonasal DM and surgery was completed by inadvertently placing a donor with an intact endothelium. Postoperatively the patient presented with a complete DM detachment and a resultant double anterior chamber (DAC. In spite of two attempts at an air tamponade on the first and fifth post operative days, the DAC still persisted. Surprisingly, during the 6 th week follow up visit, there was a complete resolution of the DAC as well as total recovery of vision. This interesting case clearly exemplifies that, in spite of failed attempts at air tamponade, a DM detachment and a DAC due to DM perforation following a DALK procedure can resolve spontaneously with good visual outcome.

  4. Endothelial cells in dengue hemorrhagic fever.

    Science.gov (United States)

    Srikiatkhachorn, Anon; Kelley, James F

    2014-09-01

    Therapies to prevent or reverse endothelial dysfunction and vascular leak found in dengue hemorrhagic fever (DHF) have not been identified. In this review we summarize dengue viruses and the spectrum of human disease and highlight evidence of endothelial cell dysfunction in DHF based on studies in patients and mouse and tissue culture models. Evidence suggests that both virus antigen and host immune response, can cause endothelial cell dysfunction and weaken endothelial barrier integrity. We suggest possible therapeutic interventions and highlight how therapies targeting altered endothelial function might be evaluated in animal models and in patients with DHF. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. 25 CFR 170.445 - What is a strip map?

    Science.gov (United States)

    2010-04-01

    ... BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER INDIAN RESERVATION ROADS PROGRAM Planning, Design, and Construction of Indian Reservation Roads Program Facilities Irr Inventory § 170.445 What is a strip map? A strip map is a graphic representation of a section of road or other...

  6. Determination of residual stresses in roll compacted titanium strips

    CSIR Research Space (South Africa)

    Mothosi, KL

    2017-01-01

    Full Text Available induced during roll compaction of titanium strips were measured for strips of different densities. The different densities were achieved by rolling two different particle size (100 and 325 mesh) titanium powders varying the roll gap (0.1, 0.3 and 0.5 mm...

  7. Hollow Mill for Extraction of Stripped Titanium Screws: An Easy ...

    African Journals Online (AJOL)

    Removal of jammed titanium screws can be difficult due to the problem of stripping of the hexagonal heads of the screws. We present a technique of extraction of stripped screws with the use of a standard 4.5 mm stainless steel hollow mill in a patient of peri‑implant fracture of the radius fixed with a titanium locking plate 2 ...

  8. Hollow Mill for Extraction of Stripped Titanium Screws: An Easy ...

    African Journals Online (AJOL)

    screws. We present a technique of extraction of stripped screws with the use of a standard 4.5 mm stainless steel hollow mill in a patient of peri-implant fracture of the radius fixed with a titanium locking plate 2 years back. The technique is quick, safe, and cost effective. Key words: Hollow mill, stripped screws, titanium locked.

  9. Great saphenous vein stripping using nasogastric tube | Ademola ...

    African Journals Online (AJOL)

    Method and result: We describe the use of nasogastric tube in the stripping of GSV. This simple technique has been successfully applied in three patients. Conclusion: There is a need to carry out a prospective study regarding the application of this technique of GSV stripping. Keywords: Great saphenous vein, crossectomy, ...

  10. Reforestation of strip-mined lands in West Virginia

    Science.gov (United States)

    H. Spencer Potter; Sidney Weitzman; George R., Jr. Trimble

    1951-01-01

    The early 1940's witnessed a striking increase in strip-mining throughout the eastern coal region. West Virginia, with its extensive coal resources, naturally was caught in the full current of this shift in mining methods. Today the raw gash on the hillside - almost infallibly the mark of a strip-mine operation - is a familiar sight in the State.

  11. Using Comic Strips as a Book Report Alternative

    Science.gov (United States)

    Reading Teacher, 2012

    2012-01-01

    Comic strips are great to share with parents, younger students, and peers. This article presents an activity where students use a six-paneled comic strip to summarize a story. This activity allows for multiple interpretations and enhances comprehension by drawing attention to story elements.

  12. Temperature sensitivity of the oxygenation reaction of stripped ...

    African Journals Online (AJOL)

    Temperature sensitivity of the oxygenation reaction of stripped haemolysates from the freshwater fishes Labeo capensis and Ciarias gariepinus. ... of the mudfish Labeo capensis and the catfish Clarias gariepinus, stripped by gel filtration chromatography and buffered at 23°C in 0,05 M Hepes (pH 7,48), were determined at ...

  13. Tape Stripping Technique for Stratum Corneum Protein Analysis

    DEFF Research Database (Denmark)

    Clausen, Maja-Lisa; Slotved, H.-C.; Krogfelt, Karen Angeliki

    2016-01-01

    The aim of this study was to investigate the amount of protein in stratum corneum in atopic dermatitis (AD) patients and healthy controls, using tape stripping technique. Furthermore, to compare two different methods for protein assessment. Tape stripping was performed in AD patients and healthy ...

  14. Quality Tests of Double-Sided Silicon Strip Detectors

    CERN Document Server

    Cambon, T; CERN. Geneva; Fintz, P; Guillaume, G; Jundt, F; Kuhn, C; Lutz, Jean Robert; Pagès, P; Pozdniakov, S; Rami, F; Sparavec, K; Dulinski, W; Arnold, L

    1997-01-01

    The quality of the SiO2 insulator (AC coupling between metal and implanted strips) of double-sided Silicon strip detectors has been studied by using a probe station. Some tests performed on 23 wafers are described and the results are discussed. Remark This note seems to cause problems with ghostview but it can be printed without any problem.

  15. Stripping foils for the PSB H- injection system

    CERN Document Server

    Aiba, M; Goddard, B; Weterings, W

    2009-01-01

    Beam physics considerations for the stripping foil of the PSB H- injection system are described, including the arguments for the foil type, thickness, geometry and positioning. The foil performance considerations are described, including expected stripping efficiency, emittance growth, energy straggling, temperature and lifetime. The required movement ranges and tolerances are detailed, together with the assumptions used.

  16. Coiled sheet metal strip opens into tubular configuration

    Science.gov (United States)

    Park, J. J.

    1966-01-01

    Copper alloy is converted into a spring material that can be rolled into a compact coil which will spontaneously open to form a tube in the long direction of the strip. The copper alloy is passed through a furnace at a prescribed temperature while restraining the strip in the desired tubular configuration.

  17. Optical fiber cable chemical stripping fixture

    Science.gov (United States)

    Kolasinski, John R. (Inventor); Coleman, Alexander M. (Inventor)

    1995-01-01

    An elongated fixture handle member is connected to a fixture body member with both members having interconnecting longitudinal central axial bores for the passage of an optical cable therethrough. The axial bore of the fixture body member, however, terminates in a shoulder stop for the outer end of a jacket of the optical cable covering both an optical fiber and a coating therefor, with an axial bore of reduced diameter continuing from the shoulder stop forward for a predetermined desired length to the outer end of the fixture body member. A subsequent insertion of the fixture body member including the above optical fiber elements into a chemical stripping solution results in a softening of the exposed external coating thereat which permits easy removal thereof from the optical fiber while leaving a desired length coated fiber intact within the fixture body member.

  18. Digital autoradiography using silicon strip detectors

    Energy Technology Data Exchange (ETDEWEB)

    Overdick, M.

    1998-05-01

    Spatially resolving radiation detection systems operating in real time can be used to acquire autoradiographic images. An overview over alternatives to traditional autoradiography is given and the special features of these filmless methods are discussed. On this basis the design of a system for digital autoradiography using silicon strip detectors is presented. Special emphasis is put on the physical background of the detection process in the semiconductor and on the self-triggering read-out technique. The practical performance of the system is analyzed with respect to energy and spatial resolution. This analysis is complemented by case studies from cell biology (especially electrophoresis), botany and mineralogy. Also the results from a time-resolved autoradiographic experiment are presented. (orig.) 80 refs.

  19. Silicon strip detectors for the ATLAS upgrade

    CERN Document Server

    Gonzalez Sevilla, S; The ATLAS collaboration

    2011-01-01

    The Large Hadron Collider at CERN will extend its current physics program by increasing the peak luminosity by one order of magnitude. For ATLAS, one of the two general-purpose experiments of the LHC, an upgrade scenario will imply the complete replacement of its internal tracker due to the harsh conditions in terms of particle rates and radiation doses. New radiation-hard prototype n-in-p silicon sensors have been produced for the short-strip region of the future ATLAS tracker. The sensors have been irradiated up to the fluences expected in the high-luminous LHC collider. This paper summarizes recent results on the performance of the irradiated n-in-p detectors.

  20. Dynamic underground stripping. Innovative technology summary report

    International Nuclear Information System (INIS)

    1995-04-01

    Dynamic Underground Stripping (DUS) is a combination of technologies targeted to remediate soil and ground water contaminated with organic compounds. DUS is effective both above and below the water table and is especially well suited for sites with interbedded sand and clay layers. The main technologies comprising DUS are steam injection at the periphery of a contaminated area to heat permeable subsurface areas, vaporize volatile compounds bound to the soil, and drive contaminants to centrally located vacuum extraction wells; electrical heating of less permeable sediments to vaporize contaminants and drive them into the steam zone; and underground imaging such as Electrical Resistance Tomography to delineate heated areas to ensure total cleanup and process control. A full-scale demonstration was conducted on a gasoline spill site at Lawrence Livermore National Laboratory in Livermore, California from November 1992 through December 1993

  1. Endothelial dysfunction: a comprehensive appraisal

    Directory of Open Access Journals (Sweden)

    Vilariño Jorge O

    2006-02-01

    Full Text Available Abstract The endothelium is a thin monocelular layer that covers all the inner surface of the blood vessels, separating the circulating blood from the tissues. It is not an inactive organ, quite the opposite. It works as a receptor-efector organ and responds to each physical or chemical stimulus with the release of the correct substance with which it may maintain vasomotor balance and vascular-tissue homeostasis. It has the property of producing, independently, both agonistic and antagonistic substances that help to keep homeostasis and its function is not only autocrine, but also paracrine and endocrine. In this way it modulates the vascular smooth muscle cells producing relaxation or contraction, and therefore vasodilatation or vasoconstriction. The endothelium regulating homeostasis by controlling the production of prothrombotic and antithrombotic components, and fibrynolitics and antifibrynolitics. Also intervenes in cell proliferation and migration, in leukocyte adhesion and activation and in immunological and inflammatory processes. Cardiovascular risk factors cause oxidative stress that alters the endothelial cells capacity and leads to the so called endothelial "dysfunction" reducing its capacity to maintain homeostasis and leads to the development of pathological inflammatory processes and vascular disease. There are different techniques to evaluate the endothelium functional capacity, that depend on the amount of NO produced and the vasodilatation effect. The percentage of vasodilatation with respect to the basal value represents the endothelial functional capacity. Taking into account that shear stress is one of the most important stimulants for the synthesis and release of NO, the non-invasive technique most often used is the transient flow-modulate "endothelium-dependent" post-ischemic vasodilatation, performed on conductance arteries such as the brachial, radial or femoral arteries. This vasodilatation is compared with the

  2. Evaluation of anatomy comic strips for further production and applications.

    Science.gov (United States)

    Shin, Dong Sun; Kim, Dae Hyun; Park, Jin Seo; Jang, Hae Gwon; Chung, Min Suk

    2013-09-01

    The corresponding author of the study has been sketching comic strips to explain anatomy in a humorous manner. All the anatomy comic strips, including those in Korean (650 episodes) and English (451 episodes), can be viewed on the homepage (http://anatomy.co.kr). Such comic strips were created with the aim of assisting medical students. However, their impact was unknown, and therefore, we surveyed the students' responses. We noted that anatomy grades were better in the students who read the comic strips. The comics helped the trainees chat with individuals with and without a medical background. The authors also considered comments on the problems with the comic strips and attempted to find solutions. The episodes are being currently used and further produced for educational purposes. To support this effort, the readers' valuable opinions will be continuously collected and assessed.

  3. Evaluation of anatomy comic strips for further production and applications

    Science.gov (United States)

    Shin, Dong Sun; Kim, Dae Hyun; Park, Jin Seo; Jang, Hae Gwon

    2013-01-01

    The corresponding author of the study has been sketching comic strips to explain anatomy in a humorous manner. All the anatomy comic strips, including those in Korean (650 episodes) and English (451 episodes), can be viewed on the homepage (http://anatomy.co.kr). Such comic strips were created with the aim of assisting medical students. However, their impact was unknown, and therefore, we surveyed the students' responses. We noted that anatomy grades were better in the students who read the comic strips. The comics helped the trainees chat with individuals with and without a medical background. The authors also considered comments on the problems with the comic strips and attempted to find solutions. The episodes are being currently used and further produced for educational purposes. To support this effort, the readers' valuable opinions will be continuously collected and assessed. PMID:24179697

  4. Comparative study of corneal strip extensometry and inflation tests.

    Science.gov (United States)

    Elsheikh, Ahmed; Anderson, Kevin

    2005-06-22

    Strip extensometry tests are usually considered less reliable than trephinate inflation tests in studying corneal biomechanics. In spite of the evident simplicity of strip extensometry tests, several earlier studies preferred inflation tests in determining the constitutive relationship of the cornea and its other material properties, such as Young's modulus and the hysteresis behaviour. In this research, the deficiencies of the strip tests are discussed and a mathematical procedure presented to take account of these deficiencies when obtaining the corneal material properties. The study also involves testing 10 pairs of porcine corneas using both strip extensometry and trephinate inflation techniques and the results are subjected to mathematical back analysis in order to determine the stress-strain behaviour. The behaviour obtained from the strip extensometry tests and using the new mathematical analysis procedure is shown to match closely the inflation test results.

  5. Superconducting strip detectors as position sensitive particle detectors

    Energy Technology Data Exchange (ETDEWEB)

    Scherschel, M. (Lab. fuer Festkoerperphysik, ETH-Hoenggerberg, Zuerich (Switzerland) Paul Scherrer Inst., Solid State Div., Villigen (Switzerland)); Finkbeiner, F. (Paul Scherrer Inst., Solid State Div., Villigen (Switzerland)); Zhao, S.P. (Paul Scherrer Inst., Solid State Div., Villigen (Switzerland)); Jaggi, A. (Paul Scherrer Inst., Solid State Div., Villigen (Switzerland)); Maier, T. (Paul Scherrer Inst., Solid State Div., Villigen (Switzerland)); Lerch, P. (Paul Scherrer Inst., Solid State Div., Villigen (Switzerland)); Zehnder, A. (Paul Scherrer Inst., Solid State Div., Villigen (Switzerland)); Ott, H.R. (Lab. fuer Festkoerperphysik, ETH-Hoenggerberg, Zuerich (Switzerland) Paul Scherrer Inst., Solid State Div., Villigen (Switzerland))

    1994-02-01

    The feasibility of using of current-biased superconducting strips for radiation detection is investigated. Narrow Ta strips are exposed to 5.5 MeV [alpha]-particle radiation and the rise-time of the induced voltage pulses is measured as function of temperature and bias current. The rise-time of the voltage signal strongly depends on the site on the strip which is hit by the [alpha]-particle. In order to determine the spatial resolution of a superconducting strip detector, position-sensitive measurements were performed. The maximum lateral resolution estimated so far is 25[mu]m in a 7[mu]m wide, 340 nm thick and 0.6 mm long Ta-strip. (orig.)

  6. Development and application of potentiometric stripping analysis

    Directory of Open Access Journals (Sweden)

    Babincev Ljiljana M.

    2017-01-01

    Full Text Available This paper focuses on the voltammetric determination of lead, cadmium and zinc in water. Two ways of determining were investigated: individually and all three metals simultaneously. The experiments were performed using the Potentiometric Stripping Analysis (PSA. Determination of metals in real samples was preceded by preliminary tests. Preliminary investigations were performed in order to determine the optimal conditions of measurement. It was concluded that the process of determining was for most part influenced by: pH, time of metals extraction, stirring rate of the solution and the thickness of the mercury layer on the working electrode. The smallest concentrations of metals which can be determined using this method are: for lead 22.48 μg dm-3, for cadmium 16.23 μg dm-3 and for zinc 18.75 μg dm-3. The obtained results deviated from the actual 1.12% for lead, 1.91% for cadmium and 1.81% for zinc. All tests (individually and simultaneously were conducted from model solution with concentration as follows: 44.96 μg dm-3 for lead, 32.47 μg dm-3 for cadmium and 37.50 μg dm-3 for zinc. The results of individual measurements deviated by 1.02% lead, 1.90% for cadmium and 1.89% for zinc. Simultaneously the contents were lower than real for: -4.58% for lead, cadmium for -1.91% and -1.89% for zinc. For the conditions determined, except for lead, deviations did not exceed ±2% . This indicates that Potentiometric Stripping Analysis is a good way of individual and simultaneous determination of lead, cadmium and zinc and for determination of their concentrations in water (river and groundwater.

  7. Study of inter-strip gap effects and efficiency for full energy detection of double sided silicon strip detectors

    International Nuclear Information System (INIS)

    Fisichella, M.; Forneris, J.; Grassi, L.

    2015-01-01

    We performed a characterization of Double Sided Silicon Strip Detectors (DSSSD) with the aim to carry out a systematic study of the inter-strip effects on the energy measurement of charged particles. The dependence of the DSSSD response on ion, energy and applied bias has been investigated. (author)

  8. Endothelial Glycocalyx and Cardiopulmonary Bypass.

    Science.gov (United States)

    Myers, Gerard J; Wegner, Julie

    2017-09-01

    On the outer surface of a human cell there is a dense layer of complex carbohydrates called glycocalyx, also referred to as glycans or the sugar coating on the cell surface, which is composed of a complex array of oligosaccharide and polysaccharide glucose chains that are covalently bonded to proteoglycans and lipids bound to the cell membrane surface. Studies of an intact endothelial glycocalyx layer (EGL) have revealed a number of critical functions that relate the importance of this protective layer to vascular integrity and permeability. These functions include the following: stabilization and maintenance of the vascular endothelium, an active reservoir of essential plasma proteins (i.e., albumin, antithrombin, heparan sulfate, and antioxidants), a buffer zone between the blood (formed elements) and the surface of the endothelium, and a mechanotransducer to detect changes in shear stress that facilitate vascular tone. There have been numerous review articles about the structure and function of endothelial glycocalyx over the past two decades, yet there still remains a significant knowledge gap in the perfusion literature around the importance of EGL. Perioperative fluid management and gaseous microemboli can both contribute to the damage/degradation of endothelial glycocalyx. A damaged EGL can result in systemic and myocardial edema, platelet and leukocyte adhesion, fluid extravasation, and contributes to microvascular perfusion heterogeneity. Knowledge of the importance of endothelial glycocalyx will enable clinicians to have a better understanding of the impact of gaseous microbubbles, hyperoxia, and ischemic reperfusion injury during cardiac surgery. The purpose of this article is to provide an in depth review of the EGL and how this protective barrier impacts the microcirculation, fluid homeostasis, inflammation, and edema during cardiac surgery.

  9. Microstructural research on hot strips of low carbon steel produced by a compact strip production line under different thermal histories

    International Nuclear Information System (INIS)

    Yu Hao; Chen Qixiang; Kang Yonglin; Sun Yi

    2005-01-01

    Coupons with the same composition and thickness (4.0 mm nominal gauge) obtained from hot strips of low carbon steel underwent a series of investigations to analyze the microstructural characteristics and mechanisms responsible for their differences in mechanical properties. Two different industrial technologies were adopted, although the strips used in this research were produced on the same Compact Strip Production (CSP) line. One of the strips was produced with a routine γ→α CSP thermal history, but the other with a γ→α→γ* conventional thermal history. The only difference between them was that one technology had a α→γ* thermal history. Different specimens of both types of strips were prepared for metallographic observation, tensile tests, electron back-scattered diffraction tests and positron annihilation technique tests. Experimental results showed that the differences in mechanical properties could be ascribed to dissimilarities not only in the grain size and textural components but also in dislocation density

  10. New Concept of Cultivation Using Limited Strip-Tillage with Strip Shallow Irrigation

    Directory of Open Access Journals (Sweden)

    Yazid Ismi Intara

    2014-04-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE Dry land is one of land resources which potentially used for food crop cultivation, especially in the areas which have light to medium technical obstacles. The development of technology to improve soil quality in marginal lands to be productive lands is still widely open for agricultural development in Indonesia. Rooting medium quality can be improved by changing soil tillage method and observing the proper crop irrigation technology. It can be the solution for crop cultivation in clay loam soil. This study aimed to obtain water movement model in a minimally-tilled clay soil with strip shallow irrigation. The concept is limited soil-tillage with strip shallow irrigation method, water supply technique, and crop water requirement. Method used in this study includes developing water movement model (software development in a minimally-tilled clay soil with subsurface irrigation. In the final stages, research also conducted water movement analysis testing apparatus in the laboratory, field validation of the subsurface irrigation performance, and cultivation technique testing to chili pepper growth (Capsicum annuumL.. The development of water movement simulation on a limited strip-tillage with subsurface irrigation uses the concept to quantify the amount of water in the soil. The analysis of movement pattern was demonstrated on contour patterns. It showed that the wetting process can reach depth zone – 5 cm to the rooting zone. It was an important discovery on the development of minimum stripe tillage soil with subsurface irrigation. Specifically, it can be concluded that: the result of fitting by eyes to diffusivity graphic and water content obtained the required parameter values for soil physical properties. It was then simulated on horizontal water movement model on a minimum strip-tillage with strip shallow irrigation /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso

  11. Visual acuity and refraction after deep anterior lamellar keratoplasty with and without successful big-bubble formation.

    Science.gov (United States)

    Feizi, Sepehr; Javadi, Mohammad Ali; Rastegarpour, Ali

    2010-11-01

    To compare visual acuity and refractive outcomes after Anwar's deep anterior lamellar keratoplasty (DALK) between eyes with and without successful big-bubble formation. In this retrospective comparative study, keratoconic eyes undergoing DALK with the big-bubble technique were divided into 2 groups: group 1 in which a bared Descemet membrane (DM) was achieved and group 2 in which layer-by-layer manual dissection was performed because of the lack of big-bubble formation after several intrastromal air injections. The 2 groups were compared with respect to best spectacle-corrected visual acuity, keratometric astigmatism, and refractive error at months 1, 3, 6, and 12, and at least 3 months after complete suture removal. A total of 123 keratoconic eyes were enrolled. A bared DM was successfully achieved in 100 eyes (81.3%) (group 1), whereas in 23 eyes (18.7%) (group 2), some posterior stroma was left in place. The mean follow-up period was 21 ± 9 months in group 1 and 23 ± 9 months in group 2 (P = 0.37). Postoperative best spectacle-corrected visual acuity was significantly better in group 1 than in group 2 at months 1, 3, 6, and 12. But, at the final examinations, there was no significant difference between the study groups (0.24 ± 0.21 logarithm of the minimum angle of resolution in group 1 and 0.32 ± 0.14 logarithm of the minimum angle of resolution in group 2; P = 0.18). The 2 groups were comparable regarding keratometric astigmatism and spherical equivalent refractive error throughout the follow-up period. Retention of posterior corneal stroma delayed visual recovery after DALK using Anwar's technique, but the participants in this group ultimately reached the same levels of visual acuity as observed in the bared-DM group.

  12. Immunohistological Evaluation of the Healing Response at the Flap Interface in Patients With LASIK Ectasia Requiring Penetrating Keratoplasty

    Science.gov (United States)

    Esquenazi, Salomon; Esquenazi, Isi; Grunstein, Lev; He, Juicheng; Bazan, Haydee

    2010-01-01

    PURPOSE To evaluate the healing response at the flap interface in corneas with LASIK ectasia that required penetrating keratoplasty (PK). METHODS Corneas of five patients who developed corneal ectasia after LASIK (range: 2.5 to 5 years postoperative) were collected after corneal transplant surgery. The corneas were bisected and processed for conventional histologic analysis and immunofluorescence. RESULTS Light microscopy showed a hypocellular fibrotic scar at the wound margin compared with the adjacent corneal stroma in all eyes. All corneas had positive staining for alpha-smooth muscle actin (SMA), a myofibroblast marker. In one eye, alpha-SMA cells were located in the fibrotic scar region in the area of the semicircular ring of haze along the margin of the LASIK flap corresponding to an area of epithelial ingrowth. In all other eyes, alpha-SMA positive cells were fewer and mainly located in the superficial stroma under the epithelial wound margin surface. Type III collagen was minimal or absent in the central zone and wound margin of all corneas except for the cornea with epithelial ingrowth present in the hypercellular fibrotic scar region. Chondroitin sulfate was stronger in the periphery of the flap wound coinciding with a higher presence of alpha-SMA–positive cells in that region. Positive staining for matrix metalloproteinase 9 (MMP-9) in the paracentral wound margin scar was seen. CONCLUSIONS A wound-healing process characterized by absence of significant fibrosis and myofibroblasts at the wound edge in the flap interface was noted in all keratectatic eyes. However, changes in the composition of collagen and the presence of MMP-9 at the wound edge several years after LASIK indicates active wound remodeling that may explain the ongoing loss of tissue and tendency of the cornea to bulge. PMID:19714799

  13. Long-term outcomes of penetrating keratoplasty in keratoconus:analysis of the factors associated with final visual acuities

    Directory of Open Access Journals (Sweden)

    Jin A Choi

    2014-06-01

    Full Text Available AIM: To investigate the long-term results of penetrating keratoplasty (PK in patients with keratoconus (KC and to evaluate factors that might influence the final visual outcome.METHODS:We retrospectively reviewed the data of all patients with clinical KC who had undergone PK by a single corneal surgeon in a single center from May 1980 to December 2005. The age of the patients, preoperative best-corrected visual acuity (BCVA, corneal thickness, death to preservation time, and preservation to transplantation time were recorded. Additionally, postoperative complications such as graft rejection, development of glaucoma and specular microscopy were checked during the follow-up.RESULTS:Sixty-nine eyes from 69 patients were finally included. The follow-up period was 8.64±6.13y. Graft rejection occurred in 4 eyes of 69 cases (5.8%, and the time to graft rejection was 2.1±1.3y. A Kaplan–Meier survival analysis showed that the estimated cumulative probability of graft rejection at 6, 13, and 17y after PK were 95.6%, 90.0%, and 78.8%, respectively. When we evaluated factors that might influence final BCVA in eyes, no disparity donor-host trephine size (same graft size as well as higher spherical equivalent, and average K-value were associated with higher final BCVA. (P=0.006, 0.051, 0.092, and 0.021 in eyes with follow-up <8y; P=0.068, 0.065, and 0.030 in eyes with follow-up ≥8y, respectively.CONCLUSION: The long-term results of PK in patients with KC were favorable with a high percentage of good BCVA. Less myopic change and low average K-reading, as well as a surgical technique using the same size donor-recipient button may provide better visual outcomes particularly in patients with KC.

  14. Hyperopia correction by noncontact holmium: YAG laser thermal keratoplasty: five-pulse treatments with 1-year follow-up.

    Science.gov (United States)

    Kohnen, T; Villarreal, R; Menefee, R; Berry, M; Koch, D D

    1997-11-01

    Previous noncontact holmium (Ho): YAG laser thermal keratoplasty (LTK) studies on correction of low to moderate hyperopia have used treatment algorithms based on ten-pulse, variable-pulse-energy treatment parameters. The purpose of this study was to evaluate the safety, effectiveness, and stability of new five-pulse, constant-pulse-energy treatment parameters for noncontact Ho:YAG LTK. Thirty-nine hyperopic patient eyes [up to +4.75 diopters (D) refractive error] were treated using simultaneous noncontact delivery of Ho:YAG laser energy (Sunrise) with two symmetrical octagonal rings of eight spots per ring and radial spot patterns on centerline diameters of 5 and 6 mm (group A), 6 and 7 mm (group B), or 6.5 and 7.5 mm (group C). Each ring of spots received five pulses of laser light at 5 Hz pulse repetition frequency and a fixed pulse energy of 240 mJ. Thirty of the 39 patient eyes (77%) had 1-year follow-up exams. At 1 year, the mean Snellen uncorrected distance visual acuity lines gained was 3.7 +/- 0.5/6.8 +/- 2.7/5.3 +/- 3.3 for groups A, B, and C. The mean changes in subjective manifest refraction (spherical equivalent) were -2.08 +/- 1.13 D, -1.83 +/- 0.88 D, -1.22 +/- 0.88 D for groups A, B, and C respectively. None of the eyes lost two or more lines of spectacle-corrected distance visual acuity. There were no clinically significant complications in any patient. This clinical study indicates that five-pulse noncontact LTK treatments of low hyperopia are safe and effective. The stability has to be confirmed with longer follow-up.

  15. Membrane air stripping utilizing a plate and frame configuration

    International Nuclear Information System (INIS)

    Boswell, S.T.

    1991-01-01

    Membrane air stripping has recently been proposed as a possible method to remove volatile organic chemicals (VOCs) and radon from drinking water supplies. Current and anticipated regulatory requirements, driven by health consequences, make the removal of these contaminants mandatory. This work examines the use of plate and frame membrane air stripping for the removal of VOCs and radon from a water supply. The theoretical basis of membrane air stripping and a literature review are included. The advantages of membrane air stripping versus other methods of removal, as well as the advantages of a plate and frame configuration versus a hollow fiber configuration for membrane air stripping are discussed. Multiple regression/correlation techniques are used to model mass transfer coefficients and fluid resistances. An economic evaluation is performed using the developed models. The costs of comparable membrane and packed tower air stripping systems are 4.86 cents per thousand gallons versus 4.36 cents per thousand gallons, respectively. This work indicates that plate and frame membrane air stripping may, in fact, prove to be an economical alternative to packed tower aeration and carbon adsorption for the removal of VOCs and radon

  16. Inadvertent Screw Stripping During Ankle Fracture Fixation in Elderly Bone

    Science.gov (United States)

    Dinah, A. Feroz; Mears, Simon C.; Knight, Trevor A.; Soin, Sandeep P.; Campbell, John T.; Belkoff, Stephen M.

    2011-01-01

    Poor screw purchase because of osteoporosis presents difficulties in ankle fracture fixation. The aim of our study was to determine if cortical thickness, unicortical versus bicortical purchase, and bone mineral density are predictors of inadvertent screw stripping and overtightening. Ten paired cadaver ankles (average donor age, 81.7 years; range, 50-97 years) were used for the study. Computed tomography scanning with phantoms of known density was used to determine the bone density along the distal fibula. A standard small-fragment, 7-hole, one-third tubular plate was applied to the lateral surface of the fibula, with 3 proximal bicortical cortical screws and 2 distal unicortical cancellous screws. A posterior plate, in which all 5 screws were cortical and achieved bicortical purchase, was subsequently applied to the same bones and positioned so that the screw holes did not overlap. A torque sensor was used to measure the torque of each screw during insertion (Ti) and then stripping (Ts). The effect of bone density, screw location, cortical thickness, and unicortical versus bicortical purchase on Ti and Ts was checked for significance (P screws were inadvertently stripped and 12% were overtightened. Despite 21% of the screws being stripped or being at risk for stripping, we found no significant predictors to warn of impending screw stripping. Additional work is needed to identify clinically useful predictors of screw stripping. PMID:23569675

  17. [Endothelial dysfunction in hypertension--clinical implications].

    Science.gov (United States)

    Kosmala, Wojciech

    2002-04-01

    Endothelial cells produce both vasodilatating compounds as nitric oxide, prostacycline, endothelial derived hyperpolarising factor and counteracting substances known as endothelial derived contracting factors: endothelin, tromboxan A2, prostaglandin H2, free oxygen radicals. Natural balance between both groups affects blood perfusion of various tissues and constitutes important element in blood pressure control. More and more attention is paid to endothelial dysfunction in patogenesis of hypertension. In a number of studies endothelial dysfunction in hypertensive patients was found out as decreased release of nitric oxide or increased production of endothelin. Principle mechanism of impaired function of endothelium in hypertension seems to be decreased production and increased degradation of nitric oxide mainly due to free oxygen radicals. Favorable effects in improvement of endothelial function were achieved by using ACE inhibitors, AT1 receptor blockers and calcium channel antagonists.

  18. Isolation and culture of pulmonary endothelial cells.

    OpenAIRE

    Ryan, U S

    1984-01-01

    Methods for isolation, identification and culture of pulmonary endothelial cells are now routine. In the past, methods of isolation have used proteolytic enzymes to detach cells; thereafter, traditional methods for cell passaging have used trypsin/EDTA mixtures. Cells isolated and passaged using proteolytic enzymes have been useful in establishing the field and in verifying certain endothelial properties. However, there is a growing awareness of the role of endothelial cells in processing vas...

  19. Reductive stripping process for uranium recovery from organic extracts

    Science.gov (United States)

    Hurst, F.J. Jr.

    1983-06-16

    In the reductive stripping of uranium from an organic extractant in a uranium recovery process, the use of phosphoric acid having a molarity in the range of 8 to 10 increases the efficiency of the reductive stripping and allows the strip step to operate with lower aqueous to organic recycle ratios and shorter retention time in the mixer stages. Under these operating conditions, less solvent is required in the process, and smaller, less expensive process equipment can be utilized. The high strength H/sub 3/PO/sub 4/ is available from the evaporator stage of the process.

  20. New technology for the production of magnesium strips and sheets

    Directory of Open Access Journals (Sweden)

    R. Kawalla

    2008-07-01

    Full Text Available A new production technology for magnesium strip, based on twin-roll-casting and strip rolling was developed in Freiberg Germany. By means of this economic method it is possible to produce strips in deep drawing quality with good forming properties in order to satisfy the request for low cost Mg sheets in the automotive and electronic industry. Both, coils as single sheets, were manufactured and rolled to a thickness of 1mm(0,5 mm. The technology of the new process and the properties of the twin-roll-casted material and the final sheets are presented.

  1. Profile of a science comic strip author

    CERN Multimedia

    Anaïs Schaeffer

    2014-01-01

    After studying visual arts, Lison Bernet worked as a lock keeper, waitress, grape picker, farm labourer and chef before finally returning to her first love: drawing. Today a scientific illustrator, Lison is the author of the cartoon strip "La BD du LHC", which she draws every month for LHC France (by CNRS/IN2P3 and CEA/Irfu, see here).   © Lison Bernet. Lison’s career path might seem somewhat chaotic, but it is a reflection of the artist herself: original and passionate. “I never do anything by half measures. When I got into cooking for example [Lison took a chef training course for adults], I became completely wrapped up in it. I even went as far as cooking roasts during my lunch hour, just for practice…” says Lison. On completing the course, Lison got a job as a chef on a canal boat. And it was then that she got the drawing bug again. “I started keeping an illustrated travel diary,” she says. &ldquo...

  2. Operation of the CMS silicon strip tracker

    CERN Document Server

    Gotra, Yuri

    2011-01-01

    The CMS Silicon Strip Tracker (SST), comprising 9.6 million readout channels from 15148 modules covering an area of about 200 square meters, needs to be precisely calibrated in order to correctly interpret and reconstruct the events recorded from the detector, ensuring that the SST performance fully meets the physics research program of the CMS experiment. Calibration constants may be derived from promptly reconstructed events as well as from pedestal runs gathered just before the acquisition of physics runs. These calibration procedures were exercised in summer and winter 2009, when the CMS detector was commissioned using cosmic muons and proton-proton collisions at a center-of-mass energies of 900 GeV and 2.36 TeV. During these data taking periods the performance of the SST was carefully studied: the noise of the detector, the data integrity, the signal-to-noise ratio, the hit reconstruction efficiency, the calibration workflows have been all checked for stability and for different conditions, at the module...

  3. An improved rolled strip pulse forming line.

    Science.gov (United States)

    Li, Song; Qian, Bao-Liang; Yang, Han-Wu; Gao, Jing-Ming; Liu, Zhao-Xi

    2013-06-01

    The rolled strip pulse forming line (RSPFL) has advantages of compactness, portability, and long pulse achievability which could well meet the requirements of industrial application of the pulse power technology. In this paper, an improved RSPFL with an additional insulator between the grounded conductors is investigated numerically and experimentally. Results demonstrate that the jitter on the flat-top of the output voltage waveform is reduced to 3.8% due to the improved structure. Theoretical analysis shows that the electromagnetic coupling between the conductors of the RSPFL strongly influences the output voltage waveform. Therefore, the new structure was designed to minimize the detrimental effect of the electromagnetic coupling. Simulation results show that the electromagnetic coupling can be efficiently reduced in the improved RSPFL. Experimental results illustrate that the improved RSPFL, with dimensions and weight of Φ 290 × 250 mm and 16 kg, when used as a simple pulse forming line, could generate a well shaped quasi-square pulse with output power of hundreds of MW and pulse duration of 250 ns. Importantly, the improved RSPFL was successfully used as a Blumlein pulse forming line, and a 10.8 kV, 260 ns quasi-square pulse was obtained on a 2 Ω dummy load. Experiments show reasonable agreement with numerical analysis.

  4. Nanoscale Test Strips for Multiplexed Blood Analysis, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of our nanoscale test strips, or nanostrips, is to provide rapid, low-cost, powerful multiplexed analyses in a diminutive form so that whole body health...

  5. Acrylamide content and color development in fried potato strips

    DEFF Research Database (Denmark)

    Pedreschi, F.; Kaack, K.; Granby, Kit

    2006-01-01

    and 45 min; 90 degrees C for 3 and 10 min); (iii) immersed in a citric acid solution of 10 g/L for an hour; (iv) immersed in a sodium pyrophosphate solution of 10 g/L for an hour. Acrylamide content and color was determined in the potato strips after frying. Immersed strips in water for 120 min showed...... (13 5, 327 and 564 mu m acrylamide/kg for 150, 170 and 190 degrees C, respectively). Potato strip immersion in citric acid solution of 10 g/L reduced much more the acrylamide formation after frying than the strip immersion in sodium pyrophosphate solution of 10 g/L (53% vs. 17%, respectively, average...

  6. Digital simulation of anodic stripping voltammetry from thin film electrodes

    International Nuclear Information System (INIS)

    Magallanes, J.F.

    1984-01-01

    The anodic stripping voltammetry (ASV) is routinely applied to control of Cu(II) in heavy water in the primary cooling loop of the Nuclear Power Reactor. The anodic stripping voltammetry (ASV) is a very well-known technique in electroanalytical chemistry. However, due to the complexity of the phenomena, it is practised with the fundamentals of empiric considerations. A geometric model for the anodic stripping voltammetry (ASV) from thin film electrodes which can be calculated by explicit digital simulation method is proposed as a possibility of solving the electrochemically reversible, cuasi-reversible and irreversible reactions under linear potential scan and multiple potential scans. (Until now the analytical mathematical method was applied to reversible reactions). All the results are compared with analytical solutions and experimental results and it permits to conclude that the anodic stripping voltammetry (ASV) can be studied with the simplicity and potentialities of explicit digital simulation methods. (M.E.L.) [es

  7. Data acquisition software for the CMS strip tracker

    International Nuclear Information System (INIS)

    Bainbridge, R; Cripps, N; Fulcher, J; Radicci, V; Wingham, M; Baulieu, G; Bel, S; Delaere, C; Drouhin, F; Gill, K; Mirabito, L; Cole, J; Jesus, A C A; Giassi, A; Giordano, D; Gross, L; Hahn, K; Mersi, S; Nikolic, M; Tkaczyk, S

    2008-01-01

    The CMS silicon strip tracker, providing a sensitive area of approximately 200 m 2 and comprising 10 million readout channels, has recently been completed at the tracker integration facility at CERN. The strip tracker community is currently working to develop and integrate the online and offline software frameworks, known as XDAQ and CMSSW respectively, for the purposes of data acquisition and detector commissioning and monitoring. Recent developments have seen the integration of many new services and tools within the online data acquisition system, such as event building, online distributed analysis, an online monitoring framework, and data storage management. We review the various software components that comprise the strip tracker data acquisition system, the software architectures used for stand-alone and global data-taking modes. Our experiences in commissioning and operating one of the largest ever silicon micro-strip tracking systems are also reviewed

  8. The Construction of the CMS Tracker Silicon Strip Modules

    CERN Document Server

    Chiorboli, Massimiliano

    2006-01-01

    The procedures followed for the construction of the Silicon Strip Modules to be used in the CMS Tracker Detector are described. The steps of the production chain are described, and the results are given.

  9. Stability of flow over axisymmetric bodies with porous suction strips

    Science.gov (United States)

    Nayfeh, A. H.; Reed, H. L.

    1982-01-01

    Linear triple deck, closed form solutions for mean-flow quantities are developed for axisymmetric incompressible flow past a body with porous strips. The solutions account for upstream influence and are linear superpositions of the flow past the body without suction plus the perturbations due to the suction strips. Flow past the suctionless body is calculated using the Transition Analysis Program System, and a simple linear optimization scheme to determine number, spacing, and mass flow rate through the strips on an axisymmetric body is developed using the linear, triple-deck, closed-form solutions. The theory is demonstrated by predicting optimal strip distributions, and the effect of various adverse pressure-gradient situations on stability is studied.

  10. The New Silicon Strip Detectors for the CMS Tracker Upgrade

    CERN Document Server

    Dragicevic, Marko

    2010-01-01

    The first introductory part of the thesis describes the concept of the CMS experiment. The tasks of the various detector systems and their technical implementations in CMS are explained. To facilitate the understanding of the basic principles of silicon strip sensors, the subsequent chapter discusses the fundamentals in semiconductor technology, with particular emphasis on silicon. The necessary process steps to manufacture strip sensors in a so-called planar process are described in detail. Furthermore, the effects of irradiation on silicon strip sensors are discussed. To conclude the introductory part of the thesis, the design of the silicon strip sensors of the CMS Tracker are described in detail. The choice of the substrate material and the complex geometry of the sensors are reviewed and the quality assurance procedures for the production of the sensors are presented. Furthermore the design of the detector modules are described. The main part of this thesis starts with a discussion on the demands on the ...

  11. Results of Laboratory Testing of Advanced Power Strips: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Earle, L.; Sparn, B.

    2012-08-01

    This paper describes the results of a laboratory investigation to evaluate the technical performance of advanced power strip (APS) devices when subjected to a range of home entertainment center and home office usage scenarios.

  12. Continuous Strip Reduction Test Simulating Tribological Conditions in Ironing

    DEFF Research Database (Denmark)

    Üstünyagiz, Esmeray; Nielsen, Chris Valentin; Christiansen, Peter

    2017-01-01

    materials, surface roughnesses, normal pressure, sliding length, sliding speed, interface temperature and lubrication. This paper proposes a new Strip Reduction Test (SRT) for industrial ironing processes that is capable of replicating the highly severe tribological conditions that are experienced during...

  13. Nanoscale Test Strips for Multiplexed Blood Analysis, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of our nanoscale test strips, or nanostrips, is to provide rapid, low-cost, powerful multiplexed analyses in a diminutive form so that whole body health...

  14. High Pressure Water Stripping Using Multi-Orifice Nozzles

    Science.gov (United States)

    Hoppe, David

    1999-01-01

    The use of multi-orifice rotary nozzles greatly increases the speed and stripping effectiveness of high pressure water blasting systems, but also greatly increases the complexity of selecting and optimizing the operating parameters. The rotational speed of the nozzle must be coupled with its transverse velocity as it passes across the surface of the substrate being stripped. The radial and angular positions of each orifice must be included in the analysis of the nozzle configuration. Orifices at the outer edge of the nozzle head move at a faster rate than the orifices located near the center. The energy transmitted to the surface from the impact force of the water stream from an outer orifice is therefore spread over a larger area than energy from an inner orifice. Utilizing a larger diameter orifice in the outer radial positions increases the total energy transmitted from the outer orifice to compensate for the wider distribution of energy. The total flow rate from the combination of all orifices must be monitored and should be kept below the pump capacity while choosing orifice to insert in each position. The energy distribution from the orifice pattern is further complicated since the rotary path of all the orifices in the nozzle head pass through the center section. All orifices contribute to the stripping in the center of the path while only the outer most orifice contributes to the stripping at the edge of the nozzle. Additional orifices contribute to the stripping from the outer edge toward the center section. With all these parameters to configure and each parameter change affecting the others, a computer model was developed to track and coordinate these parameters. The computer simulation graphically indicates the cumulative affect from each parameter selected. The result from the proper choices in parameters is a well designed, highly efficient stripping system. A poorly chosen set of parameters will cause the nozzle to strip aggressively in some areas

  15. The CMS Silicon Strip Tracker: Design and Production Status

    CERN Document Server

    Affolder, A A

    2004-01-01

    The CMS Silicon Strip Tracker (SST) will be equipped with 15000 silicon micro-strip detector modules covering a surface of 200 m^2. This paper details the SST layout and updates the status of construction. Progress in the fabrication of module components is detailed, with focus on the front-end hybrid and silicon sensor production. The assembly of over 2200 modules using industrial methods is described; the quality assurance protocols have resulted in modules of extremely high mechanical and electrical quality.

  16. Area Strip Mine Reclamation Using Dredged Material: A Field Demonstration.

    Science.gov (United States)

    1980-07-01

    reclamation of abandoned strip mine spoils.l1 Regraded areas can be seeded or planted with cuttings or seedlings ; however, most strip mine areas are...Helianthus petiolaris PLAINS THREE-AWN GRASS Aristida oligantha PRICKLEY LETTUCE Lactuca scariola QUACK GRASS Agropyron repens RED TOP Agrostis alba REED...Arctium minus FILD THISTLE Cirsiumn vlare BUL THISTLE Cirsiun aulgare A9’ COMMON SOW THISTLE Sonchus uliginosus PRICKLY LETTUCE Lactuca scariola A10

  17. An analysis of stripping to isolated analog resonances

    International Nuclear Information System (INIS)

    Pessoa, E.F.; Toledo Piza, A.F.R. de.

    1983-04-01

    The Feshbach projection formalism is used to calculate the form factors for the (d,n) stripping process to isolated analog resonances. These are used in a standard DWBA stripping calculation in which the radial integration over all space is accomplished by including outerspace contributions evaluated along the complex contours of Vincent and Fortune. It turns out that the shape and magnitude of the predicted cross section is quite insensitive to the continuum proton wave emanating from the resonant residual state. (Author) [pt

  18. Optimising carbon electrode materials for adsorptive stripping voltammetry

    OpenAIRE

    Chaisiwamongkhol, K; Batchelor-McAuley, C; Sokolov, S; Holter, J; Young, N; Compton, R

    2017-01-01

    Different types of carbon electrode materials for adsorptive stripping voltammetry are studied through the use of cyclic voltammetry. Capsaicin is utilised as a model compound for adsorptive stripping voltammetry using unmodified and modified basal plane pyrolytic graphite (BPPG) electrodes modified with multi-walled carbon nanotubes, carbon black or graphene nanoplatelets, screen printed carbon electrodes (SPE), carbon nanotube modified screen printed electrodes, and carbon paste electrodes....

  19. A new strips tracker for the upgraded ATLAS ITk detector

    Science.gov (United States)

    David, C.

    2018-01-01

    The ATLAS detector has been designed and developed to function in the environment of the present Large Hadron Collider (LHC). At the next-generation tracking detector proposed for the High Luminosity LHC (HL-LHC), the so-called ATLAS Phase-II Upgrade, the fluences and radiation levels will be higher by as much as a factor of ten. The new sub-detectors must thus be faster, of larger area, more segmented and more radiation hard while the amount of inactive material should be minimized and the power supply to the front-end systems should be increased. For those reasons, the current inner tracker of the ATLAS detector will be fully replaced by an all-silicon tracking system that consists of a pixel detector at small radius close to the beam line and a large area strip tracker surrounding it. This document gives an overview of the design of the strip inner tracker (Strip ITk) and summarises the intensive R&D activities performed over the last years by the numerous institutes within the Strips ITk collaboration. These studies are accompanied with a strong prototyping effort to contribute to the optimisation of the Strip ITk's structure and components. This effort culminated recently in the release of the ATLAS Strips ITk Technical Design Report (TDR).

  20. Efficient ozone, sulfate, and ammonium free resist stripping process

    Science.gov (United States)

    Dattilo, Davide; Dietze, Uwe

    2014-07-01

    In recent years, photomask resist strip and cleaning technology development was substantially driven by the industry's need to prevent surface haze formation through the elimination of sulfuric acid and ammonium hydroxide from these processes. As a result, conventional SPM (H2SO4 + H2O2) was replaced with Ozone water (DIO3) for resist stripping and organic removal to eliminate chemical haze formation [1, 2]. However, it has been shown that DIO3 basted strip and clean process causes oxidative degradation of photomask materials [3, 4]. Such material damage can affect optical properties of funcitional mask layers, causeing CD line-width, phase, transmission and reflection changes, adversely affecting image transfer during the Lithography process. To overcome Ozone induced surface damage, SUSS MicroTec successfully developed a highly efficient strip process, where photolysis of DIO3 is leading to highly reactive hydroxyl radical formation, as the main contribution to hydrocarbon removal without surface damage [5]. This technology has been further extended to a final clean process, which is utilizing pure DI water for residual organic material removal during final clean [6]. Recently, SUS MicroTec did also successfully release strip and clean processes which completely remove NH4OH, eliminating any chemicals known today to induce haze [7]. In this paper we show the benefits of these new technologies for highly efficient sulfate and ammonium free stripping and cleaning processes.

  1. Development of a thin steel strip casting process. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Williams, R.S.

    1994-04-01

    This is a comprehensive effort to develop direct strip casting to the point where a pilot scale program for casting carbon steel strip could be initiated. All important aspects of the technology were being investigated, however the program was terminated early due to a change in the business strategy of the primary contractor, Armco Inc. (focus to be directed at specialty steels, not low carbon steel). At termination, the project was on target on all milestones and under budget. Major part was casting of strip at the experiment casting facility. A new caster, capable of producing direct cast strip of up to 12 in. wide in heats of 1000 and 3000 lb, was used. A total of 81 1000-1200 lb heats were cast as well as one test heat of 3000 lb. Most produced strip of from 0.016 to 0.085 in. thick. Process reliability was excellent for short casting times; quality was generally poor from modern hot strip mill standards, but the practices necessary for good surface quality were identified.

  2. Endothelial dysfunction after non-cardiac surgery

    DEFF Research Database (Denmark)

    Søndergaard, E S; Fonnes, S; Gögenur, I

    2015-01-01

    BACKGROUND: More than 50% of patients with increased troponin levels after non-cardiac surgery have an impaired endothelial function pre-operatively. Non-invasive markers of endothelial function have been developed for the assessment of endothelial dysfunction. The aim of this paper was to system......BACKGROUND: More than 50% of patients with increased troponin levels after non-cardiac surgery have an impaired endothelial function pre-operatively. Non-invasive markers of endothelial function have been developed for the assessment of endothelial dysfunction. The aim of this paper...... was to systematically review the literature to evaluate the association between non-cardiac surgery and non-invasive markers of endothelial function. METHODS: A systematic search was conducted in MEDLINE, EMBASE and Cochrane Library Database according to the PRISMA guidelines. Endothelial dysfunction was described only...... with non-invasive measurements done both pre- and post-operatively and published in English. All types of non-cardiac surgery and both men and women of all ages were included. RESULTS: We found 1722 eligible studies in our search, and of these, five studies fulfilled our inclusion and exclusion criteria...

  3. Prevalence of positive microbiology results from donor cornea tissue in different methods of corneal transplantation.

    Science.gov (United States)

    Garg, Sumit; Said, Bishoy; Farid, Marjan; Steinert, Roger F

    2013-02-01

    To evaluate the prevalence of positive microbiology results (culture and/or Gram stain) in donor cornea tissue with newer transplant methods and to assess if the results subsequently correlate with higher incidence of clinical infection. A retrospective review of the microbiology records of 569 consecutive corneal transplants from July 2006 through July 2010 was performed to evaluate positive microbiology results in routine evaluation of cornea donor tissue. Microbiologic results were available for 544 of 569 transplants. The remaining 25 cases did not have specimens submitted for microbiologic analysis. In cases with results available, 46 (8.5%) positive reports occurred. In 10 of the 46 cases, Gram stain results were positive with subsequent negative cultures. Analysis revealed that the prevalence of positive results was 6 in 137 (4.4%), 14 in 127 (11.0%), and 26 in 271 (9.6%) for femtosecond laser-enabled keratoplasty, Descemet stripping automated endothelial keratoplasty, and conventional penetrating keratoplasty, respectively; 9 femtosecond deep anterior lamellar keratoplasty had no positive results. There was no significant relationship between the types of transplant procedures and the occurrence of positive microbiologic results (P = 0.08). The overall incidence of clinical infection was found to be 0.4% (2 of 569); however, only 1 case (1 of 569 or 0.2%), which was a Candida albicans infection after Descemet stripping automated endothelial keratoplasty, was attributable to the donor. Of 25 cases in which microbiology studies were not performed, none developed a clinical infection. Prevalence of positive microbiologic results and subsequent infections do not appear to be increased with the method of donor handling used for newer techniques for keratoplasty.

  4. Test-beam evaluation of heavily irradiated silicon strip modules for ATLAS Phase-II Strip Tracker Upgrade

    CERN Document Server

    Blue, Andrew; The ATLAS collaboration

    2018-01-01

    The planned HL-LHC (High Luminosity LHC) is being designed to maximise the physics potential of the LHC with 10 years of operation at instantaneous luminosities of 7.5x1034cm−2s−1. A consequence of this increased luminosity is the expected radiation damage requiring the tracking detectors to withstand hadron equivalences to over 1x1015 1 MeV neutron equivalent per cm2 in the ATLAS Strips system. The silicon strip tracker exploits the concept of modularity. Fast readout electronics, deploying 130nm CMOS front-end electronics are glued on top of a silicon sensor to make a module. The radiation hard n-in-p micro-strip sensors used have been developed by the ATLAS ITk Strip Sensor collaboration and produced by Hamamatsu Photonics. A series of tests were performed at the DESY-II and CERN SPS test beam facilities to investigate the detailed performance of a strip module with both 2.5cm and 5cm length strips before and after irradiation with 8x1014neqcm−2 protons and a total ionising dose of 37.2MRad. The DURA...

  5. Resveratrol and Endothelial Nitric Oxide

    Directory of Open Access Journals (Sweden)

    Ning Xia

    2014-10-01

    Full Text Available Nitric oxide (NO derived from the endothelial NO synthase (eNOS has antihypertensive, antithrombotic, anti-atherosclerotic and antiobesogenic properties. Resveratrol is a polyphenol phytoalexin with multiple cardiovascular and metabolic effects. Part of the beneficial effects of resveratrol are mediated by eNOS. Resveratrol stimulates NO production from eNOS by a number of mechanisms, including upregulation of eNOS expression, stimulation of eNOS enzymatic activity and reversal of eNOS uncoupling. In addition, by reducing oxidative stress, resveratrol prevents oxidative NO inactivation by superoxide thereby enhancing NO bioavailability. Molecular pathways underlying these effects of resveratrol involve SIRT1, AMPK, Nrf2 and estrogen receptors.

  6. Dysfunctional Endothelial Progenitor Cells in Metabolic Syndrome

    Science.gov (United States)

    Devaraj, Sridevi; Jialal, Ishwarlal

    2012-01-01

    The metabolic syndrome (MetS) is highly prevalent and confers an increased risk of diabetes and cardiovascular disease. A key early event in atherosclerosis is endothelial dysfunction. Numerous groups have reported endothelial dysfunction in MetS. However, the measurement of endothelial function is far from optimum. There has been much interest recently in a subtype of progenitor cells, termed endothelial progenitor cells (EPCs), that can circulate, proliferate, and dfferentiate into mature endothelial cells. EPCs can be characterized by the assessment of surface markers, CD34 and vascular endothelial growth factor receptor-2, VEGFR-2 (KDR). The CD34+KDR+ phenotype has been demonstrated to be an independent predictor of cardiovascular outcomes. MetS patients without diabetes or cardiovascular diseases have decreased EPC number and functionality as evidenced by decreased numbers of colony forming units, decreased adhesion and migration, and decreased tubule formation. Strategies that have been shown to upregulate and enhance EPC number and functionality include statins, angiotensin converting enzyme inhibitors, angiotensin receptor blockers, and peroxisome-proliferator-activating-receptor gamma agonists. Mechanisms by which they affect EPC number and functionality need to be studied. Thus, EPC number and/or functionality could emerge as novel cellular biomarkers of endothelial dysfunction and cardiovascular disease risk in MetS. PMID:21941528

  7. Tailoring of the titanium surface by preparing cardiovascular endothelial extracellular matrix layer on the hyaluronic acid micro-pattern for improving biocompatibility.

    Science.gov (United States)

    Li, Jingan; Zhang, Kun; Wu, Juejue; Zhang, Lijuan; Yang, Ping; Tu, Qiufen; Huang, Nan

    2015-04-01

    It has been proved that high molecular weight hyaluronic acid (HMW-HA, 1×10(6) Da) micro-strips on titanium (Ti) surface can elongate the human vascular endothelial cell (EC) morphology, subsequently enhance endothelial extracellular matrix (ECM) deposition in our previous work. The HMW-HA micro-strips were anticipated to possess good hemocompatibility and EC compatibility simultaneously. However, the single HMW-HA micro-strips on Ti substrate showed bad hemocompatibility. To solve this problem, a method combining HA micro-pattern and EC decellularization was developed, and the endothelial extracellular matrix layer on the HA micro-pattern (ECM/HAP) showed excellent hemocompatibility and endothelial progenitor cells (EPCs) compatibility (cell number: 14.3±0.5×10(5) cells/cm2>2.2±0.7×10(5) cells/cm2 on ECM/TiOH, 7.5±1.3×10(5) cells/cm2 on TiOH, 3.4±0.9×10(5) cells/cm2 on TiOH/HAP and 3.6±1.2×10(5) cells/cm2 on Ti). We also found that the ECM/HAP coating could significantly inhibit the excessive proliferation of smooth muscle cells (SMCs) (cck-8 absorption: 0.25±0.06biomaterials surface, which might provide a potential and effective method for surface modification of cardiovascular devices. Copyright © 2015. Published by Elsevier B.V.

  8. STRIPPED ELLIPTICAL GALAXIES AS PROBES OF ICM PHYSICS. I. TAILS, WAKES, AND FLOW PATTERNS IN AND AROUND STRIPPED ELLIPTICALS

    Energy Technology Data Exchange (ETDEWEB)

    Roediger, E. [Hamburger Sternwarte, Universität Hamburg, Gojensbergsweg 112, D-21029 Hamburg (Germany); Kraft, R. P.; Nulsen, P. E. J.; Forman, W. R.; Machacek, M.; Randall, S.; Jones, C. [Harvard/Smithsonian Center for Astrophysics, 60 Garden Street MS-4, Cambridge, MA 02138 (United States); Churazov, E. [MPI für Astrophysik, Karl-Schwarzschild-Str. 1, Garching, D-85741 (Germany); Kokotanekova, R., E-mail: eroediger@hs.uni-hamburg.de [AstroMundus Master Programme, University of Innsbruck, Technikerstr. 25/8, 6020 Innsbruck (Austria)

    2015-06-10

    Elliptical cluster galaxies are progressively stripped of their atmospheres due to their motion through the intracluster medium (ICM). Deep X-ray observations reveal the fine-structure of the galaxy’s remnant atmosphere and its gas tail and wake. This fine-structure depends on dynamic conditions (galaxy potential, initial gas contents, orbit through the host cluster), orbital stage (early infall, pre-/post-pericenter passage), and ICM plasma properties (thermal conductivity, viscosity, magnetic field structure). We aim to disentangle dynamic and plasma effects in order to use stripped ellipticals as probes of ICM plasma properties. This first paper of a series investigates the hydrodynamics of progressive gas stripping by means of inviscid hydrodynamical simulations. We distinguish a long-lasting initial relaxation phase and a quasi-steady stripping phase. During quasi-steady stripping, the ICM flow around the remnant atmosphere resembles the flow around solid bodies, including a “deadwater” region in the near wake. Gas is stripped from the remnant atmosphere predominantly at its sides via Kelvin–Helmholtz instabilities. The downstream atmosphere is largely shielded from the ICM wind and thus shaped into a tail. Observationally, both this “remnant tail” and the stripped gas in the wake can appear as a “tail”, but only in the wake can galactic gas mix with the ambient ICM. While the qualitative results are generic, the simulations presented here are tailored to the Virgo elliptical galaxy M89 (NGC 4552) for the most direct comparison to observations. Papers II and III of this series describe the effect of viscosity and compare to Chandra and XMM-Newton observations, respectively.

  9. Acrylamide content and color development in fried potato strips

    DEFF Research Database (Denmark)

    Pedreschi, F.; Kaack, K.; Granby, Kit

    2006-01-01

    Acrylamide formation and changes in color of fried potato strips was investigated in relation to frying temperature and three treatments before frying. Potato strips (0.8 x 0.8 x 5 cm) of Bintje variety were fried at 150, 170 and 190 degrees C until reaching moisture contents of similar to 40 g...... water/100 g (total basis). Prior to frying, potato strips were treated in one of the following ways: (i) immersed in distilled water for 0 min (control), 60 min and 120 min; (ii) blanched in hot water at six different time-temperature combinations (50 degrees C for 40 and 80 min; 70 degrees C for 10...... and 45 min; 90 degrees C for 3 and 10 min); (iii) immersed in a citric acid solution of 10 g/L for an hour; (iv) immersed in a sodium pyrophosphate solution of 10 g/L for an hour. Acrylamide content and color was determined in the potato strips after frying. Immersed strips in water for 120 min showed...

  10. Prototype indicator strip for tank ammunition. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bates, B.; Griest, W.

    1993-10-31

    Combustible nitrocellulose ordnance casings offer advantages of: light weight, low cost, low detectability, and quick cycling of rounds by immediate disposal. However, mechanical strength is degraded with time by the action of humidity and nitroester diffusion through the casing to adhesives. The primary development effort of this study is a means to detect nitroester migration to the crucial skive joint which binds an assortment of warhead choices to propellant casings. This work has developed a prototype colorimetric indicator strip which, when applied in a field environment, produces a purple tint proportional to casing nitroester concentration, and inversely proportional to remaining adhesive joint strength. This work addressed the three steps in indicator strip use: (1) A suggested protocol for indicator strip preparation was developed. Various coatings, support reagents, and backings were examined resulting in a choice of polyethylene tape coating over separate AB- and C-impregnated cellulose punches. Various methods of punch creation and impregnation were tried resulting in stirred aqueous solutions and suspensions of AB and C, respectively. (2) Suggested protocols for indicator strip application to lab backings and field casings were developed. After chemical stripper was applied to the alumina-polyurethane paint on casings, C and AB punches were stacked and double-tape sealed. (3) A means for indicator strip monitoring was developed. From known time of indicator reaction, casing humidity, and indicator color, a means for field concentration determination was determined. Lab time-lapse photography was used to calibrate the indicator at a single level of humidity.

  11. Theoretical study of H- stripping with a wiggler magnet

    International Nuclear Information System (INIS)

    Hutson, R.L.

    1991-01-01

    The first step for injecting protons into the LAMPF Proton Storage Ring (PSR) at LANL is to strip a beam of 800-MeV H - ions to H 0 with a 1.8-T dipole magnet. Because of the finite lifetime of energetic H - ions in the magnetic field, their trajectories bend before stripping causing the angular spread of the beam, and therefore its emittance, to grow during the stripping process. In the case of the PSR, the horizontal beam emittance grows by a factor of roughly three during injection. As a consequence, beam losses in the ring are significantly greater than they would be if there were not emittance growth. A speculative technique is proposed in which the beam divergence growth and resulting emittance growth is reduced by stripping the H - in a wiggler magnet whose transverse field alternates in direction as a function of position along the beam axis. The wiggler field configuration is adjusted so that the angular beam spread introduced during passage through one unidirectional-field increment of path is relatively small and so that 99.99% of the beam is stripped after passing through the whole magnet. With careful field design the net added angular beam spread is reduced because the incremental angular spreads are painted back and forth over the same small range. In the hypothetical case described, the calculated emittance growth and beam loss increase are significantly smaller than those calculated for a conventional stripper magnet. 3 refs., 3 figs

  12. Combined HLA matched limbal stem cells allograft with amniotic membrane transplantation as a prophylactic surgical procedure to prevent corneal graft rejection after penetrating keratoplasty: case report

    Directory of Open Access Journals (Sweden)

    Paolo Capozzi

    2014-09-01

    Full Text Available Purpose. To determine if the use of combined HLA matched limbal stem cells allograft with amniotic membrane transplantation (AMT is a safe and effective prophylactic surgical procedure to prevent corneal graft after penetrating keratoplasty (PK. Methods. We report the case of a 17 years old patient with a history of congenital glaucoma, trabeculectomy and multiple corneal graft rejections, presenting total limbal cell deficiency. To reduce the possibility of graft rejection in the left eye after a new PK, a two step procedure was performed. At first the patient underwent a combined HLA matched limbal stem cells allograft (LAT and AMT and then, 10 months later, a new PK. Results. During 12 months of follow-up, the corneal graft remained stable and smooth, with no sign of graft rejection. Conclusions. In our patient, the prophylactic use of LAT from HLA-matched donors and AMT before PK, may result in a better prognosis of corneal graft survival.

  13. 'Blue bubble' technique: an ab interno approach for Descemet separation in deep anterior lamellar keratoplasty using trypan blue stained viscoelastic device.

    Science.gov (United States)

    Livny, Eitan; Bahar, Irit; Hammel, Naama; Nahum, Yoav

    2018-04-01

    In this study, we examined a novel variant of 'big-bubble' deep anterior lamellar keratoplasty using trypan-blue-stained viscoelastic device for the creation of a pre-descemetic bubble. Ten corneoscleral rims were mounted on an artificial anterior chamber (AC). The AC was filled with air through a limbal paracentesis. A Melles' triangulated spatula was inserted through the paracentesis, with its tip penetrating the AC, was then slightly retracted and pushed into the deep stroma above the roof of the paracentesis. A mixture of trypan blue and viscoelastic device (Healon, Abbott Medical Optics, Abbott Park, Illinois) was injected into this intra-stromal pocket using a 27-G cannula to create a pre-descemetic separation bubble. Bubble type and visualization of dyed viscoelastic device were noted. The method was later employed in three cases. In all 10 corneoscleral rims, the technique successfully created a visible pre-descemetic (type 1) bubble that could be expanded up to the predicted diameter of trephination. Subsequent trephination and the removal of corneal stroma were uneventful. In two out of four clinical cases, a type 1 bubble was created, while in two others, visco-dissection failed and dyed viscoelastic was seen in the AC. The presented technique holds promise of being a relatively easy to perform, predictable and well-controlled alternative for achieving a type 1 bubble during deep anterior lamellar keratoplasty surgery. The trypan-blue-stained viscoelastic device facilitates proper visualization and control of the separation bubble and assists in identifying the penetrance to the separation bubble prior to removal of the stromal cap. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

  14. Phonon thermal conductance of disordered graphene strips with armchair edges

    International Nuclear Information System (INIS)

    Shi Lipeng; Xiong Shijie

    2009-01-01

    Based on the model of lattice dynamics together with the transfer matrix technique, we investigate the thermal conductances of phonons in quasi-one-dimensional disordered graphene strips with armchair edges using Landauer formalism for thermal transport. It is found that the contributions to thermal conductance from the phonon transport near von Hove singularities is significantly suppressed by the presence of disorder, on the contrary to the effect of disorder on phonon modes in other frequency regions. Besides the magnitude, for different widths of the strips, the thermal conductance also shows different temperature dependence. At low temperatures, the thermal conductance displays quantized features of both pure and disordered graphene strips implying that the transmission of phonon modes at low frequencies are almost unaffected by the disorder

  15. Efficiency measurements for 3D silicon strip detectors

    Energy Technology Data Exchange (ETDEWEB)

    Parzefall, Ulrich, E-mail: ulrich.parzefall@physik.uni-freiburg.d [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany); Dalla Betta, Gian-Franco [INFN Trento and Universita di Trento, via Sommarive 14, 38050 Povo di Trento (Italy); Boscardin, Maurizio [FBK-irst, Center for Materials and Microsystems, via Sommarive 18, 38050 Povo di Trento (Italy); Eckert, Simon [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany); Eklund, Lars; Fleta, Celeste [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Jakobs, Karl; Koehler, Michael; Kuehn, Susanne; Pahn, Gregor [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany); Parkes, Chris; Pennicard, David [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Ronchin, Sabina [FBK-irst, Center for Materials and Microsystems, via Sommarive 18, 38050 Povo di Trento (Italy); Zoboli, Andrea [INFN Trento and Universita di Trento, via Sommarive 14, 38050 Povo di Trento (Italy); Zorzi, Nicola [FBK-irst, Center for Materials and Microsystems, via Sommarive 18, 38050 Povo di Trento (Italy)

    2010-11-01

    Silicon strip detectors are widely used as part of the inner tracking layers in particle physics experiments. For applications at the luminosity upgrade of the Large Hadron Collider (LHC), the sLHC, silicon detectors with extreme radiation hardness are required. The 3D detector design, where electrodes are processed from underneath the strips into the silicon bulk material, provides a way to enhance the radiation tolerance of standard planar silicon strip detectors. Detectors with several innovative 3D designs that constitute a simpler and more cost-effective processing than the 3D design initially proposed were connected to read-out electronics from LHC experiments and subsequently tested. Results on the amount of charge collected, the noise and the uniformity of charge collection are given.

  16. Synchronizing a Triple Dragline Stripping System in Thick Overburden

    Directory of Open Access Journals (Sweden)

    Erdem Bülent

    2017-06-01

    Full Text Available This study addresses the use of combined stripping systems to investigate the technical feasibility of extracting thick coal seams underlying deep overburden strata. The possibility of using multiple draglines in tandem with bucket wheel excavator systems is explored. Pit geometry design alternatives incorporating a triple dragline excavation fleet with bucket wheel excavator-cross pit spreader subsystems (BWE+XPS are examined. A production simulation algorithm, which emphasizes synchronizing excavator units in the triple dragline system, is developed. The combined methodology is evaluated in Sector-D of the Afşin-Elbistan lignite basin, one of the most important resources for electricity production in Turkey. The results reveal that a combined stripping fleet may successfully perform overburden stripping at the predetermined rate and uncover coal seams.

  17. Performance studies of the CMS Strip Tracker before installation

    Energy Technology Data Exchange (ETDEWEB)

    Adam, W.; et al.

    2009-06-01

    In March 2007 the assembly of the Silicon Strip Tracker was completed at the Tracker Integration Facility at CERN. Nearly 15% of the detector was instrumented using cables, fiber optics, power supplies, and electronics intended for the operation at the LHC. A local chiller was used to circulate the coolant for low temperature operation. In order to understand the efficiency and alignment of the strip tracker modules, a cosmic ray trigger was implemented. From March through July 4.5 million triggers were recorded. This period, referred to as the Sector Test, provided practical experience with the operation of the Tracker, especially safety, data acquisition, power, and cooling systems. This paper describes the performance of the strip system during the Sector Test, which consisted of five distinct periods defined by the coolant temperature. Significant emphasis is placed on comparisons between the data and results from Monte Carlo studies.

  18. Performance studies of the CMS Strip Tracker before installation

    CERN Document Server

    Adam, Wolfgang; Dragicevic, Marko; Friedl, Markus; Fruhwirth, R; Hansel, S; Hrubec, Josef; Krammer, Manfred; Oberegger, Margit; Pernicka, Manfred; Schmid, Siegfried; Stark, Roland; Steininger, Helmut; Uhl, Dieter; Waltenberger, Wolfgang; Widl, Edmund; Van Mechelen, Pierre; Cardaci, Marco; Beaumont, Willem; de Langhe, Eric; de Wolf, Eddi A; Delmeire, Evelyne; Hashemi, Majid; Bouhali, Othmane; Charaf, Otman; Clerbaux, Barbara; Dewulf, Jean-Paul; Elgammal, Sherif; Hammad, Gregory Habib; de Lentdecker, Gilles; Marage, Pierre Edouard; Vander Velde, Catherine; Vanlaer, Pascal; Wickens, John; Adler, Volker; Devroede, Olivier; De Weirdt, Stijn; D'Hondt, Jorgen; Goorens, Robert; Heyninck, Jan; Maes, Joris; Mozer, Matthias Ulrich; Tavernier, Stefaan; Van Lancker, Luc; Van Mulders, Petra; Villella, Ilaria; Wastiels, C; Bonnet, Jean-Luc; Bruno, Giacomo; De Callatay, Bernard; Florins, Benoit; Giammanco, Andrea; Gregoire, Ghislain; Keutgen, Thomas; Kcira, Dorian; Lemaitre, Vincent; Michotte, Daniel; Militaru, Otilia; Piotrzkowski, Krzysztof; Quertermont, L; Roberfroid, Vincent; Rouby, Xavier; Teyssier, Daniel; Daubie, Evelyne; Anttila, Erkki; Czellar, Sandor; Engstrom, Pauli; Harkonen, J; Karimaki, V; Kostesmaa, J; Kuronen, Auli; Lampen, Tapio; Linden, Tomas; Luukka, Panja-Riina; Maenpaa, T; Michal, Sebastien; Tuominen, Eija; Tuominiemi, Jorma; Ageron, Michel; Baulieu, Guillaume; Bonnevaux, Alain; Boudoul, Gaelle; Chabanat, Eric; Chabert, Eric Christian; Chierici, Roberto; Contardo, Didier; Della Negra, Rodolphe; Dupasquier, Thierry; Gelin, Georges; Giraud, Noël; Guillot, Gérard; Estre, Nicolas; Haroutunian, Roger; Lumb, Nicholas; Perries, Stephane; Schirra, Florent; Trocme, Benjamin; Vanzetto, Sylvain; Agram, Jean-Laurent; Blaes, Reiner; Drouhin, Frédéric; Ernenwein, Jean-Pierre; Fontaine, Jean-Charles; Berst, Jean-Daniel; Brom, Jean-Marie; Didierjean, Francois; Goerlach, Ulrich; Graehling, Philippe; Gross, Laurent; Hosselet, J; Juillot, Pierre; Lounis, Abdenour; Maazouzi, Chaker; Olivetto, Christian; Strub, Roger; Van Hove, Pierre; Anagnostou, Georgios; Brauer, Richard; Esser, Hans; Feld, Lutz; Karpinski, Waclaw; Klein, Katja; Kukulies, Christoph; Olzem, Jan; Ostapchuk, Andrey; Pandoulas, Demetrios; Pierschel, Gerhard; Raupach, Frank; Schael, Stefan; Schwering, Georg; Sprenger, Daniel; Thomas, Maarten; Weber, Markus; Wittmer, Bruno; Wlochal, Michael; Beissel, Franz; Bock, E; Flugge, G; Gillissen, C; Hermanns, Thomas; Heydhausen, Dirk; Jahn, Dieter; Kaussen, Gordon; Linn, Alexander; Perchalla, Lars; Poettgens, Michael; Pooth, Oliver; Stahl, Achim; Zoeller, Marc Henning; Buhmann, Peter; Butz, Erik; Flucke, Gero; Hamdorf, Richard Helmut; Hauk, Johannes; Klanner, Robert; Pein, Uwe; Schleper, Peter; Steinbruck, G; Blum, P; De Boer, Wim; Dierlamm, Alexander; Dirkes, Guido; Fahrer, Manuel; Frey, Martin; Furgeri, Alexander; Hartmann, Frank; Heier, Stefan; Hoffmann, Karl-Heinz; Kaminski, Jochen; Ledermann, Bernhard; Liamsuwan, Thiansin; Muller, S; Muller, Th; Schilling, Frank-Peter; Simonis, Hans-Jürgen; Steck, Pia; Zhukov, Valery; Cariola, P; De Robertis, Giuseppe; Ferorelli, Raffaele; Fiore, Luigi; Preda, M; Sala, Giuliano; Silvestris, Lucia; Tempesta, Paolo; Zito, Giuseppe; Creanza, Donato; De Filippis, Nicola; De Palma, Mauro; Giordano, Domenico; Maggi, Giorgio; Manna, Norman; My, Salvatore; Selvaggi, Giovanna; Albergo, Sebastiano; Chiorboli, Massimiliano; Costa, Salvatore; Galanti, Mario; Giudice, Nunzio; Guardone, Nunzio; Noto, Francesco; Potenza, Renato; Saizu, Mirela Angela; Sparti, V; Sutera, Concetta; Tricomi, Alessia; Tuve, Cristina; Brianzi, Mirko; Civinini, Carlo; Maletta, Fernando; Manolescu, Florentina; Meschini, Marco; Paoletti, Simone; Sguazzoni, Giacomo; Broccolo, B; Ciulli, Vitaliano; D'Alessandro, Raffaello; Focardi, Ettore; Frosali, Simone; Genta, Chiara; Landi, Gregorio; Lenzi, Piergiulio; Macchiolo, Anna; Magini, Nicolo; Parrini, Giuliano; Scarlini, Enrico; Cerati, Giuseppe Benedetto; Azzi, Patrizia; Bacchetta, Nicola; Candelori, Andrea; Dorigo, Tommaso; Kaminsky, A; Karaevski, S; Khomenkov, Volodymyr; Reznikov, Sergey; Tessaro, Mario; Bisello, Dario; De Mattia, Marco; Giubilato, Piero; Loreti, Maurizio; Mattiazzo, Serena; Nigro, Massimo; Paccagnella, Alessandro; Pantano, Devis; Pozzobon, Nicola; Tosi, Mia; Bilei, Gian Mario; Checcucci, Bruno; Fano, Livio; Servoli, Leonello; Ambroglini, Filippo; Babucci, Ezio; Benedetti, Daniele; Biasini, Maurizio; Caponeri, Benedetta; Covarelli, Roberto; Giorgi, Marco; Lariccia, Paolo; Mantovani, Giancarlo; Marcantonini, Marta; Postolache, Vasile; Santocchia, Attilio; Spiga, Daniele; Bagliesi, Giuseppe; Balestri, Gabriele; Berretta, Luca; Bianucci, S; Boccali, Tommaso; Bosi, Filippo; Bracci, Fabrizio; Castaldi, Rino; Ceccanti, Marco; Cecchi, Roberto; Cerri, Claudio; Cucoanes, Andi Sebastian; Dell'Orso, Roberto; Dobur, Didar; Dutta, Suchandra; Giassi, Alessandro; Giusti, Simone; Kartashov, Dmitry; Kraan, Aafke; Lomtadze, Teimuraz; Lungu, George-Adrian; Magazzu, Guido; Mammini, Paolo; Mariani, Filippo; Martinelli, Giovanni; Moggi, Andrea; Palla, Fabrizio; Palmonari, Francesco; Petragnani, Giulio; Profeti, Alessandro; Raffaelli, Fabrizio; Rizzi, Domenico; Sanguinetti, Giulio; Sarkar, Subir; Sentenac, Daniel; Serban, Alin Titus; Slav, Adrian; Soldani, A; Spagnolo, Paolo; Tenchini, Roberto; Tolaini, Sergio; Venturi, Andrea; Verdini, Piero Giorgio; Vos, Marcel; Zaccarelli, Luciano; Avanzini, Carlo; Basti, Andrea; Benucci, Leonardo; Bocci, Andrea; Cazzola, Ugo; Fiori, Francesco; Linari, Stefano; Massa, Maurizio; Messineo, Alberto; Segneri, Gabriele; Tonelli, Guido; Azzurri, Paolo; Bernardini, Jacopo; Borrello, Laura; Calzolari, Federico; Foa, Lorenzo; Gennai, Simone; Ligabue, Franco; Petrucciani, Giovanni; Rizzi, Andrea; Yang, Zong-Chang; Benotto, Franco; Demaria, Natale; Dumitrache, Floarea; Farano, R; Borgia, Maria Assunta; Castello, Roberto; Costa, Marco; Migliore, Ernesto; Romero, Alessandra; Abbaneo, Duccio; Abbas, M; Ahmed, Ijaz; Akhtar, I; Albert, Eric; Bloch, Christoph; Breuker, Horst; Butt, Shahid Aleem; Buchmuller, Oliver; Cattai, Ariella; Delaere, Christophe; Delattre, Michel; Edera, Laura Maria; Engstrom, Pauli; Eppard, Michael; Gateau, Maryline; Gill, Karl; Giolo-Nicollerat, Anne-Sylvie; Grabit, Robert; Honma, Alan; Huhtinen, Mika; Kloukinas, Kostas; Kortesmaa, Jarmo; Kottelat, Luc-Joseph; Kuronen, Auli; Leonardo, Nuno; Ljuslin, Christer; Mannelli, Marcello; Masetti, Lorenzo; Marchioro, Alessandro; Mersi, Stefano; Michal, Sebastien; Mirabito, Laurent; Muffat-Joly, Jeannine; Onnela, Antti; Paillard, Christian; Pal, Imre; Pernot, Jean-Francois; Petagna, Paolo; Petit, Patrick; Piccut, C; Pioppi, Michele; Postema, Hans; Ranieri, Riccardo; Ricci, Daniel; Rolandi, Gigi; Ronga, Frederic Jean; Sigaud, Christophe; Syed, A; Siegrist, Patrice; Tropea, Paola; Troska, Jan; Tsirou, Andromachi; Vander Donckt, Muriel; Vasey, François; Alagoz, Enver; Amsler, Claude; Chiochia, Vincenzo; Regenfus, Christian; Robmann, Peter; Rochet, Jacky; Rommerskirchen, Tanja; Schmidt, Alexander; Steiner, Stefan; Wilke, Lotte; Church, Ivan; Cole, Joanne; Coughlan, John A; Gay, Arnaud; Taghavi, S; Tomalin, Ian R; Bainbridge, Robert; Cripps, Nicholas; Fulcher, Jonathan; Hall, Geoffrey; Noy, Matthew; Pesaresi, Mark; Radicci, Valeria; Raymond, David Mark; Sharp, Peter; Stoye, Markus; Wingham, Matthew; Zorba, Osman; Goitom, Israel; Hobson, Peter R; Reid, Ivan; Teodorescu, Liliana; Hanson, Gail; Jeng, Geng-Yuan; Liu, Haidong; Pasztor, Gabriella; Satpathy, Asish; Stringer, Robert; Mangano, Boris; Affolder, K; Affolder, T; Allen, Andrea; Barge, Derek; Burke, Samuel; Callahan, D; Campagnari, Claudio; Crook, A; D'Alfonso, Mariarosaria; Dietch, J; Garberson, Jeffrey; Hale, David; Incandela, H; Incandela, Joe; Jaditz, Stephen; Kalavase, Puneeth; Kreyer, Steven Lawrence; Kyre, Susanne; Lamb, James; Mc Guinness, C; Mills, C; Nguyen, Harold; Nikolic, Milan; Lowette, Steven; Rebassoo, Finn; Ribnik, Jacob; Richman, Jeffrey; Rubinstein, Noah; Sanhueza, S; Shah, Yousaf Syed; Simms, L; Staszak, D; Stoner, J; Stuart, David; Swain, Sanjay Kumar; Vlimant, Jean-Roch; White, Dean; Ulmer, Keith; Wagner, Stephen Robert; Bagby, Linda; Bhat, Pushpalatha C; Burkett, Kevin; Cihangir, Selcuk; Gutsche, Oliver; Jensen, Hans; Johnson, Mark; Luzhetskiy, Nikolay; Mason, David; Miao, Ting; Moccia, Stefano; Noeding, Carsten; Ronzhin, Anatoly; Skup, Ewa; Spalding, William J; Spiegel, Leonard; Tkaczyk, Slawek; Yumiceva, Francisco; Zatserklyaniy, Andriy; Zerev, E; Anghel, Ioana Maria; Bazterra, Victor Eduardo; Gerber, Cecilia Elena; Khalatian, S; Shabalina, Elizaveta; Baringer, Philip; Bean, Alice; Chen, Jie; Hinchey, Carl Louis; Martin, Christophe; Moulik, Tania; Robinson, Richard; Gritsan, Andrei; Lae, Chung Khim; Tran, Nhan Viet; Everaerts, Pieter; Hahn, Kristan Allan; Harris, Philip; Nahn, Steve; Rudolph, Matthew; Sung, Kevin; Betchart, Burton; Demina, Regina; Gotra, Yury; Korjenevski, Sergey; Miner, Daniel Carl; Orbaker, Douglas; Christofek, Leonard; Hooper, Ryan; Landsberg, Greg; Nguyen, Duong; Narain, Meenakshi; Speer, Thomas; Tsang, Ka Vang

    2009-01-01

    In March 2007 the assembly of the Silicon Strip Tracker was completed at the Tracker Integration Facility at CERN. Nearly 15% of the detector was instrumented using cables, fiber optics, power supplies, and electronics intended for the operation at the LHC. A local chiller was used to circulate the coolant for low temperature operation. In order to understand the efficiency and alignment of the strip tracker modules, a cosmic ray trigger was implemented. From March through July 4.5 million triggers were recorded. This period, referred to as the Sector Test, provided practical experience with the operation of the Tracker, especially safety, data acquisition, power, and cooling systems. This paper describes the performance of the strip system during the Sector Test, which consisted of five distinct periods defined by the coolant temperature. Significant emphasis is placed on comparisons between the data and results from Monte Carlo studies.

  19. Nonlinear Vibration Analysis of Moving Strip with Inertial Boundary Condition

    Directory of Open Access Journals (Sweden)

    Chong-yi Gao

    2015-01-01

    Full Text Available According to the movement mechanism of strip and rollers in tandem mill, the strip between two stands was simplified to axially moving Euler beam and the rollers were simplified to the inertial component on the fixed axis rotation, namely, inertial boundary. Nonlinear vibration mechanical model of Euler beam with inertial boundary conditions was established. The transverse and longitudinal motion equations were derived based on Hamilton’s principle. Kantorovich averaging method was employed to discretize the motion equations and the inertial boundary equations, and the solutions were obtained using the modified iteration method. Depending on numerical calculation, the amplitude-frequency responses of Euler beam were determined. The axial velocity, tension, and rotational inertia have strong influences on the vibration characteristics. The results would provide an important theoretical reference to control and analyze the vertical vibration of moving strip in continuous rolling process.

  20. ISM stripping from cluster galaxies and inhomogeneities in cooling flows

    Science.gov (United States)

    Soker, Noam; Bregman, Joel N.; Sarazin, Craig L.

    1990-01-01

    Analyses of the x ray surface brightness profiles of cluster cooling flows suggest that the mass flow rate decreases towards the center of the cluster. It is often suggested that this decrease results from thermal instabilities, in which denser blobs of gas cool rapidly and drop below x ray emitting temperatures. If the seeds for the thermal instabilities are entropy perturbations, these perturbations must enter the flow already in the nonlinear regime. Otherwise, the blobs would take too long to cool. Here, researchers suggest that such nonlinear perturbations might start as blobs of interstellar gas which are stripped out of cluster galaxies. Assuming that most of the gas produced by stellar mass loss in cluster galaxies is stripped from the galaxies, the total rate of such stripping is roughly M sub Interstellar Matter (ISM) approx. 100 solar mass yr(-1). It is interesting that the typical rates of cooling in cluster cooling flows are M sub cool approx. 100 solar mass yr(-1). Thus, it is possible that a substantial portion of the cooling gas originates as blobs of interstellar gas stripped from galaxies. The magnetic fields within and outside of the low entropy perturbations can help to maintain their identities, both by suppressing thermal conduction and through the dynamical effects of magnetic tension. One significant question concerning this scenario is: Why are cooling flows seen only in a fraction of clusters, although one would expect gas stripping to be very common. It may be that the density perturbations only survive and cool efficiently in clusters with a very high intracluster gas density and with the focusing effect of a central dominant galaxy. Inhomogeneities in the intracluster medium caused by the stripping of interstellar gas from galaxies can have a number of other effects on clusters. For example, these density fluctuations may disrupt the propagation of radio jets through the intracluster gas, and this may be one mechanism for producing Wide

  1. Silicon strip detector qualification for the CMS experiment

    International Nuclear Information System (INIS)

    Kaussen, Gordon

    2008-01-01

    To provide the best spatial resolution for the particle trajectory reconstruction and a very fast readout, the inner tracking system of CMS is build up of silicon detectors with a pixel tracker in the center surrounded by a strip tracker. The silicon strip tracker consists of so-called modules representing the smallest detection unit of the tracking device. These modules are mounted on higher-level structures called shells in the tracker inner barrel (TIB), rods in the tracker outer barrel (TOB), disks in the tracker inner disks (TID) and petals in the tracker end caps (TEC). The performance of the participating two shells of the TIB, four rods of the TOB and two petals of the TEC (representing about 1% of the final strip tracker) could be studied in different magnetic fields over a period of approximately two month using cosmic muon signals. The last test before inserting the tracker in the CMS experiment was the Tracker Slice Test performed in spring/summer 2007 at the Tracker Integration Facility (TIF) at CERN after installing all subdetectors in the tracker support tube. Approximately 25% of the strip tracker +z side was powered and read out using a cosmic ray trigger built up of scintillation counters. In total, about 5 million muon events were recorded under various operating conditions. These events together with results from commissioning runs were used to study the detector response like cluster charges, signal-to-noise ratios and single strip noise behaviour as well as to identify faulty channels which turned out to be in the order of a few per mille. The performance of the silicon strip tracker during these different construction stages is discussed in this thesis with a special emphasis on the tracker end caps. (orig.)

  2. Experimental evidence that wildflower strips increase pollinator visits to crops.

    Science.gov (United States)

    Feltham, Hannah; Park, Kirsty; Minderman, Jeroen; Goulson, Dave

    2015-08-01

    Wild bees provide a free and potentially diverse ecosystem service to farmers growing pollination-dependent crops. While many crops benefit from insect pollination, soft fruit crops, including strawberries are highly dependent on this ecosystem service to produce viable fruit. However, as a result of intensive farming practices and declining pollinator populations, farmers are increasingly turning to commercially reared bees to ensure that crops are adequately pollinated throughout the season. Wildflower strips are a commonly used measure aimed at the conservation of wild pollinators. It has been suggested that commercial crops may also benefit from the presence of noncrop flowers; however, the efficacy and economic benefits of sowing flower strips for crops remain relatively unstudied. In a study system that utilizes both wild and commercial pollinators, we test whether wildflower strips increase the number of visits to adjacent commercial strawberry crops by pollinating insects. We quantified this by experimentally sowing wildflower strips approximately 20 meters away from the crop and recording the number of pollinator visits to crops with, and without, flower strips. Between June and August 2013, we walked 292 crop transects at six farms in Scotland, recording a total of 2826 pollinators. On average, the frequency of pollinator visits was 25% higher for crops with adjacent flower strips compared to those without, with a combination of wild and commercial bumblebees (Bombus spp.) accounting for 67% of all pollinators observed. This effect was independent of other confounding effects, such as the number of flowers on the crop, date, and temperature. Synthesis and applications. This study provides evidence that soft fruit farmers can increase the number of pollinators that visit their crops by sowing inexpensive flower seed mixes nearby. By investing in this management option, farmers have the potential to increase and sustain pollinator populations over time.

  3. Silicon strip detector qualification for the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kaussen, Gordon

    2008-10-06

    To provide the best spatial resolution for the particle trajectory reconstruction and a very fast readout, the inner tracking system of CMS is build up of silicon detectors with a pixel tracker in the center surrounded by a strip tracker. The silicon strip tracker consists of so-called modules representing the smallest detection unit of the tracking device. These modules are mounted on higher-level structures called shells in the tracker inner barrel (TIB), rods in the tracker outer barrel (TOB), disks in the tracker inner disks (TID) and petals in the tracker end caps (TEC). The performance of the participating two shells of the TIB, four rods of the TOB and two petals of the TEC (representing about 1% of the final strip tracker) could be studied in different magnetic fields over a period of approximately two month using cosmic muon signals. The last test before inserting the tracker in the CMS experiment was the Tracker Slice Test performed in spring/summer 2007 at the Tracker Integration Facility (TIF) at CERN after installing all subdetectors in the tracker support tube. Approximately 25% of the strip tracker +z side was powered and read out using a cosmic ray trigger built up of scintillation counters. In total, about 5 million muon events were recorded under various operating conditions. These events together with results from commissioning runs were used to study the detector response like cluster charges, signal-to-noise ratios and single strip noise behaviour as well as to identify faulty channels which turned out to be in the order of a few per mille. The performance of the silicon strip tracker during these different construction stages is discussed in this thesis with a special emphasis on the tracker end caps. (orig.)

  4. A visual strip sensor for determination of iron

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Sanjukta A., E-mail: sanjuktaak301@gmail.com [Analytical Chemistry Division, BARC, Trombay, Mumbai 400085 (India); Thakur, Neha; Parab, Harshala J.; Pandey, Shailaja P. [Analytical Chemistry Division, BARC, Trombay, Mumbai 400085 (India); Shinde, Rakesh N.; Pandey, Ashok K. [Radiochemistry Division, BARC, Trombay, Mumbai 400085 (India); Kumar, Sangita D.; Reddy, A.V.R. [Analytical Chemistry Division, BARC, Trombay, Mumbai 400085 (India)

    2014-12-03

    Highlights: • A visual strip sensor for on-site detection of iron has been developed and made. • The sensor is easy to synthesize, portable and recyclable with shelf life >1 year. • Visual detection limit for iron using the present sensor is 50 ng mL{sup −1}. • Visual strip sensor was applied to ground water and fruit juices. - Abstract: A visual strip has been developed for sensing iron in different aqueous samples like natural water and fruit juices. The sensor has been synthesized by UV-radiation induced graft polymerization of acrylamide monomer in microporous poly(propylene) base. For physical immobilization of iron selective reagent, the in situ polymerization of acrylamide has been carried out in the presence of 1,10-phenanthroline. The loaded strip on interaction with Fe(II) in aqueous solution turned into orange red color and the intensity of the color was found to be directly proportional to the amount of Fe(II) in the aqueous sample. The minimal sensor response with naked eye was found for 50 ng mL{sup −1} of Fe in 15 min of interaction. However, as low as 20 ng mL{sup −1} Fe could be quantified using a spectrophotometer. The detection limit calculated using the 3s/S criteria, where ‘s’ is the standard deviation of the absorbance of blank reagent loaded strip and ‘S’ is the slope of the linear calibration plot, was 1.0 ng mL{sup −1}. The strip was applied to measure Fe in a variety of samples such as ground water and fruit juices.

  5. Leukocytes Breach Endothelial Barriers by Insertion of Nuclear Lobes and Disassembly of Endothelial Actin Filaments

    Directory of Open Access Journals (Sweden)

    Sagi Barzilai

    2017-01-01

    Full Text Available The endothelial cytoskeleton is a barrier for leukocyte transendothelial migration (TEM. Mononuclear and polymorphonuclear leukocytes generate gaps of similar micron-scale size when squeezing through inflamed endothelial barriers in vitro and in vivo. To elucidate how leukocytes squeeze through these barriers, we co-tracked the endothelial actin filaments and leukocyte nuclei in real time. Nuclear squeezing involved either preexistent or de novo-generated lobes inserted into the leukocyte lamellipodia. Leukocyte nuclei reversibly bent the endothelial actin stress fibers. Surprisingly, formation of both paracellular gaps and transcellular pores by squeezing leukocytes did not require Rho kinase or myosin II-mediated endothelial contractility. Electron-microscopic analysis suggested that nuclear squeezing displaced without condensing the endothelial actin filaments. Blocking endothelial actin turnover abolished leukocyte nuclear squeezing, whereas increasing actin filament density did not. We propose that leukocyte nuclei must disassemble the thin endothelial actin filaments interlaced between endothelial stress fibers in order to complete TEM.

  6. Mitochondria, endothelial cell function, and vascular diseases.

    Science.gov (United States)

    Tang, Xiaoqiang; Luo, Yu-Xuan; Chen, Hou-Zao; Liu, De-Pei

    2014-01-01

    Mitochondria are perhaps the most sophisticated and dynamic responsive sensing systems in eukaryotic cells. The role of mitochondria goes beyond their capacity to create molecular fuel and includes the generation of reactive oxygen species, the regulation of calcium, and the activation of cell death. In endothelial cells, mitochondria have a profound impact on cellular function under both healthy and diseased conditions. In this review, we summarize the basic functions of mitochondria in endothelial cells and discuss the roles of mitochondria in endothelial dysfunction and vascular diseases, including atherosclerosis, diabetic vascular dysfunction, pulmonary artery hypertension, and hypertension. Finally, the potential therapeutic strategies to improve mitochondrial function in endothelial cells and vascular diseases are also discussed, with a focus on mitochondrial-targeted antioxidants and calorie restriction.

  7. Mitochondria, Endothelial Cell Function and Vascular Diseases

    Directory of Open Access Journals (Sweden)

    Xiaoqiang eTang

    2014-05-01

    Full Text Available Mitochondria are perhaps the most sophisticated and dynamic responsive sensing systems in eukaryotic cells. The role of mitochondria goes beyond their capacity to create molecular fuel and includes the generation of reactive oxygen species, the regulation of calcium, and the activation of cell death. In endothelial cells, mitochondria have a profound impact on cellular function under both healthy and diseased conditions. In this review, we summarize the basic functions of mitochondria in endothelial cells and discuss the roles of mitochondria in endothelial dysfunction and vascular diseases, including atherosclerosis, diabetic vascular dysfunction, pulmonary artery hypertension and hypertension. Finally, the potential therapeutic strategies to improve mitochondrial function in endothelial cells and vascular diseases are also discussed, with a focus on mitochondrial-targeted antioxidants and calorie restriction.

  8. A plane mirror experiment inspired by a comic strip

    Science.gov (United States)

    Lúcio Prados Ribeiro, Jair

    2016-01-01

    A comic strip about a plane mirror was used in a high school optics test, and it was perceived that a large portion of the students believed that the mirror should be larger than the object so the virtual image could be entirely visible. Inspired on the comic strip, an experimental demonstration with flat mirrors was developed, in order to readdress this topic learning. Students were encouraged to create their own investigation of the phenomenon with a simple instrumental apparatus and also suggest different experimental approaches.

  9. The CMS Silicon Strip Tracker performance using cosmic ray data

    CERN Document Server

    Borrello, L

    2010-01-01

    The CMS Silicon Strip Tracker is the largest tracking system based on silicon detector technology ever built for high energy physics experiment. It consists of 24,244 single-sided micro-strip sensors for a total active area of 198 $m^2$ and about 10 million readout channels. The SST was installed inside CMS in December 2007, commissioned during summer 2008 and then it participated along with other CMS subdetectors in several cosmic muon data taking runs. The commissioning strategy, operational experience and detector performance results will be presented.

  10. Stability of flow over plates with porous suction strips

    Science.gov (United States)

    Reed, H. L.; Nayfeh, A. H.

    1981-01-01

    This paper addresses the stability of two-dimensional, incompressible boundary-layer flow over plates with suction through porous strips. The mean flow is calculated using linearized triple-deck, closed-form solutions. The stability results of the triple-deck theory are shown to be in good agreement with those of the interacting boundary layers. Then different configurations of number, spacing, and mass flow rate through such porous strips are analyzed and compared with nonsimilar uniform-suction stability results from the point of view of applicability to laminar flow control.

  11. The Las Vegas Strip as a Genuinely Invented Global Landscape

    Directory of Open Access Journals (Sweden)

    Daniel Ortega

    2004-12-01

    Full Text Available Las Vegas, Nevada, is typically recognised as a place via a single urban gesture, that gesture being Las Vegas Boulevard, which is more commonly referred to as "The Strip". In constructing a thesis around the theme, "Here or There? Interconnections between the Global and the Local", one cannot ignore the invitation to discuss globalisation and its effects on a particular local fabric. For the purpose of this text, globalisation can be thought of as what Carmona et al describe as an intricate series of events leading to the world "becoming increasingly interconnected, with centralised decision making exploiting economies of scale and standardisation" (2003: 101. The centralised decision-making process for The Strip is evident in the strategy to develop individually themed casino resorts along Las Vegas Boulevard that respond to a competitive economy, thus creating a newly standardised landscape. If we also understand that globalisation can be thought of as the development of an interconnected world where economic, political and cultural boundaries can be easily crossed, this work can begin to define how the Las Vegas Strip is a genuinely invented global landscape. This paper addresses the "here-ness" as well as the "there-ness" of The Strip, while offering a dialectical framework for establishing a meaning of place by having 'there' placed 'here'. By employing semiological interpretations of real landscapes from around the globe (for example, Venturi et al, 1972, The Strip becomes a newly invented landscape of "simulations" (Baudrillard, 1988. As such, The Strip acts as a narrative that forms a unique place, opening the door to questions of authenticity and identity. This paper concludes by focusing on the question of "Here or There?" as an appropriate deviation from the assumed role that the post-modern landscape of the Las Vegas Strip plays. This work is intended to be a point of departure from the frequent criticism of the Las Vegas Strip as

  12. Beam test of CSES silicon strip detector module

    Science.gov (United States)

    Zhang, Da-Li; Lu, Hong; Wang, Huan-Yu; Li, Xin-Qiao; Xu, Yan-Bing; An, Zheng-Hua; Yu, Xiao-xia; Wang, Hui; Shi, Feng; Wang, Ping; Zhao, Xiao-Yun

    2017-05-01

    The silicon-strip tracker of the China Seismo-Electromagnetic Satellite (CSES) consists of two double-sided silicon strip detectors (DSSDs) which provide incident particle tracking information. A low-noise analog ASIC VA140 was used in this study for DSSD signal readout. A beam test on the DSSD module was performed at the Beijing Test Beam Facility of the Beijing Electron Positron Collider (BEPC) using a 400-800 MeV/c proton beam. The pedestal analysis results, RMSE noise, gain correction, and intensity distribution of incident particles of the DSSD module are presented. Supported by the XXX Civil Space Programme

  13. Type 2 Diabetes: Endothelial dysfunction and Exercise

    OpenAIRE

    Hwang, Moon-Hyon; Kim, Sangho

    2014-01-01

    [Purpose] Vascular endothelial dysfunction is an early marker of atherosclerosis characterized by decreased nitric oxide bioavailability in the vascular endothelium and smooth muscle cells. Recently, some animal models and in vitro trials demonstrated that excessive superoxide production from mitochondria within vascular endothelial cells played a role in the pathogenesis of atherosclerosis in type 2 diabetes. This review provides a systematic assessment of the effectiveness of exercise to id...

  14. Young tourists visiting strip clubs and paying for sex

    DEFF Research Database (Denmark)

    Hesse, Morten; Tutenges, Sébastien

    2011-01-01

    it for the first time. Among the men who attended strip clubs, 32% reported having done it for the first time. Stripclub patronage and paying for sex were both associated with higher levels of drinking, use of Viagra, and with having done the same thing before the holiday. Paying for sex was uniquely associated...

  15. Beam tests of ATLAS SCT silicon strip detector modules

    Czech Academy of Sciences Publication Activity Database

    Campabadal, F.; Fleta, C.; Key, M.; Böhm, Jan; Mikeštíková, Marcela; Šťastný, Jan

    2005-01-01

    Roč. 538, - (2005), s. 384-407 ISSN 0168-9002 R&D Projects: GA MŠk(CZ) 1P04LA212 Institutional research plan: CEZ:AV0Z10100502 Keywords : ATLAS * silicon * micro-strip * beam * test Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.224, year: 2005

  16. Anodic Stripping Voltammetry for Arsenic Determination on Composite Gold Electrode

    Czech Academy of Sciences Publication Activity Database

    Navrátil, Tomáš; Kopanica, M.; Krista, J.

    2003-01-01

    Roč. 48, č. 2 (2003), s. 265-272 ISSN 0009-2223 Grant - others:GIT(AR) 101/02/U111/CZ Institutional research plan: CEZ:AV0Z4040901 Keywords : arsenic determination * stripping voltammetry * composite gold electrode Subject RIV: CG - Electrochemistry Impact factor: 0.415, year: 2003

  17. Visual method for detecting critical damage in railway contact strips

    Science.gov (United States)

    Judek, S.; Skibicki, J.

    2018-05-01

    Ensuring an uninterrupted supply of power in the electric traction is vital for the safety of this important transport system. For this purpose, monitoring and diagnostics of the technical condition of the vehicle’s power supply elements are becoming increasingly common. This paper presents a new visual method for detecting contact strip damage, based on measurement and analysis of the movement of the overhead contact line (OCL) wire. A measurement system configuration with a 2D camera was proposed. The experimental method has shown that contact strips damage can be detected by transverse displacement signal analysis. It has been proven that the velocity signal numerically established on that basis has a comparable level in the case of identical damage, regardless of its location on the surface of the contact strip. The proposed method belongs to the group of contact-less measurements, so it does not require interference with the structure of the catenary network nor the mounting of sensors in its vicinity. Measurement of displacements of the contact wire in 2D space makes it possible to combine the functions of existing diagnostic stands assessing the correctness of the mean contact force control adjustment of the current collector with the elements of the contact strip diagnostics, which involves detecting their damage which may result in overhead contact line rupture.

  18. Nutrient removal by prairie filter strips in agricultural landscapes

    Science.gov (United States)

    X. Zhou; M.J. Helmers; H. Asbjornsen; R. Kolka; M.D. Tomer; R.M. Cruse

    2014-01-01

    Nitrogen (N) and phosphorus (P) from agricultural landscapes have been identified as primary sources of excess nutrients in aquatic systems. The main objective of this study was to evaluate the effectiveness of prairie filter strips (PFS) in removing nutrients from cropland runoff in 12 small watersheds in central Iowa. Four treatments with PFS of different spatial...

  19. Metallurgical analysis of spalled work roll of hot strip mill

    International Nuclear Information System (INIS)

    Khan, M.M.; Khan, M.A.

    1993-01-01

    In this study failure analysis of four work roll of the Hot Strip Mill is carried out. The microstructure is correlated with the chemical composition of shell and roll-life. It was concluded that for the longer service of the roll, cementite, graphite and martensite should be balanced (as per working requirement of the mill). (author)

  20. Effectiveness of anti-strip agents in asphalt mixtures.

    Science.gov (United States)

    2012-07-01

    Since the late 1970s there has been much research performed to better understand the stripping phenomenon in asphalt mixtures. : As a result, there have been changes in both materials and technology over the past 30 years to improve the resistance to...

  1. Strip-Search Case Testing Balance between Privacy, Student Safety

    Science.gov (United States)

    Robelen, Erik W.

    2009-01-01

    As it weighs the high-profile case of a 13-year-old girl strip-searched at school, the U.S. Supreme Court is grappling with where to draw the line between protecting student privacy rights and allowing school officials to take steps to ensure a safe environment. During oral arguments, several of the justices seemed sympathetic to the challenges…

  2. Evaluation of Questionnaire, Reagent Strip and Egg Count as ...

    African Journals Online (AJOL)

    A longitudinal study covering 55 months evaluated the three diagnostic tools used for confirmation of prevalence of urinary schistosomiasis among 1151 consented primary school pupils in 13 communities of Edo State, Nigeria. Questionnaire, reagent strip method and parasitological examination were employed.

  3. Qualification of submerged-arc narrow strip cladding process

    International Nuclear Information System (INIS)

    Ayres, P.S.; Gottschling, J.D.; Jeffers, G.K.

    1975-08-01

    An unique narrow strip cladding process for use on both plate and forging material for nuclear components was developed. The qualification testing of this low-heat input process for cladding nuclear components, including those of SA508 Class 2 material is described. The theory that explains the acceptable results of these tests is also given. (auth)

  4. Qualification of submerged-arc narrow strip cladding process

    International Nuclear Information System (INIS)

    Ayres, P.S.; Gottschling, J.D.; Jeffers, G.K.

    1976-03-01

    Babcock and Wilcox has developed an unique narrow strip cladding process for use on both plate and forging material for nuclear components. The qualification testing of this low-heat input process for cladding nuclear components is described, including those of SA508 Class 2 material. The theory that explains the acceptable results of these tests is also given

  5. Effectiveness of buffer strips in the Netherlands : research plan

    NARCIS (Netherlands)

    Noij, G.J.

    2006-01-01

    On 1 July 2004 the European Commission and the Netherlands reached an agreement about the implementation of the Nitrates Directive for the nearby future. In this decree narrow fertilizer-free strips of 0.25 – 1.501 m are prescribed, depending on the type of crop and the method of herbicide

  6. Digital Images of Breast Biopsies using a Silicon Strip Detector

    International Nuclear Information System (INIS)

    Montano, Luis M.; Diaz, Claudia C.; Leyva, Antonio; Cabal, Fatima; Ortiz, Carlos M.

    2006-01-01

    In our study we have used a silicon strip detector to obtain digital images of some breast tissues with micro calcifications. Some of those images will be shown and we will discuss the perspectives of using this technique as an improvement of breast cancer diagnostics

  7. Magnetic stray fields of periodically arranged Co-Crmicro strips

    NARCIS (Netherlands)

    te Lintelo, J.G.T.; te Lintelo, J.G.T.

    1993-01-01

    Research was carried out on magnetic stray fields of Co-Cr micro strips. This investigation was motivated by the search for increasing bit density and miniaturisation in magnetic data storage and magnetic sensor devices. In these devices the magnetisation is patterned, i.e. by writing bits or

  8. Results of Laboratory Testing of Advanced Power Strips

    Energy Technology Data Exchange (ETDEWEB)

    Earle, L. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sparn, B. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2012-08-01

    Presented at the ACEEE Summer Study on Energy Efficiency in Buildings on August 12-17, 2012, this presentation reports on laboratory tests of 20 currently available advanced power strip products, which reduce wasteful electricity use of miscellaneous electric loads in buildings.

  9. Impact of radiation on breakdown performance of Si strip detectors

    CERN Document Server

    Bhardwaj, A; Chatterji, S; Ranjan, Kirti; Shivpuri, E K; Srivastava-Ajay, K

    2002-01-01

    The very intense radiation environment of high luminosity future colliding beam experiments, like Large Hadron Collider (LHC etc.) makes radiation hardness the most urgent demand for Si detectors. The radiation hardness of Si strip detectors especially developed for LHC experiment was investigated with respect to ionizing and nonionizing radiation using computer simulations. (10 refs).

  10. Consideration of Factors Affecting Strip Effluent PH and Sodium Content

    Energy Technology Data Exchange (ETDEWEB)

    Peters, T. [Savannah River Site (SRS), Aiken, SC (United States)

    2015-07-29

    A number of factors were investigated to determine possible reasons for why the Strip Effluent (SE) can sometimes have higher than expected pH values and/or sodium content, both of which have prescribed limits. All of the factors likely have some impact on the pH values and Na content.

  11. Mechanistic modeling & effectiveness of buffer strips for pesticide regulatory frameworks

    Science.gov (United States)

    Vegetative Filter Strips (VFS) have been used as an effective conservation practice in agricultural areas for controlling and mitigate the effect of sediment, nutrients and pesticides loads into water bodies. In addition to the agricultural sector, another important use of VFS for controlling plague...

  12. Adsorptive stripping voltammetric methods for determination of aripiprazole

    Directory of Open Access Journals (Sweden)

    Derya Aşangil

    2012-06-01

    Full Text Available Anodic behavior of aripiprazole (ARP was studied using electrochemical methods. Charge transfer, diffusion and surface coverage coefficients of adsorbed molecules and the number of electrons transferred in electrode mechanisms were calculated for quasi-reversible and adsorption-controlled electrochemical oxidation of ARP at 1.15 V versus Ag/AgCl at pH 4.0 in Britton–Robinson buffer (BR on glassy carbon electrode. Voltammetric methods for direct determination of ARP in pharmaceutical dosage forms and biological samples were developed. Linearity range is found as from 11.4 μM (5.11 mg/L to 157 μM (70.41 mg/L without stripping mode and it is found as from 0.221 μM (0.10 mg/L to 13.6 μM (6.10 mg/L with stripping mode. Limit of detection (LOD was found to be 0.11 μM (0.05 mg/L in stripping voltammetry. Methods were successfully applied to assay the drug in tablets, human serum and human urine with good recoveries between 95.0% and 104.6% with relative standard deviation less than 10%. Keywords: Adsorptive stripping voltammetry, Aripiprazole, Electrochemical behavior, Human serum and urine, Pharmaceuticals

  13. Development of the H1 backward silicon strip detector

    International Nuclear Information System (INIS)

    Eick, W.; Hansen, K.; Lange, W.; Prell, S.; Zimmermann, W.; Bullough, M.A.; Greenwood, N.M.; Lucas, A.D.; Newton, A.M.; Wilburn, C.D.; Horisberger, R.; Pitzl, D.; Haynes, W.J.; Noyes, G.

    1996-10-01

    The development and first results are described of a silicon strip detector telescope for the HERA experiment H1 designed to measure the polar angle of deep inelastic scattered electrons at small Bjorken x and low momentum transfers Q 2 . (orig.)

  14. Engineering analyses of large precision cathode strip chambers for GEM

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, J.A.; Belser, F.C.; Pratuch, S.M.; Wuest, C.R. [Lawrence Livermore National Lab., CA (United States); Mitselmakher, G. [Superconducting Super Collider Lab., Dallas, TX (United States); Gordeev, A. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Johnson, C.V. [Lawrence Livermore National Lab., CA (United States)]|[Superconducting Super Collider Lab., Dallas, TX (United States); Polychronakos, V.A. [Brookhaven National Lab., Upton, NY (United States); Golutvin, I.A. [Joint Institute for Nuclear Research, Dubna (Russian Federation)

    1993-10-21

    Structural analyses of large precision cathode strip chambers performed up to the date of this publication are documented. Mechanical property data for typical chamber materials are included. This information, originally intended to be an appendix to the {open_quotes}CSC Structural Design Bible,{close_quotes} is presented as a guide for future designers of large chambers.

  15. Vibration control of an elastic strip by a singular force

    Indian Academy of Sciences (India)

    MS received 10 September 2008; revised 27 August 2009; accepted 17 December. 2009. Abstract. Vibration characteristics of an elastic plate in the shape of an infinite strip are changed by applying a lateral concentrated force to the plate. The homo- geneous, isotropic, elastic plate is infinite in the x-direction and the sides ...

  16. Vibration control of an elastic strip by a singular force

    Indian Academy of Sciences (India)

    Vibration characteristics of an elastic plate in the shape of an infinite strip are changed by applying a lateral concentrated force to the plate. The homogeneous, isotropic, elastic plate is infinite in the -direction and the sides are simply supported. The size of the force is changed in proportion to the displacement measured at ...

  17. Low material budget floating strip Micromegas for ion transmission radiography

    Energy Technology Data Exchange (ETDEWEB)

    Bortfeldt, J., E-mail: jonathan.bortfeldt@cern.ch [LMU Munich, LS Schaile, Am Coulombwall 1, D-85748 Garching (Germany); Biebel, O.; Flierl, B.; Hertenberger, R.; Klitzner, F.; Lösel, Ph. [LMU Munich, LS Schaile, Am Coulombwall 1, D-85748 Garching (Germany); Magallanes, L. [LMU Munich, LS Parodi, Am Coulombwall 1, D-85748 Garching (Germany); University Hospital Heidelberg, Im Neuenheimer Feld 672, D-69120 Heidelberg (Germany); Müller, R. [LMU Munich, LS Schaile, Am Coulombwall 1, D-85748 Garching (Germany); Parodi, K. [LMU Munich, LS Parodi, Am Coulombwall 1, D-85748 Garching (Germany); Heidelberg Ion-Beam Therapy Center, Im Neuenheimer Feld 450, D-69120 Heidelberg (Germany); Schlüter, T. [LMU Munich, Excellence Cluster Universe, Boltzmannstr. 2, D-85748 Garching (Germany); Voss, B. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstr. 1, D-64291 Darmstadt (Germany); Zibell, A. [JMU Würzburg, Sanderring 2, D-97070 Würzburg (Germany)

    2017-02-11

    Floating strip Micromegas are high-accuracy and discharge insensitive gaseous detectors, able to track single particles at fluxes of 7 MHz/cm{sup 2} with 100 μm resolution. We developed low-material-budget detectors with one-dimensional strip readout, suitable for tracking at highest particle rates as encountered in medical ion transmission radiography or inner tracker applications. Recently we additionally developed Kapton-based floating strip Micromegas with two-dimensional strip readout, featuring an overall thickness of 0.011 X{sub 0}. These detectors were tested in high-rate proton and carbon-ion beams at the tandem accelerator in Garching and the Heidelberg Ion-Beam Therapy Center, operated with an optimized Ne:CF{sub 4} gas mixture. By coupling the Micromegas detectors to a new scintillator based range detector, ion transmission radiographies of PMMA and tissue-equivalent phantoms were acquired. The range detector with 18 layers is read out via wavelength shifting fibers, coupled to a multi-anode photomultiplier. We present the performance of the Micromegas detectors with respect to timing and single plane track reconstruction using the μTPC method. We discuss the range resolution of the scintillator range telescope and present the image reconstruction capabilities of the combined system.

  18. Paint stripping with high power flattened Gaussian beams

    CSIR Research Space (South Africa)

    Forbes, A

    2009-08-01

    Full Text Available In this paper the researchers present results on improved paint stripping performance with an intra-cavity generated Flattened Gaussian Beam (FGB). A resonator with suitable diffractive optical elements was designed in order to produce a single mode...

  19. Upconversion fluorescent strip sensor for rapid determination of Vibrio anguillarum

    Science.gov (United States)

    Zhao, Peng; Wu, Yuanyuan; Zhu, Yihua; Yang, Xiaoling; Jiang, Xin; Xiao, Jingfan; Zhang, Yuanxing; Li, Chunzhong

    2014-03-01

    Here, we report a simple and ultrasensitive upconversion fluorescent strip sensor based on NaYF4:Yb,Er nanoparticles (NPs) and the lateral flow immunochromatographic assay (LFIA). Carboxyl-modified β-NaYF4:Yb,Er NPs were successfully synthesized by a facile one-pot solvothermal approach, upon further coupling with monoclonal antibody, the resultant UCNPs-antibody conjugates probes were used in LFIA and served as signal vehicles for the fluorescent reporters. V. anguillarum was used as a model analyte to demonstrate the use of this strip sensor. The limit of the detection for the fluorescent strip was determined as 102 CFU mL-1, which is 100 times lower than those displayed by enzyme-linked immunosorbent assays, while the time needed for the detection was only 15 min. Furthermore, no cross-reaction with other eight pathogens was found, indicating the good specificity of the strip. This developed LFIA would offer the potential as a useful tool for the quantification of pathogens analysis in the future.

  20. A Harmonic Algorithm for the 3D Strip Packing Problem

    NARCIS (Netherlands)

    N. Bansal (Nikhil); X. Han; K. Iwama; M. Sviridenko; G. Zhang (Guochuan)

    2013-01-01

    htmlabstractIn the three-dimensional (3D) strip packing problem, we are given a set of 3D rectangular items and a 3D box $B$. The goal is to pack all the items in $B$ such that the height of the packing is minimized. We consider the most basic version of the problem, where the items must be packed

  1. MUST: A silicon strip detector array for radioactive beam experiments

    CERN Document Server

    Blumenfeld, Y; Sauvestre, J E; Maréchal, F; Ottini, S; Alamanos, N; Barbier, A; Beaumel, D; Bonnereau, B; Charlet, D; Clavelin, J F; Courtat, P; Delbourgo-Salvador, P; Douet, R; Engrand, M; Ethvignot, T; Gillibert, A; Khan, E; Lapoux, V; Lagoyannis, A; Lavergne, L; Lebon, S; Lelong, P; Lesage, A; Le Ven, V; Lhenry, I; Martin, J M; Musumarra, A; Pita, S; Petizon, L; Pollacco, E; Pouthas, J; Richard, A; Rougier, D; Santonocito, D; Scarpaci, J A; Sida, J L; Soulet, C; Stutzmann, J S; Suomijärvi, T; Szmigiel, M; Volkov, P; Voltolini, G

    1999-01-01

    A new and innovative array, MUST, based on silicon strip technology and dedicated to the study of reactions induced by radioactive beams on light particles is described. The detector consists of 8 silicon strip - Si(Li) telescopes used to identify recoiling light charged particles through time of flight, energy loss and energy measurements and to determine precisely their scattering angle through X, Y position measurements. Each 60x60 mm sup 2 double sided silicon strip detector with 60 vertical and 60 horizontal strips yields an X-Y position resolution of 1 mm, an energy resolution of 50 keV, a time resolution of around 1 ns and a 500 keV energy threshold for protons. The backing Si(Li) detectors stop protons up to 25 MeV with a resolution of approximately 50 keV. CsI crystals read out by photo-diodes which stop protons up to 70 MeV are added to the telescopes for applications where higher energy particles need to be detected. The dedicated electronics in VXIbus standard allow us to house the 968 logic and a...

  2. Use of moisture induced stress testing to evaluate stripping potential of hot mix asphalt (HMA).

    Science.gov (United States)

    2012-07-01

    Stripping of hot mix asphalt (HMA) in the field is an ongoing issue for many Departments of Transportation : (DOTs). A leading cause of stripping is hydraulic scouring. The Moisture Induced Stress Tester (MIST) is a recently : developed technology th...

  3. Performance of the carbon stripping foils in the Argonne FN tandem

    International Nuclear Information System (INIS)

    Den Hartog, P.K.; Munson, F.; Heath, C.; Thomas, G.

    1980-01-01

    Carbon stripping foils produced by the glow discharge cracking of ethylene were produced and the foils were tested in the Argonne FN tandem accelerator. The results are presented and the characteristics of stripping media are discussed

  4. Computerized Decision Support Improves Medication Review Effectiveness : An Experiment Evaluating the STRIP Assistant's Usability

    NARCIS (Netherlands)

    Meulendijk, Michiel C; Spruit, Marco R; Drenth-van Maanen, A Clara; Numans, Mattijs E; Brinkkemper, Sjaak; Jansen, Paul A F; Knol, Wilma

    BACKGROUND: Polypharmacy poses threats to patients' health. The Systematic Tool to Reduce Inappropriate Prescribing (STRIP) is a drug optimization process for conducting medication reviews in primary care. To effectively and efficiently incorporate this method into daily practice, the STRIP

  5. Computerized decision support improves medication review effectiveness: an experiment evaluating the STRIP Assistant’s usability

    NARCIS (Netherlands)

    Meulendijk, M.; Spruit, M.; Drenth-van Maanen, C.; Numans, M.; Brinkkemper, S.; Jansen, P.; Knol, W

    2015-01-01

    Background Polypharmacy poses threats to patients’ health. The Systematic Tool to Reduce Inappropriate Prescribing (STRIP) is a drug optimization process for conducting medication reviews in primary care. To effectively and efficiently incorporate this method into daily practice, the STRIP

  6. Tools for applying lead tape to flat conductor cabling for chemical stripping

    Science.gov (United States)

    Angele, W.

    1969-01-01

    Two tools facilitate chemical stripping of insulation on flat conductor cabling. A tape pressing tool and a taping fixture apply adhesive lead tape with the proper amount of pressure to protect the remaining insulation from the chemical stripping solution.

  7. Extraction and stripping of neodymium (III) and dysprosium (III) by TRUEX solvent

    International Nuclear Information System (INIS)

    Rout, Alok; Venkatesan, K.A.; Antony, M.P.; Srinivasan, T.G.; Vasudeva Rao, P.R.

    2009-01-01

    McCabe-Thiele diagram for the extraction and stripping of Nd (III) and Dy (III) by TRUEX solvent has been constructed to determine the number of stages required for complete extraction and stripping. (author)

  8. Reduced Ang2 expression in aging endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Hohensinner, P.J., E-mail: philipp.hohensinner@meduniwien.ac.at [Department of Internal Medicine II, Medical University of Vienna, Vienna (Austria); Ebenbauer, B. [Department of Internal Medicine II, Medical University of Vienna, Vienna (Austria); Ludwig Boltzmann Cluster for Cardiovascular Research, Vienna (Austria); Kaun, C.; Maurer, G. [Department of Internal Medicine II, Medical University of Vienna, Vienna (Austria); Huber, K. [Ludwig Boltzmann Cluster for Cardiovascular Research, Vienna (Austria); 3rd Medical Department, Wilhelminenhospital, Vienna (Austria); Sigmund Freud University, Medical Faculty, Vienna (Austria); Wojta, J. [Department of Internal Medicine II, Medical University of Vienna, Vienna (Austria); Ludwig Boltzmann Cluster for Cardiovascular Research, Vienna (Austria); Core Facilities, Medical University of Vienna, Vienna (Austria)

    2016-06-03

    Aging endothelial cells are characterized by increased cell size, reduced telomere length and increased expression of proinflammatory cytokines. In addition, we describe here that aging reduces the migratory distance of endothelial cells. Furthermore, we observe an increase of the quiescence protein Ang1 and a decrease of the endothelial activation protein Ang2 upon aging. Supplementing Ang2 to aged endothelial cells restored their migratory capacity. We conclude that aging shifts the balance of the Ang1/Ang2 network favouring a quiescent state. Activation of endothelial cells in aging might be necessary to enhance wound healing capacities. -- Highlights: •Endothelial cells display signs of aging before reaching proliferative senescence. •Aging endothelial cells express more angiopoietin 1 and less angiopoietin 2 than young endothelial cells. •Migratory capacity is reduced in aging endothelial cells.

  9. Reduced Ang2 expression in aging endothelial cells

    International Nuclear Information System (INIS)

    Hohensinner, P.J.; Ebenbauer, B.; Kaun, C.; Maurer, G.; Huber, K.; Wojta, J.

    2016-01-01

    Aging endothelial cells are characterized by increased cell size, reduced telomere length and increased expression of proinflammatory cytokines. In addition, we describe here that aging reduces the migratory distance of endothelial cells. Furthermore, we observe an increase of the quiescence protein Ang1 and a decrease of the endothelial activation protein Ang2 upon aging. Supplementing Ang2 to aged endothelial cells restored their migratory capacity. We conclude that aging shifts the balance of the Ang1/Ang2 network favouring a quiescent state. Activation of endothelial cells in aging might be necessary to enhance wound healing capacities. -- Highlights: •Endothelial cells display signs of aging before reaching proliferative senescence. •Aging endothelial cells express more angiopoietin 1 and less angiopoietin 2 than young endothelial cells. •Migratory capacity is reduced in aging endothelial cells.

  10. Pros and cons of flowers strips for farmers. A review

    Directory of Open Access Journals (Sweden)

    Uyttenbroeck, R.

    2016-01-01

    Full Text Available Description of the subject. To counteract environmental problems due to agricultural intensification, European farmers can apply agri-environmental schemes in their fields. Flower strips are one example of these schemes, with the aim of supporting biodiversity, leading to an increase in "useful" species groups such as pollinators for crop pollination and natural enemies for pest control. However, to our knowledge, a complete appraisal of the pros and cons of flower strips, from a farmer's point of view, does not yet exist. It is proposed that better and more complete information could increase the adoption and implementation of such agri-environmental schemes. Objectives. This study aims 1 to assess the pros and cons of flower strips, from a farmer's point of view, and 2 to highlight the knowledge gaps that exist in the scientific literature, for the different types of pros and cons. Method. We listed the different components of the appraisal of pros and cons and conducted a systematic screening of the scientific literature on flower strips and these components. Results. The largest part of the 31 selected studies was concerning agronomical and ecological processes, such as pollination and animal pest control. Most of them indicated positive effects of flower strips. For many components of the appraisal, mostly economic and social ones, few or no studies were found. Conclusions. While a positive balance of pros and cons, from a farmer's point of view, came from our literature screening, large research gaps still remain and more research is required, especially in the economic and social components of the evaluation.

  11. The Examination of Fatty Acid Taste with Edible Strips

    Science.gov (United States)

    Ebba, Sahbina; Abarintos, Ray A.; Kim, Dae G.; Tiyouh, Melissa; Stull, Judith C.; Movalia, Ankur; Smutzer, Gregory

    2012-01-01

    The objective of this study was to determine whether humans could detect long-chain fatty acids when these lipid molecules are delivered to the oral cavity by edible taste strips. For suprathreshold studies, up to 1.7 umoles of stearic acid or linoleic acid were incorporated into 0.03 mm thick, one-inch square taste strips. Normalized taste intensity values for stearic acid were in the barely detectable range, with values equal to, or slightly above control strips. One-third of test subjects described the taste quality as oily/fatty/waxy. Approximately 75% of test subjects could detect the presence of linoleic acid when this fatty acid was incorporated into dissolvable strips. Normalized taste intensity values for linoleic acid were in the weak to moderate range. The most commonly reported taste quality responses for linoleic acid were fatty/oily/waxy, or bitter. When nasal airflow was obstructed, the perceived taste intensity of linoleic acid decreased by approximately 40 percent. Taste intensity values and taste quality responses for linoleic acid were then compared among tasters and non-tasters of 6-n-propylthiouracil (PROP). Individuals who could detect the bitter taste of PROP reported higher taste intensity values for linoleic acid compared with PROP non-tasters. However, taste quality responses for linoleic acid were similar among both PROP tasters and PROP non-tasters. These results indicate that humans can detect long-chain fatty acids by both olfactory and non-olfactory pathways when these hydrophobic molecules are delivered to the oral cavity by means of edible taste strips. These studies further show that genetic variation in taste sensitivity to PROP affects chemosensory responses to the cis-unsaturated fatty acid linoleic acid in the oral cavity. PMID:22521910

  12. 6-Hydroxydopamine induces brain vascular endothelial inflammation.

    Science.gov (United States)

    Fu, Qizhi; Song, Runluo; Yang, Zhongxi; Shan, Qi; Chen, Wenna

    2017-11-01

    Disruption of the blood-brain barrier associated with endothelial dysfunction is an important hallmark of Parkinson's disease (PD). 6-Hydroxydopamine (6-OHDA) is a synthetic dopamine derivate often used to model PD as it results in retrograde degeneration of striatal dopaminergic (DA) terminals. Presently, the effects of 6-OHDA on endothelial dysfunction remain unknown. Using a 6-OHDA rodent model of PD, we found that administration of 6-OHDA could increase the expression of endothelial adhesion molecules, such as intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and E-selectin. An in vitro study displayed that treatment with 6-OHDA increased the release of these molecules in human brain microvascular endothelial cells in a dose-dependent manner. Correspondingly, 6-OHDA significantly increased attachment of THP-1 monocytes to brain endothelial cells. In addition, real-time polymerase chain reaction and enzyme-linked immunosorbent assay results indicated that 6-OHDA elevated the production of proinflammatory cytokines, such as interleukin-1β, interleukin-6, and tumor necrosis factor-α. Furthermore, 6-OHDA treatment increased the expression of cyclooxygenase-2 and inducible nitric oxide synthase, as well as the production of prostaglandin E2 and nitric oxide. Importantly, 6-OHDA elevated the transcriptional activity of NF-кB by increasing the phosphorylation, degradation, and subsequent nuclear translocation of p65. Mechanistically, the angiotensin II type 1 receptor was found to mediate 6-OHDA-induced endothelial dysfunction. Our findings suggest that 6-OHDA-induced endothelial inflammation may play an important role in the pathogenesis of PD. © 2017 IUBMB Life, 69(11):887-895, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

  13. Comparison of blood glucose test strips in the detection of neonatal hypoglycaemia

    OpenAIRE

    Wilkins, B H; Kalra, D

    1982-01-01

    Blood glucose levels were estimated in 101 neonatal blood samples using three glucose test strip methods and the results compared with those from a laboratory. BM-test-glycemie 20-800 test strips and Reflotest-hypoglycemie test strips gave a rapid and reliable estimate of blood glucose level in the range 0-8 mmol/l (0-140 mg/100 ml). Dextrostix test strips tended to overestimate all blood glucose levels.

  14. Sediment removal by prairie filter strips in row-cropped ephemeral watersheds

    Science.gov (United States)

    Matthew J. Helmers; Xiaobo Zhou; Heidi Asbjornsen; Randy Kolka; Mark D. Tomer; Richard M. Cruse

    2012-01-01

    Twelve small watersheds in central Iowa were used to evaluate the eff ectiveness of prairie filter strips (PFS) in trapping sediment from agricultural runoff. Four treatments with PFS of different size and location (100% rowcrop, 10% PFS of total watershed area at footslope, 10% PFS at footslope and in contour strips, 20% PFS at footslope and in contour strips)...

  15. 77 FR 73010 - Polyethylene Terephthalate Film, Sheet, and Strip From the United Arab Emirates; Preliminary...

    Science.gov (United States)

    2012-12-07

    ... International Trade Administration Polyethylene Terephthalate Film, Sheet, and Strip From the United Arab... terephthalate film, sheet, and strip (PET Film) from the United Arab Emirates (UAE). The period of review (POR... Terephthalate Film, Sheet, and Strip from the United Arab Emirates'' (Preliminary Decision Memorandum), dated...

  16. 78 FR 77649 - Polyethylene Terephthalate Film, Sheet, and Strip From the United Arab Emirates; Preliminary...

    Science.gov (United States)

    2013-12-24

    ... International Trade Administration Polyethylene Terephthalate Film, Sheet, and Strip From the United Arab... antidumping duty order on polyethylene terephthalate film, sheet, and strip (PET Film) from the United Arab... Strip from the United Arab Emirates'' (Preliminary Decision Memorandum), dated concurrently with this...

  17. 76 FR 11509 - Brass Sheet and Strip From France, Germany, Italy, and Japan

    Science.gov (United States)

    2011-03-02

    ... COMMISSION Brass Sheet and Strip From France, Germany, Italy, and Japan AGENCY: United States International... brass sheet and strip from France, Germany, Italy, and Japan. SUMMARY: The Commission hereby gives... strip from France, Germany, Italy, and Japan would be likely to lead to continuation or recurrence of...

  18. 77 FR 23508 - Brass Sheet and Strip From France, Germany, Italy, and Japan

    Science.gov (United States)

    2012-04-19

    ... COMMISSION Brass Sheet and Strip From France, Germany, Italy, and Japan Determination On the basis of the... revocation of the antidumping duty orders on brass sheet and strip from France, Germany, Italy, and Japan...), entitled Brass Sheet and Strip from France, Germany, Italy, and Japan: Investigation Nos. 731-TA-313, 314...

  19. A design aid for sizing filter strips using buffer area ratio

    Science.gov (United States)

    M.G. Dosskey; M.J. Helmers; D.E. Eisenhauer

    2011-01-01

    Nonuniform field runoff can reduce the effectiveness of filter strips that are a uniform size along a field margin. Effectiveness can be improved by placing more filter strip where the runoff load is greater and less where the load is smaller. A modeling analysis was conducted of the relationship between pollutant trapping efficiency and the ratio of filter strip area...

  20. Effect of Strip Mining on Water Quality in Small Streams in Eastern Kentucky, 1967-1975

    Science.gov (United States)

    Kenneth L. Dyer; Willie R. Curtis

    1977-01-01

    Eight years of streamflow data are analyzed to show the effects of strip mining on chemical quality of water in six first-order streams in Breathitt County, Kentucky. All these watersheds were unmined in August, 1967, but five have since been strip mined. The accumulated data from this case history study indicate that strip mining causes large increases in the...

  1. Flexible Faraday Cage with a Twist: Surface Charge on a Mobius Strip

    Science.gov (United States)

    Stewart, Sean

    2007-01-01

    Once an intriguing topological novelty known only to mathematicians, the Mobius strip has become a source of fascination and inspiration to the layperson and artist alike. Principal among its features are the two strange properties that the Mobius strip is a surface with only one side and one edge. A Mobius strip is readily formed by taking a long…

  2. Dietary phosphorus acutely impairs endothelial function.

    Science.gov (United States)

    Shuto, Emi; Taketani, Yutaka; Tanaka, Rieko; Harada, Nagakatsu; Isshiki, Masashi; Sato, Minako; Nashiki, Kunitaka; Amo, Kikuko; Yamamoto, Hironori; Higashi, Yukihito; Nakaya, Yutaka; Takeda, Eiji

    2009-07-01

    Excessive dietary phosphorus may increase cardiovascular risk in healthy individuals as well as in patients with chronic kidney disease, but the mechanisms underlying this risk are not completely understood. To determine whether postprandial hyperphosphatemia may promote endothelial dysfunction, we investigated the acute effect of phosphorus loading on endothelial function in vitro and in vivo. Exposing bovine aortic endothelial cells to a phosphorus load increased production of reactive oxygen species, which depended on phosphorus influx via sodium-dependent phosphate transporters, and decreased nitric oxide production via inhibitory phosphorylation of endothelial nitric oxide synthase. Phosphorus loading inhibited endothelium-dependent vasodilation of rat aortic rings. In 11 healthy men, we alternately served meals containing 400 mg or 1200 mg of phosphorus in a double-blind crossover study and measured flow-mediated dilation of the brachial artery before and 2 h after the meals. The high dietary phosphorus load increased serum phosphorus at 2 h and significantly decreased flow-mediated dilation. Flow-mediated dilation correlated inversely with serum phosphorus. Taken together, these findings suggest that endothelial dysfunction mediated by acute postprandial hyperphosphatemia may contribute to the relationship between serum phosphorus level and the risk for cardiovascular morbidity and mortality.

  3. ENDOTHELIAL DYSFUNCTION IN ISCHEMIC HEART DISEASE

    Directory of Open Access Journals (Sweden)

    N. E. Zakirova

    2008-01-01

    Full Text Available Aim. To assess the role of endothelial vasodilating, vasoconstrictive and adhesive dysfunction in the development of angina pectoris (AP in patients with ischemic heart disease (IHD.Material and methods. 83 patients with IHD were included in the study. 30 patients had AP of functional class (FC-II, 27 patients - FC-III and 26 patients - FC-IV. The control group consisted of 25 healthy persons. Bicycle ergometry, daily ECG monitoring and echocardiography were used for verification of IHD. Endothelial vasodilating function was assessed by endothelium-dependent (EDVD and endothelium-independent vasodilatation (EIDVD of brachial artery. Vasoconstrictive function was assessed by the level of endothelin (ET-1. Endothelial adhesive function was evaluated by plasma concentration of intracellular adhesion molecules – JCAM-1, VCAM-1 and Е-selectin.Results. Normal EDVD and EIDVD were observed in patients with AP of FC-II. The more severe FC of AP the more prominent endothelial vasodilating dysfunction was revealed as well as the higher levels of ET-1 and intracellular adhesion molecules. Patients with AP of FC-IV had hyperexpression of JCAM-1, VCAM-1, Е-selectin and ET-1 and low levels of EDVD and EIDVD.Conclusion. Progression of IHD related with growing endothelial vasodilating, vasoconstrictive and adhesive dysfunction.

  4. [Assessment of endothelial function in autoimmune diseases].

    Science.gov (United States)

    Benhamou, Y; Bellien, J; Armengol, G; Gomez, E; Richard, V; Lévesque, H; Joannidès, R

    2014-08-01

    Numerous autoimmune-inflammatory rheumatic diseases have been associated with accelerated atherosclerosis or other types of vasculopathy leading to an increase in cardiovascular disease incidence. In addition to traditional cardiovascular risk factors, endothelial dysfunction is an important early event in the pathogenesis of atherosclerosis, contributing to plaque initiation and progression. Endothelial dysfunction is characterized by a shift of the actions of the endothelium toward reduced vasodilation, a proinflammatory and a proadhesive state, and prothrombic properties. Therefore, assessment of endothelial dysfunction targets this vascular phenotype using several biological markers as indicators of endothelial dysfunction. Measurements of soluble adhesion molecules (ICAM-1, VCAM-1, E-selectin), pro-thrombotic factors (thrombomodulin, von Willebrand factor, plasminogen activator inhibitor-1) and inflammatory cytokines are most often performed. Regarding the functional assessment of the endothelium, the flow-mediated dilatation of conduit arteries is a non-invasive method widely used in pathophysiological and interventional studies. In this review, we will briefly review the most relevant information upon endothelial dysfunction mechanisms and explorations. We will summarize the similarities and differences in the biological and functional assessments of the endothelium in different autoimmune diseases. Copyright © 2013 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  5. Endothelial Extracellular Vesicles-Promises and Challenges.

    Science.gov (United States)

    Hromada, Carina; Mühleder, Severin; Grillari, Johannes; Redl, Heinz; Holnthoner, Wolfgang

    2017-01-01

    Extracellular vesicles, including exosomes, microparticles, and apoptotic bodies, are phospholipid bilayer-enclosed vesicles that have once been considered as cell debris lacking biological functions. However, they have recently gained immense interest in the scientific community due to their role in intercellular communication, immunity, tissue regeneration as well as in the onset, and progression of various pathologic conditions. Extracellular vesicles of endothelial origin have been found to play a versatile role in the human body, since they are on the one hand known to contribute to cardiovascular diseases, but on the other hand have also been reported to promote endothelial cell survival. Hence, endothelial extracellular vesicles hold promising therapeutic potential to be used as a new tool to detect as well as treat a great number of diseases. This calls for clinically approved, standardized, and efficient isolation and characterization protocols to harvest and purify endothelial extracellular vesicles. However, such methods and techniques to fulfill stringent requirements for clinical trials have yet to be developed or are not harmonized internationally. In this review, recent advances and challenges in the field of endothelial extracellular vesicle research are discussed and current problems and limitations regarding isolation and characterization are pointed out.

  6. Endothelial Cell Response to Fusobacterium nucleatum.

    Science.gov (United States)

    Mendes, Reila Tainá; Nguyen, Daniel; Stephens, Danielle; Pamuk, Ferda; Fernandes, Daniel; Van Dyke, Thomas E; Kantarci, Alpdogan

    2016-07-01

    Vascular response is an essential aspect of an effective immune response to periodontal disease pathogens, as new blood vessel formation contributes to wound healing and inflammation. Gaining a greater understanding of the factors that affect vascular response may then contribute to future breakthroughs in dental medicine. In this study, we have characterized the endothelial cell response to the common bacterium Fusobacterium nucleatum, an important bridging species that facilitates the activity of late colonizers of the dental biofilm. Endothelial cells were infected with Fusobacterium nucleatum (strain 25586) for periods of 4, 12, 24, or 48 h. Cell proliferation and tube formation were analyzed, and expression of adhesion molecules (CD31 and CD34) and vascular endothelial growth factor (VEGF) receptors 1 and 2 was measured by fluorescence-activated cell sorter (FACS) analysis. Data indicate that F. nucleatum impaired endothelial cell proliferation and tube formation. The findings suggest that the modified endothelial cell response acts as a mechanism promoting the pathogenic progression of periodontal diseases and may potentially suggest the involvement of periodontopathogens in systemic diseases associated with periodontal inflammation. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  7. Removal of nitrogen from swine manure by ammonia stripping; Reduccion del contenido en nitrogeno amoniacal del purin procino mediante la tecnica de stripping

    Energy Technology Data Exchange (ETDEWEB)

    Hidalgo, M. D.; Alamo, J. del; Nunez, U.; Irusta, R. [Grupo de Tecnologia Ambiental . Laboratorio de Analisis y Estudios Medioambientales. Valladolid (Spain)

    2001-07-01

    Lab scale experiments were undertaken to investigate air stripping as method for removing ammonia from cattle effluents and, more concretely, from the liquid fraction of swine manure. The effects of packet size, influent pH, air to liquid flow ratio and liquid recirculation flow in the stripping tower were investigated. The high ammonia removal efficiency of the air stripping method indicates that it could provide an interim solution for current waste management problems in the swine industry. (Author) 5 refs.

  8. The new silicon strip detectors for the CMS tracker upgrade

    International Nuclear Information System (INIS)

    Dragicevic, M.

    2010-01-01

    The first introductory part of the thesis describes the concept of the CMS experiment. The tasks of the various detector systems and their technical implementations in CMS are explained. To facilitate the understanding of the basic principles of silicon strip sensors, the subsequent chapter discusses the fundamentals in semiconductor technology, with particular emphasis on silicon. The necessary process steps to manufacture strip sensors in a so-called planar process are described in detail. Furthermore, the effects of irradiation on silicon strip sensors are discussed. To conclude the introductory part of the thesis, the design of the silicon strip sensors of the CMS Tracker are described in detail. The choice of the substrate material and the complex geometry of the sensors are reviewed and the quality assurance procedures for the production of the sensors are presented. Furthermore the design of the detector modules are described. The main part of this thesis starts with a discussion on the demands on the tracker caused by the increase in luminosity which is proposed as an upgrade to the LHC accelerator (sLHC). This chapter motivates the work I have conducted and clarifies why the solutions proposed by myself are important contributions to the upgrade of the CMS tracker. The following chapters present the concepts that are necessary to operate the silicon strip sensors at sLHC luminosities and additional improvements to the construction and quality assurance of the sensors and the detector modules. The most important concepts and works presented in chapters 7 to 9 are: Development of a software framework to enable the flexible and quick design of test structures and sensors. Selecting a suitable sensor material which is sufficiently radiation hard. Design, implementation and production of a standard set of test structures to enable the quality assurance of such sensors and any future developments. Electrical characterisation of the test structures and analysis

  9. Effects of helium on inflammatory and oxidative stress-induced endothelial cell damage

    NARCIS (Netherlands)

    Smit, Kirsten F.; Kerindongo, Raphaela P.; Böing, Anita; Nieuwland, Rienk; Hollmann, Markus W.; Preckel, Benedikt; Weber, Nina C.

    2015-01-01

    Helium induces preconditioning in human endothelium protecting against postischemic endothelial dysfunction. Circulating endothelial microparticles are markers of endothelial dysfunction derived in response to injury. Another noble gas, xenon, protected human umbilical vein endothelial cells (HUVEC)

  10. Isolation and culture of pulmonary endothelial cells.

    Science.gov (United States)

    Ryan, U S

    1984-06-01

    Methods for isolation, identification and culture of pulmonary endothelial cells are now routine. In the past, methods of isolation have used proteolytic enzymes to detach cells; thereafter, traditional methods for cell passaging have used trypsin/EDTA mixtures. Cells isolated and passaged using proteolytic enzymes have been useful in establishing the field and in verifying certain endothelial properties. However, there is a growing awareness of the role of endothelial cells in processing vasoactive substances, in responding to hormones and other agonists and in cell-cell interactions with other cell types of the vascular wall, with blood cells and with cellular products. Consequently, a new requirement has arisen for cells in vitro that maintain the differentiated properties of their counterparts in vivo. The deleterious effects of trypsin and other proteolytic enzymes commonly used in cell culture on surface structures of endothelial cells such as enzymes, receptors and junctional proteins, as well as on extracellular layers such as the glycocalyx or "endothelial fuzz," have led to the development of methods that avoid use of proteolytic enzymes at both the isolation step and during subsequent subculture. This chapter describes traditional methods for isolating pulmonary endothelial cells but emphasizes newer approaches using mechanical harvest and scale-up using microcarriers. The new methods allow maintenance of long-term, large-scale cultures of cells that retain the full complement of surface properties and that maintain the cobblestone monolayer morphology and differentiated functional properties. Methods for identification of isolated cells are therefore also considered as methods for validation of cultures during their in vitro lifespan.

  11. Endothelial cells, endoplasmic reticulum stress and oxysterols

    Directory of Open Access Journals (Sweden)

    F. Luchetti

    2017-10-01

    Full Text Available Oxysterols are bioactive lipids that act as regulators of lipid metabolism, inflammation, cell viability and are involved in several diseases, including atherosclerosis. Mounting evidence linked the atherosclerosis to endothelium dysfunction; in fact, the endothelium regulates the vascular system with roles in processes such as hemostasis, cell cholesterol, hormone trafficking, signal transduction and inflammation. Several papers shed light the ability of oxysterols to induce apoptosis in different cell lines including endothelial cells. Apoptotic endothelial cell and endothelial denudation may constitute a critical step in the transition to plaque erosion and vessel thrombosis, so preventing the endothelial damaged has garnered considerable attention as a novel means of treating atherosclerosis. Endoplasmic reticulum (ER is the site where the proteins are synthetized and folded and is necessary for most cellular activity; perturbations of ER homeostasis leads to a condition known as endoplasmic reticulum stress. This condition evokes the unfolded protein response (UPR an adaptive pathway that aims to restore ER homeostasis. Mounting evidence suggests that chronic activation of UPR leads to cell dysfunction and death and recently has been implicated in pathogenesis of endothelial dysfunction. Autophagy is an essential catabolic mechanism that delivers misfolded proteins and damaged organelles to the lysosome for degradation, maintaining basal levels of autophagic activity it is critical for cell survival. Several evidence suggests that persistent ER stress often results in stimulation of autophagic activities, likely as a compensatory mechanism to relieve ER stress and consequently cell death. In this review, we summarize evidence for the effect of oxysterols on endothelial cells, especially focusing on oxysterols-mediated induction of endoplasmic reticulum stress.

  12. Identification of epigenetically silenced genes in tumor endothelial cells

    NARCIS (Netherlands)

    Hellebrekers, Debby M. E. I.; Melotte, Veerle; Vire, Emmanuelle; Langenkamp, Elise; Molema, Grietje; Fuks, Francois; Herman, James G.; Van Criekinge, Wim; Griffioen, Arjan W.; van Engeland, Manon

    2007-01-01

    Tumor angiogenesis requires intricate regulation of gene expression in endothelial cells. We recently showed that DNA methyltransferase (DNMT) and histone deacetylase (HDAC) inhibitors directly repress endothelial cell growth and tumor angiogenesis, suggesting that epigenetic modifications mediated

  13. Qidantongmai Protects Endothelial Cells Against Hypoxia-Induced ...

    African Journals Online (AJOL)

    induced damage. The ability of QDTM to modulate the serum VEGF-A level may play an important role in its effects on endothelial cells. Key words: Traditional Chinese Medicine, human umbilical vein endothelial cells, hypoxia, VEGF ...

  14. Corneal endothelial dysfunction in Pearson syndrome.

    Science.gov (United States)

    Kasbekar, Shivani A; Gonzalez-Martin, Jose A; Shafiq, Ayad E; Chandna, Arvind; Willoughby, Colin E

    2013-01-01

    Mitochondrial disorders are associated with well recognized ocular manifestations. Pearson syndrome is an often fatal, multisystem, mitochondrial disorder that causes variable bone marrow, hepatic, renal and pancreatic exocrine dysfunction. Phenotypic progression of ocular disease in a 12-year-old male with Pearson syndrome is described. This case illustrates phenotypic drift from Pearson syndrome to Kearns-Sayre syndrome given the patient's longevity. Persistent corneal endothelial failure was noted in addition to ptosis, chronic external ophthalmoplegia and mid-peripheral pigmentary retinopathy. We propose that corneal edema resulting from corneal endothelial metabolic pump failure occurs within a spectrum of mitochondrial disorders.

  15. Dietary behaviours and dental fluorosis among Gaza Strip children.

    Science.gov (United States)

    Abuhaloob, L; Abed, Y

    2013-07-01

    A high prevalence of dental fluorosis has been identified among children in the Gaza Strip. This study aimed to determine the history of breastfeeding and dietary behaviours among children in the Gaza Strip and to examine potential associations with the prevalence and severity of dental fluorosis. A cross-sectional study recruited a stratified cluster random sample of 350 children aged 12-18 years and their mothers. Data about dietary behaviours in the first 7 years of life were collected by interview questionnaire. Dental fluorosis was determined using the Thyllstrup-Fejerskov index. A majority of children were breastfed exclusively in the first 6 months (82.9%) but 98.1% were given tea in the first year of life. The prevalence of dental fluorosis was 78.0%. Both intake of animal proteins and plant proteins were negatively associated with the prevalence and severity of dental fluorosis. Further studies to investigate fluoride intake is required to plan preventive interventions.

  16. Slip Morphology of Elastic Strips on Frictional Rigid Substrates.

    Science.gov (United States)

    Sano, Tomohiko G; Yamaguchi, Tetsuo; Wada, Hirofumi

    2017-04-28

    The morphology of an elastic strip subject to vertical compressive stress on a frictional rigid substrate is investigated by a combination of theory and experiment. We find a rich variety of morphologies, which-when the bending elasticity dominates over the effect of gravity-are classified into three distinct types of states: pinned, partially slipped, and completely slipped, depending on the magnitude of the vertical strain and the coefficient of static friction. We develop a theory of elastica under mixed clamped-hinged boundary conditions combined with the Coulomb-Amontons friction law and find excellent quantitative agreement with simulations and controlled physical experiments. We also discuss the effect of gravity in order to bridge the difference in the qualitative behaviors of stiff strips and flexible strings or ropes. Our study thus complements recent work on elastic rope coiling and takes a significant step towards establishing a unified understanding of how a thin elastic object interacts vertically with a solid surface.

  17. Feature curve extraction from point clouds via developable strip intersection

    Directory of Open Access Journals (Sweden)

    Kai Wah Lee

    2016-04-01

    Full Text Available In this paper, we study the problem of computing smooth feature curves from CAD type point clouds models. The proposed method reconstructs feature curves from the intersections of developable strip pairs which approximate the regions along both sides of the features. The generation of developable surfaces is based on a linear approximation of the given point cloud through a variational shape approximation approach. A line segment sequencing algorithm is proposed for collecting feature line segments into different feature sequences as well as sequential groups of data points. A developable surface approximation procedure is employed to refine incident approximation planes of data points into developable strips. Some experimental results are included to demonstrate the performance of the proposed method.

  18. Cooling characteristics of a strip fin heat sink

    International Nuclear Information System (INIS)

    Riu, Kap Jong; Park, Cheol Woo; Jang, Chung Sun; Kim, Hyun Woo

    2005-01-01

    Air-cooled heat sinks are employed in many electronic cooling applications since they provide significant heat transfer enhancement and operational flexibility. Strip-shaped fin heat sink is of interest and needs to be investigated as general cooling products for more applicability. The purposes of this study are to evaluate heat sink performance without bypass flow condition and to determine optimal heat sink geometries. The results show that the decreasing rate of thermal resistance of a heat sink decreases with increasing inlet air velocity, and the increasing rate of pressure drop increases with increasing inlet air velocity, but is not affected by input power. The increasing rate of optimal longitudinal fin spacing is larger than that of transverse fin spacing. The strip fin heat sink tested in this study showed better cooling performance compared to that of other plate fin type

  19. The Data Quality Monitoring for the CMS Silicon Strip Tracker

    CERN Document Server

    Adler, V; Bainbridge, R; Benucci, L; Borgia, M A; Borrello, L; Cole, J; Cripps, N; Delmeire, E; Dero, V; Dutta, S; Giordano, D; Hammad, G H; Hashemi, H; Le Bihan, A C; Le Bourgeois, M; Palmonari, F; Pierro, A; Zito, G

    2009-01-01

    The CMS Silicon Strip Tracker (SST), consisting of more than 10 million channels, is organized in about 15,000 detector modules and it is the largest silicon strip tracker ever built for high energy physics experiments. The Data Quality Monitoring system for the Tracker has been developed within the CMS Software framework. More than 100,000 monitorable quantities need to be managed by the DQM system that organizes them in a hierarchical structure reflecting the detector arrangement in subcomponents and the various levels of data processing. Monitorable quantities computed at the level of individual detectors are processed to extract automatic quality checks and summary results that can be visualized with specialized graphical user interfaces. In view of the great complexity of the CMS Tracker detector the standard visualization tools based on histograms have been complemented with 2 and 3 dimensional graphical images of the subdetector that can show the whole detector down to single channel resolution. The fu...

  20. Silicon strip detectors for the ATLAS HL-LHC upgrade

    CERN Document Server

    Gonzalez Sevilla, S; The ATLAS collaboration

    2011-01-01

    The LHC upgrade is foreseen to increase the ATLAS design luminosity by a factor ten, implying the need to build a new tracker suited to the harsh HL-LHC conditions in terms of particle rates and radiation doses. In order to cope with the increase in pile-up backgrounds at the higher luminosity, an all silicon detector is being designed. To successfully face the increased radiation dose, a new generation of extremely radiation hard silicon detectors is being designed. We give an overview of the ATLAS tracker upgrade project, in particular focusing on the crucial innermost silicon strip layers. Results from a wide range of irradiated silicon detectors for the strip region of the future ATLAS tracker are presented. Layout concepts for lightweight yet mechanically very rigid detector modules with high service integration are shown.