Comparison of clinical outcomes of multi-point umbrella suturing and single purse suturing with two-point traction after procedure for prolapse and hemorrhoids (PPH) surgery.

Science.gov (United States)

Jiang, Huiyong; Hao, Xiuyan; Xin, Ying; Pan, Youzhen

2017-11-01

To compare the clinical outcomes of multipoint umbrella suture and single-purse suture with two-point traction after procedure for prolapse and hemorrhoids surgery (PPH) for the treatment of mixed hemorrhoids. Ninety patients were randomly divided into a PPH plus single-purse suture group (Group A) and a PPH plus multipoint umbrella suture (Group B). All operations were performed by an experienced surgeon. Operation time, width of the specimen, hemorrhoids retraction extent, postoperative pain, postoperative bleeding, and length of hospitalization were recorded and compared. Statistical analysis was conducted by t-test and χ2 test. There were no significant differences in sex, age, course of disease, and degree of prolapse of hemorrhoids between the two groups. The operative time in Group A was significantly shorter than that in Group B (P hemorrhoid core retraction were significantly lower in Group B (P  0.05 for all comparisons) was observed. The multipoint umbrella suture showed better clinical outcomes because of its targeted suture according to the extent of hemorrhoid prolapse. Copyright © 2017. Published by Elsevier Ltd.

Outcomes of the modified Brostrom procedure using suture anchors for chronic lateral ankle instability--a prospective, randomized comparison between single and double suture anchors.

Science.gov (United States)

Cho, Byung-Ki; Kim, Yong-Min; Kim, Dong-Soo; Choi, Eui-Sung; Shon, Hyun-Chul; Park, Kyoung-Jin

2013-01-01

The present prospective, randomized study was conducted to compare the clinical outcomes of the modified Brostrom procedure using single and double suture anchors for chronic lateral ankle instability. A total of 50 patients were followed up for more than 2 years after undergoing the modified Brostrom procedure. Of the 50 procedures, 25 each were performed using single and double suture anchors by 1 surgeon. The Karlsson scale had improved significantly to 89.8 points and 90.6 points in the single and double anchor groups, respectively. Using the Sefton grading system, 23 cases (92%) in the single anchor group and 22 (88%) in the double anchor group achieved satisfactory results. The talar tilt angle and anterior talar translation on stress radiographs using the Telos device had improved significantly to an average of 5.7° and 4.6 mm in the single anchor group and 4.5° and 4.3 mm in the double anchor group, respectively. The double anchor technique was superior with respect to the postoperative talar tilt. The single and double suture anchor techniques produced similar clinical and functional outcomes, with the exception of talar tilt as a reference of mechanical stability. The modified Brostrom procedure using both single and double suture anchors appears to be an effective treatment method for chronic lateral ankle instability. Copyright © 2013 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

A comparison of single-suture and double-suture incision closures in seaward-migrating juvenile Chinook salmon implanted with acoustic transmitters: implications for research in river basins containing hydropower structures

Energy Technology Data Exchange (ETDEWEB)

Brown, Richard S.; Deters, Katherine A.; Cook, Katrina V.; Eppard, M. B.

2013-07-15

Reductions in the size of acoustic transmitters implanted in migrating juvenile salmonids have resulted in the ability to make shorter incisions that may warrant using only a single suture for closure. However, it is not known if one suture will sufficiently hold the incision closed, particularly when outward pressure is placed on the surgical site such as when migrating fish experience pressure changes associated with passage at hydroelectric dams. The objective of this research was to evaluate the effectiveness of single-suture incision closures on juvenile Chinook salmon (Oncorhynchus tshawytscha). Juvenile Chinook salmon were surgically implanted with a 2012 Juvenile Salmon Acoustic Telemetry System (JSATS) transmitter (0.30 g) and a passive integrated transponder tag (0.10 g) and incisions were closed with either one suture or two sutures. Mortality and tag retention were monitored and fish were examined after 7 and 14 days to evaluate tissue responses. In a separate experiment, surgically implanted fish were exposed to simulated turbine passage and then examined for expulsion of transmitters, expulsion of viscera through the incision, and mortal injury. With incisions closed using a single suture, there was no mortality or tag loss and similar or reduced tissue reaction compared to incisions closed with two sutures. Further, surgery time was significantly reduced when one suture was used, which leads to less handling and reduced stress. No tags were expelled during pressure scenarios and expulsion of viscera only occurred in two non-mortally injured fish (5%) with single sutures that were also exposed to very high pressure changes. No viscera expulsion was present in fish exposed to pressure scenarios likely representative of hydroturbine passage at many Columbia River dams (e.g. <2.7 ratio of pressure change; an acclimation pressure of 146.2 absolute kpa and a lowest exposure pressure of ~ 53.3 absolute kpa). Based on these results, we recommend the use of a

Load response and gap formation in a single-row cruciate suture rotator cuff repair.

Science.gov (United States)

Huntington, Lachlan; Richardson, Martin; Sobol, Tony; Caldow, Jonathon; Ackland, David C

2017-06-01

Double-row rotator cuff tendon repair techniques may provide superior contact area and strength compared with single-row repairs, but are associated with higher material expenses and prolonged operating time. The purpose of this study was to evaluate gap formation, ultimate tensile strength and stiffness of a single-row cruciate suture rotator cuff repair construct, and to compare these results with those of the Mason-Allen and SutureBridge repair constructs. Infraspinatus tendons from 24 spring lamb shoulders were harvested and allocated to cruciate suture, Mason-Allen and SutureBridge repair groups. Specimens were loaded cyclically between 10 and 62 N for 200 cycles, and gap formation simultaneously measured using a high-speed digital camera. Specimens were then loaded in uniaxial tension to failure, and construct stiffness and repair strength were evaluated. Gap formation in the cruciate suture repair was significantly lower than that of the Mason-Allen repair (mean difference = 0.6 mm, P = 0.009) and no different from that of the SutureBridge repair (P > 0.05). Both the cruciate suture repair (mean difference = 15.7 N/mm, P = 0.002) and SutureBridge repair (mean difference = 15.8 N/mm, P = 0.034) were significantly stiffer than that of the Mason-Allen repair; however, no significant differences in ultimate tensile strength between repair groups were discerned (P > 0.05). The cruciate suture repair construct, which may represent a simple and cost-effective alternative to double-row and double-row equivalent rotator cuff repairs, has comparable biomechanical strength and integrity with that of the SutureBridge repair, and may result in improved construct longevity and tendon healing compared with the Mason-Allen repair. © 2017 Royal Australasian College of Surgeons.

Comparative evaluation of entero-anastomosis by inversion techniques with different suturing materials in bovine [Water buffalo

Energy Technology Data Exchange (ETDEWEB)

Gupta, S. C.P.; Khan, A. A.; Dass, L. L.; Sahay, P. N.; Jha, G. J.

1985-07-01

Single layer end-to-end inverted and everted techniques of entero-anastomosis were evaluated in sixteen male buffalo calves using silk and catgut sutures. All the animals of everting group showed areas of adhesion grossly, whereas it was only in three animals of inverting group. Histological evidences revealed a more uniform healing pattern in inversion group and radiography suggested comparatively greater degree of stenosis, but without functional impairment of intestinal lumen, than everting anastomosis. Connective tissue proliferation and mononuclear cell infiltrations were very minimal with silk suture whereas these were pronounced with catgut, irrespective of anastomotic technique. Thus inversion technique of anastomosis accomplished by single layer suturing with silk thread was ideal for enteroanastomosis in cattle.

Torsion of monofilament and polyfilament sutures under tension decreases suture strength and increases risk of suture fracture.

LENUS (Irish Health Repository)

Hennessey, D B

2012-08-01

A continuous running suture is the preferential method for abdominal closure. In this technique the suture is secured with an initial knot and successive tissue bites are taken. At each tissue bite, the needle is rotated through the tissue; in doing so, the suture can twist around the knot which acts as an anchor.

A comparison of simple continuous versus simple interrupted suture patterns for tracheal anastomosis after large-segment tracheal resection in dogs.

Science.gov (United States)

Fingland, R B; Layton, C I; Kennedy, G A; Galland, J C

1995-01-01

Two suture techniques for tracheal anastomosis after large-segment tracheal resection were compared. Eight cartilages were resected from the trachea of each of 12 dogs; anastomoses with 4-0 polydioxanone suture were created using a simple continuous suture technique in six dogs and a simple interrupted suture technique in six dogs. Surgical time was shorter but apposition of tracheal segments at the time of surgery was less precise with the simple continuous suture technique. The dogs were evaluated for 150 days after surgery. Clinical abnormalities after tracheal resection and anastomosis were not observed. Percent dorsoventral luminal stenosis was calculated by measuring the tracheal lumen diameter on lateral cervical radiographs. Percent luminal stenosis was calculated planimetrically using a computerized digitizing tablet. Anastomotic stenosis was mild in all dogs; however, the mean percent.luminal stenosis determined planimetrically was significantly greater for dogs that had the simple continuous suture technique. Planimetric measurements of cross-sectional area made before and after formalin fixation were not significantly different. Radiographic determination of percent dorsoventral luminal stenosis was a poor predictor of diminution of cross-sectional area determined planimetrically.

Comparison of a continuous suture pattern with a simple interrupted pattern for enteric closure in dogs and cats: 83 cases (1991-1997).

Science.gov (United States)

Weisman, D L; Smeak, D D; Birchard, S J; Zweigart, S L

1999-05-15

To describe and compare a simple continuous suture pattern with a simple interrupted pattern for enterotomy closure or end-to-end intestinal anastomosis. Retrospective study. 58 dogs and 25 cats that underwent enterotomy or intestinal resection and anastomosis. Signalment, surgical procedure, suture pattern, suture material, confirmation of dehiscence, and follow-up were reviewed. Groups were compared by procedure (anastomosis or enterotomy) and by suture pattern. 57 animals underwent continuous closure; 26 had interrupted closure. Only polydioxanone or polypropylene suture materials were used. Overall, 81 (98%) animals had no signs of intestinal dehiscence and survived > 2 weeks. Two animals had confirmed dehiscence after foreign body removal, 1 of 57 (2%) after continuous closure, and 1 of 26 (4%) after interrupted closure. The simple continuous closure pattern is an acceptable alternative to simple interrupted closure for small intestinal anastomosis or enterotomy closure.

COMPARISON OF ABSORBABLE EXTRA LONG TERM POLY HYDROXY BUTYRATE SUTURE VS NON ABSORBABLE (POLYPROPYLENE SUTURE FOR ABDOMINAL WALL CLOSURE

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Mallikarjun

2015-07-01

Full Text Available PURPOSE: The aim of study is to compare Continuous technique with non - absorbable sutures, Interrupted technique with non - absorbable sutures and Continuous technique with slowly absorbable sutures Focusing mainly on incidence of incisional hernias, burst abdomen, wound infections, chronic wound pain, suture sinus, stitch granuloma, time for rectus closure. METHODOLOGY : Study was conducted for a period of one year on 271 randomized patients with primary elective midline laparotomy in our hospital . patients are divided into group I includes 102 patients with continuous technique using non absorbable polypropylene, group II includes 91 patients with interrupted technique using non absorbable polypropylene and group III includes 78 patients with continuous slowly absorbable polyhydroxybutyrate. RESULTS: No significant difference observed in incidence of wound infections and burst abdomen in all the 3 groups but relatively higher incidence of wound infections in noted our hospital. Incidence of stich granuloma suture sinus and chronic wound pain is more with interrupted technique than continuous technique and are more with non - absor bable suture material. CONCLUSION: Incidence of incisional hernias, suture complications like suture sinus, stitch granuloma can be more effectively reduced with slowly absorbable continuous sutures.

Knotless single-row rotator cuff repair: a comparative biomechanical study of 2 knotless suture anchors.

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Efird, Chad; Traub, Shaun; Baldini, Todd; Rioux-Forker, Dana; Spalazzi, Jeffrey P; Davisson, Twana; Hawkins, Monica; McCarty, Eric

2013-08-01

The purpose of this study was to compare the gap formation during cyclic loading, maximum repair strength, and failure mode of single-row full-thickness supraspinatus repairs performed using 2 knotless suture anchors with differing internal suture-retention mechanisms in a human cadaver model. Nine matched pairs of cadaver shoulders were used. Full-thickness tears were induced by detaching the supraspinatus tendon from the greater tuberosity. Single-row repairs were performed with either type I (Opus Magnum PI; ArthroCare, Austin, Texas) or type II (ReelX STT; Stryker, Mahwah, New Jersey) knotless suture anchors. The repaired tendon was cycled from 10 to 90 N for 500 cycles, followed by load to failure. Gap formation was measured at 5, 100, 200, 300, 400, and 500 cycles with a video digitizing system. Anchor type or location (anterior or posterior) had no effect on gap formation during cyclic loading regardless of position (anterior, P=.385; posterior, P=.389). Maximum load to failure was significantly greater (P=.018) for repairs performed with type II anchors (288±62 N) compared with type I anchors (179±39 N). Primary failure modes were anchor pullout and tendon tearing for type II anchors and suture slippage through the anchor for type I anchors. The internal ratcheting suture-retention mechanism of type II anchors may have helped this anchor outperform the suture-cinching mechanism of type I anchors by supporting significantly higher loads before failure and minimizing suture slippage, potentially leading to stronger repairs clinically. Copyright 2013, SLACK Incorporated.

Mechanics of Suture Joints

Science.gov (United States)

Li, Yaning; Song, Juha; Ortiz, Christine; Boyce, Mary; Ortiz Group/DMSE/MIT Team; Boyce Group/ME/MIT Team

2011-03-01

Biological sutures are joints which connect two stiff skeletal or skeletal-like components. These joints possess a wavy geometry with a thin organic layer providing adhesion. Examples of biological sutures include mammalian skulls, the pelvic assembly of the armored fish Gasterosteus aculeatus (the three-spined stickleback), and the suture joints in the shell of the red-eared slider turtle. Biological sutures allow for movement and compliance, control stress concentrations, transmit loads, reduce fatigue stress and absorb energy. In this investigation, the mechanics of the role of suture geometry in providing a naturally optimized joint is explored. In particular, analytical and numerical micromechanical models of the suture joint are constructed. The anisotropic mechanical stiffness and strength are studied as a function of suture wavelength, amplitude and the material properties of the skeletal and organic components, revealing key insights into the optimized nature of these ubiquitous natural joints.

Novel Technique to Overcome the Nonavailability of a Long Needle 9-0 Polypropylene Suture for Sutured Scleral Fixation of the Posterior Chamber Intraocular Lens Using a Single Fisherman's Knot.

Science.gov (United States)

Shin, Yong Un; Seong, Mincheol; Cho, Hee Yoon; Kang, Min Ho

2017-01-01

To describe a method to overcome the nonavailability of a long needle 9-0 polypropylene suture for sutured scleral fixation of the posterior chamber intraocular lens (PC-IOL) using a single fisherman's knot (SFK). First, a 10-0 polypropylene suture was passed from the sclera to the ciliary sulcus using a long needle. A 9-0 suture was tied to the unpassed portion of the 10-0 suture with an SFK. We pulled the 10-0 suture to pass the SFK through the sclera, and then we cut the knot and removed the 10-0 suture. IOL fixation with 9-0 sutures used the conventional techniques used for sutured scleral-fixated IOL. Preoperative and postoperative visual acuity, corneal astigmatism, and endothelial cell count and intraoperative/postoperative complications were evaluated. An SFK joining the two sutures was passed through the sclera without breakage or slippage. A total of 35 eyes from 35 patients who underwent sutured scleral fixation of the IOL. An intraoperative complication (minor intraocular hemorrhage) was recorded in four cases. Knot exposure, IOL dislocation, subluxation, and retinal detachment were not observed. The SFK offers the opportunity to use 9-0 sutures for the long-term safety and may not require the surgeon to learn any new technique.

Suture Coding: A Novel Educational Guide for Suture Patterns.

Science.gov (United States)

Gaber, Mohamed; Abdel-Wahed, Ramadan

2015-01-01

This study aims to provide a helpful guide to perform tissue suturing successfully using suture coding-a method for identification of suture patterns and techniques by giving full information about the method of application of each pattern using numbers and symbols. Suture coding helps construct an infrastructure for surgical suture science. It facilitates the easy understanding and learning of suturing techniques and patterns as well as detects the relationship between the different patterns. Guide points are fixed on both edges of the wound to act as a guideline to help practice suture pattern techniques. The arrangement is fixed as 1-3-5-7 and a-c-e-g on one side (whether right or left) and as 2-4-6-8 and b-d-f-h on the other side. Needle placement must start from number 1 or letter "a" and continue to follow the code till the end of the stitching. Some rules are created to be adopted for the application of suture coding. A suture trainer containing guide points that simulate the coding process is used to facilitate the learning of the coding method. (120) Is the code of simple interrupted suture pattern; (ab210) is the code of vertical mattress suture pattern, and (013465)²/3 is the code of Cushing suture pattern. (0A1) Is suggested as a surgical suture language that gives the name and type of the suture pattern used to facilitate its identification. All suture patterns known in the world should start with (0), (A), or (1). There is a relationship between 2 or more surgical patterns according to their codes. It can be concluded that every suture pattern has its own code that helps in the identification of its type, structure, and method of application. Combination between numbers and symbols helps in the understanding of suture techniques easily without complication. There are specific relationships that can be identified between different suture patterns. Coding methods facilitate suture patterns learning process. The use of suture coding can be a good

Novel Technique to Overcome the Nonavailability of a Long Needle 9-0 Polypropylene Suture for Sutured Scleral Fixation of the Posterior Chamber Intraocular Lens Using a Single Fisherman’s Knot

Directory of Open Access Journals (Sweden)

Yong Un Shin

2017-01-01

Full Text Available Purpose. To describe a method to overcome the nonavailability of a long needle 9-0 polypropylene suture for sutured scleral fixation of the posterior chamber intraocular lens (PC-IOL using a single fisherman’s knot (SFK. Methods. First, a 10-0 polypropylene suture was passed from the sclera to the ciliary sulcus using a long needle. A 9-0 suture was tied to the unpassed portion of the 10-0 suture with an SFK. We pulled the 10-0 suture to pass the SFK through the sclera, and then we cut the knot and removed the 10-0 suture. IOL fixation with 9-0 sutures used the conventional techniques used for sutured scleral-fixated IOL. Preoperative and postoperative visual acuity, corneal astigmatism, and endothelial cell count and intraoperative/postoperative complications were evaluated. Results. An SFK joining the two sutures was passed through the sclera without breakage or slippage. A total of 35 eyes from 35 patients who underwent sutured scleral fixation of the IOL. An intraoperative complication (minor intraocular hemorrhage was recorded in four cases. Knot exposure, IOL dislocation, subluxation, and retinal detachment were not observed. Conclusions. The SFK offers the opportunity to use 9-0 sutures for the long-term safety and may not require the surgeon to learn any new technique.

Triple-Loaded Suture Anchors Versus a Knotless Rip Stop Construct in a Single-Row Rotator Cuff Repair Model.

Science.gov (United States)

Noyes, Matthew P; Lederman, Evan; Adams, Christopher R; Denard, Patrick J

2018-05-01

To compare the biomechanical properties of single-row repair with triple-loaded (TL) anchor repair versus a knotless rip stop (KRS) repair in a rotator cuff repair model. Rotator cuff tears were created in 8 cadaveric matched-pair specimens and repaired with a TL anchor or KRS construct. In the TL construct, anchors were placed in the greater tuberosity and then all suture limbs were passed through the rotator cuff as simple sutures and tied. In the KRS construct, a 2-mm suture tape was passed through the tendon in an inverted mattress fashion, and a free suture was passed medial to the suture tape to create a rip-stop. Then, the suture tape and free suture were secured with knotless anchors. Displacement was observed with video tracking after cyclic loading, and specimens were loaded to failure. The mean load to failure was 438 ± 59 N in TL anchor repairs compared with 457 ± 110 N in KRS repairs (P = .582). The mean displacement with cyclic loading was 3.8 ± 1.6 mm in TL anchor repairs versus 4.3 ± 1.8 mm in the KRS group (P = .297). Mode of failure was consistent in both groups, with 6 of 8 failures in the TL anchor group and 7 of 8 failures in KRS group occurring from anchor pullout. There is no statistical difference in load to failure and cyclic loading between TL anchor and KRS single-row repair techniques. KRS repair technique may be an alternative method of repairing full-thickness supraspinatus tendon tears with a single-row construct. Copyright © 2018 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Biomechanical comparison of a single-row versus double-row suture anchor technique for rotator cuff repair.

Science.gov (United States)

Kim, David H; Elattrache, Neal S; Tibone, James E; Jun, Bong-Jae; DeLaMora, Sergai N; Kvitne, Ronald S; Lee, Thay Q

2006-03-01

Reestablishment of the native footprint during rotator cuff repair has been suggested as an important criterion for optimizing healing potential and fixation strength. A double-row rotator cuff footprint repair will demonstrate superior biomechanical properties compared with a single-row repair. Controlled laboratory study. In 9 matched pairs of fresh-frozen cadaveric shoulders, the supraspinatus tendon from 1 shoulder was repaired with a double-row suture anchor technique: 2 medial anchors with horizontal mattress sutures and 2 lateral anchors with simple sutures. The tendon from the contralateral shoulder was repaired using a single lateral row of 2 anchors with simple sutures. Each specimen underwent cyclic loading from 10 to 180 N for 200 cycles, followed by tensile testing to failure. Gap formation and strain over the footprint area were measured using a video digitizing system; stiffness and failure load were determined from testing machine data. Gap formation for the double-row repair was significantly smaller (P row repair for the first cycle (1.67 +/- 0.75 mm vs 3.10 +/- 1.67 mm, respectively) and the last cycle (3.58 +/- 2.59 mm vs 7.64 +/- 3.74 mm, respectively). The initial strain over the footprint area for the double-row repair was nearly one third (P row repair. Adding a medial row of anchors increased the stiffness of the repair by 46% and the ultimate failure load by 48% (P row repair improved initial strength and stiffness and decreased gap formation and strain over the footprint when compared with a single-row repair. To achieve maximal initial fixation strength and minimal gap formation for rotator cuff repair, reconstructing the footprint attachment with 2 rows of suture anchors should be considered.

[An experimental assessment of methods for applying intestinal sutures in intestinal obstruction].

Science.gov (United States)

Akhmadudinov, M G

1992-04-01

The results of various methods used in applying intestinal sutures in obturation were studied. Three series of experiments were conducted on 30 dogs--resection of the intestine after obstruction with the formation of anastomoses by means of double-row suture (Albert--Shmiden--Lambert) in the first series (10 dogs), by a single-row suture after V. M. Mateshchuk [correction of Mateshuku] in the second series, and bu a single-row stretching suture suggested by the author in the third series. The postoperative complications and the parameters of physical airtightness of the intestinal anastomosis were studied in dynamics in the experimental animals. The results of the study: incompetence of the anastomosis sutures in the first series 6, in the second 4, and in the third series one. Adhesions occurred in all animals of the first and second series and in 2 of the third series. Six dogs of the first series died, 4 of the second, and one of the third. Study of the dynamics of the results showed a direct connection of the complications with the parameters of the physical airtightness of the anastomosis, and the last-named with the method of the intestinal suture. Relatively better results were noted in formation of the anastomosis by means of our suggested stretshing continuous suture passed through the serous, muscular, and submucous coats of the intestine.

Two Techniques of Intestinal Wall Suture in Surgical Treatment of Ileus in Dogs and the Importance of Omentalisation

Directory of Open Access Journals (Sweden)

M. Crha

2008-01-01

Full Text Available Model experimental studies focused on the intestinal suture techniques in relation to healing, postoperative narrowing of the intestinal lumen or adhesion formation can not comprise a number of clinical factors (foreign body presence in the intestine, haematological abnormalities, septic peritonitis, different age of patients, etc. that under clinical practice conditions may have an effect on the healing of the intestinal suture. The aim of this clinical study was to confirm in a group of dogs surgically treated for small bowel obstruction, whether different techniques of its wall suture may affect the frequency of possible dehiscence occurrence. This study compares two different techniques of intestinal wall suture in relation to postoperative dehiscence of the intestinal wall closure. Based on the clinical observation with regard to the risk of postoperative dehiscence and possible complications in form of adhesions, also the importance of omentalisation in the suture of small bowel was evaluated. No significant difference was demonstrated (p > 0.05 in the frequency of postoperative dehiscence at the site of the intestinal wall closure between the two-layer inverting and singlelayer appositional techniques of suture. Likewise, no significant difference was demonstrated (p > 0.05 in the frequency of dehiscence of intestinal wall suture between patients that underwent intestinal suture omentalisation and those whose intestinal wall suture was not complemented with omentalisation. Based on the results of this clinical study it may be stated that both manual single-layer approximation technique and two-layer inverting technique of the intestinal wall suture are equally safe from the viewpoint of possible dehiscence, and it depends on the surgeon's preference, which one of the said techniques he or she chooses. Concurrently it may be assumed that an exactly performed suture of the intestinal wall does not necessarily require omentalisation.

Feasibility of pure EFTR using an innovative new endoscopic suturing device: the Double-arm-bar Suturing System (with video).

Science.gov (United States)

Mori, Hirohito; Kobara, Hideki; Fujihara, Shintaro; Nishiyama, Noriko; Rafiq, Kazi; Oryu, Makoto; Fujiwara, Masao; Suzuki, Yasuyuki; Masaki, Tsutomu

2014-02-01

Endoscopic full-thickness resection (EFTR) requires a reliable full-thickness suturing device and an endoscopic counter-traction device to prevent the collapse of the digestive tract. The present study aimed to assess the reliability of newly developed flexible endoscopy suturing devices and the feasibility of pure EFTR. A total of 30 EFTRs were performed and allocated to three groups (N = 10 for each group). The full-thickness sutures were placed using over-the-scope clips (OTSCs), hand-sewn sutures, or the Double-arm-bar Suturing System (DBSS). Air leak tests were conducted in the three groups. The times required for the placement of one OTSC suture and single-stitch simple interrupted sutures (hand-sewn and DBSS sutures, respectively) were also compared. All 30 full-thickness sutures were completely and successfully placed. Regarding the air leak tests, the Mann-Whitney U test showed significant differences between OTSC and hand-sewn sutures (p = 0.003). There was also a significant difference between OTSC and DBSS sutures (p = 0.023). There was no significant difference between hand-sewn and DBSS sutures (p = 0.542). A significant difference was found in the suture time for single-stitch simple interrupted sutures among the OTSC, hand-sewn, and DBSS sutures. The Mann-Whitney U test revealed a significant difference between OTSC and hand-sewn sutures (p = 0.0001). There was no significant difference between OTSC and DBSS sutures (p = 0.533), while a significant difference was found between hand-sewn and DBSS sutures (p = 0.0001). Pure EFTR is feasible if the mechanical counter traction system is used to expand a small operative field and DBSS is used to make full-thickness sutures. The high safety of full-thickness resection and full-thickness suturing allows for clinical applications of this method.

Comparable biomechanical results for a modified single-row rotator cuff reconstruction using triple-loaded suture anchors versus a suture-bridging double-row repair.

Science.gov (United States)

Lorbach, Olaf; Kieb, Matthias; Raber, Florian; Busch, Lüder C; Kohn, Dieter; Pape, Dietrich

2012-02-01

To compare the biomechanical properties and footprint coverage of a single-row (SR) repair using a modified suture configuration versus a double-row (DR) suture-bridge repair in small to medium and medium to large rotator cuff tears. We created 25- and 35-mm artificial defects in the rotator cuff of 24 human cadaveric shoulders. The reconstructions were performed as either an SR repair with triple-loaded suture anchors (2 to 3 anchors) and a modified suture configuration or a modified suture-bridge DR repair (4 to 6 anchors). Reconstructions were cyclically loaded from 10 to 60 N. The load was increased stepwise up to 100, 180, and 250 N. Cyclic displacement and load to failure were determined. Furthermore, footprint widths were quantified. In the 25-mm rupture, ultimate load to failure was 533 ± 107 N for the SR repair and 681 ± 250 N for the DR technique (P ≥ .21). In the 35-mm tear, ultimate load to failure was 792 ± 122 N for the SR reconstruction and 891 ± 174 N for the DR reconstruction (P ≥ .28). There were no statistically significant differences for both tested rupture sizes. Cyclic displacement showed no significant differences between the tested configurations at 60 N (P = .563), 100 N (P = .171), 180 N (P = .211), and 250 N (P = .478) for the 25-mm tear. For the 35-mm tear, cyclic displacement showed significantly lower gap formation for the SR reconstruction at 180 N (P = .037) and 250 N (P = .020). No significant differences were found at 60 N (P = .296) and 100 N (P = .077). A significantly greater footprint width (P = .028) was seen for the DR repair (16.2 mm) compared with the SR repair (13.8 mm). However, both reconstructions were able to achieve complete footprint coverage compared with the initial footprint. The tested SR repair using a modified suture configuration was similar in load to failure and cyclic displacement to the DR suture-bridge technique independent of the tested initial sizes of the rupture. The tested DR repair

[Single-layer colonic anastomoses using polyglyconate (Maxon) vs. two-layer anastomoses using chromic catgut and silk. Experimental study].

Science.gov (United States)

García-Osogobio, Sandra Minerva; Takahashi-Monroy, Takeshi; Velasco, Liliana; Gaxiola, Miguel; Sotres-Vega, Avelina; Santillán-Doherty, Patricio

2006-01-01

The safety of an intestinal anastomosis is usually measured by its complication rate, especially the incidence of anastomotic leakage. A wide variety of methods have been described to reestablish intestinal continuity including single-layer continuous or two-layer interrupted anastomosis. To evaluate if the single-layer continuous anastomosis using polygluconate is safer and reliable than two-layer interrupted anastomosis with chromic catgut and silk. A prospective, experimental, randomized and comparative analysis was conducted in 20 dogs. They were divided in two groups; group 1 underwent two-layer interrupted anastomosis and group 2 underwent sigle-layer continuous technique. Anastomoses were timed. Both groups were under observation. Anastomotic leakage, and other complications were evaluated. The animals were sacrified and the anastomosis was taken out together with 10 cm of colon on both sides of the anastomosis. Breaking strength, histologic evaluation and hydroxyproline determination were performed. Ten two-layer anastomosis and ten single-layer anastomosis were performed. A median of 25 minutes (range: 20-30 minutes) was required to construct the anastomoses in group 1 versus 20 minutes (range: 12-25 minutes) in group 2. All animals survived and no leakage was observed. Wound infection ocurred in four dogs (20%). Median breaking strength was 230 mm Hg in group 1 and 210 mm Hg in group 2. Hydroxyproline concentration was 8.94 mg/g in group 1 (range: 5.33-16.71) and 9.94 mg/g in group 2 (range: 2.96-21.87). There was no difference among groups about the inflammatory response evaluated by pathology. There was no statistical significance in any variable evaluated. CONCLUIONS: This study demonstrates that a single-layer continuous is similar in terms of safety to the two-layer technique, but because of its facility to perform, the single-layer technique could be superior.

Comparison of functional results of two fixation systems using single-row suturing of rotator cuff.

Science.gov (United States)

Muniesa-Herrero, M P; Torres-Campos, A; Urgel-Granados, A; Blanco-Llorca, J A; Floría-Arnal, L J; Roncal-Boj, J C; Castro-Sauras, A

Arthroscopic repair of rotator cuff disorders is a technically demanding but successful procedure. Many anchor and suture alternatives are now available. The choice of the implant by the surgeon is less important than the configuration of the suture used to fix the tendon, however it is necessary to know if there are differences in the results, using each one of them. The aim of the study is to evaluate if there are differences between the knotted and non-knotted implant in terms of functional and satisfaction results. A retrospective study was carried out on 83 patients operated between 2010 and 2014 in our center using 2anchoring systems with and without knotting (39 versus 44 patients respectively), with single row in complete rupture of the rotator cuff. At the end of the follow-up, an average score was obtained on the Constant scale of 74.6 points. 98% of the patients considered the result of the surgery satisfactory. Statistically, there were no significant differences between the 2groups in terms of functionality, satisfaction or reincorporation to activities. The functional results of the single-row cuff suture are satisfactory, although biomechanical studies show advantages in favor of sutures that reproduce a transoseo system. It our series of patients the presence of knotting does not show per se a significant functional difference being both superimposable techniques in absolute values of functionality and patient satisfaction. Copyright © 2018 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

Nuevo método de sutura subcutánea percutánea continua New method of continuous percutaneous subcutaneous suture

Directory of Open Access Journals (Sweden)

Germán Brito Sosa

2012-06-01

Full Text Available Objetivos: realizar un método de sutura continua, en las personas operadas en el Hospital "Julio Trigo López", que disminuya los granulomas a nivel de la herida quirúrgica, y compararlas con el método tradicional. Métodos: se realizó un estudio experimental sobre la aplicación de un método de sutura subcutánea percutánea continua, en un grupo de pacientes operados de diversas enfermedades, ya sea de urgencia, electivo o ambulatorio, en el Hospital "Julio Trigo López", en los años 2008 y 2009. Resultados: con el método de sutura subcutánea percutánea continua con nylon no se forman granulomas, mientras que con el método tradicional, sí ocurre en un porcentaje no despreciable. Las ventajas del método de sutura subcutánea percutánea continua con nylon son: en el plano celular subcutáneo de la pared abdominal no queda sutura, no se producen granulomas y es más económica. Conclusiones: la sutura de nylon es menos rechazada que la del cromado, ya que no se producen granulomas. El método de sutura subcutánea percutánea continua es una sutura más hemostática que el método tradicional, ya que el por ciento de hematomas es menor. El gasto económico es menor con el método de sutura subcutánea percutánea continua. Con el método de sutura subcutánea percutánea continua la sutura es extraída al 10mo. día de haberla aplicado.Objectives: to apply a continuous suture method to reduce granulomas in surgical wounds in patients operated on at "Julio Trigo Lopez" hospital, and to compare the results with those of the traditional method. Methods: an experimental study was conducted on the application of a continuous percutaneous subcutaneous suture in a group of patients operated on from several diseases, either under emergency, elective or outpatient conditions at "Julio Trigo Lopez" hospital during 2008 and 2009. Results: the continuous percutaneous subcutaneous suture method with nylon prevents formation of granulomas, whereas

A retrospective study comparing the outcome of horses undergoing small intestinal resection and anastomosis with a single layer (Lembert) or double layer (simple continuous and Cushing) technique.

Science.gov (United States)

Close, Kristyn; Epstein, Kira L; Sherlock, Ceri E

2014-05-01

To (1) compare postoperative complications and survival in horses after small intestinal resection and anastomosis using 2 anastomosis techniques (single layer Lembert; double layer simple continuous oversewn with Cushing), and (2) to compare outcome by anastomosis type (jejunoileostomy; jejunojejunostomy). Retrospective case series. Horses (n = 53). Medical records (July 2006-July 2010) of all horses that had small intestinal resection and anastomosis. Horses were divided into groups based on technique and type of anastomosis. Comparisons of pre- and intraoperative findings (disease severity), postoperative complications, and survival rates were made between groups. There were no differences in disease severity, postoperative complications, or survival between single layer (n = 23) or double layer (n = 31) anastomoses. There were no differences in disease severity or survival between jejunoileostomy (n = 16) or jejunojejunostomy (n = 38). There was a higher incidence of postoperative colic in hospital after jejunoileostomy (13/16) compared with jejunojejunostomy (18/38) (P = .0127). Postoperative complications and survival are comparable between horses undergoing single layer and double layer small intestinal end-to-end anastomoses. With the exception of increased postoperative colic in the hospital, postoperative complications and survival after jejunoileostomy and jejunojejunostomy are also comparable. © Copyright 2014 by The American College of Veterinary Surgeons.

Current manufacturing processes of drug-eluting sutures.

Science.gov (United States)

Champeau, Mathilde; Thomassin, Jean-Michel; Tassaing, Thierry; Jérôme, Christine

2017-11-01

Drug-eluting sutures represent the next generation of surgical sutures since they fulfill their mechanical functions but also deliver the drug in their vicinity after implantation. These implants are produced by a variety of manufacturing processes. Drug-eluting sutures represent the next generation of surgical sutures since they fulfill their mechanical functions but also deliver the drug in their vicinity after implantation. These implants are produced by a variety of manufacturing processes. Two general approaches can be followed: (i) the ones that add the API into the material during the manufacturing process of the suture and (ii) the ones that load the API to an already manufactured suture. Areas covered: This review provides an overview of the current manufacturing processes for drug-eluting suture production and discusses their benefits and drawbacks depending on the type of drugs. The mechanical properties and the drug delivery profile of drug-eluting sutures are highlighted since these implants must fulfill both criteria. Expert opinion: For limited drug contents, melt extrusion and electrospinning are the emerging processes since the drug is added during the suture manufacture process. Advantageously, the drug release profile can be tuned by controlling the processing parameters specific to each process and the composition of the drug-containing polymer. If high drug content is targeted, the coating or grafting of a drug layer on a pre-manufactured suture allows for preservation of the tensile strength requirements of the suture.

On the roentgenomorphological correlations of cranial sutures

International Nuclear Information System (INIS)

Verkhoglyadova, T.P.; Koval', G.Yu.; Shuaa, T.I.

1986-01-01

The authors explain the essence of the zone of excessive transparence along the cranial sutures visualized on the X-ray pictures during the first year of life by presence of large number of rough-fiber bone in the marginal regions. The zone of ''physiological sclerosis'' is postulated as a result of summation of the bone margin shadows consisting of compact substance (osteones). Microscopic examination of skull in brain tumors revealed a delay in the formation of bone margins in the suture region with an excessive amount of connective and osteoid tissue while in craniostenosis closure of cranial sutures being with intensive bone formation as well as by closure of the bone margins by newly formed bone tissue around the vessels of the connective layer of the suture

Influence of suture technique and suture material selection on the mechanics of end-to-end and end-to-side anastomoses.

Science.gov (United States)

Baumgartner, N; Dobrin, P B; Morasch, M; Dong, Q S; Mrkvicka, R

1996-05-01

Experiments were performed in dogs to evaluate the mechanics of 26 end-to-end and 42 end-to-side artery-vein graft anastomoses constructed with continuous polypropylene sutures (Surgilene; Davis & Geck, Division of American Cyanamid Co., Danbury, Conn.), continuous polybutester sutures (Novafil; Davis & Geck), and interrupted stitches with either suture material. After construction, the grafts and adjoining arteries were excised, mounted in vitro at in situ length, filled with a dilute barium sulfate suspension, and pressurized in 25 mm Hg steps up to 200 mm Hg. Radiographs were obtained at each pressure. The computed cross-sectional areas of the anastomoses were compared with those of the native arteries at corresponding pressures. Results showed that for the end-to-end anastomoses at 100 mm Hg the cross-sectional areas of the continuous Surgilene anastomoses were 70% of the native artery cross-sectional areas, the cross-sectional areas of the continuous Novafil anastomoses were 90% of the native artery cross-sectional areas, and the cross-sectional areas of the interrupted anastomoses were 107% of the native artery cross-sectional areas (p anastomoses demonstrated no differences in cross-sectional areas or compliance for the three suture techniques. This suggests that, unlike with end-to-end anastomoses, when constructing an end-to-side anastomosis in patients any of the three suture techniques may be acceptable.

A single centre comparative study of laparoscopic mesh rectopexy versus suture rectopexy

Directory of Open Access Journals (Sweden)

Manash Ranjan Sahoo

2014-01-01

Full Text Available Aim: The aim of our study is to compare the results of laparoscopic mesh vs. suture rectopexy. Materials and Methods: In this retrospective study, 70 patients including both male and female of age ranging between 20 years and 65 years (mean 42.5 yrs were subjected to laparoscopic rectopexy during the period between March 2007 and June 2012, of which 38 patients underwent laparoscopic mesh rectopexy and 32 patients laparoscopic suture rectopexy. These patients were followed up for a mean period of 12 months assessing first bowel movement, hospital stay, duration of surgery, faecal incontinence, constipation, recurrence and morbidity. Results: Duration of surgery was 100.8 ± 12.4 minutes in laparoscopic suture rectopexy and 120 ± 10.8 min in laparoscopic mesh rectopexy. Postoperatively, the mean time for the first bowel movement was 38 hrs and 40 hrs, respectively, for suture and mesh rectopexy. Mean hospital stay was five (range: 4-7 days. There was no significant postoperative complication except for one port site infection in mesh rectopexy group. Patients who had varying degree of incontinence preoperatively showed improvement after surgery. Eleven out of 18 (61.1% patients who underwent laparoscopic suture rectopexy as compared to nine of 19 (47.3% patients who underwent laparoscopic mesh rectopexy improved as regards constipation after surgery. Conclusion: There were no significant difference in both groups who underwent surgery except for patients undergoing suture rectopexy had better symptomatic improvement of continence and constipation. Also, cost of mesh used in laparoscopic mesh rectopexy is absent in lap suture rectopexy group. To conclude that laparoscopic suture rectopexy is a safe and feasible procedure and have comparable results as regards operative time, morbidity, bowel function, cost and recurrence or even slightly better results than mesh rectopexy.

Ultrasound evaluation of arthroscopic full-thickness supraspinatus rotator cuff repair: single-row versus double-row suture bridge (transosseous equivalent) fixation. Results of a prospective, randomized study.

Science.gov (United States)

Gartsman, Gary M; Drake, Gregory; Edwards, T Bradley; Elkousy, Hussein A; Hammerman, Steven M; O'Connor, Daniel P; Press, Cyrus M

2013-11-01

The purpose of this study was to compare the structural outcomes of a single-row rotator cuff repair and double-row suture bridge fixation after arthroscopic repair of a full-thickness supraspinatus rotator cuff tear. We evaluated with diagnostic ultrasound a consecutive series of ninety shoulders in ninety patients with full-thickness supraspinatus tears at an average of 10 months (range, 6-12) after operation. A single surgeon at a single hospital performed the repairs. Inclusion criteria were full-thickness supraspinatus tears less than 25 mm in their anterior to posterior dimension. Exclusion criteria were prior operations on the shoulder, partial thickness tears, subscapularis tears, infraspinatus tears, combined supraspinatus and infraspinatus repairs and irreparable supraspinatus tears. Forty-three shoulders were repaired with single-row technique and 47 shoulders with double-row suture bridge technique. Postoperative rehabilitation was identical for both groups. Ultrasound criteria for healed repair included visualization of a tendon with normal thickness and length, and a negative compression test. Eighty-three patients were available for ultrasound examination (40 single-row and 43 suture-bridge). Thirty of 40 patients (75%) with single-row repair demonstrated a healed rotator cuff repair compared to 40/43 (93%) patients with suture-bridge repair (P = .024). Arthroscopic double-row suture bridge repair (transosseous equivalent) of an isolated supraspinatus rotator cuff tear resulted in a significantly higher tendon healing rate (as determined by ultrasound examination) when compared to arthroscopic single-row repair. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Biomechanical comparison of double-row versus transtendon single-row suture anchor technique for repair of the grade III partial articular-sided rotator cuff tears.

Science.gov (United States)

Zhang, Chun-Gang; Zhao, De-Wei; Wang, Wei-Ming; Ren, Ming-Fa; Li, Rui-Xin; Yang, Sheng; Liu, Yu-Peng

2010-11-01

For partial-thickness tears of the rotator cuff, double-row fixation and transtendon single-row fixation restore insertion site anatomy, with excellent results. We compared the biomechanical properties of double-row and transtendon single-row suture anchor techniques for repair of grade III partial articular-sided rotator cuff tears. In 10 matched pairs of fresh-frozen sheep shoulders, the infraspinatus tendon from 1 shoulder was repaired with a double-row suture anchor technique. This comprised placement of 2 medial anchors with horizontal mattress sutures at an angle of ≤ 45° into the medial margin of the infraspinatus footprint, just lateral to the articular surface, and 2 lateral anchors with horizontal mattress sutures. Standardized, 50% partial, articular-sided infraspinatus lesions were created in the contralateral shoulder. The infraspinatus tendon from the contralateral shoulder was repaired using two anchors with transtendon single-row mattress sutures. Each specimen underwent cyclic loading from 10 to 100 N for 50 cycles, followed by tensile testing to failure. Gap formation and strain over the footprint area were measured using a motion capture system; stiffness and failure load were determined from testing data. Gap formation for the transtendon single-row repair was significantly smaller (P row repair for the first cycle ((1.74 ± 0.38) mm vs. (2.86 ± 0.46) mm, respectively) and the last cycle ((3.77 ± 0.45) mm vs. (5.89 ± 0.61) mm, respectively). The strain over the footprint area for the transtendon single-row repair was significantly smaller (P row repair. Also, it had a higher mean ultimate tensile load and stiffness. For grade III partial articular-sided rotator cuff tears, transtendon single-row fixation exhibited superior biomechanical properties when compared with double-row fixation.

A biomechanical analysis of a single-row suture anchor fixation of a large bony bankart lesion.

Science.gov (United States)

Dyskin, Evgeny; Marzo, John M; Howard, Craig; Ehrensberger, Mark

2014-12-01

This study was conducted to assess whether a single-row suture anchor repair of a bony Bankart lesion comprising 19% of the glenoid length restores peak translational force and glenoid depth compared with the intact shoulder. Nine thawed adult cadaveric shoulders were dissected and mounted in 45° of abduction and 30° of external rotation. A bony Bankart lesion was simulated with an anterior longitudinal osteotomy, parallel to the superoinferior axis of the glenoid, equivalent to 19% of the glenoid length. The humeral head was displaced 10 mm anteriorly at a speed of 2 mm/s with a 50-N compressive load applied. Testing was performed with the glenoid intact, a simulated lesion, and the lesion repaired with 3 single-row suture anchors. Median (interquartile range [IQR]) peak translational force and glenoid depth were reported. The Friedman test and post hoc comparisons with the Wilcoxon signed rank test were used for between-group analyses. Peak translational force decreased after osteotomy (13.7 N; IQR, 9.6 to 15.5 N; P = .01) and increased after the repair (18.3 N; IQR, 18.3 to 20.6 N; P = .01) compared with the intact shoulder (23.7 N; IQR, 16.4 to 29.9 N). Glenoid depth significantly decreased after the osteotomy (0.2 mm; IQR, -0.6 to 0.7 mm) compared with baseline (1.7 mm; IQR, 1.3 to 2.0 mm; P = .01) and increased after repair (0.8 mm; IQR, 0.1 to 1.0 mm; P = .03) compared with the osteotomized shoulder. The glenoid depth of the repair was less than the baseline value (P = .01). Repair of an anterior bony Bankart lesion equivalent to 19% of the glenoid length with 3 suture anchors restored the peak translational force needed to anteriorly displace the humerus relative to the glenoid; however, this technique failed to restore the natural glenoid depth in a laboratory setting. Our findings describe the inability of a single-row suture anchor repair to provide anatomic fixation of the bony Bankart lesion equivalent to 19% of the glenoid length

Biomechanical advantages of triple-loaded suture anchors compared with double-row rotator cuff repairs.

Science.gov (United States)

Barber, F Alan; Herbert, Morley A; Schroeder, F Alexander; Aziz-Jacobo, Jorge; Mays, Matthew M; Rapley, Jay H

2010-03-01

To evaluate the strength and suture-tendon interface security of various suture anchors triply and doubly loaded with ultrahigh-molecular weight polyethylene-containing sutures and to evaluate the relative effectiveness of placing these anchors in a single-row or double-row arrangement by cyclic loading and then destructive testing. The infraspinatus muscle was reattached to the original humeral footprint by use of 1 of 5 different repair patterns in 40 bovine shoulders. Two single-row repairs and three double-row repairs were tested. High-strength sutures were used for all repairs. Five groups were studied: group 1, 2 triple-loaded screw suture anchors in a single row with simple stitches; group 2, 2 triple-loaded screw anchors in a single row with simple stitches over a fourth suture passed perpendicularly ("rip-stop" stitch); group 3, 2 medial and 2 lateral screw anchors with a single vertical mattress stitch passed from the medial anchors and 2 simple stitches passed from the lateral anchors; group 4, 2 medial double-loaded screw anchors tied in 2 mattress stitches and 2 push-in lateral anchors capturing the medial sutures in a "crisscross" spanning stitch; and group 5, 2 medial double-loaded screw anchors tied in 2 mattress stitches and 2 push-in lateral anchors creating a "suture-bridge" stitch. The specimens were cycled between 10 and 180 N at 1.0 Hz for 3,500 cycles or until failure. Endpoints were cyclic loading displacement (5 and 10 mm), total displacement, and ultimate failure load. A single row of triply loaded anchors was more resistant to stretching to a 5- and 10-mm gap than the double-row repairs with or without the addition of a rip-stop suture (P row repair (P row created by 2 medial double-loaded suture anchors and 2 lateral push-in anchors stretched more than any other group (P row repairs with either crossing sutures or 4 separate anchor points were more likely to fail (5- or 10-mm gap) than a single-row repair loaded with 3 simple sutures

Evaluation of cesarean scar after single- and double-layer hysterotomy closure: a prospective cross-sectional study.

Science.gov (United States)

Tekiner, Nur Betül; Çetin, Berna Aslan; Türkgeldi, Lale Susan; Yılmaz, Gökçe; Polat, İbrahim; Gedikbaşı, Ali

2018-05-01

We aimed to determine if there is a difference in the size of the cesarean scar defect using saline infusion sonography (SIS) performed on the postoperative third month in patients who underwent single- or double-layered unlocked closure of their uterine incision during their first cesarean delivery. This study was conducted as a prospective cross-sectional study between February 2015 and January 2016 in patients admitted to the labour ward of the Kanuni Sultan Suleyman Training and Research Hospital who subsequently underwent their first delivery by cesarean section. Patients with a previous history of cesarean delivery, preterm pregnancies less than 34 gestational weeks, patients lost to follow-up or those who had an IUD inserted after delivery were excluded from the study. Out of the 327 patients who underwent primary cesarean delivery, 280 were included into the study. Patients were divided into two groups according to the single- (n:126) or double-layered (n:156) closure of their uterine incision. The maternal age, height, weight, obstetric and gynecologic histories, medical histories, indications for their cesarean delivery, technique of uterine closure, birth weight of the baby, duration of the cesarean delivery, need for extra suturing and transfusion were recorded. A Saline infusion sonography (SIS) was performed 3 months postoperatively to determine the presence, depth and length of the cesarean scar. The residual myometrial thickness overlying the scar defect and the fundal myometrial thickness were recorded. No difference was detected between the groups with respect to patient characteristics, whether the operation was elective or emergent, the type of anesthesia used, need for extra suturing, incidence of bladder injuries or uterine atony, need for blood transfusions, duration of labour or cervical dilatation and effacement between the two groups. No statistically significant difference was detected between the two groups with respect to the length

Hydraulic Stability of Single-Layer Dolos and Accropode Armour Layers

DEFF Research Database (Denmark)

Christensen, M.; Burcharth, H. F.

1995-01-01

A new design for Dolos breakwater armour layers is presented: Dolos armour units are placed in a selected geometric pattern in a single layer. A series of model tests have been performed in order to determine the stability of such single-layer Dolos armour layers. The test results are presented...... and compared to the stability formula for the traditional double-layer, randomly placed Dolos armour layer design presented by Burcharth (1992). The results of a series of stability tests performed with Accropode® armour layers is presented and compared to the test results obtained with single-layer Dolos...... armour layers. Run-up and reflection are presented for both single-layer Dolos armour and Accropode armour....

Mechanical Behavior of Bio-inspired Model Suture Joints

Science.gov (United States)

Li, Yaning; Lin, Erica; Ortiz, Christine; Boyce, Mary

2012-02-01

Suture joints of varying degrees of geometric complexity are prevalent throughout nature as a means of joining structural elements while providing locally tailored mechanical performance. Here, micromechanical models of general trapezoidal waveforms of varying hierarchy are formulated to reveal the role of geometric complexity in governing stiffness, strength, toughness and corresponding deformation and failure mechanisms. Physical constructs of model composite suture systems are fabricated via multi-material 3D printing (Object Connex500). Tensile tests are conducted on samples covering a range in geometry, thus providing quantitative measures of stiffness, strength, and failure. The experiments include direct visualization of the deformation and failure mechanisms and their progression, as well as their dependence on suture geometry, showing the interplay between shear and tension/compression of the interfacial layers and tension of the skeletal teeth and the transition in failure modes with geometry. The results provide quantitative guidelines for the design and tailoring of suture geometry to achieve the desired mechanical properties and also facilitate understanding of suture growth and fusion, and evolutionary phenotype.

Investigation of the best suture pattern to close a stuffed Christmas turkey.

Science.gov (United States)

Verwilghen, D; Busoni, V; van Galen, G; Wilke, M

Instructions on how to debone and stuff a turkey are available, but what is the best way to close it up? A randomised trial involving 15 turkeys was performed in order to evaluate skin disruption scores and cosmetic outcomes following the use of different suture patterns. Turkeys were deboned, stuffed and cooked according to guidelines of the US Department of Agriculture Food Safety and Inspection Services. After stuffing, they were randomly assigned to one of five closure groups: simple continuous Lembert; simple continuous Cushing; simple continuous Utrecht; simple continuous; or staples. Turkeys were cooked at 180 °C for two hours ensuring core temperature reached 75 °C. Suture line integrity was evaluated after removal of the sutures and the cosmetic aspect was graded. Before cooking, the Utrecht pattern and skin staples offered the best cosmetic result. After removal of the sutures, the skin remained intact only in the stapled group. All other suture patterns disrupted the skin after removal of the sutures, rendering the turkey less cosmetically appealing for serving. Closure of a stuffed turkey was best performed using skin staples to achieve the best cosmetic results. Using this technique you will be able to impress family and friends at a Christmas dinner, and finally show them your surgical skills.

Biomechanical Analysis of Suture Anchor vs Tenodesis Screw for FHL Transfer.

Science.gov (United States)

Drakos, Mark C; Gott, Michael; Karnovsky, Sydney C; Murphy, Conor I; DeSandis, Bridget A; Chinitz, Noah; Grande, Daniel; Chahine, Nadeen

2017-07-01

Chronic Achilles injury is often treated with flexor hallucis longus (FHL) tendon transfer to the calcaneus using 1 or 2 incisions. A single incision avoids the risks of extended dissections yet yields smaller grafts, which may limit fixation options. We investigated the required length of FHL autograft and biomechanical profiles for suture anchor and biotenodesis screw fixation. Single-incision FHL transfer with suture anchor or biotenodesis screw fixation to the calcaneus was performed on 20 fresh cadaveric specimens. Specimens were cyclically loaded until maximal load to failure. Length of FHL tendon harvest, ultimate load, stiffness, and mode of failure were recorded. Tendon harvest length needed for suture anchor fixation was 16.8 ± 2.1 mm vs 29.6 ± 2.4 mm for biotenodesis screw ( P = .002). Ultimate load to failure was not significantly different between groups. A significant inverse correlation existed between failure load and donor age when all specimens were pooled (ρ = -0.49, P Anchor failure occurred mostly by suture breakage (n = 8). Adequate FHL tendon length could be harvested through a single posterior incision for fixation to the calcaneus with either fixation option, but suture anchor required significantly less graft length. Stiffness, fixation strength, and load to failure were comparable between groups. An inverse correlation existed between failure load and donor age. Younger specimens with screw fixation demonstrated significantly greater failure loads. Adequate harvest length for FHL transfer could be achieved with a single posterior incision. There was no difference in strength of fixation between suture anchor and biotenodesis screw.

Laparoendoscopic single site (LESS) in vivo suturing using a magnetic anchoring and guidance system (MAGS) camera in a porcine model: impact on ergonomics and workload.

Science.gov (United States)

Yin, Gang; Han, Woong Kyu; Faddegon, Stephen; Tan, Yung Khan; Liu, Zhuo-Wei; Olweny, Ephrem O; Scott, Daniel J; Cadeddu, Jeffrey A

2013-01-01

To compare the ergonomics and workload of the surgeon during single-site suturing while using the magnetic anchoring and guidance system (MAGS) camera vs a conventional laparoscope. Seven urologic surgeons were enrolled and divided into an expert group (n=2) and a novice group (n=5) according to their laparoendoscopic single-site (LESS) experience. Each surgeon performed 2 conventional LESS and 2 MAGS camera-assisted LESS vesicostomy closures in a porcine model. A Likert scale (scoring 1-5) questionnaire assessing workload, ergonomics, technical difficulty, visualization, and needle handling, as well as a validated National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire were used to evaluate the tasks and workloads. MAGS LESS suturing was universally favored by expert and novice surgeons compared with conventional LESS in workload (3.4 vs 4.2), ergonomics (3.4 vs 4.4), technical challenge (3.3 vs 4.3), visualization (2.4 vs 3.3), and needle handling (3.1 vs 3.9 respectively; PNASA-TLX assessments found MAGS LESS suturing significantly decreased the workload in physical demand (P=.004), temporal demand (P=.017), and effort (P=.006). External instrument clashing was significantly reduced in MAGS LESS suturing (P<.001). The total operative time of MAGS LESS suturing was comparable to that of conventional LESS (P=.89). MAGS camera technology significantly decreased surgeon workload and improved ergonomics. Nevertheless, LESS suturing and knot tying remains a challenging task that requires training, regardless of which camera is used. Copyright © 2013 Elsevier Inc. All rights reserved.

Biomechanical testing of new meniscal repair techniques containing ultra high-molecular weight polyethylene suture.

Science.gov (United States)

Barber, F Alan; Herbert, Morley A; Schroeder, F Alexander; Aziz-Jacobo, Jorge; Sutker, Michael J

2009-09-01

To evaluate the biomechanical characteristics of current meniscal repair techniques containing ultra high-molecular weight polyethylene (UHMWPE) suture with and without cyclic loading. Vertical longitudinal cuts made in porcine menisci were secured with a single repair device. Noncycled and cycled (500 cycles) biomechanical tests were performed on the following groups: group 1, No. 2-0 Mersilene vertical suture (Ethicon, Somerville, NJ); group 2, No. 2-0 Orthocord vertical suture (DePuy Mitek, Westwood, MA); group 3, No. 0 Ultrabraid vertical suture (Smith & Nephew Endoscopy, Andover, MA); group 4, No. 2-0 FiberWire vertical suture (Arthrex, Naples, FL); group 5, vertically oriented mattress suture by use of an Ultra FasT-Fix device (Smith & Nephew Endoscopy) with No. 0 Ultrabraid; group 6, vertically oriented mattress suture by use of a RapidLoc A2 device (DePuy Mitek) with No. 2-0 Orthocord suture; group 7, vertically oriented stitch by use of a MaxFire device with MaxBraid PE suture (Biomet Sports Medicine, Warsaw, IN); and group 8, an obliquely oriented stitch of No. 0 UHMWPE suture inserted by use of a CrossFix device (Cayenne Medical, Scottsdale, AZ). Endpoints were failure loads, failure modes, stiffness, and cyclic displacement. Mean single-pull loads were calculated for Ultra FasT-Fix (121 N), FiberWire (110 N), MaxFire (130 N), Mersilene (84 N), Orthocord (124 N), RapidLoc A2 (86 N), CrossFix (77 N), and Ultrabraid (109 N). After 500 cyclic loads, the Orthocord (222 N) repair was stronger than the others: Ultra FasT-Fix (110 N), FiberWire (117 N), MaxFire (132 N), Mersilene (89 N), RapidLoc A2 (108 N), CrossFix (95 N), and Ultrabraid (126 N) (P Fix, RapidLoc A2, and MaxFire) were comparable to the isolated UHMWPE-containing suture repairs on single-failure load testing. UHMWPE-containing suture repairs are stronger than braided polyester suture repairs, but pure UHMWPE suture (Ultrabraid) elongated more during cycling. Orthocord suture is significantly

Ovarian Suspension With Adjustable Sutures: An Easy and Helpful Technique for Facilitating Laparoendoscopic Single-Site Gynecologic Surgery.

Science.gov (United States)

Chen, Kuo-Hu; Chen, Li-Ru; Seow, Kok-Min

2015-01-01

To describe a method of ovarian suspension with adjustable sutures (OSAS) for facilitating laparoendoscopic single-site gynecologic surgery (LESS) and to investigate the effect of OSAS on LESS. Prospective cohort study (Canadian Task Force classification: II-2). University teaching hospital. One hundred seventy-eight patients with benign 5- to 15-cm cystic ovarian tumors who underwent LESS with OSAS (suspension group, n = 90) and without OSAS (control group, n = 88). For patients who underwent OSAS (suspension group), 1 end of double-head straight needles with a polypropylene suture was inserted into the pelvic cavity through the abdominal skin to penetrate the cyst or ovarian parenchyma and puncture outside the abdominal skin. After cutting off the needles, both sides of the remaining suture were held together by a clamp, without knotting, so that the manipulator could "lift," "loosen," or "fix" the stitches to adjust the tension. The average time to create OSAS was 2.9 min. For the suspension and control groups, the average blood loss was 81.4 and 131.8 mL (p < .001), and the operative time was 42.0 and 61.3 min (p < .001), respectively. There were no significant differences in the incidence of complications (5.6% vs 9.1%; p = .365), but there were significant differences in conversions to standard non-single-site laparoscopy (5.6% vs 15.9%; p = .025) and laparotomy (1.1% vs 6.8%; p = .040). Logistic regression analysis revealed that the ratios of conversion to standard non-single-site laparoscopy (odds ratio [OR], 0.126; 95% confidence interval [CI], 0.311-0.508) and laparotomy (OR, 0.032; 95% CI, 0.002-0.479) were much lower in the suspension group; the risk of complications was comparable (OR, 0.346; 95% CI, 0.085-1.403). OSAS is an easy, safe, and feasible method that offers advantages during LESS. Although routine use of OSAS is not necessary, OSAS can be considered during LESS to facilitate the surgery. Copyright © 2015 AAGL. Published by Elsevier Inc. All

Suture slippage in knotless suture anchors resulting in subacromial-subdeltoid bursitis.

Science.gov (United States)

Hayeri, Mohammad Reza; Keefe, Daniel T; Chang, Eric Y

2016-05-01

Rotator cuff repair using a suture bridge and knotless suture anchors is a relatively new, but increasingly used technique. The suture bridge technique creates an anatomically similar and more secure rotator cuff repair compared with conventional arthroscopic techniques and the use of knotless anchors eliminates the challenges associated with knot tying during arthroscopic surgery. However, previous in vitro biomechanical tests have shown that the hold of the suture in a knotless suture anchor is far lower than the pullout strength of the anchor from bone. Up until now slippage has been a theoretical concern. We present a prospectively diagnosed case of in vivo suture loosening after rotator cuff repair using a knotless bridge technique resulting in subacromial-subdeltoid bursitis.

A single hidden layer feedforward network with only one neuron in the hidden layer can approximate any univariate function

OpenAIRE

Guliyev , Namig; Ismailov , Vugar

2016-01-01

The possibility of approximating a continuous function on a compact subset of the real line by a feedforward single hidden layer neural network with a sigmoidal activation function has been studied in many papers. Such networks can approximate an arbitrary continuous function provided that an unlimited number of neurons in a hidden layer is permitted. In this paper, we consider constructive approximation on any finite interval of $\\mathbb{R}$ by neural networks with only one neuron in the hid...

[Subluxation of scleral-fixated PC IOL caused by polypropylene suture degradation--case report].

Science.gov (United States)

Kanigowska, Krystyna; Grałek, Mirosława; Czarnowska, Elzbieta; Zajaczkowska, Agnieszka

2009-01-01

The purpose of the study is to evaluate factors related to late-onset of lens subluxation in transscleral sutured posterior chamber IOL. We report a child, which required surgical treatment for dislocation of a scleral-sutured PC IOL. 11 years earlier the secondary lens implantation with scleral fixation was performed in 4 years old boy. The first surgical procedure included an anterior victrectomy and suturing a single- piece PMMA IOL under the scleral flaps with a 10-0 polipropylene suture. The second--included explantation of the dislocated lens. Optic and scanning electron microscopy was used to analyze the surface of the explanted remnants of the breakage suture. Microscopic findings indicate that the late suture breakage and subluxation of suture-fixated PC IOL was due to the degradation of polypropylene suture.

Treatment of chronic deltoid ligament injury using suture anchors.

Science.gov (United States)

Wang, Xu; Ma, Xin; Zhang, Chao; Wang, Chen; Huang, Jia-zhang

2014-08-01

To explore the efficacy of overlapping suture-anchor fixation for treatment of chronic deltoid ligament injury. Seventeen patients (11 men, 6 women of mean age 32.1 years [range, 18-58 years]) who had undergone surgery for chronic deltoid ligament injury from January 2007 to December 2011 were retrospectively analyzed. Preoperatively, they had undergone bilateral weight-bearing posterior-anterior radiographs, (MRI) and ultrasound examinations of the ankle. Ankle arthroscopy was performed to confirm the diagnosis, followed by surgery to clear intra-articular proliferating synovial tissues and remove cartilage debris and scar tissue. The deep layer of the deltoid ligament was sutured onto the tip of the medial malleolus and its superficial layer sutured onto its periosteum and fixed with suture anchors. American Orthopedic Foot and Ankle Society (AOFAS) scoring system for the ankle-hindfoot was used to evaluate the ankles pre- and post-operatively. The 17 patients were followed up for 12-34 months (mean 20.1 months). The angle between the long axes of the talus and first metatarsal and the hindfoot angle measured in a hindfoot alignment view (as described by Saltzman) were reduced from 5.4° ± 1.8° and 8.2° ± 2.6° preoperatively to 4.0° ± 0.9° and 5.3° ± 1.3° postoperatively, respectively. The mean AOFAS ankle-hindfoot score was 76.8 ± 7.0 preoperatively and 94.1 ± 3.3 at the last follow-up visit. Ten patients were scored as excellent, six as good, and one as fair. Pain was relieved in all patients and no patients had recurrent deltoid ligament injury. Using suture anchors to treat chronic deltoid ligament injury has relatively satisfactory outcomes. © 2014 Chinese Orthopaedic Association and Wiley Publishing Asia Pty Ltd.

Comparison between suture anchor and transosseous suture for the modified-Broström procedure.

Science.gov (United States)

Cho, Byung-Ki; Kim, Yong-Min; Kim, Dong-Soo; Choi, Eui-Sung; Shon, Hyun-Chul; Park, Kyoung-Jin

2012-06-01

This prospective, randomized study was conducted to compare clinical outcomes of the modified Broström procedure using suture anchor or transosseous suture technique for chronic ankle instability. Forty patients were followed for more than 2 years after modified Broström procedure. Twenty procedures using a suture anchor and 20 procedures using a transosseous suture were performed by one surgeon. The clinical evaluation consisted of the Karlsson scale and the Sefton grading system. Talar tilt and anterior talar translation were measured on anterior and varus stress radiographs. The Karlsson scale had improved significantly to 90.8 points in the suture anchor group, and to 89.2 points in the transosseous suture group. According to Sefton grading system, 18 patients (90%) in suture anchor group and 17 patients (85%) in transosseous suture group achieved satisfactory results. The talar tilt angle and anterior talar translation improved significantly to 5.9 degrees and 4.2 mm in suture anchor group, and to 5.4 degrees and 4.1 mm in transosseous suture group, respectively. No significant differences existed in clinical and functional outcomes between the two techniques for ligament reattachment. Both modified Broström procedures using the suture anchor and transosseous suture seem to be effective treatment methods for chronic lateral ankle instability.

Functional and structural outcomes of single-row versus double-row versus combined double-row and suture-bridge repair for rotator cuff tears.

Science.gov (United States)

Mihata, Teruhisa; Watanabe, Chisato; Fukunishi, Kunimoto; Ohue, Mutsumi; Tsujimura, Tomoyuki; Fujiwara, Kenta; Kinoshita, Mitsuo

2011-10-01

Although previous biomechanical research has demonstrated the superiority of the suture-bridge rotator cuff repair over double-row repair from a mechanical point of view, no articles have described the structural and functional outcomes of this type of procedure. The structural and functional outcomes after arthroscopic rotator cuff repair may be different between the single-row, double-row, and combined double-row and suture-bridge (compression double-row) techniques. Cohort study; Level of evidence, 3. There were 206 shoulders in 201 patients with full-thickness rotator cuff tears that underwent arthroscopic rotator cuff repair. Eleven patients were lost to follow-up. Sixty-five shoulders were repaired using the single-row, 23 shoulders using the double-row, and 107 shoulders using the compression double-row techniques. Clinical outcomes were evaluated at an average of 38.5 months (range, 24-74 months) after rotator cuff repair. Postoperative cuff integrity was determined using Sugaya's classification of magnetic resonance imaging (MRI). The retear rates after arthroscopic rotator cuff repair were 10.8%, 26.1%, and 4.7%, respectively, for the single-row, double-row, and compression double-row techniques. In the subcategory of large and massive rotator cuff tears, the retear rate in the compression double-row group (3 of 40 shoulders, 7.5%) was significantly less than those in the single-row group (5 of 8 shoulders, 62.5%, P row group (5 of 12 shoulders, 41.7%, P row and suture-bridge techniques, which had the lowest rate of postoperative retear, is an effective option for arthroscopic repair of the rotator cuff tendons because the postoperative functional outcome in patients with a retear is inferior to that without retear.

Synthesis of Epitaxial Single-Layer MoS2 on Au(111).

Science.gov (United States)

Grønborg, Signe S; Ulstrup, Søren; Bianchi, Marco; Dendzik, Maciej; Sanders, Charlotte E; Lauritsen, Jeppe V; Hofmann, Philip; Miwa, Jill A

2015-09-08

We present a method for synthesizing large area epitaxial single-layer MoS2 on the Au(111) surface in ultrahigh vacuum. Using scanning tunneling microscopy and low energy electron diffraction, the evolution of the growth is followed from nanoscale single-layer MoS2 islands to a continuous MoS2 layer. An exceptionally good control over the MoS2 coverage is maintained using an approach based on cycles of Mo evaporation and sulfurization to first nucleate the MoS2 nanoislands and then gradually increase their size. During this growth process the native herringbone reconstruction of Au(111) is lifted as shown by low energy electron diffraction measurements. Within the MoS2 islands, we identify domains rotated by 60° that lead to atomically sharp line defects at domain boundaries. As the MoS2 coverage approaches the limit of a complete single layer, the formation of bilayer MoS2 islands is initiated. Angle-resolved photoemission spectroscopy measurements of both single and bilayer MoS2 samples show a dramatic change in their band structure around the center of the Brillouin zone. Brief exposure to air after removing the MoS2 layer from vacuum is not found to affect its quality.

Subluxation of suture-fixated posterior chamber intraocular lenses a clinicopathologic study.

Science.gov (United States)

Parekh, Parag; Green, W Richard; Stark, Walter J; Akpek, Esen Karamursel

2007-02-01

To report the occurrence of subluxation of suture-fixated posterior chamber (PC) intraocular lenses (IOL) and elucidate the mechanisms involved. Prospective clinicopathologic study. A single 10-0 Prolene suture explanted from a patient who experienced subluxation of his PC-IOL, 11.5 years after placement. Furthermore, multiple 10-0 Prolene sutures and PC-IOLs used for iris fixation were studied as controls. Scanning electron microscopy (SEM) was used to analyze the surface of the explanted suture. In addition, randomly selected 10-0 Prolene sutures cut with Vannas scissors and cut with the positioning holes of a randomly selected PC-IOL identical to that implanted in the patient's eye were examined as controls. Finally, the positioning holes of several randomly selected, iris-fixated PC-IOLs were studied using SEM with particular attention to surface quality and edge finish. Presence of any signs of suture degradation, the character of the cut edge of the suture, as well as the characteristics of the positioning holes of the PC-IOLs. Scanning electron microscopy of the explanted suture revealed sharply cut edges, without significant degradation of the suture, and no intact loop. Scanning electron microscopy of the control suture cut with a PC-IOL demonstrated a similarly cut edge. The positioning holes of the examined PC-IOLs had a sharp edge, and some also had an imperfect finish. We conclude that the surface properties of the positioning holes lead to cutting of the suture, and subsequent subluxation of the PC-IOL.

Single versus double-layer uterine closure at cesarean: impact on lower uterine segment thickness at next pregnancy.

Science.gov (United States)

Vachon-Marceau, Chantale; Demers, Suzanne; Bujold, Emmanuel; Roberge, Stephanie; Gauthier, Robert J; Pasquier, Jean-Charles; Girard, Mario; Chaillet, Nils; Boulvain, Michel; Jastrow, Nicole

2017-07-01

Uterine rupture is a potential life-threatening complication during a trial of labor after cesarean delivery. Single-layer closure of the uterus at cesarean delivery has been associated with an increased risk of uterine rupture compared with double-layer closure. Lower uterine segment thickness measurement by ultrasound has been used to evaluate the quality of the uterine scar after cesarean delivery and is associated with the risk of uterine rupture. To estimate the impact of previous uterine closure on lower uterine segment thickness. Women with a previous single low-transverse cesarean delivery were recruited at 34-38 weeks' gestation. Transabdominal and transvaginal ultrasound evaluation of the lower uterine segment thickness was performed by a sonographer blinded to clinical data. Previous operative reports were reviewed to obtain the type of previous uterine closure. Third-trimester lower uterine segment thickness at the next pregnancy was compared according to the number of layers sutured and according to the type of thread for uterine closure, using weighted mean differences and multivariate logistic regression analyses. Of 1613 women recruited, with operative reports available, 495 (31%) had a single-layer and 1118 (69%) had a double-layer closure. The mean third-trimester lower uterine segment thickness was 3.3 ± 1.3 mm and the proportion with lower uterine segment thickness cesarean delivery is associated with a thicker third-trimester lower uterine segment and a reduced risk of lower uterine segment thickness <2.0 mm in the next pregnancy. The type of thread for uterine closure has no significant impact on lower uterine segment thickness. Copyright © 2017 Elsevier Inc. All rights reserved.

Experience with single-layer rectal anastomosis.

OpenAIRE

Khubchandani, M; Upson, J

1981-01-01

Anastomotic dehiscence following resection of the large intestine is a serious complication. Satisfactory results of single-layer anastomosis depend upon meticulous technique and a scrupulously clean colon. Out of 65 single-layer anastomoses involving the rectum, significant leakage occurred in 4 patients. The results are reported in order to draw attention to the safety and efficacy of one-layer anastomosis.

Tutoring Trainees to Suture: An Alternative Method for Learning How to Suture and a Way to Compensate for a Lack of Suturing Cases.

Science.gov (United States)

Wongkietkachorn, Apinut; Rhunsiri, Peera; Boonyawong, Pangpoom; Lawanprasert, Attaporn; Tantiphlachiva, Kasaya

2016-01-01

Tutoring in suturing was developed to compensate for a shortage of suturing cases. The objective of this study was to compare ideal suturing score (ISS; 9 points), suturing time (min:sec), and suture placement error (mm) between medical students completing the suturing tutoring program and medical students attending ordinary medical school training program. Participants consisted of 2 groups of medical students who had never performed suturing. The study group had the role of suturing tutor to teach interested high school students. The control group consisted of volunteers from the ordinary medical school program. Skills measurement was performed by having students from both the groups perform 3 vertical mattress sutures on a model. The study group was tested at weeks 1, 9, and 10 to assess improvement. Both the groups were tested at week 10 to compare final learning outcome. There were 41 and 40 participants in the study group and the control group, respectively. ISS was significantly improved in the study group from week 1-week 10 (7.0 ± 1.3 vs. 8.2 ± 0.9, p = 0.01). At week 10, the study group had a higher mean ISS than the control group (8.2 ± 0.9 vs. 7.8 ± 1.1, p = 0.68). Mean suturing time and mean placement error were also lower in the study group at the end of suturing training (5:1 ± 1:0 vs. 5:2 ± 1:2, p = 0.13; 7.4 ± 7.4 vs. 8.0 ± 10.8, p = 0.44). Tutoring trainees to suture can improve a student's ability to learn how to suture. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Selective laser vaporization of polypropylene sutures and mesh

Science.gov (United States)

Burks, David; Rosenbury, Sarah B.; Kennelly, Michael J.; Fried, Nathaniel M.

2012-02-01

Complications from polypropylene mesh after surgery for female stress urinary incontinence (SUI) may require tedious surgical revision and removal of mesh materials with risk of damage to healthy adjacent tissue. This study explores selective laser vaporization of polypropylene suture/mesh materials commonly used in SUI. A compact, 7 Watt, 647-nm, red diode laser was operated with a radiant exposure of 81 J/cm2, pulse duration of 100 ms, and 1.0-mm-diameter laser spot. The 647-nm wavelength was selected because its absorption by water, hemoglobin, and other major tissue chromophores is low, while polypropylene absorption is high. Laser vaporization of ~200-μm-diameter polypropylene suture/mesh strands, in contact with fresh urinary tissue samples, ex vivo, was performed. Non-contact temperature mapping of the suture/mesh samples with a thermal camera was also conducted. Photoselective vaporization of polypropylene suture and mesh using a single laser pulse was achieved with peak temperatures of 180 and 232 °C, respectively. In control (safety) studies, direct laser irradiation of tissue alone resulted in only a 1 °C temperature increase. Selective laser vaporization of polypropylene suture/mesh materials is feasible without significant thermal damage to tissue. This technique may be useful for SUI procedures requiring surgical revision.

Evaluation of a novel suture material for closure of intestinal anastomoses in canine cadavers.

Science.gov (United States)

Hansen, Lane A; Monnet, Eric L

2012-11-01

To compare leakage and maximum intraluminal pressures for a novel suture material with pressures for comparable suture material when used in closure of intestinal anastomoses in canine cadavers. Healthy intestines from cadavers of dogs euthanized for reasons unrelated to the study. 18 anastomoses were performed on intestinal sections within 72 hours after dogs were euthanized and intestinal samples collected. Anastomoses were performed with a simple continuous suture pattern. Leakage and maximum intraluminal pressures were measured and recorded for 6 control segments and 18 anastomosed sections. A barbed glycomer 631 suture (size 4-0 United States Pharmacopeia [USP]) was compared with glycomer 631 sutures (sizes 3-0 and 4-0 USP). Results for leakage and maximum intraluminal pressures were compared via an ANOVA. The barbed glycomer 631 suture material leaked at a significantly higher pressure than did the comparable glycomer 631 suture materials. Maximum intraluminal pressures were not significantly different among the suture materials. Barbed glycomer 631 4-0 USP suture material was as effective as glycomer 631 suture materials and may be a safe alternative for use in closure of enterectomies in dogs.

Automatic settlement analysis of single-layer armour layers

NARCIS (Netherlands)

Hofland, B.; van gent, Marcel

2016-01-01

A method to quantify, analyse, and present the settlement of single-layer concrete armour layers of coastal structures is presented. The use of the image processing technique for settlement analysis is discussed based on various modelling
studies performed over the years. The accuracy of the

The Efficacy of Polydioxanone Monofilament Absorbable Suture for Tracheal Anastomosis

OpenAIRE

Kawahara, Katsunobu; Yamasaki, Naoya; Yamamoto, Satoshi; Nagayasu, Takeshi; Kusano, Hiroyuki; Akamine, Shinji; Takahashi, Takao; Tomita, Masao

1994-01-01

To evaluate the efficacy of polydioxanon absorbable suture for tracheal anastomoses, we performed an experimental study using dose. Eight adult mongrel dogs underwent sleeve resection of the mediastinal trachea. A length of ten to twelve cartilage rings was resected. An end-to-end anastomosis was performed using either interrupted or continuous running 4-0 polydioxanone (PDS) suture. There was no detectable difference bronchoscopically, microangiografically, or histologically, in tracheal ana...

Functional and structural comparisons of the arthroscopic knotless double-row suture bridge and single-row repair for anterosuperior rotator cuff tears.

Science.gov (United States)

Ide, Junji; Karasugi, Tatsuki; Okamoto, Nobukazu; Taniwaki, Takuya; Oka, Kiyoshi; Mizuta, Hiroshi

2015-10-01

We compared the outcomes of knotless double-row suture bridge and single-row repairs in patients undergoing arthroscopic repair for anterosuperior rotator cuff tears. We included 61 full-thickness anterosuperior rotator cuff tears treated by arthroscopic repair, namely, single-row repair (group 1: 25 shoulders; mean patient age, 64 years) and the knotless double-row suture bridge repair (group 2: 36 shoulders; mean patient age, 62 years). Preoperative and postoperative magnetic resonance imaging was performed for all shoulders. Clinical outcomes were evaluated for mean follow-up periods of 81 months (range, 72-96 months) in group 1 and 34 months (range, 24-42 months) in group 2, using the University of California, Los Angeles and Japanese Orthopaedic Association assessments. At the final follow-up, both groups showed improvement in the average University of California, Los Angeles and Japanese Orthopaedic Association scores and range of motion, although no intergroup differences were observed. Both groups showed improved abduction strength, and the average score was higher in group 2 (P = .0112). The lift-off and belly-press test results were improved in both groups. Postoperatively, the incidence of positive lift-off tests tended to be lower (P = .075) and that of positive belly-press tests was lower in group 2, P = .049). The repair failure rate tended to be lower in group 2 (14% [5 of 36]) than in group 1 (32% [8 of 25]; P = .0839). Arthroscopic knotless double-row suture bridge repair of anterosuperior rotator cuff tears yielded functional outcomes equivalent to those of single-row repair and may be useful for improving subscapularis function, abduction strength, and tendon healing. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Genipin crosslinker releasing sutures for improving the mechanical/repair strength of damaged connective tissue.

Science.gov (United States)

Sundararaj, Sharath; Slusarewicz, Paul; Brown, Matt; Hedman, Thomas

2017-11-01

The most common mode of surgical repair of ruptured tendons and ligaments involves the use of sutures for reattachment. However, there is a high incidence of rerupture and repair failure due to pulling out of the suture material from the damaged connective tissue. The main goal of this research was to achieve a localized delivery of crosslinking agent genipin (GP) from rapid-release biodegradable coatings on sutures, for strengthening the repair of ruptured connective tissue. Our hypothesis is that GP released from the suture coating will lead to exogenous crosslinking of native connective tissue resulting in beneficial effects on clinically relevant mechanical parameters such as tear resistance, tissue strength, and energy required to rupture the tissue (toughness). Sutures were successfully coated with a biodegradable polymer layer loaded with the crosslinking agent genipin, without compromising the mechanical properties of the suture. The rapid-release of genipin was achieved under both in vitro and ex vivo conditions. Exogenous crosslinking using these genipin releasing sutures was demonstrated using equine tendons. The tendons treated with genipin releasing sutures showed significant improvement in failure load, energy required for pull-out failure, and stiffness. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2199-2205, 2017. © 2016 Wiley Periodicals, Inc.

High-Tensile Strength Tape Versus High-Tensile Strength Suture: A Biomechanical Study.

Science.gov (United States)

Gnandt, Ryan J; Smith, Jennifer L; Nguyen-Ta, Kim; McDonald, Lucas; LeClere, Lance E

2016-02-01

To determine which suture design, high-tensile strength tape or high-tensile strength suture, performed better at securing human tissue across 4 selected suture techniques commonly used in tendinous repair, by comparing the total load at failure measured during a fixed-rate longitudinal single load to failure using a biomechanical testing machine. Matched sets of tendon specimens with bony attachments were dissected from 15 human cadaveric lower extremities in a manner allowing for direct comparison testing. With the use of selected techniques (simple Mason-Allen in the patellar tendon specimens, whip stitch in the quadriceps tendon specimens, and Krackow stitch in the Achilles tendon specimens), 1 sample of each set was sutured with a 2-mm braided, nonabsorbable, high-tensile strength tape and the other with a No. 2 braided, nonabsorbable, high-tensile strength suture. A total of 120 specimens were tested. Each model was loaded to failure at a fixed longitudinal traction rate of 100 mm/min. The maximum load and failure method were recorded. In the whip stitch and the Krackow-stitch models, the high-tensile strength tape had a significantly greater mean load at failure with a difference of 181 N (P = .001) and 94 N (P = .015) respectively. No significant difference was found in the Mason-Allen and simple stitch models. Pull-through remained the most common method of failure at an overall rate of 56.7% (suture = 55%; tape = 58.3%). In biomechanical testing during a single load to failure, high-tensile strength tape performs more favorably than high-tensile strength suture, with a greater mean load to failure, in both the whip- and Krackow-stitch models. Although suture pull-through remains the most common method of failure, high-tensile strength tape requires a significantly greater load to pull-through in a whip-stitch and Krakow-stitch model. The biomechanical data obtained in the current study indicates that high-tensile strength tape may provide better repair

Towards a viscoelastic model for the unfused midpalatal suture: development and validation using the midsagittal suture in New Zealand white rabbits.

Science.gov (United States)

Romanyk, D L; Liu, S S; Lipsett, M G; Toogood, R W; Lagravère, M O; Major, P W; Carey, J P

2013-06-21

Maxillary expansion treatment is a commonly used procedure by orthodontists to widen a patient's upper jaw. As this is typically performed in adolescent patients, the midpalatal suture, connective tissue adjoining the two maxilla halves, remains unfused. Studies that have investigated patient response to expansion treatment, generally through finite element analysis, have considered this suture to behave in a linear elastic manner or it was left vacant. The purpose of the study presented here was to develop a model that could represent the midpalatal suture's viscoelastic behavior. Quasilinear viscoelastic, modified superposition, Schapery's, and Burgers modeling approaches were all considered. Raw data from a previously published study using New Zealand White Rabbits was utilized for model parameter estimation and validation. In this study, Sentalloy(®) coil springs at load levels of 0.49N (50g), 0.98N (100g), and 1.96N (200g) were used to widen the midsagittal suture of live rabbits over a period of 6 weeks. Evaluation was based on a models ability to represent experimental data well over all three load sets. Ideally, a single set of model constants could be used to represent data over all loads tested. Upon completion of the analysis it was found that the modified superposition method was able to replicate experimental data within one standard deviation of the means using a single set of constants for all loads. Future work should focus on model improvement as well as prediction of treatment outcomes. Copyright © 2013 Elsevier Ltd. All rights reserved.

A biomechanical comparison of tendon-bone interface motion and cyclic loading between single-row, triple-loaded cuff repairs and double-row, suture-tape cuff repairs using biocomposite anchors.

Science.gov (United States)

Barber, F Alan; Drew, Otis R

2012-09-01

To compare tendon-bone interface motion and cyclic loading in a single-row, triple-loaded anchor repair with a suture-tape, rip-stop, double-row rotator cuff repair. Using 18 human shoulders from 9 matched cadaveric pairs, we created 2 groups of rotator cuff repairs. Group 1 was a double-row, rip-stop, suture-tape construct. Group 2 was a single-row, triple-loaded construct. Before mechanical testing, the supraspinatus footprint was measured with calipers. A superiorly positioned digital camera optically measured the tendon footprint motion during 60° of humeral internal and external rotation. Specimens were secured at a fixed angle not exceeding 45° in reference to the load. After preloading, each sample was cycled between 10 N and 100 N for 200 cycles at 1 Hz, followed by destructive testing at 33 mm/s. A digital camera with tracking software measured the repair displacement at 100 and 200 cycles. Ultimate load and failure mode for each sample were recorded. The exposed anterior footprint border (6.5% ± 6%) and posterior footprint border (0.9% ± 1.7%) in group 1 were statistically less than the exposed anterior footprint border (30.3% ± 17%) and posterior footprint border (29.8% ± 14%) in group 2 (P = .003 and P row rotator cuff repair had greater footprint coverage, less rotational footprint displacement, and a greater mean ultimate failure load than the triple-loaded, single-row repair on mechanical testing. No double-row or single-row constructs showed 5 mm of displacement after the first 100 cycles. The most common failure mode for both constructs was suture tearing through the tendon. Differences in cuff fixation influence rotational tendon movement and may influence postoperative healing. Stronger repair constructs still fail at the suture-tendon interface. Copyright © 2012 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Language, learning, and memory in children with and without single-suture craniosynostosis.

Science.gov (United States)

Kapp-Simon, Kathleen A; Wallace, Erin; Collett, Brent R; Cradock, Mary Michaeleen; Crerand, Canice E; Speltz, Matthew L

2016-05-01

OBJECTIVE The language and memory functions of children with and without single-suture craniosynostosis (SSC) were compared at school age (mean 7.45 years, standard deviation [SD] 0.54 years). The children in this cohort were originally recruited in infancy and prior to cranial surgery for those with SSC. METHODS Individual evaluations of 179 school-aged children with SSC and 183 controls were conducted (70% of the original cohort) using standardized measures of language, learning, and memory. Parents participated in an interview about specialized education interventions and school progress. Parents and teachers completed questionnaires about language development. RESULTS Children with SSC (cases) obtained lower scores than controls on all measures. The adjusted differences in language, learning, and memory scores were modest, with SD ranging from 0.0 to -0.4 (p values ranged from 0.001 to 0.99). Censored normal regression was used to account for intervention services received prior to the school-age evaluation; this increased case-control differences (SD range 0.1 to -0.5, p value range 0.001 to 0.50). Mean scores for cases in each SSC diagnostic group were lower than those for controls, with the greatest differences observed among children with unilateral coronal craniosynostosis. CONCLUSIONS Children with SSC continue to show poorer performance than controls on language, learning, and memory tasks at early elementary school age, even when controlling for known confounders, although mean differences are small. Multidisciplinary care, including direct psychological assessment, for children with SSC should extend through school age with a specific focus on language and conceptual learning, as these are areas of potential risk. Future research is needed to investigate language, memory, and learning for this population during the middle to high school years.

Effects of suture position on left ventricular fluid mechanics under mitral valve edge-to-edge repair.

Science.gov (United States)

Du, Dongxing; Jiang, Song; Wang, Ze; Hu, Yingying; He, Zhaoming

2014-01-01

Mitral valve (MV) edge-to-edge repair (ETER) is a surgical procedure for the correction of mitral valve regurgitation by suturing the free edge of the leaflets. The leaflets are often sutured at three different positions: central, lateral and commissural portions. To study the effects of position of suture on left ventricular (LV) fluid mechanics under mitral valve ETER, a parametric model of MV-LV system during diastole was developed. The distribution and development of vortex and atrio-ventricular pressure under different suture position were investigated. Results show that the MV sutured at central and lateral in ETER creates two vortex rings around two jets, compared with single vortex ring around one jet of the MV sutured at commissure. Smaller total orifices lead to a higher pressure difference across the atrio-ventricular leaflets in diastole. The central suture generates smaller wall shear stresses than the lateral suture, while the commissural suture generated the minimum wall shear stresses in ETER.

Single port Billroth I gastrectomy

Directory of Open Access Journals (Sweden)

Jeremy R Huddy

2013-01-01

Full Text Available Introduction: Experience has allowed increasingly complex procedures to be undertaken by single port surgery. We describe a technique for single port Billroth I gastrectomy with a hand-sewn intracorporeal anastomosis in the resection of a benign tumour diagnosed incidentally on a background of cholelithiasis. Materials and Methods: Single port Billroth I gastrectomy and cholecystectomy was performed using a transumbilical quadport. Flexible tipped camera and straight conventional instruments were used throughout the procedure. The stomach was mobilised including a limited lymph node dissection and resection margins in the proximal antrum and duodenum were divided with a flexible tipped laparoscopic stapler. The lesser curve was reconstructed and an intracorporal hand sewn two layer end-to-end anastomosis was performed using unidirectional barbed sutures. Intraoperative endoscopy confirmed the anastomosis to be patent without leak. Results: Enteral feed was started on the day of surgery, increasing to a full diet by day 6. Analgesic requirements were a patient-controlled analgesia morphine pump for 4 postoperative days and paracetamol for 6 days. There were no postoperative complications and the patient was discharged on the eighth day. Histology confirmed gastric submucosal lipoma. Discussion: As technology improves more complex procedures are possible by single port laparoscopic surgery. In this case, flexible tipped cameras and unidirectional barbed sutures have facilitated an intracorporal hand-sewn two layer end-to-end anastomosis. Experience will allow such techniques to become mainstream.

In vitro biomechanical comparison of three different types of single- and double-row arthroscopic rotator cuff repairs: analysis of continuous bone-tendon contact pressure and surface during different simulated joint positions.

Science.gov (United States)

Grimberg, Jean; Diop, Amadou; Kalra, Kunal; Charousset, Christophe; Duranthon, Louis-Denis; Maurel, Nathalie

2010-03-01

We assessed bone-tendon contact surface and pressure with a continuous and reversible measurement system comparing 3 different double- and single-row techniques of cuff repair with simulation of different joint positions. We reproduced a medium supraspinatus tear in 24 human cadaveric shoulders. For the 12 right shoulders, single-row suture (SRS) and then double-row bridge suture (DRBS) were used. For the 12 left shoulders, DRBS and then double-row cross suture (DRCS) were used. Measurements were performed before, during, and after knot tying and then with different joint positions. There was a significant increase in contact surface with the DRBS technique compared with the SRS technique and with the DRCS technique compared with the SRS or DRBS technique. There was a significant increase in contact pressure with the DRBS technique and DRCS technique compared with the SRS technique but no difference between the DRBS technique and DRCS technique. The DRCS technique seems to be superior to the DRBS and SRS techniques in terms of bone-tendon contact surface and pressure. Copyright 2010 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Optical properties of single-layer, double-layer, and bulk MoS2

Energy Technology Data Exchange (ETDEWEB)

Molina-Sanchez, Alejandro; Wirtz, Ludger [University of Luxembourg (Luxembourg); Hummer, Kerstin [University of Vienna, Vienna (Austria)

2013-07-01

The rise of graphene has brought attention also to other layered materials that can complement graphene or that can be an alternative in applications as transistors. Single-layer MoS{sub 2} has shown interesting electronic and optical properties such as as high electron mobility at room temperature and an optical bandgap of 1.8 eV. This makes the material suitable for transistors or optoelectronic devices. We present a theoretical study of the optical absorption and photoluminescence spectra of single-layer, double-layer and bulk MoS{sub 2}. The excitonic states have been calculated in the framework of the Bethe-Salpeter equation, taking into account the electron-hole interaction via the screened Coulomb potential. In addition to the step-function like behaviour that is typical for the joint-density of states of 2D materials with parabolic band dispersion, we find a bound excitonic peak that is dominating the luminescence spectra. The peak is split due to spin-orbit coupling for the single-layer and split due to layer-layer interaction for few-layer and bulk MoS{sub 2}. We discuss the changes of the optical bandgap and of the exciton binding energy with the number of layers, comparing our results with the reported experimental data.

Modified method for bronchial suture by Ramirez Gama compared to separate stitches suture: experimental study

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Vitor Mayer de Moura

Full Text Available OBJECTIVE: To experimentally compare two classic techniques described for manual suture of the bronchial stump. METHODS: We used organs of pigs, with isolated trachea and lungs, preserved by refrigeration. We dissected 30 bronchi, which were divided into three groups of ten bronchi each, of 3mm, 5mm, and 7mm, respectively. In each, we performed the suture with simple, separated, extramucosal stitches in five other bronchi, and the technique proposed by Ramirez and modified by Santos et al in the other five. Once the sutures were finished, the anastomoses were tested using compressed air ventilation, applying an endotracheal pressure of 20mmHg. RESULTS: the Ramirez Gama suture was more effective in the bronchi of 3, 5 and 7 mm, and there was no air leak even after subjecting them to a tracheal pressure of 20mmHg. The simple interrupted sutures were less effective, with extravasation in six of the 15 tested bronchi, especially in the angles of the sutures. These figures were not significant (p = 0.08. CONCLUSION: manual sutures of the bronchial stumps were more effective when the modified Ramirez Gama suture was used in the caliber bronchi arms when tested with increased endotracheal pressure.

A multicenter randomized controlled trial comparing absorbable barbed sutures versus conventional absorbable sutures for dermal closure in open surgical procedures.

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Rubin, J Peter; Hunstad, Joseph P; Polynice, Alain; Gusenoff, Jeffrey A; Schoeller, Thomas; Dunn, Raymond; Walgenbach, Klaus J; Hansen, Juliana E

2014-02-01

Barbed sutures were developed to reduce operative time and improve security of wound closure. The authors compare absorbable barbed sutures (V-Loc, Covidien, Mansfield, Massachusetts) with conventional (smooth) absorbable sutures for soft tissue approximation. A prospective multicenter randomized study comparing barbed sutures with smooth sutures was undertaken between August 13, 2009, and January 31, 2010, in 241 patients undergoing abdominoplasty, mastopexy, and reduction mammaplasty. Each patient received barbed sutures on 1 side of the body, with deep dermal sutures eliminated or reduced. Smooth sutures with deep dermal and subcuticular closure were used on the other side as a control. The primary endpoint was dermal closure time. Safety was assessed through adverse event reporting through a 12-week follow-up. A total of 229 patients were ultimately treated (115 with slow-absorbing polymer and 114 with rapid-absorbing polymer). Mean dermal closure time was significantly quicker with the barbed suture compared with the smooth suture (12.0 vs 19.2 minutes; P<.001), primarily due to the need for fewer deep dermal sutures. The rapid-absorbing barbed suture showed a complication profile equivalent to the smooth suture, while the slow-absorbing barbed suture had a higher incidence of minor suture extrusion. Barbed sutures enabled faster dermal closure quicker than smooth sutures, with a comparable complication profile. 1.

Experimental evaluation of horse hair as a nonabsorbable monofilament suture

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Swati R Yedke

2013-01-01

Full Text Available Background: Success of surgery depends on wound closure and healing. Ancients had coated many suture materials from plant and animal origin. As the quest for natural nonabsorbable, monofilament surgical suture continues, horsehair has been taken for study, which is mentioned in ancient literature. Objectives: Aim of the study was to evaluate detail mechanical and biophysical properties of horsehair. Materials and Methods: Physical properties, that are diameter, straight pull and knot pull tensile strength, bioburden, sterility tests were performed. Visual and histological wound healing parameters were studied in experimental Wistar rat incision wound model. Two experimental wounds about 5 cm long were created on each side of dorsal midline. Each animal received two sutures-Horsehair 4-0 and Ethilon 4-0. The sutured areas were grossly examined on 3 rd and 7 th days for visual observations like congestion, edema, infection, wound disruption, and impression of suture material on healed wound and then subjected for histological study. Results: Revealed that horsehair has got diameter of 0.19 mm which complies with the 4-0 size USP standard. Straight pull tensile strength was found 0.5851 ± 0.122 kg and knot pull tensile strength was 0.3998 ± 0.078 kg, which complies with the standards of United State Pharmacopia for class II nonabsorbable suture materials. In vivo study revealed that there was no evidence of edema, congestion, and discharge in both the groups. Wounds healed with minimum impressions of suture material with minimum scar mark. Mean histological scoring shows very mild tissue reaction. Conclusion: Horsehair has got properties of standard suture material except low tensile strength and hence can be used in reconstructive, plastic surgeries, and ophthalmic surgeries.

Breakwater stability with damaged single layer armour units

OpenAIRE

De Rover, R.; Verhagen, H.J.; Van den Berge, A.; Reedijk, B.

2008-01-01

The effect of single layer interlocking armour unit breakage on the hydraulic armour layer stability and potential damage progression is addressed in this paper. A 2-dimensional scale model of a rubble mound breakwater with an armour layer consisting of Xbloc armour units was tested. The residual armour layer stability with broken units was determined. The armour unit displacement and damage progression was assessed. According to the test series breakage of the single layer armour units has a...

Comparison of barbed unidirectional suture with figure-of-eight standard sutures in vaginal cuff closure in total laparoscopic hysterectomy.

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Karacan, Tolga; Ozyurek, Eser; Usta, Taner; Odacilar, Eylem; Hanli, Ulviye; Kovalak, Ebru; Dayan, Huseyin

2018-03-24

The aim of the study was to compare postoperative vaginal cuff complications due to the use of barbed sutures (V-Loc™ 180 unidirectional suture; Covidien, Mansfield, MA) and standard braided sutures (Vicryl ® ; Ethicon Inc., Somerville, MA) during vaginal cuff closure of patients undergoing a total laparoscopic hysterectomy (TLH) due to benign diseases. Eighty-nine patients were in the standard suture group and 208 patients were included in the barbed suture group. Vaginal cuff dehiscence was identified in only three (3.3%) patients within the standard suture group and none in the barbed suture group. Five (5.6%) patients in the standard suture group and two (0.9%) patients in the barbed suture group developed postoperative cuff infection/cellulitis. Duration of the surgery was significantly shorter in the barbed suture group than in the standard suture group (p barbed suture, which is used during TLH for vaginal cuff closure, is an applicable, safe and tolerable alternative to a standard suture. IMPACT STATEMENT What is already known on this subject: Barbed sutures are a relatively new type of suture that include sharp barbs inserted on monofilament material in various configurations, and are used for approximating tissues without any need for surgical knotting. They have increasingly been used in obstetrics and gynaecology in recent years, particularly in total laparoscopic hysterectomy and laparoscopic myomectomy. At present, there are a limited number of studies of V-Loc™ suture in the literature. What the results of this study add: We demonstrated that barbed sutures used for enabling vaginal cuff integrity did not cause major morbidity and mortality for the patient. We suggest that V-Loc™ 180 barbed sutures offer a practical, safe and tolerable alternative for surgeons because they are easy to use, do not cause a significant increase in vaginal cuff complications, and shorten the operating time. Our study with V-Loc™ 180 unidirectional barbed

A randomized clinical trial of knotless barbed suture vs conventional suture for closure of the uterine incision at cesarean delivery.

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Peleg, David; Ahmad, Ronan Said; Warsof, Steven L; Marcus-Braun, Naama; Sciaky-Tamir, Yael; Ben Shachar, Inbar

2018-03-01

Knotless barbed sutures are monofilament sutures with barbs cut into them. These sutures self-anchor, maintaining tissue approximation without the need for surgical knots. The hypothesis of this study was that knotless barbed suture could be used on the myometrium to close the hysterotomy at cesarean delivery. The objective was to compare uterine closure time, need for additional sutures, and blood loss between this and a conventional suture. This was a prospective, unblinded, randomized controlled trial conducted at the Ziv Medical Center, Zefat, Israel. The primary outcome was the length of time needed to close the uterine incision, which was measured from the start of the first suture on the uterus until obtaining uterine hemostasis. To minimize provider bias, women were randomized by sealed envelopes that were opened in the operating room just prior to uterine closure with either a bidirectional knotless barbed suture or conventional suture. Secondary outcomes included the number of additional hemostatic sutures needed and blood loss during incision closure. Patients were enrolled from August 2016 until March 2017. One hundred two women were randomized. Fifty-one had uterine closure with knotless barbed suture and 51 with conventional suture. The groups were similar for demographics as well as number of previous cesarean deliveries. Uterine closure time using the knotless barbed suture was significantly shorter than the conventional suture by a mean of 1 minute 43 seconds (P barbed sutures were associated with a lower need for hemostatic sutures (median 0 vs 1, P barbed suture is a reasonable alternative to conventional sutures because it reduced the closure time of the uterine incision. There was also less need for additional hemostatic sutures and slightly reduced estimated blood loss. Copyright © 2018 Elsevier Inc. All rights reserved.

Synthesis of single-crystalline Al layers in sapphire

International Nuclear Information System (INIS)

Schlosser, W.; Lindner, J.K.N.; Zeitler, M.; Stritzker, B.

1999-01-01

Single-crystalline, buried aluminium layers were synthesized by 180 keV high-dose Al + ion implantation into sapphire at 500 deg. C. The approximately 70 nm thick Al layers exhibit in XTEM investigations locally abrupt interfaces to the single-crystalline Al 2 O 3 top layer and bulk, while thickness and depth position are subjected to variations. The layers grow by a ripening process of oriented Al precipitates, which at low doses exist at two different orientations. With increasing dose, precipitates with one out of the two orientations are observed to exist preferentially, finally leading to the formation of a single-crystalline layer. Al outdiffusion to the surface and the formation of spherical Al clusters at the surface are found to be competing processes to buried layer formation. The formation of Al layers is described by Rutherford Backscattering Spectroscopy (RBS), Cross-section transmission electron microscopy (XTEM) and Scanning electron microscopy (SEM) studies as a function of dose, temperature and substrate orientation

[Laparoscopic suture or open suture in perforated duodenal ulcer].

Science.gov (United States)

Nicolau, A E; Ionescu, G; Iordache, F; Mehic, R; Spătaru, A

2002-01-01

Between Nov. 1994-Jan. 2001 we performed laparoscopic suture with omentoplasty of perforated duodenal ulcer (PDU) in 51 patients out of 56 it was intended (this constituted the laparoscopic group--LG). The selection criteria were young patients, age < 40 years, no associated diseases, onset of the operation under 12 hours from the occurrence of the perforation, absence of clear ulcer history. In the same period, we performed an open suture based on the same criteria in 105 patients (open group--OP). The results showed a difference between needed analgesia (2.8 days for LG vs. 5.2 days for OG) and a hospital stay of 6.1 days in LG vs. 7.7 days in OG. The incidence of postoperative complications was 5.88% in the LG and 7.61% in the OG with 1.96% and respective 1.90% reoperation rate. In conclusion laparoscopic suture of PDU with associated postoperative modern therapy of ulcer disease could be the treatment of choice in young patients.

11-GHz waveguide Nd:YAG laser CW mode-locked with single-layer graphene.

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Okhrimchuk, Andrey G; Obraztsov, Petr A

2015-06-08

We report stable, passive, continuous-wave (CW) mode-locking of a compact diode-pumped waveguide Nd:YAG laser with a single-layer graphene saturable absorber. The depressed cladding waveguide in the Nd:YAG crystal is fabricated with an ultrafast laser inscription method. The saturable absorber is formed by direct deposition of CVD single-layer graphene on the output coupler. The few millimeter-long cavity provides generation of 16-ps pulses with repetition rates in the GHz range (up to 11.3 GHz) and 12 mW average power. Stable CW mode-locking operation is achieved by controlling the group delay dispersion in the laser cavity with a Gires-Tournois interferometer.

Raman study of supported molybdenum disulfide single layers

Science.gov (United States)

Durrer, William; Manciu, Felicia; Afanasiev, Pavel; Berhault, Gilles; Chianelli, Russell

2008-10-01

Owing to the increasing demand for clean transportation fuels, highly dispersed single layer transition metal sulfides such as MoS2-based catalysts play an important role in catalytic processes for upgrading and removing sulfur from heavy petroleum feed. In its crystalline bulk form, MoS2 is chemically rather inactive due to a strong tendency to form highly stacked layers, but, when dispersed as single-layer nanoclusters on a support, the MoS2 becomes catalytically active in the hydrogenolysis of sulphur and nitrogen from organic compounds (hydrotreating catalysis). In the present studies alumina-supported MoS2 samples were analyzed by confocal Raman spectroscopy. Evidence of peaks at 152 cm-1, 234 cm-1, and 336 cm-1, normally not seen in the Raman spectrum of the standard bulk crystal, confirms the formation of single layers of MoS2. Furthermore, the presence of the 383 cm-1 Raman line suggests the trigonal prismatic coordination of the formed MoS2 single layers. Depending on the sample preparation method, a restacking of MoS2 layers is also observed, mainly for ex-thiomolybdate samples sulfided at 550 C.

MonoMax Suture: A New Long-Term Absorbable Monofilament Suture Made from Poly-4-Hydroxybutyrate

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Erich K. Odermatt

2012-01-01

Full Text Available A long-term absorbable monofilament suture was developed using poly-4-hydroxybutyrate (P4HB made from a biosynthetically produced homopolymer of the natural metabolite 4-hydroxybutyrate. The suture, called MonoMax, has prolonged strength retention. At 12 weeks, a size 3-0 MonoMax suture retains approximately 50% of its initial tensile strength in vivo and is substantially degraded in one year with minimal tissue reaction. In contrast, PDS II monofilament suture (Ethicon, Inc., Somerville, NJ has no residual strength in vivo after 12 weeks. In vivo, the MonoMax suture is hydrolyzed primarily by bulk hydrolysis, and is then degraded via the Krebs cycle. MonoMax is substantially more compliant than other monofilament sutures, and incorporates an element of elasticity. Its tensile modulus of 0.48 GPa is approximately one-third of the value of the PDS II fiber providing an exceptionally flexible and pliable fiber with excellent knot strength and security. These features are further enhanced by the fiber's elasticity, which also improves knot security and may help prevent wound dehiscence. Because of its performance advantages, this suture may find clinical utility in applications where prolonged strength retention, and greater flexibility are required, particularly in procedures like abdominal wall closure where wound dehiscence is still a significant post-surgical complication.

Epitaxial TiN(001) wetting layer for growth of thin single-crystal Cu(001)

Energy Technology Data Exchange (ETDEWEB)

Chawla, J. S.; Zhang, X. Y.; Gall, D. [Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

2011-08-15

Single-crystal Cu(001) layers, 4-1400 nm thick, were deposited on MgO(001) with and without a 2.5-nm-thick TiN(001) buffer layer. X-ray diffraction and reflection indicate that the TiN(001) surface suppresses Cu-dewetting, yielding a 4 x lower defect density and a 9 x smaller surface roughness than if grown on MgO(001) at 25 deg. C. In situ and low temperature electron transport measurements indicate that ultra-thin (4 nm) Cu(001) remains continuous and exhibits partial specular scattering at the Cu-vacuum boundary with a Fuchs-Sondheimer specularity parameter p = 0.6 {+-} 0.2, suggesting that the use of epitaxial wetting layers is a promising approach to create low-resistivity single-crystal Cu nanoelectronic interconnects.

Single suture iris-to-capsulorhexis fixation for in-the-bag intraocular lens subluxation.

Science.gov (United States)

Siegel, Michael J; Condon, Garry P

2015-11-01

We present a simplified modification to a technique for early or mild in-the-bag subluxation that avoids conjunctival and scleral incisions and minimizes intraocular manipulation. While the capsulorhexis edge is grasped with an intraocular forceps to stabilize the IOL-capsular bag complex, a 10-0 polypropylene suture on a long curved needle is used to secure the fibrotic superior capsulorhexis edge to the midperipheral iris at 12 o'clock using a combination of a modified McCannel suture and a Siepser sliding knot. Dr. Condon receives speaker and consultant fees from Alcon Surgical, Inc., Allergan, Inc., and Microsurgical Technology. Although the Microsurgical Technology Condon snare instrument is named after him, Dr. Condon reports no patents, fees, or payments related to it. Dr. Siegel has no financial or proprietary interest in any material or method mentioned. Copyright © 2015. Published by Elsevier Inc.

Absorbable Suture as an Apical Matrix in Single Visit Apexification with Mineral Trioxide Aggregate

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Ayush Goyal

2016-01-01

Full Text Available Several procedures have been recommended to induce the root end barrier formation in teeth with open apices. Conventional treatment for such cases will require many appointments with an average duration of 12.9 months. During this period, the root canal is susceptible to reinfection from around the provisional restoration, which may promote apical periodontitis and arrest of apical repair. Mineral trioxide aggregate (MTA has been successfully used for one visit apexification wherein the root canal can be obturated within 24 hours after placement of MTA. Using a matrix prior to the placement of MTA avoids its extrusion, reduces leakage in the sealing material, and allows favorable response of the periapical tissues. This report presents a case of apexification where an absorbable suture was used as an apical matrix. Use of an absorbable suture circumvents all the problems associated with other conventional materials. Conclusion. Placement of the matrix made from the suture material is predictable and is easily positioned at the apex and the length can be adjusted as required. 10-month follow-up of the case shows resorbed matrix and bone healing in the periapical region. The patient was asymptomatic during the whole follow-up period and tooth exhibited mobility within physiologic limits and was functioning normally.

Absorbable Suture as an Apical Matrix in Single Visit Apexification with Mineral Trioxide Aggregate.

Science.gov (United States)

Goyal, Ayush; Nikhil, Vineeta; Jha, Padmanabh

2016-01-01

Several procedures have been recommended to induce the root end barrier formation in teeth with open apices. Conventional treatment for such cases will require many appointments with an average duration of 12.9 months. During this period, the root canal is susceptible to reinfection from around the provisional restoration, which may promote apical periodontitis and arrest of apical repair. Mineral trioxide aggregate (MTA) has been successfully used for one visit apexification wherein the root canal can be obturated within 24 hours after placement of MTA. Using a matrix prior to the placement of MTA avoids its extrusion, reduces leakage in the sealing material, and allows favorable response of the periapical tissues. This report presents a case of apexification where an absorbable suture was used as an apical matrix. Use of an absorbable suture circumvents all the problems associated with other conventional materials. Conclusion . Placement of the matrix made from the suture material is predictable and is easily positioned at the apex and the length can be adjusted as required. 10-month follow-up of the case shows resorbed matrix and bone healing in the periapical region. The patient was asymptomatic during the whole follow-up period and tooth exhibited mobility within physiologic limits and was functioning normally.

Bundles of spider silk, braided into sutures, resist basic cyclic tests: potential use for flexor tendon repair.

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Kathleen Hennecke

Full Text Available Repair success for injuries to the flexor tendon in the hand is often limited by the in vivo behaviour of the suture used for repair. Common problems associated with the choice of suture material include increased risk of infection, foreign body reactions, and inappropriate mechanical responses, particularly decreases in mechanical properties over time. Improved suture materials are therefore needed. As high-performance materials with excellent tensile strength, spider silk fibres are an extremely promising candidate for use in surgical sutures. However, the mechanical behaviour of sutures comprised of individual silk fibres braided together has not been thoroughly investigated. In the present study, we characterise the maximum tensile strength, stress, strain, elastic modulus, and fatigue response of silk sutures produced using different braiding methods to investigate the influence of braiding on the tensile properties of the sutures. The mechanical properties of conventional surgical sutures are also characterised to assess whether silk offers any advantages over conventional suture materials. The results demonstrate that braiding single spider silk fibres together produces strong sutures with excellent fatigue behaviour; the braided silk sutures exhibited tensile strengths comparable to those of conventional sutures and no loss of strength over 1000 fatigue cycles. In addition, the braiding technique had a significant influence on the tensile properties of the braided silk sutures. These results suggest that braided spider silk could be suitable for use as sutures in flexor tendon repair, providing similar tensile behaviour and improved fatigue properties compared with conventional suture materials.

Sutura arterial com técnicas contínua e de pontos separados, utilizando-se os fios polipropilene e polidioxanone: estudo experimental em coelhos Arterial suture with continuous and interrupted techniques, using polypropylene and polydioxanone threads: experimental study in rabbits

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Nelson Leonardo Kerdahi Leite de Campos

2003-10-01

Full Text Available OBJETIVO: Observar o comportamento da sutura arterial em aortas abdominais de coelhos em crescimento, comparando-se as técnicas contínua e com pontos separados, empregando-se dois tipos de fios: Polipropilene 7-0 (inabsorvível e Polidioxanone 7-0 (absorvível. MÉTODOS: Grupos: GI - Controle (sem sutura; GII - Polipropilene, Pontos Separados; GIII - Polipropilene, Contínua; GIV - Polidioxanone, Pontos Separados e GV - Polidioxanone, Contínua. Cada grupo foi subdividido em quatro Momentos de Eutanásia: aos 7, 14, 30 e 60 dias de pós-operatório. Foram avaliados: peso dos animais, diâmetros e pulsos arteriais, estenose, trombose, aderências, aortografia, visibilidade do fio, cicatrização e microscopia. RESULTADOS: a após 60 dias, o local da linha de sutura cresceu de forma significativa em todos os grupos; b a técnica de sutura com pontos separados causou menor estenose da linha de sutura, observada tanto no ato cirúrgico, como na eutanásia dos animais; c no exame histopatológico, as diferenças encontradas entre grupos foram transitórias, não persistindo após 60 dias de pós-operatório. CONCLUSÃO: O polidioxanone mostrou ser a melhor opção, entre os dois fios, para sutura de artérias em crescimento, pois causa pouca ou nenhuma restrição ao crescimento arterial na linha de sutura, mesmo quando se emprega a técnica contínua.PURPOSE: To assess the arterial suture, comparing continuous and interrupted techniques, in abdominal aorta of growing rabbbits, using two types of suture material: Polypropylene 7-0 (nonabsorbable and Polydioxanone 7-0 (absorbable. METHODS: Groups: GI - Control, without arterial suture; GII - Polypropylene, Interrupted technique; GIII - Polipropilene, Continuous technique; GIV - Polydioxanone, Interrupted technique and GV - Polydioxanone, Continuous technique. Each group was subdivided in four Moments of Euthanasia , according with the number of days after surgery: 7 , 14 , 30 and 60 days. The

Characterization of the bending strength of craniofacial sutures.

Science.gov (United States)

Maloul, Asmaa; Fialkov, Jeffrey; Whyne, Cari M

2013-03-15

The complex, thin and irregular bones of the human craniofacial skeleton (CFS) are connected together through bony articulations and connective tissues. These articulations are known as sutures and are commonly divided into two groups, facial and cranial sutures, based on their location in the CFS. CFS sutures can exhibit highly variable degrees of interdigitation and complexity and are believed to play a role in accommodating the mechanical demands of the skull. This study aimed to evaluate the mechanical behavior of CFS bone samples with and without sutures and to determine the effect of sutural interdigitations on mechanical strength. Sagittal, coronal, frontozygomatic and zygomaticotemporal sutures along with adjacent bone samples not containing sutures were excised from six fresh-frozen cadaveric heads. The interdigitation of the sutures was quantified through μCT based analysis. Three-point bending to failure was performed on a total of 29 samples. The bending strength of bone samples without sutures demonstrated a non-significant increase of 14% as compared to samples containing sutures (P=0.2). The bending strength of bones containing sutures was positively correlated to the sutural interdigitation index (R=0.701, P=0.002). The higher interdigitation indices found in human cranial vs. facial sutures may be present to resist bending loads as a functional requirement in protecting the brain. Copyright © 2012 Elsevier Ltd. All rights reserved.

Water desalination with a single-layer MoS2 nanopore

OpenAIRE

Heiranian, Mohammad; Farimani, Amir Barati; Aluru, Narayana R.

2015-01-01

Efficient desalination of water continues to be a problem facing the society. Advances in nanotechnology have led to the development of a variety of nanoporous membranes for water purification. Here we show, by performing molecular dynamics simulations, that a nanopore in a single-layer molybdenum disulfide can effectively reject ions and allow transport of water at a high rate. More than 88% of ions are rejected by membranes having pore areas ranging from 20 to 60??2. Water flux is found to ...

Comparison of Arterial Repair through the Suture, Suture with Fibrin or Cyanoacrylate Adhesive in Ex-Vivo Porcine Aortic Segment

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Marcus Vinicius H. de Carvalho

Full Text Available Abstract Introduction: Tissue adhesives can be used as adjacent to sutures to drop or avoid bleeding in cardiovascular operations. Objective: To verify the efficiency of fibrin and cyanoacrylate adhesive to seal arterial sutures and if the adhesives penetrate through suture line to the inner of arteries. Methods: 20 abdominal aorta segments of pigs were divided into two groups according to the adhesive which would be used as adjacent to the suture. In every arterial segment an arteriotomy was done, followed by a conventional artery closure. Afterwards a colloidal fluid was injected inside the arterial segment with a simultaneous intravascular pressure monitoring up to a fluid leakage through the suture. This procedure was repeated after application of one of the adhesives on the suture in order to check if the bursting pressure increases. The inner aorta segments also were analyzed in order to check if there was intraluminal adhesive penetration. Results: In Suture 1 group, the mean arterial pressure sustained by the arterial suture reached 86±5.35 mmHg and after the fibrin adhesive application reached 104±11.96 (P<0.002. In the Suture 2 group, the mean arterial pressure sustained by the suture reached 83±2.67 mmHg and after the cyanoacrylate adhesive application reached 152±14.58 mmHg (P<0.002. Intraluminal adhesive penetration has not been noticed. Conclusion: There was a significant rise in the bursting pressure when tissue adhesives were used as adjacent to arterial suture, and this rise was higher if the cyanoacrylate adhesive was used. In addition, the adhesives do not penetrate through the suture line into the arteries.

Developing Cost-Effective Dense Continuous SDC Barrier Layers for SOFCs

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Hoang Viet P.; Hardy, John S.; Coyle, Christopher A.; LU, Zigui; Stevenson, Jeffry W.

2017-12-04

Significantly improved performance during electrochemical testing of a cell with a dense continuous pulsed laser deposited (PLD) samarium doped ceria (SDC) layer spurred investigations into the fabrication of dense continuous SDC barrier layers by means of cost-effective deposition using screen printing which is amenable to industrial production of SOFCs. Many approaches to improve the SDC density have been explored including the use of powder with reduced particle sizes, inks with increased solids loading, and doping with sintering aids (1). In terms of sintering aids, dopants like Mo or binary systems of Mo+Cu or Fe+Co greatly enhance SDC sinterability. In fact, adding dopants to a screen printed, prefired, porous SDC layer made it possible to achieve a dense continuous barrier layer atop the YSZ electrolyte without sintering above 1200°C. Although the objective of fabricating a dense continuous layer was achieved, additional studies have been initiated to improve the cell performance. Underlying issues with constrained sintering and dopant-enhanced ceria-zirconia solid solubility are also addressed in this paper.

Controlling single and few-layer graphene crystals growth in a solid carbon source based chemical vapor deposition

International Nuclear Information System (INIS)

Papon, Remi; Sharma, Subash; Shinde, Sachin M.; Vishwakarma, Riteshkumar; Tanemura, Masaki; Kalita, Golap

2014-01-01

Here, we reveal the growth process of single and few-layer graphene crystals in the solid carbon source based chemical vapor deposition (CVD) technique. Nucleation and growth of graphene crystals on a polycrystalline Cu foil are significantly affected by the injection of carbon atoms with pyrolysis rate of the carbon source. We observe micron length ribbons like growth front as well as saturated growth edges of graphene crystals depending on growth conditions. Controlling the pyrolysis rate of carbon source, monolayer and few-layer crystals and corresponding continuous films are obtained. In a controlled process, we observed growth of large monolayer graphene crystals, which interconnect and merge together to form a continuous film. On the other hand, adlayer growth is observed with an increased pyrolysis rate, resulting few-layer graphene crystal structure and merged continuous film. The understanding of monolayer and few-layer crystals growth in the developed CVD process can be significant to grow graphene with controlled layer numbers.

Roux limb volvulus in laparoscopic Roux-en-Y gastric bypass due to Roux limb stabilization suture: case series.

Science.gov (United States)

Marr, Brendan; Yenumula, Panduranga

2012-01-01

Complications after laparoscopic Roux-en-Y gastric bypass surgery may be related to the type of surgical technique employed. One technique, the placement of a Roux limb stabilization suture, presumably prevents kink at the gastrojejunal anastomosis. However, it can have an adverse effect and we studied a series of cases presenting with intestinal obstruction secondary to this stitch. A retrospective review of a prospectively collected database of laparoscopic Roux-en-Y gastric bypass cases who had reoperations for Roux limb volvulus was performed at a single bariatric center by a single surgeon. Out of 199 patients who underwent laparoscopic Roux en Y gastric bypass with placement of Roux limb stabilization suture, 4 patients (2.01%) presented with Roux limb volvulus postoperatively. BMI was 45.35 ± 2.95. The postoperative time to presentation was 11 ± 10.6 months. All four patients required surgical exploration to reduce the volvulus. In all cases, the Roux limb volvulus was directly attributable to the presence of the stabilization suture. In subsequent 250 cases where this suture was eliminated, there was no volvulus of Roux limb seen. The use of a stabilization suture can result in volvulus of the Roux limb causing intestinal obstruction and this complication can be prevented by avoiding this suture.

Experimental research on the stability of armour and secondary layer in a single layered Tetrapod breakwater

NARCIS (Netherlands)

De Jong, W.; Verhagen, H.J.; Olthof, J.

2004-01-01

Physical model tests were done on an armour of Tetrapods, placed in a single layer. The objective of the investigations was to study the stability of the secondary layer, and to see if the material of this secondary layer could be washed out through the single layer of Tetrapods. It was concluded

Cranial suture biology of the Aleutian Island inhabitants.

Science.gov (United States)

Cray, James; Mooney, Mark P; Siegel, Michael I

2011-04-01

Research on cranial suture biology suggests there is biological and taxonomic information to be garnered from the heritable pattern of suture synostosis. Suture synostosis along with brain growth patterns, diet, and biomechanical forces influence phenotypic variability in cranial vault morphology. This study was designed to determine the pattern of ectocranial suture synostosis in skeletal populations from the Aleutian Islands. We address the hypothesis that ectocranial suture synostosis pattern will differ according to cranial vault shape. Ales Hrdlicka identified two phenotypes in remains excavated from the Aleutian Island. The Paleo-Aleutians, exhibiting a dolichocranic phenotype with little prognathism linked to artifacts distinguished from later inhabitants, Aleutians, who exhibited a brachycranic phenotype with a greater amount of prognathism. A total of 212 crania representing Paleo-Aleuts and Aleutian as defined by Hrdlicka were investigated for suture synostosis pattern following standard methodologies. Comparisons were performed using Guttmann analyses. Results revealed similar suture fusion patterns for the Paleo-Aleut and Aleutian, a strong anterior to posterior pattern of suture fusion for the lateral-anterior suture sites, and a pattern of early termination at the sagittal suture sites for the vault. These patterns were found to differ from that reported in the literature. Because these two populations with distinct cranial shapes exhibit similar patterns of suture synostosis it appears pattern is independent of cranial shape in these populations of Homo sapiens. These findings suggest that suture fusion patterns may be population dependent and that a standardized methodology, using suture fusion to determine age-at-death, may not be applicable to all populations. Copyright © 2011 Wiley-Liss, Inc.

EVALUATION OF ADJUSTABLE SUTURE TECHNIQUE IN OUTCOME OF PTOSIS SURGERY

Directory of Open Access Journals (Sweden)

Nagaraju

2015-10-01

Full Text Available AIM: To evaluate the outcome of adjustable suture technique in ptosis surgery. INTRODUCTION : Surgical management of blepharoptosis is indicated in multiple situations and the post - operative outcomes can be as variable as the indications for surgery. Adjustable suture techniques in ptosis repair have been introduced and variable efficacies have been reported. MATERIALS AND METHODS: A retrospective case review of medical records from June 2010 to May 2011 (12 months of 5 eyes of 5 consecutive patients operated by a single surgeon at a Tertiary Eye care center in South India were reviewed. The clinical profile of patients included was r ecorded and results of adjustable suture technique described by Borman and collegues for these patients was reported. RESULTS: 5 eyes of 5 patients underwent adjustable suture ptosis repair in the study duration. 4 patients with moderate and 1 with severe ptosis, all having good levator function were diagnosed to have c ongenital ptosis in 3 cases and a cquired involutional ptosis in 2 cases. All 5 cases had a satisfactory outcome at day 4 post - operative after adjustment of lid height in the out - patient clini c. 1 patient with acquired involutional ptosis, identified with levator dehiscence intra - operatively had overcorrection at 6 months warranting re - surgery while the other 4 patients had satisfactory cosmetic lid height and functional outcome at 6 months fol low up after the adjustable suture technique for ptosis repair. CONCLUSION: Use of adjustable sutures in ptosis surgery can eliminate the intraoperative lid factors that can lead to unpredictable results. The technique described is easy to adapt and perfor m and can give repeatable and well acceptable results in the properly selected cases

Interaction of discrete and continuous boundary layer modes to cause transition

International Nuclear Information System (INIS)

Durbin, Paul A.; Zaki, Tamer A.; Liu Yang

2009-01-01

The interaction of discrete and continuous Orr-Sommerfeld modes in a boundary layer is studied by computer simulation. The discrete mode is an unstable Tollmien-Schlichting wave. The continuous modes generate jet-like disturbances inside the boundary layer. Either mode alone does not cause transition to turbulence; however, the interaction between them does. The continuous mode jets distort the discrete modes, producing Λ shaped vortices. Breakdown to turbulence is subsequent. The lateral spacing of the Λ's is sometimes the same as the wavelength of the continuous mode, sometimes it differs, depending on the ratio of wavelength to boundary layer thickness.

Bacterial adhesion to suture material in a contaminated wound model: Comparison of monofilament, braided, and barbed sutures.

Science.gov (United States)

Dhom, Jonas; Bloes, Dominik A; Peschel, Andreas; Hofmann, Ulf K

2017-04-01

Contaminated suture material plays an important role in the physiopathology of surgical site infections. Recently, suture material has been developed characterized by barbs projecting from a monofilament base. Claimed advantages for barbed sutures are a shortened wound closure time and reduced maximum wound tension. It has also been suggested that these sutures would be advantageous microbiologically. The aim of this study was to test the microbiological characteristics of the barbed Quill in comparison to the monofilament Ethilon II and the braided sutures Vicryl and triclosan-coated Vicryl Plus. In our study, sutures were cultivated on color-change agar with Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecium, Escherichia coli, and Pseudomonas aeruginosa and the halo size was measured. In a second study arm with longer cultivation bacterial growth was followed by antibiotic treatment. Ethilon II and Quill showed good comparable results, whereas large halos were found around Vicryl. Vicryl Plus results depended on triclosan sensitivity. After longer bacterial cultivation and antibiotic treatment, halos were up to 3.6 times smaller on Quill than on Vicryl (p barbs on Quill. From a microbiological perspective, barbed sutures can be recommended in aseptic surgery, but should only be used carefully in septic surgery. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:925-933, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Vibrational analysis of single-layered graphene sheets

Energy Technology Data Exchange (ETDEWEB)

Sakhaee-Pour, A; Ahmadian, M T [Center of Excellence in Design, Robotics and Automation (CEDRA), Department of Mechanical Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Naghdabadi, R [Department of Mechanical Engineering and Institute for Nano Science and Technology, Sharif University of Technology, Tehran (Iran, Islamic Republic of)], E-mail: sakhaee@alum.sharif.edu, E-mail: naghdabd@sharif.edu

2008-02-27

A molecular structural mechanics method has been implemented to investigate the vibrational behavior of single-layered graphene sheets. By adopting this approach, mode shapes and natural frequencies are obtained. Vibrational analysis is performed with different chirality and boundary conditions. Numerical results from the atomistic modeling are employed to develop predictive equations via a statistical nonlinear regression model. With the proposed equations, fundamental frequencies of single-layered graphene sheets with considered boundary conditions can be predicted within 3% difference with respect to the atomistic simulation.

Postpartum perineal reapir performed by midwives: A randomised trial comparing two suture techniques for perineal repair leaving the skin unsutured

DEFF Research Database (Denmark)

Kindberg, Sara; Misan, Stehouwer; Hvidman, Lone

2008-01-01

Postpartum perineal repair performed by midwives: A randomised trial comparing two suture techniques leaving the skin unsutured. Objective      To compare a continuous suture technique to interrupted stitches using inverted knots for postpartum perineal repair of second-degree lacerations...... and episiotomies.   Design          A double blind randomised controlled trial.   Setting          A Danish university hospital with more than 4800 deliveries annually.   Population   400 healthy primiparous women with a vaginal delivery at term.   Method         Randomisation was computer-controlled. Structured...... healing, patient satisfaction, dyspareunia or need for resuturing. The continuous suture technique was significantly faster (15 min. vs. 17 min, p=0.03) and less suture material was used (1 vs. 2 packets, pskin unsutured...

The European Academy laparoscopic “Suturing Training and Testing’’ (SUTT) significantly improves surgeons’ performance

Science.gov (United States)

Sleiman, Z.; Tanos, V.; Van Belle, Y.; Carvalho, J.L.; Campo, R.

2015-01-01

The efficiency of suturing training and testing (SUTT) model by laparoscopy was evaluated, measuring the suturingskill acquisition of trainee gynecologists at the beginning and at the end of a teaching course. During a workshop organized by the European Academy of Gynecological Surgery (EAGS), 25 participants with three different experience levels in laparoscopy (minor, intermediate and major) performed the 4 exercises of the SUTT model (Ex 1: both hands stitching and continuous suturing, Ex 2: right hand stitching and intracorporeal knotting, Ex 3: left hand stitching and intracorporeal knotting, Ex 4: dominant hand stitching, tissue approximation and intracorporeal knotting). The time needed to perform the exercises is recorded for each trainee and group and statistical analysis used to note the differences. Overall, all trainees achieved significant improvement in suturing time (p psychomotor skills, surgery, teaching, training suturing model. PMID:26977264

The history of barbed sutures.

Science.gov (United States)

Ruff, Gregory L

2013-09-01

Ligatures have been used for millennia to close wounds. Sterilization and synthetic polymers that degrade in a commensurate fashion with wound healing have been the most significant improvements in these age-old devices. However, the constricting loop of a traditional suture and subsequent ischemia ("approximate, don't strangulate") still account for the most common cause of wound dehiscence-necrosis. Inspired by the quill of the North American porcupine, I envisioned a bidirectional array of barbs that could secure tissue without relying on constricting loops. One set of barbs could anchor the other. In this article, I document the development process of these barbed sutures from concept to patent to manufacture and US Food and Drug Administration approval. Knotless, strong, and easy to place, barbed sutures could foreseeably supplant conventional sutures, particularly as endoscopic procedures become more common. They also offer the intriguing potential to suspend ptotic tissues without surgical intervention.

Breakwater stability with damaged single layer armour units

NARCIS (Netherlands)

De Rover, R.; Verhagen, H.J.; Van den Berge, A.; Reedijk, B.

2008-01-01

The effect of single layer interlocking armour unit breakage on the hydraulic armour layer stability and potential damage progression is addressed in this paper. A 2-dimensional scale model of a rubble mound breakwater with an armour layer consisting of Xbloc armour units was tested. The residual

Biomechanical properties of double- and single-row suture anchor repair for surgical treatment of insertional Achilles tendinopathy.

Science.gov (United States)

Beitzel, Knut; Mazzocca, Augustus D; Obopilwe, Elifho; Boyle, James W; McWilliam, James; Rincon, Lina; Dhar, Yasmin; Arciero, Robert A; Amendola, Annunziato

2013-07-01

Because of intratendinous ossifications, retrocalcaneal bursitis, or intratendinous necrosis commonly found in insertional tendinosis, it is often necessary to detach the tendon partially or entirely from its tendon-to-bone junction. Double-row repair for insertional Achilles tendinopathy will generate an increased contact area and demonstrate higher biomechanical stability. Controlled laboratory study. Eighteen cadaver Achilles tendons were split longitudinally and detached, exposing the calcaneus; an ostectomy was performed and the tendon was reattached to the calcaneus in 1 of 2 ways: 2 suture anchors (single row) or a 4-anchor (double row) construct. Footprint area measurements over time, displacement after cyclic loading (2000 cycles), and final load to failure were measured. The double-row refixation technique was statistically superior to the single-row technique in footprint area measurement initially and 5 minutes after repair (P = .009 and P = .01, respectively) but not after 24 hours (P = .713). The double-row construct demonstrated significantly improved measures for peak load (433.9 ± 84.3 N vs 212.0 ± 49.7 N; P = .042), load at yield (354.7 ± 106.2 N vs 198.7 ± 39.5 N; P = .01), and slope (51.8 ± 9.9 N/mm vs 66.7 ± 16.2 N/mm; P = .021). Cyclic loading did not demonstrate significant differences between the 2 constructs. Double-row construct for reinsertion of a completely detached Achilles tendon using proximal and distal rows resulted in significantly larger contact area initially and 5 minutes after repair and led to significantly higher peak load to failure on destructive testing. In treatment for insertional Achilles tendinosis, the tendon often has to be detached and anatomically reattached to its insertion at the calcaneus. To our knowledge there is a lack of biomechanical studies supporting either a number or a pattern of suture anchor fixation. Because the stresses going across the insertion site of the Achilles tendon are significant

Electrically continuous graphene from single crystal copper verified by terahertz conductance spectroscopy and micro four-point probe

DEFF Research Database (Denmark)

Buron, Jonas Christian Due; Pizzocchero, Filippo; Jessen, Bjarke Sørensen

2014-01-01

noninvasive conductance characterization methods: ultrabroadband terahertz time-domain spectroscopy and micro four-point probe, which probe the electrical properties of the graphene film on different length scales, 100 nm and 10 μm, respectively. Ultrabroadband terahertz time-domain spectroscopy allows......- and microscale electrical continuity of single layer graphene grown on centimeter-sized single crystal copper with that of previously studied graphene films, grown on commercially available copper foil, after transfer to SiO2 surfaces. The electrical continuity of the graphene films is analyzed using two....... Micro four-point probe resistance values measured on graphene grown on single crystalline copper in two different voltage-current configurations show close agreement with the expected distributions for a continuous 2D conductor, in contrast with previous observations on graphene grown on commercial...

The suspension (Frost) suture: experience and applications.

Science.gov (United States)

Connolly, Karen L; Albertini, John G; Miller, Christopher J; Ozog, David M

2015-03-01

The Frost suture is a well-known surgical technique for providing upward tension on the lower lid to prevent or correct ectropion after surgical interventions in the periorbital area. Despite its relatively common use, comprehensive information on executing this technique is not readily available. To review eyelid anatomy, indications, and proper technique for performing the Frost suture, as well as potential complications. A review of the literature on Frost sutures was performed. Cadaveric dissection was performed to demonstrate placement of the Frost suture. The Frost suture is a useful method to reduce the risk of ectropion after surgery near the lower eyelid. Downward pull on the lid can occur with normal wound contracture even if ectropion is not present with the initial repair, reinforcing the need for preventive measures. Potential complications of this technique include superficial skin erosion of the upper lid, corneal abrasion, and blockage of the field of vision while the suture is in place.

Visual Measurement of Suture Strain for Robotic Surgery

Directory of Open Access Journals (Sweden)

John Martell

2011-01-01

Full Text Available Minimally invasive surgical procedures offer advantages of smaller incisions, decreased hospital length of stay, and rapid postoperative recovery to the patient. Surgical robots improve access and visualization intraoperatively and have expanded the indications for minimally invasive procedures. A limitation of the DaVinci surgical robot is a lack of sensory feedback to the operative surgeon. Experienced robotic surgeons use visual interpretation of tissue and suture deformation as a surrogate for tactile feedback. A difficulty encountered during robotic surgery is maintaining adequate suture tension while tying knots or following a running anastomotic suture. Displaying suture strain in real time has potential to decrease the learning curve and improve the performance and safety of robotic surgical procedures. Conventional strain measurement methods involve installation of complex sensors on the robotic instruments. This paper presents a noninvasive video processing-based method to determine strain in surgical sutures. The method accurately calculates strain in suture by processing video from the existing surgical camera, making implementation uncomplicated. The video analysis method was developed and validated using video of suture strain standards on a servohydraulic testing system. The video-based suture strain algorithm is shown capable of measuring suture strains of 0.2% with subpixel resolution and proven reliability under various conditions.

Tarmanastomoser kan sys i et enkelt lag i stedet for i to lag--en gennemgang af et Cochranereview

DEFF Research Database (Denmark)

Rosenberg, Jacob; Wara, Pål Edvard

2012-01-01

A recent Cochrane review has shown that bowel anastomoses can be safely performed using a suturing technique with a single layer of sutures rather than a double layer technique. In Denmark, however, relatively few departments use the single layer method as a standard technique. In this paper we...

Post thyroidectomy suture granuloma: a cytological diagnosis.

Science.gov (United States)

Javalgi, Anita P; Arakeri, Surekha U

2013-04-01

There are known post thyroidectomized complications, a suture granuloma being less frequent, with its late complication mimicking recurrent thyroid cancer. A suture granuloma is a benign, granulomatous inflammatory reaction that occurs due to the use of non absorbable suture. It constitutes one of the late complications which altogether make up less than 2% of its incidence. A suture granuloma is similar to a foreign body reaction and it usually develops slowly as a painless, palpable asymptomatic mass over the years. It mimics a cancer recurrence or a lymph node metastasis. Here, we are reporting a case of a post thyroidectomy suture granuloma in a 46 years old lady who presented with a painless swelling in the lateral neck, with a past history of thyroidectomy 5 years back.

Ectocranial suture fusion in primates: pattern and phylogeny.

Science.gov (United States)

Cray, James; Cooper, Gregory M; Mooney, Mark P; Siegel, Michael I

2014-03-01

Patterns of ectocranial suture fusion among Primates are subject to species-specific variation. In this study, we used Guttman Scaling to compare modal progression of ectocranial suture fusion among Hominidae (Homo, Pan, Gorilla, and Pongo), Hylobates, and Cercopithecidae (Macaca and Papio) groups. Our hypothesis is that suture fusion patterns should reflect their evolutionary relationship. For the lateral-anterior suture sites there appear to be three major patterns of fusion, one shared by Homo-Pan-Gorilla, anterior to posterior; one shared by Pongo and Hylobates, superior to inferior; and one shared by Cercopithecidae, posterior to anterior. For the vault suture pattern, the Hominidae groups reflect the known phylogeny. The data for Hylobates and Cercopithecidae groups is less clear. The vault suture site termination pattern of Papio is similar to that reported for Gorilla and Pongo. Thus, it may be that some suture sites are under larger genetic influence for patterns of fusion, while others are influenced by environmental/biomechanic influences. Copyright © 2013 Wiley Periodicals, Inc.

Automatic Detection of Wild-type Mouse Cranial Sutures

DEFF Research Database (Denmark)

Ólafsdóttir, Hildur; Darvann, Tron Andre; Hermann, Nuno V.

, automatic detection of the cranial sutures becomes important. We have previously built a craniofacial, wild-type mouse atlas from a set of 10 Micro CT scans using a B-spline-based nonrigid registration method by Rueckert et al. Subsequently, all volumes were registered nonrigidly to the atlas. Using......, the observer traced the sutures on each of the mouse volumes as well. The observer outperforms the automatic approach by approximately 0.1 mm. All mice have similar errors while the suture error plots reveal that suture 1 and 2 are cumbersome, both for the observer and the automatic approach. These sutures can...

Plasmon resonance in single- and double-layer CVD graphene nanoribbons

DEFF Research Database (Denmark)

Wang, Di; Emani, Naresh K.; Chung, Ting Fung

2015-01-01

Dynamic tunability of the plasmonic resonance in graphene nanoribbons is desirable in the near-infrared. We demonstrated a constant blue shift of plasmonic resonances in double-layer graphene nanoribbons with respect to single-layer graphene nanoribbons. © OSA 2015.......Dynamic tunability of the plasmonic resonance in graphene nanoribbons is desirable in the near-infrared. We demonstrated a constant blue shift of plasmonic resonances in double-layer graphene nanoribbons with respect to single-layer graphene nanoribbons. © OSA 2015....

Tendoscopic Double-Row Suture Bridge Peroneal Retinaculum Repair for Recurrent Dislocation of Peroneal Tendons in the Ankle.

Science.gov (United States)

Nishimura, Akinobu; Nakazora, Shigeto; Ito, Naoya; Fukuda, Aki; Kato, Ko; Sudo, Akihiro

2016-06-01

Traumatic dislocation of peroneal tendons in the ankle is an uncommon lesion that mainly affects young adults. Unfortunately, most cases lead to recurrent dislocation of the peroneal tendons of the ankle (RPTD). Therefore, most cases need operative treatment. One of the most common operative procedures is superior peroneal retinaculum (SPR) repair. Recently, surgery for RPTD has been achieved with less invasive arthroscopic procedures. In this article, tendoscopic surgery for RPTD using a double-row suture bridge technique is introduced. This technique consists of debridement of the lateral aspect of the fibula under an intrasheath pseudo-cavity, suture anchor insertion into the fibular ridge, and reattachment of the SPR to the fibula using a knotless anchor screwed into the lateral aspect of the fibula. This technique mimics the double-row suture bridge technique for rotator cuff tear repair. The double-row suture bridge technique requires more surgical steps than the single-row technique, but it provides a wider bone-SPR contact surface and tighter fixation than the single-row technique. This procedure is an attractive option because it is less invasive and has achieved results similar to open procedures.

Frequency of Dehiscence in Hand-Sutured and Stapled Intestinal Anastomoses in Dogs.

Science.gov (United States)

Duell, Jason R; Thieman Mankin, Kelley M; Rochat, Mark C; Regier, Penny J; Singh, Ameet; Luther, Jill K; Mison, Michael B; Leeman, Jessica J; Budke, Christine M

2016-01-01

To determine the frequency of dehiscence of hand-sutured and stapled intestinal anastomoses in the dog and compare the surgery duration for the methods of anastomosis. Historical cohort study. Two hundred fourteen client-owned dogs undergoing hand-sutured (n = 142) or stapled (n = 72) intestinal anastomoses. Medical records from 5 referral institutions were searched for dogs undergoing intestinal resection and anastomosis between March 2006 and February 2014. Demographic data, presence of septic peritonitis before surgery, surgical technique (hand-sutured or stapled), surgery duration, surgeon (resident versus faculty member), indication for surgical intervention, anatomic location of resection and anastomosis, and if dehiscence was noted postoperatively were retrieved. Estimated frequencies were summarized and presented as proportions and 95% confidence intervals (CI) and continuous outcomes as mean (95% CI). Comparisons were made across methods of anastomosis. Overall, 29/205 dogs (0.14, 95% CI 0.10-00.19) had dehiscence, including 21/134 dogs (0.16, 0.11-0.23) undergoing hand-sutured anastomosis and 8/71 dogs (0.11, 0.06-0.21) undergoing stapled anastomosis. There was no significant difference in the frequency of dehiscence across anastomosis methods (χ(2), P = .389). The mean (95% CI) surgery duration of 140 minutes (132-147) for hand- sutured anastomoses and 108 minutes (99-119) for stapled anastomoses was significantly different (t-test, P < .001). No significant difference in frequency of dehiscence was noted between hand- sutured and stapled anastomoses in dogs but surgery duration is significantly reduced by the use of staples for intestinal closure. © Copyright 2015 by The American College of Veterinary Surgeons.

White-light-emitting diode based on a single-layer polymer

Science.gov (United States)

Wang, B. Z.; Zhang, X. P.; Liu, H. M.

2013-05-01

A broad-band light-emitting diode was achieved in a single-layer device based on pure poly(9,9'-dioctylfluorene-co-bis-N,N'-(4-butylphenyl)-bis-N,N'-phenyl-1,4-phenylenediamine) (PFB). Electromer emission was observed in the red with a center wavelength of about 620 nm in electroluminescence (EL) spectrum. This kind of emission exhibits strong dependence on the thickness of the PFB layer, so that the shape of the EL spectrum may be adjusted through changing the thickness of the active polymer layer to balance between the intrinsic PFB emission in the blue and the electromer emission in the red. Thus, white light emission may be achieved from such a single-layer single-material diode.

Bandgap tunability at single-layer molybdenum disulphide grain boundaries

KAUST Repository

Huang, Yu Li

2015-02-17

Two-dimensional transition metal dichalcogenides have emerged as a new class of semiconductor materials with novel electronic and optical properties of interest to future nanoelectronics technology. Single-layer molybdenum disulphide, which represents a prototype two-dimensional transition metal dichalcogenide, has an electronic bandgap that increases with decreasing layer thickness. Using high-resolution scanning tunnelling microscopy and spectroscopy, we measure the apparent quasiparticle energy gap to be 2.40±0.05 eV for single-layer, 2.10±0.05 eV for bilayer and 1.75±0.05 eV for trilayer molybdenum disulphide, which were directly grown on a graphite substrate by chemical vapour deposition method. More interestingly, we report an unexpected bandgap tunability (as large as 0.85±0.05 eV) with distance from the grain boundary in single-layer molybdenum disulphide, which also depends on the grain misorientation angle. This work opens up new possibilities for flexible electronic and optoelectronic devices with tunable bandgaps that utilize both the control of two-dimensional layer thickness and the grain boundary engineering.

Fiber from ramie plant (Boehmeria nivea): A novel suture biomaterial

Energy Technology Data Exchange (ETDEWEB)

Kandimalla, Raghuram; Kalita, Sanjeeb; Choudhury, Bhaswati [Drug discovery laboratory, Institute of Advanced Study in Science and Technology, Guwahati, Assam 781035 (India); Devi, Dipali [Seri biotech laboratory, Institute of Advanced Study in Science and Technology, Guwahati, Assam 781035 (India); Kalita, Dhaneswar [Government Ayurvedic College and Hospital, Jalukbari, Guwahati, Assam 781014 (India); Kalita, Kasturi [Department of Pathology, Hayat Hospital, Guwahati, Assam 781034 (India); Dash, Suvakanta [Girijananda Chowdhury Institute of pharmaceutical science, Azara, Guwahati, Assam 781017 (India); Kotoky, Jibon, E-mail: jkotoky@gmail.com [Drug discovery laboratory, Institute of Advanced Study in Science and Technology, Guwahati, Assam 781035 (India)

2016-05-01

The quest for developing an ideal suture material prompted our interest to develop a novel suture with advantageous characters to market available ones. From natural origin only silk, cotton and linen fibers are presently available in market as non-absorbable suture biomaterials. In this study, we have developed a novel, cost-effective, and biocompatible suture biomaterial from ramie plant, Boehmeria nivea fiber. Field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and thermo gravimetric analysis (TGA) results revealed the physicochemical properties of raw and degummed ramie fiber, where the former one showed desirable characteristics for suture preparation. The braided multifilament ramie suture prepared from degummed fiber exhibited excellent tensile strength. The suture found to be biocompatible towards human erythrocytes and nontoxic to mammalian cells. The fabricated ramie suture exhibited significant antibacterial activity against Escherichia coli, Bacillus subtilis and Staphylococcus aureus; which can be attributed to the inherent bacteriostatic ability of ramie plant fiber. In vivo wound closure efficacy was evaluated in adult male wister rats by suturing the superficial wound incisions. Within seven days of surgery the wound got completely healed leaving no rash and scar. The role of the ramie suture in complete wound healing was supported by the reduced levels of serum inflammatory mediators. Histopathology studies confirmed the wound healing ability of ramie suture, as rapid synthesis of collagen, connective tissue and other skin adnexal structures were observed within seven days of surgery. Tensile properties, biocompatibility and wound closure efficacy of the ramie suture were comparable with market available BMSF suture. The outcome of this study can drive tremendous possibility for the utilization of ramie plant fiber for

Fiber from ramie plant (Boehmeria nivea): A novel suture biomaterial

International Nuclear Information System (INIS)

Kandimalla, Raghuram; Kalita, Sanjeeb; Choudhury, Bhaswati; Devi, Dipali; Kalita, Dhaneswar; Kalita, Kasturi; Dash, Suvakanta; Kotoky, Jibon

2016-01-01

The quest for developing an ideal suture material prompted our interest to develop a novel suture with advantageous characters to market available ones. From natural origin only silk, cotton and linen fibers are presently available in market as non-absorbable suture biomaterials. In this study, we have developed a novel, cost-effective, and biocompatible suture biomaterial from ramie plant, Boehmeria nivea fiber. Field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and thermo gravimetric analysis (TGA) results revealed the physicochemical properties of raw and degummed ramie fiber, where the former one showed desirable characteristics for suture preparation. The braided multifilament ramie suture prepared from degummed fiber exhibited excellent tensile strength. The suture found to be biocompatible towards human erythrocytes and nontoxic to mammalian cells. The fabricated ramie suture exhibited significant antibacterial activity against Escherichia coli, Bacillus subtilis and Staphylococcus aureus; which can be attributed to the inherent bacteriostatic ability of ramie plant fiber. In vivo wound closure efficacy was evaluated in adult male wister rats by suturing the superficial wound incisions. Within seven days of surgery the wound got completely healed leaving no rash and scar. The role of the ramie suture in complete wound healing was supported by the reduced levels of serum inflammatory mediators. Histopathology studies confirmed the wound healing ability of ramie suture, as rapid synthesis of collagen, connective tissue and other skin adnexal structures were observed within seven days of surgery. Tensile properties, biocompatibility and wound closure efficacy of the ramie suture were comparable with market available BMSF suture. The outcome of this study can drive tremendous possibility for the utilization of ramie plant fiber for

Characterization of craniofacial sutures using the finite element method.

Science.gov (United States)

Maloul, Asmaa; Fialkov, Jeffrey; Wagner, Diane; Whyne, Cari M

2014-01-03

Characterizing the biomechanical behavior of sutures in the human craniofacial skeleton (CFS) is essential to understand the global impact of these articulations on load transmission, but is challenging due to the complexity of their interdigitated morphology, the multidirectional loading they are exposed to and the lack of well-defined suture material properties. This study aimed to quantify the impact of morphological features, direction of loading and suture material properties on the mechanical behavior of sutures and surrounding bone in the CFS. Thirty-six idealized finite element (FE) models were developed. One additional specimen-specific FE model was developed based on the morphology obtained from a µCT scan to represent the morphological complexity inherent in CFS sutures. Outcome variables of strain energy (SE) and von Mises stress (σvm) were evaluated to characterize the sutures' biomechanical behavior. Loading direction was found to impact the relationship between SE and interdigitation index and yielded varied patterns of σvm in both the suture and surrounding bone. Adding bone connectivity reduced suture strain energy and altered the σvm distribution. Incorporating transversely isotropic material properties was found to reduce SE, but had little impact on stress patterns. High-resolution µCT scanning of the suture revealed a complex morphology with areas of high and low interdigitations. The specimen specific suture model results were reflective of SE absorption and σvm distribution patterns consistent with the simplified FE results. Suture mechanical behavior is impacted by morphologic factors (interdigitation and connectivity), which may be optimized for regional loading within the CFS. © 2013 Elsevier Ltd. All rights reserved.

Combination of intracostal sutures with muscle flap to decrease post thoracotomy pain: A single blinded randomized clinical trial.

Science.gov (United States)

Montazer, Majid; Hashemzade, Shahryar; Gargari, Reza Movassaghi; Ramouz, Ali; Sanaie, Sarvin; Rasihashemi, Seyed Ziaeddin

2017-01-01

To assess the efficacy of intercostal nerve protection by intercostal muscle (ICM) flap in post-thoracotomy pain improvement compared to intracostal suturing. In a randomized controlled trial, ninety-four patients undergoing posterolateral thoracotomy surgery were divided into two subgroups. Intracostal sutures in isolation and in combination with ICM flap techniques were used for thoracotomy closure in both groups. Numeric Pain Scale and Visual Pain Scale as pain scores were assessed on the first, second, third, fourth, fifth, sixth and seventh postoperative days and follow-up visits during the 2 nd week, 1 st , 2 nd , 4 th and 6 th months after thoracotomy. Out of 94 patients, 58 were male and 36 were females. While the mean age of patients in intracostal group was 45.3 ± 17.6 years, it was 47.4 ± 16.1 years in intracostal plus ICM flap group. The mean operation time for the first group was 191.0 ± 74.7 minutes, while it was 219.3 ± 68.8 minutes in the second (p>0.05). Numeric rating score and visual pain scale did not demonstrate any significant difference in pain severity on postoperative days and follow-up visits between both groups (p>0.05). Although the trend of pain reduction was significant in each group (p0.001). Intracostal sutures in combination with muscle flap did not reduce postoperative pain in thoracotomy compared with intracostal sutures alone in thoracotomy closure.

An easier method for performing a pancreaticojejunostomy for the soft pancreas using a fast-absorbable suture

Institute of Scientific and Technical Information of China (English)

Kenichi Hakamada; Shunji Narumi; Yoshikazu Toyoki; Masaki Nara; Kenosuke Ishido; Takuya Miura; Norihito; Mutsuo Sasaki

2008-01-01

AIM:To clarify the usefulness of a new method for performing a pancreaticojejunostomy by using a fastabsorbable suture material irradiated polyglactin 910,and a temporary stent tube for a narrow pancreatic duct with a soft pancreatic texture.METHODS:Among 63 consecutive patients with soft pancreas undergoing a pancreaticoduodenectomy from 2003 to 2006,35 patients were treated with a new reconstructive method.Briefly,after the pancreatic transaction,a stent tube was inserted into the lumen of the pancreatic duct and ligated with it by a fastabsorbable suture.Another tip of the stent tube was introduced into the intestinal lumen at the jejunal limb,where a purse-string suture was made by another fast-absorbable suture to roughly fix the tube.The pancreaticojejunostomy was completed by ligating two fast-absorbable sutures to approximate the ductal end and the jejunal mucosa,and by adding a rough anastomosis between the pancreatic parenchyma and the seromuscular layer of the jejunum.The initial surgical results with this method were retrospectively compared with those of the 28 patients treated with conventional duct-to-mucosa anastomosis.RESULTS:The incidences of postoperative morbidity including pancreatic fistula were comparable between the two groups (new;3%-17% vs conventional;7%-14% according to the definitions).There was no mortality and re-admission.Late complications were also rarely seen.CONCLUSION:A pancreaticojejunostomy using an irradiated polyglactin 910 suture material and a temporary stent is easy to perform and is feasible even in cases with a narrow pancreatic duct and a normal soft pancreas.

Midwives conducting perineal repair: The Danish Suture Trial

DEFF Research Database (Denmark)

Kindberg, Sara

2007-01-01

Midwives conducting perineal repair: The Danish Suture Trial.     Background Suture techniques and materials for repair of 2nd degree perineal lacerations and episiotomies have been tested in several clinical trials. Danish midwives and obstetricians have developed a new, simple and time-efficien......Midwives conducting perineal repair: The Danish Suture Trial.     Background Suture techniques and materials for repair of 2nd degree perineal lacerations and episiotomies have been tested in several clinical trials. Danish midwives and obstetricians have developed a new, simple and time...

Optical and Electrical Characteristics of Graphene Double Layer Formed by a Double Transfer of Graphene Single Layers.

Science.gov (United States)

Kim, Young Jun; Bae, Gi Yoon; Chun, Sungwoo; Park, Wanjun

2016-03-01

We demonstrate formation of double layer graphene by means of a double transfer using two single graphene layers grown by a chemical vapor deposition method. It is observed that shiftiness and broadness in the double-resonance of Raman scattering are much weaker than those of bilayer graphene formed naturally. Transport characteristics examined from transmission line measurements and field effect transistors show the similar behavior with those of single layer graphene. It indicates that interlayer separation, in electrical view, is large enough to avoid correlation between layers for the double layer structure. It is also observed from a transistor with the double layer graphene that molecules adsorpted on two inner graphene surfaces in the double layered structure are isolated and conserved from ambient environment.

21 CFR 878.4830 - Absorbable surgical gut suture.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Absorbable surgical gut suture. 878.4830 Section 878.4830 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... surgical gut suture. (a) Identification. An absorbable surgical gut suture, both plain and chromic, is an...

Bridge Suture for Successful McDonald Emergency Cerclage.

Science.gov (United States)

Tanaka, Masaaki; Hori, Yoshiaki; Shirafuji, Aya; Kato, Mitsunori; Kato, Jyun; Kobayashi, Hiroto; Tsuchida, Toru; Fukae, Tsukasa

2017-01-01

To create awareness about a surgical technique termed bridge suture, which is performed as a pretreatment before a McDonald cerclage is performed on an emergency to treat severe cervical insufficiency. Procedures for bridge suture were reviewed in detail and outcomes of 16 patients treated with bridge suture followed by McDonald cerclage were evaluated retrospectively. Using the bridge suture, the edges of uterine cervix were temporarily sutured and the external uterine os was closed, while the hourglass-shaped fetal membranes were concomitantly confined within the cervix; subsequently, a McDonald cerclage was performed. Over a 22-year period, 16 patients with a dilated cervix and bulging fetal membranes were treated using the technique of bridge suture followed by an emergency cerclage. The mean gestational age at cerclage was 22.5 weeks; the mean gestational age at delivery was 30.7 weeks; and the mean interval between cerclage and delivery was 8.2 weeks. In 15 out of 16 cases, cerclage was performed without encountering any complications. No maternal complications, including cervical laceration, were observed. The mean body weight of 17 neonates, including that of a twin, was 1,516 g and of them, 15 neonates survived. The important outcome of bridge suture is the replacement of fetal membranes back into the uterine cavity before McDonald's cerclage is performed. Pretreatment with bridge suture may facilitate the performance of a successful emergency cerclage and contribute to good maternal and neonatal outcomes. © 2016 S. Karger AG, Basel.

Biomechanical Comparison of Modified Suture Bridge Using Rip-Stop versus Traditional Suture Bridge for Rotator Cuff Repair

Directory of Open Access Journals (Sweden)

ZiYing Wu

2016-01-01

Full Text Available Purpose. To compare the biomechanical properties of 3 suture-bridge techniques for rotator cuff repair. Methods. Twelve pair-matched fresh-frozen shoulder specimens were randomized to 3 groups of different repair types: the medially Knotted Suture Bridge (KSB, the medially Untied Suture Bridge (USB, and the Modified Suture Bridge (MSB. Cyclic loading and load-to-failure test were performed. Parameters of elongation, stiffness, load at failure, and mode of failure were recorded. Results. The MSB technique had the significantly greatest load to failure (515.6±78.0 N, P=0.04 for KSB group; P<0.001 for USB group, stiffness (58.0±10.7 N/mm, P=0.005 for KSB group; P<0.001 for USB group, and lowest elongation (1.49±0.39 mm, P=0.009 for KSB group; P=0.001 for USB group among 3 groups. The KSB repair had significantly higher ultimate load (443.5±65.0 N than USB repair (363.5±52.3 N, P=0.024. However, there was no statistical difference in stiffness and elongation between KSB and USB technique (P=0.396 for stiffness and P=0.242 for elongation, resp.. The failure mode for all specimens was suture pulling through the cuff tendon. Conclusions. Our modified suture bridge technique (MSB may provide enhanced biomechanical properties when compared with medially knotted or knotless repair. Clinical Relevance. Our modified technique may represent a promising alternative in arthroscopic rotator cuff repair.

Tension-releasing suture appendage on single-incision sling device: A novel approach to postoperative voiding dysfunctions

Directory of Open Access Journals (Sweden)

Tsia-Shu Lo

2016-08-01

Conclusion: Tension-releasing suture is effective in the management of immediate postoperative voiding dysfunction in an SIS procedure. SIS operation has good short-term objective and subjective cure rates for female urodynamic stress incontinence.

Complications with mechanical suture use in colorectal surgery

International Nuclear Information System (INIS)

Bruno, G.; Ruso, L.; Gatti, A.; Quiros, F.; Balboa, O.

1998-01-01

The great development of mechanical suture and its qualitative impact in colorectal surgery has not been able to avoid persistent mortality due to suture failure which is still about 5% and rectal stenosis, which is significantly higher than with manual sutures.The present paper analyses 63 cases of colorrectal anastomosis performed of coordination with mechanical suture at CASMU, in a period of four years (1991-1995).There were 51 rectum resections and colorrectal anastomosis and 12 reconstruction of intestinal transit.There were 28 females and 35 males with and average age of 66 years.Three patients died (4,7%), 20 (31,7%) suffered various complications among which some are pointed out in relation to mechanical suture to suture failures(3,1%) who died and 8 rectal stenosis(12,9%)with favourable evolution after dilations.The authors analyse the issues that incide on the production of complications in colorrectal surgery and conclude that the incidence of global complications in their series is elevated, although mortality, suture failure and rectal stenosis figures are comparable to those in international literature analysed.The incidence of machine width proximal ostomies and radiotherapy on the development of stenosis in our milieu require a multicentric studie with a greater number of patients

The Effect of Single Pyramidal Neuron Firing Within Layer 2/3 and Layer 4 in Mouse V1.

Science.gov (United States)

Meyer, Jochen F; Golshani, Peyman; Smirnakis, Stelios M

2018-01-01

The influence of cortical cell spiking activity on nearby cells has been studied extensively in vitro . Less is known, however, about the impact of single cell firing on local cortical networks in vivo . In a pioneering study, Kwan and Dan (Kwan and Dan, 2012) reported that in mouse layer 2/3 (L2/3), under anesthesia , stimulating a single pyramidal cell recruits ~2.1% of neighboring units. Here we employ two-photon calcium imaging in layer 2/3 of mouse V1, in conjunction with single-cell patch clamp stimulation in layer 2/3 or layer 4, to probe, in both the awake and lightly anesthetized states , how (i) activating single L2/3 pyramidal neurons recruits neighboring units within L2/3 and from layer 4 (L4) to L2/3, and whether (ii) activating single pyramidal neurons changes population activity in local circuit. To do this, it was essential to develop an algorithm capable of quantifying how sensitive the calcium signal is at detecting effectively recruited units ("followers"). This algorithm allowed us to estimate the chance of detecting a follower as a function of the probability that an epoch of stimulation elicits one extra action potential (AP) in the follower cell. Using this approach, we found only a small fraction (layer-2/3 or layer-4 pyramidal neurons produces few (<1% of local units) reliable single-cell followers in L2/3 of mouse area V1, either under light anesthesia or in quiet wakefulness: instead, single cell stimulation was found to elevate aggregate population activity in a weak but highly distributed fashion.

Single track and single layer formation in selective laser melting of niobium solid solution alloy

Directory of Open Access Journals (Sweden)

Yueling GUO

2018-04-01

Full Text Available Selective laser melting (SLM was employed to fabricate Nb-37Ti-13Cr-2Al-1Si (at% alloy, using pre-alloyed powders prepared by plasma rotating electrode processing (PREP. A series of single tracks and single layers under different processing parameters was manufactured to evaluate the processing feasibility by SLM, including laser power, scanning speed, and hatch distance. Results showed that continuous single tracks could be fabricated using proper laser powers and scanning velocities. Both the width of a single track and its penetration depth into a substrate increased with an increase of the linear laser beam energy density (LED, i.e., an increase of the laser power and a decrease of the scanning speed. Nb, Ti, Si, Cr, and Al elements distributed heterogeneously over the melt pool in the form of swirl-like patterns. An excess of the hatch distance was not able to interconnect neighboring tracks. Under improper processing parameters, a balling phenomenon occurred, but could be eliminated with an increased LED. This work testified the SLM-processing feasibility of Nb-based alloy and promoted the application of SLM to the manufacture of niobium-based alloys. Keywords: Additive manufacturing, Melt pool, Niobium alloy, Powder metallurgy, Selective laser melting

Electrically continuous graphene from single crystal copper verified by terahertz conductance spectroscopy and micro four-point probe

DEFF Research Database (Denmark)

Buron, Jonas Christian Due; Pizzocchero, Filippo; Jessen, Bjarke Sørensen

2014-01-01

The electrical performance of graphene synthesized by chemical vapor deposition and transferred to insulating surfaces may be compromised by extended defects, including for instance grain boundaries, cracks, wrinkles, and tears. In this study, we experimentally investigate and compare the nano......- and microscale electrical continuity of single layer graphene grown on centimeter-sized single crystal copper with that of previously studied graphene films, grown on commercially available copper foil, after transfer to SiO2 surfaces. The electrical continuity of the graphene films is analyzed using two...... for measurement of the complex conductance response in the frequency range 1-15 terahertz, covering the entire intraband conductance spectrum, and reveals that the conductance response for the graphene grown on single crystalline copper intimately follows the Drude model for a barrier-free conductor. In contrast...

Cauterization technique for suture erosion in transscleralfixation of intraocular lenses

Directory of Open Access Journals (Sweden)

Xu-Ting Hu

2013-12-01

Full Text Available Transscleral suturing is a commonly applied technique to fix intraocular implants in the sulcus. A major problem after transscleral implantation is suture erosion that normally happens in the late post-surgery period and may result in an increased incidence of endophthalmitis. Here we describe an original cauterization method by using a glass rod to melt the exposed suture end without damaging the suture knot in the sclera to avoid suture exposure in sclera-fixed IOL implantation. This is a simple, quick and effective technique that can be performed without conjunctiva incisions and will help to reduce suture erosion related complications.

Subcuticular Suture Technique: Alternative to Frost Suture to Prevent Ectropion After Transcutaneous Incision of Lower Eyelid.

Science.gov (United States)

Kudva, Adarsh; Kamath, Abhay; Cariappa, K M; Gadicherla, Srikanth; Dhara, B Vasantha

2017-12-01

An ectropion is a complication that can arise from reconstruction in the infraorbital region. Often, this complication occurs despite proper positioning of the lower lid at the time of closure. Various transcutaneous approaches to orbit skeleton have investigated in view of complication arising from them. A subtarsal approach with a postoperative Frost suture gives an advantage to reduce the occurrence of ectropion especially after treatment of orbital floor fractures. This case describes a method of subcuticular suturing technique for subtarsal incision of lower lid which can be used to support the lid during healing period, thus decreasing the rate of ectropion. The technique described here is an alterative method for frost suturing with certain advantages.

Organic photovoltaic devices with a single layer geometry (Conference Presentation)

Science.gov (United States)

Kolesov, Vladimir A.; Fuentes-Hernandez, Canek; Aizawa, Naoya; Larrain, Felipe A.; Chou, Wen-Fang; Perrotta, Alberto; Graham, Samuel; Kippelen, Bernard

2016-09-01

Organic photovoltaics (OPV) can lead to a low cost and short energy payback time alternative to existing photovoltaic technologies. However, to fulfill this promise, power conversion efficiencies must be improved and simultaneously the architecture of the devices and their processing steps need to be further simplified. In the most efficient devices to date, the functions of photocurrent generation, and hole/electron collection are achieved in different layers adding complexity to the device fabrication. In this talk, we present a novel approach that yields devices in which all these functions are combined in a single layer. Specifically, we report on bulk heterojunction devices in which amine-containing polymers are first mixed in the solution together with the donor and acceptor materials that form the active layer. A single-layer coating yields a self-forming bottom electron-collection layer comprised of the amine-containing polymer (e.g. PEIE). Hole-collection is achieved by subsequent immersion of this single layer in a solution of a polyoxometalate (e.g. phosphomolybdic acid (PMA)) leading to an electrically p-doped region formed by the diffusion of the dopant molecules into the bulk. The depth of this doped region can be controlled with values up to tens of nm by varying the immersion time. Devices with a single 500 nm-thick active layer of P3HT:ICBA processed using this method yield power conversion efficiency (PCE) values of 4.8 ± 0.3% at 1 sun and demonstrate a performance level superior to that of benchmark three-layer devices with separate layers of PEIE/P3HT:ICBA/MoOx (4.1 ± 0.4%). Devices remain stable after shelf lifetime experiments carried-out at 60 °C over 280 h.

Tensile strength and failure load of sutures for robotic surgery.

Science.gov (United States)

Abiri, Ahmad; Paydar, Omeed; Tao, Anna; LaRocca, Megan; Liu, Kang; Genovese, Bradley; Candler, Robert; Grundfest, Warren S; Dutson, Erik P

2017-08-01

Robotic surgical platforms have seen increased use among minimally invasive gastrointestinal surgeons (von Fraunhofer et al. in J Biomed Mater Res 19(5):595-600, 1985. doi: 10.1002/jbm.820190511 ). However, these systems still suffer from lack of haptic feedback, which results in exertion of excessive force, often leading to suture failures (Barbash et al. in Ann Surg 259(1):1-6, 2014. doi: 10.1097/SLA.0b013e3182a5c8b8 ). This work catalogs tensile strength and failure load among commonly used sutures in an effort to prevent robotic surgical consoles from exceeding identified thresholds. Trials were thus conducted on common sutures varying in material type, gauge size, rate of pulling force, and method of applied force. Polydioxanone, Silk, Vicryl, and Prolene, gauges 5-0 to 1-0, were pulled till failure using a commercial mechanical testing system. 2-0 and 3-0 sutures were further tested for the effect of pull rate on failure load at rates of 50, 200, and 400 mm/min. 3-0 sutures were also pulled till failure using a da Vinci robotic surgical system in unlooped, looped, and at the needle body arrangements. Generally, Vicryl and PDS sutures had the highest mechanical strength (47-179 kN/cm 2 ), while Silk had the lowest (40-106 kN/cm 2 ). Larger diameter sutures withstand higher total force, but finer gauges consistently show higher force per unit area. The difference between material types becomes increasingly significant as the diameters decrease. Comparisons of identical suture materials and gauges show 27-50% improvement in the tensile strength over data obtained in 1985 (Ballantyne in Surg Endosc Other Interv Tech 16(10):1389-1402, 2002. doi: 10.1007/s00464-001-8283-7 ). No significant differences were observed when sutures were pulled at different rates. Reduction in suture strength appeared to be strongly affected by the technique used to manipulate the suture. Availability of suture tensile strength and failure load data will help define software safety

Comparing the Use of 3D Photogrammetry and Computed Tomography in Assessing the Severity of Single-Suture Nonsyndromic Craniosynostosis.

Science.gov (United States)

Ho, Olivia A; Saber, Nikoo; Stephens, Derek; Clausen, April; Drake, James; Forrest, Christopher; Phillips, John

2017-05-01

Single-suture nonsyndromic craniosynostosis is diagnosed using clinical assessment and computed tomography (CT). With increasing awareness of the associated risks of radiation exposure, the use of CT is particularly concerning in patients with craniosynostosis since they are exposed at a younger age and more frequently than the average child. Three-dimensional (3D) photogrammetry is advantageous-it involves no radiation, is conveniently obtainable within clinic, and does not require general anaesthesia. This study aims to assess how 3D photogrammetry compares to CT in the assessment of craniosynostosis severity, to quantify surgical outcomes, and analyze the validity of 3D photogrammetry in craniosynostosis. Computed tomography images and 3D photographs of patients who underwent craniosynostosis surgery were assessed and aligned to best fit. The intervening area between the CT and 3D photogrammetry curves at the supraorbital bar (bandeau) level in axial view was calculated. Statistical analysis was performed using Student t test. Ninety-five percent confidence intervals were determined and equivalence margins were applied. In total, 41 pairs of CTs and 3D photographs were analyzed. The 95% confidence interval was 198.16 to 264.18 mm 2 and the mean was 231.17 mm 2 . When comparisons were made in the same bandeau region omitting the temporalis muscle, the 95% confidence interval was 108.94 to 147.38 mm 2 , and the mean was 128.16 mm 2 . Although statistically significant difference between the modalities was found, they can be attributable to the dampening effect of soft tissue. Within certain error margins, 3D photogrammetry is comparable to CT in assessing the severity of single-suture nonsyndromic craniosynostosis. However, a dampening effect can be attributable to the soft tissue. Three-dimensional photogrammetry may be more applicable for severe cases of craniosynostosis but not milder deformity. It may also be beneficial for assessing the overall appearance and

Tunable phase transition in single-layer TiSe2 via electric field

Science.gov (United States)

Liu, Lei; Zhuang, Houlong L.

2018-06-01

Phase transition represents an intriguing physical phenomenon that exists in a number of single-layer transition-metal dichalcogenides. This phenomenon often occurs below a critical temperature and breaks the long-range crystalline order leading to a reconstructed superstructure called the charge-density wave (CDW) structure, which can therefore be recovered by external stimuli such as temperature. Alternatively, we show here that another external stimulation, electric field can also result in the phase transition between the regular and CDW structures of a single-layer transition-metal dichalcogenide. We used single-layer TiSe2 as an example to elucidate the mechanism of the CDW followed by calculations of the electronic structure using a hybrid density functional. We found that applying electric field can tune the phase transition between the 1T and CDW phases of single-layer TiSe2. Our work opens up a route of tuning the phase transition of single-layer materials via electric field.

Comparison of stress in single and multiple layer depositions of plasma-deposited amorphous silicon dioxide

International Nuclear Information System (INIS)

Au, V; Charles, C; Boswell, R W

2006-01-01

The stress in a single-layer continuous deposition of amorphous silicon dioxide (SiO 2 ) film is compared with the stress within multiple-layer intermittent or 'stop-start' depositions. The films were deposited by helicon activated reactive evaporation (plasma assisted deposition with electron beam evaporation source) to a 1 μm total film thickness. The relationships for stress as a function of film thickness for single, two, four and eight layer depositions have been obtained by employing the substrate curvature technique on a post-deposition etch-back of the SiO 2 film. At film thicknesses of less than 300 nm, the stress-thickness relationships clearly show an increase in stress in the multiple-layer samples compared with the relationship for the single-layer film. By comparison, there is little variation in the film stress between the samples when it is measured at 1 μm film thickness. Localized variations in stress were not observed in the regions where the 'stop-start' depositions occurred. The experimental results are interpreted as a possible indication of the presence of unstable, strained Si-O-Si bonds in the amorphous SiO 2 film. It is proposed that the subsequent introduction of a 'stop-start' deposition process places additional strain on these bonds to affect the film structure. The experimental stress-thickness relationships were reproduced independently by assuming a linear relationship between the measured bow and film thickness. The constants of the linear model are interpreted as an indication of the density of the amorphous film structure

Adhesive strip wound closure after thyroidectomy/parathyroidectomy: a prospective, randomized controlled trial.

LENUS (Irish Health Repository)

O'Leary, D Peter

2013-03-01

Conventional collar incision closure in thyroid and parathyroid surgery involves the insertion of an epidermal layer of subcutaneous absorbable sutures that are reinforced by a deep layer of sutures. Adhesive strips offer an alternative method to close the epidermal layer. The aim of this study was to compare adhesive strip closure with absorbable sutures for collar incisions in a prospective, single-blinded, randomized controlled trial.

Bidirectional Barbed Sutures for Wound Closure: Evolution and Applications

Science.gov (United States)

Paul, Malcolm D.

2009-01-01

Traditionally, wound closure sutures have in common the need to tie knots with the inherent risk of extrusion, palpability, microinfarcts, breakage, and slippage. Bidirectional barbed sutures have barbs arrayed in a helical fashion in opposing directions on either side of an unbarbed midsegment. This suture is inserted at the midpoint of a wound and pulled through till resistance is encountered from the opposing barbs; each half of the suture is then advanced to the lateral ends of the wound. This design provides a method of evenly distributing tension along the incision line, a faster suture placement and closure time with no need to tie knots, and the possibility of improved cosmesis. Bidirectional barbed sutures, which are available in both absorbable and nonabsorbable forms, can be used for simple closures, multilayered closures, and closure of high-tension wounds in a variety of surgical settings. PMID:24527114

Immobilisation of barley aleurone layers enables parallelisation of assays and analysis of transient gene expression in single cells

DEFF Research Database (Denmark)

Zor, Kinga; Mark, Christina; Heiskanen, Arto

2017-01-01

at a single time point. By immobilising barley aleurone layer tissue on polydimethylsiloxane pillars in the lid of a multiwell plate, continuous monitoring of living tissue is enabled using multiple non-destructive assays in parallel. Cell viability and menadione reducing capacity were monitored in the same...

Raman spectroscopy of boron-doped single-layer graphene.

Science.gov (United States)

Kim, Yoong Ahm; Fujisawa, Kazunori; Muramatsu, Hiroyuki; Hayashi, Takuya; Endo, Morinobu; Fujimori, Toshihiko; Kaneko, Katsumi; Terrones, Mauricio; Behrends, Jan; Eckmann, Axel; Casiraghi, Cinzia; Novoselov, Kostya S; Saito, Riichiro; Dresselhaus, Mildred S

2012-07-24

The introduction of foreign atoms, such as nitrogen, into the hexagonal network of an sp(2)-hybridized carbon atom monolayer has been demonstrated and constitutes an effective tool for tailoring the intrinsic properties of graphene. Here, we report that boron atoms can be efficiently substituted for carbon in graphene. Single-layer graphene substitutionally doped with boron was prepared by the mechanical exfoliation of boron-doped graphite. X-ray photoelectron spectroscopy demonstrated that the amount of substitutional boron in graphite was ~0.22 atom %. Raman spectroscopy demonstrated that the boron atoms were spaced 4.76 nm apart in single-layer graphene. The 7-fold higher intensity of the D-band when compared to the G-band was explained by the elastically scattered photoexcited electrons by boron atoms before emitting a phonon. The frequency of the G-band in single-layer substitutionally boron-doped graphene was unchanged, which could be explained by the p-type boron doping (stiffening) counteracting the tensile strain effect of the larger carbon-boron bond length (softening). Boron-doped graphene appears to be a useful tool for engineering the physical and chemical properties of graphene.

Endoscopic suture fixation is associated with reduced migration of esophageal fully covered self-expandable metal stents (FCSEMS).

Science.gov (United States)

Wright, Andrew; Chang, Andrew; Bedi, Aarti Oza; Wamsteker, Erik-Jan; Elta, Grace; Kwon, Richard S; Carrott, Phillip; Elmunzer, B Joseph; Law, Ryan

2017-09-01

Esophageal fully covered self-expandable metal stents (FCSEMS) are indicated for the management of benign and malignant conditions of the esophagus including perforations, leaks, and strictures. FCSEMS are resistant to tissue ingrowth and are removable; however, stent migration occurs in 30-55% of cases. Endoscopic suture fixation of FCSEMS has been utilized to decrease the risk of stent migration though data supporting this practice remain limited. The primary aim of this study was to compare clinical outcomes and migration rate of patients who underwent placement of esophageal FCSEMS with and without endoscopic suture fixation. Our single-center, retrospective, cohort study includes patients who underwent esophageal FCSEMS placement with and without endoscopic suture fixation between January 1, 2012, and November 11, 2015. Baseline patient characteristics, procedural details, and clinical outcomes were abstracted. Logistic regression was performed to identify clinical and technical factors associated with outcomes and stent migration. A total of 51 patients underwent 62 FCSEMS placements, including 21 procedures with endoscopic suture fixation and 41 without. Suture fixation was associated with reduced risk of stent migration (OR 0.13, 95% CI 0.03-0.47). Prior stent migration was associated with significantly higher risk of subsequent migration (OR 6.4, 95% CI 1.6-26.0). Stent migration was associated with lower likelihood of clinical success (OR 0.21, 95% CI 0.06-0.69). There was a trend toward higher clinical success among patients undergoing suture fixation (85.7 vs. 60.9%, p = 0.07). Endoscopic suture fixation of FCSEMS was associated with a reduced stent migration rate. Appropriate patient selection for suture fixation of FCSEMS may lead to reduced migration in high-risk patients.

A technique for introducing looped sutures in flexor tendon repair

Directory of Open Access Journals (Sweden)

Kamath B

2006-01-01

Full Text Available Stronger flexor tendon repairs facilitate early active motion therapy protocols. Core sutures using looped suture material provide 1 ½ to twice the strength of Kessler′s technique (with four strand and six strand Tsuge technique respectively. The technique is well-described and uses preformed looped sutures (supramid. This is not available in many countries and we describe a technique whereby looped sutures can be introduced in flexor tendon repair by the use of 23 G hypodermic needle and conventional 4.0 or 5.0 sutures. This is an alternative when the custom made preformed sutures are not available. This can be practiced in zone 3 to zone 5 repairs. Technical difficulties limit its use in zone 2 repairs.

Single-layer ZnMN2 (M = Si, Ge, Sn) zinc nitrides as promising photocatalysts.

Science.gov (United States)

Bai, Yujie; Luo, Gaixia; Meng, Lijuan; Zhang, Qinfang; Xu, Ning; Zhang, Haiyang; Wu, Xiuqiang; Kong, Fanjie; Wang, Baolin

2018-05-30

Searching for two-dimensional semiconductor materials that are suitable for visible-light photocatalytic water splitting provides a sustainable solution to deal with the future energy crisis and environmental problems. Herein, based on first-principles calculations, single-layer ZnMN2 (M = Si, Ge, Sn) zinc nitrides are proposed as efficient photocatalysts for water splitting. Stability analyses show that the single-layer ZnMN2 zinc nitrides exhibit energetic and dynamical stability. The electronic properties reveal that all of the single-layer ZnMN2 zinc nitrides are semiconductors. Interestingly, single-layer ZnSnN2 is a direct band gap semiconductor with a desirable band gap (1.74 eV), and the optical adsorption spectrum confirms its optical absorption in the visible light region. The hydrogen evolution reaction (HER) calculations show that the catalytic activity for single-layer ZnMN2 (M = Ge, Sn) is better than that of single-layer ZnSiN2. Furthermore, the band gaps and band edge positions for the single-layer ZnMN2 zinc nitrides can be effectively tuned by biaxial strain. Especially, single-layer ZnGeN2 can be effectively tuned to match better with the redox potentials of water and enhance the light absorption in the visible light region at a tensile strain of 5%, which is confirmed by the corresponding optical absorption spectrum. Our results provide guidance for experimental synthesis efforts and future searches for single-layer materials suitable for photocatalytic water splitting.

Synthesis of PbI(2) single-layered inorganic nanotubes encapsulated within carbon nanotubes.

Science.gov (United States)

Cabana, Laura; Ballesteros, Belén; Batista, Eudar; Magén, César; Arenal, Raúl; Oró-Solé, Judith; Rurali, Riccardo; Tobias, Gerard

2014-04-02

The template assisted growth of single-layered inorganic nanotubes is reported. Single-crystalline lead iodide single-layered nanotubes have been prepared using the inner cavities of carbon nanotubes as hosting templates. The diameter of the resulting inorganic nanotubes is merely dependent on the diameter of the host. This facile method is highly versatile opening up new horizons in the preparation of single-layered nanostructures. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Penetration of a Small Caliber Projectile into Single and Multi-layered Targets

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Riad A.M.

2010-06-01

Full Text Available The normal penetration of armor-piercing projectiles into single and multi-layered steel plates has been investigated. An experimental program has been conducted to study the effect of spaced and in-contact layered targets on their ballistic resistance. Armor piercing projectiles with caliber of 7.62 mm were fired against a series of single and multi-layered steel targets. The projectile impact velocities were ranged from 300-600 m/s, whereas the total thicknesses of the tested single, spaced and in-contact layered steel targets were 3 mm. The penetration process of different tested target configurations has been simulated using Autodayn-2D hydrocode. The experimental measurements of the present work were used to discuss the effect of impact velocity, target configurations and number of layers of different spaced and in-contact layered steel targets on their ballistic resistance. In addition, the post-firing examination of the tested targets over the used impact velocity range showed that the single and each layer of spaced and in-contact laminated steel targets were failed by petalling. Finally, the obtained experimental measurements were compared with the corresponding numerical results of Autodyn-2D hydrocode, good agreement was generally obtained.

Microvascular anastomoses in irradiated vessels: A comparison between the Unilink system and sutures

International Nuclear Information System (INIS)

Ragnarsson, R.; Berggren, A.; Klintenberg, C.; Ostrup, L.

1990-01-01

A new mechanical device (the Unilink system) was compared to conventional suture anastomoses in irradiated microvessels. Twenty rabbits received a single radiation dose of 20 Gy from a 7-MeV electron source through an anterior neck field. One and 6 months following irradiation, the carotid arteries and facial veins were divided and anastomosed on one side with the Unilink system and on the other side with suture technique. At sacrifice 4 weeks postoperatively, all vessels were evaluated for patency and histologic changes associated with radiation and anastomotic trauma. Histology disclosed severe radiation changes. Also, intimal hyperplasia was consistently found at the anastomotic sites in the arteries, while it was totally absent in the venous anastomoses. Occlusive thrombosis was found in two arteries, one anastomosed with the Unilink system and one sutured. Two other arteries, one from each group, had subtotal occlusions at the anastomotic site. No occlusions occurred in any of the venous anastomoses. The overall patency in this study was 97.5 percent, with no difference between the two techniques

Nano-soldering to single atomic layer

Science.gov (United States)

Girit, Caglar O [Berkeley, CA; Zettl, Alexander K [Kensington, CA

2011-10-11

A simple technique to solder submicron sized, ohmic contacts to nanostructures has been disclosed. The technique has several advantages over standard electron beam lithography methods, which are complex, costly, and can contaminate samples. To demonstrate the soldering technique graphene, a single atomic layer of carbon, has been contacted, and low- and high-field electronic transport properties have been measured.

Adjustable suture strabismus surgery in infants and children: a 19-year experience.

Science.gov (United States)

Kassem, Ahmed; Xue, Gilbert; Gandhi, Niral B; Tian, Jing; Guyton, David L

2018-06-01

To evaluate the success rate of adjustable suture techniques in horizontal eye muscle surgery in children ≤15 years of age over a 19-year period by a single surgeon. The medical records of all consecutive patients in this age group who underwent horizontal eye muscle surgery from 1989 through 2012 were reviewed retrospectively. Patients were divided into two groups: those in whom a nonadjustable suture technique was used and those in whom adjustable sutures were used. The following data were collected: type of strabismus, preoperative measurements, postoperative results, and reoperation rates. A total of 116 cases in the nonadjustable group and 521 cases in the adjustable group were included. In the adjustable group, adjustment was performed in 63% of the cases, because of either an under- (41%) or overcorrection (22%). The adjustment procedure was performed under topical proparacaine in 15% of cases and under intravenous propofol in 85%. For the adjustable group, 3-5 minutes more per muscle intraoperatively and 15-20 minutes for adjustment were required. No complications were encountered during the adjustment procedures. Early success rate, defined as alignment within 8 Δ of straight at 3 to 6 months' postoperative follow-up, was significantly greater in the adjustable group than in the nonadjustable group (77.7% vs 64.6% [P ≤ 0.03]). Of the adjustable patients, 15% required reoperation compared with 21% of the nonadjustable patients. Use of adjustable sutures in horizontal eye muscle surgery in children ≤15 years of age provided an improved success rate and fewer reoperations compared with nonadjustable sutures. Copyright © 2018 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

Comparison of suture types in the closure of scalp wounds.

LENUS (Irish Health Repository)

Bonham, Joseph

2011-06-01

Innovation in practice can benefit patients and healthcare providers but must be evidence based. This article describes a quantitative study of whether absorbable sutures are as beneficial as non-absorbable sutures in the management of simple scalp lacerations in adults. The results suggest that absorbable sutures can provide the same cosmetic and functional results as non-absorbable sutures. Their use can also reduce patient returns and save money and resources.

A comparison of lateral ankle ligament suture anchor strength.

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Barber, F Alan; Herbert, Morley A; Crates, John M

2013-06-01

Lateral ankle ligament repairs increasingly use suture anchors instead of bone tunnels. Our purpose was to compare the biomechanical properties of a knotted and knotless suture anchor appropriate for a lateral ankle ligament reconstruction. In porcine distal fibulae, 10 samples of 2 different PEEK anchors were inserted. The attached sutures were cyclically loaded between 10N and 60N for 200 cycles. A destructive pull was performed and failure loads, cyclic displacement, stiffness, and failure mode recorded. PushLock 2.5 anchors failed before 200 cycles. PushLock 100 cycle displacement was less than Morphix 2.5 displacement (panchors completing 200 cycles was 86.5N (PushLock) and 252.1N (Morphix) (panchor breaking and suture breakage. The knotted Morphix demonstrated more displacement and greater failure strength than the knotless PushLock. The PushLock failed consistently with suture breaking. The Morphix anchor failed both by anchor breaking and by suture breaking. Copyright © 2012 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

Bronchus anastomosis after sleeve resection for lung cancer: does the suture technique have an impact on postoperative complication rate?

Science.gov (United States)

Palade, Emanuel; Holdt, Holger; Passlick, Bernward

2015-06-01

Bronchoplastic resections emerged as an alternative to pneumonectomy for patients with impaired pulmonary function and have gained popularity due to a marked decrease in morbidity and at least similar oncological outcome. Actual guidelines recommend sleeve resections whenever technically feasible, even in cases with adequate pulmonary reserve for pneumonectomy, in order to maximally preserve functional lung parenchyma. Various suture techniques were described; the existing evidence, however, is insufficient to recommend one of them as standard. The aim of this study was to compare two suture techniques for bronchus repair after sleeve resection. Two groups of patients from two separate institutions were retrospectively analysed. In Group A (n = 20), the anastomosis was performed with a running suture at the membranous part and an interrupted suture for the rest of the circumference. In Group B (n = 40), a telescoping continuous suture was used. Intra- and postoperative findings directly related to the anastomosis were compared. The parameters were assessed as absolute numbers and percentages; the statistical significance was determined using Pearson's χ(2) test for categorical variables and Student's t-test for continuous data (P resection type (predominance of the right upper lobe for Group B), the groups were comparable regarding patient characteristics. The intraoperative anastomotic assessment revealed: patency 100% in both groups, initial air tightness (100 vs 82.5%; P = 0.047) and buttressing 85 vs 5%. No suture revision was necessary in both groups. The analysis of anastomosis-related morbidity revealed no significant difference: atelectasis (1 in Group A and 2 in Group B; P = 1), reversible anastomotic changes (0 vs 2; P = 0.309), early stenosis (0 vs 0), bronchopleural fistula (1 vs 0; P = 0.154), bronchovascular fistula (0 vs 0), late stenosis (1 vs 0; P = 0.119) and reoperations (15 vs 5%; P = 0.186). The operative mortality rate was similar (2 vs 3; P

Surgical sutures filled with adipose-derived stem cells promote wound healing.

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Ann Katharin Reckhenrich

Full Text Available Delayed wound healing and scar formation are among the most frequent complications after surgical interventions. Although biodegradable surgical sutures present an excellent drug delivery opportunity, their primary function is tissue fixation. Mesenchymal stem cells (MSC act as trophic mediators and are successful in activating biomaterials. Here biodegradable sutures were filled with adipose-derived mesenchymal stem cells (ASC to provide a pro-regenerative environment at the injured site. Results showed that after filling, ASCs attach to the suture material, distribute equally throughout the filaments, and remain viable in the suture. Among a broad panel of cytokines, cell-filled sutures constantly release vascular endothelial growth factor to supernatants. Such conditioned media was evaluated in an in vitro wound healing assay and showed a significant decrease in the open wound area compared to controls. After suturing in an ex vivo wound model, cells remained in the suture and maintained their metabolic activity. Furthermore, cell-filled sutures can be cryopreserved without losing their viability. This study presents an innovative approach to equip surgical sutures with pro-regenerative features and allows the treatment and fixation of wounds in one step, therefore representing a promising tool to promote wound healing after injury.

Anatomy-Based navigation for ventriculostomy: Nasion-coronal suture distance measurement

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Mevci Özdemir

2014-09-01

Full Text Available Objective: In this study we aimed to determine a landmark that can be measured through the skin with nasal mid-point (bregma to coronal suture, and additionally an average value was calculated. We report, to our knowledge, the distance between the nasion-coronal sutures is reported for the first time in Turkish population. Methods: The study included 30 craniums and 30 frontal bones. Each skull from midline nasal suture to coronal suture curved up at the distance was measured with tape measure. Results: Mean values were determined. Nasal suture between coronal suture distance average 12,2 cm (min10,3 cm, up to 13,5 cm were detected. Conclusion: Nasal suture is an easily palpable area through the skin. A small incision is carried down through skin to bone at the spot 12 cm back from the nasion 3 cm lateral to the midline for ventricular drainage operation. This data provide practical information for neurosurgeon and is available everywhere. J Clin Exp Invest 2014; 5 (3: 368-370

Density functional theory study of bulk and single-layer magnetic semiconductor CrPS4

Science.gov (United States)

Zhuang, Houlong L.; Zhou, Jia

2016-11-01

Searching for two-dimensional (2D) materials with multifunctionality is one of the main goals of current research in 2D materials. Magnetism and semiconducting are certainly two desirable functional properties for a single 2D material. In line with this goal, here we report a density functional theory (DFT) study of bulk and single-layer magnetic semiconductor CrPS4. We find that the ground-state magnetic structure of bulk CrPS4 exhibits the A-type antiferromagnetic ordering, which transforms to ferromagnetic (FM) ordering in single-layer CrPS4. The calculated formation energy and phonon spectrum confirm the stability of single-layer CrPS4. The band gaps of FM single-layer CrPS4 calculated with a hybrid density functional are within the visible-light range. We also study the effects of FM ordering on the optical absorption spectra and band alignments for water splitting, indicating that single-layer CrPS4 could be a potential photocatalyst. Our work opens up ample opportunities of energy-related applications of single-layer CrPS4.

Craniosynostosis of coronal suture in Twist1+/- mice occurs through endochondral ossification recapitulating the physiological closure of posterior frontal suture

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Bjorn eBehr

2011-07-01

Full Text Available Craniosynostosis, the premature closure of cranial suture, is a pathologic condition that affects 1/2000 live births. Saethre-Chotzen syndrome is a genetic condition characterized by craniosynostosis. The Saethre-Chotzen syndrome, which is defined by loss-of-function mutations in the TWIST gene, is the second most prevalent craniosynostosis. Although much of the genetics and phenotypes in craniosynostosis syndromes is understood, less is known about the underlying ossification mechanism during suture closure. We have previously demonstrated that physiological closure of the posterior frontal (PF suture occurs through endochondral ossification. Moreover, we revealed that antagonizing canonical Wnt signaling in the sagittal suture leads to endochondral ossification of the suture mesenchyme and sagittal synostosis, presumably by inhibiting Twist1. Classic Saethre-Chotzen syndrome is characterized by coronal synostosis, and the haploinsufficient Twist1+/- mice represents a suitable model for studying this syndrome. Thus, we seeked to understand the underlying ossification process in coronal craniosynostosis in Twist1+/- mice. Our data indicate that coronal suture closure in Twist1+/- mice occurs between postnatal day 9 to 13 by endochondral ossification, as shown by histology, gene expression analysis and immunohistochemistry. In conclusion, this study reveals that coronal craniosynostosis in Twist1+/- mice occurs through endochondral ossification. Moreover, it suggests that haploinsufficency of Twist1 gene, a target of canonical Wnt-signaling, and inhibitor of chondrogenesis, mimics conditions of inactive canonical Wnt-signaling leading to craniosynostosis.

Skull morphometry and vault sutures of Myrmecophaga tridactyla and Tamandua tetradactyla

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Camila M. de S. Hossotani

2017-10-01

Full Text Available ABSTRACT This study aimed to examine the relationship between skull size and the level of cranial vault suture closure. A total of 50 Myrmecophaga tridactyla Linnaeus, 1758 and 178 Tamandua tetradactyla Linnaeus, 1758 skulls were analyzed in relation to 18 skull dimensions. The skulls were grouped into three levels of suture closure: no sutures closed (level 0, one or all the fallowing sutures closed: interfrontalis, sagitalis and coronalis (level 1 and all sutures closed (level 2. The results indicated that among the 18 variables measured, 17 showed significant differences (p ≤ 0.01 between level 0 and level 1 skulls of T. tetradactyla; as well as between level 0 and level 1, and level 0 and level 2 skulls of M. tridactyla. M. tridactyla level 1 and level 2 had no significant difference among any of the 18 dimensions. The foramen magnum height in both species showed no significant difference (p > 0.05 among any suture categories. In principle, suture closure level and cranial dimensions are related. The specimens with larger cranial dimensions showed greater number of cranial vault sutures closed for both species of anteaters. Tamandua tetradactyla and M. tridactyla specimens with none of the cranial vault suture closed have a foramen magnum height similar to those with cranial vault suture closed.

Single-layer and dual-layer contrast-enhanced mammography using amorphous selenium flat panel detectors

Energy Technology Data Exchange (ETDEWEB)

Allec, N; Abbaszadeh, S; Karim, K S, E-mail: nallec@uwaterloo.ca [Department of Electrical and Computer Engineering, University of Waterloo, 200 University Avenue West, Waterloo N2L 3G1 (Canada)

2011-09-21

The accumulation of injected contrast agents allows the image enhancement of lesions through the use of contrast-enhanced mammography. In this technique, the combination of two acquired images is used to create an enhanced image. There exist several methods to acquire the images to be combined, which include dual energy subtraction using a single detection layer that suffers from motion artifacts due to patient motion between image acquisition. To mitigate motion artifacts, a detector composed of two layers may be used to simultaneously acquire the low and high energy images. In this work, we evaluate both of these methods using amorphous selenium as the detection material to find the system parameters (tube voltage, filtration, photoconductor thickness and relative intensity ratio) leading to the optimal performance. We then compare the performance of the two detectors under the variation of contrast agent concentration, tumor size and dose. The detectability was found to be most comparable at the lower end of the evaluated factors. The single-layer detector not only led to better contrast, due to its greater spectral separation capabilities, but also had lower quantum noise. The single-layer detector was found to have a greater detectability by a factor of 2.4 for a 2.5 mm radius tumor having a contrast agent concentration of 1.5 mg ml{sup -1} in a 4.5 cm thick 50% glandular breast. The inclusion of motion artifacts in the comparison is part of ongoing research efforts.

Single-layer and dual-layer contrast-enhanced mammography using amorphous selenium flat panel detectors

Science.gov (United States)

Allec, N.; Abbaszadeh, S.; Karim, K. S.

2011-09-01

The accumulation of injected contrast agents allows the image enhancement of lesions through the use of contrast-enhanced mammography. In this technique, the combination of two acquired images is used to create an enhanced image. There exist several methods to acquire the images to be combined, which include dual energy subtraction using a single detection layer that suffers from motion artifacts due to patient motion between image acquisition. To mitigate motion artifacts, a detector composed of two layers may be used to simultaneously acquire the low and high energy images. In this work, we evaluate both of these methods using amorphous selenium as the detection material to find the system parameters (tube voltage, filtration, photoconductor thickness and relative intensity ratio) leading to the optimal performance. We then compare the performance of the two detectors under the variation of contrast agent concentration, tumor size and dose. The detectability was found to be most comparable at the lower end of the evaluated factors. The single-layer detector not only led to better contrast, due to its greater spectral separation capabilities, but also had lower quantum noise. The single-layer detector was found to have a greater detectability by a factor of 2.4 for a 2.5 mm radius tumor having a contrast agent concentration of 1.5 mg ml-1 in a 4.5 cm thick 50% glandular breast. The inclusion of motion artifacts in the comparison is part of ongoing research efforts.

A randomized study comparing outcomes of stapled and hand-sutured anastomoses in patients undergoing open gastrointestinal surgery.

Science.gov (United States)

Chandramohan, S M; Gajbhiye, Raj Narenda; Agwarwal, Anil; Creedon, Erin; Schwiers, Michael L; Waggoner, Jason R; Tatla, Daljit

2013-08-01

Although stapling is an alternative to hand-suturing in gastrointestinal surgery, recent trials specifically designed to evaluate differences between the two in surgery time, anastomosis time, and return to bowel activity are lacking. This trial compared the outcomes of the two in subjects undergoing open gastrointestinal surgery. Adult subjects undergoing emergency or elective surgery requiring a single gastric, small, or large bowel anastomosis were enrolled into this open-label, prospective, randomized, interventional, parallel, multicenter, controlled trial. Randomization was assigned in a 1:1 ratio between the hand-sutured group (n = 138) and the stapled group (n = 142). Anastomosis time, surgery time, and time to bowel activity were collected and compared as primary endpoints. A total of 280 subjects were enrolled from April 2009 to September 2010. Only the time of anastomosis was significantly different between the two arms: 17.6 ± 1.90 min (stapled) and 20.6 ± 1.90 min (hand-sutured). This difference was deemed not clinically or economically meaningful. Safety outcomes and other secondary endpoints were similar between the two arms. Mechanical stapling is faster than hand-suturing for the construction of gastrointestinal anastomoses. Apart from this, stapling and hand-suturing are similar with respect to the outcomes measured in this trial.

Single versus double row suture anchor fixation for greater tuberosity fractures - a biomechanical study.

Science.gov (United States)

Seppel, Gernot; Saier, Tim; Martetschläger, Frank; Plath, Johannes E; Guevara-Alvarez, Alberto; Henschel, Julia; Winkler, Martin; Augat, Peter; Imhoff, Andreas B; Buchmann, Stefan

2017-12-01

Fractures of the humeral greater tuberosity (GT) are a frequent injury progressively treated with arthroscopic suture anchor repair. Yet, no biomechanical study has been performed comparing fixation strength of arthroscopic single- (SR) vs. double row (DR) fixation. Standardized fractures of the greater tuberosity were created in 12 fresh frozen proximal humeri. After random assignation to the SR or DR group the fixed humeri were tested applying cyclic loading to the supraspinatus and infraspinatus tendon. Load to failure and fragment displacement were assessed by means of an electrodynamic material testing machine using an optical tracking system. Load to failure values were higher in the DR group (649 N; ±176) than in the SR group (490 N; ±145) however without statistical significance (p = .12). In greater tuberosity displacement of 3-5 mm surgical treatment is recommended. The fixing constructs in this study did not reach displacement landmarks of 3 or 5 mm before construct failure as shown in previous studies. Thus the applied traction force (N) at 1 mm displacement was analyzed. In the SR group the load at 1 mm displacement was 277 N; ±46 compared to 260 N; ±62 in the DR group (p = .65). The results suggest that both techniques are viable options for refixation of greater tuberosity fractures. Laboratory study.

Biomechanical comparison of an all-soft suture anchor with a modified Broström-Gould suture repair for lateral ligament reconstruction.

Science.gov (United States)

Brown, Christopher A; Hurwit, Daniel; Behn, Anthony; Hunt, Kenneth J

2014-02-01

Anatomic repair is indicated for patients who have recurrent lateral ankle instability despite nonoperative measures. There is no difference in repair stiffness, failure torque, or failure angle between specimens repaired with all-soft suture anchors versus the modified Broström-Gould technique with sutures only. Controlled laboratory study. In 10 matched pairs of human cadaveric ankles, the anterior talofibular ligament (ATFL) was incised from its origin on the fibula. After randomization, 1 ankle was repaired to its anatomic insertion using two 1.4-mm JuggerKnot all-soft suture anchors; the other ankle was repaired with a modified Broström-Gould technique using 2-0 FiberWire. All were augmented using the inferior extensor retinaculum. All ankles were mounted to the testing machine in 20° of plantar flexion and 15° of internal rotation and loaded to failure after the repair. Stiffness, failure torque, and failure angle were recorded and compared using a paired Student t test with a significance level set at P anchors pulled out of bone. The primary mode of failure was pulling through the ATFL tissue. There was no statistical difference in strength or stiffness between a 1.4-mm all-soft suture anchor and a modified Broström-Gould repair with 2-0 FiberWire. The primary mode of failure was at the tissue level rather than knot failure or anchor pullout. The particular implant choice (suture only, tunnel, anchor) in repairing the lateral ligament complex may not be as important as the time to biological healing. The suture-only construct as described in the Broström-Gould repair was as strong as all-soft suture anchors, and the majority of the ankles failed at the tissue level. For those surgeons whose preference is to use anchor repair, this novel all-soft suture anchor may be an alternative to other larger anchors, as none failed by pullout.

Viable adhered Staphylococcus aureus highly reduced on novel antimicrobial sutures using chlorhexidine and octenidine to avoid surgical site infection (SSI)

Science.gov (United States)

Schneider, Jochen; Harrasser, Norbert; Tübel, Jutta; Mühlhofer, Heinrich; Pförringer, Dominik; von Deimling, Constantin; Foehr, Peter; Kiefel, Barbara; Krämer, Christina; Stemberger, Axel; Schieker, Matthias

2018-01-01

Background Surgical sutures can promote migration of bacteria and thus start infections. Antiseptic coating of sutures may inhibit proliferation of adhered bacteria and avoid such complications. Objectives This study investigated the inhibition of viable adhering bacteria on novel antimicrobially coated surgical sutures using chlorhexidine or octenidine, a critical factor for proliferation at the onset of local infections. The medical need, a rapid eradication of bacteria in wounds, can be fulfilled by a high antimicrobial efficacy during the first days after wound closure. Methods As a pretesting on antibacterial efficacy against relevant bacterial pathogens a zone of inhibition assay was conducted with middle ranged concentrated suture coatings (22 μg/cm). For further investigation of adhering bacteria in detail the most clinically relevant Staphylococcus aureus (ATCC®49230™) was used. Absorbable braided sutures were coated with chlorhexidine-laurate, chlorhexidine-palmitate, octenidine-laurate, and octenidine-palmitate. Each coating type resulted in 11, 22, or 33 μg/cm drug content on sutures. Scanning electron microscopy (SEM) was performed once to inspect the coating quality and twice to investigate if bacteria have colonized on sutures. Adhesion experiments were assessed by exposing coated sutures to S. aureus suspensions for 3 h at 37°C. Subsequently, sutures were sonicated and the number of viable bacteria released from the suture surface was determined. Furthermore, the number of viable planktonic bacteria was measured in suspensions containing antimicrobial sutures. Commercially available sutures without drugs (Vicryl®, PGA Resorba®, and Gunze PGA), as well as triclosan-containing Vicryl® Plus were used as control groups. Results Zone of inhibition assay documented a multispecies efficacy of novel coated sutures against tested bacterial strains, comparable to most relevant S. aureus over 48 hours. SEM pictures demonstrated uniform layers on

Magnetic moment of single layer graphene rings

Science.gov (United States)

Margulis, V. A.; Karpunin, V. V.; Mironova, K. I.

2018-01-01

Magnetic moment of single layer graphene rings is investigated. An analytical expression for the magnetic moment as a function of the magnetic field flux through the one-dimensional quantum rings is obtained. This expression has the oscillation character. The oscillation period is equal to one flux quanta.

The frontosphenoidal suture: fetal development and phenotype of its synostosis

Energy Technology Data Exchange (ETDEWEB)

Mathijssen, Irene M.J.; Meulen, Jacques J.N.M. van der; Adrichem, Leon N.A. van; Vaandrager, J.M.; Vermeij-Keers, Christl [Erasmus MC, University Medical Centre, Department of Plastic and Reconstructive Surgery, Rotterdam (Netherlands); Hulst, Rene R.W.J. van der [University Hospital Maastricht, Department of Plastic and Reconstructive Surgery, Maastricht (Netherlands); Lequin, Maarten H. [Erasmus MC, University Medical Centre, Department of Radiology, Rotterdam (Netherlands)

2008-04-15

Isolated synostosis of the frontosphenoidal suture is very rare and difficult to diagnose. Little has been reported on the clinical presentation and fetal development of this suture. To understand the development of the frontosphenoidal suture and the outcome of its synostosis. We studied the normal fetal development of the frontosphenoidal suture in dry human skulls and the clinical features of four patients with isolated synostosis of the frontosphenoidal suture. The frontosphenoidal suture develops relatively late during the second trimester of pregnancy, which explains the mild phenotype when there is synostosis. This rare craniosynostosis results in a deformity that causes recession of the lateral part of the frontal bone and supraorbital rim, with minimal facial asymmetry. Three-dimensional CT is the best examination to confirm the diagnosis. Isolated frontosphenoidal synostosis should be considered in patients with unilateral flattening of the forehead at birth that does not improve within the first few months of life. (orig.)

Chemical and morphological modifications of single layer graphene submitted to annealing in water vapor

Science.gov (United States)

Rolim, Guilherme Koszeniewski; Corrêa, Silma Alberton; Galves, Lauren Aranha; Lopes, João Marcelo J.; Soares, Gabriel Vieira; Radtke, Cláudio

2018-01-01

Modifications of single layer graphene transferred to SiO2/Si substrates resulting from annealing in water vapor were investigated. Near edge X-ray absorption fine structure spectroscopy evidenced graphene puckering between 400 and 500 °C. Synchrotron radiation based X-ray photoelectron spectroscopy showed variation of sp2 and sp3C bonding configurations specially in this same temperature range. Moreover, oxygen related functionalities are formed as a result of water vapor annealing. Based on these results and complementary Raman and nuclear reaction analysis, one distinguishes three different regimes of water interaction with graphene concerning modifications of the graphene layer. In the low temperature range (200-400 °C), no prominent modification of graphene itself is observed. At higher temperatures (400-500 °C), to accommodate newly formed oxygen functionalities, the flat and continuous sp2 bonding network of graphene is disrupted, giving rise to a puckered layer. For 600 °C and above, shrinking of graphene domains and a higher doping level take place.

Hemodynamic monitoring in different cortical layers with a single fiber optical system

Science.gov (United States)

Yu, Linhui; Noor, M. Sohail; Kiss, Zelma H. T.; Murari, Kartikeya

2018-02-01

Functional monitoring of highly-localized deep brain structures is of great interest. However, due to light scattering, optical methods have limited depth penetration or can only measure from a large volume. In this research, we demonstrate continuous measurement of hemodynamics in different cortical layers in response to thalamic deep brain stimulation (DBS) using a single fiber optical system. A 200-μm-core-diameter multimode fiber is used to deliver and collect light from tissue. The fiber probe can be stereotaxically implanted into the brain region of interest at any depth to measure the di use reflectance spectra from a tissue volume of 0.02-0.03 mm3 near the fiber tip. Oxygenation is then extracted from the reflectance spectra using an algorithm based on Monte Carlo simulations. Measurements were performed on the surface (cortical layer I) and at 1.5 mm depth (cortical layer VI) of the motor cortex in anesthetized rats with thalamic DBS. Preliminary results revealed the oxygenation changes in response to DBS. Moreover, the baseline as well as the stimulus-evoked change in oxygenation were different at the two depths of cortex.

The continuous structure bending of the three-layer plate with the lightweight aggregate

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Zhuravlev Alexander

2017-01-01

Full Text Available This paper deals with the problem of finding the effective way to solve the task of the composite construction bending of the three-layer plate with the lightweight aggregate, which operates on a continuous pattern. The expressions for the parameters determination, regarding a reduction of support bending moments due to the shear deformation of the middle layer, are given. The three-membered structure equation, connecting three bending moments, occurring above three adjacent pillars of the continuous three-layer beam, is obtained based on the condition of the movement compatibility.

Learning rate and attractor size of the single-layer perceptron

International Nuclear Information System (INIS)

Singleton, Martin S.; Huebler, Alfred W.

2007-01-01

We study the simplest possible order one single-layer perceptron with two inputs, using the delta rule with online learning, in order to derive closed form expressions for the mean convergence rates. We investigate the rate of convergence in weight space of the weight vectors corresponding to each of the 14 out of 16 linearly separable rules. These vectors follow zigzagging lines through the piecewise constant vector field to their respective attractors. Based on our studies, we conclude that a single-layer perceptron with N inputs will converge in an average number of steps given by an Nth order polynomial in (t/l), where t is the threshold, and l is the size of the initial weight distribution. Exact values for these averages are provided for the five linearly separable classes with N=2. We also demonstrate that the learning rate is determined by the attractor size, and that the attractors of a single-layer perceptron with N inputs partition R N +R N

Thermal vibration of a rectangular single-layered graphene sheet with quantum effects

International Nuclear Information System (INIS)

Wang, Lifeng; Hu, Haiyan

2014-01-01

The thermal vibration of a rectangular single-layered graphene sheet is investigated by using a rectangular nonlocal elastic plate model with quantum effects taken into account when the law of energy equipartition is unreliable. The relation between the temperature and the Root of Mean Squared (RMS) amplitude of vibration at any point of the rectangular single-layered graphene sheet in simply supported case is derived first from the rectangular nonlocal elastic plate model with the strain gradient of the second order taken into consideration so as to characterize the effect of microstructure of the graphene sheet. Then, the RMS amplitude of thermal vibration of a rectangular single-layered graphene sheet simply supported on an elastic foundation is derived. The study shows that the RMS amplitude of the rectangular single-layered graphene sheet predicted from the quantum theory is lower than that predicted from the law of energy equipartition. The maximal relative difference of RMS amplitude of thermal vibration appears at the sheet corners. The microstructure of the graphene sheet has a little effect on the thermal vibrations of lower modes, but exhibits an obvious effect on the thermal vibrations of higher modes. The quantum effect is more important for the thermal vibration of higher modes in the case of smaller sides and lower temperature. The relative difference of maximal RMS amplitude of thermal vibration of a rectangular single-layered graphene sheet decreases monotonically with an increase of temperature. The absolute difference of maximal RMS amplitude of thermal vibration of a rectangular single-layered graphene sheet increases slowly with the rising of Winkler foundation modulus.

Induction Based Training leads to Highly Significant Improvements of Objective and Subjective Suturing Ability in Junior Doctors

Directory of Open Access Journals (Sweden)

Kevin Garry

2018-03-01

Full Text Available Background: Simulation based training has shown to be of benefit in the education of medical students. However, the impact of induction based clinical simulation on surgical ability of qualified doctors remains unclear.The aim of this study was to establish if a 60 minute teaching session integrated into an Emergency Medicine speciality induction program produces statistically significant improvements in objective and subjective suturing abilities of junior doctors commencing an Emergency Medicine rotation.Methods: The objective suturing abilities of 16 Foundation Year Two doctors were analysed using a validated OSATs scale prior to a novel teaching intervention. The doctors then undertook an intensive hour long workshop receiving one to one feedback before undergoing repeat OSATs assessment.Subjective ability was measured using a 5 point likert scale and self-assessed competency reporting interrupted suturing before and after the intervention. Photographs of wound closure before and after the intervention were recorded for further blinded assessment of impact of intervention. A survey regarding continued ability was repeated at four months following the intervention. The study took place on 7/12/16 during the Belfast Health and Social Care Trust Emergency Medicine induction in the Royal Victoria Hospital Belfast. The hospital is a regional level 1 trauma centre that has annual departmental attendances in excess of 200,000.All new junior doctors commencing the Emergency Medicine rotation were invited to partake in the study. All 16 agreed. The group consisted of a mixture of undergraduate and postgraduate medicaldoctors who all had 16 months experience working in a variety of medical or surgical jobs previously.Results: Following the teaching intervention objective and subjective abilities in interrupted suturing showed statistically significant improvement (P>0.005. Self-reporting of competency of independently suturingwounds improved from 50

Effect of the use of carprofen in dogs undergoing intense rehabilitation after lateral fabellar suture stabilization.

Science.gov (United States)

Gordon-Evans, Wanda J; Dunning, Diane; Johnson, Ann L; Knap, Kim E

2011-07-01

To determine whether carprofen, a commercially available NSAID, would decrease perceived exertion and signs of pain in dogs and therefore increase muscle mass and hind limb function without decreasing range of motion after lateral fabellar suture stabilization. Randomized, blinded, controlled clinical trial. 35 dogs with cranial cruciate ligament rupture and lateral fabellar suture stabilization followed by rehabilitation. All dogs underwent surgical stabilization of cranial cruciate ligament rupture by placement of a lateral fabellar suture. Dogs received carprofen (2.2 mg/kg [1 mg/lb], PO, q 12 h) for the first 7 days after surgery and underwent concentrated rehabilitation exercises during weeks 3, 5, and 7 after surgery. Eighteen dogs also received carprofen (2.2 mg/kg, PO, q 12 h) during the weeks of concentrated rehabilitation. Outcomes were measured by a single investigator, who was blinded to group assignments, using pressure platform gait analysis, goniometry, thigh circumference, and mean workout speed at a consistent level of exertion. There were no differences between the 2 groups in ground reaction forces, thigh circumference, or exertion (mean workout speed) over time or at any individual time point. However, both groups improved significantly over time for all outcome measures. Providing carprofen to dogs during concentrated rehabilitation after lateral fabellar suture stabilization did not improve hind limb function, range of motion, or thigh circumference, nor did it decrease perceived exertion, compared with control dogs. Carprofen was not a compulsory component of a physical therapy regimen after lateral fabellar suture stabilization.

Laser tissue welding in genitourinary reconstructive surgery: assessment of optimal suture materials.

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Poppas, D P; Klioze, S D; Uzzo, R G; Schlossberg, S M

1995-02-01

Laser tissue welding in genitourinary reconstructive surgery has been shown in animal models to decrease operative time, improve healing, and decrease postoperative fistula formation when compared with conventional suture controls. Although the absence of suture material is the ultimate goal, this has not been shown to be practical with current technology for larger repairs. Therefore, suture-assisted laser tissue welding will likely be performed. This study sought to determine the optimal suture to be used during laser welding. The integrity of various organic and synthetic sutures exposed to laser irradiation were analyzed. Sutures studied included gut, clear Vicryl, clear polydioxanone suture (PDS), and violet PDS. Sutures were irradiated with a potassium titanyl phosphate (KTP)-532 laser or an 808-nm diode laser with and without the addition of a light-absorbing chromophore (fluorescein or indocyanine green, respectively). A remote temperature-sensing device obtained real-time surface temperatures during lasing. The average temperature, time, and total energy at break point were recorded. Overall, gut suture achieved significantly higher temperatures and withstood higher average energy delivery at break point with both the KTP-532 and the 808-nm diode lasers compared with all other groups (P welding appears to be between 60 degrees and 80 degrees C. Gut suture offers the greatest margin of error for KTP and 808-nm diode laser welding with or without the use of a chromophore.

Shyok Suture Zone, N Pakistan: late Mesozoic Tertiary evolution of a critical suture separating the oceanic Ladakh Arc from the Asian continental margin

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Robertson, Alastair H. F.; Collins, Alan S.

2002-02-01

The Shyok Suture Zone (Northern Suture) of North Pakistan is an important Cretaceous-Tertiary suture separating the Asian continent (Karakoram) from the Cretaceous Kohistan-Ladakh oceanic arc to the south. In previously published interpretations, the Shyok Suture Zone marks either the site of subduction of a wide Tethyan ocean, or represents an Early Cretaceous intra-continental marginal basin along the southern margin of Asia. To shed light on alternative hypotheses, a sedimentological, structural and igneous geochemical study was made of a well-exposed traverse in North Pakistan, in the Skardu area (Baltistan). To the south of the Shyok Suture Zone in this area is the Ladakh Arc and its Late Cretaceous, mainly volcanogenic, sedimentary cover (Burje-La Formation). The Shyok Suture Zone extends northwards (ca. 30 km) to the late Tertiary Main Karakoram Thrust that transported Asian, mainly high-grade metamorphic rocks southwards over the suture zone. The Shyok Suture Zone is dominated by four contrasting units separated by thrusts, as follows: (1). The lowermost, Askore amphibolite, is mainly amphibolite facies meta-basites and turbiditic meta-sediments interpreted as early marginal basin rift products, or trapped Tethyan oceanic crust, metamorphosed during later arc rifting. (2). The overlying Pakora Formation is a very thick (ca. 7 km in outcrop) succession of greenschist facies volcaniclastic sandstones, redeposited limestones and subordinate basaltic-andesitic extrusives and flow breccias of at least partly Early Cretaceous age. The Pakora Formation lacks terrigenous continental detritus and is interpreted as a proximal base-of-slope apron related to rifting of the oceanic Ladakh Arc; (3). The Tectonic Melange (ocean ridge-type volcanics and recrystallised radiolarian cherts, interpreted as accreted oceanic crust. (4). The Bauma-Harel Group (structurally highest) is a thick succession (several km) of Ordovician and Carboniferous to Permian-Triassic, low

The roles of wetting liquid in the transfer process of single layer graphene onto arbitrary substrates.

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Kim, Ju Hun; Yi, Junghwa; Jin, Hyeong Ki; Kim, Un Jeong; Park, Wanjun

2013-11-01

Wet transfer is crucial for most device structures of the proposed applications employing single layer graphene in order to take advantage of the unique physical, chemical, bio-chemical and electrical properties of the graphene. However, transfer methodologies that can be used to obtain continuous film without voids, wrinkles and cracks are limited although film perfectness critically depends on the relative surface tension of wetting liquids on the substrate. We report the importance of wetting liquid in the transfer process with a systematic study on the parameters governing film integrity in single layer graphene grown via chemical vapor deposition. Two different suspension liquids (in terms of polar character) are tested for adequacy of transfer onto SiO2 and hexamethyldisiloxane (HMDS). We found that the relative surface tension of the wetting liquid on the surfaces of the substrate is related to transfer quality. In addition, dimethyl sulfoxide (DMSO) is introduced as a good suspension liquid to HMDS, a mechanically flexible substrate.

[Suture simulator - Cleft palate surgery].

Science.gov (United States)

Devinck, F; Riot, S; Qassemyar, A; Belkhou, A; Wolber, A; Martinot Duquennoy, V; Guerreschi, P

2017-04-01

Cleft palate requires surgery in the first years of life, furthermore repairing anatomically the soft and hard palate is complex on a surgical level because of the fine tissues and the local intraoral configuration. It is valuable to train first on simulators before going to the operating room. However, there is no material dedicated to learning how to perform intraoral sutures in cleft palate surgery. We made one, in an artisanal manner, in order to practice before the real surgical gesture. The simulator was designed based on precise anatomical data. A steel pipe, fixed on a rigid base represented the oral cavity. An adapted split spoon represented the palate. All pieces could be removed in order to apply a hydrocellular dressing before training for sutures. Our simulator was tested by 3 senior surgeons in our department in close to real-life conditions in order to evaluate its anatomical accuracy. It is valuable to have a simulator to train on cleft palate sutures within teaching university hospitals that manage this pathology. Our simulator has a very low cost, it is easy to make and is anatomically accurate. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Randomized clinical trial comparing manual suture and different models of mechanical suture in the mimicking of bariatric surgery in swine

Directory of Open Access Journals (Sweden)

Fernandes MA

2014-02-01

Full Text Available Marcos AP Fernandes,1 Bruno MT Pereira,2 Sandra M Guimarães,1 Aline Paganelli,3 Carlos Manoel CT Pereira,1 Claudio Sergio Batista4 1Institute of Obesity and Advanced Video Laparoscopic Surgery of Petropolis, Rio de Janeiro, Brazil; 2Division of Trauma, University of Campinas, São Paulo, Brazil; 3Laboratório de Patologia Micron Cell Diagnóstico, Rio de Janeiro, Brazil; 4Department of Gynecology and Obstetrics, Faculty of Medicine of Petropolis, Rio de Janeiro, Brazil Context and objective: Variations in the ability of surgeons served as motivation for the development of devices that, overcoming individual differences, allow the techniques to be properly performed, and of which the end result was the best possible. Every technique must be reproduced reliably by the majority of surgeons for their results to be adopted and recognized as effective. The aim of this study was to compare the results, from the point of view of anatomic pathology, of manual sutures versus mechanical sutures using different models of linear mechanical staplers, in the procedure of gastroenteroanastomosis and enteroanastomosis in swine. Methods: Thirty-six healthy, adult, male Sus scrofa domesticus pigs, weighing between 20.7 and 25.5 kg, were used. The swine were randomly divided into four groups of nine pigs, according to the type of suture employed: group A, manual suture with Polysorb® 3-0 wire; group B, 80-shear linear stapler (Covidien® Gia 8038-S; group C, 75-shear linear stapler (Ethicon® Tlc 75; and group D, 75-shear linear stapler (Resource® Yq 75-3. A temporal study was established on the seventh postoperative day for histopathological analysis, and the degree of inflammation, fibrosis, and newly formed vessels, as well as the presence or absence of granulation tissue, foreign body granuloma, and necrosis were all evaluated qualitatively and semiquantitatively. The results were analyzed statistically. Results: Observations during the histopathological

A COMPARATIVE STUDY OF SINGLE VERSUS DOUBLE LAYER CLOSURE ON LOWER SEGMENT CAESAREAN SCAR

Directory of Open Access Journals (Sweden)

Kirtirekha Mohapatra

2016-10-01

Full Text Available BACKGROUND There are few issues in modern obstetrics that have been as controversial as management of a woman with a prior caesarean delivery. Hence, it is required to have evidence based correct practice of this surgical procedure. Healing of the uterine incision and the strength of the scar should be the most important consideration. The aim of the study is to compare the effect of technique of uterine closure (Single Layer vs. Double Layer on subsequent pregnancies and to find out, which technique has a better maternal and neonatal outcome by strengthening the scar. MATERIALS AND METHODS 500 cases of previous caesarean section pregnancies were taken, 250 from single layer closure group and 250 from double layer closure group. The mode of delivery during present pregnancy was noted. Integrity of scar, thickness of scar, presence of adhesion were documented. The neonates were observed. Results were compared so as to draw an inference about the better method. RESULTS Mean age between the two groups were similar. Majority did not have history of premature rupture of membrane during previous pregnancy. Postoperative complications were more when double layer closure of uterine scar was done in index surgery. Interpregnancy gap of <3 years was more commonly present in double layer closure group (52.8% in double layer versus 34.8% in single layer. Single layer had more scar tenderness (21.2%, thinned out scars (34.6%, incomplete ruptures (7.1% and complete ruptures (2.8% than double layer closure group. Neonatal outcomes were not statistically different in both the groups. CONCLUSION Double layer uterine closure seems to have better impact on scar integrity as compared to single layer uterine closure.

Comparison of single and dual layer detector blocks for pre-clinical MRI–PET

International Nuclear Information System (INIS)

Thompson, Christopher; Stortz, Greg; Goertzen, Andrew; Berg, Eric; Retière, Fabrice; Kozlowski, Piotr; Ryner, Lawrence; Sossi, Vesna; Zhang, Xuezhu

2013-01-01

Dual or multi-layer crystal blocks have been proposed to minimise the radial blurring effect in PET scanners with small ring diameters. We measured two potential PET detector blocks' performance in a configuration which would allow 16 blocks in a ring which could be inserted in a small animal 7T MRI scanner. Two crystal sizes, 1.60×1.60 mm 2 and 1.20×1.20 mm 2 , were investigated. Single layer blocks had 10 or 12 mm deep crystals, the dual layer blocks had 4 mm deep crystals on the top layer and 6 mm deep crystals on the bottom layer. The crystals in the dual layer blocks are offset by ½ of the crystal pitch to allow for purely geometric crystal identification. Both were read out with SensL 4×4 SiPM arrays. The software identifies 64 crystals in the single layer and either 85 or 113 crystals in the dual layer array, (either 49 or 64 in the lower layers and 36 or 49 in the upper layers). All the crystals were clearly visible in the crystal identification images and their resolvability indexes (average FWHM/crystal separation) were shown to range from 0.29 for the best single layer block to 0.33 for the densest dual layer block. The best coincidence response FWHM was 0.95 mm for the densest block at the centre of the field. This degraded to 1.83 mm at a simulated radial offset of 16 mm from the centre, while the single layer crystals blurred this result to 3.4 mm. The energy resolution was 16.4±2.2% averaged over the 113 crystals of the densest block

Management of recurrent epistaxis in an anticoagulated patient by temporarily closing the nares with sutures.

Science.gov (United States)

Eng, Chee-Yean; Yew, Teck-Aun; Ng, Wai-Siene; El-Hawrani, Amged S

2008-04-01

We describe an unusual case of recurrent, refractory anterior epistaxis in an 86-year-old man with two mechanical heart valves who was on permanent warfarin therapy. His numerous episodes of epistaxis were incited by chronic nose-picking and strong nose-blowing, practices that he continued to engage in despite repeated medical advice to stop. Stopping his anticoagulation therapy was not considered as a management option because of an unacceptably high risk that this would lead to a thromboembolic event. Eventually, we temporarily sutured his nares closed, and his nosebleeds ceased. The suturing was performed in the ward with local anesthesia. This procedure was simple to perform,fairly well tolerated, easily reversible, and highly effective.

Modified end-to-side double-layer open pancreaticogastrostomy after Whipple procedure: surgical tips for a safe anastomosis.

Science.gov (United States)

Dalla Valle, Raffaele; Rossini, Matteo; Lamecchi, Laura; Iaria, Maurizio

2018-03-01

Pancreatic fistula (PF) remains the Achilles' heel of pancreaticoduodenectomy (PD). Pancreaticogastrostomy (PG) appears to be associated with a lower risk of postoperative leak according to recent evidence. We started to fashion PG, especially in soft pancreas, modifying the original technique described by Bassi. At our institution, 105 PD procedures were carried out from January 2011 to December 2016; pancreatic-enteric continuity was restored by PG in 35 cases. Superior mesenteric/portal vein resection/reconstruction was necessary in three patients. A total of 34/35 patients underwent PG with an open anterior gastrostomy approach. Briefly, our double-layer PG anastomosis (illustrated by a video) starts with a posterior row of interrupted absorbable 4/0 monofilament sutures including the gastric serosa and the pancreatic capsule. It is essential to mobilize the left pancreas for 4-5 cm and to shape the posterior gastrostomy shorter than the pancreatic stump. After a wide anterior auxiliary gastrostomy the pancreas is invaginated into the stomach and an interrupted row of sutures between the posterior gastric wall (full-thickness) and the body of the pancreatic stump is fashioned. The anterior gastrostomy is closed with an absorbable running suture. Finally, a further layer of sutures is applied over the posterior suture line between the gastric serosa and the pancreatic capsule. The 90-day postoperative mortality was nihil. No biliary leakage was detected and the overall PF rate was 11.4% (4/35) according to the ISGPF study group. Only one patient suffered a grade B PF (in this case, PG was carried out only through a posterior gastrostomy), whereas three patients had a minor (grade A) PF. Our modified PG proved to be safe and easy to perform, while it carried excellent outcomes even in the setting of soft pancreas. Despite the limited number of cases, such modified PG appears promising, particularly for pancreatic remnants at higher risk of PF.

The Incidence and Topographic Distribution of Sutures Including Wormian Bones in Human Skulls.

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Cirpan, Sibel; Aksu, Funda; Mas, Nuket

2015-07-01

The Wormian Bones are accessory bones located within the cranial sutures and fontanelles. The present article examines the incidence of Wormian Bones and compares the number and topographic distribution between the sutures including Wormian Bones in skulls of West Anatolian Population. One hundred fifty crania were examined. The parameters evaluated in the present study were as follows: the rate of skulls including Wormian Bones; the topographic distribution and frequencies of the sutures including Wormian Bones; the number of these sutures for each skull; the name and number of sutures that were bilaterally and symmetrically located on the right and left side of skull (paired sutures) and which coincidentally had Wormian Bones for each skull; the differences of frequencies between the paired sutures including Wormian Bones. The rate of skulls including Wormian Bones was determined as 59.3%. The maximum and minimum numbers of sutures, including Wormian Bones, were 6 in 1 skull and 1 in each of 30 skulls, respectively. The maximum and minimum rates of sutures that had Wormian Bones were found in left lambdoid 40.7% and right occipitomastoid 1.3% sutures, respectively. There was only a significant difference between the rate of right and left squamous sutures (P = 0.04). Forty-five skulls were including 55 pairs of bilaterally and symmetrically located sutures that coincidentally had Wormian Bones in each pair. Each of 35 skulls had 1 pair of sutures including Wormian Bones and each of 10 skulls had 2 pairs. In the present study, the rate of Wormian Bones was determined as 59.3% in West Anatolian Population. This incidence rate is considerably lower than the other reports, and it may be as a result of racial variations. These divergent bones were more frequently found in left lambdoid sutures (40.7%) and less frequently in right occipitomastoid sutures (1.3%). This study may guide the investigators dealing with the neurosurgery, orthopedy, radiology, anatomy, and

Cosmetic outcome of three sutures levator aponeurosis tuck procedure in congenital ptosis

International Nuclear Information System (INIS)

Hussain, I.

2006-01-01

To determine the results of three sutures aponeurosis tuck procedure in patients with congenital ptosis. Twenty-four eyes of 20 patients (13 males and 7 females) with congenital ptosis were included in the study. All these lids had either good or fair levator function. Amount of ptosis in all lids were measured before surgery and their mean calculated. Single surgeon performed the three sutures levator aponeurosis tuck procedure on all these lids. Degree of ptosis, after surgery was measured on multiple occasions and mean of measures of last follow-up was calculated. At this stage, the patients' satisfaction level was also documented. Mean amount of ptosis was 3.25 +- 0.99 mm before surgery and 0.33 +- 0.56 mm after surgery (p < 0.0001). Satisfaction level of 18 (90%) patients was 70-90%, while in 2 (10%) patients it was 50-60%. (author)

Single-layer MoS2 electronics.

Science.gov (United States)

Lembke, Dominik; Bertolazzi, Simone; Kis, Andras

2015-01-20

CONSPECTUS: Atomic crystals of two-dimensional materials consisting of single sheets extracted from layered materials are gaining increasing attention. The most well-known material from this group is graphene, a single layer of graphite that can be extracted from the bulk material or grown on a suitable substrate. Its discovery has given rise to intense research effort culminating in the 2010 Nobel Prize in physics awarded to Andre Geim and Konstantin Novoselov. Graphene however represents only the proverbial tip of the iceberg, and increasing attention of researchers is now turning towards the veritable zoo of so-called "other 2D materials". They have properties complementary to graphene, which in its pristine form lacks a bandgap: MoS2, for example, is a semiconductor, while NbSe2 is a superconductor. They could hold the key to important practical applications and new scientific discoveries in the two-dimensional limit. This family of materials has been studied since the 1960s, but most of the research focused on their tribological applications: MoS2 is best known today as a high-performance dry lubricant for ultrahigh-vacuum applications and in car engines. The realization that single layers of MoS2 and related materials could also be used in functional electronic devices where they could offer advantages compared with silicon or graphene created a renewed interest in these materials. MoS2 is currently gaining the most attention because the material is easily available in the form of a mineral, molybdenite, but other 2D transition metal dichalcogenide (TMD) semiconductors are expected to have qualitatively similar properties. In this Account, we describe recent progress in the area of single-layer MoS2-based devices for electronic circuits. We will start with MoS2 transistors, which showed for the first time that devices based on MoS2 and related TMDs could have electrical properties on the same level as other, more established semiconducting materials. This

Single-layer graphene on silicon nitride micromembrane resonators

DEFF Research Database (Denmark)

Schmid, Silvan; Bagci, Tolga; Zeuthen, Emil

2014-01-01

Due to their low mass, high quality factor, and good optical properties, silicon nitride (SiN) micromembrane resonators are widely used in force and mass sensing applications, particularly in optomechanics. The metallization of such membranes would enable an electronic integration with the prospect...... for exciting new devices, such as optoelectromechanical transducers. Here, we add a single-layer graphene on SiN micromembranes and compare electromechanical coupling and mechanical properties to bare dielectric membranes and to membranes metallized with an aluminium layer. The electrostatic coupling...

Rhinoplasty: a simplified, three-stitch, open tip suture technique. Part I: primary rhinoplasty.

Science.gov (United States)

Daniel, R K

1999-04-01

Tip suture techniques offer a reliable and dramatic method of tip modification without needing to interrupt the alar rim strip or add tip grafts. The present simplified three-stitch technique consists of the following: (1) a strut suture to fix the columella strut between the crura, (2) bilateral domal creation sutures to create tip definition, and (3) a domal equalization suture to narrow and align the domes. If required, columella septal sutures can be added; either a dorsal rotational suture or a transfixion projection suture can be used. This simplified method represents a refinement based on more than 13 years of experience with tip suture techniques. It does not require a complex operative sequence or specialized sutures. Primary indications are moderate tip deformities of inadequate definition and excessive width and certain specific tip deformities, including the parenthesis tip and nostril/tip disproportion. The primary contraindications are for patients with minor tip deformities that are best done through a closed approach and those with severe tip deformities requiring an open structure graft. The technique is simple, efficacious, and easily learned.

Strength of bone tunnel versus suture anchor and push-lock construct in Broström repair.

Science.gov (United States)

Giza, Eric; Nathe, Ryan; Nathe, Tyler; Anderson, Matthew; Campanelli, Valentina

2012-06-01

Operative treatment of mechanical ankle instability is indicated for patients who have had multiple sprains and have continued episodes of instability despite bracing and rehabilitation. Anatomic reconstruction has been shown to have improved outcomes and return to sport as compared with nonanatomic reconstruction. The use of 2 suture anchors and a push-lock anchor is equal to 2 bone tunnels in strength to failure for anatomic Broström repair. Controlled laboratory study. In 7 matched pairs of human cadaver ankles, the calcaneofibular ligament (CFL) and anterior talofibular ligament (ATFL) were incised from their origin on the fibula. A No. 2 Fiberwire suture was placed into the CFL and a separate suture into the ATFL in a running Krackow fashion with a total of 4 locking loops. In 1 ankle of the matched pair, the ligaments were repaired to their anatomic insertion with bone tunnels. In the other, 2 suture anchors were used to reattach the ligaments to their anatomic origins, and a push-lock was used proximally to reinforce these suture anchors. The ligaments were cyclically loaded 20 times and then tested to failure. Torque to failure, degrees to failure, and stiffness were measured. The authors performed a matched pair analysis. An a priori power analysis of 0.8 demonstrated 6 pairs were needed to show a difference of 30% with a 15% standard error at a significance level of .05. There was no difference in the degrees to failure, torque to failure, and stiffness. A post hoc power analysis of torque to failure showed a power of .89 with 7 samples. Power for initial stiffness was .97 with 7 samples. Eleven of 14 specimens failed at either the suture anchor or the bone tunnel. There is no statistical difference in strength or stiffness for a suture anchor and push-lock construct as compared with a bone tunnel construct for an anatomic repair of the lateral ligaments of the ankle. The use of suture anchors in lateral ligament stabilization allows for a smaller

Grenvillean sutures zones in the northern portion of the Cuyania terrane, Republica Argentina. geophysical evidence

International Nuclear Information System (INIS)

Chernicoff, C.; Vujovich, G.

2004-01-01

In the northern portion of the Cuyania terrane there is geophysical evidence for the ocurrence of two ancient WNW suture zones, corresponding to the Guandacol and Vinchina lineaments. The location of these sutures is consistent with analogous structures in Laurentia, in the Ouachita embayment region, where the Grenvillean orogen trends WNW. It is argued that the WNW transform faults pertaining to the Ouachita rift would have developed as a result of a reactivation of compressional structures of identical orientation associated to the accretion of Grenvillean terranes. The Guandacol and Vinchina lineaments would have been in physical continuity with analogous megastructures in the Ouachita embayment region, and they both would have originated as compressional structures, later reactivated as transcurrent fault zones during the late Proterozoic early Paleozoic. The interpretation of the Guandacol and Vinchina lineaments as Grenvillean suture zones would add more complexity to the Cuyania terrane, with respect to what has been described up to now; they could precede the amalgamation of the Pie de Palo and Precordillera terranes (constituents of the Cuyania composite terrane) [es

Quadriceps tendon rupture: a biomechanical comparison of transosseous equivalent double-row suture anchor versus transosseous tunnel repair.

Science.gov (United States)

Hart, Nathan D; Wallace, Matthew K; Scovell, J Field; Krupp, Ryan J; Cook, Chad; Wyland, Douglas J

2012-09-01

Quadriceps rupture off the patella is traditionally repaired by a transosseous tunnel technique, although a single-row suture anchor repair has recently been described. This study biomechanically tested a new transosseous equivalent (TE) double-row suture anchor technique compared with the transosseous repair for quadriceps repair. After simulated quadriceps-patella avulsion in 10 matched cadaveric knees, repairs were completed by either a three tunnel transosseous (TT = 5) or a TE suture anchor (TE = 5) technique. Double-row repairs were done using two 5.5 Bio-Corkscrew FT (fully threaded) (Arthrex, Inc., Naples, FL, USA) and two 3.5 Bio-PushLock anchors (Arthrex, Inc., Naples, FL, USA) with all 10 repairs done with #2 FiberWire suture (Arthrex, Inc., Naples, FL). Cyclic testing from 50 to 250 N for 250 cycles and pull to failure load (1 mm/s) were undertaken. Gap formation and ultimate tensile load (N) were recorded and stiffness data (N/mm) were calculated. Statistical analysis was performed using a Mann-Whitney U test and survival characteristics examined with Kaplan-Meier test. No significant difference was found between the TE and TT groups in stiffness (TE = 134 +/- 15 N/mm, TT = 132 +/- 26 N/mm, p = 0.28). The TE group had significantly less ultimate tensile load (N) compared with the TT group (TE = 447 +/- 86 N, TT = 591 +/- 84 N, p = 0.04), with all failures occurring at the suture eyelets. Although both quadriceps repairs were sufficiently strong, the transosseous repairs were stronger than the TE suture anchor repairs. The repair stiffness and gap formation were similar between the groups.

Kernel Function Tuning for Single-Layer Neural Networks

Czech Academy of Sciences Publication Activity Database

Vidnerová, Petra; Neruda, Roman

-, accepted 28.11. 2017 (2018) ISSN 2278-0149 R&D Projects: GA ČR GA15-18108S Institutional support: RVO:67985807 Keywords : single-layer neural networks * kernel methods * kernel function * optimisation Subject RIV: IN - Informatics, Computer Science http://www.ijmerr.com/

Breakthrough to Non-Vacuum Deposition of Single-Crystal, Ultra-Thin, Homogeneous Nanoparticle Layers: A Better Alternative to Chemical Bath Deposition and Atomic Layer Deposition

Directory of Open Access Journals (Sweden)

Yu-Kuang Liao

2017-04-01

Full Text Available Most thin-film techniques require a multiple vacuum process, and cannot produce high-coverage continuous thin films with the thickness of a few nanometers on rough surfaces. We present a new ”paradigm shift” non-vacuum process to deposit high-quality, ultra-thin, single-crystal layers of coalesced sulfide nanoparticles (NPs with controllable thickness down to a few nanometers, based on thermal decomposition. This provides high-coverage, homogeneous thickness, and large-area deposition over a rough surface, with little material loss or liquid chemical waste, and deposition rates of 10 nm/min. This technique can potentially replace conventional thin-film deposition methods, such as atomic layer deposition (ALD and chemical bath deposition (CBD as used by the Cu(In,GaSe2 (CIGS thin-film solar cell industry for decades. We demonstrate 32% improvement of CIGS thin-film solar cell efficiency in comparison to reference devices prepared by conventional CBD deposition method by depositing the ZnS NPs buffer layer using the new process. The new ZnS NPs layer allows reduction of an intrinsic ZnO layer, which can lead to severe shunt leakage in case of a CBD buffer layer. This leads to a 65% relative efficiency increase.

Absorbable Polydioxanone (PDS) suture provides fewer wound complications than polyester (ethibond) suture in acute Tendo-Achilles rupture repair

LENUS (Irish Health Repository)

Baig, M N

2017-05-01

We prospectively studied acute Achilles tendon rupture in patients over a two 2-year period and reviewed the causes, outcome and complications. There were 53 patients included with acute Achilles rupture with minimum follow up period of 6 months. We compared the outcomes including infection rate and Boyden score between the two groups repaired by Polydioxanone and Polyester respectively. All infected cases had a suture repair using the polyester suture. The difference in the infection rate was highly significant between the 2 groups (p=0.001). All 34 patients (100%) in the PDS group had good \\/ excellent results based on the Boyden clinical assessment. Conversely, only 16 patients 9(68.4%) had good or excellent results IN Polyester repair group. Patients treated with a non- absorbable suture (ethibond) material for repair had a higher incidence infection and worse Boyden scores than the absorbable PDS group.

Biomechanical evaluation of knotless anatomical double-layer double-row rotator cuff repair: a comparative ex vivo study.

Science.gov (United States)

Hepp, Pierre; Osterhoff, Georg; Engel, Thomas; Marquass, Bastian; Klink, Thomas; Josten, Christoph

2009-07-01

The layered configuration of the rotator cuff tendon is not taken into account in classic rotator cuff tendon repair techniques. The mechanical properties of (1) the classic double-row technique, (2) a double-layer double-row (DLDR) technique in simple suture configuration, and (3) a DLDR technique in mattress suture configuration are significantly different. Controlled laboratory study. Twenty-four sheep shoulders were assigned to 3 repair groups of full-thickness infraspinatus tears: group 1, traditional double-row repair; group 2, DLDR anchor repair with simple suture configuration; and group 3, DLDR knotless repair with mattress suture configuration. After ultrasound evaluation of the repair, each specimen was cyclically loaded with 10 to 100 N for 50 cycles. Each specimen was then loaded to failure at a rate of 1 mm/s. There were no statistically significant differences among the 3 testing groups for the mean footprint area. The cyclic loading test revealed no significant difference among the 3 groups with regard to elongation. For the load-to-failure test, groups 2 and 3 showed no differences in ultimate tensile load when compared with group 1. However, when compared to group 2, group 3 was found to have significantly higher values regarding ultimate load, ultimate elongation, and energy absorbed. The DLDR fixation techniques may provide strength of initial repair comparable with that of commonly used double-row techniques. When compared with the knotless technique with mattress sutures, simple suture configuration of DLDR repair may be too weak. Knotless DLDR rotator cuff repair may (1) restore the footprint by the use of double-row principles and (2) enable restoration of the shape and profile. Double-layer double-row fixation in mattress suture configuration has initial fixation strength comparable with that of the classic double-row fixation and so may potentially improve functional results of rotator cuff repair.

A microfluidic galvanic cell on a single layer of paper

Science.gov (United States)

Purohit, Krutarth H.; Emrani, Saina; Rodriguez, Sandra; Liaw, Shi-Shen; Pham, Linda; Galvan, Vicente; Domalaon, Kryls; Gomez, Frank A.; Haan, John L.

2016-06-01

Paper microfluidics is used to produce single layer galvanic and hybrid cells to produce energy that could power paper-based analytical sensors. When two aqueous streams are absorbed onto paper to establish co-laminar flow, the streams stay in contact with each other with limited mixing. The interface at which mixing occurs acts as a charge-transfer region, eliminating the need for a salt bridge. We designed a Cusbnd Zn galvanic cell that powers an LED when two are placed in series. We also used more powerful redox couples (formate and silver, formate and permanganate) to produce higher power density (18 and 3.1 mW mg-1 Pd). These power densities are greater than previously reported paper microfluidic fuel cells using formate or methanol. The single layer design is much more simplified than previous reports of multi-layer galvanic cells on paper.

Glue versus suture for mesh fixation in inguinal hernia repair.

Science.gov (United States)

Chandrasekar, Shruthi; Jeyakumar, S; Ganapathy, Tharun

2018-03-22

Inguinal hernia is one of the most common surgical problem presenting to the surgical OPD. Surgery is the mainstay of treatment for inguinal hernia today. Surgery for inguinal hernia has undergone a great evolution over a period of several centuries. Lichenstein's tension free hernioplasty is the one of the first surgeries taught to a surgical resident. The main aim of surgeries in this era is to give the best possible results with the least possible pain, scar and time. This has given rise to so many modifications to the classical Lichenstein's procedure and also to laparoscopic hernioplasty. Pain after inguinal hernia surgery is found to be debilitating and altering the quality of life in several patients, which has been attributed to the traumatic fixation of the mesh with sutures. This has paved way to the development of various atraumatic methods of fixation, tissue glue is one such development. Hence this study, to compare traumatic and atraumatic methods of mesh fixation in inguinal hernia repair. The aim of this study was to compare suture fixation versus tissue glue fixation of the mesh in inguinal hernia repair. Primary objective was to compare the immediate and chronic post-operative pain. Secondary objective was to compare the time taken for the procedure by the two methods in use and also to compare the presence of any complications. and methodology: This study was done in the General Surgery department of XXX hospital, medical college and research centre, kattangulathur after Ethics committee clearance. It is a single blinded study. The study was done on 51 patients consenting for the study and meeting the inclusion criterias from the period of March 2016 to August 2017 out of which 26 were selected for glue mesh fixation and 25 for suture mesh fixation according to simple randomization. The suture group patients underwent classical Lichenstein's tension free hernioplasty and the glue group underwent Lichenstein's hernioplasty with glue where dots of

Necrotizing Fasciitis Secondary to a Primary Suture for Anoperineal Trauma by Motorcycle Accident in a Healthy Adult

Directory of Open Access Journals (Sweden)

Susumu Saigusa

2015-01-01

Full Text Available A 41-year-old man experienced a swollen scrotum three days after a motorcycle accident and presented to our hospital. He had had a primary suture repair for anoperineal trauma in an outside hospital at the time of the injury. He presented to us with general fatigue, low grade fevers, and perineal pain. Abdominal computed tomography showed subcutaneous emphysema from the scrotum to the left chest. The sutured wound had foul-smelling discharge and white exudate. We made the diagnosis of necrotizing fasciitis and immediately opened the sutured wound and performed initial debridement and lavage with copious irrigation. We continued antibiotics and lavage of the wound until the infection was controlled. Fortunately, the necrotizing fasciitis did not worsen and he was discharged after 15 days. Our experience indicates that anoperineal injuries should not be closed without careful and intensive follow-up due to the potential of developing necrotizing fasciitis.

Selective exfoliation of single-layer graphene from non-uniform graphene grown on Cu

International Nuclear Information System (INIS)

Lim, Jae-Young; Lee, Jae-Hyun; Jang, Hyeon-Sik; Whang, Dongmok; Joo, Won-Jae; Hwang, SungWoo

2015-01-01

Graphene growth on a copper surface via metal-catalyzed chemical vapor deposition has several advantages in terms of providing high-quality graphene with the potential for scale-up, but the product is usually inhomogeneous due to the inability to control the graphene layer growth. The non-uniform regions strongly affect the reliability of the graphene in practical electronic applications. Herein, we report a novel graphene transfer method that allows for the selective exfoliation of single-layer graphene from non-uniform graphene grown on a Cu foil. Differences in the interlayer bonding energy are exploited to mechanically separate only the top single-layer graphene and transfer this to an arbitrary substrate. The dry-transferred single-layer graphene showed electrical characteristics that were more uniform than those of graphene transferred using conventional wet-etching transfer steps. (paper)

LENA Conversion Foils Using Single-Layer Graphene, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Our key innovation will be the use of single-layer graphene as LENA conversion foils, with appropriate microgrids and nanogrids to support the foils. Phase I...

Arthroscopic Hip Labral Repair: The Iberian Suture Technique

OpenAIRE

Stubbs, Allston J.; Andersen, Jason S.; Mannava, Sandeep; Wooster, Benjamin M.; Howse, Elizabeth A.; Winter, S. Bradley

2014-01-01

Arthroscopic hip labral repair has beneficial short-term outcomes; however, debate exists regarding ideal surgical labral repair technique. This technical note presents an arthroscopic repair technique that uses intrasubstance labral suture passage to restore the chondrolabral interface. This “Iberian suture technique” allows for an anatomic repair while posing minimal risk of damage to the labral and chondral tissues.

Water desalination with a single-layer MoS2 nanopore

Science.gov (United States)

Heiranian, Mohammad; Farimani, Amir Barati; Aluru, Narayana R.

2015-10-01

Efficient desalination of water continues to be a problem facing the society. Advances in nanotechnology have led to the development of a variety of nanoporous membranes for water purification. Here we show, by performing molecular dynamics simulations, that a nanopore in a single-layer molybdenum disulfide can effectively reject ions and allow transport of water at a high rate. More than 88% of ions are rejected by membranes having pore areas ranging from 20 to 60 Å2. Water flux is found to be two to five orders of magnitude greater than that of other known nanoporous membranes. Pore chemistry is shown to play a significant role in modulating the water flux. Pores with only molybdenum atoms on their edges lead to higher fluxes, which are ~70% greater than that of graphene nanopores. These observations are explained by permeation coefficients, energy barriers, water density and velocity distributions in the pores.

Symbol "&" suture to control atonic postpartum hemorrhage with placenta previa accreta.

Science.gov (United States)

Li, Guang Tai; Li, Xiao Fan; Liu, Ya Jing; Li, Wei; Xu, Hong Mei

2015-02-01

To evaluate the efficacy and safety of a symbol "&" compression suture technique in controlling severe atonic postpartum hemorrhage with placenta previa accreta during cesarean delivery. Nine women with heavy postpartum bleeding from uterine inertia and placenta previa percret, which did not react to conventional initial management protocols, were underwent the suture in the shape of symbol "&" in China Meitan General Hospital. The suture procedure was to staple the anterior and posterior walls (of the lower uterine segment as well as corpus uterus) together using number 1 chromic catgut, with a cross at about 2 cm above the upper boundary of lower uterine segment. Symbol "&" compression suture was capable of stanching the postpartum hemorrhage immediately in all nine women. None of these patients developed complications related to this method. Subsequent pregnancies after the suture were occurred in two women and delivered with repeat cesarean section. Symbol "&" compression suture is a simple, safe and highly effective technique to control the treatment-resistant uterine atonic bleeding, particularly in previous cesarean scar at lower segment and placenta previa accreta.

EFFECTS OF DIFFERENT SUTURE MATERIALS ON TISSUE HEALING

Directory of Open Access Journals (Sweden)

Fırat SELVİ

2016-01-01

Full Text Available Purpose: The purpose of this study was to investigate the healing differences in between four different widely used suture materials in the oral surgery practice, including silk (Perma- Hand; Ethicon, INC., Somerville, NJ, USA, polypropylene (Prolene; Ethicon, INC., Somerville, NJ, USA, coated polyglactin 910 (Ethicon, INC., Somerville, NJ, USA. and polyglecaprone 25 (Ethicon, INC., Somerville, NJ, USA . Materials and Methods: 20 male rats were randomly allocated into two groups depending on their sacrification days (post-operative 1st and the 7th days. Four longitudinal incision wounds, each 1cm in size, were created on the dorsum of each animal which were then primarily closed with four different types of sutures. Results: The effects of these suture materials on soft tissue healing were compared histopathologically, by means of density of the cells, necrosis, fibrosis, foreign body reaction, the presence of cells of acute and chronic infection. No statistically significant difference was observed between the groups regarding the density of the cells, necrosis, fibrosis, foreign body reaction, and the presence of the cells of acute & chronic infections. Of note, propylene showed slightly less tissue reaction among the other materials. Conclusion: The results of our study showed that there is no only one ideal suture material for surgical practice. The factors related to the patient, the type of the surgery and the quality of the tissue are important to decide an appropriate suture material.

A novel technique of rotator cuff repair using spinal needle and suture loop

Directory of Open Access Journals (Sweden)

Muzaffar Nasir

2010-11-01

Full Text Available Abstract Background We present a simple technique of arthroscopic rotator cuff repair using a spinal needle and suture loop. Methods With the arthroscope laterally, a spinal needle looped with PDS is inserted percutaneously into the shoulder posteriorly and penetrated through the healthy posterior cuff tear margin. Anteriorly, another spinal needle loaded with PDS is inserted percutaneously to engage the healthy tissue at the anterior tear margin. The suture in the anterior needle is then delivered into the suture loop of the posterior needle using a suture retriever. The posterior needle and loop are then pulled out carrying the anterior suture with it. The two limbs of this suture are then retrieved through a cannula for knotting. The same procedure is then repeated for additional suturing. Suture anchors placed over the greater tuberosity are used to complete the repair. Conclusion This is an easy method of rotator cuff repair using simple instruments and lesser time, hence can be employed at centers with less equipment and at reduced cost to the patient.

Electrically Anisotropic Layered Perovskite Single Crystal

KAUST Repository

Li, Ting-You

2016-04-01

Organic-inorganic hybrid perovskites (OIHPs), which are promising materials for electronic and optoelectronic applications (1-10), have made into layered organic-inorganic hybrid perovskites (LOIHPs). These LOIHPs have been applied to thin-film transistors, solar cells and tunable wavelength phosphors (11-18). It is known that devices fabricated with single crystal exhibit the superior performance, which makes the growth of large-sized single crystals critical for future device applications (19-23). However, the difficulty in growing large-sized LOIHPs single crystal with superior electrical properties limits their practical applications. Here, we report a method to grow the centimeter-scaled LOIHP single crystal of [(HOC2H4NH3)2PbI4], demonstrating the potentials in mass production. After that, we reveal anisotropic electrical and optoelectronic properties which proved the carrier propagating along inorganic framework. The carrier mobility of in-inorganic-plane (in-plane) devices shows the average value of 45 cm2 V–1 s–1 which is about 100 times greater than the record of LOIHP devices (15), showing the importance of single crystal in device application. Moreover, the LOIHP single crystals show its ultra-short carrier lifetime of 42.7 ps and photoluminescence quantum efficiency (PLQE) of 25.4 %. We expect this report to be a start of LOIHPs for advanced applications in which the anisotropic properties are needed (24-25), and meets the demand of high-speed applications and fast-response applications.

Editorial Commentary: All-Suture Anchors, Foam Blocks, and Biomechanical Testing.

Science.gov (United States)

Brand, Jefferson C

2017-06-01

Barber's biomechanical work is well known to Arthroscopy's readers as thorough, comprehensive, and inclusive of new designs as they become available. In "All-Suture Anchors: Biomechanical Analysis of Pullout Strength, Displacement, and Failure Mode," the latest iteration, Barber and Herbert test all-suture anchors in both porcine femurs and biphasic foam. While we await in vivo clinical trials that compare all-suture anchors to currently used anchors, Barber and Herbert have provided data to inform anchor choice, and using their biomechanical data at time zero from all-suture anchor trials in an animal model, we can determine the anchors' feasibility for human clinical investigations. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Single-port laparoscopic myomectomy using a new single-port transumbilical morcellation system: initial clinical study.

Science.gov (United States)

Kim, Yong-Wook; Park, Byung-Joon; Ro, Duck-Yeong; Kim, Tae-Eung

2010-01-01

To evaluate the feasibility of single-port laparoscopic myomectomy with transumbilical morcellation and suturing. Continuing prospective study (Canadian Task Force classification II-3). University hospital. Fifteen patients who underwent single-port laparoscopic myomectomy between September 2008 and October 2009 to remove single or multiple uterine myomas, at least 1 in each patient measuring greater than 4 cm in diameter. All single-port laparoscopic myomectomy procedures were performed by a single surgeon (Dr. Y.W. Kim). Myomas were extracted transumbilically by cutting the myomas into smaller pieces with a knife or a conventional electromechanical morcellator. After making a single 1.5- to 2.0-cm umbilical incision, the single-port system, created with a wound retractor and a surgical glove, was inserted. All operations were performed using conventional rigid straight laparoscopic instruments. Laparoscopic suturing was performed in intramural myomas and some subserosal myomas. Patient mean (SD; range) age was 38.3 (5.6; 29-49) years. The number of myomas per patient was 1.6 (1.4; 1-6). The diameter of the largest myomas was 6.1 (1.5; 4.2-9.6) cm. In 4 patients, only a knife was required for transumbilical extraction of myomas, and in 11 patients, transumbilical morcellation with an electromechanical morcellator with or without a knife was used. Transumbilical drainage tubes were inserted into the pelvic cavity in 11 of 15 patients. Operative time was 96.7 (33.8; 35-150) minutes. The decrease in postoperative hemoglobin concentration was 1.8 (1.2; 0.4-3.6) g/dL. During the operations, no patients required blood transfusion. No patients developed postoperative fever. Neither bowel injury nor urinary tract injury occurred in any patient. The postoperative hospital stay was 3.1 (0.8; 2-4) days. Single-port transumbilical morcellation using a conventional electromechanical morcellator with or without a knife is feasible. Single-port laparoscopic myomectomy is an

Electrochemistry at the edge of a single graphene layer in a nanopore

DEFF Research Database (Denmark)

Banerjee, Sutanuka; Shim, Jeong; Rivera, J.

2013-01-01

We study the electrochemistry of single layer graphene edges using a nanopore-based structure consisting of stacked graphene and AlO dielectric layers. Nanopores, with diameters ranging from 5 to 20 nm, are formed by an electron beam sculpting process on the stacked layers. This leads to a unique...

Diverse and tunable electronic structures of single-layer metal phosphorus trichalcogenides for photocatalytic water splitting

International Nuclear Information System (INIS)

Liu, Jian; Li, Xi-Bo; Wang, Da; Liu, Li-Min; Lau, Woon-Ming; Peng, Ping

2014-01-01

The family of bulk metal phosphorus trichalcogenides (APX 3 , A = M II , M 0.5 I M 0.5 III ; X = S, Se; M I , M II , and M III represent Group-I, Group-II, and Group-III metals, respectively) has attracted great attentions because such materials not only own magnetic and ferroelectric properties, but also exhibit excellent properties in hydrogen storage and lithium battery because of the layered structures. Many layered materials have been exfoliated into two-dimensional (2D) materials, and they show distinct electronic properties compared with their bulks. Here we present a systematical study of single-layer metal phosphorus trichalcogenides by density functional theory calculations. The results show that the single layer metal phosphorus trichalcogenides have very low formation energies, which indicates that the exfoliation of single layer APX 3 should not be difficult. The family of single layer metal phosphorus trichalcogenides exhibits a large range of band gaps from 1.77 to 3.94 eV, and the electronic structures are greatly affected by the metal or the chalcogenide atoms. The calculated band edges of metal phosphorus trichalcogenides further reveal that single-layer ZnPSe 3 , CdPSe 3 , Ag 0.5 Sc 0.5 PSe 3 , and Ag 0.5 In 0.5 PX 3 (X = S and Se) have both suitable band gaps for visible-light driving and sufficient over-potentials for water splitting. More fascinatingly, single-layer Ag 0.5 Sc 0.5 PSe 3 is a direct band gap semiconductor, and the calculated optical absorption further convinces that such materials own outstanding properties for light absorption. Such results demonstrate that the single layer metal phosphorus trichalcogenides own high stability, versatile electronic properties, and high optical absorption, thus such materials have great chances to be high efficient photocatalysts for water-splitting

Immunostimulatory sutures that treat local disease recurrence following primary tumor resection

Energy Technology Data Exchange (ETDEWEB)

Intra, Janjira; Zhang Xueqing; Salem, Aliasger K [Division of Pharmaceutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242 (United States); Williams, Robin L; Zhu Xiaoyan [Department of Surgery, Roy J and Lucille Carver College of Medicine, University of Iowa, Iowa City, IA 52242 (United States); Sandler, Anthony D, E-mail: aliasger-salem@uiowa.edu [Department of Surgery and Center for Cancer and Immunology Research, Children' s National Medical Center, Washington DC 20010 (United States)

2011-02-15

Neuroblastoma is a common childhood cancer that often results in progressive minimal residual disease after primary tumor resection. Cytosine-phosphorothioate-guanine oligonucleotides (CpG ODN) have been reported to induce potent anti-tumor immune responses. In this communication, we report on the development of a CpG ODN-loaded suture that can close up the wound following tumor excision and provide sustained localized delivery of CpG ODN to treat local disease recurrence. The suture was prepared by melt extruding a mixture of polylactic acid-co-glycolic acid (PLGA 75:25 0.47 dL g{sup -1}) pellets and CpG ODN 1826. Scanning electron microscopy images showed that the sutures were free of defects and cracks. UV spectrophotometry measurements at 260 nm showed that sutures provide sustained release of CpG ODN over 35 days. Syngeneic female A/J mice were inoculated subcutaneously with 1 x 10{sup 6} Neuro-2a murine neuroblastoma wild-type cells and tumors were grown between 5 to 10 mm before the tumors were excised. Wounds from the tumor resection were closed using CpG ODN-loaded sutures and/or polyglycolic acid Vicryl suture. Suppression of neuroblastoma recurrence and mouse survival were significantly higher in mice where wounds were closed using the CpG ODN-loaded sutures relative to all other groups. (communication)

Arthroscopic suture anchor repair of the lateral ligament ankle complex: a cadaveric study.

Science.gov (United States)

Giza, Eric; Shin, Edward C; Wong, Stephanie E; Acevedo, Jorge I; Mangone, Peter G; Olson, Kirstina; Anderson, Matthew J

2013-11-01

Operative treatment of mechanical ankle instability is indicated for patients with multiple sprains and continued episodes of instability. Open repair of the lateral ankle ligaments involves exposure of the attenuated ligaments and advancement back to their anatomic insertions on the fibula using bone tunnels or suture implants. Open and arthroscopic fixation are equal in strength to failure for anatomic Broström repair. Controlled laboratory study. Seven matched pairs of human cadaveric ankle specimens were randomized into 2 groups of anatomic Broström repair: open or arthroscopic. The calcaneofibular ligament and anterior talofibular ligament were excised from their origin on the fibula. In the open repair group, 2 suture anchors were used to reattach the ligaments to their anatomic origins. In the arthroscopic repair group, identical suture anchors were used for repair via an arthroscopic technique. The ligaments were cyclically loaded 20 times and then tested to failure. Torque to failure, degrees to failure, initial stiffness, and working stiffness were measured. A matched-pair analysis was performed. Power analysis of 0.8 demonstrated that 7 pairs needed to show a difference of 30%, with a 15% standard error at a significance level of α = .05. There was no difference in the degrees to failure, torque to failure, or stiffness for the repaired ligament complex. Nine of 14 specimens failed at the suture anchor. There is no statistical difference in strength or stiffness of a traditional open repair as compared with an arthroscopic anatomic repair of the lateral ligaments of the ankle. An arthroscopic technique can be considered for lateral ligament stabilization in patients with mild to moderate mechanical instability.

Evaluation of a New Knotless Suture Anchor Repair in Acute Achilles Tendon Ruptures: A Biomechanical Comparison of Three Techniques.

Science.gov (United States)

Cottom, James M; Baker, Joseph S; Richardson, Phillip E; Maker, Jared M

Acute ruptures of the Achilles tendon are a common injury, and debate has continued in published studies on how best to treat these injuries. Specifically, controversy exists regarding the surgical approaches for Achilles tendon repair when one considers percutaneous versus open repair. The present study investigated the biomechanical strength of 3 different techniques for Achilles tendon repair in a cadaveric model. A total of 36 specimens were divided into 3 groups, each of which received a different construct. The first group received a traditional Krackow suture repair, the second group was repaired using a jig-assisted percutaneous suture, and the third group received a repair using a jig-assisted percutaneous repair modified with suture anchors placed into the calcaneus. The specimens were tested with cyclical loading and to ultimate failure. Cyclical loading showed a trend toward a stronger repair with the use of suture anchors after 10 cycles (p = .295), 500 cycles (p = .120), and 1000 cycles (p = .040). The ultimate load to failure was greatest in the group repaired with the modified knotless technique using the suture anchors (p = .098). The results of the present study show a clear trend toward a stronger construct in Achilles repair using a knotless suture anchor technique, which might translate to a faster return to activity and be more resistant to an early and aggressive rehabilitation protocol. Further clinical studies are warranted to evaluate this technique in a patient population. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Stress-Softening and Residual Strain Effects in Suture Materials

Directory of Open Access Journals (Sweden)

Alex Elías-Zúñiga

2013-01-01

Full Text Available This work focuses on the experimental characterization of suture material samples of MonoPlus, Monosyn, polyglycolic acid, polydioxanone 2–0, polydioxanone 4–0, poly(glycolide-co-epsilon-caprolactone, nylon, and polypropylene when subjected to cyclic loading and unloading conditions. It is found that all tested suture materials exhibit stress-softening and residual strain effects related to the microstructural material damage upon deformation from the natural, undistorted state of the virgin suture material. To predict experimental observations, a new constitutive material model that takes into account stress-softening and residual strain effects is developed. The basis of this model is the inclusion of a phenomenological nonmonotonous softening function that depends on the strain intensity between loading and unloading cycles. The theory is illustrated by modifying the non-Gaussian average-stretch, full-network model to capture stress-softening and residual strains by using pseudoelasticity concepts. It is shown that results obtained from theoretical simulations compare well with suture material experimental data.

Fixation of the Achilles tendon insertion using suture button technology.

Science.gov (United States)

Fanter, Nathan J; Davis, Edward W; Baker, Champ L

2012-09-01

In the operative treatment of Achilles insertional tendinopathy, no guidelines exist concerning which form of fixation of the Achilles tendon insertion is superior. Transcalcaneal drill pin passage does not place any major plantar structures at risk, and the addition of a Krackow stitch and suture button to the fixation technique provides a significant increase in ultimate load to failure in Achilles tendon insertional repairs. Controlled laboratory study. The Achilles tendon insertions in 6 fresh-frozen cadaveric ankles were detached, and transcalcaneal drill pins were passed. Plantar dissection took place to evaluate the drill pin relationship to the plantar fascia, lateral plantar nerve and artery, flexor digitorum longus tendon, and master knot of Henry. The Achilles tendons were then repaired with a double-row suture anchor construct alone or with a suture button and Krackow stitch added to the double-row suture anchor construct. The repairs were then tested to maximum load to failure at 20 mm/min. The mode of failure was recorded, and the mean maximum load to failure was assessed using the Student t test for distributions with equal variance. Transcalcaneal drill pin passage did not place any selected anatomic structures at risk. The mean maximum load to failure for the suture bridge group was 239.2 N; it was 391.4 N for the group with the suture button (P = .014). The lateral plantar artery was the structure placed at greatest risk from drill pin placement, with a mean distance of 22.7 mm (range, 16.5-29.2 mm) between the pin and artery. In this laboratory study, transcalcaneal drill pin passage appeared to be anatomically safe, and the use of suture button technology with a Krackow stitch for Achilles tendon insertional repair significantly increased repair strength. Achilles tendon insertional repair with suture button fixation and a Krackow stitch may facilitate the earlier institution of postoperative rehabilitation and improve clinical outcomes.

Identification and dynamics of a cryptic suture zone in tropical rainforest

Science.gov (United States)

Moritz, C.; Hoskin, C.J.; MacKenzie, J.B.; Phillips, B.L.; Tonione, M.; Silva, N.; VanDerWal, J.; Williams, S.E.; Graham, C.H.

2009-01-01

Suture zones, shared regions of secondary contact between long-isolated lineages, are natural laboratories for studying divergence and speciation. For tropical rainforest, the existence of suture zones and their significance for speciation has been controversial. Using comparative phylogeographic evidence, we locate a morphologically cryptic suture zone in the Australian Wet Tropics rainforest. Fourteen out of 18 contacts involve morphologically cryptic phylogeographic lineages, with mtDNA sequence divergences ranging from 2 to 15 per cent. Contact zones are significantly clustered in a suture zone located between two major Quaternary refugia. Within this area, there is a trend for secondary contacts to occur in regions with low environmental suitability relative to both adjacent refugia and, by inference, the parental lineages. The extent and form of reproductive isolation among interacting lineages varies across species, ranging from random admixture to speciation, in one case via reinforcement. Comparative phylogeographic studies, combined with environmental analysis at a fine-scale and across varying climates, can generate new insights into suture zone formation and to diversification processes in species-rich tropical rainforests. As arenas for evolutionary experimentation, suture zones merit special attention for conservation. PMID:19203915

Fabrication of a single layer graphene by copper intercalation on a SiC(0001) surface

International Nuclear Information System (INIS)

Yagyu, Kazuma; Tochihara, Hiroshi; Tomokage, Hajime; Suzuki, Takayuki; Tajiri, Takayuki; Kohno, Atsushi; Takahashi, Kazutoshi

2014-01-01

Cu atoms deposited on a zero layer graphene grown on a SiC(0001) substrate, intercalate between the zero layer graphene and the SiC substrate after the thermal annealing above 600 °C, forming a Cu-intercalated single layer graphene. On the Cu-intercalated single layer graphene, a graphene lattice with superstructure due to moiré pattern is observed by scanning tunneling microscopy, and specific linear dispersion at the K ¯ point as well as a characteristic peak in a C 1s core level spectrum, which is originated from a free-standing graphene, is confirmed by photoemission spectroscopy. The Cu-intercalated single layer graphene is found to be n-doped

Sequential selective same-day suture removal in the management of post-keratoplasty astigmatism.

Science.gov (United States)

Fares, U; Mokashi, A A; Elalfy, M S; Dua, H S

2013-09-01

In a previous study, we proposed that corneal topography performed 30-40 min after the initial suture removal can identify the next set of sutures requiring removal, for the treatment of post-keratoplasty astigmatism. The aim of this study was to evaluate the effect of removing subsequent sets of sutures at the same sitting. 10/0 nylon interrupted sutures were placed, to secure the graft-host junction, at the time of keratoplasty. Topography was performed using Pentacam (Oculus) before suture removal. The sutures to be removed in the steep semi-meridians were identified and removed at the slit-lamp biomicroscope. Topography was repeated 30-40 min post suture removal, the new steep semi-meridians determined, and the next set of sutures to be removed were identified and removed accordingly. Topography was repeated 4-6 weeks later and the magnitude of topographic astigmatism was recorded. A paired-samples t-test was used to evaluate the impact of selective suture removal on reducing the magnitude of topographic and refractive astigmatism. Twenty eyes of 20 patients underwent sequential selective same-day suture removal (SSSS) after corneal transplantation. This study showed that the topographic astigmatism decreased by about 46.7% (3.68 D) and the refractive astigmatism decreased by about 37.7% (2.61 D) following SSSS. Vector calculations also show a significant reduction of both topographic and refractive astigmatism (P<0.001). SSSS may help patients to achieve satisfactory vision more quickly and reduce the number of follow-up visits required post keratoplasty.

Protecting nickel with graphene spin-filtering membranes: A single layer is enough

Energy Technology Data Exchange (ETDEWEB)

Martin, M.-B.; Dlubak, B.; Piquemal-Banci, M.; Collin, S.; Petroff, F.; Anane, A.; Fert, A.; Seneor, P. [Unité Mixte de Physique CNRS/Thales, 1 Avenue Augustin Fresnel, 91767 Palaiseau, France and Université Paris Sud, 91405 Orsay (France); Weatherup, R. S.; Hofmann, S.; Robertson, J. [Department of Engineering, University of Cambridge, Cambridge CB21PZ (United Kingdom); Yang, H. [IBS Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Blume, R. [Helmholtz-Zentrum Berlin fur Materialien und Energie, 12489 Berlin (Germany); Schloegl, R. [Department of Inorganic Chemistry, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin (Germany)

2015-07-06

We report on the demonstration of ferromagnetic spin injectors for spintronics which are protected against oxidation through passivation by a single layer of graphene. The graphene monolayer is directly grown by catalytic chemical vapor deposition on pre-patterned nickel electrodes. X-ray photoelectron spectroscopy reveals that even with its monoatomic thickness, monolayer graphene still efficiently protects spin sources against oxidation in ambient air. The resulting single layer passivated electrodes are integrated into spin valves and demonstrated to act as spin polarizers. Strikingly, the atom-thick graphene layer is shown to be sufficient to induce a characteristic spin filtering effect evidenced through the sign reversal of the measured magnetoresistance.

Ameloblastin inhibits cranial suture closure by modulating MSX2 expression and proliferation.

Directory of Open Access Journals (Sweden)

Phimon Atsawasuwan

Full Text Available Deformities of cranial sutures such as craniosynostosis and enlarged parietal foramina greatly impact human development and quality of life. Here we have examined the role of the extracellular matrix protein ameloblastin (Ambn, a recent addition to the family of non-collagenous extracellular bone matrix proteins, in craniofacial bone development and suture formation. Using RT-PCR, western blot and immunohistochemistry, Ambn was localized in mouse calvarial bone and adjacent condensed mesenchyme. Five-fold Ambn overexpression in a K14-driven transgenic mouse model resulted in delayed posterior frontal suture fusion and incomplete suture closure. Moreover, Ambn overexpressor skulls weighed 13.2% less, their interfrontal bones were 35.3% thinner, and the width between frontal bones plus interfrontal suture was 14.3% wider. Ambn overexpressing mice also featured reduced cell proliferation in suture blastemas and in mesenchymal cells from posterior frontal sutures. There was a more than 2-fold reduction of Msx2 in Ambn overexpressing calvariae and suture mesenchymal cells, and this effect was inversely proportionate to the level of Ambn overexpression in different cell lines. The reduction of Msx2 expression as a result of Ambn overexpression was further enhanced in the presence of the MEK/ERK pathway inhibitor O126. Finally, Ambn overexpression significantly reduced Msx2 down-stream target gene expression levels, including osteogenic transcription factors Runx2 and Osx, the bone matrix proteins Ibsp, ColI, Ocn and Opn, and the cell cycle-related gene CcnD1. Together, these data suggest that Ambn plays a crucial role in the regulation of cranial bone growth and suture closure via Msx 2 suppression and proliferation inhibition.

FGFR2c-mediated ERK-MAPK activity regulates coronal suture development

Science.gov (United States)

Pfaff, Miles J.; Xue, Ke; Li, Li; Horowitz, Mark C.; Steinbacher, Derek M.; Eswarakumar, Jacob V.P.

2017-01-01

Fibroblast growth factor receptor 2 (FGFR2) signaling is critical for proper craniofacial development. A gain-of-function mutation in the 2c splice variant of the receptor’s gene is associated with Crouzon syndrome, which is characterized by craniosynostosis, the premature fusion of one or more of the cranial vault sutures, leading to craniofacial maldevelopment. Insight into the molecular mechanism of craniosynostosis has identified the ERK-MAPK signaling cascade as a critical regulator of suture patency. The aim of this study is to investigate the role of FGFR2c-induced ERK-MAPK activation in the regulation of coronal suture development. Loss-of-function and gain-of-function Fgfr2c mutant mice have overlapping phenotypes, including coronal synostosis and craniofacial dysmorphia. In vivo analysis of coronal sutures in loss-of-function and gain-of-function models demonstrated fundamentally different pathogenesis underlying coronal suture synostosis. Calvarial osteoblasts from gain-of-function mice demonstrated enhanced osteoblastic function and maturation with concomitant increase in ERK-MAPK activation. In vitro inhibition with the ERK protein inhibitor U0126 mitigated ERK protein activation levels with a concomitant reduction in alkaline phosphatase activity. This study identifies FGFR2c-mediated ERK-MAPK signaling as a key mediator of craniofacial growth and coronal suture development. Furthermore, our results solve the apparent paradox between loss-of-function and gain-of-function FGFR2c mutants with respect to coronal suture synostosis. PMID:27034231

A combination of subcuticular suture and sterile Micropore tape compared with conventional interrupted sutures for skin closure. A controlled trial.

Science.gov (United States)

Taube, M.; Porter, R. J.; Lord, P. H.

1983-01-01

We have conducted a controlled trial to compare skin closure using conventional interrupted sutures with a combination of subcuticular suture and sterile Micropore tape in 169 patients undergoing appendicectomy, inguinal herniorrhaphy, or saphenofemoral ligation. We have found that the combination technique consistently gives a better cosmetic result and that the tape acts well as a dressing, is convenient, and is well tolerated by patients. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:6344732

Phonon-limited mobility in n-type single-layer MoS2 from first principles

DEFF Research Database (Denmark)

Kaasbjerg, Kristen; Thygesen, Kristian S.; Jacobsen, Karsten W.

2012-01-01

We study the phonon-limited mobility in intrinsic n-type single-layer MoS2 for temperatures T > 100 K. The materials properties including the electron-phonon interaction are calculated from first principles and the deformation potentials and Frohlich interaction in single-layer MoS2 are established...... to recent experimental findings for the mobility in single-layer MoS2 (similar to 200 cm(2)V(-1)s(-1)), our results indicate that mobilities close to the intrinsic phonon-limited mobility can be achieved in two-dimensional materials via dielectric engineering that effectively screens static Coulomb...

Local Delivery of Growth Factors Using Coated Suture Material

Directory of Open Access Journals (Sweden)

T. F. Fuchs

2012-01-01

Full Text Available The optimization of healing processes in a wide range of tissues represents a central point for surgical research. One approach is to stimulate healing processes with growth factors. These substances have a short half-life and therefore it seems useful to administer these substances locally rather than systemically. One possible method of local delivery is to incorporate growth factors into a bioabsorbable poly (D, L-lactide suspension (PDLLA and coat suture material. The aim of the present study was to establish a procedure for the local delivery of growth factors using coated suture material. Sutures coated with growth factors were tested in an animal model. Anastomoses of the colon were created in a rat model using monofilament sutures. These were either untreated or coated with PDLLA coating alone or coated with PDLLA incorporating insulin—like growth factor-I (IGF-I. The anastomoses were subjected to biomechanical, histological, and immunohistochemical examination. After 3 days the treated groups showed a significantly greater capacity to withstand biomechanical stress than the control groups. This finding was supported by the results of the histomorphometric. The results of the study indicate that it is possible to deliver bioactive growth factors locally using PDLLA coated suture material. Healing processes can thus be stimulated locally without subjecting the whole organism to potentially damaging high systemic doses.

[Treatment of calcaneal avulsion fractures with twinfix suture anchors fixation].

Science.gov (United States)

Zhao, Bin-xiu; Wang, Kun-zheng; Wang, Chun-sheng; Xie, Yue; Dai, Zhi-tang; Liu, Gang; Liu, Wei-dong

2011-06-01

For the calcaneal avulsion fracture, the current method is more commonly used screws or Kirschner wire to fix fracture fragment. This article intended to explore the feasibility and clinical efficacy for the treatment of avulsion fractures with TwinFix suture anchors. From July 2007 to November 2010, 21 patients were reviewed, including 15 males and 6 females, ranging in age from 49 to 65 years,with a mean of 58.7 years. Twelve patients had nodules in the right heel and 9 patients had nodules in the left heel. All the patients had closed fractures. The typical preoperative symptoms of the patients included pain in the upper heel and weak in heel lift. Body examination results: palpable sense of bone rubbing in the back of the heel, and swelling in the heel. Surgery treatment with TwinFix suture anchors performed as follows : to fix TwinFix suture anchors into the calcaneal body, then to drill the fracture block, to make the double strand suture through the fracture holes, to knot the suture eachother to fix the block, and to use stitch to fix the remaining suture in the Achilles tendon in order to improve the block fixation. The criteria of the AOFAS Foot and Ankle Surgery by the United States Association of ankle-rear foot functional recovery was used to evaluate the Achilles tendon. Total average score was (95.5 +/- 3.12) points, including pain items of(38.5 +/- 2.18) points,the average score of functional items of (49.5 +/- 3.09) points,and power lines of 10 points in all patients. Twenty-one patients got an excellent result, 16 good and 5 poor. The methods of treatment for the calcaneal avulsion fractures with TwinFix suture anchors is a simple operation, and have excellent clinical effect, which is worthy of promotion.

Effect of robotic manipulation on unidirectional barbed suture integrity: evaluation of tensile strength and sliding force.

Science.gov (United States)

Kaushik, Dharam; Clay, Kevin; Hossain, S G M; Park, Eugene; Nelson, Carl A; LaGrange, Chad A

2012-06-01

One of the more challenging portions of robot-assisted radical prostatectomy (RARP) is the urethrovesical anastomosis. Because of this, a unidirectional absorbable barbed suture (V-Loc(™)) has been used to complete the anastomosis with better efficiency and less tension. The effect of robotic needle driver manipulation on barbed suture is unknown. Therefore, the aim of this study is to determine whether robotic manipulation decreases the tensile strength and peak sliding force of V-Loc barbed suture. Fifty-six V-Loc sutures were compared with 56 Maxon sutures. All sutures were 3-0 caliber. Half of the sutures in each group were manipulated with a da Vinci(®) robot large needle driver five times over a 5 cm length of suture. The other half was not manipulated. Breaking force was determined by placing sutures in a Bose ElectroForce load testing device. For sliding force testing, 28 V-Loc sutures were manipulated in the same fashion and compared with 28 nonmanipulated V-Loc sutures. Peak force needed to make the suture slip backward in porcine small intestine was determined to be the sliding force. Scanning electron microscopy of the barbs before and after robotic manipulation was also performed. The mean difference in breaking forces for manipulated vs nonmanipulated Maxon sutures was 4.52 N (P=0.004). The mean difference in breaking forces for manipulated vs nonmanipulated V-Loc sutures was 1.30 N (P=0.046). The manipulated V-Loc group demonstrated a lower peak sliding force compared with the nonmanipulated group (0.76 vs 0.88 N, P=0.199). Electron microscopy revealed minor structural damage to the barbs and suture. Tensile strength and peak sliding force of V-Loc suture is decreased by robotic manipulation. This is likely because of structural damage to the suture and barbs. This structural damage, however, is likely not clinically significant.

Integral Suture-Handling Techniques for Arthroscopic Sliding Knots

OpenAIRE

Kanchanatawan, Wichan; Kongtharvonskul, Jatupon; Dorjiee, Gem; Suppauksorn, Sunikom; Pornvoranunt, Umpire; Karchana, Pongsakorn

2016-01-01

In arthroscopic tissue repair, the final step is achieving adequate tissue approximation with a secure knot. The sliding knot is widely preferred over the nonsliding knot, with numerous publications describing knot configurations. However, in the literature there are few published descriptions of suture-handling techniques, even though they are fundamental to arthroscopic knot tying. We describe integral suture-handling techniques for arthroscopic sliding knots to improve the surgeon's perfor...

Biomechanical Comparison of Standard and Linked Single-Row Rotator Cuff Repairs in a Human Cadaver Model.

Science.gov (United States)

Meisel, Adam F; Henninger, Heath B; Barber, F Alan; Getelman, Mark H

2017-05-01

The purpose of this study was to evaluate the time zero cyclic and failure loading properties of a linked single-row rotator cuff repair compared with a standard simple suture single-row repair using triple-loaded suture anchors. Eighteen human cadaveric shoulders from 9 matched pairs were dissected, and full-thickness supraspinatus tears were created. The tendon cross-sectional area was recorded. In each pair, one side was repaired with a linked single-row construct and the other with a simple suture single-row construct, both using 2 triple-loaded suture anchors. After preloading, specimens were cycled to 1 MPa of effective stress at 1 Hz for 500 cycles, and gap formation was recorded with a digital video system. Samples were then loaded to failure, and modes of failure were recorded. There was no statistical difference in peak gap formation between the control and linked constructs (3.6 ± 0.9 mm and 3.6 ± 1.2 mm, respectively; P = .697). Both constructs averaged below a 5-mm cyclic failure threshold. There was no statistical difference in ultimate load to failure between the control and linked repair (511.1 ± 139.0 N and 561.2 ± 131.8 N, respectively; P = .164), and both groups reached failure at loads similar to previous studies. Constructs failed predominantly via tissue tearing parallel to the medial suture line. The linked repair performed similarly to the simple single-row repair. Both constructs demonstrated high ultimate load to failure and good resistance to gap formation with cyclic loading, validating the time zero strength of both constructs in a human cadaveric model. The linked repair provided equivalent resistance to gap formation and failure loads compared with simple suture single-row repairs with triple-loaded suture anchors. This suggests that the linked repair is a simplified rip-stop configuration using the existing suture that may perform similarly to current rotator cuff repair techniques. Copyright © 2016 Arthroscopy

Strong piezoelectricity in single-layer graphene deposited on SiO2 grating substrates.

Science.gov (United States)

da Cunha Rodrigues, Gonçalo; Zelenovskiy, Pavel; Romanyuk, Konstantin; Luchkin, Sergey; Kopelevich, Yakov; Kholkin, Andrei

2015-06-25

Electromechanical response of materials is a key property for various applications ranging from actuators to sophisticated nanoelectromechanical systems. Here electromechanical properties of the single-layer graphene transferred onto SiO2 calibration grating substrates is studied via piezoresponse force microscopy and confocal Raman spectroscopy. The correlation of mechanical strains in graphene layer with the substrate morphology is established via Raman mapping. Apparent vertical piezoresponse from the single-layer graphene supported by underlying SiO2 structure is observed by piezoresponse force microscopy. The calculated vertical piezocoefficient is about 1.4 nm V(-1), that is, much higher than that of the conventional piezoelectric materials such as lead zirconate titanate and comparable to that of relaxor single crystals. The observed piezoresponse and achieved strain in graphene are associated with the chemical interaction of graphene's carbon atoms with the oxygen from underlying SiO2. The results provide a basis for future applications of graphene layers for sensing, actuating and energy harvesting.

The effectiveness of the double B-lynch suture as a modification in the treatment of intractable postpartum haemorrhage.

Science.gov (United States)

Şahin, Hanifi; Soylu Karapınar, Oya; Şahin, Eda Adeviye; Dolapçıoğlu, Kenan; Baloğlu, Ali

2018-03-20

A broader range of more effective compression techniques are needed in the patients who have an intractable postpartum haemorrhage due to uterine atony despite medical treatment and B-Lynch sutures. The aim of this study was to report the outcome of a series of patients with haemorrhage who were managed by double B-Lynch suture. Fourteen patients who were treated in a tertiary hospital between July 2010 and February 2015 were included in the study. The intractable haemorrhage rate was 0.35% over 5 years (14/4000 births). Bleeding was controlled in all the patients with a double B-Lynch suture. The mean age of the patients was 24 ± 3.4 years. The mean estimated blood loss was 1696 ± 272.075 mL, and the mean transfusion rate was 4.2 ± 2.5 units. Pregnancy was observed in five patients at follow up. The double B-Lynch suture seems to be an effective and reliable solution to an intractable postpartum haemorrhage resulting from uterine atony and has no unfavourable impacts on fertility. It should be considered before the use of any aggressive surgical techniques such as a hypogastric artery ligation or a hysterectomy. This the first study to investigate the effectiveness of the double B-Lynch suture, and we showed that the hysterectomy and/or hypogastric artery ligation rate can be decreased by adding a second B-Lynch suture in cases where the medical treatment or a single B-Lynch has failed. Impact statement What is already known on the subject? Uterine atony is the most common cause of a primary postpartum haemorrhage. When a simple massage of the uterus and medication failed to manage this condition, various surgical solutions have been sought, including uterine compression sutures, uterine artery ligation, devascularisation of the uterus, internal iliac artery ligation and, ultimately, a hysterectomy. The B-Lynch suturing technique is particularly useful because of its simplicity of application, life-saving potential, relative safety and capacity

Suture associated corneal abscess three years after cataract surgery ...

African Journals Online (AJOL)

The abscess was carefully removed on slit lamp using blunt tipped forceps without breaking the thin membrane covering it. There was a deep corneal depression at the bottom of which was found a loose 10/0 nylon corneoscleral suture. Another loose suture was present at the 12 o'clock position surrounded by stromal ...

Development of a penetration friction apparatus (PFA) to measure the frictional performance of surgical suture.

Science.gov (United States)

Zhang, Gangqiang; Ren, Tianhui; Lette, Walter; Zeng, Xiangqiong; van der Heide, Emile

2017-10-01

Nowadays there is a wide variety of surgical sutures available in the market. Surgical sutures have different sizes, structures, materials and coatings, whereas they are being used for various surgeries. The frictional performances of surgical sutures have been found to play a vital role in their functionality. The high friction force of surgical sutures in the suturing process may cause inflammation and pain to the person, leading to a longer recovery time, and the second trauma of soft or fragile tissue. Thus, the investigation into the frictional performance of surgical suture is essential. Despite the unquestionable fact, little is actually known on the friction performances of surgical suture-tissue due to the lack of appropriate test equipment. This study presents a new penetration friction apparatus (PFA) that allowed for the evaluation of the friction performances of various surgical needles and sutures during the suturing process, under different contact conditions. It considered the deformation of tissue and can realize the puncture force measurements of surgical needles as well as the friction force of surgical sutures. The developed PFA could accurately evaluate and understand the frictional behaviour of surgical suture-tissue in the simulating clinical conditions. The forces measured by the PFA showed the same trend as that reported in literatures. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nonabsorbable-Suture-Induced Osteomyelitis: A Case Report and Review of the Literature

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Cheng Hong Yeo

2012-01-01

Full Text Available We are reporting a case of nonabsorbable suture-induced osteomyelitis in patient who had an open rotator cuff repair with nonabsorbable Ethibond anchor suture. Patient in this case presented with very subtle clinical features of osteomyelitis of the left proximal humerus 15 years after initial rotator cuff repair surgery. Literature had shown that deep infection following rotator cuff repairs, although rare, can be easily missed and can cause severe complications. Absorbable suture had been demonstrated to be more superior, in terms of rate of deep infection, as compared to nonabsorbable suture when used in rotator cuff repair surgery. Both absorbable and nonabsorbable suture had been demonstrated to have similar mechanical properties by several different studies. The case demonstrated that initial presentation of deep infection can be subtle and easily missed by clinicians and leads to further complications.

Anisotropic carrier mobility in single- and bi-layer C3N sheets

Science.gov (United States)

Wang, Xueyan; Li, Qingfang; Wang, Haifeng; Gao, Yan; Hou, Juan; Shao, Jianxin

2018-05-01

Based on the density functional theory combined with the Boltzmann transport equation with relaxation time approximation, we investigate the electronic structure and predict the carrier mobility of single- and bi-layer newly fabricated 2D carbon nitrides C3N. Although C3N sheets possess graphene-like planar hexagonal structure, the calculated carrier mobility is remarkably anisotropic, which is found mainly induced by the anisotropic effective masses and deformation potential constants. Importantly, we find that both the electron and hole mobilities are considerable high, for example, the hole mobility along the armchair direction of single-layer C3N sheets can arrive as high as 1.08 ×104 cm2 V-1 s-1, greatly larger than that of C2N-h2D and many other typical 2D materials. Owing to the high and anisotropic carrier mobility and appropriate band gap, single- and bi-layer semiconducting C3N sheets may have great potential applications in high performance electronic and optoelectronic devices.

Study of the mechanical properties of single- layer and multi-layer metallic coatings with protective-decorative applications

Directory of Open Access Journals (Sweden)

Cherneva Sabina

2018-01-01

Full Text Available Single thin coating of matt nickel (Nimat, a mirror bright copper (Cubright, a mirror bright nickel (Nibright and their combinations were electrochemically deposited on brass substrate with thickness 500 μm. The basic aim was electrodeposition of two-layer Cubright/Nimat and Nibright/Cubright systems, and three-layer Nibright Cubrigh/Nimat system, which are among the most widely applied protective and decorative systems in light and medium operating conditions of corrosion. The thicknesses of the obtained films varied from 1 μm to 3.25 μm. They were investigated via nanoindentation experiments, in order to characterize their basic physical and mechanical characteristics, related with their good adhesion and corrosion protective ability, as well as ensuring the integrity of the system “protective coating/substrate” to possible mechanical, dynamic and/or thermal stresses. As a result, load-displacement curves were obtained and indentation hardness and indentation modulus were calculated using the Oliver & Pharr approximation method. The dependence of the indentation modulus and the indentation hardness on the depth of the indentation, surface morphology and structure of the obtained coatings, their texture and surface roughness were investigated too. The obtained results showed that the three-layer Nibright/Cubright /Niimat/CuZn37 system has highest indentation modulus and indentation hardness, following by two-layer Nibright/Cubright system and single layer coatings.

Biomechanical Performance of Medial Row Suture Placement Relative to the Musculotendinous Junction in Transosseous Equivalent Suture Bridge Double-Row Rotator Cuff Repair.

Science.gov (United States)

Virk, Mandeep S; Bruce, Benjamin; Hussey, Kristen E; Thomas, Jacqueline M; Luthringer, Tyler A; Shewman, Elizabeth F; Wang, Vincent M; Verma, Nikhil N; Romeo, Anthony A; Cole, Brian J

2017-02-01

To compare the biomechanical performance of medial row suture placement relative to the musculotendinous junction (MTJ) in a cadaveric transosseous equivalent suture bridge (TOE-SB) double-row (DR) rotator cuff repair (RCR) model. A TOE-SB DR technique was used to reattach experimentally created supraspinatus tendon tears in 9 pairs of human cadaveric shoulders. The medial row sutures were passed either near the MTJ (MTJ group) or 10 mm lateral to the MTJ (rotator cuff tendon [RCT] group). After the supraspinatus repair, the specimens underwent cyclic loading and load to failure tests. The localized displacement of the markers affixed to the tendon surface was measured with an optical tracking system. The MTJ group showed a significantly higher (P = .03) medial row failure (5/9; 3 during cyclic testing and 2 during load to failure testing) compared with the RCT group (0/9). The mean number of cycles completed during cyclic testing was lower in the MTJ group (77) compared with the RCT group (100; P = .07) because 3 specimens failed in the MTJ group during cyclic loading. There were no significant differences between the 2 study groups with respect to biomechanical properties during the load to failure testing. In a cadaveric TOE-SB DR RCR model, medial row sutures through the MTJ results in a significantly higher rate of medial row failure. In rotator cuff tears with tendon tissue loss, passage of medial row sutures through the MTJ should be avoided in a TOE-SB RCR technique because of the risk of medial row failure. Copyright © 2016. Published by Elsevier Inc.

Gap opening and tuning in single-layer graphene with combined electric and magnetic field modulation

Institute of Scientific and Technical Information of China (English)

Lin Xin; Wang Hai-Long; Pan Hui; Xu Huai-Zhe

2011-01-01

The energy band structure of single-layer graphene under one-dimensional electric and magnetic field modulation is theoretically investigated. The criterion for bandgap opening at the Dirac point is analytically derived with a two-fold degeneracy second-order perturbation method. It is shown that a direct or an indirect bandgap semiconductor could be realized in a single-layer graphene under some specific configurations of the electric and magnetic field arrangement. Due to the bandgap generated in the single-layer graphene, the Klein tunneling observed in pristine graphene is completely suppressed.

Synthesis of few layer single crystal graphene grains on platinum by chemical vapour deposition

Directory of Open Access Journals (Sweden)

S. Karamat

2015-08-01

Full Text Available The present competition of graphene electronics demands an efficient route which produces high quality and large area graphene. Chemical vapour deposition technique, where hydrocarbons dissociate in to active carbon species and form graphene layer on the desired metal catalyst via nucleation is considered as the most suitable method. In this study, single layer graphene with the presence of few layer single crystal graphene grains were grown on Pt foil via chemical vapour deposition. The higher growth temperature changes the surface morphology of the Pt foil so a delicate process of hydrogen bubbling was used to peel off graphene from Pt foil samples with the mechanical support of photoresist and further transferred to SiO2/Si substrates for analysis. Optical microscopy of the graphene transferred samples showed the regions of single layer along with different oriented graphene domains. Two type of interlayer stacking sequences, Bernal and twisted, were observed in the graphene grains. The presence of different stacking sequences in the graphene layers influence the electronic and optical properties; in Bernal stacking the band gap can be tunable and in twisted stacking the overall sheet resistance can be reduced. Grain boundaries of Pt provides low energy sites to the carbon species, therefore the nucleation of grains are more at the boundaries. The stacking order and the number of layers in grains were seen more clearly with scanning electron microscopy. Raman spectroscopy showed high quality graphene samples due to very small D peak. 2D Raman peak for single layer graphene showed full width half maximum (FWHM value of 30 cm−1. At points A, B and C, Bernal stacked grain showed FWHM values of 51.22, 58.45 and 64.72 cm−1, while twisted stacked grain showed the FWHM values of 27.26, 28.83 and 20.99 cm−1, respectively. FWHM values of 2D peak of Bernal stacked grain showed an increase of 20–30 cm−1 as compare to single layer graphene

Valley polarization in magnetically doped single-layer transition-metal dichalcogenides

KAUST Repository

Cheng, Yingchun; Zhang, Q. Y.; Schwingenschlö gl, Udo

2014-01-01

We demonstrate that valley polarization can be induced and controlled in semiconducting single-layer transition-metal dichalcogenides by magnetic doping, which is important for spintronics, valleytronics, and photonics devices. As an example, we

Pullout strength of cement-augmented and wide-suture transosseous fixation in the greater tuberosity.

Science.gov (United States)

Shi, Brendan Y; Diaz, Miguel; Belkoff, Stephen M; Srikumaran, Uma

2017-12-01

Obtaining strong fixation in low-density bone is increasingly critical in surgical repair of rotator cuff tears because of the aging population. To evaluate two new methods of improving pullout strength of transosseous rotator cuff repair in low-density bone, we analyzed the effects of 1) using 2-mm suture tape instead of no. 2 suture and 2) augmenting the lateral tunnel with cement. Eleven pairs of osteopenic or osteoporotic cadaveric humeri were identified by dual-energy x-ray absorptiometry. One bone tunnel and one suture were placed in the heads of 22 specimens. Five randomly selected pairs were repaired with no. 2 suture; the other six pairs were repaired with 2-mm suture tape. One side of each pair received lateral tunnel cement augmentation. Specimens were tested to suture pullout. Data were fitted to multivariate models that accounted for bone mineral density and other specimen characteristics. Two specimens were excluded because of knot-slipping during testing. Use of suture tape versus no. 2 suture conferred a 75-N increase (95% CI: 37, 113) in pullout strength (PCement augmentation conferred a 42-N improvement (95% CI: 10, 75; P=0.011). Other significant predictors of pullout strength were age, sex, and bone mineral density. We show two methods of improving the fixation strength of transosseous rotator cuff repairs in low-density bone: using 2-mm suture tape instead of no. 2 suture and augmenting the lateral tunnel with cement. These methods may improve the feasibility of transosseous repairs in an aging patient population. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of In Utero Thyroxine Exposure on Murine Cranial Suture Growth.

Directory of Open Access Journals (Sweden)

R Nicole Howie

Full Text Available Large scale surveillance studies, case studies, as well as cohort studies have identified the influence of thyroid hormones on calvarial growth and development. Surveillance data suggests maternal thyroid disorders (hyperthyroidism, hypothyroidism with pharmacological replacement, and Maternal Graves Disease are linked to as much as a 2.5 fold increased risk for craniosynostosis. Craniosynostosis is the premature fusion of one or more calvarial growth sites (sutures prior to the completion of brain expansion. Thyroid hormones maintain proper bone mineral densities by interacting with growth hormone and aiding in the regulation of insulin like growth factors (IGFs. Disruption of this hormonal control of bone physiology may lead to altered bone dynamics thereby increasing the risk for craniosynostosis. In order to elucidate the effect of exogenous thyroxine exposure on cranial suture growth and morphology, wild type C57BL6 mouse litters were exposed to thyroxine in utero (control = no treatment; low ~167 ng per day; high ~667 ng per day. Thyroxine exposed mice demonstrated craniofacial dysmorphology (brachycranic. High dose exposed mice showed diminished area of the coronal and widening of the sagittal sutures indicative of premature fusion and compensatory growth. Presence of thyroid receptors was confirmed for the murine cranial suture and markers of proliferation and osteogenesis were increased in sutures from exposed mice. Increased Htra1 and Igf1 gene expression were found in sutures from high dose exposed individuals. Pathways related to the HTRA1/IGF axis, specifically Akt and Wnt, demonstrated evidence of increased activity. Overall our data suggest that maternal exogenous thyroxine exposure can drive calvarial growth alterations and altered suture morphology.

Effects of In Utero Thyroxine Exposure on Murine Cranial Suture Growth.

Science.gov (United States)

Howie, R Nicole; Durham, Emily L; Black, Laurel; Bennfors, Grace; Parsons, Trish E; Elsalanty, Mohammed E; Yu, Jack C; Weinberg, Seth M; Cray, James J

2016-01-01

Large scale surveillance studies, case studies, as well as cohort studies have identified the influence of thyroid hormones on calvarial growth and development. Surveillance data suggests maternal thyroid disorders (hyperthyroidism, hypothyroidism with pharmacological replacement, and Maternal Graves Disease) are linked to as much as a 2.5 fold increased risk for craniosynostosis. Craniosynostosis is the premature fusion of one or more calvarial growth sites (sutures) prior to the completion of brain expansion. Thyroid hormones maintain proper bone mineral densities by interacting with growth hormone and aiding in the regulation of insulin like growth factors (IGFs). Disruption of this hormonal control of bone physiology may lead to altered bone dynamics thereby increasing the risk for craniosynostosis. In order to elucidate the effect of exogenous thyroxine exposure on cranial suture growth and morphology, wild type C57BL6 mouse litters were exposed to thyroxine in utero (control = no treatment; low ~167 ng per day; high ~667 ng per day). Thyroxine exposed mice demonstrated craniofacial dysmorphology (brachycranic). High dose exposed mice showed diminished area of the coronal and widening of the sagittal sutures indicative of premature fusion and compensatory growth. Presence of thyroid receptors was confirmed for the murine cranial suture and markers of proliferation and osteogenesis were increased in sutures from exposed mice. Increased Htra1 and Igf1 gene expression were found in sutures from high dose exposed individuals. Pathways related to the HTRA1/IGF axis, specifically Akt and Wnt, demonstrated evidence of increased activity. Overall our data suggest that maternal exogenous thyroxine exposure can drive calvarial growth alterations and altered suture morphology.

The structures of passivated layers on the single crystals of austenitic steels

International Nuclear Information System (INIS)

Glownia, J.; Banas, J.

1995-01-01

In this work, the conditions of passivation and structure of passive layers on the single crystals in Fe-Cr18-Ni9 alloys are presented. The data shown the differences in the rate of passivation and in stability of passive layers on the (001), (011) and (111) surfaces. The passive layers are composed with the mixture of Fe +2 and Cr +3 oxides and hydroxides. On the (001) surface, the depth of passive layer is greater than on the (111) surface. (author)

Single-layer skull approximations perform well in transcranial direct current stimulation modeling

NARCIS (Netherlands)

Rampersad, S.M.; Stegeman, D.F.; Oostendorp, T.F.

2013-01-01

In modeling the effect of transcranial direct current stimulation, the representation of the skull is an important factor. In a spherical model, we compared a realistic skull modeling approach, in which the skull consisted of three isotropic layers, to anisotropic and isotropic single-layer

Single-layer closure of typhoid enteric perforation: Our experience ...

African Journals Online (AJOL)

Materials and Methods: We retrospectively studied the effects of single versus double layer intestinal closure after typhoid enteric perforation with peritonitis in 902 pediatric patients from September 2007 to April 2012. All the patients underwent laparotomy after resuscitation and antibiotic cover. The patients were divided ...

Gastric full-thickness suturing during EMR and for treatment of gastric-wall defects (with video).

Science.gov (United States)

von Renteln, Daniel; Schmidt, Arthur; Riecken, Bettina; Caca, Karel

2008-04-01

The endoscopic full-thickness Plicator device was initially developed to provide an endoscopic treatment option for patients with GERD. Because the endoscopic full-thickness Plicator enables rapid and easy placement of transmural sutures, comparable with surgical sutures, we used the Plicator device for endoscopic treatment or prevention of GI-wall defects. To describe the outcomes and complications of endoscopic full-thickness suturing during EMR and for the treatment of gastric-wall defects. A report of 4 cases treated with the endoscopic full-thickness suturing between June 2006 and April 2007. A large tertiary-referral center. Four subjects received endoscopic full-thickness suturing. The subjects were women, with a mean age of 67 years. Of the 4 subjects, 3 received endoscopic full-thickness suturing during or after an EMR. One subject received endoscopic full-thickness suturing for treatment of a fistula. Primary outcome measurements were clinical procedural success and procedure-related adverse events. The mean time for endoscopic full-thickness suturing was 15 minutes. In all cases, GI-wall patency was restored or ensured, and no procedure-related complications occurred. All subjects responded well to endoscopic full-thickness suturing. The resection of one GI stromal tumor was incomplete. Because of the Plicator's 60F distal-end diameter, endoscopic full-thickness suturing could only be performed with the patient under midazolam and propofol sedation. The durable Plicator suture might compromise the endoscopic follow-up after EMR. The endoscopic full-thickness Plicator permits rapid and easy placement of transmural sutures and seems to be a safe and effective alternative to surgical intervention to restore GI-wall defects or to ensure GI-wall patency during EMR procedures.

Transfer-free batch fabrication of single layer graphene transistors.

Science.gov (United States)

Levendorf, Mark P; Ruiz-Vargas, Carlos S; Garg, Shivank; Park, Jiwoong

2009-12-01

Full integration of graphene into conventional device circuitry would require a reproducible large scale graphene synthesis that is compatible with conventional thin film technology. We report the synthesis of large scale single layer graphene directly onto an evaporated copper film. A novel fabrication method was used to directly pattern these graphene sheets into devices by simply removing the underlying copper film. Raman and conductance measurements show that the mechanical and electrical properties of our single layer graphene are uniform over a large area, ( Ferrari, A. C. et al. Phys. Rev. Lett. 2006, 97, 187401.) which leads to a high device yield and successful fabrication of ultra long (>0.5 mm) graphene channels. Our graphene based devices present excellent electrical properties including a promising carrier mobility of 700 cm(2)/V.s and current saturation characteristics similar to devices based on exfoliated graphene ( Meric, I.. et al. Nat Nanotechnol. 2008, 3, 654-659).

Biomechanical comparison of 4 double-row suture-bridging rotator cuff repair techniques using different medial-row configurations.

Science.gov (United States)

Pauly, Stephan; Kieser, Bettina; Schill, Alexander; Gerhardt, Christian; Scheibel, Markus

2010-10-01

Biomechanical comparison of different suture-bridge configurations of the medial row with respect to initial construct stability (time 0, porcine model). In 40 porcine fresh-frozen shoulders, the infraspinatus tendons were dissected from their insertions. All specimens were operated on by use of the suture-bridge technique, only differing in terms of the medial-row suture-grasping configuration, and randomized into 4 groups: (1) single-mattress (SM) technique, (2) double-mattress (DM) technique, (3) cross-stitch (CS) technique, and (4) double-pulley (DP) technique. Identical suture anchors were used for all specimens (medial: Bio-Corkscrew FT 5.5 [Arthrex, Naples, FL]; lateral: Bio-PushLock 3.5 [Arthrex]). All repairs were cyclically loaded from 10 to 60 N until 10 to 200 N (20-N stepwise increase after 50 cycles each) with a material testing machine. Forces at 3 and 5 mm of gap formation, mode of failure, and maximum load to failure were recorded. The DM technique had the highest ultimate tensile strength (368.6 ± 99.5 N) compared with the DP (248.4 ± 122.7 N), SM (204.3 ± 90 N), and CS (184.9 ± 63.8 N) techniques (P = .004). The DM technique provided maximal force resistance until 3 and 5 mm of gap formation (90.0 ± 18.1 N and 128.0 ± 32.3 N, respectively) compared with the CS (72 ± 8.9 N and 108 ± 20.2 N, respectively), SM (66.0 ± 8.9 N and 90.0 ± 26.9 N, respectively), and DP (62.2 ± 6.2 N and 71 ± 13.2 N, respectively) techniques (P biomechanical construct stability at time 0 in this porcine ex vivo model. This technique increases initial stability and resistance to suture cutting through the rotator cuff tendon after arthroscopic suture-bridge repair. Copyright © 2010 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Rapid growth of single-layer graphene on the insulating substrates by thermal CVD

Energy Technology Data Exchange (ETDEWEB)

Chen, C.Y. [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Dai, D.; Chen, G.X.; Yu, J.H. [Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Nishimura, K. [Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Advanced Nano-processing Engineering Lab, Mechanical Systems Engineering, Kogakuin University (Japan); Lin, C.-T. [Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Jiang, N., E-mail: jiangnan@nimte.ac.cn [Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Zhan, Z.L., E-mail: zl_zhan@sohu.com [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093 (China)

2015-08-15

Highlights: • A rapid thermal CVD process has been developed to directly grow graphene on the insulating substrates. • The treating time consumed is ≈25% compared to conventional CVD procedure. • Single-layer and few-layer graphene can be formed on quartz and SiO{sub 2}/Si substrates, respectively. • The formation of thinner graphene at the interface is due to the fast precipitation rate of carbon atoms during cooling. - Abstract: The advance of CVD technique to directly grow graphene on the insulating substrates is particularly significant for further device fabrication. As graphene is catalytically grown on metal foils, the degradation of the sample properties is unavoidable during transfer of graphene on the dielectric layer. Moreover, shortening the treatment time as possible, while achieving single-layer growth of graphene, is worthy to be investigated for promoting the efficiency of mass production. Here we performed a rapid heating/cooling process to grow graphene films directly on the insulating substrates by thermal CVD. The treating time consumed is ≈25% compared to conventional CVD procedure. In addition, we found that high-quality, single-layer graphene can be formed on quartz, but on SiO{sub 2}/Si substrate only few-layer graphene can be obtained. The pronounced substrate effect is attributed to the different dewetting behavior of Ni films on the both substrates at 950 °C.

Comparison of surgical time and complication rate of subcutaneous and skin closure using barbed suture or traditional knotted suture in dogs.

Science.gov (United States)

Nutt, Laura K; Wilson, Megan L; Sakals, Sherisse

2017-12-01

This prospective study evaluated the handling, intraoperative and postoperative complication rates of a barbed knotless suture for closure of subcutaneous tissue and skin in 17 client-owned dogs (group A) following a tibial plateau leveling osteotomy procedure. Clinical characteristics, surgical time, and complication rates were compared to a control group of 17 client-owned dogs (group B) with subcutaneous tissue and skin closure using traditional suture material. Signalment was not significantly different between groups and did not have an effect on complication rates. Surgical times were not significantly different for subcutaneous tissue or skin closure between the 2 groups. There were significantly more intraoperative complications in the barbed suture group (A: 4/17; B: 0/17; P = 0.033) but no difference in minor or major postoperative complication rates (minor A: 2/16; B: 1/14; P = 0.626, major A: 2/16; B: 0/14; P = 0.171).

Introduction of a potent single-donor fibrin glue for vascular anastomosis: An animal study

Directory of Open Access Journals (Sweden)

Mehdi Rasti Ardakani

2012-01-01

Full Text Available Background: Vascular anastomosis is considered as a difficult surgical procedure. Although different alternative methods have been tried to tackle these difficulties, none were found to be successful. Commercial fibrin glue has recently been used for vascular anastomosis. However, it did not gain popularity due to some limitations such as low tensile strength, rapid removal by the immune system, and risk of transmission of blood-borne viral infections. In this article, we presented a novel method for producing single-donor human fibrin glue and determined its success rate for vascular anastomosis in an animal model. Materials ans Methods : In this study, 3 mL of single-donor fibrin sealant was prepared from 150 mL of whole blood containing 50-70 mg/mL of fibrinogen. The study was performed on 10 dogs and 5 cats. After transection of the carotid artery, both ends were anastomosed by means of 3-4 sutures (Prolene 8-0. The suture line was then sealed with one layer of the new fibrin sealant. After 3-8 weeks, the site of anastomosis was evaluated angiographically and morphologically for healing and possible complications such as thrombosis or aneurysm. Results: In evaluations 3 weeks after the surgery, all arterial anastomoses were patent in dogs, but some degree of subintimal hyperplasia was noted. After 8 weeks, all anastomoses were patent and the degree of subintimal hyperplasia was decreased. In cats on the other hand, after 4 weeks, all anastomoses were patent and subintimal hyperplasia was absent. Conclusions: Single-donor fibrin glue was a quite reliable and practical alternative to minimize suturing and therefore operative time in our animal model. This sealant can easily be obtained from the patient′s whole blood. Its application in humans would require further studies.

Ureteroscopic holmium laser cutting for inadvertently sutured drainage tube (report of five cases).

Science.gov (United States)

Gao, Xu; Lu, Xin; Ren, Shancheng; Xu, Chuanliang; Sun, Yinghao

2008-07-01

The aim of this paper is to report a simple solution for inadvertently sutured drainage tube after urological surgery and discuss the different managements according to different types of this embarrassing complication. From September 2001 to January 2007, five inadvertently sutured drainage tubes were treated with ureteroscopic holmium laser cutting for the suture. All drainage tubes were removed after the operation without other complications. Holmium laser cutting via ureteroscope is a simple solution for the embarrassing problem of inadvertently sutured drainage tube. It can save the patient from undergoing another open surgery.

SUTURE NON-SUTSRE CIRCUMFERENTIAL REPAIR OF CAROTID ARTERY

Directory of Open Access Journals (Sweden)

Jafar Nader

1969-01-01

Full Text Available plastic adhesives, normal butyl cyanoacrylate monomer, isobutyl cyanoacrylate monomer and methyl 2 _ cyaooacrylate monomer, have been utilized in a comparative study with 5-{ silk suture in the repair of transected carotid arteries. Follow _ up arteriog ramS indicate isobutyl cyanoacrylate monomer and normal butyl cyanoacrylate monomer as having the most impressive rerults with only tWO thrombosis each. The silk suture had three thromboses and the adhesive methyl 2 _ cyanoacrylate monomer had nine, one of which a delayed

Caudal Septal Stabilization Suturing Technique to Treat Crooked Noses.

Science.gov (United States)

Baykal, Bahadir; Erdim, Ibrahim; Guvey, Ali; Oghan, Fatih; Kayhan, Fatma Tulin

2016-10-01

To rotate the nasal axis and septum to the midline using an L-strut graft and a novel caudal septal stabilization suturing technique to treat crooked noses. Thirty-six patients were included in the study. First, an L-strut graft was prepared by excising the deviated cartilage site in all patients. Second, multiple stabilization suturing, which we describe as a caudal septal stabilization suturing technique with a "fishing net"-like appearance, was applied between the anterior nasal spine and caudal septum in all patients. This new surgical technique, used to rotate the caudal septum, was applied to 22 I-type and 14 C-type crooked noses. Correction rates for the crooked noses were compared between the 2 inclination types with angular estimations. Deviation angles were measured using the AutoCAD 2012 software package and frontal (anterior) views, with the Frankfurt horizontal line parallel to the ground. Nasal axis angles showing angle improvement graded 4 categories as excellent, good, acceptable, and unsuccessful for evaluations at 6 months after surgery in the study. The success rate in the C-type nasal inclination was 86.7% (±21.9) and 88% (±16.7) in the I-type. The overall success rate of L-strut grafting and caudal septal stabilization suturing in crooked nose surgeries was 87.5% (±18.6). "Unsuccessful" results were not reported in any of the patients. L-strut grafting and caudal septal stabilization suturing techniques are efficacious in crooked noses according to objective measurement analysis results. However, a longer follow-up duration in a larger patient population is needed.

Continuous growth of low-temperature Si epitaxial layer with heavy phosphorous and boron doping using photoepitaxy

International Nuclear Information System (INIS)

Yamazaki, T.; Minakata, H.; Ito, T.

1990-01-01

The authors grew p + -n + silicon epitaxial layers, heavily doped with phosphorus and boron, continuously at 650 degrees C using low-temperature photoepitaxy. Then N + photoepitaxial layer with a phosphorus concentration above 10 17 cm -3 grown on p - substrate shows high-density surface pits, and as a result, poor crystal quality. However, when this n + photoepitaxial layer is grown continuously on a heavily boron-doped p + photoepitaxial layer, these surface pits are drastically decreased, disappearing completely above a hole concentration of 10 19 cm -3 in the p + photoepitaxial layer. The phosphorus activation ratio and electron Hall mobility in the heavily phosphorus-doped n + photoexpitaxial layer were also greatly improved. The authors investigated the cause of the surface pitting using a scanning transmission electron microscope, secondary ion mass spectroscopy, and energy-dispersive x-ray spectroscopy. They characterized the precipitation of phosphorus atoms on the crystal surface at the initial stage of the heavily phosphorus-doped n + photoexpitaxial layer growth

A "continuity-index" for assessing ice-sheet dynamics from radar-sounded internal layers

DEFF Research Database (Denmark)

Karlsson, Nanna Bjørnholt; Rippin, David; Bingham, Robert G.

2012-01-01

Radio-echo sounding (RES) of polar icesheets reveals extensive internal layering. The degree of continuity of internal layering holds critical information about the ice-flow field, but previous analyses of this parameter have been limited to qualitative classifications. Here we present a new...... further support that the main trunk and tributaries are unlikely to have undergone substantial migration since the deposition of the internal layering. Significantly, our new method for analyzing internallayers is readily transferable across RES datasets, offering promise for data-led assessments of past...

Effectiveness of ultrasonographic evaluation of the cranial sutures in children with suspected craniosynostosis

International Nuclear Information System (INIS)

Simanovsky, Natalia; Hiller, Nurith; Koplewitz, Benjamin; Rozovsky, Katya

2009-01-01

Computed tomography (CT) is the 'gold standard' for evaluation of the cranial sutures. While prenatal cranial suture evaluation with ultrasound (US) is common, US has not been established as a postnatal screening tool. We evaluated the effectiveness of US for diagnosis of craniosynostosis (CS). During 2006, 24 infants with questionable CS were assessed with US of the sagittal, metopic, and bilateral coronal and lambdoid sutures. US findings and clinical records were reviewed retrospectively. Sixteen boys and eight girls (ages 1-11 months, mean 4.3) underwent US. The correct diagnosis was provided in 23 (95%), with equivocal findings in one patient. Cranial sutures appeared normal in 15 infants, who had normal clinical presentation at mean 5.8 months follow-up; CT confirmation was obtained in two. In eight children, US identified premature closure of one or more cranial sutures. Three-dimensional CT was performed as a preparation for surgery in four, with classical CS findings. In one case with inconclusive US findings, CT showed narrow but open sutures. Sonographic examination of cranial sutures may serve as a first imaging tool for evaluation of craniosynostosis. CT may be reserved for children with abnormal or equivocal ultrasound and for preoperative planning. (orig.)

Effectiveness of ultrasonographic evaluation of the cranial sutures in children with suspected craniosynostosis

Energy Technology Data Exchange (ETDEWEB)

Simanovsky, Natalia; Hiller, Nurith; Koplewitz, Benjamin; Rozovsky, Katya [Hadassah Hebrew University Medical Center, Department of Medical Imaging, Mount, Scopus, P.O. Box 24035, Jerusalem (Israel)

2009-03-15

Computed tomography (CT) is the 'gold standard' for evaluation of the cranial sutures. While prenatal cranial suture evaluation with ultrasound (US) is common, US has not been established as a postnatal screening tool. We evaluated the effectiveness of US for diagnosis of craniosynostosis (CS). During 2006, 24 infants with questionable CS were assessed with US of the sagittal, metopic, and bilateral coronal and lambdoid sutures. US findings and clinical records were reviewed retrospectively. Sixteen boys and eight girls (ages 1-11 months, mean 4.3) underwent US. The correct diagnosis was provided in 23 (95%), with equivocal findings in one patient. Cranial sutures appeared normal in 15 infants, who had normal clinical presentation at mean 5.8 months follow-up; CT confirmation was obtained in two. In eight children, US identified premature closure of one or more cranial sutures. Three-dimensional CT was performed as a preparation for surgery in four, with classical CS findings. In one case with inconclusive US findings, CT showed narrow but open sutures. Sonographic examination of cranial sutures may serve as a first imaging tool for evaluation of craniosynostosis. CT may be reserved for children with abnormal or equivocal ultrasound and for preoperative planning. (orig.)

Antibacterial-Coated Suture in Reducing Surgical Site Infection in Breast Surgery: A Prospective Study

Directory of Open Access Journals (Sweden)

Enora Laas

2012-01-01

Full Text Available Background. To reduce the incidence of microbial colonization of suture material, Triclosan- (TC-coated suture materials have been developed. The aim of this study was to assess the incidence of suture-related complications (SRC in breast surgery with and without the use of TC-coated sutures. Methods. We performed a study on two consecutive periods: 92 patients underwent breast surgery with conventional sutures (Group 1 and 98 with TC-coated sutures (Group 2. We performed subgroups analyses and developed a model to predict SRC in Group 1 and tested its clinical efficacy in Group 2 using a nomogram-based approach. Results. The SRC rates were 13% in Group 1 and 8% in Group 2. We found that some subgroups may benefit from TC-coated sutures. The discrimination obtained from a logistic regression model developed in Group 1 and based on multifocality, age and axillary lymphadenectomy was 0.88 (95% CI 0.77–0.95 (. There was a significant difference in Group 2 between predicted probabilities and observed percentages (. The predicted and observed proportions of complications in the high-risk group were 38% and 13%, respectively. Conclusion. This study used individual predictions of SRC and showed that using TC-coated suture may prevent SRC. This was particularly significant in high-risk patients.

Structural and electronic properties of single molecules and organic layers on surfaces

NARCIS (Netherlands)

Sotthewes, Kai

2016-01-01

Single molecules and organic layers on well-defined solid surfaces have attracted tremendous attention owing to their interesting physical and chemical properties. The ultimate utility of single molecules or self-assembled monolayers (SAMs) for potential applications is critically dependent on the

A simple suture-retrieval device for the placement of u-stitches during laparoscopic gastrostomy.

Science.gov (United States)

Mattei, Peter

2009-02-01

During minimally invasive operations, it is sometimes necessary to retrieve the end of a suture or a suture needle and bring it out through the abdominal wall. Using a standard needle and a length of suture, we have developed a simple device that allows the retrieval of a suture end during minimally invasive operations that require the placement of U-or stay stitches. The author has used the device described during more than 100 laparoscopic gastrostomy placement procedures and other operations involving the placement of U- or stay stitches with excellent results and no complications. Using a beveled hollow-bore needle and a loop of polypropylene suture, one can construct a simple device that allows the retrieval of a suture from within a body cavity during minimally invasive surgery, making the placement of U- and stay stitches easier and more precise.

Influence of suturing material on wound healing: Experimental study in dogs

Directory of Open Access Journals (Sweden)

Gazivoda Dragan

2015-01-01

Full Text Available Background/Aim. The most common materials implanted in the human organism are suture materials that are classified on the basis of several criteria, usually the origin, structure, and properties. The properties of suture materials are related to its absorbability and non-absorbability. When using resorbable materials it is of great importance to determine whether its absorbability and tensile strength help wound healing in function of time. Sutures themselves can become a source of inflammation, that may reduce or compromise the potential of reparation and regeneration. The aim of this experimental study on dogs was to ascertain whether the absorption rate and the degree of local tissue reactions differ from information provided by the manufacturers, whether there are differences between the applied suture materials and which of the used suture materials have better effect on wound healing. Methods. Experimental testing of the selected suture materials basic characteristics was performed on 6 German Shepherd dogs, which, after induction of general anesthesia, were made 3 identical incisions each in all 4 quadrants (left and right side of the upper and lower jaws, so that 12 horizontal incisions were formed, 10 mm long, 20-25 mm distant from one another, on each animal. Randomly, incisions were stitched up in the following order, starting from back to front: catgut, Dexon®, Vicryl-Rapid®. The experiment was terminated by histopathological examination of tissue samples, taken on postoperative day 3, 7, 14 and 21 in order to identify the effect of healing and the degree of local reaction. Results. The obtained results suggest that catgut has the highest absorption rate, while Dexon® the lowest. Vicryl-Rapid® causes the lowest level of local reactions, while Dexon® the highest. Conclusion. There is no ideal suture material because various patient factors also influence the wound healing process.

Thermoelectric Response in Single Quintuple Layer Bi2Te3

KAUST Repository

Sharma, S.; Schwingenschlö gl, Udo

2016-01-01

of single quintuple layer Bi2Te3 by considering both the electron and phonon transport. On the basis of first-principles density functional theory, the electronic and phononic contributions are calculated by solving Boltzmann transport equations

Comparison of ultrasonic shears and traditional suture ligature for vaginal hysterectomy: randomized controlled trial.

Science.gov (United States)

Fitz-Gerald, Alison Louise; Tan, Jason; Chan, Kok-Weng; Polyakov, Alex; Edwards, Geoff N; Najjar, Haider; Tsaltas, Jim; Vollenhoven, Beverley

2013-01-01

To compare operating time, intraoperative blood loss, postoperative analgesia, and length of hospital stay using ultrasonic shears vs traditional suture ligature in vaginal hysterectomy. Randomized controlled trial (Canadian Task Force classification I). Gynecology units within a single health network, university hospital. Forty women requiring vaginal hysterectomy because of benign disease. Vaginal hysterectomy performed using either ultrasonically activated shears (USS) or traditional suture ligatures. Twenty-one patients were randomized to the USS arm, and 19 patients to the traditional suture ligature arm. Patient characteristics were comparable. Mean (SD) hysterectomy time and was similar in both the USS and traditional arms, 28.66 (4.0) minutes vs 32.37 (3.18) minutes (p = .47), as was total operating time, 97.38 (8.9) minutes vs 91.63 (7.69) minutes (p = .63). Operative blood loss was significantly decreased in the USS group: 62.63 (12.46) mL vs 136.05 (21.54) mL (p = .006). There was, however, no significant change in hemoglobin concentration between the 2 groups: 19.53 (1.79) g/L vs -16.72 (2.5) g/L. There was no significant difference in mean oxycodone use: 9.29 (2.66) mg vs 8.06 (3.19) mg (p = .77). Length of hospital stay was similar in both groups: 58.98 (3.27) hours vs 60.05 (6.48) hours (p = .88). There was no significant difference in overall complication rates between the groups. Although the Harmonic scalpel system, compared with the traditional suture ligation method, seems to be a safe alternative for securing the pedicles in vaginal hysterectomy, it offers no benefit insofar as operative time, reduction in clinically significant blood loss, and analgesic requirements. Copyright © 2013 AAGL. Published by Elsevier Inc. All rights reserved.

Persistent Charge-Density-Wave Order in Single-Layer TaSe2.

Science.gov (United States)

Ryu, Hyejin; Chen, Yi; Kim, Heejung; Tsai, Hsin-Zon; Tang, Shujie; Jiang, Juan; Liou, Franklin; Kahn, Salman; Jia, Caihong; Omrani, Arash A; Shim, Ji Hoon; Hussain, Zahid; Shen, Zhi-Xun; Kim, Kyoo; Min, Byung Il; Hwang, Choongyu; Crommie, Michael F; Mo, Sung-Kwan

2018-02-14

We present the electronic characterization of single-layer 1H-TaSe 2 grown by molecular beam epitaxy using a combined angle-resolved photoemission spectroscopy, scanning tunneling microscopy/spectroscopy, and density functional theory calculations. We demonstrate that 3 × 3 charge-density-wave (CDW) order persists despite distinct changes in the low energy electronic structure highlighted by the reduction in the number of bands crossing the Fermi energy and the corresponding modification of Fermi surface topology. Enhanced spin-orbit coupling and lattice distortion in the single-layer play a crucial role in the formation of CDW order. Our findings provide a deeper understanding of the nature of CDW order in the two-dimensional limit.

Diffusion of Supercritical Fluids through Single-Layer Nanoporous Solids: Theory and Molecular Simulations.

Science.gov (United States)

Oulebsir, Fouad; Vermorel, Romain; Galliero, Guillaume

2018-01-16

With the advent of graphene material, membranes based on single-layer nanoporous solids appear as promising devices for fluid separation, be it liquid or gaseous mixtures. The design of such architectured porous materials would greatly benefit from accurate models that can predict their transport and separation properties. More specifically, there is no universal understanding of how parameters such as temperature, fluid loading conditions, or the ratio of the pore size to the fluid molecular diameter influence the permeation process. In this study, we address the problem of pure supercritical fluids diffusing through simplified models of single-layer porous materials. Basically, we investigate a toy model that consists of a single-layer lattice of Lennard-Jones interaction sites with a slit gap of controllable width. We performed extensive equilibrium and biased molecular dynamics simulations to document the physical mechanisms involved at the molecular scale. We propose a general constitutive equation for the diffusional transport coefficient derived from classical statistical mechanics and kinetic theory, which can be further simplified in the ideal gas limit. This transport coefficient relates the molecular flux to the fluid density jump across the single-layer membrane. It is found to be proportional to the accessible surface porosity of the single-layer porous solid and to a thermodynamic factor accounting for the inhomogeneity of the fluid close to the pore entrance. Both quantities directly depend on the potential of mean force that results from molecular interactions between solid and fluid atoms. Comparisons with the simulations data show that the kinetic model captures how narrowing the pore size below the fluid molecular diameter lowers dramatically the value of the transport coefficient. Furthermore, we demonstrate that our general constitutive equation allows for a consistent interpretation of the intricate effects of temperature and fluid loading

High efficiency rubrene based inverted top-emission organic light emitting devices with a mixed single layer

International Nuclear Information System (INIS)

Wang, Zhaokui; Lou, Yanhui; Naka, Shigeki; Okada, Hiroyuki

2010-01-01

Inverted top-emission organic light emitting devices (TEOLEDs) with a mixed single layer by mixing of electron transport materials (PyPySPyPy and Alq 3 ), hole transport material (α-NPD) and dope material (rubrene) were investigated. Maximum power efficiency of 3.5 lm/W and maximum luminance of 7000 cd/m 2 were obtained by optimizing the mixing ratio of PyPySPyPy:Alq 3 :α-NPD:rubrene=25:50:25:1. Luminance and power efficiency of mixed single layer device were two times improved compared to bi-layer heterojunction device and tri-layer heterojunction device. Lifetime test also shows that the mixed single layer device exhibits longer operational lifetimes of 343 h, which is three times longer than the 109 h for tri-layer device, and two times longer than the 158 h for bi-layer device. In addition, the maximum luminance and power efficiency were obtained at 20,000 cd/m 2 and 7.5 lm/W, respectively, when a TPD layer of 45 nm was capped onto the top metal electrode.

Thermoelectric Response in Single Quintuple Layer Bi2Te3

KAUST Repository

Sharma, S.

2016-10-05

Because Bi2Te3 belongs to the most important thermoelectric materials, the successful exfoliation of a single quintuple layer has opened access to an interesting two-dimensional material. For this reason, we study the thermoelectric properties of single quintuple layer Bi2Te3 by considering both the electron and phonon transport. On the basis of first-principles density functional theory, the electronic and phononic contributions are calculated by solving Boltzmann transport equations. The dependence of the lattice thermal conductivity on the phonon mean free path is evaluated along with the contributions of the acoustic and optical branches. We find that the thermoelectric response is significantly better for p- than for n-doping. By optimizing the carrier concentration, at 300 K, a ZT value of 0.77 is achieved, which increases to 2.42 at 700 K.

Knotless double-row SutureBridge rotator cuff repairs have improved self-reinforcement compared with double-row SutureBridge repairs with tied medial knots: a biomechanical study using an ovine model.

Science.gov (United States)

Smith, Geoffrey C S; Bouwmeester, Theresia M; Lam, Patrick H

2017-12-01

In double-row SutureBridge (Arthrex, Naples, FL, USA) rotator cuff repairs, increasing tendon load may generate progressively greater compression forces at the repair footprint (self-reinforcement). SutureBridge rotator cuff repairs using tied horizontal mattress sutures medially may limit this effect compared with a knotless construct. Rotator cuff repairs were performed in 9 pairs of ovine shoulders. One group underwent repair with a double-row SutureBridge construct with tied horizontal medial-row mattress sutures. The other group underwent repair in an identical fashion except that medial-row knots were not tied. Footprint contact pressure was measured at 0° and 20° of abduction under loads of 0 to 60 N. Pull-to-failure tests were then performed. In both repair constructs, each 10-N increase in rotator cuff tensile load led to a significant increase in footprint contact pressure (P row SutureBridge configuration, self-reinforcement is seen in repairs with and without medial-row knots. Self-reinforcement is greater with the knotless technique. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Feasibility of X-ray analysis of multi-layer thin films at a single beam voltage

International Nuclear Information System (INIS)

Statham, P J

2010-01-01

Multi-layer analysis using electron beam excitation and X-ray spectrometry is a powerful tool for characterising layers down to 1 nm thickness and with typically 1 μm lateral resolution but does not always work. Most published applications have used WDS with many measurements at different beam voltages and considerable experience has been needed to choose lines and voltages particularly for complex multi-layer problems. A new objective mathematical approach is described which demonstrates whether X-ray analysis can obtain reliable results for an arbitrary multi-layer problem. A new algorithm embodied in 'ThinFilmID' software produces a single plot that shows feasibility of achieving results with a single EDS spectrum and suggests the optimal beam voltage. Synthesis of EDS spectra allows the precision in results to be estimated and acquisition conditions modified before wasting valuable instrument time. Thus, practicality of multi-layer thin film analysis at a single beam voltage can now be established without the extensive experimentation that was previously required by a microanalysis expert. Examples are shown where the algorithm discovers viable single-voltage conditions for applications that experts previously thought could only be addressed using measurements at more than one beam voltage.

Extrusion of bone anchor suture following flexor digitorum profundus tendon avulsion injury repair.

LENUS (Irish Health Repository)

Tiong, William H C

2011-09-01

Flexor digitorum profundus (FDP) zone I tendon avulsion injury is traditionally repaired with a pullout suture technique. More recently, bone anchor sutures have been used as a viable alternative and have largely replaced areas in hand surgery where pullout suture technique was once required. To date, there have been very few complications reported related to bone anchor suture use in FDP tendon reattachment to the bone. We report a very unusual case of extrusion of bone anchor through the nailbed, 6 years after zone I FDP tendon avulsion injury repair and a brief review of literature.

Single-particle thermal diffusion of charged colloids: Double-layer theory in a temperature gradient

NARCIS (Netherlands)

Dhont, J.K.G.; Briels, Willem J.

2008-01-01

The double-layer contribution to the single-particle thermal diffusion coefficient of charged, spherical colloids with arbitrary double-layer thickness is calculated and compared to experiments. The calculation is based on an extension of the Debye-Hückel theory for the double-layer structure that

Self-tapping ability of carbon fibre reinforced polyetheretherketone suture anchors.

Science.gov (United States)

Feerick, Emer M; Wilson, Joanne; Jarman-Smith, Marcus; Ó'Brádaigh, Conchur M; McGarry, J Patrick

2014-10-01

An experimental and computational investigation of the self-tapping ability of carbon fibre reinforced polyetheretherketone (CFR-PEEK) has been conducted. Six CFR-PEEK suture anchor designs were investigated using PEEK-OPTIMA® Reinforced, a medical grade of CFR-PEEK. Experimental tests were conducted to investigate the maximum axial force and torque required for self-taping insertion of each anchor design. Additional experimental tests were conducted for some anchor designs using pilot holes. Computational simulations were conducted to determine the maximum stress in each anchor design at various stages of insertion. Simulations also were performed to investigate the effect of wall thickness in the anchor head. The maximum axial force required to insert a self-tapping CFR-PEEK suture anchor did not exceed 150 N for any anchor design. The maximum torque required to insert a self-tapping CFR-PEEK suture anchor did not exceed 0.8 Nm. Computational simulations reveal significant stress concentrations in the region of the anchor tip, demonstrating that a re-design of the tip geometry should be performed to avoid fracture during self-tapping, as observed in the experimental component of this study. This study demonstrates the ability of PEEK-OPTIMA Reinforced suture anchors to self-tap polyurethane foam bone analogue. This provides motivation to further investigate the self-tapping ability of CFR-PEEK suture anchors in animal/cadaveric bone. An optimised design for CFR-PEEK suture anchors offers the advantages of radiolucency, and mechanical properties similar to bone with the ability to self-tap. This may have positive implications for reducing surgery times and the associated costs with the procedure. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Sutures coated with antiseptic pomade to prevent bacterial colonization: a randomized clinical trial.

Science.gov (United States)

Cruz, Fernando; Leite, Fabiola; Cruz, Gustavo; Cruz, Silvia; Reis, Juarez; Pierce, Matthew; Cruz, Mauro

2013-08-01

The aim of this study was to assess if an antiseptic pomade could reduce the bacterial colonization on multifilament sutures. A randomized clinical trial was conducted with 40 volunteer patients of both sexes aged 18-70, randomly separated into experimental (n = 20) and control (n = 20) groups. The experimental group received pomade-coated sutures (iodoform + calendula) and the control group uncoated sutures. Two millimeters of the suture was harvested from each patient from the 1st to the 15th postoperative day. The bacteria that had adhered to them were cultured. The number of colony-forming units per milliliter (CFU/mL) was determined and the groups were compared using the Mann-Whitney statistical test (P antiseptic pomade was effective in reducing bacterial colonization on silk braided sutures. Copyright © 2013 Elsevier Inc. All rights reserved.

Composite Beam Cross-Section Analysis by a Single High-Order Element Layer

DEFF Research Database (Denmark)

Couturier, Philippe; Krenk, Steen

2015-01-01

An analysis procedure of general cross-section properties is presented. The formulation is based on the stress-strain states in the classic six equilibrium modes of a beam by considering a finite thickness slice modelled by a single layer of 3D finite elements. The theory is illustrated by applic......An analysis procedure of general cross-section properties is presented. The formulation is based on the stress-strain states in the classic six equilibrium modes of a beam by considering a finite thickness slice modelled by a single layer of 3D finite elements. The theory is illustrated...

Pressure estimation from single-snapshot tomographic PIV in a turbulent boundary layer

NARCIS (Netherlands)

Schneiders, J.F.G.; Pröbsting, S.; Dwight, R.P.; Van Oudheusden, B.W.; Scarano, F.

2016-01-01

A method is proposed to determine the instantaneous pressure field from a single tomographic PIV velocity snapshot and is applied to a flat-plate turbulent boundary layer. The main concept behind the single-snapshot pressure evaluation method is to approximate the flow acceleration using the

Mid-Infrared Continuously Tunable Single Mode VECSEL

Science.gov (United States)

Khiar, A.; Rahim, M.; Felder, F.; Fill, M.; Zogg, H.

2011-12-01

Tunable mid-infrared vertical external cavity surface emitting lasers were developed for the wavelength range around 3.8-3.9 μm and 3.2-3.3 μm, respectively. The devices are based on lead salt materials epitaxially grown by MBE on a Si substrate. The active part consists of PbSe QW in a PbSrSe host layer. Both devices are operated around -20 °C and have output power of several 10 mW. By changing the cavity length, a single mode hop free tuning range up to 80 cm-1 is achieved.

Normal Development of Sutures and synchondroses in the central skull base : CT study

International Nuclear Information System (INIS)

Roh, Hong Gee; Kim, Hyung Jin; Kang, Jee Hee; Lee, Kyung Hee; Lim, Myung Kwan; Cho, Young Kuk; Ok, Cheol Su; Suh, Chang Hae

2000-01-01

To evaluate the developmental patterns of the sutures and synchondroses in the central skull base. We evaluated the CT scans of 109 children (age range 29 days to 15 years) with no skull base abnormality who had undergone axial CT of the skull base with 1-mm collimation. Using a five-tier scheme, we analyzed the developmental patterns of the 18 sutures and synchondroses related to the sphenoid and occipital bones. Fusion of the sutures and synchondroses related to the sphenoid bone progressed rapidly during the first two years. Thereafter, changes in the sphenoid bone were dominated by pneumatization of the sphenoid sinus. Fusion of the synchondroses within the sphenoid body, including intersphenoidal, intrapresphenoidal, intrapostsphenoidal synchondrosis occurred early and in most cases was graded ≥3D4. Fusion of the sphenosquamosal, sphenoethmoidal, and frontosphenoidal sutures was delayed, and residual sclerosis was a common finding. Except for Kerckring-supraoccipital synchondrosis, fusion of the six sutures and synchondroses related to the occipital bone occurred more gradually than that of those related to the sphenoid bone. Among these, fusion of the occipitomastoidal suture and petro-occipital synchondrosis was the last to occur. A knowledge of the developmental patterns of sutures and synchondroses can help differentiate normal conditions from those such as fracture, osseous dysplasia, or congenital malformation, which are abnormal. Our results provide certain basic information about skull base maturity in children. (author)

Magneto-transport in the zero-energy Landau level of single-layer and bilayer graphene

International Nuclear Information System (INIS)

Zeitler, U; Giesbers, A J M; Elferen, H J van; Kurganova, E V; McCollam, A; Maan, J C

2011-01-01

We present recent low-temperature magnetotransport experiments on single-layer and bilayer graphene in high magnetic field up to 33 T. In single layer graphene the fourfold degeneracy of the zero-energy Landau level is lifted by a gap opening at filling factor ν = 0. In bilayer graphene, we observe a partial lifting of the degeneracy of the eightfold degenerate zero-energy Landau level.

Timing of ectocranial suture activity in Gorilla gorilla as related to cranial volume and dental eruption.

Science.gov (United States)

Cray, James; Cooper, Gregory M; Mooney, Mark P; Siegel, Michael I

2011-05-01

Research has shown that Pan and Homo have similar ectocranial suture synostosis patterns and a similar suture ontogeny (relative timing of suture fusion during the species ontogeny). This ontogeny includes patency during and after neurocranial expansion with a delayed bony response associated with adaptation to biomechanical forces generated by mastication. Here we investigate these relationships for Gorilla by examining the association among ectocranial suture morphology, cranial volume (as a proxy for neurocranial expansion) and dental development (as a proxy for the length of time that it has been masticating hard foods and exerting such strains on the cranial vault) in a large sample of Gorilla gorilla skulls. Two-hundred and fifty-five Gorilla gorilla skulls were examined for ectocranial suture closure status, cranial volume and dental eruption. Regression models were calculated for cranial volumes by suture activity, and Kendall's tau (a non-parametric measure of association) was calculated for dental eruption status by suture activity. Results suggest that, as reported for Pan and Homo, neurocranial expansion precedes suture synostosis activity. Here, Gorilla was shown to have a strong relationship between dental development and suture activity (synostosis). These data are suggestive of suture fusion extending further into ontogeny than brain expansion, similar to Homo and Pan. This finding allows for the possibility that masticatory forces influence ectocranial suture morphology. © 2011 The Authors. Journal of Anatomy © 2011 Anatomical Society of Great Britain and Ireland.

Effects of diode laser welding with dye-enhanced glue on tensile strength of sutures commonly used in urology.

Science.gov (United States)

Kirsch, A J; Chang, D T; Kayton, M L; Libutti, S K; Connor, J P; Hensle, T W

1996-01-01

Tissue welding using laser-activated protein solders may soon become an alternative to sutured tissue approximation. In most cases, approximating sutures are used both to align tissue edges and provide added tensile strength. Collateral thermal injury, however, may cause disruption of tissue alignment and weaken the tensile strength of sutures. The objective of this study was to evaluate the effect of laser welding on the tensile strength of suture materials used in urologic surgery. Eleven types of sutures were exposed to diode laser energy (power density = 15.9 W/cm2) for 10, 30, and 60 seconds. Each suture was compared with and without the addition of dye-enhanced albumin-based solder. After exposure, each suture material was strained (2"/min) until ultimate breakage on a tensometer and compared to untreated sutures using ANOVA. The strength of undyed sutures were not significantly affected; however, violet and green-dyed sutures were in general weakened by laser exposure in the presence of dye-enhanced glue. Laser activation of the smallest caliber, dyed sutures (7-0) in the presence of glue caused the most significant loss of tensile strength of all sutures tested. These results indicate that the thermal effects of laser welding using our technique decrease the tensile strength of dyed sutures. A thermally resistant suture material (undyed or clear) may prevent disruption of wounds closed by laser welding techniques.

Comparison of Subcuticular Suture Materials in Cesarean Skin Closure

Directory of Open Access Journals (Sweden)

Pınar Solmaz Hasdemir

2015-01-01

Full Text Available Aim. Comparison of the rate of wound complications, pain, and patient satisfaction based on used subcuticular suture material. Methods. A total of 250 consecutive women undergoing primary and repeat cesarean section with low transverse incision were prospectively included. The primary outcome was wound complication rate including infection, dehiscence, hematoma, and hypertrophic scar formation within a 6-week period after operation. Secondary outcomes were skin closure time, the need for use of additional analgesic agent, pain score on numeric rating scale, cosmetic score, and patient scar satisfaction scale. Results. Absorbable polyglactin was used in 108 patients and nonabsorbable polypropylene was used in 142 patients. Wound complication rates were similar in primary and repeat cesarean groups based on the type of suture material. Skin closure time is longer in nonabsorbable suture material group in both primary and repeat cesarean groups. There was no difference between groups in terms of postoperative pain, need for additional analgesic use, late phase pain, and itching at the scar. Although the cosmetic results tended to be better in the nonabsorbable group in primary surgery patients, there was no significant difference in the visual satisfaction of the patients. Conclusions. Absorbable and nonabsorbable suture materials are comparable in cesarean section operation skin closure.

[Comparative study of intestinal anastomosis with manual suture and biofragmentable ring in dogs under corticosteroid administration].

Science.gov (United States)

Fernandes, L C; Matos, D; Novelli, M D; Kim, S B

2000-01-01

This study analyzed intestinal anastomoses by manual suture and by compression with biofragmentable ring under delay of cicatrization administering parenteral corticoids. Twenty dogs were divided into two groups: control and test, the latter submitted to intramuscular administration of hydrocortisone hemisuccinate, 25 to 33 mg/kg/day, on the 30th preoperative and 7th postoperative days. During surgery, each animal underwent two colon sections with anastomosis by manual suture in a single extramucous plane and compression with biofragmentable ring. The animals were sacrificed 7 days after the procedure to evaluate the anastomoses. In the postoperative period, one death occurred in the test group and two in the control group, caused by nonblocked fistula in the anastomoses by ring compression. Statistically, there was a similar incidence of adherences, fistulas, afferent dilatation and obstruction using comparison methods. On microscopy, deficiency in mucous regeneration of the anastomoses by compression was observed. Computerized histological analysis evidenced in the anastomoses by compression, a greater inflammatory reaction, greater edema of the submucous membrane and enlarged scars. It was concluded that, with the biofragmentable ring, in colonic anastomosis under delay of cicatrization induced by corticoids, similar results to manual suture regarding to postoperative complications incidence were obtained; ring, however, determined worse mucous regeneration and greater cicatricial inflammatory reaction.

Tunneling spin injection into single layer graphene.

Science.gov (United States)

Han, Wei; Pi, K; McCreary, K M; Li, Yan; Wong, Jared J I; Swartz, A G; Kawakami, R K

2010-10-15

We achieve tunneling spin injection from Co into single layer graphene (SLG) using TiO₂ seeded MgO barriers. A nonlocal magnetoresistance (ΔR(NL)) of 130  Ω is observed at room temperature, which is the largest value observed in any material. Investigating ΔR(NL) vs SLG conductivity from the transparent to the tunneling contact regimes demonstrates the contrasting behaviors predicted by the drift-diffusion theory of spin transport. Furthermore, tunnel barriers reduce the contact-induced spin relaxation and are therefore important for future investigations of spin relaxation in graphene.

Application of evolution strategy algorithm for optimization of a single-layer sound absorber

Directory of Open Access Journals (Sweden)

Morteza Gholamipoor

2014-12-01

Full Text Available Depending on different design parameters and limitations, optimization of sound absorbers has always been a challenge in the field of acoustic engineering. Various methods of optimization have evolved in the past decades with innovative method of evolution strategy gaining more attention in the recent years. Based on their simplicity and straightforward mathematical representations, single-layer absorbers have been widely used in both engineering and industrial applications and an optimized design for these absorbers has become vital. In the present study, the method of evolution strategy algorithm is used for optimization of a single-layer absorber at both a particular frequency and an arbitrary frequency band. Results of the optimization have been compared against different methods of genetic algorithm and penalty functions which are proved to be favorable in both effectiveness and accuracy. Finally, a single-layer absorber is optimized in a desired range of frequencies that is the main goal of an industrial and engineering optimization process.

Mesozoic and Cenozoic tectonics of the eastern and central Alaska Range: Progressive basin development and deformation in a suture zone

Energy Technology Data Exchange (ETDEWEB)

Ridgway, K.D.; Trop, J.M.; Nokleberg, W.J.; Davidson, C.M.; Eastham, K.R. [Purdue University, W. Lafayette, IN (United States). Dept. of Earth & Atmospheric Science

2002-07-01

Analysis of late Mesozoic and Cenozoic sedimentary basins, metamorphic rocks, and major faults in the eastern and central Alaska Range documents the progressive development of a suture zone that formed as a result of collision of an island-arc assemblage (the Wrangellia composite terrane) with the former North American continental margin. New basin-analysis, structural, and geochronologic data indicate the following stages in the development of the suture zone: (1) Deposition of 3-5 km of Upper Jurassic-Upper Cretaceous marine strata (the Kahiltna assemblage) recorded the initial collision of the island-arc assemblage with the continental margin. (2) Metamorphism of submarine-fan deposits of the Kahiltna basin, located near the leading edge of the island-arc assemblage, occurred at ca. 74 Ma, as determined from a new U-Pb zircon age for a synkinematic sill. (3) Shortening and exhumation of the suture zone peaked from 65 to 60 Ma on the basis of metamorphic and geochronologic data. (4) From 60 to 54 Ma, about 3 km of volcanic strata were deposited over deformed sedimentary strata of the Cantwell basin, and several granitic plutons (the McKinley sequence) were emplaced along the suture zone. (5) Following igneous activity, strike-slip displacement occurred from ca. 54 to 24 Ma along the Denali fault system, which had developed in the existing suture zone. (6) Regional transpressive shortening characterized the suture zone from ca. 24 Ma to the present. Regional subsidence resulted in Miocene coal seams up to 20 m thick and well-developed lacustrine deposits. Overlying the Miocene deposits are about 1.2 km of Pliocene and Holocene conglomeratic deposits. These mapping relationships provide evidence that regional shortening continues to the present in the eastern and central Alaska Range.

Virtual suturing simulation based on commodity physics engine for medical learning.

Science.gov (United States)

Choi, Kup-Sze; Chan, Sze-Ho; Pang, Wai-Man

2012-06-01

Development of virtual-reality medical applications is usually a complicated and labour intensive task. This paper explores the feasibility of using commodity physics engine to develop a suturing simulator prototype for manual skills training in the fields of nursing and medicine, so as to enjoy the benefits of rapid development and hardware-accelerated computation. In the prototype, spring-connected boxes of finite dimension are used to simulate soft tissues, whereas needle and thread are modelled with chained segments. Spherical joints are used to simulate suture's flexibility and to facilitate thread cutting. An algorithm is developed to simulate needle insertion and thread advancement through the tissue. Two-handed manipulations and force feedback are enabled with two haptic devices. Experiments on the closure of a wound show that the prototype is able to simulate suturing procedures at interactive rates. The simulator is also used to study a curvature-adaptive suture modelling technique. Issues and limitations of the proposed approach and future development are discussed.

Comparison of Suture-Based Anchors and Traditional Bioabsorbable Anchors in Foot and Ankle Surgery.

Science.gov (United States)

Hembree, W Chad; Tsai, Michael A; Parks, Brent G; Miller, Stuart D

We compared the pullout strength of a suture-based anchor versus a bioabsorbable anchor in the distal fibula and calcaneus and evaluated the relationship between bone mineral density and peak load to failure. Eight paired cadaveric specimens underwent a modified Broström procedure and Achilles tendon reattachment. The fibula and calcaneus in the paired specimens received either a suture-based anchor or a bioabsorbable suture anchor. The fibular and calcaneal specimens were loaded to failure, defined as a substantial decrease in the applied load or pullout from the bone. In the fibula, the peak load to failure was significantly greater with the suture-based versus the bioabsorbable anchors (133.3 ± 41.8 N versus 76.8 ± 35.3 N; p = .002). No significant difference in load with 5 mm of displacement was found between the 2 groups. In the calcaneus, no difference in the peak load to failure was found between the 2 groups, and the peak load to failure with 5 mm of displacement was significantly lower with the suture-based than with the bioabsorbable anchors (52.2 ± 9.8 N versus 75.9 ± 12.4 N; p = .003). Bone mineral density and peak load to failure were significantly correlated in the fibula with the suture-based anchor. An innovative suture-based anchor had a greater peak load to failure compared with a bioabsorbable anchor in the fibula. In the calcaneus, the load at 5 mm of displacement was significantly lower in the suture-based than in the bioabsorbable group. The correlation findings might indicate the need for a cortical bone shelf with the suture-based anchor. Suture-based anchors could be a viable alternative to bioabsorbable anchors for certain foot and ankle procedures. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Study on electrical defects level in single layer two-dimensional Ta2O5

Science.gov (United States)

Dahai, Li; Xiongfei, Song; Linfeng, Hu; Ziyi, Wang; Rongjun, Zhang; Liangyao, Chen; David, Wei Zhang; Peng, Zhou

2016-04-01

Two-dimensional atomic-layered material is a recent research focus, and single layer Ta2O5 used as gate dielectric in field-effect transistors is obtained via assemblies of Ta2O5 nanosheets. However, the electrical performance is seriously affected by electronic defects existing in Ta2O5. Therefore, spectroscopic ellipsometry is used to calculate the transition energies and corresponding probabilities for two different charged oxygen vacancies, whose existence is revealed by x-ray photoelectron spectroscopy analysis. Spectroscopic ellipsometry fitting also calculates the thickness of single layer Ta2O5, exhibiting good agreement with atomic force microscopy measurement. Nondestructive and noncontact spectroscopic ellipsometry is appropriate for detecting the electrical defects level of single layer Ta2O5. Project supported by the National Natural Science Foundation of China (Grant Nos. 11174058 and 61376093), the Fund from Shanghai Municipal Science and Technology Commission (Grant No. 13QA1400400), the National Science and Technology Major Project, China (Grant No. 2011ZX02707), and the Innovation Program of Shanghai Municipal Education Commission (Grant No. 12ZZ010).

Meniscus suture repair: minimum 10-year outcomes in patients younger than 40 years compared with patients 40 and older.

Science.gov (United States)

Steadman, J Richard; Matheny, Lauren M; Singleton, Steven B; Johnson, Nicholas S; Rodkey, William G; Crespo, Bernardo; Briggs, Karen K

2015-09-01

Few studies have compared outcomes after meniscus suture repair in patients younger than 40 years versus patients 40 years and older. To document failure rates and long-term outcomes after meniscus suture repair by a single surgeon, using the inside-out technique, at a minimum 10-year follow-up in patients younger than 40 years versus those 40 years and older. Cohort study; Level of evidence, 3. This study included all patients 18 years or older who underwent meniscus suture repair with the inside-out technique by a single surgeon between January 1992 and December 2003. Patients were divided into 2 cohorts according to age: meniscus as repaired in the index surgery. Patients completed a subjective questionnaire at minimum of 10 years after arthroscopy. Outcomes measures included Lysholm, Tegner, and patient satisfaction with outcome. All data were collected prospectively. The surgeon performed 339 meniscus repairs between 1992 and 2003. The study included 181 knees in 178 patients, who had a mean age of 33 years (range, 18-70 years). Cohort 1 contained 136 knees; 16 patients (12%) were lost to follow-up and 47 (35%) underwent a subsequent knee arthroscopy. Cohort 2 contained 45 knees; 2 patients (4.4%) were lost to follow-up, 3 patients had a total knee arthroplasty, and 12 patients (28%) underwent a subsequent knee arthroscopy. In cohort 1, the meniscus repair failure rate was 5.5% (6/110), and in cohort 2 it was 5.3% (2/38) (P = .927). There was no significant difference in failure rate based on which meniscus was repaired (P = .257), concomitant anterior cruciate ligament (ACL) reconstruction (P = .092), or microfracture (P = .674). Average follow-up time for cohort 1 was 16.1 years (range, 10.0-21.9 years), with 82% follow-up (n = 73/89); average follow-up time for cohort 2 was 16.2 years (range, 10.1-21.0 years), with 93% follow-up (n = 28/30). There were no significant differences in outcomes scores after meniscus suture repair based on age cohort or meniscus

Double-Row Suture Anchor Repair of Posterolateral Corner Avulsion Fractures.

Science.gov (United States)

Gilmer, Brian B

2017-08-01

Posterolateral corner avulsion fractures are a rare variant of ligamentous knee injury primarily described in the skeletally immature population. Injury is often related to a direct varus moment placed on the knee during sporting activities. Various treatment strategies have been discussed ranging from nonoperative management, to excision of the bony fragment, to primary repair with screws or suture. The described technique is a means for achieving fixation of the bony avulsion using principles familiar to double-row transosseous equivalent rotator cuff repair. Proximal anchors are placed in the epiphysis, and sutures are passed in horizontal mattress fashion. Once tied, the limbs of these same sutures are then passed to more distal anchors. Remaining eyelet sutures can be used to manage peripheral tissue. The final repair provides anatomic reduction and compression of the fragment to its bony bed with minimal extracortical hardware prominence and no violation of the physis. Risks include potential for physeal injury or chondral damage to the lateral femoral condyle through aberrant anchor placement. Postoperative care includes toe-touch weight-bearing restrictions and range of motion restrictions of 0°-90° in a hinged brace for 6 weeks followed by gradual return to activity.

Nonsuturing or Skin Adhesives versus Suturing of the Perineal Skin After Childbirth: A Systematic Review

NARCIS (Netherlands)

Seijmonsbergen-Schermers, A.E.; Sahami, S.; Lucas, C.; de Jonge, A.

2015-01-01

Background: Suturing of perineal trauma after childbirth can cause problems such as pain, discomfort because of tight sutures, the need for suture removal, and dyspareunia. It is unclear whether leaving the perineal skin unsutured or using skin adhesives might prevent these problems. Methods:

Interactive Virtual Suturing Simulations: Enhancement of Student Learning in Veterinary Medicine

Science.gov (United States)

Staton, Amy J.; Boyd, Christine B.

2013-01-01

This capstone addresses an instructional gap in the Morehead State University Veterinary Technology Program and in other similar programs around the globe. Students do not retain the knowledge needed to proficiently complete suture patterns nor do students receive sufficient instructional time during the year to master each suture pattern that is…

The B-Lynch uterine brace suture, and a bit of this and a bit of that...

Science.gov (United States)

Karoshi, Mahantesh

2010-03-01

The widespread application of the B-Lynch brace suture to control postpartum hemorrhage has sparked interest in a variety of adjunctive methods, used alone or in combination, to control uterine bleeding. Although the B-Lynch brace suture has been used with good results throughout the world, failures can and do occur in rare instances, especially when the suture is incorrectly placed for use for an inappropriate indication. Four reports of additional methods to control postpartum hemorrhage are published in this issue of IJGO. Three use the B-Lynch brace suture combined with other techniques. The need for additional techniques reminds the reader of the importance of proper suture application for proper indication. Potential reasons for failure of the B-Lynch suture are provided.

Nickel-Titanium Wire as Suture Material: A New Technique for the Fixation of Skin.

Science.gov (United States)

Li, Haidong; Song, Tao

2018-01-29

To introduce nickel-titanium wire as suture material for closure of incisions in cleft lip procedures. Closure of skin incisions using nickel-titanium wire as suture material, with postoperative follow-up wound evaluation. There was excellent patient satisfaction and good cosmetic outcome. Nickel-titanium wire is an excellent alternative for suture closure of cleft lip surgical incisions.

Critical Anatomy Relative to the Sacral Suture: A Postoperative Imaging Study After Robotic Sacrocolpopexy.

Science.gov (United States)

Crisp, Catrina C; Herfel, Charles V; Pauls, Rachel N; Westermann, Lauren B; Kleeman, Steven D

2016-01-01

This study aimed to characterize pertinent anatomy relative to the sacral suture placed at time of robotic sacrocolpopexy using postoperative computed tomography and magnetic resonance imaging. A vascular clip was placed at the base of the sacral suture at the time of robotic sacrocolpopexy. Six weeks postoperatively, subjects returned for a computed tomography scan and magnetic resonance imaging. Ten subjects completed the study. The middle sacral artery and vein coursed midline or to the left of midline in all the subjects. The left common iliac vein was an average of 26 mm from the sacral suture. To the right of the suture, the right common iliac artery was 18 mm away. Following the right common iliac artery to its bifurcation, the right internal iliac was on average 10 mm from the suture. The bifurcations of the inferior vena cava and the aorta were 33 mm and 54 mm further cephalad, respectively.The right ureter, on average, was 18 mm from the suture. The thickness of the anterior longitudinal ligament was 2 mm.The mean angle of descent of the sacrum was 70 degrees. Lastly, we found that 70% of the time, a vertebral body was directly below the suture; the disc was noted in 30%. We describe critical anatomy surrounding the sacral suture placed during robotic sacrocolpopexy. Proximity of both vascular and urologic structures within 10 to 18 mm, as well as anterior ligament thickness of only 2 mm highlights the importance of adequate exposure, careful dissection, and surgeon expertise.

Corrosion behaviour in saline environments of single-layer titanium and aluminium coatings, and of Ti/Al alternated multi-layers elaborated by a multi-beam PVD technique

International Nuclear Information System (INIS)

Merati, Abdenacer

1994-01-01

This research thesis reports the characterization of anti-corrosion titanium and aluminium coatings deposited on a 35CD4 steel under the form of mono-metallic layers or alternated Ti/Al multi-layers, and obtained by a multibeam PVD technique. The influence of different parameters is studied: single-layer thickness (5, 15 or 30 micro-metres), multi-layer distribution (5 to 6) and substrate (smooth or threaded). Layer nature and microstructure are studied by optical microscopy and scanning electron microscopy (SEM), as well as corrosion toughness in aqueous saline environments. Coated threaded samples have been studied after tightening tests. It appears that titanium layers are denser and more uniform than aluminium layers, and that multi-layer coatings provide a better protection than single-layer coatings. The best behaviour is obtained when titanium is in contact with steel, and aluminium is the outer layer in contact with the corroding environment [fr

Observing the morphology of single-layered embedded silicon nanocrystals by using temperature-stable TEM membranes

Directory of Open Access Journals (Sweden)

Sebastian Gutsch

2015-04-01

Full Text Available We use high-temperature-stable silicon nitride membranes to investigate single layers of silicon nanocrystal ensembles by energy filtered transmission electron microscopy. The silicon nanocrystals are prepared from the precipitation of a silicon-rich oxynitride layer sandwiched between two SiO2 diffusion barriers and subjected to a high-temperature annealing. We find that such single layers are very sensitive to the annealing parameters and may lead to a significant loss of excess silicon. In addition, these ultrathin layers suffer from significant electron beam damage that needs to be minimized in order to image the pristine sample morphology. Finally we demonstrate how the silicon nanocrystal size distribution develops from a broad to a narrow log-normal distribution, when the initial precipitation layer thickness and stoichiometry are below a critical value.

Brief communication: age and fractal dimensions of human sagittal and coronal sutures

DEFF Research Database (Denmark)

Lynnerup, Niels; Jacobsen, Jens Christian Brings

2003-01-01

The fractal dimensions of human sagittal and coronal sutures were calculated on 31 complete skulls from the Terry Collection. The aim was to investigate whether the fractal dimension, relying on the whole sutural length, might yield a better description of age-related changes in sutural morphology......, as opposed to other methods of quantification, which generally rely on more arbitrary scoring systems. However, the fractal dimension did not yield better age correlations than other previously described methods. At best, the results reflected the general observation that young adults below age 40 years...

A simple method to take urethral sutures for neobladder reconstruction and radical prostatectomy

Directory of Open Access Journals (Sweden)

B Satheesan

2007-01-01

Full Text Available For the reconstruction of urethra-vesical anastamosis after radical prostatectomy and for neobladder reconstruction, taking adequate sutures to include the urethral mucosa is vital. Due to the retraction of the urethra and unfriendly pelvis, the process of taking satisfactory urethral sutures may be laborious. Here, we describe a simple method by which we could overcome similar technical problems during surgery using Foley catheter as the guide for the suture.

Nonsuturing or Skin Adhesives versus Suturing of the Perineal Skin After Childbirth: A Systematic Review

NARCIS (Netherlands)

Seijmonsbergen-Schermers, Anna E.; Sahami, Saloomeh; Lucas, Cees; Jonge, Ank de

2015-01-01

Suturing of perineal trauma after childbirth can cause problems such as pain, discomfort because of tight sutures, the need for suture removal, and dyspareunia. It is unclear whether leaving the perineal skin unsutured or using skin adhesives might prevent these problems. CENTRAL, MEDLINE, EMBASE,

A rare case of persistent metopic suture in an elderly individual: Incidental autopsy finding with clinical implications

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S Vikram

2014-01-01

Full Text Available Metopic suture is a dense fibrous joint extending from the nasion to the bregma. Normally, closure of this suture takes place between 1-8 years of age. Failure of this closure beyond 8 years leads to persistent metopic suture. A rare case of persistent metopic suture in a 60-year-old male is documented, who committed suicide by alleged consumption of organophosphorous compound at District Govt. Wenlock Hospital, Mangalore, Karnataka, India. Metopic suture may mimic skull fracture and may mislead an inexperienced forensic expert. Neurosurgeon should also be aware of this anatomical variation while performing frontal craniotomy, as the persistent metopic suture may mimic vertical fracture of the skull. Hence, in this case report, the clinical and medico-legal implications of the persistent metopic sutures have been discussed.

Traction suture modification to tongue-in-groove caudal septoplasty.

Science.gov (United States)

Indeyeva, Y A; Lee, T S; Gordin, E; Chan, D; Ducic, Y

2018-02-01

Caudal septal deviation leads to unfavorable esthetic as well as functional effects on the nasal airway. A modification to the tongue-in-groove (TIG) technique to correct these caudal septal deformities is described. With placement of a temporary suspension suture to the caudal septum, manual traction is applied, assuring that the caudal septum remains in the midline position while it is being secured with multiple through-and-through, trans-columellar and trans-septal sutures. From 2003 to 2016, 148 patients underwent endonasal septoplasty using this modified technique, with excellent functional and cosmetic outcomes and a revision rate of 1.4%. This modified TIG technique replaces the periosteal suture that secures the caudal septum to the midline nasal crest in the original TIG technique. This simplifies the procedure and minimizes the risk of securing the caudal septum off-midline when used in endonasal septoplasty. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Popularity of suture materials among residents and faculty members of a postdoctoral periodontology program.

Science.gov (United States)

Maksoud, Mohamed; Koo, Samuel; Barouch, Kasumi; Karimbux, Nadeem

2014-02-01

The aim of the present study was to determine the favoritism of suture materials among a group of clinicians at a teaching institution. The surveys included 11 absorbable and nine non-absorbable sutures. The surveyor was asked to select his or her suture preferences when it comes to using it in 13 different, commonly-performed surgical procedures. The surveys showed overall preferences for non-absorbable versus absorbable sutures. Chromic Gut with a 4-0 diameter thread reverse cutting FS2 needle was the most favored suture. For periodontal bone grafts and hard tissue ridge augmentation, polytetrafluoroethylene with a 4-0 thread and FS2 needle was preferred. For autogenous gingival grafts, gingival allografts, connective tissue grafts, frenectomy and frenoplasty, Chromic Gut with 5-0 diameter thread reverse cutting P3 needle was favored. For extraction socket preservation, soft tissue canine exposure, ridge augmentation, and dental implants, Chromic Gut with 4-0 diameter thread reverse cutting FS2 needle was preferred, and for sinus augmentation, Vicryl with a 4-0 diameter thread reverse cutting FS2 needle was favored. Absorbable sutures were preferred in the majority of periodontal procedures; however, non-absorbable sutures were favored in procedures that required longer healing or better stability of the flap edges in cases of periodontal and ridge augmentation. © 2013 Wiley Publishing Asia Pty Ltd.

Modeling of 1-D nitrate transport in single layer soils | Dike | Journal ...

African Journals Online (AJOL)

The transport of nitrate in laboratory single soil columns of sand, laterite and clay were investigated after 21 days. The 1-D contaminant transport model by Notodarmojo et al (1991) for single layer soils were calibrated and verified using field data collected from a refuse dump site at avu, owerri, Imo state. The experimental ...

Flexible single-layer ionic organic-inorganic frameworks towards precise nano-size separation

Science.gov (United States)

Yue, Liang; Wang, Shan; Zhou, Ding; Zhang, Hao; Li, Bao; Wu, Lixin

2016-02-01

Consecutive two-dimensional frameworks comprised of molecular or cluster building blocks in large area represent ideal candidates for membranes sieving molecules and nano-objects, but challenges still remain in methodology and practical preparation. Here we exploit a new strategy to build soft single-layer ionic organic-inorganic frameworks via electrostatic interaction without preferential binding direction in water. Upon consideration of steric effect and additional interaction, polyanionic clusters as connection nodes and cationic pseudorotaxanes acting as bridging monomers connect with each other to form a single-layer ionic self-assembled framework with 1.4 nm layer thickness. Such soft supramolecular polymer frameworks possess uniform and adjustable ortho-tetragonal nanoporous structure in pore size of 3.4-4.1 nm and exhibit greatly convenient solution processability. The stable membranes maintaining uniform porous structure demonstrate precisely size-selective separation of semiconductor quantum dots within 0.1 nm of accuracy and may hold promise for practical applications in selective transport, molecular separation and dialysis systems.

Development of a penetration friction apparatus (PFA) to measure the frictional performance of surgical suture

NARCIS (Netherlands)

Zhang, Gangqiang; Ren, Tianhui; Lette, Walter; Zeng, Xiangqiong; van der Heide, Emile

2017-01-01

Nowadays there is a wide variety of surgical sutures available in the market. Surgical sutures have different sizes, structures, materials and coatings, whereas they are being used for various surgeries. The frictional performances of surgical sutures have been found to play a vital role in their

Augmentation of tendon healing with butyric acid-impregnated sutures: biomechanical evaluation in a rabbit model.

Science.gov (United States)

Leek, Bryan T; Tasto, James P; Tibor, Lisa M; Healey, Robert M; Freemont, Anthony; Linn, Michael S; Chase, Derek E; Amiel, David

2012-08-01

Butyric acid (BA) has been shown to be angiogenic and to enhance transcriptional activity in tissue. These properties of BA have the potential to augment biological healing of a repaired tendon. To evaluate this possibility both biomechanically and histologically in an animal tendon repair model. Controlled laboratory study. A rabbit Achilles tendon healing model was used to evaluate the biomechanical strength and histological properties at 6 and 12 weeks after repair. Unilateral tendon defects were created in the middle bundle of the Achilles tendon of each rabbit, which were repaired equivalently with either Ultrabraid BA-impregnated sutures or control Ultrabraid sutures. After 6 weeks, BA-impregnated suture repairs had a significantly increased (P Tendons repaired with BA-impregnated sutures demonstrated improved biomechanical properties at 6 weeks relative to control sutures, suggesting a neoangiogenic mechanism of enhanced healing through an increased myofibroblast presence. These findings demonstrate that a relatively simple alteration of suture material may augment early tendon healing to create a stronger repair construct during this time.

Identification of excitons, trions and biexcitons in single-layer WS{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Plechinger, Gerd; Nagler, Philipp; Kraus, Julia; Paradiso, Nicola; Strunk, Christoph; Schueller, Christian; Korn, Tobias [Institut fuer Experimentelle und Angewandte Physik, Universitaet Regensburg, 93040, Regensburg (Germany)

2015-08-15

Single-layer WS{sub 2} is a direct-gap semiconductor showing strong excitonic photoluminescence features in the visible spectral range. Here, we present temperature-dependent photoluminescence measurements on mechanically exfoliated single-layer WS{sub 2}, revealing the existence of neutral and charged excitons at low temperatures as well as at room temperature. By applying a gate voltage, we can electrically control the ratio of excitons and trions and assert a residual n-type doping of our samples. At high excitation densities and low temperatures, an additional peak at energies below the trion dominates the photoluminescence, which we identify as biexciton emission. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Sutural simplification in Physodoceratinae (Aspidoceratidae, Ammonitina

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Checa, A.

1987-08-01

Full Text Available The estructural analysis of the shell septum interrelationship in sorne Jurassic ammonites allows us to conclude that sutural simplifications occurred throughout the phylogeny, were originated by alterations in the external morphology of the shell. In the case of Physodoceratinae the simplification observed in the morphology of the septal suture may have a double origin. First, an increase in the size of periumbilical tubercles may determine a shallowing of sutural elements and a shortening of saddle and lobe frilling. In other cases, shallowing is determined by a decrease in the whorl expansion rate, an apparent shortening of secondary branching not being observed.El análisis estructural de la interrelación concha-septo en algunos ammonites del Jurásico superior lleva a concluir que las simplificaciones suturales aparecidas a lo largo de la filogenia fueron originadas por alteraciones ocurridas en la morfología externa de la concha. En el caso concreto de la subfamilia Physodoceratinae, la simplificación observada en la morfología de la sutura puede tener un doble origen. En primer lugar, un incremento en el tamaño de los tubérculos periumbilicales puede determinar una pérdida de profundidad de los elementos de la sutura. siempre acompañada de una disminución en las indentaciones (frilling de sillas y lóbulos. En otros casos el acortamiento en profundidad está determinado por una disminución de la tasa de expansión de la espira, sin que se observe un acortamiento aparente de las ramificaciones secundarias.

Short- and long-term results of chordal reconstruction using artificial suture material (polytetrafluoroethylene and polypropylene in the dog

Directory of Open Access Journals (Sweden)

Isamu Kanemoto

2017-04-01

Full Text Available No previous reports have compared the suitability of expanded polytetrafluoroethylene (ePTFE and polypropylene as artificial suture materials for chordal reconstruction in mitral valve plasty (MVP in the dog. Twelve normal dogs were subjected to MVP using surfaceinduced deep hypothermia. In the short-term group (1.5-4 months after surgery, all ePTFE sutures were covered by a tissue sheath including the paired suture arms, which gave the appearance of native chordae from 2 months after surgery. In contrast, all polypropylene sutures were not covered by tissue, and appeared the same as the paired polypropylene suture arms at the operation. In the long-term group (12 months after surgery, all ePTFE sutures were covered by a tissue sheath, which appeared the same as that in the short-term group, and had flexibility without increased thickness with time. In contrast, although the polypropylene suture was covered completely by a tissue sheath in 1 dog, all the other polypropylene sutures were exposed except for both ends of the suture. ePTFE may be superior to polypropylene as an artificial suture material for chordal reconstruction in MVP.

Contact area and pressure in suture bridge rotator cuff repair using knotless lateral anchors.

Science.gov (United States)

Tompkins, Marc; Monchik, Keith O; Plante, Matthew J; Fleming, Braden C; Fadale, Paul D

2011-10-01

To evaluate whether the use of knotless lateral anchors in a suture bridge construct produces better contact area and pressure parameters than a suture bridge construct with standard lateral anchors that require knots or a double-row repair. The hypothesis was that knotless lateral anchors would produce better contact area and pressure parameters than the other two constructs. A total of fifteen matched pairs of cadaveric shoulders were divided into three groups. In Group 1, a suture bridge using knotless anchors for the lateral row was performed on five shoulders. A suture bridge using standard lateral row anchors that require knots was performed on the contralateral shoulders. In Group 2, suture bridge with knotless lateral row anchors was compared with double-row repair. In Group 3, suture bridge using standard lateral row anchors was compared with double-row repair. The contact conditions of the rotator cuff footprint were measured using pressure-sensitive film. There were no statistically significant differences between any of the techniques regarding contact area F(2, 15.7) = 3.09, P = 0.07 or mean contact pressure F(2, 15.1) = 2.35, P = 0.12. A post hoc power analysis suggests differences between techniques are likely less than 91-113 mm(2) for area and 0.071-0.089 N for pressure. The use of knotless anchors in the lateral row of a suture bridge repair did not increase the footprint contact area or contact pressure when compared to a suture bridge repair requiring knots laterally or to a double-row repair.

Atomic-scale structure of single-layer MoS2 nanoclusters

DEFF Research Database (Denmark)

Helveg, S.; Lauritsen, J. V.; Lægsgaard, E.

2000-01-01

We have studied using scanning tunneling microscopy (STM) the atomic-scale realm of molybdenum disulfide (MoS2) nanoclusters, which are of interest as a model system in hydrodesulfurization catalysis. The STM gives the first real space images of the shape and edge structure of single-layer MoS2...

Towards single step production of multi-layer inorganic hollow fibers

NARCIS (Netherlands)

de Jong, J.; Benes, Nieck Edwin; Koops, G.H.; Wessling, Matthias

2004-01-01

In this work we propose a generic synthesis route for the single step production of multi-layer inorganic hollow fibers, based on polymer wet spinning combined with a heat treatment. With this new method, membranes with a high surface area per unit volume ratio can be produced, while production time

Single-layer graphene on silicon nitride micromembrane resonators

Energy Technology Data Exchange (ETDEWEB)

Schmid, Silvan; Guillermo Villanueva, Luis; Amato, Bartolo; Boisen, Anja [Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345 East, 2800 Kongens Lyngby (Denmark); Bagci, Tolga; Zeuthen, Emil; Sørensen, Anders S.; Usami, Koji; Polzik, Eugene S. [QUANTOP, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen (Denmark); Taylor, Jacob M. [Joint Quantum Institute/NIST, College Park, Maryland 20899 (United States); Herring, Patrick K.; Cassidy, Maja C. [School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts 02138 (United States); Marcus, Charles M. [Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen (Denmark); Cheol Shin, Yong; Kong, Jing [Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2014-02-07

Due to their low mass, high quality factor, and good optical properties, silicon nitride (SiN) micromembrane resonators are widely used in force and mass sensing applications, particularly in optomechanics. The metallization of such membranes would enable an electronic integration with the prospect for exciting new devices, such as optoelectromechanical transducers. Here, we add a single-layer graphene on SiN micromembranes and compare electromechanical coupling and mechanical properties to bare dielectric membranes and to membranes metallized with an aluminium layer. The electrostatic coupling of graphene covered membranes is found to be equal to a perfectly conductive membrane, without significantly adding mass, decreasing the superior mechanical quality factor or affecting the optical properties of pure SiN micromembranes. The concept of graphene-SiN resonators allows a broad range of new experiments both in applied physics and fundamental basic research, e.g., for the mechanical, electrical, or optical characterization of graphene.

Cranial Suture Closure in Domestic Dog Breeds and Its Relationships to Skull Morphology.

Science.gov (United States)

Geiger, Madeleine; Haussman, Sinah

2016-04-01

Bulldog-type brachycephalic domestic dog breeds are characterized by a relatively short and broad skull with a dorsally rotated rostrum (airorhynchy). Not much is known about the association between a bulldog-type skull conformation and peculiar patterns of suture and synchondrosis closure in domestic dogs. In this study, we aim to explore breed-specific patterns of cranial suture and synchondrosis closure in relation to the prebasial angle (proxy for airorhynchy and thus bulldog-type skull conformation) in domestic dogs. For this purpose, we coded closure of 18 sutures and synchondroses in 26 wolves, that is, the wild ancestor of all domestic dogs, and 134 domestic dogs comprising 11 breeds. Comparisons of the relative amount of closing and closed sutures and synchondroses (closure scores) in adult individuals showed that bulldog-type breeds have significantly higher closure scores than non-bulldog-type breeds and that domestic dogs have significantly higher closure scores than the wolf. We further found that the prebasial angle is significantly positively correlated with the amount of closure of the basispheno-presphenoid synchondrosis and sutures of the nose (premaxillo-nasal and maxillo-nasal) and the palate (premaxillo-maxillary and interpalatine). Our results show that there is a correlation between patterns of suture and synchondrosis closure and skull shape in domestic dogs, although the causal relationships remain elusive. © 2016 Wiley Periodicals, Inc.

Study of energy transfer in single and multi-emissive layer using Gaussian peak fitting

International Nuclear Information System (INIS)

Yoon, Ju-An; Kim, You-Hyun; Kim, Nam Ho; Moon, Chang-Bum; He, Gufeng; Kim, Woo Young

2014-01-01

White organic light-emitting diodes(WOLEDs) were fabricated with the device structure of ITO(1800 Å)/NPB(700 Å)/emissive layer(300 Å)/Bphen(300 Å)/Liq(20 Å)/Al(1200 Å) using the two complementary colors method. Then, we investigated their electrical and optical characteristics to determine luminous efficiency, luminance and color coordinates of single, double, triple and quadruple emissive layered-WOLED. Thickness of emissive layer was fixed at 30 Å, and DPASN and BAlq were used for blue emissive host material and DCJTB was added as red dopant in the emissive layer. Then, we investigated the performance of OLEDs via its charge blocking structure and its different emissive region with emissive layers. Luminous efficiency of 5.30 cd/A at 50 mA/cm 2 of current density is obtained in WOLED device with double emissive layer of DPASN:DCJTB-0.1% (150 Å)/BAlq:DCJTB-0.1% (150 Å) and these are 80% higher than WOLED device with single emissive layer of DPASN:DCJTB-0.1% (300 Å). - Highlights: • White OLEDs with multiple-emissive layer were fabricated using p- and n-type emissive materials. • We fabricated WOLEDs only using a small quantity of fluorescent red dopant materials. • The spectroscopic analysis using multi-peak fits with a Gaussian function. • The explain electroluminescence spectra of white OLEDs with the multiple-emissive layer. • We examine changes in the number of emissive layer about white OLEDs performance

Using Capacitance Sensors for the Continuous Measurement of the Water Content in the Litter Layer of Forest Soil

Directory of Open Access Journals (Sweden)

Mioko Ataka

2014-01-01

Full Text Available Little is known about the wetting and drying processes of the litter layer (L layer, likely because of technical difficulties inherent in nondestructive water content (WC monitoring. We developed a method for continuously measuring the WC of leaf litter (the “LWC method” in situ using capacitance sensors. To test variants of this approach, five (for the LWC_5 or ten (for the LWC_10 method Quercus serrata leaves were attached around capacitance sensors. The output voltage used for each LWC method was linearly correlated with the gravimetric WC (LWC_5: R2=0.940; LWC_10: R2=0.942, producing different slopes for each calibration line. For in situ continuous measurements of WC in the L layer, two sensors were used, one placed on top of the L layer and the other at the boundary between the L and mineral layers. The average continuous WC of the L layer was then calculated from the output voltage of the two sensors and the calibration function, and this value was linearly correlated with the gravimetric WC (R2=0.697. However, because the L layer characteristics (e.g., thickness, water-holding capacity, and species composition may differ among study sites, appropriate approaches for measuring this layer’s moisture properties may be needed.

Elasticity and breaking strength of synthetic suture materials incubated in various equine physiological and pathological solutions.

Science.gov (United States)

Kearney, C M; Buckley, C T; Jenner, F; Moissonnier, P; Brama, P A J

2014-07-01

Selection of suture material in equine surgery is often based on costs or subjective factors, such as the surgeon's personal experience, rather than objective facts. The amount of objective data available on durability of suture materials with regard to specific equine physiological conditions is limited. To evaluate the effect of various equine physiological and pathological fluids on the rate of degradation of a number of commonly used suture materials. In vitro material testing. Suture materials were exposed in vitro to physiological fluid, followed by biomechanical analysis. Three absorbable suture materials, glycolide/lactide copolymer, polyglactin 910 and polydioxanone were incubated at 37°C for 7, 14 or 28 days in phosphate-buffered saline, equine serum, equine urine and equine peritoneal fluid from an animal with peritonitis. Five strands of each suture material type were tested to failure in a materials testing machine for each time point and each incubation medium. Yield strength, strain and Young's modulus were calculated, analysed and reported. For all suture types, the incubation time had a significant effect on yield strength, percentage elongation and Young's modulus in all culture media (Ptype was also shown significantly to influence changes in each of yield strength, percentage elongation and Young's modulus in all culture media (Ptype of fluid have significant effects on the biomechanical properties of various suture materials. These findings are important for evidence-based selection of suture material in clinical cases. © 2013 EVJ Ltd.

Long-term efficacy of anchored barbed sutures in the face and neck.

Science.gov (United States)

Kaminer, Michael S; Bogart, Megan; Choi, Christine; Wee, Sue Ann

2008-08-01

The thread lift is a minimally invasive procedure that uses barbed sutures, inserted subcutaneously, to produce lifting of ptotic tissue of the face and neck. There are currently very limited data on longevity and patient satisfaction following barbed suture lifting procedures. The purpose of this study was to assess long-term efficacy following the use of barbed sutures. A satisfaction survey was mailed to 20 patients who were a minimum of 6 months (range, 6 to 16 months) postprocedure. Physician assessment of pre- and postprocedure photographs was also performed. At an average of 11.5 months postprocedure, patients felt that the barbed suture lift met their expectations, rating their satisfaction a 6.9 on a scale of 1 to 10. Independent physicians rated the overall improvement an average of 4.6 of 10. Higher scores were noted in Zone 1 (tear trough/malar fat pad and nasolabial folds) compared to Zone 2 (marionette lines, jowls, and jawline definition) and Zone 3 (platysmal bands and neck contour). The barbed suture lift procedure provides moderate long-term and sustained improvement for facial laxity, with most improvement seen in the tear trough/malar fat pads and nasolabial folds. In this study, clinical efficacy was seen up to 16 months postprocedure.

Emergence of charge density waves and a pseudogap in single-layer TiTe2.

Science.gov (United States)

Chen, P; Pai, Woei Wu; Chan, Y-H; Takayama, A; Xu, C-Z; Karn, A; Hasegawa, S; Chou, M Y; Mo, S-K; Fedorov, A-V; Chiang, T-C

2017-09-11

Two-dimensional materials constitute a promising platform for developing nanoscale devices and systems. Their physical properties can be very different from those of the corresponding three-dimensional materials because of extreme quantum confinement and dimensional reduction. Here we report a study of TiTe 2 from the single-layer to the bulk limit. Using angle-resolved photoemission spectroscopy and scanning tunneling microscopy and spectroscopy, we observed the emergence of a (2 × 2) charge density wave order in single-layer TiTe 2 with a transition temperature of 92 ± 3 K. Also observed was a pseudogap of about 28 meV at the Fermi level at 4.2 K. Surprisingly, no charge density wave transitions were observed in two-layer and multi-layer TiTe 2 , despite the quasi-two-dimensional nature of the material in the bulk. The unique charge density wave phenomenon in the single layer raises intriguing questions that challenge the prevailing thinking about the mechanisms of charge density wave formation.Due to reduced dimensionality, the properties of 2D materials are often different from their 3D counterparts. Here, the authors identify the emergence of a unique charge density wave (CDW) order in monolayer TiTe 2 that challenges the current understanding of CDW formation.

Flexor tendon repair: a comparative study between a knotless barbed suture repair and a traditional four-strand monofilament suture repair.

LENUS (Irish Health Repository)

Joyce, C W

2014-01-01

We compared the tensile strength of a novel knotless barbed suture method with a traditional four-strand Adelaide technique for flexor tendon repairs. Forty fresh porcine flexor tendons were transected and randomly assigned to one of the repair groups before repair. Biomechanical testing demonstrated that the tensile strengths between both tendon groups were very similar. However, less force was required to create a 2 mm gap in the four-strand repair method compared with the knotless barbed technique. There was a significant reduction in the cross-sectional area in the barbed suture group after repair compared with the Adelaide group. This would create better gliding within the pulley system in vivo and could decrease gapping and tendon rupture.

Thread-Lift Sutures: Still in the Lift? A Systematic Review of the Literature.

Science.gov (United States)

Gülbitti, Haydar Aslan; Colebunders, Britt; Pirayesh, Ali; Bertossi, Dario; van der Lei, Berend

2018-03-01

In 2006, Villa et al. published a review article concerning the use of thread-lift sutures and concluded that the technique was still in its infancy but had great potential to become a useful and effective procedure for nonsurgical lifting of sagged facial tissues. As 11 years have passed, the authors now performed again a systematic review to determine the real scientific current state of the art on the use of thread-lift sutures. A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the PubMed database and using the Medical Subject Headings search term "Rhytidoplasty." "Rhytidoplasty" and the following entry terms were included by this Medical Subject Headings term: "facelift," "facelifts," "face Lift," "Face Lifts," "Lift," "Face," "Lifts," "Platysmotomy," "Platysmotomies," "Rhytidectomy," "Rhytidectomies," "Platysmaplasty," "and "Platysmaplasties." The Medical Subject Headings term "Rhytidoplasty" was combined with the following search terms: "Barbed suture," "Thread lift," "APTOS," "Suture suspension," "Percutaneous," and "Silhouette suture." RefWorks was used to filter duplicates. Three of the authors (H.A.G., B.C., and B.L.) performed the search independently. The initial search with all search terms resulted in 188 articles. After filtering the duplicates and the articles about open procedures, a total of 41 articles remained. Of these, the review articles, case reports, and letters to the editor were subsequently excluded, as were reports dealing with nonbarbed sutures, such as Vicryl and Prolene with Gore-Tex. This resulted in a total of 12 articles, seven additional articles since the five articles reviewed by Villa et al. The authors' review demonstrated that, within the past decade, little or no substantial evidence has been added to the peer-reviewed literature to support or sustain the promising statement about thread-lift sutures as made by Villa et al. in 2006 in terms of

Radiological assessment of skull base changes in children with syndromic craniosynostosis: role of ''minor'' sutures

International Nuclear Information System (INIS)

Calandrelli, Rosalinda; D'Apolito, Gabriella; Gaudino, Simona; Stefanetti, Mariangela; Colosimo, Cesare; Massimi, Luca; Di Rocco, Concezio

2014-01-01

This study aims to identify the premature synostosis of ''major'' and ''minor'' sutures of the four ''sutural arches'' of the skull and to perform a morphometric analysis in children with syndromic craniosynostosis in order to evaluate changes in the skull base linked with premature suture synostosis. We reviewed multiplanar high-resolution CT images, implemented with 3D reconstructions, from 18 patients with complex syndromic craniosynostosis and compared them with 18 age-matched healthy subjects. We assessed the calvarial sutures and their extension to the skull base, and then we correlated specific types of synostosis with the size, shape and symmetry of the cranial fossae. We found a marked asymmetry of the skull base growth in all patients. The synostotic involvement around the coronal ring caused a reduction in the growth of the anterior and middle fossae. The size of the posterior cranial fossa was related not only to ''major'' but also to ''minor'' suture synostosis of the lambdoid and parieto-squamosal arches. Changes in the skull base and craniofacial axis symmetry are due to structural and functional relationships between ''major'' and ''minor'' skull sutures, suggesting a structural and functional relationship between the neurocranium and basicranium. The early recognition of prematurely closed skull base sutures may help clinicians and neurosurgeons to establish correct therapeutic approaches. (orig.)

Generation of organized germ layers from a single mouse embryonic stem cell.

Science.gov (United States)

Poh, Yeh-Chuin; Chen, Junwei; Hong, Ying; Yi, Haiying; Zhang, Shuang; Chen, Junjian; Wu, Douglas C; Wang, Lili; Jia, Qiong; Singh, Rishi; Yao, Wenting; Tan, Youhua; Tajik, Arash; Tanaka, Tetsuya S; Wang, Ning

2014-05-30

Mammalian inner cell mass cells undergo lineage-specific differentiation into germ layers of endoderm, mesoderm and ectoderm during gastrulation. It has been a long-standing challenge in developmental biology to replicate these organized germ layer patterns in culture. Here we present a method of generating organized germ layers from a single mouse embryonic stem cell cultured in a soft fibrin matrix. Spatial organization of germ layers is regulated by cortical tension of the colony, matrix dimensionality and softness, and cell-cell adhesion. Remarkably, anchorage of the embryoid colony from the 3D matrix to collagen-1-coated 2D substrates of ~1 kPa results in self-organization of all three germ layers: ectoderm on the outside layer, mesoderm in the middle and endoderm at the centre of the colony, reminiscent of generalized gastrulating chordate embryos. These results suggest that mechanical forces via cell-matrix and cell-cell interactions are crucial in spatial organization of germ layers during mammalian gastrulation. This new in vitro method could be used to gain insights on the mechanisms responsible for the regulation of germ layer formation.

Suture Granuloma Showing False-Positive Findings on FDG-PET

Directory of Open Access Journals (Sweden)

Kohei Takahara

2013-01-01

Full Text Available We report a case of a 33-year-old male with a mixed germ-cell testicular tumor. Postoperative follow-up FDG-PET revealed concentration of FDG in the left inguinal area which is not tumor metastasis or local recurrence but suture reactivity granuloma. In this paper, we reviewed suture granulomas associated with false-positive findings on FDG-PET after surgery. If FDG-PET will be used more frequently in the future, it will be necessary to refrain from using silk thread in order to prevent any unnecessary surgery.

A reusable suture anchor for arthroscopy psychomotor skills training.

Science.gov (United States)

Tillett, Edward D; Rogers, Rainie; Nyland, John

2003-03-01

For residents to adequately develop the early arthroscopy psychomotor skills required to better learn how to manage the improvisational situations they will encounter during actual patient cases, they need to experience sufficient practice repetitions within a contextually relevant environment. Unfortunately, the cost of suture anchors can be a practice repetition-limiting factor in learning arthroscopic knot-tying techniques. We describe a technique for creating inexpensive reusable suture anchors and provide an example of their application to repair the anterior glenoid labrum during an arthroscopy psychomotor skills laboratory training session.

Exposure buildup factors for a cobalt-60 point isotropic source for single and two layer slabs

International Nuclear Information System (INIS)

Chakarova, R.

1992-01-01

Exposure buildup factors for point isotropic cobalt-60 sources are calculated by the Monte Carlo method with statistical errors ranging from 1.5 to 7% for 1-5 mean free paths (mfp) thick water and iron single slabs and for 1 and 2 mfp iron layers followed by water layers 1-5 mfp thick. The computations take into account Compton scattering. The Monte Carlo data for single slab geometries are approximated by Geometric Progression formula. Kalos's formula using the calculated single slab buildup factors may be applied to reproduce the data for two-layered slabs. The presented results and discussion may help when choosing the manner in which the radiation field gamma irradiation units will be described. (author)

Oesophageal flap valvuloplasty and wrapping suturing prevent gastrooesophageal reflux disease in dogs after oesophageal anastomosis

Science.gov (United States)

Dai, Ji-Gang; Liu, Quan-Xing; Den, Xu-Feng; Min, Jia-Xin

2014-01-01

AIM: To examine the efficiency of oesophageal flap valvuloplasty and wrapping suturing technique in decreasing the rate of postoperative gastrooesophageal reflux disease in a dog model. METHODS: We operated on 10 dogs in this study. First, we resected a 5-cm portion of the distal oesophagus and then restored the continuity of the oesophageal and gastric walls by end-to-end anastomosis. A group of five dogs was subjected to the oesophageal flap valvuloplasty and wrapping suturing technique, whereas another group (control) of five dogs was subjected to the stapling technique after oesophagectomy. The symptom of gastrooesophageal reflux was recorded by 24-h pH oesophageal monitoring. Endoscopy and barium swallow examination were performed on all dogs. Anastomotic leakage was observed by X-ray imaging, whereas benign anastomotic stricture and mucosal damage were observed by endoscopy. RESULTS: None of the 10 dogs experienced anastomotic leakage after oesophagectomy. Four dogs in the new technology group resumed regular feeding, whereas only two of the dogs in the control group tolerated solid food intake. pH monitoring demonstrated that 25% of the dogs in the experimental group exhibited reflux and that none had mucosal damage consistent with reflux. Conversely, both reflux and mucosal damage were observed in all dogs in the control group. CONCLUSION: The oesophageal flap valvuloplasty and wrapping suturing technique can improve the postoperative quality of life through the long-term elimination of reflux oesophagitis and decreased stricture formation after primary oesophageal anastomosis. PMID:25516655

The suture provides a niche for mesenchymal stem cells of craniofacial bones

Science.gov (United States)

Zhao, Hu; Feng, Jifan; Ho, Thach-Vu; Grimes, Weston; Urata, Mark; Chai, Yang

2015-01-01

Bone tissue undergoes constant turnover supported by stem cells. Recent studies showed that perivascular mesenchymal stem cells (MSCs) contribute to the turnover of long bones. Craniofacial bones are flat bones derived from a different embryonic origin than the long bones. The identity and regulating niche for craniofacial bone MSCs remain unknown. Here, we identify Gli1+ cells within the suture mesenchyme as the major MSC population for craniofacial bones. They are not associated with vasculature, give rise to all craniofacial bones in the adult and are activated during injury repair. Gli1+ cells are typical MSCs in vitro. Ablation of Gli1+ cells leads to craniosynostosis and arrest of skull growth, indicating these cells are an indispensible stem cell population. Twist1+/− mice with craniosynostosis show reduced Gli1+ MSCs in sutures, suggesting that craniosynostosis may result from diminished suture stem cells. Our study indicates that craniofacial sutures provide a unique niche for MSCs for craniofacial bone homeostasis and repair. PMID:25799059

Shape memory alloy fixator system for suturing tissue in minimal access surgery.

Science.gov (United States)

Xu, W; Frank, T G; Stockham, G; Cuschieri, A

1999-01-01

A new technique for suturing human tissue is described in which tissue closure is achieved by means of small fixators made from shape memory alloy. The aim of the development is to provide an alternative to thread suturing in minimal access surgery, which is quicker and requires less skill to achieve the required suturing quality. The design of the fixators is described in terms of the thermal shape recovery of shape memory alloy and a novel form of finite element analysis, which uses a nonlinear elastic element for the material property. Thermal analysis of the fixators and surrounding tissue is used to predict the temperature distribution during and after the application of electric current heating. This was checked in an in vitro experiment, which confirmed that deployment caused no detectable collateral damage to surrounding tissue. In vivo animal studies on the use of the shape memory alloy fixator for suturing tissue are ongoing to establish safety and healing effects.

Single layers and multilayers of GaN and AlN in square-octagon structure: Stability, electronic properties, and functionalization

Science.gov (United States)

Gürbüz, E.; Cahangirov, S.; Durgun, E.; Ciraci, S.

2017-11-01

Further to planar single-layer hexagonal structures, GaN and AlN can also form free-standing, single-layer structures constructed from squares and octagons. We performed an extensive analysis of dynamical and thermal stability of these structures in terms of ab initio finite-temperature molecular dynamics and phonon calculations together with the analysis of Raman and infrared active modes. These single-layer square-octagon structures of GaN and AlN display directional mechanical properties and have wide, indirect fundamental band gaps, which are smaller than their hexagonal counterparts. These density functional theory band gaps, however, increase and become wider upon correction. Under uniaxial and biaxial tensile strain, the fundamental band gaps decrease and can be closed. The electronic and magnetic properties of these single-layer structures can be modified by adsorption of various adatoms, or by creating neutral cation-anion vacancies. The single-layer structures attain magnetic moment by selected adatoms and neutral vacancies. In particular, localized gap states are strongly dependent on the type of vacancy. The energetics, binding, and resulting electronic structure of bilayer, trilayer, and three-dimensional (3D) layered structures constructed by stacking the single layers are affected by vertical chemical bonds between adjacent layers. In addition to van der Waals interaction, these weak vertical bonds induce buckling in planar geometry and enhance their binding, leading to the formation of stable 3D layered structures. In this respect, these multilayers are intermediate between van der Waals solids and wurtzite crystals, offering a wide range of tunability.

Buried oxide layer in silicon

Science.gov (United States)

Sadana, Devendra Kumar; Holland, Orin Wayne

2001-01-01

A process for forming Silicon-On-Insulator is described incorporating the steps of ion implantation of oxygen into a silicon substrate at elevated temperature, ion implanting oxygen at a temperature below 200.degree. C. at a lower dose to form an amorphous silicon layer, and annealing steps to form a mixture of defective single crystal silicon and polycrystalline silicon or polycrystalline silicon alone and then silicon oxide from the amorphous silicon layer to form a continuous silicon oxide layer below the surface of the silicon substrate to provide an isolated superficial layer of silicon. The invention overcomes the problem of buried isolated islands of silicon oxide forming a discontinuous buried oxide layer.

Early secondary suture versus healing by second intention of incisional abscesses

DEFF Research Database (Denmark)

Hermann, G G; Bagi, P; Christoffersen, I

1988-01-01

A controlled trial was set up to compare the treatment of wound abscesses, occurring after laparotomy, with either early secondary suture combined with cefuroxime and metronidazole given intravenously or by healing by second intention. The secondary suture was performed two days after wound...... drainage and resulted in a significant reduction (p less than 0.01) in healing time without complications. No reinfections occurred....

Compositional control of continuously graded anode functional layer

Science.gov (United States)

McCoppin, J.; Barney, I.; Mukhopadhyay, S.; Miller, R.; Reitz, T.; Young, D.

2012-10-01

In this work, solid oxide fuel cells (SOFC's) are fabricated with linear-compositionally graded anode functional layers (CGAFL) using a computer-controlled compound aerosol deposition (CCAD) system. Cells with different CGAFL thicknesses (30 um and 50 um) are prepared with a continuous compositionally graded interface deposited between the electrolyte and anode support current collecting regions. The compositional profile was characterized using energy dispersive X-ray spectroscopic mapping. An analytical model of the compound aerosol deposition was developed. The model predicted compositional profiles for both samples that closely matched the measured profiles, suggesting that aerosol-based deposition methods are capable of creating functional gradation on length scales suitable for solid oxide fuel cell structures. The electrochemical performances of the two cells are analyzed using electrochemical impedance spectroscopy (EIS).

Early functional outcome of a modified Brostrom-Gould surgery using bioabsorbable suture anchor for chronic lateral ankle instability.

Science.gov (United States)

Shahrulazua, A; Ariff Sukimin, M S; Tengku Muzaffar, T M; Yusof, M I

2010-03-01

The purpose of this study was to evaluate the early functional outcome following the use of a bioabsorbable suture anchor to simplify the repair of injured lateral ankle structures as a variation of an established technique known as the Brostrom-Gould procedure. This was a prospective study of 30 ankles with chronic lateral instability that underwent a modified Brostrom-Gould surgery using a bioabsorbable suture anchor, performed by a single surgeon. A total of 29 patients, aged 15 to 52 (mean is 33) years, were enrolled in the study. The follow-up period ranged from three to six (mean is four) months. The function of the patients' ankles was scored using the Kaikkonen Functional Scale, both preoperatively and postoperatively. Preoperatively, all ankles had poor scores (less than 50). Postoperatively, 28 ankles showed excellent scores and two ankles showed good scores, while none obtained a fair or poor score. The difference in the overall means between the postoperative and preoperative scores was statistically significant (p-value is 0.001). Post surgery, 24 ankles had no symptoms, while six had only mild ankle tightness with extreme inversion movement at the last review. All patients were able to walk normally, and 29 ankles regained their normal running capability. There was marked improvement in the ability to descend stairs, to rise on heels and toes, to perform a single-limb stance, and in range of motions of the ankle dorsiflexion as well as in ankle laxity. The modified Brostrom-Gould procedure using a bioabsorbable suture anchor allowed for early ankle rehabilitation and offered a reproducible and excellent early functional outcome with minimal complications.

A Randomized Study Comparing Outcomes of Stapled and Hand-Sutured Anastomoses in Patients Undergoing Open Gastrointestinal Surgery

OpenAIRE

Chandramohan, S. M.; Gajbhiye, Raj Narenda; Agwarwal, Anil; Creedon, Erin; Schwiers, Michael L.; Waggoner, Jason R.; Tatla, Daljit

2012-01-01

Although stapling is an alternative to hand-suturing in gastrointestinal surgery, recent trials specifically designed to evaluate differences between the two in surgery time, anastomosis time, and return to bowel activity are lacking. This trial compared the outcomes of the two in subjects undergoing open gastrointestinal surgery. Adult subjects undergoing emergency or elective surgery requiring a single gastric, small, or large bowel anastomosis were enrolled into this open-label, prospectiv...

The efficacy of laparoscopic intracorporeal linear suture technique as a strategy for reducing recurrences in pediatric inguinal hernia.

Science.gov (United States)

Lee, S R; Choi, S B

2017-06-01

Pediatric laparoscopic herniorrhaphy has rare complications, but recurrence might occur. The purpose of this manuscript is to evaluate the efficacy of linear suture technique of laparoscopic pediatric herniorrhaphy in reducing recurrences. Laparoscopic surgery was performed on 2223 pediatric patients (under 10 years old) from September 2012 to December 2014 in Damsoyu Hospital, Seoul, Republic of Korea. The causes of recurrence were investigated case by case. The patients were categorized into two groups according to the suture method used in closing the hernia orifice: Group 1 (purse-string suture, 1009 patients) and Group 2 (linear suture, 1214 patients). There were 1413 (63.6%) male and 810 (36.4%) female patients. Mean age was 30.5 ± 29.2 months. A significantly higher proportion of male patients, contralateral patent processus vaginalis, and less proportion of recurrence were observed in Group 2. There were ten cases of recurrence in Group 1 because the internal ring suture could not endure the tension. One recurrence occurred in Group 2. The suture technique and age were found to be a significant risk factor for recurrence. Linear suture technique had a lower recurrence rate (odds ratio = 0.07, with 95% confidence interval 0.01-0.53, and p = 0.004). Purse-string suture technique causes significantly higher occurrence of hernia recurrences than linear suture technique. Linear suture technique can reduce recurrence by increasing the endurance to tension around the internal ring by distributing pressure to a wider area along the linear suture line. Linear suture technique can effectively reduce recurrence in pediatric inguinal herniorrhaphy.

Biomechanical analysis of suture locations of the distal plantar fascia in partial foot.

Science.gov (United States)

Guo, Jun-Chao; Wang, Li-Zhen; Mo, Zhong-Jun; Chen, Wei; Fan, Yu-Bo

2015-12-01

The aim of this study was to evaluate the rationality of the suture locations of distal plantar fascia (DPF) after foot amputation to avoid the risk factors of re-amputation or plantar fasciitis. The tensile strain of plantar fascia (PF) in the different regions was measured by uni-axial tensile experiment. A three-dimensional (3D) finite element model was also developed to simulate tensile behaviour of PF in weight bearing conditions. The model includes 12 bones, ligaments, PF, cartilage and soft tissues. Four suture location models for the DPF were considered: the fourth and fifth DPF were sutured on the third metatarsal, the cuboid, and both the third metatarsal and the cuboid, and one un-sutured model. The peak tensile strain of the first, second and third PF was 0.134, 0.128 and 0.138 based on the mechanical test, respectively. The fourth and fifth DPF sutured at the cuboid and the third metatarsal could offer more favourable outcomes. The peak strain of 4.859 × 10(-2), 2.347 × 10(-2) and 1.364 × 10(-2) in the first, second and third PF showed the least outcomes in stance phase. Also, peak strain and stress of the residual PF reduced to 4.859 × 10(-2) and 1.834 MPa, respectively. The stress region was redistributed on the mid-shaft of the first and third PF and the peak stress of medial cuneiform bone evidently decreased. The fourth and fifth DPF suture at the third metatarsal and cuboid was appropriate for the partial foot. The findings are expected to suggest optimal surgical plan of the DPF suture and guide further therapeutic planning of partial foot patients.

Bio-inspired ``jigsaw''-like interlocking sutures: Modeling, optimization, 3D printing and testing

Science.gov (United States)

Malik, I. A.; Mirkhalaf, M.; Barthelat, F.

2017-05-01

Structural biological materials such as bone, teeth or mollusk shells draw their remarkable performance from a sophisticated interplay of architectures and weak interfaces. Pushed to the extreme, this concept leads to sutured materials, which contain thin lines with complex geometries. Sutured materials are prominent in nature, and have recently served as bioinspiration for toughened ceramics and glasses. Sutures can generate large deformations, toughness and damping in otherwise all brittle systems and materials. In this study we examine the design and optimization of sutures with a jigsaw puzzle-like geometry, focusing on the non-linear traction behavior generated by the frictional pullout of the jigsaw tabs. We present analytical models which accurately predict the entire pullout response. Pullout strength and energy absorption increase with higher interlocking angles and for higher coefficients of friction, but the associated high stresses in the solid may fracture the tabs. Systematic optimization reveals a counter-intuitive result: the best pullout performance is achieved with interfaces with low coefficient of friction and high interlocking angle. We finally use 3D printing and mechanical testing to verify the accuracy of the models and of the optimization. The models and guidelines we present here can be extended to other types of geometries and sutured materials subjected to other loading/boundary conditions. The nonlinear responses of sutures are particularly attractive to augment the properties and functionalities of inherently brittle materials such as ceramics and glasses.

Edge structures and properties of triangular antidots in single-layer MoS2

International Nuclear Information System (INIS)

Gan, Li-Yong; Cheng, Yingchun; Huang, Wei; Schwingenschlögl, Udo; Yao, Yingbang; Zhao, Yong; Zhang, Xi-xiang

2016-01-01

Density functional theory and experiments are employed to shed light on the edge structures of antidots in O etched single-layer MoS 2 . The equilibrium morphology is found to be the zigzag Mo edge with each Mo atom bonded to two O atoms, in a wide range of O chemical potentials. Scanning electron microscopy shows that the orientation of the created triangular antidots is opposite to the triangular shape of the single-layer MoS 2 samples, in agreement with the theoretical predictions. Furthermore, edges induced by O etching turn out to be p-doped, suggesting an effective strategy to realize p-type MoS 2 devices.

Interfascicular suture with nerve autografts for median, ulnar and radial nerve lesions.

Science.gov (United States)

Pluchino, F; Luccarelli, G

1981-05-01

Interfascicular nerve suture with autografts is the operation of choice for repairing peripheral nerve injuries because it ensures more precise alignment of the fasciculi and so better chances of reinnervation of the sectioned nerve. The procedure as described by Millesi et al has been used at the Istituto Neurologico di Milano in 30 patients with traumatic lesions of the median, ulnar and radial nerves. All have been followed up for 2 to 7 years since operation. The results obtained are compared with those of other series obtained with interfascicular suture and with epineural suture. Microsurgery is essential. The best time to operate is discussed.

Adjustment of gamma radiation doses for sterilization of Egyptian surgical sutures

International Nuclear Information System (INIS)

Tawfik, Z.S.; Helmy, M.M.; Roushdy, H.M.

1984-01-01

The adjustment of gamma radiation doses for sterilization of catguts under local manufacturing conditions has been performed. Average total initial counts for aerobic and anaerobic bacteria per item were relatively low, in the range of 1000 counts for aerobic and 10 counts for anaerobic bacteria. The microfiora (aerobic bacteria) of the studied sutures were isolated and identified to be: Bacillus sp.; Micrococcus varians, Micrococcus roseus, and Staphylococcus. Each purified and identified isolate was exposed to gamma radiation both in liquid media (broth) and in the preservative in which the sutures were supplied by the company. The LD values of the most resistant microorganisms in both case of liquid media and preservative, were obtained to be around 5 KGy. Deliberately contaminated sterile sutures with each isolate and with mixture of isolates were studied. The sterilizing dose was obtained to be 20KGy for most heavily contaminated items (10 10 counts) irradiated both in saline and in preservative. This sterilizing dose was found to be dependent of the initial viable counts. This value was considered to be a safe value for radiosterilization of the studied sutures preserved in isopropyl alcohol, glycerin, and water (90:3.5:16)

Single-layer group IV-V and group V-IV-III-VI semiconductors: Structural stability, electronic structures, optical properties, and photocatalysis

Science.gov (United States)

Lin, Jia-He; Zhang, Hong; Cheng, Xin-Lu; Miyamoto, Yoshiyuki

2017-07-01

Recently, single-layer group III monochalcogenides have attracted both theoretical and experimental interest at their potential applications in photonic devices, electronic devices, and solar energy conversion. Excited by this, we theoretically design two kinds of highly stable single-layer group IV-V (IV =Si ,Ge , and Sn; V =N and P) and group V-IV-III-VI (IV =Si ,Ge , and Sn; V =N and P; III =Al ,Ga , and In; VI =O and S) compounds with the same structures with single-layer group III monochalcogenides via first-principles simulations. By using accurate hybrid functional and quasiparticle methods, we show the single-layer group IV-V and group V-IV-III-VI are indirect bandgap semiconductors with their bandgaps and band edge positions conforming to the criteria of photocatalysts for water splitting. By applying a biaxial strain on single-layer group IV-V, single-layer group IV nitrides show a potential on mechanical sensors due to their bandgaps showing an almost linear response for strain. Furthermore, our calculations show that both single-layer group IV-V and group V-IV-III-VI have absorption from the visible light region to far-ultraviolet region, especially for single-layer SiN-AlO and SnN-InO, which have strong absorption in the visible light region, resulting in excellent potential for solar energy conversion and visible light photocatalytic water splitting. Our research provides valuable insight for finding more potential functional two-dimensional semiconductors applied in optoelectronics, solar energy conversion, and photocatalytic water splitting.

Metal-Insulator-Metal Single Electron Transistors with Tunnel Barriers Prepared by Atomic Layer Deposition

Directory of Open Access Journals (Sweden)

Golnaz Karbasian

2017-03-01

Full Text Available Single electron transistors are nanoscale electron devices that require thin, high-quality tunnel barriers to operate and have potential applications in sensing, metrology and beyond-CMOS computing schemes. Given that atomic layer deposition is used to form CMOS gate stacks with low trap densities and excellent thickness control, it is well-suited as a technique to form a variety of tunnel barriers. This work is a review of our recent research on atomic layer deposition and post-fabrication treatments to fabricate metallic single electron transistors with a variety of metals and dielectrics.

Efficient and bright organic light-emitting diodes on single-layer graphene electrodes

Science.gov (United States)

Li, Ning; Oida, Satoshi; Tulevski, George S.; Han, Shu-Jen; Hannon, James B.; Sadana, Devendra K.; Chen, Tze-Chiang

2013-08-01

Organic light-emitting diodes are emerging as leading technologies for both high quality display and lighting. However, the transparent conductive electrode used in the current organic light-emitting diode technologies increases the overall cost and has limited bendability for future flexible applications. Here we use single-layer graphene as an alternative flexible transparent conductor, yielding white organic light-emitting diodes with brightness and efficiency sufficient for general lighting. The performance improvement is attributed to the device structure, which allows direct hole injection from the single-layer graphene anode into the light-emitting layers, reducing carrier trapping induced efficiency roll-off. By employing a light out-coupling structure, phosphorescent green organic light-emitting diodes exhibit external quantum efficiency >60%, while phosphorescent white organic light-emitting diodes exhibit external quantum efficiency >45% at 10,000 cd m-2 with colour rendering index of 85. The power efficiency of white organic light-emitting diodes reaches 80 lm W-1 at 3,000 cd m-2, comparable to the most efficient lighting technologies.

Single-hidden-layer feed-forward quantum neural network based on Grover learning.

Science.gov (United States)

Liu, Cheng-Yi; Chen, Chein; Chang, Ching-Ter; Shih, Lun-Min

2013-09-01

In this paper, a novel single-hidden-layer feed-forward quantum neural network model is proposed based on some concepts and principles in the quantum theory. By combining the quantum mechanism with the feed-forward neural network, we defined quantum hidden neurons and connected quantum weights, and used them as the fundamental information processing unit in a single-hidden-layer feed-forward neural network. The quantum neurons make a wide range of nonlinear functions serve as the activation functions in the hidden layer of the network, and the Grover searching algorithm outstands the optimal parameter setting iteratively and thus makes very efficient neural network learning possible. The quantum neuron and weights, along with a Grover searching algorithm based learning, result in a novel and efficient neural network characteristic of reduced network, high efficient training and prospect application in future. Some simulations are taken to investigate the performance of the proposed quantum network and the result show that it can achieve accurate learning. Copyright © 2013 Elsevier Ltd. All rights reserved.

Magnetic properties of serpentinized peridotites from the Zedong ophiolite, Yarlung-Zangbo suture zone, SE Tibet

Science.gov (United States)

Li, Z.; Zheng, J.; Moskowitz, B. M.; Xiong, Q.; Liu, Q.

2017-12-01

Serpentinized mantle peridotites are widely supposed to be significant sources of the magnetic, gravity and seismic anomalies in mid-oceanic ridges, forearcs and suture zones. However, the relationship between the magnetic properties of variably serpentinized peridotites and the serpentinization process is still under debate. Ophiolite outcrops commonly comprise peridotites in different stages of serpentinization and these ophiolitic peridotites are ideal to investigate the magnetic signatures of suture zones. The Zedong ophiolite locates in the eastern part of the Yarlung-Zangbo suture zone, SE Tibet (China), and the peridotite massif represents the remnants of the Neo-Tethyan lithospheric mantle. The harzburgite and lherzolite samples show densities between 3.316 and 2.593 g cm-3, and vary from the freshest to >90% serpentinized peridotites. The magnetic susceptibility curves from room temperature to 700ºC mainly show the Curie temperatures of 585ºC for pure magnetite. The low-temperature (20-300 K) demagnetization curves show the Verwey transitions at 115-125 K, suggesting that magnetite is also the dominant remanence-carrying phase. The hysteresis data of the peridotites fall in the region of pseudo-single-domain (PSD) and follow the theoretical trends for mixtures of single domain (SD) and multidomain (MD) magnetite. The first-order reversal curve (FORC) diagrams suggest that the magnetite is dominantly interacting SD + PSD particles for S 40% serpentinized samples. The susceptibility and saturation magnetization of the Zedong peridotites range from 0.9 to 30.8 × 10‒3 (SI) and 14.1 to 1318 × 10‒3 Am2 kg‒1, respectively, and both show consistent trends with increasing degrees of serpentinization. The S serpentinization of ophiolitic peridotites, whereas the S > 40% peridotites have higher susceptibilities of 0.02-0.03 (SI) and fall in the region of abyssal peridotites. Our results suggest that the Zedong ophiolitic peridotites probably experienced a

3D printed, bio-inspired prototypes and analytical models for structured suture interfaces with geometrically-tuned deformation and failure behavior

Science.gov (United States)

Lin, Erica; Li, Yaning; Ortiz, Christine; Boyce, Mary C.

2014-12-01

Geometrically structured interfaces in nature possess enhanced, and often surprising, mechanical properties, and provide inspiration for materials design. This paper investigates the mechanics of deformation and failure mechanisms of suture interface designs through analytical models and experiments on 3D printed polymer physical prototypes. Suture waveforms with generalized trapezoidal geometries (trapezoidal, rectangular, anti-trapezoidal, and triangular) are studied and characterized by several important geometric parameters: the presence or absence of a bonded tip region, the tip angle, and the geometry. It is shown that a wide range (in some cases as great as an order of magnitude) in stiffness, strength, and toughness is achievable dependent on tip bonding, tip angle, and geometry. Suture interfaces with a bonded tip region exhibit a higher initial stiffness due to the greater load bearing by the skeletal teeth, a double peak in the stress-strain curve corresponding to the failure of the bonded tip and the failure of the slanted interface region or tooth, respectively, and an additional failure and toughening mechanism due to the failure of the bonded tip. Anti-trapezoidal geometries promote the greatest amplification of properties for suture interfaces with a bonded tip due the large tip interface area. The tip angle and geometry govern the stress distributions in the teeth and the ratio of normal to shear stresses in the interfacial layers, which together determine the failure mechanism of the interface and/or the teeth. Rectangular suture interfaces fail by simple shearing of the interfaces. Trapezoidal and triangular suture interfaces fail by a combination of shear and tensile normal stresses in the interface, leading to plastic deformation, cavitation events, and subsequent stretching of interface ligaments with mostly elastic deformation in the teeth. Anti-trapezoidal suture interfaces with small tip angles have high stress concentrations in the teeth

Anatomic suture anchor versus the Broström technique for anterior talofibular ligament repair: a biomechanical comparison.

Science.gov (United States)

Waldrop, Norman E; Wijdicks, Coen A; Jansson, Kyle S; LaPrade, Robert F; Clanton, Thomas O

2012-11-01

Despite the popularity of the Broström procedure for secondary repair of chronic lateral ankle instability, there have been no biomechanical studies reporting on the strength of this secondary repair method, whether using suture fixation or suture anchors. The purpose of our study was to perform a biomechanical comparison of the ultimate load to failure and stiffness of the traditional Broström technique using only a suture repair compared with a suture anchor repair of the anterior talofibular ligament (ATFL) at time zero. We believed that fixation strength of the suture anchor repair would be closer to the strength of the native ligament and allow more aggressive rehabilitation. Controlled laboratory study. Twenty-four fresh-frozen cadaveric ankles were randomly divided into 4 groups of 6 specimens. One group was an intact control group, and the other groups consisted of the traditional Broström and 2 suture anchor modifications (suture anchors in talus or fibula) of the Broström procedure. The specimens were loaded to failure to determine the strength and stiffness of each construct. In load-to-failure testing, ultimate failure loads of the Broström (68.2 ± 27.8 N; P = .013), suture anchor fibula (79.2 ± 34.3 N; P = .037), and suture anchor talus (75.3 ± 45.6 N; P = .027) repairs were significantly lower than that of the intact (160.9 ± 72.2 N) ATFL group. Stiffness of the Broström (6.0 ± 2.5 N/mm; P = .02), suture anchor fibula (6.8 N/mm ± 2.7; P = .05), and suture anchor talus (6.6 N/mm ± 4.0; P = .04) repairs were significantly lower than that of the intact (12.4 N/mm ± 4.1 N/mm) ATFL group. The 3 repair groups were not significantly different from each other, but all 3 were substantially lower in strength and stiffness when compared to the intact ATFL. The use of suture anchors to repair the ATFL produces a repair that can withstand loads to failure similar to the suture-only Broström repair. However, all 3 repair groups were much weaker than

Achondroplasia and multiple-suture craniosynostosis.

Science.gov (United States)

Albino, Frank P; Wood, Benjamin C; Oluigbo, Chima O; Lee, Angela C; Oh, Albert K; Rogers, Gary F

2015-01-01

Genetic mutations in the fibroblast growth factor receptor 3 gene may lead to achondroplasia or syndromic forms of craniosynostosis. Despite sharing a common genetic basis, craniosynostosis has rarely been described in cases of confirmed achondroplasia. We report an infant with achondroplasia who developed progressive multiple-suture craniosynostosis to discuss the genetic link between these clinical entities and to describe the technical challenges associated with the operative management.

Numerical test for single concrete armour layer on breakwaters

OpenAIRE

Anastasaki, E; Latham, J-P; Xiang, J

2016-01-01

The ability of concrete armour units for breakwaters to interlock and form an integral single layer is important for withstanding severe wave conditions. In reality, displacements take place under wave loading, whether they are small and insignificant or large and representing serious structural damage. In this work, a code that combines finite- and discrete-element methods which can simulate motion and interaction among units was used to conduct a numerical investigation. Various concrete ar...

Giant magnetoimpedance effect in sputtered single layered NiFe film and meander NiFe/Cu/NiFe film

International Nuclear Information System (INIS)

Chen, L.; Zhou, Y.; Lei, C.; Zhou, Z.M.; Ding, W.

2010-01-01

Giant magnetoimpedance (GMI) effect on NiFe thin film is very promising due to its application in developing the magnetic field sensors with highly sensitivity and low cost. In this paper, the single layered NiFe thin film and NiFe/Cu/NiFe thin film with a meander structure are prepared by the MEMS technology. The influences of sputtering parameters, film structure and conductor layer width on GMI effect in NiFe single layer and meander NiFe/Cu/NiFe film are investigated. Maximum of the GMI ratio in single layer and sandwich film is 5% and 64%, respectively. The results obtained are useful for developing the high-performance magnetic sensors based on NiFe thin film.

Gonioscopy-assisted Transluminal Trabeculotomy (GATT): Thermal Suture Modification With a Dye-stained Rounded Tip.

Science.gov (United States)

Grover, Davinder S; Fellman, Ronald L

2016-06-01

To describe a novel technique for thermally marking the tip of a suture, in preparation for a gonioscopy-assisted transluminal trabeculotomy. One patient was used as an example for this technique. Technique report. The authors introduce a modification of a novel surgical procedure (GATT) in which a suture is marked and thermally blunted allowing a proper visualization while performing an ab interno, minimally invasive, circumferential 360-degree suture trabeculotomy. The authors have previously reported on the GATT surgery with the use of an illuminated microcatheter, which allowed for visualization of the tip of the catheter as it circumnavigated Schlemm canal. This modification allows for similar visualization of the tip of the suture, however, is much more cost-effective while still maintaining similar safety.

Structure and field emission of graphene layers on top of silicon nanowire arrays

International Nuclear Information System (INIS)

Huang, Bohr-Ran; Chan, Hui-Wen; Jou, Shyankay; Chen, Guan-Yu; Kuo, Hsiu-An; Song, Wan-Jhen

2016-01-01

Graphical abstract: - Highlights: • We prepared graphene on top of silicon nanowires by transfer-print technique. • Graphene changed from discrete flakes to a continuous by repeated transfer-print. • The triple-layer graphene had high electron field emission due to large edge ratio. - Abstract: Monolayer graphene was grown on copper foils and then transferred on planar silicon substrates and on top of silicon nanowire (SiNW) arrays to form single- to quadruple-layer graphene films. The morphology, structure, and electron field emission (FE) of these graphene films were investigated. The graphene films on the planar silicon substrates were continuous. The single- to triple-layer graphene films on the SiNW arrays were discontinuous and while the quadruple-layer graphene film featured a mostly continuous area. The Raman spectra of the graphene films on the SiNW arrays showed G and G′ bands with a singular-Lorentzian shape together with a weak D band. The D band intensity decreased as the number of graphene layers increased. The FE efficiency of the graphene films on the planar silicon substrates and the SiNW arrays varied with the number of graphene layers. The turn-on field for the single- to quadruple-layer graphene films on planar silicon substrates were 4.3, 3.7, 3.5 and 3.4 V/μm, respectively. The turn-on field for the single- to quadruple-layer graphene films on SiNW arrays decreased to 3.9, 3.3, 3.0 and 3.3 V/μm, respectively. Correlation of the FE with structure and morphology of the graphene films is discussed.

Structure and field emission of graphene layers on top of silicon nanowire arrays

Energy Technology Data Exchange (ETDEWEB)

Huang, Bohr-Ran; Chan, Hui-Wen [Graduate Institute of Electro-Optical Engineering and Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China); Jou, Shyankay, E-mail: sjou@mail.ntust.edu.tw [Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China); Chen, Guan-Yu [Graduate Institute of Electro-Optical Engineering and Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China); Kuo, Hsiu-An; Song, Wan-Jhen [Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China)

2016-01-30

Graphical abstract: - Highlights: • We prepared graphene on top of silicon nanowires by transfer-print technique. • Graphene changed from discrete flakes to a continuous by repeated transfer-print. • The triple-layer graphene had high electron field emission due to large edge ratio. - Abstract: Monolayer graphene was grown on copper foils and then transferred on planar silicon substrates and on top of silicon nanowire (SiNW) arrays to form single- to quadruple-layer graphene films. The morphology, structure, and electron field emission (FE) of these graphene films were investigated. The graphene films on the planar silicon substrates were continuous. The single- to triple-layer graphene films on the SiNW arrays were discontinuous and while the quadruple-layer graphene film featured a mostly continuous area. The Raman spectra of the graphene films on the SiNW arrays showed G and G′ bands with a singular-Lorentzian shape together with a weak D band. The D band intensity decreased as the number of graphene layers increased. The FE efficiency of the graphene films on the planar silicon substrates and the SiNW arrays varied with the number of graphene layers. The turn-on field for the single- to quadruple-layer graphene films on planar silicon substrates were 4.3, 3.7, 3.5 and 3.4 V/μm, respectively. The turn-on field for the single- to quadruple-layer graphene films on SiNW arrays decreased to 3.9, 3.3, 3.0 and 3.3 V/μm, respectively. Correlation of the FE with structure and morphology of the graphene films is discussed.

Single-layer dispersions of transition metal dichalcogenides in the synthesis of intercalation compounds

International Nuclear Information System (INIS)

Golub, Alexander S; Zubavichus, Yan V; Slovokhotov, Yurii L; Novikov, Yurii N

2003-01-01

Chemical methods for the exfoliation of transition metal dichalcogenides in a liquid medium to give single-layer dispersions containing quasi-two-dimensional layers of these compounds are surveyed. Data on the structure of dispersions and their use in the synthesis of various types of heterolayered intercalation compounds are discussed and described systematically. Structural features, the electronic structure and the physicochemical properties of the resulting intercalation compounds are considered. The potential of this method of synthesis is compared with that of traditional solid-state methods for the intercalation of layered crystals.

A Tale of Amalgamation of Three Permo-Triassic Collage Systems in Central Asia: Oroclines, Sutures, and Terminal Accretion

Science.gov (United States)

Xiao, Wenjiao; Windley, Brian F.; Sun, Shu; Li, Jiliang; Huang, Baochun; Han, Chunming; Yuan, Chao; Sun, Min; Chen, Hanlin

2015-05-01

The Central Asian Orogenic Belt records the accretion and convergence of three collage systems that were finally rotated into two major oroclines. The Mongolia collage system was a long, N-S-oriented composite ribbon that was rotated to its current orientation when the Mongol-Okhotsk orocline was formed. The components of the Kazakhstan collage system were welded together into a long, single composite arc that was bent to form the Kazakhstan orocline. The cratons of Tarim and North China were united and sutured by the Beishan orogen, which terminated with formation of the Solonker suture in northern China. All components of the three collage systems were generated by the Neoproterozoic and were amalgamated in the Permo-Triassic. The Central Asian Orogenic Belt evolved by multiple convergence and accretion of many orogenic components during multiple phases of amalgamation, followed by two phases of orocline rotation.

Introduction of a New Suture Method in Repair of Peripheral Nerves Injured with a Sharp Mechanism

Directory of Open Access Journals (Sweden)

Alireza Saied

2015-09-01

Full Text Available Background: The standard method for repair of an injured peripheal nerve is epineural repair with separate sutures. Herein we describe a method in which the nerve is sutured with continous sutures. In fact this method has not been utilized for nerve repair previously and our purpose was to compare it to the standard method. If it proved to be successful it would replace the standard method in certain circumstances. Methods: The proposal of the clinical trial was given a reference number form the ethics comitee. 25 dogs in which the scaitic nerve was cut by a sharp blade under genaeral anesthesia were divided randomly into three groups: control (5 dogs, repair of sciatic nerve with simple sutures (10 and repair with continous sutures (10. In the control group the nerve was not repaired at all. After 6 weeks the dogs were killed and the nerve was studied by light and electronic microscopes. The amount of consumed suture material, time of repair, myelin thickness and axon diiameter were examined. Ultrastructural studies were performed to assess degeneration and regeneration findings. Results: Time of repair and the amount of consumed suture material were significantly lower in the continous group (P

Local Electronic Structure of a Single-Layer Porphyrin-Containing Covalent Organic Framework

KAUST Repository

Chen, Chen; Joshi, Trinity; Li, Huifang; Chavez, Anton D.; Pedramrazi, Zahra; Liu, Pei-Nian; Li, Hong; Dichtel, William R.; Bredas, Jean-Luc; Crommie, Michael F.

2017-01-01

We have characterized the local electronic structure of a porphyrin-containing single-layer covalent organic framework (COF) exhibiting a square lattice. The COF monolayer was obtained by the deposition of 2,5-dimethoxybenzene-1,4-dicarboxaldehyde

Edge structures and properties of triangular antidots in single-layer MoS2

KAUST Repository

Gan, Li Yong; Cheng, Yingchun; Schwingenschlö gl, Udo; Yao, Yingbang; Zhao, Yong; Zhang, Xixiang; Huang, Wei

2016-01-01

Density functional theory and experiments are employed to shed light on the edge structures of antidots in O etched single-layer MoS2. The equilibrium morphology is found to be the zigzag Mo edge with each Mo atom bonded to two O atoms, in a wide range of O chemical potentials. Scanning electron microscopy shows that the orientation of the created triangular antidots is opposite to the triangular shape of the single-layer MoS2 samples, in agreement with the theoretical predictions. Furthermore, edges induced by O etching turn out to be p-doped, suggesting an effective strategy to realize p-type MoS2 devices. Published by AIP Publishing.

Edge structures and properties of triangular antidots in single-layer MoS2

KAUST Repository

Gan, Li Yong

2016-08-30

Density functional theory and experiments are employed to shed light on the edge structures of antidots in O etched single-layer MoS2. The equilibrium morphology is found to be the zigzag Mo edge with each Mo atom bonded to two O atoms, in a wide range of O chemical potentials. Scanning electron microscopy shows that the orientation of the created triangular antidots is opposite to the triangular shape of the single-layer MoS2 samples, in agreement with the theoretical predictions. Furthermore, edges induced by O etching turn out to be p-doped, suggesting an effective strategy to realize p-type MoS2 devices. Published by AIP Publishing.

Structural characterization of amorphous Fe-Si and its recrystallized layers

International Nuclear Information System (INIS)

Naito, Muneyuki; Ishimaru, Manabu; Hirotsu, Yoshihiko; Valdez, James A.; Sickafus, Kurt E.

2006-01-01

We have synthesized amorphous Fe-Si thin layers and investigated their microstructure using transmission electron microscopy (TEM). Si single crystals with (1 1 1) orientation were irradiated with 120 keV Fe + ions to a fluence of 4.0 x 10 17 cm -2 at cryogenic temperature (120 K), followed by thermal annealing at 1073 K for 2 h. A continuous amorphous layer with a bilayered structure was formed on the topmost layer of the Si substrate in the as-implanted specimen: the upper layer was an amorphous Fe-Si, while the lower one was an amorphous Si. After annealing, the amorphous bilayer crystallized into a continuous β-FeSi 2 thin layer

Single-Layer Limit of Metallic Indium Overlayers on Si(111).

Science.gov (United States)

Park, Jae Whan; Kang, Myung Ho

2016-09-09

Density-functional calculations are used to identify one-atom-thick metallic In phases grown on the Si(111) surface, which have long been sought in quest of the ultimate two-dimensional (2D) limit of metallic properties. We predict two metastable single-layer In phases, one sqrt[7]×sqrt[3] phase with a coverage of 1.4 monolayer (ML; here 1 ML refers to one In atom per top Si atom) and the other sqrt[7]×sqrt[7] phase with 1.43 ML, which indeed agree with experimental evidences. Both phases reveal quasi-1D arrangements of protruded In atoms, leading to 2D-metallic but anisotropic band structures and Fermi surfaces. This directional feature contrasts with the free-electron-like In-overlayer properties that are known to persist up to the double-layer thickness, implying that the ultimate 2D limit of In overlayers may have been achieved in previous studies of double-layer In phases.

Anomalous photoluminescence thermal quenching of sandwiched single layer MoS_2

KAUST Repository

Tangi, Malleswararao

2017-09-22

We report an unusual thermal quenching of the micro-photoluminescence (µ-PL) intensity for a sandwiched single-layer (SL) MoS2. For this study, MoS2 layers were chemical vapor deposited on molecular beam epitaxial grown In0.15Al0.85N lattice matched templates. Later, to accomplish air-stable sandwiched SL-MoS2, a thin In0.15Al0.85N cap layer was deposited on the MoS2/In0.15Al0.85N heterostructure. We confirm that the sandwiched MoS2 is a single layer from optical and structural analyses using µ-Raman spectroscopy and scanning transmission electron microscopy, respectively. By using high-resolution X-ray photoelectron spectroscopy, no structural phase transition of MoS2 is noticed. The recombination processes of bound and free excitons were analyzed by the power-dependent µ-PL studies at 77 K and room temperature (RT). The temperature-dependent micro photoluminescence (TDPL) measurements were carried out in the temperature range of 77 – 400 K. As temperature increases, a significant red-shift is observed for the free-exciton PL peak, revealing the delocalization of carriers. Further, we observe unconventional negative thermal quenching behavior, the enhancement of the µ-PL intensity with increasing temperatures up to 300K, which is explained by carrier hopping transitions that take place between shallow localized states to the band-edges. Thus, this study renders a fundamental insight into understanding the anomalous thermal quenching of µ-PL intensity of sandwiched SL-MoS2.

Anomalous photoluminescence thermal quenching of sandwiched single layer MoS_2

KAUST Repository

Tangi, Malleswararao; Shakfa, Mohammad Khaled; Mishra, Pawan; Li, Ming-Yang; Chiu, Ming-Hui; Ng, Tien Khee; Li, Lain-Jong; Ooi, Boon S.

2017-01-01

We report an unusual thermal quenching of the micro-photoluminescence (µ-PL) intensity for a sandwiched single-layer (SL) MoS2. For this study, MoS2 layers were chemical vapor deposited on molecular beam epitaxial grown In0.15Al0.85N lattice matched templates. Later, to accomplish air-stable sandwiched SL-MoS2, a thin In0.15Al0.85N cap layer was deposited on the MoS2/In0.15Al0.85N heterostructure. We confirm that the sandwiched MoS2 is a single layer from optical and structural analyses using µ-Raman spectroscopy and scanning transmission electron microscopy, respectively. By using high-resolution X-ray photoelectron spectroscopy, no structural phase transition of MoS2 is noticed. The recombination processes of bound and free excitons were analyzed by the power-dependent µ-PL studies at 77 K and room temperature (RT). The temperature-dependent micro photoluminescence (TDPL) measurements were carried out in the temperature range of 77 – 400 K. As temperature increases, a significant red-shift is observed for the free-exciton PL peak, revealing the delocalization of carriers. Further, we observe unconventional negative thermal quenching behavior, the enhancement of the µ-PL intensity with increasing temperatures up to 300K, which is explained by carrier hopping transitions that take place between shallow localized states to the band-edges. Thus, this study renders a fundamental insight into understanding the anomalous thermal quenching of µ-PL intensity of sandwiched SL-MoS2.

Layer potentials, Kac's problem, and refined Hardy inequality on homogeneous Carnot groups

OpenAIRE

Ruzhansky, Michael; Suragan, Durvudkhan

2017-01-01

We propose the analogues of boundary layer potentials for the sub-Laplacian on homogeneous Carnot groups/stratified Lie groups and prove continuity results for them. In particular, we show continuity of the single layer potential and establish the Plemelj type jump relations for the double layer potential. We prove sub-Laplacian adapted versions of the Stokes theorem as well as of Green's first and second formulae on homogeneous Carnot groups. Several applications to boundary value problems a...

SR and LR Union Suture for the Treatment of Myopic Strabismus Fixus: Is Scleral Fixation Necessary?

Directory of Open Access Journals (Sweden)

Carol P. S. Lam

2015-01-01

Full Text Available Purpose. To evaluate and compare the effectiveness of scleral fixation SR and LR union suture and nonscleral fixation union suture for the treatment of myopic strabismus fixus. Methods. Retrospective review of 32 eyes of 22 patients with myopic strabismus fixus who had undergone union suture of superior rectus (SR and lateral rectus (LR with or without scleral fixation, and follow-up longer than 6 months at Hong Kong Eye Hospital from 2006 to 2013. Surgical techniques and outcomes in terms of ocular alignment are analyzed. Results. There is significant overall improvement both in postoperative angle of esodeviation (P0.05. Conclusions. Union suture of SR and LR is an effective procedure in correcting myopic strabismus fixus. Fixation of the union suture to the sclera does not improve surgical outcome.

Modified Single Stapler Technique in Anterior Resection for Rectal Cancer

International Nuclear Information System (INIS)

Akbaba, D.; Ersoy, P.E.; Gundogdu, R.H.

2015-01-01

Technical difficulties during colorectal surgery increase the complication rates. We introduce a modified single stapler technique for patients in whom technical problems are encountered while performing double stapler technique. Before pelvic dissection, descending colon is divided at minimum 10 cm proximal to the tumoral segment. Tumor specific mesorectal excision is performed and two purse string sutures are placed at the distal margin with an interval of 1 - 2 cm. After introducing a circular stapler via the anus, the distal purse string suture is tied around the central shaft of the stapler and the proximal purse string suture around the colonic lumen. After the resection is completed between the two sutures, the anvil shaft is connected to the central shaft and the stapler is closed and fired. None of the patients had an anastomotic leak. This technique may be a safe alternative particularly in patients with narrow pelvis and distal tumors. (author)

Images of interlayer Josephson vortices in single-layer cuprates

International Nuclear Information System (INIS)

Moler, K. A.; Kirtley, J. R.; Liang, R.; Bonn, D. A.; Hardy, W. N.; Williams, J. M.; Schlueter, J. A.; Hinks, D.; Villard, G.; Maignan, A.; Nohara, M.; Takagi, H.

2000-01-01

The interlayer penetration depth in layered superconductors may be determined from scanning Superconducting QUantum Interference Device (SQUID) microscope images of interlayer Josephson vortices. The authors compare their findings at 4 K for single crystals of the organic superconductor κ-(BEDT-TTF) 2 Cu(NCS) 2 and three near-optimally doped cuprate superconductors: La 2-x Sr x CuO 4 , (Hg, Cu)Ba 2 CuO 4+δ , and Tl 2 Ba 2 CuO 6+δ

The optimum tension for bridging sutures in transosseous-equivalent rotator cuff repair: a cadaveric biomechanical study.

Science.gov (United States)

Park, Ji Soon; McGarry, Michelle H; Campbell, Sean T; Seo, Hyuk Jun; Lee, Yeon Soo; Kim, Sae Hoon; Lee, Thay Q; Oh, Joo Han

2015-09-01

Transosseous-equivalent (TOE) rotator cuff repair can increase contact area and contact pressure between the repaired cuff tendon and bony footprint and can show higher ultimate loads to failure and smaller gap formation compared with other repair techniques. However, it has been suggested that medial rotator cuff failure after TOE repair may result from increased bridging suture tension. To determine optimum bridging suture tension in TOE repair by evaluating footprint contact and construct failure characteristics at different tensions. Controlled laboratory study. A total of 18 fresh-frozen cadaveric shoulders, randomly divided into 3 groups, were constructed with a TOE configuration using the same medial suture anchor and placing a Tekscan sensing pad between the repaired rotator cuff tendon and footprint. Nine of the 18 shoulders were used to measure footprint contact characteristics. With use of the Tekscan measurement system, the contact pressure and area between the rotator cuff tendon and greater tuberosity were quantified for bridging suture tensions of 60, 90, and 120 N with glenohumeral abduction angles of 0° and 30° and humeral rotation angles of 30° (internal), 0°, and 30° (external). TOE constructs of all 18 shoulders then underwent construct failure testing (cyclic loading and load to failure) to determine the yield load, ultimate load, stiffness, hysteresis, strain, and failure mode at 60 and 120 N of tension. As bridging suture tension increased, contact force, contact pressure, and peak pressure increased significantly at all positions (P .05 for all). Increasing bridging suture tension to over 90 N did not improve contact area but did increase contact force and pressure. Bridging suture tension did not significantly affect ultimate failure loads. Considering the risks of overtensioning bridging sutures, it may be clinically more beneficial to keep bridging suture tension below 90 N. © 2015 The Author(s).

Comparative histology of some craniofacial sutures and skull-base synchondroses in non-avian dinosaurs and their extant phylogenetic bracket.

Science.gov (United States)

Bailleul, Alida M; Horner, John R

2016-08-01

Sutures and synchondroses, the fibrous and cartilaginous articulations found in the skulls of vertebrates, have been studied for many biological applications at the morphological scale. However, little is known about these articulations at the microscopic scale in non-mammalian vertebrates, including extant archosaurs (birds and crocodilians). The major goals of this paper were to: (i) document the microstructure of some sutures and synchondroses through ontogeny in archosaurs; (ii) compare these microstructures with previously published sutural histology (i.e. that of mammals); and (iii) document how these articulations with different morphological degrees of closure (open or obliterated) appear histologically. This was performed with histological analyses of skulls of emus, American alligators, a fossil crocodilian and ornithischian dinosaurs (hadrosaurids, pachycephalosaurids and ceratopsids). Emus and mammals possess a sutural periosteum until sutural fusion, but it disappears rapidly during ontogeny in American alligators. This study identified seven types of sutural mineralized tissues in extant and extinct archosaurs and grouped them into four categories: periosteal tissues; acellular tissues; fibrous tissues; and intratendinous tissues. Due to the presence of a periosteum in their sutures, emus and mammals possess periosteal tissues at their sutural borders. The mineralized sutural tissues of crocodilians and ornithischian dinosaurs are more variable and can also develop via a form of necrosis for acellular tissues and metaplasia for fibrous and intratendinous tissues. It was hypothesized that non-avian dinosaurs, like the American alligator, lacked a sutural periosteum and that their primary mode of ossification involved the direct mineralization of craniofacial sutures (instead of intramembranous ossification found in mammals and birds). However, we keep in mind that a bird-like sutural microstructure might have arisen within non-avian saurichians. While

Catastrophe in the stochastic layer due to dipole perturbation for a single-null divertor Tokamak

International Nuclear Information System (INIS)

Ali, H.; Watson, M.; Punjabi, A.; Boozer, A.

1996-01-01

We use the method of maps developed by Punjabi and Boozer to investigate the motion of magnetic field lines in stochastic scrape-off layer in the presence of dipole perturbation of a single-null divertor Tokamak. This method is based on the idea that the magnetic field line trajectories in a divertor tokamak are mathematically equivalent to a single degree of freedom, time dependent Hamiltonian System, and that the basic features of motion near a separatrix broadened by asymmetric perturbations are generic for such Hamiltonian and near-Hamiltonian systems. The magnetic topology of a single-null divertor tokamak with the effects on dipole perturbations is represented by the Symmetric Simple Map followed by Dipole Map. We have found that as the amplitude of the dipole perturbation increases, the width of the stochastic layer also increases. At some critical value of the amplitude is reached, there is a catastrophic increase in the width of stochastic layer. This may have significant implications for tokamak divertor physics

Experimental studies on the influence of irradiation (60Co) on wound healing of colonic suture

International Nuclear Information System (INIS)

Shoji, Munehiro

1980-01-01

Effects of preoperative 60 Co irradiation on wound healing of colonic suture in adult dogs of mixed breed were discussed. Wound healing 7 days after colonic suture was compared among dogs which received colonic suture immediately, or 3 days, or 7 days after the 60 Co irradiation. As a result, there was not a big difference in their wound healing among these dogs, and disorders of wound healing were not found. Bursting pressure at sutured sites was always lower in irradiated dogs than controls. Recovery of the bursting pressure was 2 days slower in irradiated dogs than non-irradiated dogs for 7 days after the suture. Bursting pressure was the lowest on the 3rd day after the suture in both groups. As to fine changes in irradiated dogs, appearance of recommunicating phenomena in blood vessels, delay of a decrease in avascular regions, delay of granulation, and hypertrophy of vascular walls seemed to be influenced by 60 Co irradiation, but there was not a big difference in these results between irradiated and non-irradiated dogs. An increase in postoperative concentration of hydroproline tended to be little lower in irradiated dogs than controls, which seemed to be influenced by the 60 Co irradiation. This result was also suggested from delay of granulation and remaining inflammations. Effects of 60 Co irradiation on wound healing of colonic suture seemed to be slight generally, because ruptured suture scarecely occurred in the irradiated dogs. When doses used in this experiment were calculated roughly by Ellis's method, irradiation of 60 Co seemed not to influence seriously wound healing if the total of 2,000 to 2,500 rad was irradiated in 8 to 10 doses to human colon. (Tsunoda, M.)

Secretion of wound healing mediators by single and bi-layer skin substitutes.

Science.gov (United States)

Maarof, Manira; Law, Jia Xian; Chowdhury, Shiplu Roy; Khairoji, Khairul Anuar; Saim, Aminuddin Bin; Idrus, Ruszymah Bt Hj

2016-10-01

Limitations of current treatments for skin loss caused by major injuries leads to the use of skin substitutes. It is assumed that secretion of wound healing mediators by these skin substitutes plays a role in treating skin loss. In our previous study, single layer keratinocytes (SK), single layer fibroblast (SF) and bilayer (BL; containing keratinocytes and fibroblasts layers) skin substitutes were fabricated using fibrin that had shown potential to heal wounds in preclinical studies. This study aimed to quantify the secretion of wound healing mediators, and compare between single and bi-layer skin substitutes. Skin samples were digested to harvest fibroblasts and keratinocytes, and expanded to obtain sufficient cells for the construction of skin substitutes. Acellular fibrin (AF) construct was used as control. Substitutes i.e. AF, SK, SF and BL were cultured for 2 days, and culture supernatant was collected to analyze secretion of wound healing mediators via multiplex ELISA. Among 19 wound healing mediators tested, BL substitute secreted significantly higher amounts of CXCL1 and GCSF compared to SF and AF substitute but this was not significant with respect to SK substitute. The BL substitute also secreted significantly higher amounts of CXCL5 and IL-6 compared to other substitutes. In contrast, the SK substitute secreted significantly higher amounts of VCAM-1 compared to other substitutes. However, all three skin substitutes also secreted CCL2, CCL5, CCL11, GM-CSF, IL8, IL-1α, TNF-α, ICAM-1, FGF-β, TGF-β, HGF, VEGF-α and PDGF-BB factors, but no significant difference was seen. Secretion of these mediators after transplantation may play a significant role in promoting wound healing process for the treatment of skin loss.

Continuous-Wave Single-Photon Transistor Based on a Superconducting Circuit

DEFF Research Database (Denmark)

Kyriienko, Oleksandr; Sørensen, Anders Søndberg

2016-01-01

We propose a microwave frequency single-photon transistor which can operate under continuous wave probing and represents an efficient single microwave photon detector. It can be realized using an impedance matched system of a three level artificial ladder-type atom coupled to two microwave cavities...... and the appearance of a photon flux leaving the second cavity through a separate input-output port. The proposal does not require time variation of the probe signals, thus corresponding to a passive version of a single-photon transistor. The resulting device is robust to qubit dephasing processes, possesses low dark...

High quality single atomic layer deposition of hexagonal boron nitride on single crystalline Rh(111) four-inch wafers

Energy Technology Data Exchange (ETDEWEB)

Hemmi, A.; Bernard, C.; Cun, H.; Roth, S.; Klöckner, M.; Kälin, T.; Osterwalder, J.; Greber, T., E-mail: greber@physik.uzh.ch [Physik-Institut, Universität Zürich, CH-8057 Zürich (Switzerland); Weinl, M.; Gsell, S.; Schreck, M. [Institut für Physik, Universität Augsburg, D-86135 Augsburg (Germany)

2014-03-15

The setup of an apparatus for chemical vapor deposition (CVD) of hexagonal boron nitride (h-BN) and its characterization on four-inch wafers in ultra high vacuum (UHV) environment is reported. It provides well-controlled preparation conditions, such as oxygen and argon plasma assisted cleaning and high temperature annealing. In situ characterization of a wafer is accomplished with target current spectroscopy. A piezo motor driven x-y stage allows measurements with a step size of 1 nm on the complete wafer. To benchmark the system performance, we investigated the growth of single layer h-BN on epitaxial Rh(111) thin films. A thorough analysis of the wafer was performed after cutting in atmosphere by low energy electron diffraction, scanning tunneling microscopy, and ultraviolet and X-ray photoelectron spectroscopies. The apparatus is located in a clean room environment and delivers high quality single layers of h-BN and thus grants access to large area UHV processed surfaces, which had been hitherto restricted to expensive, small area single crystal substrates. The facility is versatile enough for customization to other UHV-CVD processes, e.g., graphene on four-inch wafers.

Technique of 'suture less' appendicectomy by laparoscopy in children: Preliminary communication.

Science.gov (United States)

Bajpai, Minu

2014-01-01

Objective of this study is to present our experience by harmonic scalpel enabled, single external port appendicectomy using extracorporeally inserted 'pick and fix' stitch in three cases. Of the eighteen appendicectomies performed with only the use of harmonic scalpel in the last 11 months, the last three were performed using a single external port with the second port accessed under the subcutaneous tissues. The procedure consists of anchoring the mesoappendix to anterior abdominal wall by an extracorporeally inserted 'pick and fix' stitch followed by dissection and division of mesoappendix and appendix only with harmonic scalpel. There were three patients, one female and two males aged 5, 7, and 11 years, respectively. Two were elective and one was emergency appendicectomy. Mean operating time was 30 min without any surgical complications. All patients are in follow-up with no complications. This study demonstrates the combined virtue of single external port, use of harmonic scalpel, and 'pick and fix' suture in laparoscopic appendicectomy in children. This approach avoids the use of an additional port as well as endosuture; and is safe, efficient, cost-effective, and is associated with reduced surgical time.

A Novel Clinical-Simulated Suture Education for Basic Surgical Skill: Suture on the Biological Tissue Fixed on Standardized Patient Evaluated with Objective Structured Assessment of Technical Skill (OSATS) Tools.

Science.gov (United States)

Shen, Zhanlong; Yang, Fan; Gao, Pengji; Zeng, Li; Jiang, Guanchao; Wang, Shan; Ye, Yingjiang; Zhu, Fengxue

2017-06-21

Clinical-simulated training has shown benefit in the education of medical students. However, the role of clinical simulation for surgical basic skill training such as suturing techniques remains unclear. Forty-two medical students were asked to perform specific suturing tasks at three stations with the different settings within four minutes (Station 1: Synthetic suture pad fixed on the bench, Station 2: Synthetic suture pad fixed on the standardized patient, Station 3: Pig skin fixed on the standardized patient); the OSATS (Objective Structured Assessment of Technical Skill) tool was used to evaluate the performance of students. A questionnaire was distributed to the students following the examination. Mean performance score of Station 3 was significant lower than that of Station 1 and 2 in the general performance including tissue handling, time, and motion. The suturing techniques of students at Station 2 and 3 were not as accurate as that at Station 1. Inappropriate tension was applied to the knot at Station 2 compared with Station 1 and 3. On the questionnaire, 93% of students considered clinical-simulated training of basic surgical skills was necessary and may increase their confidence in future clinical work as surgeons; 98% of students thought the assessment was more objective when OSATS tool was used for evaluation. Clinical simulation examination assessed with OSATS might throw a novel light on the education of basic surgical skills and may be worthy of wider adoption in the surgical education of medical students.

Outcome of strabismus surgery by nonadjustable suture among ...

African Journals Online (AJOL)

Outcome of strabismus surgery by nonadjustable suture among adults attending a ... postoperative residual deviation, 83 patients (86%) had defective vision with amblyopia. ... Conclusion: Surgical treatment of strabismus in Saudi adult with ...

Surgical suture braided with a diclofenac-loaded strand of poly(lactic-co-glycolic acid) for local, sustained pain mitigation.

Science.gov (United States)

Huh, Beom Kang; Kim, Byung Hwi; Kim, Se-Na; Park, Chun Gwon; Lee, Seung Ho; Kim, Ka Ryeong; Heo, Chan Yeong; Choy, Young Bin

2017-10-01

In this work, we propose a surgical suture that can sustainably release diclofenac (DF) for the local pain relief of surgical wounds. We separately fabricated a DF-loaded strand composed of a biodegradable polymer, poly(lactic-co-glycolic acid) (PLGA), which was then braided with a surgical suture already in clinical use, i.e., VICRYL™. In this way, the drug-delivery suture presented herein could release DF in a sustained manner for 10days while maintaining the mechanical strength needed for wound closure. According to the in vivo results of an induced-pain animal model, the drug-delivery suture mitigated pain throughout the period of persistent pain. The histological analysis of tissue around the sutures showed that the drug-delivery suture exhibited biocompatibility comparable to that of the VICRYL™ suture in clinical use. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of efficacy of polypropylene with chromic catgut suture in stitching paediatric facial lacerations

International Nuclear Information System (INIS)

Hussain, A.; Ahmed, R.; Aziz, O.B.A.; Aamir, M.

2016-01-01

Objective: The objective of this study was to compare 5/0 polypropylene suture with 5/0 chromic catgut in small clean pediatric facial laceration repair in terms of cosmetic outcome. Study Design: Randomized controlled trial.Place and Duration of Study: Combined Military Hospital, Rawalpindi from 26th May 2012 to 25th Nov 2012.Patients and Methods: A total of 300 patients of both gender under 12 years of age, with small clean facial lacerations were selected and divided in two equal groups using random number tables. All the patients underwent suturing in minor operating theater of trauma centre CMH Rawalpindi as day care cases, under local anesthesia and aseptic measures. In group 1, polypropylene 5/0 suture was used where as in group 2 chromic catgut 5/0 was used for suturing. Aseptic dressing was applied. All patients were reviewed on 5th day (for stitch removal in polypropylene group) and 3 months post-operatively to establish cosmetic outcome which was determined by scar visual analog score both by parents of the child and consultant surgeon. Results: The mean VAS (visual analog score) as observed by Consultant surgeon was 79.14 and 78.63 for polypropylene and chromic catgut groups respectively. The mean VAS observed by the parents of the child for respective groups was 76.67 and 76.03. The significance value was 0.961 for parental VAS and 0.988 for surgeons VAS depicting insignificant difference in both suture groups.Conclusion: There is no long-term difference in cosmetic outcomes of both the sutures in the repair of facial lacerations in the pediatric population. No difference in complication rate of wound was observed. In addition, the parents of the children in absorbable suture group expressed satisfaction over prevention of psychological trauma of stitch removal. (author)

A learning rule for very simple universal approximators consisting of a single layer of perceptrons.

Science.gov (United States)

Auer, Peter; Burgsteiner, Harald; Maass, Wolfgang

2008-06-01

One may argue that the simplest type of neural networks beyond a single perceptron is an array of several perceptrons in parallel. In spite of their simplicity, such circuits can compute any Boolean function if one views the majority of the binary perceptron outputs as the binary output of the parallel perceptron, and they are universal approximators for arbitrary continuous functions with values in [0,1] if one views the fraction of perceptrons that output 1 as the analog output of the parallel perceptron. Note that in contrast to the familiar model of a "multi-layer perceptron" the parallel perceptron that we consider here has just binary values as outputs of gates on the hidden layer. For a long time one has thought that there exists no competitive learning algorithm for these extremely simple neural networks, which also came to be known as committee machines. It is commonly assumed that one has to replace the hard threshold gates on the hidden layer by sigmoidal gates (or RBF-gates) and that one has to tune the weights on at least two successive layers in order to achieve satisfactory learning results for any class of neural networks that yield universal approximators. We show that this assumption is not true, by exhibiting a simple learning algorithm for parallel perceptrons - the parallel delta rule (p-delta rule). In contrast to backprop for multi-layer perceptrons, the p-delta rule only has to tune a single layer of weights, and it does not require the computation and communication of analog values with high precision. Reduced communication also distinguishes our new learning rule from other learning rules for parallel perceptrons such as MADALINE. Obviously these features make the p-delta rule attractive as a biologically more realistic alternative to backprop in biological neural circuits, but also for implementations in special purpose hardware. We show that the p-delta rule also implements gradient descent-with regard to a suitable error measure

On the approximation by single hidden layer feedforward neural networks with fixed weights

OpenAIRE

Guliyev, Namig J.; Ismailov, Vugar E.

2017-01-01

International audience; Feedforward neural networks have wide applicability in various disciplines of science due to their universal approximation property. Some authors have shown that single hidden layer feedforward neural networks (SLFNs) with fixed weights still possess the universal approximation property provided that approximated functions are univariate. But this phenomenon does not lay any restrictions on the number of neurons in the hidden layer. The more this number, the more the p...

A prospective outcome and cost-effectiveness comparison between two ligament reattachment techniques using suture anchors for chronic ankle instability.

Science.gov (United States)

Cho, Byung-Ki; Kim, Yong-Min; Park, Kyoung-Jin; Park, Ji-Kang; Kim, Do-Kyoon

2015-02-01

There are various ligament reattachment techniques for the modified Brostrom procedure. There have been few comparative studies on recently developed techniques. This prospective study was performed to compare the functional outcomes of 2 different ligament reattachment techniques using suture anchors. We furthermore evaluated the cost-effectiveness of the suture bridge technique. Forty-five amateur athletes under 30 years of age were followed for more than 2 years. Twenty-four procedures with the suture anchor technique and 21 procedures with the suture bridge technique were performed by one surgeon. The functional evaluation consisted of the American Orthopaedic Foot & Ankle Society (AOFAS) score, Foot and Ankle Outcome Score (FAOS), Karlsson score, Sefton grading system, and the period to return to various forms of exercise (jogging, spurt running, jumping, one leg standing for >1 minute, walking on uneven ground, and going down stairs). Measurement of talar tilt angle and anterior talar translation was obtained from stress radiographs to evaluate mechanical stability. There were no significant differences on AOFAS score, FAOS, Karlsson score, Sefton grade, and stress radiographs. There were no significant differences on the return to exercises, except for jumping. As the most common complication, there were 3 cases of skin irritation by suture materials in the suture anchor group and 2 cases of intraoperative breakage of the suture anchor in suture bridge group. Both ligament reattachment techniques using suture anchors showed similar functional outcomes. Considering the additional medical expenses incurred by more suture anchors, the modified Brostrom procedure using the suture bridge technique had low cost-effectiveness. Proper indication and clinical usefulness of suture bridge technique for chronic ankle instability will be addressed in further studies. Level II, prospective comparative study. © The Author(s) 2014.

Solid oxide fuel cell cathode with oxygen-reducing layer

Science.gov (United States)

Surdoval, Wayne A.; Berry, David A.; Shultz, Travis

2018-04-03

The disclosure provides a SOFC comprised of an electrolyte, anode, and cathode, where the cathode comprises an MIEC and an oxygen-reducing layer. The oxygen-reducing layer is in contact with the MIEC, and the MIEC is generally between and separating the oxygen-reducing layer and the electrolyte. The oxygen-reducing layer is comprised of single element oxides, single element carbonates, or mixtures thereof, and has a thickness of less than about 30 nm. In a particular embodiment, the thickness is less than 5 nm. In another embodiment, the thickness is about 3 monolayers or less. The oxygen-reducing layer may be a continuous film or a discontinuous film with various coverage ratios. The oxygen-reducing layer at the thicknesses described may be generated on the MIEC surface using means known in the art such as, for example, ALD processes.

Arthroscopic repair of lateral ankle ligament complex by suture anchor.

Science.gov (United States)

Wang, Jingwei; Hua, Yinghui; Chen, Shiyi; Li, Hongyun; Zhang, Jian; Li, Yunxia

2014-06-01

Arthroscopic repair of the lateral ligament complex with suture anchors is increasingly used to treat chronic ankle instability (CAI). Our aims are (1) to analyze and evaluate the literature on arthroscopic suture anchor repair of the anterior talofibular ligament and (2) to conduct a systematic review of the clinical evidence on the reported outcomes and complications of treating CAI with this technique. We performed a systematic review of the literature using PubMed, Ovid, Elsevier ScienceDirect, Web of Science-Conference Proceedings Citation Index, and the Cochrane Database of Systematic Reviews from 1987 to September 2013. Clinical studies using the arthroscopic suture anchor technique to treat CAI were included. Outcome measures consisted of clinical assessment of postoperative ligament stability and complications. In addition, the methodologic quality of the included studies was assessed by use of the modified Coleman Methodology Score. After reviewing 371 studies, we identified 6 studies (5 retrospective case series and 1 prospective case series, all Level IV) that met the inclusion criteria, with a mean Coleman Methodology Score of 71.8 ± 7.52 (range, 63 to 82). In these studies 178 patients (179 ankles) underwent arthroscopic suture anchor repair of the anterior talofibular ligament with a mean follow-up period of 38.9 months (range, 6 to 117.6 months). All patients were reported to have subjective improvement of their ankle instability, with complications in 31 cases. Studies of arthroscopic suture anchor technique to treat CAI are sparse, with moderate mean methodologic quality. The included studies suggest that the arthroscopic technique is a feasible procedure to restore ankle stability; however, on the basis of our review, this technique seems to be associated with a relatively high complication rate. Extensive cadaveric studies, clinical trials, and comparative studies comparing arthroscopic and open repair should be performed in the future. Level

Single-layer Ultralight, Flexible, Shielding Tension Shell System for Extreme Heat and Radiation

Data.gov (United States)

National Aeronautics and Space Administration — The objective of this project is to develop a flexible thermal protection system (FTPS) with a Boron Nitride Nanotube (BNNT)-based single-layer, lightweight,...

Single-layer model for surface roughness.

Science.gov (United States)

Carniglia, C K; Jensen, D G

2002-06-01

Random roughness of an optical surface reduces its specular reflectance and transmittance by the scattering of light. The reduction in reflectance can be modeled by a homogeneous layer on the surface if the refractive index of the layer is intermediate to the indices of the media on either side of the surface. Such a layer predicts an increase in the transmittance of the surface and therefore does not provide a valid model for the effects of scatter on the transmittance. Adding a small amount of absorption to the layer provides a model that predicts a reduction in both reflectance and transmittance. The absorbing layer model agrees with the predictions of a scalar scattering theory for a layer with a thickness that is twice the rms roughness of the surface. The extinction coefficient k for the layer is proportional to the thickness of the layer.

Simulation study on single event burnout in linear doping buffer layer engineered power VDMOSFET

International Nuclear Information System (INIS)

Jia Yunpeng; Su Hongyuan; Hu Dongqing; Wu Yu; Jin Rui

2016-01-01

The addition of a buffer layer can improve the device's secondary breakdown voltage, thus, improving the single event burnout (SEB) threshold voltage. In this paper, an N type linear doping buffer layer is proposed. According to quasi-stationary avalanche simulation and heavy ion beam simulation, the results show that an optimized linear doping buffer layer is critical. As SEB is induced by heavy ions impacting, the electric field of an optimized linear doping buffer device is much lower than that with an optimized constant doping buffer layer at a given buffer layer thickness and the same biasing voltages. Secondary breakdown voltage and the parasitic bipolar turn-on current are much higher than those with the optimized constant doping buffer layer. So the linear buffer layer is more advantageous to improving the device's SEB performance. (paper)

Visibility of sutures of the orbit and periorbital region using multidetector computed tomography

Energy Technology Data Exchange (ETDEWEB)

Gufler, Hubert; Preis, Markus; Koesling, Sabrina [Dept. of Diagnostic Radiology, Martin-Luther-University Halle-Wittenberg, Halle (Germany)

2014-12-15

Knowledge of cranial suture morphology is crucial in emergency medicine, forensic medicine, and maxillofacial reconstructive surgery. This study assessed the visibility of sutures of the orbit and periorbital region on multidetector computed tomography. Multidetector computed tomography scans of 200 patients (127 males, 73 females; mean age 51.3 years; range, 6-92 years) were evaluated retrospectively. The slice thicknesses varied from 0.5 to 1 mm, and the tube current from 25 to 370 mAs, depending on the CT indication. The visibility of sutures was estimated according to a 4-point scale from 'not visible to well visible' The chi-squared test was used to test the association of the visibility of sutures with the slice thickness, tube current, and age of patients. Statistical significance was assumed at p < 0.05. Overall, best visibility was found for the sutura frontozygomatica (98%), sutura frontonasalis (88.5%), and sutura sphenozygomatica (71.5%), followed by the sutura zygomaticomaxillaris (65.8%), sutura temporozygomatica (41.8%), sutura frontomaxillaris (44.5%), and sutura sphenofrontalis (31%). Poor visibility was found for the sutura frontolacrimalis (16.8%) and sutura frontoethmoidalis (1.3%). The sutura ethmoidomaxillaris, sutura lacrimomaxillaris, and sutura ethmoidolacrimalis were not visible. Although the sutures of the superior, lateral, and inferior orbit are well visible, those of the medial orbit are poorly visible on CT scans.

LED phototherapy on midpalatal suture after rapid maxilla expansion: a Raman spectroscopic study

Science.gov (United States)

Rosa, Cristiane B.; Habib, Fernando Antonio L.; de Araújo, Telma M.; dos Santos, Jean N.; Cangussu, Maria Cristina T.; Barbosa, Artur Felipe S.; de Castro, Isabele Cardoso V.; Soares, Luiz Guilherme P.; Pinheiro, Antonio L. B.

2015-03-01

A quick bone formation after maxillary expansion would reduce treatment timeand the biomodulating effects of LED light could contribute for it. The aim of this study was to analyze the effect of LED phototherapy on the acceleration of bone formation at the midpalatal suture after maxilla expansion. Thirty rats divided into 6 groups were used on the study at 2 time points - 7 days: Control; Expansion; and Expansion + LED; and 14 days: Expansion; Expansion + LED in the first week; Expansion and LED in the first and second weeks. LED irradiation occurred at every 48 h during 2 weeks. Expansion was accomplished using a spatula and maintained with a triple helicoid of 0.020" stainless steel orthodontic wire. A LED light (λ850 ± 10nm, 150mW ± 10mW, spot of 0.5cm2, t=120 sec, SAEF of 18J/cm2) was applied in one point in the midpalatal suture immediately behind the upper incisors. Near infrared Raman spectroscopic analysis of the suture region was carried and data submitted to statistical analyzes (p≤0.05). Raman spectrum analysis demonstrated that irradiation increased hydroxyapatite in the midpalatal suture after expansion. The results of this indicate that LED irradiation; have a positive biomodulation contributing to the acceleration of bone formation in the midpalatal suture after expansion procedure.

Edge structures and properties of triangular antidots in single-layer MoS{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Gan, Li-Yong, E-mail: ganly@swjtu.edu.cn, E-mail: iamyccheng@njtech.edu.cn, E-mail: udo.schwingenschlogl@kaust.edu.sa [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Center, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Cheng, Yingchun, E-mail: ganly@swjtu.edu.cn, E-mail: iamyccheng@njtech.edu.cn, E-mail: udo.schwingenschlogl@kaust.edu.sa; Huang, Wei [Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials - SICAM, Nanjing Tech University - NanjingTech, 30 South Puzhu Road, Nanjing 211816 (China); Schwingenschlögl, Udo, E-mail: ganly@swjtu.edu.cn, E-mail: iamyccheng@njtech.edu.cn, E-mail: udo.schwingenschlogl@kaust.edu.sa [Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900 (Saudi Arabia); Yao, Yingbang [Advanced Nanofabrication and Imaging Core Lab, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900 (Saudi Arabia); School of Materials and Energy, Guangdong University of Technology, Guangdong 510006 (China); Zhao, Yong [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Center, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); School of Physical Science and Technology, Southwest Jiaotong University, Chengdu, 610031 Sichuan (China); Zhang, Xi-xiang [Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900 (Saudi Arabia); Advanced Nanofabrication and Imaging Core Lab, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900 (Saudi Arabia)

2016-08-29

Density functional theory and experiments are employed to shed light on the edge structures of antidots in O etched single-layer MoS{sub 2}. The equilibrium morphology is found to be the zigzag Mo edge with each Mo atom bonded to two O atoms, in a wide range of O chemical potentials. Scanning electron microscopy shows that the orientation of the created triangular antidots is opposite to the triangular shape of the single-layer MoS{sub 2} samples, in agreement with the theoretical predictions. Furthermore, edges induced by O etching turn out to be p-doped, suggesting an effective strategy to realize p-type MoS{sub 2} devices.

A Comfortable Solution To Tracheal Anastomosis Protection: Tracheal Retention Sutures.

Science.gov (United States)

Karapolat, Sami; Turkyilmaz, Atila; Seyis, Kubra Nur; Tekinbas, Celal

2018-04-01

Fixation of the chin to the anterior chest wall is the most commonly used method of reducing anastomotic tension following a segmental resection of the trachea and reconstruction with primary anastomosis. However, the sutures required for this method may lead to various organic and psychological problems. In five patients who underwent tracheal resection and primary anastomosis, retention sutures were placed on the proximal and distal-lateral edges of the anastomotic line rather than placing a Guardian chin stitch. All patients were mobilised in the early postoperative period and were able to perform their routine daily activities without restrictions. During their average 14.4 months of follow-up, no complications were found in their anastomotic lines during their clinical, radiological, and bronchoscopic assessments. The placement of tracheal retention sutures proved an inexpensive and reliable method to reduce anastomotic tension without additional surgical burden, and was effective in terms of patient comfort. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Single-unit-cell layer established Bi 2 WO 6 3D hierarchical architectures: Efficient adsorption, photocatalysis and dye-sensitized photoelectrochemical performance

Energy Technology Data Exchange (ETDEWEB)

Huang, Hongwei; Cao, Ranran; Yu, Shixin; Xu, Kang; Hao, Weichang; Wang, Yonggang; Dong, Fan; Zhang, Tierui; Zhang, Yihe

2017-12-01

Single-layer catalysis sparks huge interests and gains widespread attention owing to its high activity. Simultaneously, three-dimensional (3D) hierarchical structure can afford large surface area and abundant reactive sites, contributing to high efficiency. Herein, we report an absorbing single-unit-cell layer established Bi2WO6 3D hierarchical architecture fabricated by a sodium dodecyl benzene sulfonate (SDBS)-assisted assembled strategy. The DBS- long chains can adsorb on the (Bi2O2)2+ layers and hence impede stacking of the layers, resulting in the single-unit-cell layer. We also uncovered that SDS with a shorter chain is less effective than SDBS. Due to the sufficient exposure of surface O atoms, single-unit-cell layer 3D Bi2WO6 shows strong selectivity for adsorption on multiform organic dyes with different charges. Remarkably, the single-unit-cell layer 3D Bi2WO6 casts profoundly enhanced photodegradation activity and especially a superior photocatalytic H2 evolution rate, which is 14-fold increase in contrast to the bulk Bi2WO6. Systematic photoelectrochemical characterizations disclose that the substantially elevated carrier density and charge separation efficiency take responsibility for the strengthened photocatalytic performance. Additionally, the possibility of single-unit-cell layer 3D Bi2WO6 as dye-sensitized solar cells (DSSC) has also been attempted and it was manifested to be a promising dye-sensitized photoanode for oxygen evolution reaction (ORR). Our work not only furnish an insight into designing single-layer assembled 3D hierarchical architecture, but also offer a multi-functional material for environmental and energy applications.

Hydrogen intercalation of single and multiple layer graphene synthesized on Si-terminated SiC(0001) surface

International Nuclear Information System (INIS)

Sołtys, Jakub; Piechota, Jacek; Ptasinska, Maria; Krukowski, Stanisław

2014-01-01

Ab initio density functional theory simulations were used to investigate the influence of hydrogen intercalation on the electronic properties of single and multiple graphene layers deposited on the SiC(0001) surface (Si-face). It is shown that single carbon layer, known as a buffer layer, covalently bound to the SiC substrate, is liberated after hydrogen intercalation, showing characteristic Dirac cones in the band structure. This is in agreement with the results of angle resolved photoelectron spectroscopy measurements of hydrogen intercalation of SiC-graphene samples. In contrast to that hydrogen intercalation has limited impact on the multiple sheet graphene, deposited on Si-terminated SiC surface. The covalently bound buffer layer is liberated attaining its graphene like structure and dispersion relation typical for multilayer graphene. Nevertheless, before and after intercalation, the four layer graphene preserved the following dispersion relations in the vicinity of K point: linear for (AAAA) stacking, direct parabolic for Bernal (ABAB) stacking and “wizard hat” parabolic for rhombohedral (ABCA) stacking

A tight-binding model of the transmission probability through a molecular junction; a single molecule vs. a molecular layer

International Nuclear Information System (INIS)

Landau, A.; Nitzan, A.

2006-01-01

Full Text: Molecular electronics, one of the major fields of the current effort in nano-science, may be de ed as the study of electronic behaviors, devices and applications that depend on the properties of matter at the molecular scale. If the miniaturization trend of microelectronic devices is to continue, elements such as transistors and contacts will soon shrink to single molecules. The promise of these new technological breakthroughs has been major driving force in this ld. Moreover, the consideration of molecular systems as electronic devices has raised new fundamental questions. In particular, while traditional quantum chemistry deals with electronically closed systems, we now face problems involving molecular systems that are open to their electronic environment, moreover, function in far from equilibrium situations. A generic molecular junction is made of two electrodes connected by a molecular spacer that takes the form of a molecular chain of varying length or a molecular layer of varying thickness. We use a simple nearest-neighbors tight-biding model with the non-equilibrium Green's function (NEGF) method to investigate and compare between a self-assembled monolayer (SAM), finite molecular layer (FML), and single molecule (SM) chemisorption to a surface of a metal substrate. In addition, we examine the difference in the transmission probability through a SAM, FML and SM sandwiched between two metallic electrodes. Dramatic differences are observed between the SM, FML and SAM density of electronic states and transmission functions. In addition, we analyze the effects of changing different physical parameters such as molecule-substrate interaction, molecule-molecule interactions, etc; interesting effects that pertain to the conduction properties of single molecules and molecular layers are observed. Intriguing results are attained when we investigate the commensurability of the SAM with the metallic surface

Suture, synthetic, or biologic in contaminated ventral hernia repair.

Science.gov (United States)

Bondre, Ioana L; Holihan, Julie L; Askenasy, Erik P; Greenberg, Jacob A; Keith, Jerrod N; Martindale, Robert G; Roth, J Scott; Liang, Mike K

2016-02-01

Data are lacking to support the choice between suture, synthetic mesh, or biologic matrix in contaminated ventral hernia repair (VHR). We hypothesize that in contaminated VHR, suture repair is associated with the lowest rate of surgical site infection (SSI). A multicenter database of all open VHR performed at from 2010-2011 was reviewed. All patients with follow-up of 1 mo and longer were included. The primary outcome was SSI as defined by the Centers for Disease Control and Prevention. The secondary outcome was hernia recurrence (assessed clinically or radiographically). Multivariate analysis (stepwise regression for SSI and Cox proportional hazard model for recurrence) was performed. A total of 761 VHR were reviewed for a median (range) follow-up of 15 (1-50) mo: there were 291(38%) suture, 303 (40%) low-density and/or mid-density synthetic mesh, and 167(22%) biologic matrix repair. On univariate analysis, there were differences in the three groups including ethnicity, ASA, body mass index, institution, diabetes, primary versus incisional hernia, wound class, hernia size, prior VHR, fascial release, skin flaps, and acute repair. The unadjusted outcomes for SSI (15.1%; 17.8%; 21.0%; P = 0.280) and recurrence (17.8%; 13.5%; 21.5%; P = 0.074) were not statistically different between groups. On multivariate analysis, biologic matrix was associated with a nonsignificant reduction in both SSI and recurrences, whereas synthetic mesh associated with fewer recurrences compared to suture (hazard ratio = 0.60; P = 0.015) and nonsignificant increase in SSI. Interval estimates favored biologic matrix repair in contaminated VHR; however, these results were not statistically significant. In the absence of higher level evidence, surgeons should carefully balance risk, cost, and benefits in managing contaminated ventral hernia repair. Copyright © 2016 Elsevier Inc. All rights reserved.

Four-Strand Core Suture Improves Flexor Tendon Repair Compared to Two-Strand Technique in a Rabbit Model

Directory of Open Access Journals (Sweden)

Alice Wichelhaus

2016-01-01

Full Text Available Introduction. This study was designed to investigate the influence of the amount of suture material on the formation of peritendinous adhesions of intrasynovial flexor tendon repairs. Materials and Methods. In 14 rabbits, the flexor tendons of the third and the fourth digit of the right hind leg were cut and repaired using a 2- or 4-strand core suture technique. The repaired tendons were harvested after three and eight weeks. The range of motion of the affected toes was measured and the tendons were processed histologically. The distance between the transected tendon ends, the changes in the peritendinous space, and cellular and extracellular inflammatory reaction were quantified by different staining. Results. A 4-strand core suture resulted in significantly less gap formation. The 2-strand core suture showed a tendency to less adhesion formation. Doubling of the intratendinous suture material was accompanied by an initial increase in leukocyte infiltration and showed a greater amount of formation of myofibroblasts. From the third to the eighth week after flexor tendon repair, both the cellular and the extracellular inflammation decreased significantly. Conclusion. A 4-strand core suture repair leads to a significantly better tendon healing process with less diastasis between the sutured tendon ends despite initially pronounced inflammatory response.

Single-layer centrifugation through colloid selects improved quality of epididymal cat sperm.

Science.gov (United States)

Chatdarong, K; Thuwanut, P; Morrell, J M

2010-06-01

The objectives were to determine the: 1) extent of epithelial and red blood cell contamination in epididymal cat sperm samples recovered by the cutting method; 2) efficacy of simple washing, single-layer centrifugation (SLC), and swim-up for selecting epididymal cat sperm; and 3) effects of freezing and thawing on cat sperm selected by various techniques. Ten unit samples were studied; each contained sperm from the cauda epididymides of four cats (total, approximately 200 x 10(6) sperm) and was equally allocated into four treatments: 1) simple washing, 2) single-layer centrifugation through colloid prior to cryopreservation (SLC-PC), 3) single-layer centrifugation through colloid after cryopreservation (SLC-AC), and 4) swim-up. Centrifugation (300 x g for 20 min) was done for all methods. The SLC-PC had a better recovery rate than the SLC-AC and swim-up methods (mean+/-SD of 16.4+/-8.7, 10.7+/-8.9, and 2.3+/-1.7%, respectively; Pblood cell contamination than simple washed samples (0.02+/-0.01, 0.02+/-0.04, 0.03+/-0.04, and 0.44+/-0.22 x 10(6) cells/mL, respectively; P0.05), SLC-PC yielded the highest percentage of sperm with normal midpieces and tails (P0.05). In conclusion, both SLC-PC and swim-up improved the quality of epididymal cat sperm, including better morphology, membrane and DNA integrity, and removal of cellular contamination. However, SLC had a better sperm recovery rate than swim-up. 2010 Elsevier Inc. All rights reserved.

Healing of the suture line in the irradiated small intestine