Intracorneal ring segment

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Visual rehabilitation in moderate keratoconus: combined corneal wavefront-guided transepithelial photorefractive keratectomy and high-fluence accelerated corneal collagen cross-linking after intracorneal ring segment implantation

Visual rehabilitation in moderate keratoconus: combined corneal wavefront-guided transepithelial photorefractive keratectomy and high-fluence accelerated corneal collagen cross-linking after intracorneal ring segment implantation

Visual rehabilitation has been accomplished through differ- ent combinations of intracorneal ring segment (ICRS) im- plantations, CXL, and/or photorefractive keratectomy (PRK) for keratoconic patients. ICRS implantations act by flattening the central cornea without affecting the corneal visual axis [17, 18]. They have been reported to be effective in reducing mean keratometry values, coma aberrations, and corneal astigmatism [19 – 21]. Several studies have evaluated the ef- fects of combined CXL and ICRS implantation in patients with keratoconus, and have shown overall additive effects on visual acuity and keratometry values [22, 23]. Combined PRK and CXL have also been used for the treatment of kera- toconus [24–27]. A study investigating the effect of topography-guided PRK and CXL after ICRS implantation in patients with low to moderate keratoconus has demon- strated that uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), keratometry values, and coma aberrations were significantly improved at 6-months postoperatively [28]. Additionally, Coskunseven et al. have reported that, in patients with progressive keratoco- nus, topography-guided tPRK, after ICRS implantation and followed by CXL, resulted in an improvement in logMAR UDVA, logMAR CDVA, manifest refraction spherical equivalent (MRSE), and mean steep and flat keratometry values [29]. Recently, Zeraid et al. have shown similar results for logMAR UDVA and keratometry values, but demon- strated no significant reduction in coma aberrations after ICRS implantation followed by same-day topography-guided PRK and CXL [30]. Another study has reported that the combination of accelerated CXL and same-day transepithe- lial phototherapeutic keratectomy and single inferior ICRS is as effective as the combined treatment, using standard CXL, in terms of visual and topographical outcomes [9].
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Visual perception changes and optical stability after intracorneal ring segment implantation: comparison between 3 months and 1 year after surgery

Visual perception changes and optical stability after intracorneal ring segment implantation: comparison between 3 months and 1 year after surgery

For all surgeries the 160 ° Keraring (Mediphacos, Belo Horizonte, Brazil) was implanted with thickness varying from 150 to 350 µ m. Vigamox solution (moxifloxacin HCl ophthalmic solution 0.5%, Alcon Inc, Fort Worth, TX) was instilled 4 times, 1 hour before surgery, and pilocarpine (pilocarpine hydrochloride 10 mg/mL, Allergan Inc, Irvine, CA) once before surgery. The surgery was performed under topical anesthesia (proxymetacaine chlorhydrate 0.5%, Anestalcon, Alcon). Polyvinylpyrrolidone-iodine (PVPI, Ophthalmos, Inc, São Paulo, Brazil) was used over the conjunctiva and cornea 5 minutes before surgery. A circular marker centered on the reflex of microscope light on the cornea was used to create 2 concentric circles of 5 and 7 mm. A radial incision set at 80% of the corneal pachymetry at the steepest corneal axis was made, then 1 or 2 concentric stromal tunnels with an internal radius of 2.5 mm and an attempted extension of 170 ° were constructed with an appropriate curved spatula, and the ring segments implanted in these tunnels. After surgery patients were instructed to use topical antibiotics and corticosteroids (Vigamox eyedrops 3 times a day for 7 days and prednisolone acetate 1%, Falcon, 4 times a day for 10 days).
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Combined femtosecond laser-assisted intracorneal ring segment implantation and corneal collagen cross-linking for correction of keratoconus

Combined femtosecond laser-assisted intracorneal ring segment implantation and corneal collagen cross-linking for correction of keratoconus

The topical antibiotic moxifloxacin (Vigamox, Alcon Laboratories, Inc., Fort Worth, TX, USA), steroids (prednisolone; PredForte, Allergan, Westport, Ireland), and artificial tears were used postoperatively. The artificial eye drops were used every hour during the first day, and then every 4 hours for 1 month. The antibiotic dose timing was every hour for the first day, which then decreased to once every 4 hours for 10 days. The systemic analgesic indomethacin (Cataflam, Novartis, Basel, Switzerland) was prescribed to manage pain due to CXL. Patients were instructed to avoid eye rubbing. Contact lenses were removed once epithelial healing was complete. This usually occurred on the third day after surgery. All patients were examined for a complete ophthalmological test, including BCVA, refrac- tion, and Scheimpflug imaging with the Pentacam at 1, 3, and 6 months, postoperatively. Anterior segment OCT was done only once during follow-up at 1 week to detect ICRS depth and position (Figure 1B). All complications, if any, were documented.
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Femtosecond-assisted intracorneal ring segment complications in keratoconus: from novelty to expertise

Femtosecond-assisted intracorneal ring segment complications in keratoconus: from novelty to expertise

varied from ,1 week to 2 months postoperatively, depending on the infecting organism. Two eyes encountered infection after trivial trauma to the eye and the other two eyes had no predisposing factor. Culture from the conjunctival sac and cornea was positive in two cases with Staphylococcus aureus, while the other two came with pseudomonas sp. They were treated by topical and subconjunctival antibiotics with irri- gation of the channel by antibiotics. Two eyes responded to treatment, while in the other two eyes, ring explantation was the management of choice (Figure 2). One eye proceeded to corneal melting despite ring removal. Healing in all cases ended by opacification along the tunnel (Figure 2C). Crys- talline sterile keratitis (Figure 3) along the inner side of the created tunnel was noticed in three eyes (0.48%).
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The Largest Left Quotient Ring of a Ring

The Largest Left Quotient Ring of a Ring

In general, for a ring R, its left (right; two sided) localizations, especially maximal ones, are unrelated. The intuition behind the construction of the largest strong left quotient ring of R is to have the largest possible left localization of R that is related to all maximal left localizations of the ring R, i.e. there exists a ring R-homomorphism (necessarily, unique) from Q s

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Type conditions of stable range for identification of qualitative generalized classes of rings

Type conditions of stable range for identification of qualitative generalized classes of rings

Proposition 2. Let R be a commutative ring and a is a (von Neumann) regular element of R. Then a = eu, where e ∈ B (R) and u ∈ U (R). Proof. Let axa = a. This implies that axax = ax, i.e. e = ax ∈ B (R) and e ∈ aR. Since axa = a, then ea = a, i.e. a ∈ eR and we have aR = eR.

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Effective ring

Effective ring

Throughout this paper all rings will be commutative with nonzero identity. We say that R is a Bezout ring if every finitely generated ideal of R is principal. A nonzero element a in R is said to be adequate to the element b ∈ R ( a A b denote this fact), if we can find such two elements

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A comparative study of the visual outcomes of Penetrating keratoplasty and deep anterior lamellar Keratoplasty in keratoconus

A comparative study of the visual outcomes of Penetrating keratoplasty and deep anterior lamellar Keratoplasty in keratoconus

Keratoconus, a progressive non inflammatory ectatic disorder of the cornea, mainly has its onset during puberty and progresses during second to third decade of life. Keratoconus causes visual morbidity in young people. The refractive error caused by the ectasia of the cornea is usually successfully treated with contact lenses. While RGP contact lenses remain the contact lens of choice, the newer contact lens design for keratoconus like Rose K lens, hybrid contact lens have improved the compliance of the patient for contact lens. Newer treatment modalities for keratoconus like corneal collagen cross linkage, intracorneal ring segments, phakic intraocular lens implantation, help to stabilize the vision and delay the need for keratoplasty surgery.
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Heterologous Packaging Signals on Segment 4, but Not Segment 6 or Segment 8, Limit Influenza A Virus Reassortment

Heterologous Packaging Signals on Segment 4, but Not Segment 6 or Segment 8, Limit Influenza A Virus Reassortment

The NA segment with heterologous packaging signals is not disfavored during reassortment. Based on low sequence identity in the packaging signal regions (see Table 1), we hypothesized that introduction of NLPS sequences onto the P99 NA segment would disfavor its incorporation, as was seen for HA. However, contrary to our hypothesis, we did not see a significant difference in the incorporation of NA_P99PS versus NA_NLPS (Fig. 6). Coinfections of MDCK cells, genotyping of virus isolates, and enumeration of the NA_PS segments present in the cells at 12 h p.i. were carried out as described for the HA segment above. For the NA_PS viruses, a 1:1 input ratio of VAR to WT viruses in the control coinfection yielded approximately a 50:50 distribution of WT and VAR for each segment as expected (black bars in Fig. 6). However, a 1:1 input ratio of VAR to WT viruses in the heterologous coinfection showed an overrepresen- tation of VAR across all eight segments (gray bars, Fig. 6A), even though there were equal amounts of NA_P99PS and NA_NLPS segments available in the cells at 12 h p.i. (Fig. 6B). As explained above, we expected to see approximately a 50:50 distribution of WT and VAR in all unmodified segments for the heterologous coinfection, since all unmodified segments have P99 packaging signals. Therefore, we repeated the heter- ologous coinfection experiments using a 1:1.5 input ratio of VAR to WT viruses. After this correction, we saw approximately a 50:50 distribution of WT and VAR across the unmodified segments as expected (gray bars, Fig. 6C). Focusing on the NA segment, we observed a slight preference for incorporation of the segment containing matched packaging signals, but this bias was not significant (Fig. 6C). We observed 1.5-fold more NA_NLPS than NA_P99PS available in the cells at 12 h p.i. (Fig. 6D), reflecting the adjusted WT input. Taken together, these data suggest that packaging signal diver- gence on the NA segment does not significantly affect reassortment outcomes be- tween the IAV strains tested.
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On the Lie ring of derivations of a semiprime ring

On the Lie ring of derivations of a semiprime ring

Throughout the text R stands for an associative ring (possibly without identity) and n for a positive integer. By Z(R) we denote the center of R. The ring R is called semiprime, if it has no nonzero nilpotent ideals. Equivalently, aRa = {0} with any a ∈ R implies a = 0. We refer the reader to [1] for terminology, definitions and basic facts in ring theory.

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What is a segment?

What is a segment?

Animals have been described as segmented for more than 2,000 years, yet a precise definition of segmentation remains elusive. Here we give the history of the definition of segmentation, followed by a discussion on current controversies in defining a segment. While there is a general consensus that segmentation involves the repetition of units along the anterior-posterior (a-p) axis, long-running debates exist over whether a segment can be composed of only one tissue layer, whether the most anterior region of the arthropod head is considered segmented, and whether and how the vertebrate head is segmented. Additionally, we discuss whether a segment can be composed of a single cell in a column of cells, or a single row of cells within a grid of cells. We suggest that ‘ segmentation ’ be used in its more general sense, the repetition of units with a-p polarity along the a-p axis, to prevent artificial classification of animals. We further suggest that this general definition be combined with an exact description of what is being studied, as well as a clearly stated hypothesis concerning the specific nature of the potential homology of structures. These suggestions should facilitate dialogue among scientists who study vastly differing segmental structures.
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The Segment Routing Architecture

The Segment Routing Architecture

Segment Routing is a flexible and scalable architecture aimed at supporting the evolving requirements of carrier-grade networks towards application-centric, cloud-based services. In this paper, we provided an introduction to the SR architecture, highlighting its simplicity, and scaling properties. We then dis- cussed various use cases stemming from the network operator community, evolving SR towards a scalable, manageable, yet flexible platform for the provision of new features. We covered use cases such as Traffic Engineering, showing that SR gives fine-grained control over paths without increasing control- plane overhead at transit nodes. Service Function Chaining has been illustrated using SR as a way to execute a service chain without impacting data-plane resource availability. Finally, we showed how these networking features can be made resilient by relying on the basic building blocks of the architecture. Note that SR is a realistic and pragmatic project, with imple- mentations having been recently released.
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AX49 01C MPM periphIO Jul82 pdf

AX49 01C MPM periphIO Jul82 pdf

USER-RING I/O SYSTEM COMMANDS To write out a tape for example, reel 50015 from the segment >udd>Work>Green>data, issue the following commands at Multics command level: io call attach tap[r]

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The Hierarchy of Segment Reports

The Hierarchy of Segment Reports

Besides the strategy as a tool for creating the hierarchy, the manner in which the revenues are logically gen- erated can be used as the second principle for defining the hierarchy. For example, products are sold to cus- tomers. Due to this, the product cannot be higher than the customer in hierarchy. Products are sold to customers not the opposite, leading to a conclusion that the product is a more basic business segment. The creation of a product or a service demands the expenses. Selling the product to the customer will also mean new expenses connected with customers such as exposure in the shop or promotional effort. These are customer specific and not product specific expenses. Since the product is sold to the customers, it leads to a conclusion that the product is a more basic element in the hierarchy. Considering the introduced princi- ples of way the revenues are generated and three levels of the strategy, the proposal of the segment hier- archy can be introduced.
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A morphic ring of neat range one

A morphic ring of neat range one

Since uR + cR = R, we obtain ceβ = e, for some element β ∈ R/sR. Similarly, (1 − c)α(1 − e) = 1 − e for some element α ∈ R/sR. We proved that for any element c = c + sR there exists an idempotent e such that e ∈ cR and 1 − e ∈ (1 − cR). We have proved that R/sR is a clean ring [6] which completes the proof.

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EXPERIMENTAL ANALYSIS OF PISTON RING TO REDUCE FRICTION BY USING DIFFERENT LUBRICANTS (SAE15W and SAE30W) FOR A FOUR STROKE FOUR CYLINDER PETROL ENGINE

EXPERIMENTAL ANALYSIS OF PISTON RING TO REDUCE FRICTION BY USING DIFFERENT LUBRICANTS (SAE15W and SAE30W) FOR A FOUR STROKE FOUR CYLINDER PETROL ENGINE

of the Premier-Padmini 4-stroke SI engine has been considered for the present study. The existing piston ring in the above mentioned setup has rectangular cross section and is made of nodular cast iron.An attempt was made to study the effect of variation in piston ring geometry or the friction by considering parabolic ring made of same material.

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Information Fusion for Hazard Analysis in Multi-Sensor Systems based on Bayesian Networks

Information Fusion for Hazard Analysis in Multi-Sensor Systems based on Bayesian Networks

The Bayesian network for information fusion is defined completely now. With the help of the preprocessed sensor signals the probability for a hand at different positions on the work bench of the sliding table saw can be calculated. Now only an interpretation of the results to operate the warning light and the emergency break have to be added. Therefore two additional nodes (”warning” and ”stop”) are added to the graph. These nodes are not part of the Bayesian network. The node ”warning”’ represents the decision if the hand is in danger and the user shall be warned by lightening warning lights. The node ”stop” stands for activation of the emergency stop. The node ”warning” or ”stop” gets active, if the probability for the state hand of one of the adjacent nodes exceeds the value of 0.5 for a warning and 0.4 for the emergency stop. The adjacent nodes for the ”warning” are as you can see in Figure 8 ”yellow zone back”, ”safety segment 1 left”, ”safety segment 1 right”, ”safety segment 2 left” and ”safety segment 2 right”. The adjacent nodes for the node ”stop” are ”safety segment 3 left” and ”safety segment 3 right”.
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MUCOID IMPACTION OF THE BRONCHI IN CYSTIC FIBROSIS

MUCOID IMPACTION OF THE BRONCHI IN CYSTIC FIBROSIS

tion of the anterior segment (right upper lobe), lateral segment (right middle lobe), and anterior basal segment (right lower lobe). The beginning[r]

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Spatial mapping and quantification of developmental branching morphogenesis

Spatial mapping and quantification of developmental branching morphogenesis

The segmented skeleton is overlaid on the filtered scan data, and a star-convex fill is used to propagate outwards from the central skeleton to the boundaries of the local tubular volume, which is defined by the background level intensity used in the cropping process and is limited by the maximum feature diameter setting. This generates a binary volume surrounding the segmented skeleton and voxels are segmented into zones based on the nearest skeletal voxels, which are pseudo-coloured (Fig. 1B) and quantified to provide the total volume of each segment. Splines are then derived from the skeleton voxels using a recursive least squares fit of a spline of a degree proportional to the number of skeletal voxels in the segment scaled for minimum feature size and limited to ten control points. At the terminal points of the tree (where the skeleton ends centrally in the tip), the spline is extended to reach the volume surface boundary (Fig. 1B). Measurement of splines is more accurate than estimating metrics from a coarse binary voxel skeleton, as splines are smooth and measurements are performed at sub-voxel precision. All length, local angle and curvature data are directly derived from the smooth 3D splines, which describe more accurately the ‘biological’ shapes of the branches of such organs. Determination of diameter also relies on the use of splines, where the spline is traced at 0.1 voxel precision along the length of the spine and the diameter detected by testing the distance from the spline to the surface from a normal vector. Individual angles from the incident are measured for the start direction of each segment (given by the first derivative of the spline). For bifurcations, this is the angle between the start direction of two splines coincident at a branch point (local bifurcation) or relative to the next branch or terminal point (global angle). Where present, dihedral angles are measured between two successive sets of bifurcations. Planes are fitted to the direction vectors of the two splines coincident at a branch point, and then again at the parent bifurcation branch point (local dihedral angle). The dihedral angle is the angle of rotation between these two planes. The same measurement is repeated but using directions to the next branch of terminal point (global dihedral angle). Curvature is measured as the average per- unit-length acceleration of a particle following the trajectory of a spline.
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Analytical study of pseudoexfoliation syndrome, its association with glaucoma and its surgical complications

Analytical study of pseudoexfoliation syndrome, its association with glaucoma and its surgical complications

126 LIST OF ABBREVIATIONS CTR -Capsular Tension Ring CTS - Capsular Tension Segment IOP - Intraocular Pressure SICS- Small Incision Cataract surgery PCR -Posterior capsular rent PEX- Pse[r]

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