Background: The disc prolapse is a common condition especially in young adults. Different levels are affected in the lumber region; the L4/L5 disc is more susceptible to longitudinal load and is the most common site of lumbar disc prolapse. The L5/S1 disc is protected from torsion load by strong ilio-lumbar ligaments but it is more susceptible to axial compressive forces. Many factors affect the result and outcome of surgery in these levels.Objective: The aim of this study is to correlate operative data, short-term results, complications, and prognostic factors (age, gender, mobility, hospital stay, and level of pain) for one-level lumber discectomybetween different levels (L4–L5 vs. L5–S1).Methods In this prospective study, 32 patientsin Al-Yarmouk teaching hospital undergoing survey form March 2008-December 2012.Six patients were excluded from this study because they were diabetics and multilevel disc degeneration .Fifteen (57.6%) patients undergoL5-S1 discectomy and 11 (42.4%) patients undergoL4-5 discectomy. Questionnaires for leg and back pain intensity (Visual Analogue Scale ;VAS), duration of leg pain, and disability (Oswestry Disability Index; ODI), were obtained preoperatively, 3 months, 6 months, 1-year- and 2 year follow-up.Analyses were utilized to evaluate the relationship between surgical outcomes and variable (gender, age, lumber segment, pre-operative ODI, and pre-operative VAS).Results: Mean operative time was[73.44 ± 26.25] min, mean hospital stay was [3-7] days, and mean mobilitywas [2.55 ± 0.93] days. At 2-year follow up, patients revealed a statistical significant improvement inVAS pain (P < 0.05), and ODI lumbar function (P < 0.05).The complications rate were 20.3 %.Our study elaborates good results for one-segmental L5-S1overL4-L5 discectomy. Discectomy of the L4–L5 disc wasassociated with an increased risk of complication (P < 0.05). The comparison revealed that operative time was influenced by age (P = 0.034); hospital stay was influenced by level (P = 0.036) and pre-op VAS (P = 0.006); while complications were influenced by level (P = 0.001) and pre-op ODI (P = 0.049Conclusion: The study revealed significant results for L5-S1 discectomy over L4-L5 discectomy in the late follow up period; the complications rate were higher in L4-L5 level discectomy
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the first part of the research involves investigate the aspect of the radiation superposed on the one bright soliton pulse propagated on ideal single mode
Quantum channels enable the achievement of communication tasks inaccessible to their
classical counterparts. The most famous example is the distribution of secret keys. Unfortunately, the rate
of generation of the secret key by direct transmission is fundamentally limited by the distance. This limit
can be overcome by the implementation of a quantum repeater. In order to boost the performance of the
repeater, a quantum repeater based on cut-off with two different types of quantum memories is suggestd,
which reduces the effect of decoherence during the storage of a quantum state.
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Finding the shortest route in wireless mesh networks is an important aspect. Many techniques are used to solve this problem like dynamic programming, evolutionary algorithms, weighted-sum techniques, and others. In this paper, we use dynamic programming techniques to find the shortest path in wireless mesh networks due to their generality, reduction of complexity and facilitation of numerical computation, simplicity in incorporating constraints, and their onformity to the stochastic nature of some problems. The routing problem is a multi-objective optimization problem with some constraints such as path capacity and end-to-end delay. Single-constraint routing problems and solutions using Dijkstra, Bellman-Ford, and Floyd-Warshall algorith
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In Incremental sheet metal forming process, one important step is to produce tool path, an
accurate tool path is one of the main challenge of incremental sheet metal forming
process. Various factors should be considered prior to generation of the tool path i.e.
mechanical properties of sheet metal, the holding mechanism, tool speed, feed rate and
tool size. In this work investigation studies have been carried out to find the different tool
path strategies to control the twist effect in the final product manufactured by single point
incremental sheet metal forming (SPIF), an adaptive tool path strategy was proposed and
examined for several Aluminum conical models. The comparison of the proposed tool path with t
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Quantum key distribution (QKD) provides unconditional security in theory. However, practical QKD systems face challenges in maximizing the secure key rate and extending transmission distances. In this paper, we introduce a comparative study of the BB84 protocol using coincidence detection with two different quantum channels: a free space and underwater quantum channels. A simulated seawater was used as an example for underwater quantum channel. Different single photon detection modules were used on Bob’s side to capture the coincidence counts. Results showed that increasing the mean photon number generally leads to a higher rate of coincidence detection and therefore higher possibility of increasing the secure key rate. The secure key rat
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Background: Orthodontic tooth movement is characterized by tissue reactions, which consist of an inflammatory response in periodontal ligament and followed by bone remodeling in the periodontium depending on the forces applied. These processes trigger the secretion of various proteins and enzymes into the saliva.The purpose of this study was to evaluate the activity of alkaline phosphatase (ALP) in saliva during orthodontic tooth movement using different magnitude of continuous orthodontic forces. Materials and Methods: Thirty orthodontic patients (12 males and 18 females) aged 17-23 years with class II division I malocclusion all requiring bilateral maxillary first premolar extractions were randomly divided into three groups according to t
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