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1.
A cohort of 39 patients (28 male, 11 female) that had undergone total meniscectomy as adolescents (mean age 16 years) underwent FISP 3D Magnetic Resonance Imaging at a mean follow up of 30 years. The presence of meniscal tissue was assessed by two independent observers blinded to the operation details. The volume of any meniscal tissue present was calculated. A posterior horn remnant was seen in 57% of medial and 45% of lateral meniscectomy cases. The mean volume of an operated medial meniscal remnant was 0.29 mL compared with a mean volume of 1.15 mL for an intact medial meniscus. The mean volume of an operated lateral meniscal remnant was 0.30 mL compared with 1.07 mL for an intact lateral meniscus. We have shown that the incidence of incomplete excision of the posterior horn is more common after total medial meniscectomy, and that at a mean follow up of 30 years there is no convincing in vivo MRI evidence of long-term meniscal regeneration.  相似文献   
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Neural Computing and Applications - Cryptography often involves substituting (and converting) the secret information into dummy data so that it could reach the desired destination without leakage....  相似文献   
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Neural Computing and Applications - Emperor Penguin Optimizer (EPO) is a recently developed metaheuristic algorithm to solve general optimization problems. The main strength of EPO is twofold....  相似文献   
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The magnitude of precipitation plays an important role in the yield and supply of terrigenous matter into the sea through fluvial supply. The influence of climate on the influx of total suspended matter (TSM) into the continental margin of the SE Arabian Sea has been evaluated from subweekly synoptic variations in TSM and its advection rates, currents and winds during the southwest monsoon (SWM) and postmonsoon season. Our study endorses the high influx of TSM during the SWM (>82 mg l?1; advection 26–110 mg m?2 s?1), albeit that most of it is sequestered into the shallow coastal region. Over the mid-outer shelf, there is uniformly low TSM (12–24 mg l?1) and a weak TSM advection (9–4 mg m?2 s?1) throughout the year. This trend is persistent also in areas having upwelling-induced high marine productivity. We therefore surmise that higher fluvial influx and primary production during the SWM do not necessarily enhance the supply of particulate matter into the deeper offshore regions of the SE Arabian Sea. We ascribe a vital role to the prevailing morphodynamic processes.  相似文献   
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A new material, which can be used in solar energy utilization, is obtained here by adding different weights of poly(vinyl alcohol) (PVA) to the semiconducting material CdS. The effect of this addition was studied by using FT‐Raman spectrometer (based on 1500 mW Nd : YAG laser at 1064 nm), UV–Vis‐IR (190–800 nm) spectrophotometer, and X‐ray diffractometer. Our experimental results indicated the appearance of several new Raman bands, which have not existed in both CdS and PVA. Some of the bands which are already existing in the Raman spectra of PVA showed an unexpected systematic increase in their intensities after the addition of CdS to the matrix. On the other hand, some of the new Raman bands appeared in special concentrations of PVA only, whereas some of the Raman bands of CdS were found to disappear after adding PVA. Finally, shifts in some bands associated with random increase in their intensities after adding PVA to CdS was detected in the FT‐Raman analysis. The experimental evidence given here might be attributed to the occurrence of new bonds, indicating that the produced mixture is a new material. The assignment of the new bands as well as an interpretation of the obtained variations is given here. Our X‐ray diffraction data confirmed the interpretation introduced here. Moreover, the UV–Vis spectra confirmed the existence of new absorption bands in the Visible region. The I‐V characteristic curve was measured for a selected concentration of the new composite material, showing a remarkable increase in the values of the conduction current of about two orders of magnitude as compared with the pure PVA material. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1984–1992, 2004  相似文献   
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A new single crystal of cesium sulphate-doped 4-methoxyaniline (CS-4MOA) was obtained by the solvent evaporation approach. XRD manifests that the CS-4MOA crystallizes in orthorhombic crystal structure. The existence of several functional groups in the CS-4MOA crystal is affirmed by FTIR analysis. SEM-EDAX analysis was performed to examine the surface morphology and the composition of CS-4MOA sample. Ultraviolet–visible spectral study validates the transparency of CS-4MOA in the region of 330–1100 nm. The thermal steadiness of the CS-4MOA crystal was examined using TG/DTA, which revealed that it was stable up to 88 °C. The mechanical stability of CS-4MOA crystal was assessed through Vickers microhardness analysis. VSM analysis was used to evaluate the magnetic behaviour of the CS-4MOA crystal. The electrical characteristics of the CS-4MOA were investigated by impedance study for various temperatures. The NLO parameters of CS-4MOA were computed by Z-scan technique. The existence of second order nonlinear optical susceptibility in CS-4MOA was confirmed by the SHG investigation. Additionally, antimicrobial activity of CS-4MOA was performed against bacterial strains and fungal pathogen for medicinal applications.

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Newly proposed polymer electrolyte membranes (PEMs) composed of an electrospun poly(vinylidene fluoride) (PVDF) fibrous mat embedded in a poly(4‐vinylpyridine) (P4VP) matrix were successfully fabricated in order to improve the mechanical and dimensional stabilities and ionic conductivity of membranes in lithium rechargeable batteries. Fourier transform infrared spectroscopic analysis showed that as a result of the use of a high voltage during electrospinning the crystalline structure of PVDF changed partially from α‐phase to β‐phase. Energy‐dispersive X‐ray spectroscopy confirmed the existence of crosslinked P4VP in the PVDF fibrous mat. The electrolyte uptakes of PVDF and PVDF/P4VP composite mats were higher than that of PVDF cast film. The tensile properties of PVDF/P4VP composite mat were considerably improved compared to those of the pristine PVDF fibrous mat under both dry and wet (soaked with electrolyte) conditions. In addition, the mechanical and dimensional stabilities of the PVDF/P4VP composite PEM were further enhanced due to crosslinking between the P4VP chains. Furthermore, the PVDF/P4VP composite PEM exhibited an ionic conductivity that was an order of magnitude higher than that of traditional PVDF film. © 2012 Society of Chemical Industry  相似文献   
10.
Polymer Light Emitting Diodes (PLEDs), the most promising name in the field of display technology has received tremendous attention from various research groups. The research on light emitting polymers are an interdisciplinary zone which has challenging investigates on materials science and engineering, physics of device architecture and technology. This review addresses the wide range of tailored polymers, evolution of LED device structure for high performance, single and multicolor polymer based LEDs. Though, polymers are possessing better efficiency and easy fabrication processes, it has very low stability and short life. This study also reviews, device degradation during device fabrication and operation.  相似文献   
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