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We have studied the effect of the thickness of catalytic Ni film for the growth of vertically aligned carbon nanofibers (VA-CNFs) on glass substrates coated with a conductive underlayer of Cr. Both the pretreatment process through which the catalytic Ni nanoparticles were formed and the growth of well-aligned CNFs were carried out in an inductively coupled plasma chemical vapor deposition (ICP-CVD) system. The VA-CNFs were characterized by scanning electron microscopy, Raman spectroscopy, as well as field emission measurements. The results of VA-CNF growth shows that as the Ni film thicknesses decrease, not only the length but also the density of the CNFs drop, although the density of catalytic Ni nanoparticles increases. The variation of CNF density with Ni film thicknesses is believed to be a result of the detachment of the CNFs from the substrate, caused by the electrostatic force produced by the plasma sheath electric field, as well as an ion-enhanced chemical etching effect due to atomic/ionic hydrogen, during the ICP-CVD growth. A field emission measurement apparatus based on a metallic probe of spherical anode structure was also constructed in this study. An electrostatic image model was employed to determine the electric field distribution on the cathode surface. Along with the standard F-N field emission model, the dependence of field emission current density on the cathode surface electric field, as well as an effective field enhancement factor, were extracted from the current-voltage measurement results. The threshold electric field (Ethreshold, for a current density of 1 mA/cm2) increases from 9.2 V/μm to 13.1 V/μm, and then drops to 11.5 V/μm for the CNFs with Ni film thicknesses of 20 nm, 30 nm, and 40 nm, respectively. The electrostatic model results also indicate that the 20 nm case has the greatest space-charge effect on the emission current, consistent with the growth results that the 20 nm case has the lowest CNF density. On the other hand, the CNF length of the 40 nm case is longer than that of the 30 nm one, while the densities are nearly the same; as a result, Ethreshold for the 30 nm case is higher. [ABSTRACT FROM AUTHOR]

Investigation on effects of temperature and HRT on the anaerobic biodegradation of an industrial waste leachate was carried out to improve the performance of an unstable field anaerobic process operated at the ambient temperatures. Maximum biodegradable COD fraction of the leachate was 36% at the mesophilic temperature. Stable COD removal at 35 deg.C was at least 1.2 to 1.4 times higher than those at the ambient temperatures, depending upon HRT. Temperature increase of the field anaerobic process to the mesophilic range was believed to be a competitive and practical option for the performance improvement. (c) 1997 IAWQ. Published by Elsevier Science Ltd. [ABSTRACT FROM AUTHOR]

Aim: To present magnetic resonance imaging (MRI) findings of non-traumatic peroneal nerve palsy and to evaluate the usefulness of MRI in patients with non-traumatic peroneal nerve palsy., Materials and Methods: In a retrospective study, 11 consecutive patients presenting with peroneal nerve palsy were included. MR images of the lower leg and electrophysiological examinations were also reviewed. The cause of peroneal nerve palsy was determined on the basis of MRI findings and was evaluated using electrophysiological data. Nine patients with causative lesions detected on MRI, underwent surgery., Results: Clinical examination and electromyography (EMG) disclosed 11 peroneal lesions. MRI and EMG revealed three types of signal intensity change, i.e. deep peroneal nerve palsy type, common peroneal nerve palsy type, and superficial peroneal nerve palsy type. The MRI and EMG findings were in agreement in seven (65%) of the 11 study patients. In nine patients the causative lesions were identified using MRI, including ganglion cyst (n=6), osteochondroma (n=1), synovial cyst (n=1), and aneurysm (n=1)., Conclusion: Ganglion cyst is the most common cause of non-traumatic peroneal nerve palsy. MRI offers a noninvasive method for obtaining useful information to assess, localize, and monitor peripheral peroneal nerve palsy.

Although myxoid liposarcoma is a subtype of liposarcoma, it may be difficult to establish the correct diagnosis with magnetic resonance (MR) imaging due to the lack of fat signal intensity. Without the administration of gadolinium contrast material, the tumor may even mimic a cystic tumor. A spectrum of MR imaging abnormalities occur in myxoid liposarcoma, depending on the amount of fat and myxoid material, the degree of cellularity and vascularity, and the presence of necrosis. Most myxoid liposarcomas have lacy or linear, amorphous foci of fat. Some myxoid liposarcomas appear to be cystic at nonenhanced MR imaging, although they enhance like other solid masses at contrast material-enhanced MR imaging. The enhancing areas within the tumor represent increased cellularity and vascularity; the nonenhancing areas represent necrosis, reduced cellularity, and accumulated mucinous material. Gadolinium-enhanced imaging is important in differentiating myxoid liposarcoma from benign cystic tumors. Characterization of the tumor with MR imaging plays an important role in the management of myxoid liposarcoma.

We undertook this work to compare the treatment efficacies and the changes of quality of life after pelvic floor muscle (PFM) exercise and the functional electrical stimulation (FES)-biofeedback treatment, both of which are being widely used as conservative treatment methods for female urinary incontinence. We randomly selected 60 female incontinence patients who visited our department and divided them evenly into two groups. They were treated for a period of 6 weeks. The subjective changes in the severity of incontinence and discomfort in daily and social life were measured using a translated version of the questionnaire by Jackson. Objective changes of pelvic muscle contraction force were measured using a perineometer. Pre- and post-treatment maximal pelvic floor muscle contractile (PMC) pressure and changes in the severity of urinary incontinence and discomfort of the two groups showed statistically significant differences (p<0.001). In particular the FES-biofeedback group showed significantly increased maximal PMC pressure and a decreased severity of urinary incontinence and discomfort compared to the intensive PFM exercise group (p<0.001). In conclusion, FES-biofeedback proved more effective than simple PFM exercise.

This study's purpose was to compare the treatment efficacy and the effects on the patients' quality of life of the pelvic floor muscle (PFM) exercise and the functional electrical stimulation (FES)-biofeedback method. Ninety female incontinence patients were randomly selected and evenly divided into three groups: control, intensive PFM exercise, and FES-biofeedback groups. They were treated for 6 weeks. The subjective changes in the severity of incontinence and discomfort in daily and social life were measured using a translated version of Jackson's Bristol female urinary symptom questionnaire. Objective changes of pelvic muscle contraction force were measured by perineometer. Pre and post-treatment maximal pelvic floor muscle contractile pressure (PMC pressure) among the three groups showed statistically significant differences (p < 0.001). Especially the FES-biofeedback group showed significantly increased maximal PMC pressure compared with other groups (p < 0.001). From the questionnaire, pre and post-treatment changes in the severity of urinary incontinence and discomfort due to incontinence showed significant differences among the three groups (p < 0.001). The level of discomfort in daily life, social activity, physical activity, personal relations and discomfort due to urinary symptoms had largely changed and the FES-biofeedback group, in particular, showed a significant decrease after treatment. In conclusion, when PFM exercise and FES-biofeedback were compared in terms of their effects on the patients' quality of life, FES-biofeedback proved to be more effective than verbal explanation or simple PFM exercise.

We report a case of insufficiency fracture of the sternum in a 70-year-old female patient with a review of the literature. She complained of sudden onset chest pain and aggravating dyspnea. She has been managed with corticosteroid due to chronic obstructive pulmonary disease for 15 years. Diagnosis of sternal insufficiency fracture presented with thoracic kyphosis was made on the basis of absence of trauma history, radiologic findings of lateral chest radiograph, bone scintigraphy and chest computed tomography. Thoracic kyphosis and osteoporosis secondary to menopause, corticosteroid therapy and limited mobility due to chronic obstructive pulmonary disease were considered as predisposing factors of the sternal insufficiency fracture in this patient.

The purpose of this study was to evaluate the sequential signal intensity changes in post-traumatic vertebral compression fractures of varying ages. Sixty-six patients with 115 post-traumatic vertebral compression fractures underwent MR imaging. The ages of fractures at the time of MR images ranged from 1 day to 6 years. Sequential follow-up MR imagings were obtained in 4 patients for 2 years after initial MR examination. The fracture sites in all 52 fractures with traumatic events less than 3 months prior were hypointense on T1-weighted images and hyperintense on T2-weighted images (type I). A type I fracture could be subdivided into 3 patterns depending on its morphologic appearance: diffuse (type Ia); patchy (type Ib); and bandlike (type Ic). In 12 fractures of 3 to 5 months after trauma, six showed focal hypointensity (type II) in all pulse sequences, and six showed isointensity (type IV). Four of 51 fractures with trauma over 5 months showed focal hyperintensity on T1-weighted images and isointensity on T2-weighted images (type III); and the remaining 47 fractures showed isointensity on all sequences (type IV). In conclusion, MR imaging is useful in predicting the age of known traumatic compression fractures, so familiarity with these sequential MR findings would be helpful in distinguishing benign from malignant fractures.