Transport of magnetic flux and mass in Saturn's inner magnetosphere

It is well accepted that cold plasma sourced by Enceladus is ultimately lost to the solar wind, while the magnetic flux convecting outward with the plasma must return to the inner magnetosphere. However, whether the interchange or reconnection, or a combination of the two processes is the dominant mechanism in returning the magnetic flux is still under debate. Initial Cassini observations have shown that the magnetic flux returns in the form of flux tubes in the inner magnetosphere. Here we investigate those events with 10 year Cassini magnetometer data and confirm that their magnetic signatures are determined by the background plasma environments: inside (outside) the plasma disk, the returning magnetic field is enhanced (depressed) in strength. The distribution, temporal variation, shape, and transportation rate of the flux tubes are also characterized. The flux tubes break into smaller ones as they convect in. The shape of their cross section is closer to circular than fingerlike as produced in the simulations based on the interchange mechanism. In addition, no sudden changes in any flux tube properties can be found at the “boundary” which has been claimed to separate the reconnection and interchange-dominant regions. On the other hand, reasonable cold plasma loss rate and outflow velocity can be obtained if the transport rate of the magnetic flux matches the reconnection rate, which supports reconnection alone as the dominant mechanism in unloading the cold plasma from the inner magnetosphere and returning the magnetic flux from the tail

Clinical and radiographic investigation of the adjunctive effects of a low-power he-ne laser in the treatment of moderate to advanced periodontal disease: A pilot study

Objective: To evaluate the adjunctive effect of a low-power He-Ne laser in the non-surgical periodontal treatment of patients with moderate to advanced chronic periodontitis. Background Data: Laser applications in dental treatment are now more common in the literature. However, limited data are available on the potential effects of the low-power laser as an adjunct to non-surgical periodontal therapy for managing patients with moderate to advanced periodontal disease. Materials and Methods: Sixteen patients with probing pocket depth (PPD) ≥5 mm and comparable bone defects on both sides of the mouth were recruited. Supragingival plaque (PL), bleeding on probing (BOP), PPD, and probing attachment level (PAL) were recorded at baseline and at 3, 6, 9, and 12 mo, while gingival crevicular fluid (GCF) samples and standardized intra-oral radiographs for digital subtraction radiography were taken at baseline and at 1, 3, 6, 9, and 12 mo. After non-surgical mechanical periodontal treatment, the test sites were selected randomly and irradiated with a low-power He-Ne laser (output power 0.2 mW) for 10 min for a total of eight times in the first 3-mo period, while the control sites received no additional treatment. Results: PL percentage (83-16%) and BOP percentage (95-34%) decreased significantly after 12 mo. Statistically significant changes in reductions of PPD and GCF volume, gain in PAL, and increase in recession were seen in both test and control sites when compared to baseline (p < 0.05). No statistically significant differences in any clinical parameters or radiographic findings were found between the test and control sites. Changes in GCF volume were significant only at 3 mo in the test sites. Conclusion: Within the limits of this pilot study, the use of the low-power He-Ne laser as an adjunct to non-surgical periodontal therapy in patients with moderate to advanced chronic periodontitis did not seem to provide additional clinical benefit. © 2009 Mary Ann Liebert, Inc.published_or_final_versio

Partial nephrectomy for T1 renal cancer can achieve an equivalent oncological outcome to radical nephrectomy with better renal preservation: the way to go

INTRODUCTION: Patients who undergo partial nephrectomy have been shown to be at decreased risk of renal impairment compared with radical nephrectomy. We examined the oncological outcome of patients in our centre who underwent partial or radical nephrectomy for T1 renal cancer (7 cm or smaller), and compared the likelihood of developing chronic kidney disease. METHODS: This historical cohort study with internal comparison was conducted in a tertiary hospital in Hong Kong. A cohort of 86 patients with solitary T1 renal cancer and a normal contralateral kidney who underwent radical (38 patients) or partial (48 patients) nephrectomy between January 2005 and December 2010 was included. The overall and cancer-free survival, change in glomerular filtration rate, and new onset of chronic kidney disease were compared between the radical and partial nephrectomy groups. RESULTS: A total of 32 (84%) radical nephrectomy patients and 43 (90%) partial nephrectomy patients were alive by 31 December 2012. The mean follow-up was 43.5 (standard deviation, 22.4) months. There was no significant difference in overall survival (P=0.29) or cancer-free survival (P=0.29) between the two groups. Both groups enjoyed good oncological outcome with no recurrence in the partial nephrectomy group. Overall, 18 (21%) patients had pre-existing chronic kidney disease. The partial nephrectomy group had a significantly smaller median reduction in glomerular filtration rate (12.6% vs 35.4%; P<0.001), and radical nephrectomy carried a significantly higher risk of developing chronic kidney disease (hazard ratio=5.44; 95% confidence interval, 1.26-23.55; P=0.02). CONCLUSIONS: Compared with radical nephrectomy, partial nephrectomy can prevent chronic kidney disease and still achieve an excellent oncological outcome for T1 renal tumours, in particular T1a tumours and tumours with a low R.E.N.A.L. score.published_or_final_versio

The collaboration of quality mentorship network and university

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Toward a university-community-school partnership model - the experience of child development fund

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Radical versus partial nephrectomy for T1 renal cancer: equivalent oncological outcome with better renal preservation

OBJECTIVE: To examine and compare the outcome of radical and partial nephrectomy for T1 renal cancer (≤7 cm) in our centre. PATIENTS AND METHOD: Between January 2005 and December 2010, 38 (44.2%) radical nephrectomies (RN) and 48 (55.8%) partial nephrectomies (PN) were performed for solitary, T1 renal cancer in patients with normal contralateral kidney. GFR was estimated with the Modification of Diet in Renal Disease (MDRD) formula. CKD was defined as GFR lower than 60 mL/min per 1.73 m2. Cox regression model was used to compare overall survival and new onset of CKD. RESULTS: At last follow-up 32 RN patients (84.2%) and 43 PN patients (89.6%) were alive. There was no significant difference in overall survival between RN and PN patients (hazard ratio, 0.673; 95% confidence interval [CI], 0.128–3.529; p = 0.64). 1 RN patient (2.6%) developed systemic metastasis. RN patients had significantly higher reduction rate in GFR (35.4% vs 12.6%, p = 0.000), and higher risk in developing CKD (hazard ratio, 6.308; 95% CI, 2.074–19.189, p = 0.001). CONCLUSION: Relative to RN in managing T1 renal cancer, PN has equivalent survival and oncological clearance, with superiority in renal preservation and lower incidence of new CKD onset. PN should be the treatment of choice for T1 renal cancer.postprin

University’s collaboration with schools on adolescence development among disadvantaged youths

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Fuzzy control of the dual-stage feeding system consisting of a piezoelectric actuator and a linear motor for electrical discharge machining

Gap width is an important factor that affects material removal rate, surface finish, and machining stability in electrical discharge machining processes. This research is to develop a novel control method for a new hybrid positioning system which consists of a linear motor and a piezoelectric actuator for high-efficiency electrical discharge machining processes. In the new system, the linear motor provides the macro feeding while the piezoelectric actuator feeds the workpiece in micro scale at high frequency. To reduce the delay caused by separate movements of the linear motor and piezoelectric actuator, a new control algorithm was developed to synchronize the movements of the motor and piezoelectric actuator. A fuzzy control system was used to control the feeding process. Piezoelectric actuator position and its speed were selected as the fuzzy inputs, while the fuzzy output was the linear motor speed. Cutting experiments were conducted, and results show that the fuzzy system is more powerful than the conventional algorithm and the new algorithm with constant motor speed. An increase in material removal rate of 1.6 times was achieved using the proposed fuzzy control algorithm

Behavioral activation for dementia caregivers: scheduling pleasant events and enhancing communications

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How can the R.E.N.A.L. nephrometry scoring system aid management of a solid renal mass?

OBJECTIVES. To investigate use of the R.E.N.A.L. nephrometry score in relation to the choice of treatment and postoperative complications for renal masses. DESIGN. Case series. SETTING. A tertiary referral hospital in Hong Kong. PATIENTS. Data of patients undergoing nephrectomy were collected retrospectively from a clinical database and analysed. A R.E.N.A.L. nephrometry score was allocated to each renal tumour by a blinded qualified radiologist, utilising computerised imaging systems. Patient demographics, choice of surgery (radical vs partial), and approaches (open vs minimally invasive) were analysed with respect to their R.E.N.A.L. score. RESULTS. In all, 74 patients were included during the study period, of which 38 underwent partial nephrectomy and 36 underwent radical nephrectomy. No differences between the groups were found with respect to patient demographics. There were significant differences between the partial and radical nephrectomy groups in terms of their mean nephrometry score (6.9 vs 9.3, P<0.001). The mean nephrometry sum was also significantly different in the open approach versus the minimally invasive approach in patients having partial nephrectomy (7.8 vs 6.0, P=0.001). There was no difference in the postoperative 90-day morbidity and mortality in the partial nephrectomy and radical nephrectomy groups. CONCLUSIONS. The R.E.N.A.L. nephrometry score of a renal mass correlated significantly with our choice of surgery (partial vs radical) and our approach to surgery (open vs minimally invasive surgery), particularly in the partial nephrectomy group. It does not, however, correlate with postoperative complications. The nephrometry score provides a useful tool for objectively describing renal mass characteristics and enhancing better communication for the operative planning directed at renal masses.published_or_final_versio