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Conventional methods such as matched filtering, fractional lower order statistics cross ambiguity function, and recent methods such as compressed sensing and track-before-detect are used for target detection by passive radars. Target detection using these algorithms usually assumes that the background noise is Gaussian. However, non-Gaussian impulsive noise is inherent in real world radar problems. In this paper, a new optimization based algorithm that uses weighted l 1 and l 2 norms is proposed as an alternative to the existing algorithms whose performance degrades in the presence of impulsive noise. To determine the weights of these norms, the parameter that quantifies the impulsiveness level of the noise is estimated. In the proposed algorithm, the aim is to increase the target detection performance of a universal mobile telecommunication system (UMTS) based passive radars by facilitating higher resolution with better suppression of the sidelobes in both range and Doppler. The results obtained from both simulated data with α stable distribution, and real data recorded by a UMTS based passive radar platform are presented to demonstrate the superiority of the proposed algorithm. The results show that the proposed algorithm provides more robust and accurate detection performance for noise models with different impulsiveness levels compared to the conventional methods.

Background: Fibroblast growth factor (FGF)-23 is a recently discovered phosphaturic hormone that increases in chronic kidney disease (CKD). It has been accepted as a determinant of mortality and a therapeutic target in these patients. Ghrelin is a hormone that has roles in energy and nutrient metabolism. Ghrelin level was found to be increased in CKD patients. This is a controlled study in which the relationship between FGF-23 and ghrelin levels in CKD patients has been studied., Methods: Three groups were involved: 88 individuals. Dialysis group (DG, 33 patients) including patients on hemodialysis (21 patients) or peritoneal dialysis program (12 patients); predialysis group (PG, 29 patients) consisting of patients with stage-3 CKD; and the control group (CG, 29 individuals) of healthy adults. Serum FGF-23 and ghrelin levels were measured as well as routine biochemical parameters., Results: FGF-23 levels were similar within the groups (CG: 268±45 pg/mL, PG: 284±94 pg/mL, DG: 259±87 pg/mL, P=0.11). Ghrelin level was higher in the PG group compared with the DG and CG, while DG had higher ghrelin level than the CG (CG: 2.79±0.38 ng/mL, PG: 4.53±1.18 ng/mL, DG: 3.98±0.89 ng/mL). When all groups were studied together; a strong correlation was found between FGF-23 and ghrelin levels. When the analysis was repeated with PG and DG accepted as CKD group; this strong correlation persisted; while it was not true for the CG., Conclusions: There might be a strong correlation between FGF-23 and ghrelin levels irrespective of the stage of CKD and the dialysis modality. There is need for further studies to clarify the pathophysiological link between these parameters.

We aimed to compare the efficacy of intra-articular injections of a lower molecular weight hyaluronan (LMW HA) (Ostenil) with a higher molecular weight viscosupplement (hylan G-F 20, Synvisc) in hip osteoarthritis. For this purpose, 43 patients (56 hips) with hip osteoarthritis with a visual analogue scale (VAS) pain score higher than 50/100, a Lequesne index greater than 6, and persistence of the pain for longer than 3 months despite all conservative methods were enrolled in the study and randomly assigned to two groups: 25 (32 hips) received LMW HA and the remaining 18 patients (24 hips) received hylan G-F 20. Three injections were administered once weekly to each patient under fluoroscopic guidance. During the 6-month follow-up period, the primary outcomes were assessed at the 1st, 3rd, and 6th month by VAS, WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index), and Lequesne index. The intra-articular injections produced a significant reduction in VAS, WOMAC, and Lequesne index scores in both groups. After three injections, improvement was prominent at the 1st month and maintained for 6 months in both groups. The percentage reduction was 38 and 40% (p<0.001) in VAS pain score, 43 and 40% in WOMAC (p<0.001), and 47 and 49% in Lequesne index (p<0.001) in the LMW HA and hylan G-F groups at the 6th month, respectively. However, there were no significant differences in outcomes between any of the measurements at the 1st, 3rd, and 6th month between the two groups (p>0.05). No systemic adverse effect was recorded. Local adverse effects consisting of pain and/or swelling were noted in 3 of 32 hips (9%) injected with LMW HA and in 3 of 24 hips (12.5%) injected with hylan G-F 20. In conclusion, both types of viscosupplementation produced a significant clinical improvement during the 6-month follow-up period. However, no significant difference was found in outcomes between higher and lower molecular weight hyaluronan.