Probabilistic Support Vector Machine Localization in Wireless Sensor Networks

Reza Samadian,Seyed Majid Noorhosseini 한국전자통신연구원 2011 ETRI Journal Vol.33 No.6

Sensor networks play an important role in making the dream of ubiquitous computing a reality. With a variety of applications, sensor networks have the potential to influence everyone’s life in the near future. However, there are a number of issues in deployment and exploitation of these networks that must be dealt with for sensor network applications to realize such potential. Localization of the sensor nodes, which is the subject of this paper, is one of the basic problems that must be solved for sensor networks to be effectively used. This paper proposes a probabilistic support vector machine (SVM)-based method to gain a fairly accurate localization of sensor nodes. As opposed to many existing methods, our method assumes almost no extra equipment on the sensor nodes. Our experiments demonstrate that the probabilistic SVM method (PSVM) provides a significant improvement over existing localization methods, particularly in sparse networks and rough environments. In addition, a post processing step for PSVM, called attractive/repulsive potential field localization, is proposed, which provides even more improvement on the accuracy of the sensor node locations.

Effects of Two Different Hip-Knee-Ankle-Foot Orthoses on Postural Stability in Subjects with Spinal Cord Injury: A Pilot Study

Mohammad Samadian,Monireh Ahmadi Bani,Navid Golchin,Mohammad Ali Mardani,John S. Head,Mokhtar Arazpour 대한척추외과학회 2019 Asian Spine Journal Vol.13 No.1

Study Design: Pilot study. Purpose: Evaluation of two different hip-knee-ankle-foot orthoses (HKAFOs; medial linkage reciprocating gait orthosis [MLRGO] and isocentric reciprocating gait orthosis [IRGO]) using gait and postural stability analysis in four subjects with spinal cord injury (SCI). Overview of Literature: To the best of our knowledge, no study has evaluated postural stability in subjects with SCI when using MLRGO and IRGO. Methods: The relative efficacy of each orthosis was evaluated with relevant gait parameters, and an assessment of postural stability and sway during usage was made. Each analysis was conducted following an appropriate period of training and acclimatization. The gait parameters employed in the study were walking speed, cadence, and endurance; these were recorded and analyzed using current, validated methods. Postural stability was assessed using a verified force plate measurement system, and a modified Falls Efficacy Scale (mFES) was used for the measurement of postural sway and the perceived fear of falling. Results: Walking speed, cadence, and endurance increased with the use of both HKAFOs. When the two types of HKAFOs were compared, all the parameters showed a slight (but not significant) increase with the use of MLRGO compared with the use of IRGO. In contrast, there were slight but insignificant improvements in postural sway with the use of IRGO. However, although there were no significant differences between the two sets of mFES scores, there was a slightly reduced fear of falling with the use of MLRGO compared with the use of IRGO in the static standing position. Conclusions: It is noteworthy that meaningful interpretations of results can only be drawn if a larger sample is employed. This pilot study showed no significant data; however, the results indicate that the use of MLRGO is superior to that of IRGO in terms of potential improvement in the mobility and confidence levels of subjects with SCI.

Using Resveratrol and Epigallocatechin-3-Gallate to Improve Cryopreservation of Stallion Spermatozoa With Low Quality

Nouri, Houshang,Shojaeian, Kamal,Samadian, Farhad,Lee, Soojung,Kohram, Hamid,Lee, Jeong Ik Elsevier 2018 Journal of equine veterinary science Vol.70 No.-

<P><B>Abstract</B></P> <P>Reactive oxygen species levels in semen with low quality increased from 25% to about 40%. Resveratrol (Res) is a natural grape-derived phytoalexin, and epigallocatechin-3-gallate (EGCG) is the major polyphenol in green tea (<I>Camellia sinensis</I>); both molecules are known to have high levels of antioxidant activity. The aim of this study was to investigate the effects of this antioxidant's supplementation on cryopreservation of stallion semen with poor quality. Experiment 1: Experiment design to asses stallions semen quality (n = 3). Arabian stallions were managed for breeding with fresh, extended, or chilled semen during 2 years (in two breeding season) with a resulting per cycle pregnancy rate (103/41 estrus cycle/conception) of 39.80%. A total of 81 ejaculates were collected and evaluated in fresh condition (total and progressive motility, membrane integrity, acrosome defects, morphology, and abnormal DNA condensation). Evaluation of several ejaculates revealed that sperm production and semen quality mostly did not change during the breeding season, maintaining normal sperm production with poor quality. Experiment 2: 18 ejaculates, collected with Missouri model artificial vagina from Arabian stallion (n = 3). Extended semen was centrifuged at 600 × g for 10 minutes. To eliminate individual stallion variability, the resulting sperm pellets were pooled and divided in seven different treatments in a final concentration of 100 × 10<SUP>6</SUP> sperm/mL by using semiskimmed milk extender containing no supplements (control), and the following supplements with three different concentrations: Res 5, 10, and 20 μM (Res 1, Res 2, Res 3, respectively) and EGCG 25, 50, 100 μM (EGCG 1, EGCG 2, and EGCG 3, respectively). After thawing, all samples were maintained at 37°C for 10 minutes. Evaluation of motility, plasma membrane integrity, viability, mitochondria activity, DNA fragmentation, and lipid peroxidation was determined. For all semen parameters, the lower concentration of Res (5 μM) and EGCG (25 μM) did not show significant differences compared to control (<I>P</I> > .05). Relative to the control group, Res 2 had better (<I>P</I> < .05) postthaw total and progressive motility, yet the higher concentrations (Res 3) showed a negative effect on total motility. Percentage of membrane integrity, viability, and mitochondrial activity was significantly greater in Res 2 and EGCG 2 extenders in comparison with the control group, respectively (<I>P</I> < .05). Results showed that malondialdehyde concentration was lower in Res 2 and EGCG 2 groups. In conclusion, the present study showed that the antioxidant Res prevents DNA damages in our stallions. The addition of Res and EGCG before cryopreservation can ameliorate mitochondrial activity in stallions with low-quality semen. Although further studies are needed, the present work showed that Res and EGCG could be considered as cryopreservation procedures in stallions with low-quality sperm and possibly equine, to avoid or minimize DNA damages, and preserve sperm plasma membrane integrity and mitochondrial activity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The aim of this study was to investigate the effects of resveratrol (Res) and epigallocatechin-3-gallate (EGCG) supplementation on cryopreservation of stallion (n = 3) spermatozoa with poor quality. </LI> <LI> Five micromolar of Res and 50 μM EGCG in semiskimmed milk extender before cryopreservation can ameliorate total and progressive motility, percentage of membrane integrity, and viability in stallions with low quality. </LI> <LI> In conclusion, the present study showed that the 5 μM Res could prevent DNA damages in subfertile stallions. </LI> <LI> Although further studies are needed, the present work showed that Res and EGCG could be considered as cryopreservation procedures in stallions with low-quality sperm and possibly equine, to avoid or minimize DNA damag

Effect of parameters on roll dynamic response of an articulated vehicle carrying liquids

Shahram Azadi,Ali Jafari,Masoud Samadian 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.3

Directional response and roll stability characteristics of a partly filled tractor semi-trailer vehicle, with cylindrical tank, under differentparameters and conditions are investigated. The effective parameters and conditions in the stability of a tractor semi-trailer carrying liquidcan be considered as filled volume, kinematic viscosity of liquid cargo and vehicle steering input. The dynamic interaction of liquid cargowith the tractor semi-trailer vehicle is evaluated by integrating a dynamic slosh model of the partly filled tank with five-degrees-offreedomof a tractor semi-trailer tank model. The dynamic fluid slosh within the tank is modeled using three-dimensional Navier-Stokesequations, coupled with the volume-of-fluid equations and analyzed using FLUENT software. The coupled tank-vehicle model is subsequentlyanalyzed to determine the roll stability characteristics for different conditions and maneuvers. The results show effects of parametervariations on roll stability of the vehicle carrying liquid and also fluid's behavior in interaction with a vehicle's dynamics.

A promising wound dressing based on alginate hydrogels containing vitamin D3 cross‑linked by calcium carbonate/d‑glucono‑δ‑lactone

Arian Ehterami,Majid Salehi,Saeed Farzamfar,Hadi Samadian,Ahmad Vaez,Hamed Sahrapeyma,Sadegh Ghorbani 대한의용생체공학회 2020 Biomedical Engineering Letters (BMEL) Vol.10 No.2

In the present study, we fabricated vitamin D 3 -loaded alginate hydrogel and assessed its wound healing capability in the animalmodel. The various concentrations of vitamin D3 were added to the pre-dissolved sodium alginate in deionized water andcross-linked by calcium carbonate in combination with D -glucono-δ-lactone. The microstructure, swelling behavior, weightloss, hemo- and cytocompatibility of the fabricated hydrogels were evaluated. In the last stage, the therapeutic effi cacy ofthe prepared hydrogels was evaluated in the full-thickness dermal wound model. The scanning electron microscopy imagesshowed that the prepared hydrogel was highly porous with the porosity of 89.2 ± 12.5% and contained the interconnectedpores. Weight loss assessment showed that the prepared hydrogel is biodegradable with the weight loss percentage of about89% in 14 days. The results showed that the prepared hydrogels were hemo- and cytocompatible. The animal study resultsimplied that alginate hydrogel/3000 IU vitamin D 3 group exhibited the highest wound closure present which was statisticallysignifi cant than the control group ( p < 0.05). Moreover, the histological examinations revealed that hydrogel containing3000 IU vitamin D3 had the best performance and induced the highest re-epithelialization and granular tissue formation. Allin all, this study suggests that alginate hydrogels with 3000 IU vitamin D 3 can be exploited as a potential wound dressingin skin tissue engineering.

Effects of short-term atorvastatin use in patients with calcium stones: A randomized placebo-controlled clinical trial

Fatemeh Taheri,Maryam Taheri,Abbas Basiri,Alireza Khoshdel,Fariba Samadian,Sanaz Tavasoli 대한비뇨의학회 2019 Investigative and Clinical Urology Vol.60 No.6

Purpose: A few experimental and observational studies have reported that atorvastatin prevents calcium oxalate stone formation. Our study is the first to investigate the effect of atorvastatin on 24-hour urinary metabolites, urinary malondialdehyde (U-MDA) (an oxidative stress marker) and urinary neutrophil gelatinase-associated lipocalin (U-NGAL) (a renal tubular injury marker) in patients with calcium stones and hyperoxaluria. Materials and Methods: This randomized, double-blind, placebo-controlled, parallel-group clinical trial included 32 adults with recurrent calcium stone formation and hyperoxaluria. All participants received a 3-month course of either atorvastatin (20 mg/d) or placebo of an identical shape. Both groups received the usual nutritional care based on the European Association of Urology guidelines. Results: Twenty-eight participants completed the study. Serum levels of total and low-density lipoprotein cholesterol decreased in the atorvastatin group, and these changes were significantly different between groups (p<0.001). No statistically significant differences were observed between intergroup changes of the 24-hour urinary metabolite analysis, the U-MDA to creatinine ratio and the U-NGAL to creatinine ratio. Conclusions: Atorvastatin administration at a dose of 20 mg/d for 3 months did not affect 24-hour urinary metabolite, U-MDA and U-NGAL levels in recurrent calcium stone formers. However, this study could not disprove the preventive role of atorvastatin in kidney stone formation. Future studies should consider a larger sample size, longer follow-up, different drug doses, and measurements of multiple biomarkers of oxidative stress and tubular injury.

Electrically Conductive Nanofibers Composed of Chitosan-grafted Polythiophene and Poly(ε-caprolactone) as Tissue Engineering Scaffold

Bakhshali Massoumi,Mojtaba Abbasian,Balal Khalilzadeh,Rana Jahanban-Esfahlan,Hadi Samadian,Hossein Derakhshankhah,Mehdi Jaymand 한국섬유공학회 2021 Fibers and polymers Vol.22 No.1

Two novel electrically conductive nanofibrous scaffolds based on chitosan-grafted polythiophene (CS-g-PTh),and chitosan-grafted polythiophene/poly(ε-caprolactone) (CS-g-PTh/PCL) have been fabricated through electrospinningtechnique, and their performances in tissue engineering (TE) application were preliminary investigated in terms of biological(biocompatibility, biodegradability, and enhancing the cells adhesion and proliferation) as well as physicochemical (composition,electroactivity, conductivity, hydrophilicity, and morphology) features. The conductivities of the CS-g-PTh and CS-g-PTh/PCL nanofibrous scaffolds were determined as 0.09 and 8×10-3 Scm-1, respectively. The developed CS-g-PTh/PCL scaffoldexhibited slightly higher cells proliferation (8.24±0.49) than those of the CS-g-PTh scaffold (7.1±0.38) in time period of 7days. The biodegradability tests using gravimetric approach revealed that the mass loss of CS-g-PTh and CS-g-PTh/PCLelectrospun nanofibers were about 28.1 and 37.3 wt.%, respectively, at the end of experiments (sixth weeks). It was foundthat the electrospinning of CS-g-PTh with PCL improves the nanofibers uniformity as well as the biological features (e.g.,biocompatibility and cell proliferation) of the resultant scaffold.