Autocatalysis as The Natural Philosophy Underlying Complexity and Biological Evolution

The importance and different aspects of autocatalysis in evolution was analyzed. The behaviour of autocatalytic reactions mainly the Lotka-Volterra and the Schlögl equations were discussed in terms of phase change, entropy, and their oscillation frequency. The increase of complexity as the general direction of evolution was examined on some patterns in terms of both their entropy and information content. In addition, the relation between stability and functionality, stability and cohesion were discussed. It was concluded that evolution drifts in the direction of increasing complexity as a kind of natural philosophy to counteract the increase of entropy in the universe.autocatalysis, entropy, evolution, complexity, information, oscillation frequency, cohesion

Evaluation of beta-blockers on left ventricular dyssynchrony and reverse remodeling in idiopathic dilated cardiomyopathy: A randomized trial of carvedilol and metoprolol

Background: The effect of b-blockage on cardiac dyssynchrony in idiopathic dilated cardio­myopathy (IDC) is unknown. This study evaluated the impact of carvedilol and metoprolol succinate on left ventricular (LV) dyssynchrony and reverse remodeling in IDC. Methods: In this small, prospective, double-blind study, we randomly assigned 81 IDC pa­tients to receive carvedilol or metoprolol succinate. Echocardiographic measurements (dyssyn­chrony, LV volumes and ejection fraction [EF]) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels were obtained at baseline and at first and sixth month of therapy. Results: A total of 74 (91%) patients completed all investigations at sixth month (38 and 36 taking carvedilol and metoprolol succinate, respectively). In the carvedilol group, reduction in LV end diastolic volume (D LVEDV at 6 months, 50 ± 15 mL to 40 ± 17 mL, p = 0.03) and increase in LVEF (D LVEF, 7 ± 2% to 5 ± 3%, p = 0.02) was higher compared to the meto­prolol group. Also improvement in inter-ventricular dyssynchrony achieved with carvedilol was higher than metoprolol (D interventricular delay at 6 months, 11 ± 8 ms to 6 ± 7 ms, p = 0.03). However, improvement in intraventricular dyssynchrony was similar in the two groups (D intraventricular delay, 9 ± 7 ms to 9 ± 6 ms, p = 0.91). Improvements in LV mechanical dyssynchrony and reverse remodeling achieved with both drugs were accompanied by reduction in NT-proBNP levels in both carvedilol and metoprolol groups (1614 ± 685 pg/mL to 654 ± ± 488 pg/mL and 1686 ± 730 pg/mL to 583 ± 396 pg/mL, respectively, p < 0.001 for both). Conclusions: Although reduction in LVEDV and increase in LVEF was higher with carvedilol, improvement in intraventricular dyssynchrony was similar in carvedilol and metoprolol groups.

Proactive Wireless Caching at Mobile User Devices for Energy Efficiency

Proactive content caching at user terminals is studied from an energy efficiency perspective. Assuming that the variable-rate demands of a user can be predicted accurately over a certain time period, the optimal transmission strategy that minimizes the total energy consumption is characterized. The reduction in the energy consumption is obtained both by increasing the total transmission time of a request, and by downloading it at better channel conditions, rather than downloading it at the time of use. Both gains are possible thanks to the limited cache memory at the user device, in which the pre-downloaded content is stored until it is requested by the application layer, such as a video player. We formulate the optimal proactive transmission strategy as the solution of a convex optimization problem, and evaluate the minimum total energy requirement numerically. We also provide a backward water-filling interpretation for the optimal caching strategy

Synthesis optimization and characterization of chitosan-coated iron oxide nanoparticles produced for biomedical applications

WOS: 000310608100037The chitosan-coated magnetic nanoparticles (CS MNPs) were in situ synthesized by cross-linking method. In this method; during the adsorption of cationic chitosan molecules onto the surface of anionic magnetic nanoparticles (MNPs) with electrostatic interactions, tripolyphosphate (TPP) is added for ionic cross-linking of the chitosan molecules with each other. The characterization of synthesized nanoparticles was performed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS/ESCA), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), thermal gravimetric analysis (TGA), and vibrating sample magnetometry (VSM) analyses. The XRD and XPS analyses proved that the synthesized iron oxide was magnetite (Fe3O4). The layer of chitosan on the magnetite surface was confirmed by FTIR. TEM results demonstrated a spherical morphology. In the synthesis, at higher NH4OH concentrations, smaller sized nanoparticles were obtained. The average diameters were generally between 2 and 8 nm for CS MNPs in TEM and between 58 and 103 nm in DLS. The average diameters of bare MNPs were found as around 18 nm both in TEM and DLS. TGA results indicated that the chitosan content of CS MNPs were between 15 and 23 % by weight. Bare and CS MNPs were superparamagnetic. These nanoparticles were found non-cytotoxic on cancer cell lines (SiHa, HeLa). The synthesized MNPs have many potential applications in biomedicine including targeted drug delivery, magnetic resonance imaging (MRI), and magnetic hyperthermia.[TUBITAK-TBAG(1001)/109T949]The support of Assist. Prof. Dr Bora Mavis for FTIR is gratefully acknowledged, as well as financial support by TUBITAK-TBAG(1001)/109T949

Excess epicardial fat mass misrepresented as cardiomegaly in dry-weight assessment of a dialysis patient

PubMed ID: 22098686Obesity is a major health problem that has entered the nephrology community and is challenging our conventional management strategies. In this case report, we present a morbidly obese dialysis patient whom dry-weight assessment was disturbed by excess epicardial fat mass due to obesity. This case suggests that problems related to obesity seem not to be limited to dealing with obesity-associated kidney injury, chronic kidney disease and mortality, but also other concepts in nephrology such that, as described, excess epicardial fat mass related to morbid obesity in this patient erroneously suggested a high cardiothoracic index, and misled patient management. Interpretation of chest X-ray in dry-weight assessment should take into account the patient's body weight especially in obese cases and alternative diagnostic methods for correct determination of fluid status are highly needed. © 2011 The Authors. Hemodialysis International © 2011 International Society for Hemodialysis

Model-coupled GRACE-based analysis of hydrological dynamics of drying Lake Urmia and its basin

Lake Urmia basin (LUB), in northwestern Iran, is under the influence of extreme degradation due to a number of natural and anthropogenic factors. The existence of the Lake is critical for the microclimate of the region as well as the quality of human life and wildlife, which necessitates an up-to-date and holistic analysis of its hydrological dynamics. In this premise, satellite-based terrestrial water storage (TWS) received from the Gravity Recovery and Climate Experiment (GRACE) mission was coupled with hydrometeorological modelling and assessment tools to analyse the hydrological status of the lake and its basin. As a new gap-filling approach, the Seasonal-Trend decomposition using Locally estimated scatterplot smoothing (LOESS) (STL) decomposition technique was proposed in this study to reconstruct the missing TWS data. Integrating satellite precipitation data with the Catchment Land Surface Model (CLSM) and WaterGAP model outputs, the hydrological status of the lake was investigated. The STL-based TWS turned out to concord well with the simulated TWS from the CLSM indicating the acceptable performance of the proposed technique. The findings revealed that the LUB had undergone an alarming hydrological situation from 2003 to 2021 with a total loss of (Formula presented.) and (Formula presented.) from its TWS and groundwater storage (GWS), respectively. The water level time series also indicated that the water level of the lake had diminished with an annual rate of (Formula presented.) corresponding to a total water level depletion of about (Formula presented.) during the 2003–2021 period. The GRACE-derived TWS and GWS also agreed well with the CLSM simulations. Assessment of the extreme events of the LUB suggested that the basin suffered from a severe dry event in 2008 resulting in the depletion of its water storage and water level. It was also found that from 2003 onward, a critical hydrological setting had dominated the LUB with a negative hydrological balance of (Formula presented.)

PAMAM dendrimer-coated iron oxide nanoparticles: synthesis and characterization of different generations

This study focuses on the synthesis and characterization of different generations (G(0)-G(7)) of polyamidoamine (PAMAM) dendrimer-coated magnetic nanoparticles (DcMNPs). In this study, superparamagnetic iron oxide nanoparticles were synthesized by co-precipitation method. The synthesized nanoparticles were modified with aminopropyltrimethoxysilane for dendrimer coating. Aminosilane-modified MNPs were coated with PAMAM dendrimer. The characterization of synthesized nanoparticles was performed by X-ray diffraction, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering, and vibrating sample magnetometry (VSM) analyses. TEM images demonstrated that the DcMNPs have monodisperse size distribution with an average particle diameter of 16 +/- 5 nm. DcMNPs were found to be superparamagnetic through VSM analysis. The synthesis, aminosilane modification, and dendrimer coating of iron oxide nanoparticles were validated by FTIR and XPS analyses. Cellular internalization of nanoparticles was studied by inverted light scattering microscopy, and cytotoxicity was determined by XTT analysis. Results demonstrated that the synthesized DcMNPs, with their functional groups, symmetry perfection, size distribution, improved magnetic properties, and nontoxic characteristics could be suitable nanocarriers for targeted cancer therapy upon loading with various anticancer agents

Synthesis, characterization and osteoblastic activity of polycaprolactone nanofibers coated with biomimetic calcium phosphate

Immersion of electrospun polycaprolactone (PCL) nanofiber mats in calcium phosphate solutions similar to simulated body fluid resulted in deposition of biomimetic calcium phosphate layer on the nanofibers and thus a highly bioactive novel scaffold has been developed for bone tissue engineering. Coatings with adequate integrity, favorable chemistry and morphology were achieved in less than 6 h of immersion. In the coating solutions, use of lower concentrations of phosphate sources with respect to the literature values (i.e., 3.62 vs. 10 mM) was substantiated by a thermodynamic modeling approach. Recipe concentration combinations that were away from the calculated dicalcium phosphate phase stability region resulted in micron-sized calcium phosphates with native nanostructures. While the nano/microstructure formed by the deposited calcium phosphate layer is controlled by increasing the solution pH to above 6.5 and increasing the duration of immersion experimentally, the nanostructure imposed by the dimensions of the fibers was controlled by the polymer concentration (12% w/v), applied voltage (25 kV) and capillary tip to collector distance (35 cm). The deposited coating increased quantitatively by extending the soak up to 6 h. On the other hand, the porosity values attained in the scaffolds were around 87% and the biomimetic coatings did not alter the nanofiber mat porosities negatively since the deposition continued along the fibers after the first 2 h. Upon confirming the non-toxic nature of the electrospun PCL nanofiber mats, the effects of different nano/microstructures formed were evaluated by the osteoblastic activity. The levels of both alkaline phosphatase activity and osteocalcin were found to be higher in the coated PCL nanofibers than in the uncoated PCL nanofibers, indicating that biomimetic calcium phosphate on PCL nanofibers supports osteoblastic differentiation. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved

Comparison of the fracture resistance of simulated immature permanent teeth using various canal filling materials and fiber posts

Background: The purpose of this study was to compare the fracture resistances of immature teeth treated with MTA along with root canal obturation methods using AH Plus, MetaSEAL, MTA Fillapex sealers + lateral compaction technique, and Unicore quartz fiber posts. Materials and methods: Fifty single-rooted maxillary anterior teeth were divided into five groups. The crowns were dissected and root canals were enlarged. #6 Peeso reamers were allowed to protrude 1 mm. beyond the apex to simulate immature teeth. The apical 45 mm of each tooth was filled using Angelus white MTA. The remaining portions of canals were obturated as follows: Group 1: No backfilling (control), Group 2: AH Plus + gutta-percha, lateral compaction, Group 3: MetaSEAL + gutta-percha, lateral compaction, Group 4: MTA Fillapex + gutta-percha, lateral compaction, Group 5: UniCore Fiber posts luted using PermaFlo DC. The specimens were embedded into self-curing acrylic poured into identical cylinders which were mounted on a jig providing a 45 degrees angle. A compressive load increasing at 1 mm min-1 was applied and the maximum load at which fracture occurred was recorded. Statistical analysis was performed using KruskalWallis and Dunns multiple tests. Results: The highest fracture resistance was obtained with Group 5 (Fiber posts) whereas Group 4 (MTA Fillapex) yielded the lowest values. The mean fracture resistance value of Group 2 (AH Plus) was significantly higher than Group 4 (MTA Fillapex) (P = 0.001). The mean fracture value of Group 5 (Fiber posts) was significantly higher than Group 2 (AH Plus), Group 3 (MetaSEAL), and Group 4 (MTA Fillapex) (P = 0.02, 0.004, and 0.0001, respectively). Conclusion: Within the limitations of this study, UniCore quartz fiber posts provided the highest resistance. This methodology may specifically be advantageous for teeth with arrest of development at early stages, as these teeth are more susceptible to fracture owing to their excessively weak dentinal walls

The effect of oral supplementation with a combination of beta-hydroxy-beta-methylbutyrate, arginine and glutamine on wound healing: a retrospective analysis of diabetic haemodialysis patients

WOS: 000315798600001PubMed ID: 23311725Background: Diabetes is an important reason for end-stage renal failure and diabetic foot wounds worsen the life qualities of these patients. Protein and amino acid support accelerates the wound healing. The purpose of this retrospective study is to examine the effect of beta-hydroxy-beta-methylbutyrate, arginine and glutamine (Abound (R)) supplementation on the wound healing. Methods: A total of 11 diabetic dialysis patients were included in this retrospective study aiming to evaluate the effect of the diet support with beta-hydroxy-beta-methylbutyrate, arginine and glutamine on wound healing in diabetic dialysis patients. Pre-treatment and post-treatment wound depth and wound appearance were scored in accordance with the "Bates-Jensen" wound assessment tool. The results of 4-week treatment with beta-hydroxy-beta-methylbutyrate, arginine and glutamine (Abound (R)) support were evaluated in terms of wound healing. Results: The mean age of patients was 66 (SD: 10, range: 51-81) and 9 (81.8%) of them were males. After the 4-week treatment, in accordance with the Bates-Jensen scoring, healing was observed on the wound depth score of 7(63.6%) patients and on wound appearance score of 8(72.7%) patients out of 11. While the wound depth score of 4(36.4%) cases and wound appearance score of 3(27.3%) cases remained the same, no deterioration was observed on any cases throughout the follow-up period. Conclusion: In conclusion, our findings revealed that Abound treatment makes a positive contribution to the wound healing in diabetic dialysis patients.Abbott Nutrition TurkeyWe thank to Cagla Isman, MD and Prof. Sule Oktay, MD, PhD. from KAPPA Consultancy Training Research Ltd, Istanbul who provided editorial support, and to Mehmet Berktas, MD, MICR from KAPPA Consultancy Training Research Ltd, Istanbul for statistical analysis, and these services were supported by an unconditional research grant from Abbott Nutrition Turkey. Abbott Nutrition Turkey was not involved in study design, in the collection, analysis, and interpretation of data; in the writing of the manuscript; and in the decision to submit the manuscript for publication