Derya Burcu Hazer

Complications of endoscopic surgery of the pituitary adenomas: analysis of 570 patients and review of the literature

Endoscopic transsphenoidal surgery is emerging as a minimally invasive and maximally effective procedure for pituitary adenomas. In this report we analyzed the complications in 624 procedures of endonasal transsphenoidal endoscopic surgery in the treatment of 570 patients with pituitary adenomas. The leading author (MB) operated pituitary adenomas via pure endoscopic endonasal transsphenoidal surgery between January 2006 and August 2011 at the Hacettepe University, Department of Neurosurgery in Ankara. Complications were assessed in 624 surgical procedures under five groups; rhinological, CSF leaks, infection, vascular and endocrinologic complications. We observed a total of 76 complications (12.1%). Rhinological complications occurred in 8 patients (1.3%): 4 epistaxis (0.6%) and 4 hyposmia (0.6%). Postoperative CSF leaks occurred in 8 patients (1.3%), and infectious complications occurred in 8 patients: 3 cases of sphenoidal sinusitis (0.4%), 5 cases of meningitis (0.8%). Only 1 case of internal carotid aneurysm rupture during the opening of sellar floor (0.16%) was observed. Endocrinologic complications occurred in 51 (8.1%) patients: Anterior pituitary deficiency in 12 (1.9%), transient diabetes insipidus (DI) in 29 (4.6%), permanent DI in 3 (0.4%) and inappropriate antidiuretic hormone secretion syndrome occurred in 7 (1.1%). There was no mortality directly related to the surgical procedure. The complication rates observed in our study suggests that the endoscopic pituitary surgery is at least as safe as microscopic transphenoidal surgery. These rates were obtained with due experience and well-coordinated teamwork. To further improve these rates, new technological developments will be helpful.

Treatment of acromegaly by endoscopic transsphenoidal surgery: surgical experience in 214 cases and cure rates according to current consensus criteria

OBJECT Acromegaly is a disease that has significant morbidity and mortality related to high levels of growth hormone (GH) and insulin-like growth factor-I (IGF-I), and is usually caused by pituitary adenomas. The goal in this study was to investigate the role of endoscopic transsphenoidal surgery and surgical experience in the treatment of GH adenoma cases in relation to surgical results and hormonal cure rates, and to perform a review of the literature. METHODS The authors present a retrospective analysis of 214 GH adenoma cases. Restoration of IGF-I levels to normal for age and sex, suppression of GH levels below 0.4 μg/L on the oral glucose tolerance test, and demonstration of the total removal of the tumor on MRI studies obtained after administration of contrast material at the 3-month postoperative follow-up visit were the criteria for cure. RESULTS In total 214 patients with a mean age of 41.9 ± 12 years (range 17-75 years) and a male/female ratio of 106/108 were enrolled in the study. Cure was achieved in 134 (62.6%) of 214 patients. One hundred sixty-nine patients were primary cases, and of these 109 (64.5%) were cured, whereas 61 patients were previously operated cases and of these 25 (41%) were cured. With a 51.1% decrease in the 1st month postoperatively, IGF-I levels were found to be predictive of cure (74.4% sensitivity and 73.7% specificity). Cut-off values for GH levels in predicting cure for the 1st day, 1st week, and 1st month postoperatively were 2.33, 2.05, and 2.25 μg/L, respectively. The cut-off value for surgical experience was 57 for primary surgeries (58.5% cure rate before this cut-off value compared with 72.6% after it; p = 0.025) and 108 for all operations (45.8% vs. 79.4%, p = 0.037). Although 28 patients were found to be in remission according to the criteria in 2000, they were not in remission according to the new consensus criteria. Nine of these cases (32.1%) had random GH levels < 1 μg/L at the 1-year follow-up. The 1-year IGF-I and GH levels in these 28 patients showed no significant difference when compared with the cases defined as cured according to the current criteria. CONCLUSIONS In acromegaly treatment, transsphenoidal endoscopic surgery performed by an expert senior surgeon and increased surgical experience are important for higher cure rates. Random GH levels < 2.33 μg/L after the 1st day postoperatively and a > 50% decrease in IGF-I levels after the 1st month postoperatively are predictive of cure. Moreover, there is no urgency for additional therapy in patients with GH levels of 0.4-1 μg/L and MRI sequences showing no tumor at the 3-month follow-up, because for these cases remission can be achieved at the 1-year follow-up.

Synthesis of microbial elastomers based on soybean oily acids. Biocompatibility studies

Biocompatibility studies of the autoxidized and unoxidized unsaturated medium-long chain length (m-lcl) co-poly-3-hydroxyalkanoates (m-lclPHAs) derived from soya oily acids have been reported. Pseudomonas oleovorans was grown on a series of mixtures of octanoic acid (OA) and soya oily acids (Sy) with weight ratios of 20:80, 28:72 and 50:50 in order to obtain unsaturated m-lcl copolyesters coded PHO-Sy-2080, PHO-Sy-2872 and PHO-Sy-5050, respectively. The PHA films were obtained by solvent cast from CHCl(3). They were all originally sticky and waxy except PHO-Sy-5050. Autoxidation of the unsaturated copolyester films was carried out on exposure to air at room temperature in order to obtain crosslinked polymers. They became a highly flexible elastomer after being autoxidized (about 40 days of autoxidation). The in vivo tissue reactions of the autoxidized PHAs were evaluated by subcutaneous implantation in rats. The rats appeared to be healthy throughout the implantation period. No symptom such as necrosis, abscess or tumorigenesis was observed in the vicinity of the implants. Retrieved materials varied in their physical appearance after 6 weeks of implantation. In vivo biocompatibility studies of the medical applications indicated that the microbial copolyesters obtained were all biocompatible and especially the PHOSy series of copolyesters had the highest biocompatibility among them.

Soft tissue response to the presence of polypropylene-G-poly(ethylene glycol) comb-type graft copolymers containing gold nanoparticles.

The aim of this study is to evaluate the soft tissue response of the pure and Au-embedded PPg-PEG. PP-g-PEG2000, PP-g-PEG4000, Au-PP-g-PEG2000, and AuPP-g-PEG4000 were obtained via chlorination of polypropylene and polyethylene glycol in the presence of a base with a “grafting onto” technique. Solvent cast films of these four copolymers with PP as a control group were embedded into five different rats. After 30 days of implantation, microscopic evaluation of inflammation and SEM analysis were done. PP had the most intense inflammatory reaction among the other polymers. PP-PEG block copolymers with high molecular weight and gold-nanoparticles-embedded ones revealed mild inflammatory reaction independently. SEM assessment revealed punched hole-like defects on the surface of all polymer samples except for PP. Graft copolymers with PEG, especially Au-attached ones, have favorable soft tissue response, and inflammatory reaction becomes milder as the number of PEG side chains increases.

Management of cerebrospinal fluid leak during endoscopic pituitary surgery.

OBJECTIVE Dural opening and closures are major steps in endoscopic pituitary surgery. Restoring the normal anatomy at the end of the procedure creates a natural barrier between the intrasellar compartment and the sinonasal cavity. METHODS In this study, we present a relatively simple dural opening and closure technique for endoscopic pituitary surgery. This technique provides a better alternative to the use of a more complex nasoseptal flap or the multilevel closure with artificial materials as it restores the normal anatomy after the tumor removal and provides a better physiological barrier between the sinonasal cavity and the intrasellar compartment. Incision is performed in circular or horseshoe fashion leaving a small peduncle, and then the dura is reflected. RESULTS Of the 733 endoscopic transsphenoidal procedures in 667 patients conducted between January 2006 and May 2012, we used this described technique in 50 cases (7.4%). In these 50 cases with dural flap, there was no postoperative CSF leakage. Intraoperative CSF leakage was observed in 135 (20.2%) of the 667 patients. In 15 (11.1%) of these 135 patients we used the dural flap technique accompanied with fat and/or fascia lata support. There was no postoperative leakage in these patients. In the remaining 120 (89.9%) patients who had intraoperative CSF leakage, we used fat and/or fascia lata for the reconstruction of the sella floor. But we observed postoperative CSF leakage in 12 (10%) of the 120 patients without the dural flap which were reoperated. CONCLUSION The dural flap technique we employ has several advantages. First of all, it allows optimal physiological reconstruction after the surgery. Secondly, the bridge between the flap and the main dura helps maintain the vascular supply, which in turn can radically shorten the healing time. Thirdly, this technique is obviously a better alternative to the time consuming and expensive multilevel closures with tissue sealants and artificial grafts.

Effects of pravastatin on cellular ultrastructure and hemorheology in rats after traumatic head injury

Pravastatin has neuroprotective effects against aging but its role in brain injury remains unclear. This study evaluated the effects of pravastatin on the ultrastructural changes and hemorheological parameters in rats after traumatic brain injury (TBI) of right parietal cortical contusion by a controlled weight-dropping method. There were three groups: (I) Sham operated group; (II) TBI + vehicle (saline) group; and (III) TBI + pravastatin group. Right parietal craniectomy was performed in all groups. In TBI + pravastatin group, pravastatin was administered orally at a dose of 1 mg/kg every day for 7 days starting at 24 hours after the injury. Plasma viscosity, erythrocyte deformability and erythrocyte aggregation were measured from blood samples of all rats on 2nd, 7th and 15th days. At the same time electron microscopic study was done on designated days for groups II and III. Treatment with pravastatin markedly increased aggregation amplitude and γIsc max values and significantly decreased erythrocyte deformability but did not change plasma viscosity in 2 weeks time. Ultrastructural parameters such as perinuclear edema, mitochondrial swelling and intraneuronal vacuoles were detected in lower degree in the statin group when compared to the saline group, especially decreased demyelinization and endothelial detachment was prominent. As a result, the hyperviscosity state with increased erythrocyte aggregation and decreased erythrocyte deformability induced by pravastatin in this study was accompanied by an improvement of the ultrastructural findings in TBI. This hyperviscosity state may be a compensatory mechanism to increase the oxygenation of the injured tissue by inducing the release of antiaggregant and vasodilatory substances by increasing shear stress. Therefore, we suggest that prolonged pravastatin usage may exert affirmative effects on traumatic brain injury conditions by increasing blood viscosity.

Medical applications of amphiphilic comb type graft copolymer containing inorganic nanoparticles

P nanofibers have great scientific and technological interest because of their wide-range of applications in biomedicine and biotechnology. The electrospinning technique has been realized as an efficient technology, among a few others, to create polymer nanofibers in the form of nonwoven mats from laboratory to industrial scale. Extracelluar matrix (ECM) of tissue is composed of a variety of proteins and polysaccharides that are secreted locally and assembled into nano structured fibrous networks in close association with the surface of the cell that produced them. The electrospinning process enables the production of nanometer-sized fibers with porosity matching that of natural ECM, and thus offers significant advantages for tissue scaffolding applications in biomedical engineering. Mats made of the nanofibers also find other exciting applications in wound dressing materials, drug delivery, sensing pathogens, filtering toxic products and engineering complex tissues. In our research we developed verities of electrospun nanofibers of polymers for wide range of biomedical applications because of their versatile nature in surface functionalizaiton and encapsulation capability, biodegradation, and biocompatibility. Polymer composite nanofibers obtained from mixtures of synthetic and natural polymers can behave cooperatively to demonstrate unique combinations of mechanical, controllable bioresorption rate and structural properties. This flexibility allows nanofibers in the engineering of specific tissues with desirable release rates of biomolecules. We have also developed a unique technique to design a functional nanofiber membrane whose primary components are synthetic as well as naturally derived biopolymers and, ceramic and metal particles.C materials are gaining interest due to their potential applications as nanoporous materials. In addition, interest in metastable solids is rising exponentially as well. The vast amount of possible structures with different properties would lead to new materials with a wide range of applications. In this work we will focus, concretely, on the cluster-assembled structures of II-VI materials, due to their semiconducting properties. The existence of inorganic hollow ZnS and CdS fullerene like clusters was theoretically predicted and then experimentally confirmed recently. These clusters have been predicted to have different metastable cluster-assembled structures, namely, those of FAU, LTA and SOD zeolite-like structures. In addition, the hollow nature of these structures allow for the design of endohedrally-doped building blocks, which would change the properties of the materials according to the dopant material. Concretely, these clusters were seen to trap alkali metals and halogens, being the ionization energies (IE) of the formers very similar to the electron affinities (EA) of the latter. Concretely, we have focused on the assembling of bare M12S12 and endohedral X@M12S12-Y@M12S12 dimers, being M Zn or Cd, X an alkali metal (Na or K) and X a halogen (Cl or Br). In all cases the structures were fully optimized, and their thermal stability was confirmed by ab initio thermal molecular dynamics calculations. Due to their nanoporous structure, these zeolite shaped solids could be used in heterogeneous catalysis, as storage materials and molecular sieves. Jon M. Matxain, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010Certain cationic phenylene ethynylene (CPE)-based polymers (PPEs) and oligomers (OPEs) exhibit darkand light-activated antimicrobial activity. Until recently, it was unknown if they would also exhibit similar biocidal activity toward mammalian cells. Based on their biocidal activity and diversity of repeat unit number and functional groups, a variety of CPEs, PPEs, and OPEs were selected for these studies, and were examined for their toxicity toward mammalian cells at three levels: cytoxicity testing of cell monolayers, skin irritation testing of tissues, and intracellular co-localization. As expected, concentration plays the largest role in determining viability. The lack of skin irritation for all substances alleviates initial safety concerns for products based on these CPEs and OPEs. In all cases, the addition of light changed the effects of the compounds on the mammalian cells. The modes of action of these compounds appear to be governed primarily by length.T science and technology of nanomaterials is the major turning point in the industrial development of the twenty-first century. Most industrial sectors and biosciences have benefitted greatly from manipulation of materials at the nanometer scale. Nanotechnology has benefitted the field of corrosion prevention to a considerable level and much advancement is expected in the near future. A number of research investigations have been done in this direction on various aspects such as electrochemical corrosion or high temperature oxidation resistance of nanostructured materials, application of nanomaterials in enhancing the barrier properties of advanced surface coatings and nanotechnology associated smart coatings. The presentation covers different roles of nanomaterials in the corrosion control scenario and the methods to enhance the corrosion resistance of nanostructured materials. Advanced nanotechnology associated surface coating strategies will be highlighted. Viswanathan S. Saji, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010U protein-surface interaction and protein adsorption properties of polymer surfaces are of crucial importance for the use of polymers in biomedical implants. Though polymer surfaces do not provide any receptors for cellular proteins, soluble proteins can bind to these polymer surfaces and in turn act as receptors for cellular proteins. In the process, depending on the surface properties of the polymer, the bound proteins can assume unrecognizable conformations allowing cellular proteins to identify them as foreign bodies and trigger attacks as a cellular response. These infighting posses a major challenge in biomedical engineering. An appropriate understanding of the adsorption free energy and the conformational changes of proteins upon their interaction with synthetic surfaces is critical in the development of biomaterials suitable for implants because those changes determine cellular responses to implanted materials and substrates. The classical molecular dynamic (MD) simulation is one of the direct methods which can, in principle, provide a detail analysis of the molecular behavior of the protein-surface interaction. However, there are challenges from the compatibility of the force-field parameters that needs to be overcome. MD force-field parameters developed for liquid phase proteins and solid phase surfaces serve well for the respective phases but the interphase interaction between a surface and a protein or water appear to be inappropriate and the scale of inadequacy vary significantly based on the hydrophobicity of the surface. To circumvent this situation, we developed a dualFF formalism in CHARMM, where dedicated parameter sets are being used for the solid phase surface and the liquid phase protein and water but to describe the interphase interaction between protein-surface and water-surface a third set of parameters are used which are tuned to respond to the polarization effect on the liquid phase protein and the water in the presence of the solid phase surface. Simulation results for peptide adsorption on self-assembled monolayer surfaces with hydrophobic and hydrophilic functionalized groups will be presented with untuned and tuned interphase force-filed parameters and compared with experimental data. Results demonstrate the suitability of the dualFF method to characterize protein-surface interaction and designing appropriate functionalized surface for biomedical implants. P. K. Biswas, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010Numerical simulations of transport of atmospheric aerosols and nanoparticles in models of various parts of human respiratory system are performed using the Navier-Stokes equations in continuum regime and slip/transitional flow regime. Although the primary interest of this investigation is the study and understanding of aerosol transport in human respiratory system, the computational modeling and analysis of the entire system is currently not feasible because of extreme complexity of airflow in the nasal cavities, oral and bronchial airways of the respiratory system. Because of geometric complexity of pathways, the flow field features include turbulent jet-like flow, recirculating flow, secondary flow (Dean’s flow), vortical flows, large pressure drops etc. Such complex flows generated in nasal cavities and oral airways eventually propagate into the tracheobronchial airways. In order to make the problem tractable, simple rigid models of nasal cavities, oral and bronchial airways are considered; fluid/structure interactions are neglected. CFD modeling results show that essential features of the flow fields in these passages can be captured; however the proper formulation and implementation of boundary conditions is critical in obtaining accurate solutions. We assume that aerosols are spherical, non-interacting and mono-disperse, and deposit upon contact with the airway surface. These dilute particle suspensions are modeled with the Euler-Lagrange approach for micron size particles and in the Euler-Euler framework for nanoparticles. The results show that micron size particles deposit non-uniformly with high concentrations while the nanoparticles almost coat the airway surfaces. Although preliminary, these simulation studies have implications in assessing the detrimental health effects in the case of inhaled toxic nanoparticles. The variations in several parameters employed in the models such as the geometric features (which can be individual-specific), the inhaling/exhaling patterns, particle distributions (from micron to nanoscale), boundary conditions etc. can significantly affect the particle deposition in the respiratory system pathways.T presentation will highlight recent advances in nanostructured ceramic/polymer composites for controlled drug delivery and enhanced human mesenchymal stem cell (hMSC) functions for regenerative medicine applications. Specifically, we designed and fabricated nanophase ceramic/polymer composites into 2D and 3D structures at the nanoand micro-scale to mimic properties of natural bone closely. Results showed that osteoblast (bone-forming cell) functions increased the most by the nanocomposites with the closest nano-surface characteristics to bone. We further investigated the loading of a bone morphogenetic protein (BMP-7)-derived short peptide (DIF-7c) into the nanocomposites and studied the prolonged release of the peptide and their potential for osteogenic differentiation of hMSCs. Results showed that the nanocomposites promoted hMSC adhesion than the polymer controls and enhanced osteogenic differentiation (i.e. calcium deposition and alkaline phosphatase activity) of hMSCs in vitro. In summary, the nanocomposites are promising for more effective bone tissue regeneration and should be further studied for clinical translation. Huinan Liu, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010The interest has been attracted since 1998 for InP quantum dot (QD) lasers grown on GaAs substrates [M. K. Zundel et al., Appl. Phys. Lett., 73, (1998)], [J. Porsche et al., IEEE J. Sel. Top. Quantum Electron., 6, (2000)], [G. Walter et al., Appl. Phys. Lett., 79, (2001)]. Self-assembled InP QD lasers grown on GaAs substrates emitting wavelength range between 650780nm have potential applications in photodynamic therapies, dual wavelength sources and biophotonic sensing. As a different material from the more-studied InAs on GaAs system, they also offer the possibility of a more generic understanding of QD laser physics. Here we focus on the temperature dependence of the threshold current density (Jth) observing distinctive behaviour that has also been observed in p-doped InAs QD laser devices. Threshold current density (Jth) as a function of temperature for 2000μm long devices at 750 0 C growth temperature exhibits a distinctive dependence on the operating temperature, where from 190K it initially increases with temperature until it reaches a local maximum at 220K, then it decreases with increasing temperature until a minimum is reached at 260K. Above 260K Jth increases superlinearly with temperature. This type of behaviour has previously been observed for p-doped InAs/GaAs quantum dot lasers at lower temperatures [I. C. Sandall et al., Appl. Phys. Lett., 88, (2006)]. The measured unamplified spontaneous emission shows two peaks corresponding to emission from QD and QW states and this is used to explain the behaviour of Jth with temperature in terms of the carrier distributions in the QD and QW states without the need for Auger recombination.D mining of iron ore, huge amount of fines is being generated which needs to be pelletized to use them in blast furnace for iron making process. Pellet quality plays a vital role in decreasing coke rate and increasing the blast furnace productivity. Indian iron ores are suffering from high amount of alumina, which is a deleterious constituent in both pelletizing as well as iron making process. Flux used plays a crucial part in determining pellet quality. Silicate fluxes like pyroxenite and olivine shows improvement in high temperature metallurgical properties but still could not met the desired quality due its improper assimilation, and high content of alumina in iron ore. Carbonate fluxes like limestone or dolomite is more often used in pelletization for alternative iron making processes. Thermodynamic modeling and experiments helped in the evolution of the new tailor-made combination of carbonate and silicate minerals which together provides an attractive solution to achieve sustainable pelletizing with desired quality pellets, and substantiated by their microstructures. During firing, the carbonate mineral dissociates and reacts with high alumina iron ore to form liquid bonding phase in the pellet improving its strength at room and low temperatures up to 600oC (i.e., CCS and RDI), while the silicate mineral forms high melting point phase which keeps the pellet quality intact even at high temperatures beyond 1000oC (i.e., Softening temperature). These superior quality pellets improves the productivity by 12%, mitigate the pellet fines generation by 35%, and decreases the blast furnace coke rate, hence low CO2 emissions. T. K. Sandeep Kumar, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010A transmission electron microscopy (TEM)/ scanning transmission electron microscopy (STEM) and in-situ TEM have emerged as powerful tools for the characterization of energy materials. Aberration-corrected TEM/STEM enables atomic and structural imaging resolution below 0.1 nanometers while performing chemical analysis at the atomic level. In-situ TEM allows dynamic real-time imaging of energy materials behavior. In this talk, a brief overview of aberration-corrected TEM/STEM and in-situ TEM will be presented and related to the quest for investigating energy materials. Subsequently, the power of these techniques in providing scientific insight into developing Li-ion batteries, proton exchange membrane fuel cells and catalyst nanoparticles will be discussed. Paulo J. Ferreira, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010Supercapacitors with high power density in combination with batteries with high energy density can lead to efficient energy storage systems. Recent studies from NREL have shown that HEVs equipped with 40-100 Wh/kg supercapacitors could improve the fuel efficiency by 15-30%. However, energy density of state-of-the-art capacitors (2-20 Wh/kg) is an order of magnitude lower than metal hydride (40-100 Wh/kg) and Li-ion batteries (120-170 Wh/kg). The key scientific barrier for low capacitances is the presence of micropores on the active surface of electrodes that are not accessible to electrolytes. Although there are a few exceptions, it has been widely accepted that high surface area materials with pores substantially larger than the size of solvated ions in the electrolyte is a prerequisite for achieving high capacitances. Research efforts are focused on increasing active surface area, pore size control and increasing operational voltage by use of ionic liquid electrolytes. Hybrid carbon based materials with enhanced electrolyte accessibility could serve as potential alternatives which requires precise control of pore sizes and presents a grand challenge. We will present our results on controlled synthesis and electrochemical studies of hierarchical nanoporous carbon architectures derived “metal organic frameworks (MOFs)”. MOFs represent a new class of materials with well-defined porosity, structure tailorability and tunable functionality with considerable attention due to their promise in wide range of applications. Porous carbons derived from MOFs (CMOFs) exhibited high surface area, porosity and pore volume. To further improve the overall electrical conductivity of CMOFs, heteroatoms such as nitrogen can be introduced using amine linkers during MOF synthesis. The Brunauer-Emmett-Teller (BET) surface areas of the as-synthesized CMOFs are in the range 150-800 m2/g. Detailed synthesis strategies, effect of annealing temperature on the CMOFs structure and their electrochemical performances [Figure 1] as materials for supercapacitors will be discussed. Figure 1: Cyclic voltammetry curves: (a) CMOFs annealed at 700 and 900 oC showing enhanced capacitance with annealing temperature increase. (b) 100 cycle data for CMOFs showing good cycling stability.The present studies are implemented to recover valuable metals such as vanadium and tungsten from spent SCR catalysts for de-NOx.Optimized the experimental parameters by following order: soda roasting, at high temperature followed by water leaching. Then generated water leach liquor processed by hydrometallurgical routes namely precipitation and solvent extraction. In soda roasting process, sodium carbonate added 5 equivalent ratio at roasted temperature 850°C with 120min roasted time for 54μm average particle size of spent catalysts. After soda roasting process moved to water leaching for roasted spent catalysts. Before leaching process the roasted spent catalysts were grinded up to -45μm particle size. The leaching time is 30min at 40°C temperature, 10% pulp density. The final leaching efficiency obtained 46% of vanadium and 92% of tungsten by present process. Precipitation experiment carryout using MgCl2 as reagent to selectively precipitate vanadium component from water leach liquor containing vanadium and tungsten. Tungsten component showed large loss because of co-precipitation when precipitating vanadium component. Biography Dr. Jin-Young Lee has completed his PhD. from Kwangwoon University. He is the principal researcher of KIGAM. He has published more than 40 papers in reputed journals and has been serving as an editorial board member of KIRR(Korea Institute of Resources Recycling).Introduction There continues to be a need to develop sustainable and efficient technologies for the conversion of lignocellulosic biomass to hydrocarbon fuels and chemicals. The use of biomass for these purposes becomes increasingly important as the nation strives to reduce its reliance on limited and foreign petroleum resources, and minimizes its carbon footprint, while maintaining America’s technological competitiveness and creating green jobs.Multivalent battery systems like rechargeable magnesium (Mg) batteries are garnering more interest as candidate post-lithium (Li) battery systems, for eventual applications in electric vehicles (EVs) and plug-in hybrid vehicles (PHVs). This is primarily due to concerns over the long range performance of current Li battery systems, and the space requirements for future EVs and PHVs. Mg, being divalent and denser, is theoretically capable of delivering a higher volumetric energy-density (3833 mAh cm -3 ) than Li (2061 mAh cm -3 ), making it a viable alternative battery system for addressing such concerns. In order to be competitive with current Li-ion systems, high voltage and high capacity Mg systems must be developed. To date, various organohaloaluminates have been utilized as alternative electrolytes for Mg systems, due to the incompatibility of high voltage conventional battery electrolytes (TFSI, ClO4 , PF6 ) with Mg metal anodes. However, reports have shown that these organohaloaluminate electrolytes provide a limited operating voltage window when tested against typical battery current collectors. It has recently been reported that it is possible to use conventional battery electrolytes by changing the type of anode, from a Mg metal anode to a Mg-ion insertion-type anode (e.g. high energy-density Bi and Sn), enabling Mg-ion transport through the anode/electrolyte interface. Here, we report recent advancements in the use of such insertion-type anodes for rechargeable Mg-ion batteries, using conventional battery electrolytes, as well as advancements on cathode materials for Mg battery systems. Further, various issues at the electrode/electrolyte interfaces will be discussed via an overview of current Mg battery systems.In some applications of graphene, for example as electrode materials of supercapacitors and biomaterials supports, it is desirable that graphene is hydrophilic since hydrophilic graphene can improve the interaction between graphene and polar electrolytes or biological molecules. However, pristine graphene is strongly hydrophobic due to the inert nature. Therefore, the development of stable hydrophilic graphene surface is essential for the above applications. In this talk, it presents two different methods to realize this transition based on density functional calculations. It is found that applying external electric field or doping Al atoms into graphene can facilitate the H2O molecules dissociative adsorption on graphene, thus the presence of OH group on graphene converts graphene to be hydrophilic.Single layer graphene exhibits a theoretical specific surface area as high as 2630 m g and has an intrinsic capacitance around 21 μF cm -2 , making it excellent candidate for electrochemical capacitor applications. However, a major challenge in the field of energy storage devices by adopting graphene as electrode materials still remains to achieve highly porous structures with good quality in large scale production, because single layer graphene must be collected into various assemblies, in which the restacking due to the strong sheet-sheet van der Waals interactions is unavoidable. Thermal-related exfoliation production of graphene has been believed to be a promising strategy for practical applications, but the needed high temperature and special experimental environment hinder this method from wide adoption. In this study, an actuation triggered thermal exfoliation process is realized at a very low temperature of 200 o C and atmospheric pressure. The underlying mechanism is found to be similar to corn popping and attributed to the thermally-stimulated actuation and water molecules escape. It is found that after the exfoliation process, the resultant popped graphene oxide exhibits highly porous structures with the oxygen-containing groups being effectively removed, and has a specific capacitance of 120 F g -1 without any retention after 1500 CV cycles, demonstrating good electrochemical capacitance performance with excellent stability. The popping-like process can effectively reduce graphene oxide into 3D porous geaphene structures in one single-step process. This process is mild, short in time, environmental friendly and most importantly providing a scalable and easy method to produce large amount graphene-based assembly for potential capacitor applications.ε-Fe2O3, which is a rare phase of iron oxide Fe2O3, was first obtained as a pure phase by our research group in 2004. It exhibits a huge coercive field of 20 kOe at room temperature, and due to the strong magnetic anisotropy, this material shows millimeter wave absorption at a very high frequency of 182 GHz. 1 In this work, we report the theoretical studies on the electronic structures of ε-Fe2O3 to understand its huge coercivity. Synthesis of ε-Fe2O3 nanoparticles uses a combination technique of reverse-micelle and sol-gel techniques. The crystal structure is orthorhombic with four different Fe sites, A, B, C, and D sites, where A, and B sites are distorted octahedral, C site is a regular octahedral, and D site is a tetrahedral site. Using this crystal structure, we studied the electronic structure using first-principles calculations and molecular orbital calculations to understand the origin of the huge coercive field. 2 The density of states showed that ε-Fe2O3 is a chargetransfer type insulator with positive sublattice magnetizations at B and C sites and negative sublattice magnetizations at A and D sites, consistent with our previous study based on molecular field theory. 3 The charge density map showed a strong hybridization between Fe3d and O2p orbitals. Molecular orbital calculations indicated that this hybridization originates from the distorted coordination geometry of the Fe sites. This hybridization induces charge-transfer from O2p to Fe3d, which is assumed to create a non-zero orbital angular momentum, affecting the magnetic anisotropy of ε-Fe2O3.Aluminum alloys are important structural materials because of their high strength-weight ratio, high thermal and electrical conductivities, high corrosion-resistance, and low cost. With very low hydrogen solubility, aluminum alloys have the potential for hydrogen-storage application without suffering from the hydrogen-embrittlement problem typical of steels. For this application, the long-time mechanical performance of the materials under hydrogen environment must be understood. Large-scale atomistic simulations based on interatomic potentials enable studies of the fundamental behavior of hydrogen with aluminum (e.g., adsorption, absorption, diffusion) as well as the interactions between hydrogen and crystalline defects such as dislocations. These studies can guide constitutive models to accurately predict material deformation over long-time scales. Numerous aluminum interatomic potentials exist, but none capture energy and geometry trends of different phases, making them problematic for studying defects (e.g., dislocations, hydrogen segregation, etc). Furthermore, we have found that angular-independent potentials have difficulty capturing both elastic properties and the high stacking fault energy characteristic of aluminum’s face-centered-cubic (fcc) phase. Many literature angular-dependent potentials also poorly reproduce stacking fault energy due to inadequate parameterizations. In this work, we have developed an analytical bondorder potential (BOP) for aluminum. We show that this aluminum potential is transferrable to a variety of local configurations including defects and surfaces. More importantly, it simultaneously captures the elastic properties and stacking fault energy of the fcc phase. We are currently expanding our BOP to include both copper and hydrogen in an attempt to study hydrogen effects on Al-Cu alloys.W have developed molecular non-magnetic insulators which reversibly exhibits metallic properties with localized spins under light irradiation. Such materials can be applied to electromagnetic switches and sensors controlled by light. Such devices are advantageous over existing ones in terms of low energy consumptions and having both function of memory (magnetism) and calculation (conduction). Our strategy is exciting many CT transitions at a time by white light, causing a large amount of electron transfer between photochemical redox pairs. Since the radical anions of Ni(dmit)2 complex molecule, to which we pay particular attention, often produce Mott insulators, this strategy may correspond to “optical doping” to Mott insulators. Doping to Mott insulators is known for often leading to high-TC superconductors and other unusual physical properties demonstrated by cuprates and fullerides. For example, the methyl viologen (MV) salt, MV[Ni(dmit)2]2, exhibits higher conductivity under UV irradiation than that under dark by three orders of magnitude, and also exhibits metallic behavior under UV irradiation down to low temperature. The irradiation of vis-NIR light, which is intensely absorbed by the Ni(dmit)2 radical monoanions, does not lead to such high (photo)conductivity. This may be because the photoconductivity of standard mechanism produces carriers in the Ni(dmit)2 bands at the cost of charge disproportionation, while our CT-based photoconductivity can produce more carriers without such charge disproportionation. By clarifying the mechanism as well as synthesizing related compounds, we can make further steps towards new compounds with better performance, which will be applied to practical use in the future advanced information technology. Toshio Naito, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010In this talk, I will discuss precision manipulation, assembling, and actuation of nanoentities by electric tweezers for ultrasensitive biochemical detection, single-cell drug delivery, and bottom-up assembling of nano-electromechanical system (NEMS) devices. Electric tweezers are our recent invention, which utilize combined DC and AC electric fields to manipulate nanoentities in suspension. Nanowires can be transported in both the X and Y directions along prescribed trajectories with a precision of at least 150 nm and rotated with controlled angle, velocity (to at least 26000 rpm) and chirality. Leveraging the unique electric-tweezer manipulation, we designed, synthesized, assembled, and rotated arrays of plasmonic Raman nanosensors and investigated their innovative sensing enhancement mechanisms for single-molecule and location-predictable biochemical detection. We delivered cytokine functionalized nanowires to a single live cell amidst many and studied signal transduction mechanisms. We readily determined the electronic properties of various nanomaterials from their mechanical rotation in a noncontact and non-destructive manner. We bottom-up assembled and synchronously actuated arrays of NEMS devices such as rotary nanomotors and nano-oscillators using nanoparticles as building blocksThere have been continuing efforts simultaneously to explore the effects of various adsorbed guest atoms or molecules on graphene because potential applications and electronic transports properties experiments with graphene require contact with metal electrodes. Research interests in transition metal adsorption expand the ranges of applications from catalysis, spintronics to magnetic device. In this work, geometric stabilities, electronic and magnetic properties of low-coverage stable palladium (Pd) adsorbed graphene are studied based on first principles plane wave implemented in the QUANTUM ESPRESSO simulation package. It is found that single Pd adsorbing on top of carbon atom site is the most stable configuration. Moreover, the study reveals that the graphene with single Pd atom is metallic and non-magnetic. For palladium dimer, it is found that, depending on the configuration of the parallel or perpendicular Pd, two distinct situations with respect to magnetic behavior can be realized. For parallel configurations where the bonding is more strengthened, Pd dimer adsorbing on top of two carbon atoms site is the favored configuration and non-magnetic. Furthermore, the study also reveals that in spite of low coverage Pd dimer adsorbed graphene the system is metallic. This further reveals the possibility of using palladium atom on graphene for catalytic hydrogen storage. For perpendicular Pd configurations, reasonable magnetic moment was detected for depending on the strength of the Pd-graphene bond. These results demonstrate that the graphene electronic and magnetic properties can be effectively modified by Pd dimer metal adsorption and this may serve as a potential material in nanodevices applications.Oil and gas exploration, development and delivery processes are often associated with high temperature and high pressure applications in chemically aggressive conditions. This requires materials that have; (i) long-term thermal stability, (ii) high mechanical strength and dimensional stability, (iii) high resistance to abrasive and chemical wear, and (iv) low particle generation and low outgassing for reduced contamination. This requires new and innovative materials that possess a unique combination of properties. Over the years, a number of coatings have been developed to successfully deliver resistance to high temperatures, abrasive and wear resistance, as well as high strength and durability in a number of applications such as machining tools, automotive, and semiconductors. In such and similar applications, coatings have been known to have improved the wear performance and life of the coated part in their applications. While most of the currently available coatings have been developed to enhance the properties of cutting tools in the machine tool industry, nano-structured coatings can in principle be used for a variety of high temperature applications in the oil and gas industry. This paper explores the possibilities of designing, developing and optimizing nano-structured coatings that can be deposited on candidate mechanical components in a bid to enhance the mechanical properties and improve the degradation characteristics for new and innovative materials applications. A comprehensive study of the high temperature stability and degradation characterization of several advanced nanostructured coatings originally developed for tooling protection was carried out. Test samples were commercial prepared by means of the physical deposition technique (PVD). The aim of the study was to investigate the properties of several nanostructured coatings for innovative applications in the oil and gas industry. Results of the study indicate that it is possible to identify, develop and characterize coating compositions that possess various combinations of physical, chemical and mechanical properties for use in a number of new applications in the oil and gas industry.P nanoclusters are widely used as catalysts for various processes, such as oxidation reactions and catalytic reactions of organic molecules. To optimize the performance of the platinum catalyst it is important to understand the mechanisms of the catalytic reactions on a molecular level and to investigate how various parameters of the clusters, such as cluster’s size and shape, affect the rate of the reaction and the efficiency of the catalyst. In the current work, CO oxidation and methanol decomposition on platinum nanoclusters of various sizes and shapes were studied using the density functional theory (DFT). Obtained results are used to understand the role of various adsorption sites on the cluster and the differences between the various facets. The results of calculations suggest that clusters between one and two nm in size may provide better conditions for CO oxidation than clusters of other sizes, in agreement with previously published experimental data. However, methanol decomposition may occur faster on larger clusters. Sergey Dobrin, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010The high surface area of nanomaterials dictates that the interface with their surroundings is important in determining their properties or functionality. For example, all atoms in single-walled carbon nanotubes (SWCNTs) exist on the surface and, therefore, have excellent sensing capabilities. The interface of SWCNTs with their surroundings is also important to their application in polymer composites, devices, drug delivery, bioimaging and biosensing. Understanding and ultimately controlling these surface layers is important because of its influence on reactivity, adsorption of pollutants, and interaction with biological materials. SWCNT interfaces are often altered with surfactants to improve their dispersion in aqueous suspensions. While the surfactant surrounding the nanotube provides many benefits, the inability to alter or control this interface often limits the performance or functionality of the nanotube. A lack of information on the effect of the surrounding environment on SWCNT properties further complicates the development of processes to control these interfaces. I will discuss our efforts at characterizing and controlling SWCNT interfaces. I will show that emulsion-like microenvironments surrounding the nanotubes can be used to probe the interaction of molecules with the SWCNTs and coat the nanotubes with thin polymer shells, enabling control over the interfacial properties of the nanotubes. I will show how the ability to control these interfaces changes the retention behavior of SWCNTs onto agarose columns and may alter the toxicity of SWCNTs to various biological materials. Finally, I will show how these systems could provide new avenues for loading drugs within SWCNTs.Thermo mechanically treated steel is a high-strength steel having superior properties such as high weldability, strength, ductility and bendability. This research studies the different microstructures developed in Thermo Mechanically Treated (TMT) wire rod and plain wire rod at BSP, India, due to differences in their treatment and cooling processes, which results in better mechanical properties such as ultimate tensile strength (UTS), yield strength (YS) and ductility in TMT wire rod. In Wire Rod Mill, during thermo mechanical treatment of wires, the steel wires are made to pass through a specially designed water-cooling system where these wires are kept for such a period of time that the outer surface of wires become colder than the core, which remains hot. This creates a temperature gradient in the wires. When the wires are taken out of the cooling system, the heat flows from the core to the outer surface causing further tempering of steel wires thereby helping them to attain higher yield strength. During micro-structure study of the samples, it was observed that in TMT wire rod, the periphery consists of Tempered Martensite structure while the core is of Fine Ferrite and Pearlite. In case of the plain wire rod, the core and the periphery both consist of the Coarser Grains of Ferrite and Pearlite. Due to the presence of tempered martensite, the YS and UTS are higher in TMT as compared to plain wire rod. The finer grain in the TMT wire rod is also responsible for the higher YS and UTS as compared to the plain wire rod.T structure and properties of several poly(amidoamine) dendrimers have been studied extensively. Dendrimers are interesting candidates for designing colloidal drug delivery system through interaction with oppositely charged (anionic) surfactants. Dendrimer-based core-shell architectures for phase transfer processes have been obtained via covalent linking of hydrophobic alkyl chains to the polyfunctional core, followed by several purification steps. The present study was undertaken to prepare fatty acid/dendrimer complex by non covalent interaction containing doxorubicin. Formulations were prepared using alcoholic solution of palmitic acid (0.039 M moles) and 4.0G PAMAM dendrimer (0.0016 Mmoles). Solutions of dendrimer and palmitic acid were taken in 10 ml volumetric flask in 1:8, 1:16 and 1:32 equivalent molar ratio and volume was made up to 10 ml with water. The formulation was evaluated for transmittance, particle size etc. Formulations, differing in fatty acid (palmitic acid) composition were prepared by dilution method. Dendrimer containing compositions tend to form nanoparticles upon dilution. The core shell fatty acid and dendrimer complex formulations can be used for suitably controlled drug delivery of anticancer drugs. Pushpendra Kumar Tripathi, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010E is a simple, but efficient and versatile, technology to produce polymeric nanofibers for diverse applications. This technique has shown many advantages such as universality in processing polymeric materials, eases of controlling the fiber diameter and functionality, and flexibility to generate fibrous membranes of various geometries. Although the novel applications of electrospun nanofibers have been extensively explored, the technology development for mass electrospinning of nanofibers has been hampered. In most cases, nanofibers are electrospun in the form of nonwoven webs. Nanofiber yarns, nanofiber bundles having long continuous length and interlocked fibrous structure, are expected to create new opportunities to develop more complicated fibrous structures with well-defined three-dimensional architectures and better mechanical performance, but still remain difficulties to produce on large scale. In our recent study, we have developed needleless electrospinning systems to produce nanofiber nonwoven mats and nanofiber yarns. By examining the effect of various parameters on nanofiber/yarn diameter, fiber production rate and yarn twist, we have found that electric field and the distribution of electric field intensity on the fiber generator are important parameters to control the fiber quality and productivity but there are still some issues with electrospinning nanofiber yarns using needleless spinnerets. This talk introduces our recent research progress in these areas. Tong Lin, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010G scaffolds provide platform for the cells to grow and repair/regenerate the diseased or damaged tissue. For efficient functioning, the scaffolds are to assist the growth of the tissue in a required alignment or pattern. To date various conventional techniques have been widely used to fabricate tissue engineering (TE) scaffolds. However, the versatility of usage of scaffold materials and control over pore shape, size and interconnectivity remain ever facing challenges in the design and development of appropriate scaffolds. An innovative desktop robot based rapid prototyping (DRBRP) system has been developed that can create scaffolds virtually from any thermoplastic polymeric material with versatile patterns having controllable and fully interconnected pore networks. In this study, a range of materials have been experimented to produce 3D scaffolds with varieties of patterns. The hybrid design, which is rather considered to be a new concept in scaffold development, has also been introduced. The scaffolds were characterized in terms of physico-mechanical properties, and also tested for tissue generation via in vitro cell culture studies using various mammalian cells. Overall, the DRBRP system proved its efficacy in fabricating scaffolds using synthetic thermoplastic polymers with versatile patterns. The in vitro cell culture studies also demonstrated the biocompatibility and/or suitability of as-fabricated scaffolds for tissue engineering applications. Muhammad Enamul Hoque, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010The study of functional materials is an important issue in the field of solid state science. Up to date, we have reported various unique magnetic functionalities using cyano-bridged bimetallic assembly. 1-3 Furthermore, we have observed a photo-reversible metal-semiconductor phase transition at room temperature in λ-Ti3O5. 4 In addition, we have developed a pure phase of -iron oxide nanomaterials, which exhibit a gigantic magnetic coercive field and high frequency millimeter wave absorption. Photogmagnetism based on cyano-bridged bimetal assembly Spontaneous bulk magnetization due to light-induced spin-crossover was observed in a metal-organic framework (MOF) based on a three-dimensional Fe-Nb bimetallic assembly, Fe2[Nb(CN)8]·(4-pyridinealdoxime)8·2H2O 3 . This photomagnet showed magnetic phase transition at 20 K, which originates from the long-range magnetic ordering between the Fe II HS sites through −NC−Nb IV (S=1/2)−CN− bridge. Gigantic coercive field and high frequency millimeter wave absorption based on -Fe2O3 Rh-substituted ε-Fe2O3, ε-RhxFe2−xO3 nanomagnets was prepared by a nanoscale chemical synthesis. 6 ε-RhxFe2−xO3 nanomagnets exhibit a huge Hc of 27 kOe at room temperature. Furthermore, a crystallographically oriented sample recorded an Hc value of 31 kOe, which is the largest among metal-oxide-based magnets and is comparable to those of rareearth magnets. In addition, ε-RhxFe2−xO3 shows the highest zero-field ferromagnetic resonance frequency, resulting in high frequency millimeter wave absorption and magnetic rotation above 200 GHz. (1) S. Ohkoshi, et al., Nature Materials, 3, 857 (2004). (2) S. Ohkoshi and H. Tokoro, Accounts Chem. Res., 45, 1749 (2012). (3) S. Ohkoshi, et al., Nature Chemistry, 3, 564 (2011). (4) S. Ohkoshi, et al., Nature Chemistry, 2, 539 (2010). (5) S. Ohkoshi, et al., Angew. Chem. Int. Ed., 46, 8392 (2007). (6) A. Namai, et al., Nature Communications, 3, 1035 (2012).W report a novel approach to improve the resistive switching performance of metal oxide based memristors. In the first approach, the vertically aligned ZnO (NR) arrays were grown on transparent conductive glass by electrochemical deposition while CeO2 quantum dots (QDs) were prepared by a solvothermal method. Subsequently, the as-prepared CeO2 QDs were embedded into ZnO NRs array by dip-coating to obtain CeO2-ZnO nano-composite. Interestingly, such a device exhibits excellent resistive switching properties with much higher On/Off ratios, better uniformity and stability over the pure ZnO and CeO2 nanostructures. The origin of resistive switching was studied and the role of hetero-interface was discussed. Secondly, selfassembled CeO2 nanocubes based resistive switching device was fabricated by hydrothermal process. The device was proven to exhibit excellent resistive switching performance. The origin of switching behaviour on the basis of filament model and inter cube junctions was presented. The present devices demonstrate to have the potential for next generation non-volatile memory applications. Adnan Younis et al., J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010B capillaries (microvessels) play a critical role in tissue formation and function as they ensure proper nutrient and oxygen delivery to tissues. Indeed, microvascular dysfunctions in the form of regression and chronic inflammation lead to severe pathologies such as cardiovascular diseases and chronic wounds. Conventional microvascular normalization strategies involve systemic administration of high doses of pharmacological or biological agents that often cause drug tolerance and/or undesirable side effects. To address these limitations, our lab is developing injectable site‐targeting nanoparticles that can selectively home to microvascular defect sites and locally deliver low doses of a drug to achieve effective microvascular normalization. The simultaneous increase in drug half‐life, control of the rate of drug release and reduction in toxic side effects achieved by this targeted nanotherapeutic approach makes it superior to conventional strategies. Specifically, these therapeutic nanoparticles achieve microvascular normalization by increasing the local production of nitric oxide (NO). NO is a gaseous molecule that promotes capillary formation and function and depletion in NO levels leads to various microvascular complications. To enhance NO production, the nanoparticles are loaded with a conventional clinically‐used NO‐enhancing vasodilatory drug that, we have recently shown, also exhibit novel anti‐inflammatory and vasculogenic properties. Finally, the site‐targeting capability is achieved by modifying the surface of drug‐loaded nanoparticles with an antibody for E‐selectin, a cell‐surface marker that is overexpressed at sites of microvascular defects. Identification of the unique microvascular normalization properties of a clinically‐approved drug and development of a nanotherapeutic approach for its targeted delivery to vascular defect sites may lead to superior clinical management of microvascular dysfunctions and the related pathological conditions. Kaustabh Ghosh, J Material Sci Eng 2013, 2:4 http://dx.doi.org/10.4172/2169-0022.S1.010