A Coordinated Heuristic Approach for Virtual Network Embedding in Cloud Infrastructure

( Nahid Hamzehee Nia ),( Sepideh Adabi ),( Majid Nikougoftar Nategh ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.5

A major challenge in cloud infrastructure is the efficient allocation of virtual network elements on top of substrate network elements. Path algebra is a mathematical framework which allows the validation and convergence analysis of the mono-constraint or multi-constraint routing problems independently of the network topology or size. The present study proposes a new heuristic approach based on mathematical framework "paths algebra" to map virtual nodes and links to substrate nodes and paths in cloud. In this approach, we define a measure criterion to rank the substrate nodes, and map the virtual nodes to substrate nodes according to their ranks by using a greedy algorithm. In addition, considering multi-constraint routing in virtual link mapping stage, the used paths algebra framework allows a more flexible and extendable embedding. Obtained results of simulations show appropriate improvement in acceptance ratio of virtual networks and cost incurred by the infrastructure networks.

Magnetic field-induced improvement in O2/N2 gas separation applications of simultaneously co-casted superparamagnetic mixed matrix membranes

Nahid Nikpour,Amir H. Montazer,Ali Khayatian 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.105 No.-

For industrial purposes and current challenges facing the world, the selective separation of oxygen andnitrogen gases from the air by polymer mixed matrix membranes is crucial. Due to the diamagnetic natureof water molecules used in the fabrication of the polymer membranes, the magnetic field (H) mayaffect the resulting separation performance. Here, using a simultaneous co-casting method, empty andsuperparamagnetic Fe3O4 nanoparticle-filled double-layer polyethersulfone (PES)/Pebax 1657 mixedmatrix membranes are fabricated under different external magnetic field intensities in the range ofH = 0–5000 Oe. The O2 and N2 permeances of the PES/Pebax membranes are found to increase withincreasing the magnetic field intensity, arising from an enhancement in the polymer chain mobility. The Fe3O4 nanoparticles form thick root-like superparamagnetic channels on the double-layer PES/Pebax surface at a magnetic field intensity of 4000 Oe, resulting in an O2/ N2 ideal selectivity of 3.59at a feed gas pressure of 10 bar. This indicates an improvement of 40% in the selectivity compared to asingle-layer Pebax membrane filled with Fe3O4 nanoparticles.

Extensive Venous Tumor Thrombi in a Case of Malignant Melanoma: Role of 18F FDG PET/CT

Nahid Yaghoobi,Raheleh Hedayati,Hadi Malek,Mehdi Maghsudi 대한핵의학회 2022 핵의학 분자영상 Vol.56 No.5

The 18F-FDG PET/CT imaging is a non-invasive modality for diagnosis and staging of metastatic melanoma. Venous thromboembolism (VTE) is a common complication of cancers, which needs anticoagulant therapy. Tumor thrombosis (TT), on the other hand, is an infrequent complication of solid malignancies that may need aggressive management. Accurate diagnosis of TT and its differentiation from VTE may change patient management and avoid unnecessary anticoagulation treatment. The objective of this case is to introduce a patient with malignant melanoma presenting with extensive venous tumor thrombi with intense FDG uptake.

D-Limonene as a green bio-solvent for dispersive liquid–liquid microextraction of β-cyclodextrin followed by spectrophotometric determination

Nahid Pourreza,Tina Naghdi 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.51 No.-

In this paper D-limonene and b-carotene are introduced as two natural products in a dispersive liquid–liquid microextraction (DLLME) method for spectrophotometric determination of b-cyclodextrin (b-CD). Dissolved b-carotene in D-limonene exhibits strong absorption exhibits strong absorption intensity afterperforming. The absorption intensity of the extracted phase is increased in the presence of b-CD due to itsinteraction (complex formation) with b-carotene. This increase in the absorbance of the extracted phaseis related to the b-CD concentration and was utilized as an analytical signal for determination of b-CD. The effect of chemical variables such as pH of the sample solution, nature and volume of dispersivesolvent, volume of extraction solvent and extraction time on the DLLME method was studied andoptimum conditions were established. The calibration curve was linear in the range of 110 4–6 10 3 mol L 1 (r = 0.9956) with a limit of detection 410 5 mol L 1. The relative standard deviation foreight replicate determinations of 110 3 mol L 1 and 510 3 mol L 1 of b-CD was 1.82% and 0.88%respectively. The proposed method was successfully applied to the determination of b-CD in spikedwater and pharmaceutical samples and good recoveries in the range of 94.2–108.0% were obtained.

Relationships of the Vitamin D and Platelet Indices in Sjögren’s Syndrome

Nahide Ekici Günay,İrfan Buğday,Tayfun Akalın 대한임상검사과학회 2018 대한임상검사과학회지(KJCLS) Vol.50 No.4

Primer Sjögren’s Syndrome (pSS) is an autoimmune/inflammatory illness. The platelet indices (PIs) indicate the inflammatory response and activity/severity of many diseases. A vitamin D deficiency is accompanied by the increased tendency of autoimmune diseases. This study investigated whether the vitamin D levels are related to the altered platelet indices in pSS. A total of 261 individuals were included in this analytical cross-sectional study. The laboratory data of pSS patients were evaluated and the relationship between the PIs and vitamin D status was examined. According to these findings, in patients with pSS, the vitamin D levels were lower than the healthy control group (P<0.05). The vitamin D levels were negatively associated with PDW (P=0.012), but positively correlated with PCT (P<0.001). The cut-off point was obtained with receiver operating characteristics (ROC) curves for PDW: 12.53 (AUC 0.921, sensitivity 90%, specificity 85%), for PCT; 0.29 (AUC 0.660, sensitivity 68%, specificity 55%). In multivariate linear regression analysis, the most significant parameters for the effects of PDW are the following: vitamin D (=−0.373; t=−2.626; sig.=0.013) and plateletcrit (=−0.308; t=−2.13; sig.=0.040). A vitamin D deficiency may be accompanied by changes in PIs in pSS. A higher PDW and lower PCT supports the underlying inflammation, which may be vitamin D related useful parameters to consider in approaching to pSS.

Gene cloning, bacterial expression, and purification of calreticulin from Anopheles stephensi (AsCRT)

Nahid BORHANI,Mansour HEIDARI,Hamid R. BASSERI 한국곤충학회 2012 Entomological Research Vol.42 No.1

During the invasion of Plasmodium ookinetes to the mosquito midgut epithelium, several proteins or glycoproteins are involved. Recent study has shown that the calreticulin (CRT) of the midgut from Anopheles albimanus can bind to the protein receptor Pvs25 on surface of Plasmodium vivax ookinetes. Thus, in order to get more insight into the potential roles of Anopheles stephensi calreticulin (AsCRT) in the midgut, we amplified and cloned the full-length of calreticulin coding sequence from Anopheles stephensi. The AsCRT consists of 1221 bp nucleic acids with one open reading frame (ORF) encoding 406 amino acids and an apparent molecular weight around 46 KDa. Subsequently, the recombinant calreticulin as Glutathione S-transferase (GST) fusion in pGEX -6p-1 expression vector (GST-AsCRT) was produced in the prokaryotic system under optimum conditions. GST-AsCRT fusion protein has a molecular weight around 73 KDa. The recombinant protein was detected byWestern blotting using a rabbit anti-GST polyclonal antibody. Here, we report via single protein purification procedure using MagneGST beads, 25 mg of the recombinant protein was obtained per liter of bacterial culture. This is the first report describing the heterologous expression of Anopheles stephensi calreticulin in the prokaryotic system. The production of this recombinant protein will now allow us to further investigate AsCRT molecular protein analyses, characterization of physiochemical properties, as well as interaction between calreticulin and plasmodium protein surface.

Mechanical Properties of Multiscale Graphene Oxide/Basalt Fiber/Epoxy Composites

Nahid Jamali,Hamed Khosravi,Ali Reza Rezvani,Esmaeil Tohidlou 한국섬유공학회 2019 Fibers and polymers Vol.20 No.1

This work was carried out to study the effects of silane functionalization of graphene oxide (GO) nanoplatelets and their loadings on the mechanical properties of basalt fiber (BF)/epoxy composites. At first, the GO nanoplatelets were organically modified by grafting of N-(3-trimethoxysilylpropyl)ethylenediamine (3-TMSPED) compound. The Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), and thermal gravimetric analysis(TGA) results demonstrated that silane compound can be covalently grafted to the surface of GO. The multiscale silanized graphene oxide (SGO)/BF/epoxy composites with various weight percentages of SGO in the matrix (0-0.5 wt.% in the step of 0.1) were fabricated. According to the experimental data, the 0.4 wt.% SGO-filled composite showed the maximum improvement by 18 %, 59 %, and 61 % in the tensile, flexural and compressive strengths of BF/epoxy composite, while the maximum improvement by 46 %, 54 %, and 66 % in the tensile, flexural and compressive moduli, respectively was observed for the 0.5 wt.% SGO-filled composite. Additionally, the SGO was more effective in mechanical property enhancement of fibrous composites in comparison with GO, due to its silane-functionalization. From the fracture surface examination of the specimens, it was found that the incorporation of GO or SGO improved the BF-epoxy interfacial bonding. A theoretical model based on Euler-Bernoulli beam-based method was utilized to predict the compressive properties of composites, which was in an excellent agreement with the experimental data.

Distribution of Aortic Root Calcium in Relation to Frame Expansion and Paravalvular Leakage After Transcatheter Aortic Valve Implantation (TAVI): An Observational Study Using a Patient-specific Contrast Attenuation Coefficient for Calcium Definition and

Nahid El Faquir,Quinten Wolff,Rafi Sakhi,Ben Ren,Zouhair Rahhab,Sander van Weenen,Patrick Geeve,Ricardo P J Budde,Eric Boersma,Joost Daemen,Nicolas M van Mieghem,Peter P de Jaegere 한국심초음파학회 2022 Journal of Cardiovascular Imaging (J Cardiovasc Im Vol.30 No.4

BACKGROUND: Calcium is a determinant of paravalvular leakage (PVL) after transcatheter aortic valve implantation (TAVI). This is based on a fixed contrast attenuation value while X-ray attenuation is patient-dependent and without considering frame expansion and PVL location. We examined the role of calcium in (site-specific) PVL after TAVI using a patient-specific contrast attenuation coefficient combined with frame expansion. METHODS: 57 patients were included with baseline CT, post-TAVI transthoracic echocardiography and rotational angiography (R-angio). Calcium load was assessed using a patient-specific contrast attenuation coefficient. Baseline CT and post-TAVI R-angio were fused to assess frame expansion. PVL was assessed by a core lab. RESULTS: Overall, the highest calcium load was at the non-coronary-cusp-region (NCR, 436 mm3) vs. the right-coronary-cusp-region (RCR, 233 mm3) and the left-coronary-cusp-region (LCR, 244 mm3), p < 0.001. Calcium load was higher in patients with vs. without PVL (1,137 vs. 742 mm3, p = 0.012) and was an independent predictor of PVL (odds ratio, 4.83, p = 0.004). PVL was seen most often in the LCR (39% vs. 21% [RCR] and 19% [NCR]). The degree of frame expansion was 71% at the NCR, 70% at the RCR and 74% at the LCR without difference between patients with or without PVL. CONCLUSIONS: Calcium load was higher in patients with PVL and was an independent predictor of PVL. While calcium was predominantly seen at the NCR, PVL was most often at the LCR. These findings indicate that in addition to calcium, specific anatomic features play a role in PVL after TAVI.

Fabrication of AuNPs into alginate biopolymer and functionalized by thiourea as a film shape probe for palladium(II) sensing

Nahid Pourreza,Parichehr Abasipanah,Matineh Ghomi 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.100 No.-

A simple process was developed for the fabrication of alginate biopolymerfilm embedded by thiourea-functionalized AuNPs (thiourea/AuNPs) for palladium(II) detection. A mixture of sodium alginate andHAuCl4 was prepared as the main matrix and the AuNPs were in situ synthesized in alkali media providedby borax. The AuNPs entrapped in the alginate network were functionalized by thiourea and fabricated asa transparentfilm. The characteristics of thiourea/AuNPs alginate biopolymerfilm were investigated byTransmission electron microscopy (TEM), Energy dispersive X-ray analysis (EDX) and UV–visspectrophotometry. The UV–vis absorption spectrum showed the maximum wavelength of thiourea/AuNPs was at 530 nm. The effect of various parameters such as pH and thiourea concentration on thesensing of palladium(II) ions was investigated. The prepared alginate biopolymerfilm showed goodstability over the time. The calibration graph was linear in the range of 0.05 2.10 mg mL 1 with adetection limit of 0.038 mg mL 1. The relative standard deviation (n = 10) for 0.6 and 1.2 mg mL 1 ofpalladium(II) was 4.6% and 3.5%, respectively. The sensing system was successfully applied for thedetermination of palladium in walnut leaves, wastewater, dental amalgam, and ceramic capacitorsamples.

Silicon carbide nanoparticles as an adsorbent for solid phase extraction of lead and determination by flame atomic absorption spectrometry

Nahid Pourreza,Tina Naghdi 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.5

Silicon carbide nanoparticles were applied as a new solid phase adsorbent for preconcentration of lead ions. Pb(II) ions are adsorbed on silicon carbide nanoparticles, eluted with nitric acid and determined by flame atomic absorption spectrometry. The solid phase extraction conditions were optimized. The calibration graph was linear in the range of 2–150 ng mL-1 (r = 0.9995) with a detection limit of 0.4 ng mL-1. The relative standard deviation for eight measurements of 20 ng mL-1 of Pb(II) was 1.3%. The adsorption capacity was 156.2 mg g-1of Pb(II). The method was applied to determination of Pb(II) in different samples.