Influence of substrate annealing on inducing Ti3+ and oxygen vacancy in TiO2 thin films deposited via RF magnetron sputtering

Nano-crystalline TiO2 has been prepared by RF magnetron sputtering at varied substrate temperatures ranging from 200 to 500 °C. The alteration of oxygen and titanium atom in TiO2 at uppermost surface is clearly observed on the effect of annealing temperature by Auger Electron Spectroscopy (AES) technique. The measurement of peak to peak value of Ti and O transition line at 400 °C indicates the surface chemical state of O2 in TiO2 thin films defect at surface and Fermi level was analyzed using the X-Ray Photoelectron Spectroscopy (XPS). The Ti 2p observation of pre and post surface treatment shows the concentration of Ti3+ is seven times higher after post sputtered for sample 200 °C. Ti3+ decrease by increasing temperature. The Ti3+-oxygen vacancy which also assigned as Ti2O3 occurred in all sample, yet sample deposited at 400 °C gives nearest binding energy for Ti2O3. This observation also supported by The Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) analysis which shows highest total ion count for positive polarity is O+ for sample at 300 °C and Ti ion dominant is Ti2O3 + for sample at 400 °C. Based on the analyses, it is clearly seen that high defect of Ti3+-oxygen vacancy which is located between surface layer and fermi level state, this defect levels was created at surface layer at low annealing temperature. However, increasing temperature leads to defect creation on bellow surface layer which consider as within fermi level laye

Acute-on-chronic Liver Failure: MELD Score 30-day Mortality Predictability and Etiology in a Pakistani Population

Background: Cirrhosis is a pathological condition that ultimately leads to liver failure. Acute on chronic liver failure (ACLF) has a high short term mortality rate. Viral hepatitis is the most common cause of liver failure in our local population. We carried out this study to identity the 30-day mortality and etiology of patients presenting with ACLF using Model for End-Stage Liver Disease (MELD) score predictability. Methodology: This was a descriptive case series, conducted at Sheikh Zayed Hospital, Lahore, Pakistan from January 31, 2018 to July 30, 2018. One hundred and eighty five patients who met the inclusion criteria were enrolled using 95% confidence level and 4% margin of error. Data was entered and analyzed with SPSS version 23.0. Numerical variables including age was presented by Mean ± S.D. Categorical variables i.e. gender, etiology of acute-on-chronic liver failure and 30-day mortality were presented by frequency and percentage. Data was stratified for age, gender, duration of chronic liver disease and MELD grade to address the effect modifiers. Post-stratification chi-square test was calculated using 95% significance (p≤0.05). Results: Majority of the enrolled patients were male (74.6%) while only 25.4% of the patients were female. One hundred and thirty patients (70.3%) had underlying viral hepatitis while twelve patients (6.5%) and forty three patients (23.2%) presented with alcoholic liver disease and drug-induced ACLF, respectively. Eighty patients (43.2%) died within 30 days of admission.The 30-day mortality with respect to MELD grade was statistically significant (p<0.001) with the highest mortality noted in grade-IV and thirty five patients (43.8%) dying within 30 days of admission (p<0.001). Grade-II and III MELD scores also contributed to the 30-day mortality with twenty three patients (28.8%) and nineteen patients (23.8%) dying within 30 days of admission (p<0.001). Conclusion: MELD scores are able to accurately predict the short-term mortality in patients with ACLF and viral hepatitis was the most common etiology in our population. Early detection and use of appropriate prognostic models may alleviate mortality and morbidity in paitents with ACLF

Zinc Oxide Nanostructures for Efficient Energy Conversion in Organic Solar Cell

We present a new approach of solution-processed using zinc oxide (ZnO) nanostructures as extraction layer material for organic solar cells. It is low chemical reaction compatibility with all types of organic blends and its good adhesion to both surfaces of ITO/glass substrate and the active layer (blends). Parameters such as the thickness and the morphology of the films were investigated to prove that these factors greatly affect the efficiency of organic solar cells. In this work, ZnO layer with thickness of approximately 53 nm was used as an interlayer to prevent pin-holes between the electrode and the polymer layer. The polymer layer was coated on the ZnO layer with the thickness of about 150 nm. The thick polymer layer will form a non-uniform surface because of the solvent, 1-2dichlorobenzene will etch away some region of the polymer layer and forming pin-holes. ZnO nanostructures layer was used to prevent pin-holes between the polymer layer and electrode. From the surface morphology of ZnO layer, it shows a uniform surface with particle grain size obtained between 50 -100 nm. The presence of the interlayer has a positive effect on the electrical characteristics of the solar cells. It was found that an organic solar cell with thickness less than 150 nm shows the optimum performance with efficiency of 0.0067% and Fill Factor (FF) of about 19.73

A cognitive radio-based fully blind multihop rendezvous protocol for unknown environments

In Cognitive Radio networking, the blind rendezvous problem is when two or more nodes must establish a link, but where they have no predefined schedule or common control channel for doing so. The problem becomes more challenging when the information about the existence of other nodes in the network, their topology, and primary user activity are also unknown, identified here as a fully blind rendezvous problem. In this paper, a novel and fully blind multihop (FBM) rendezvous framework is proposed with an extended modular clock algorithm (EMCA). The EMCA-FBM is a fully blind multihop rendezvous protocol as it assumes the number of nodes, primary radio activity and topology information as unknown. It is shown to work with different Cognitive Radio operating policies to achieve adaptiveness towards the unknown primary radio activity, and self-organization for autonomously handling the rendezvous process by using transmission schedules. It is capable of working without any information of neighbor nodes and terminating the rendezvous process whenever all or sufficient nodes are discovered. The proposed FBM is also shown to work as a general framework to extend existing single hop rendezvous protocols to work as a multihop rendezvous protocol. In comparison with other modified blind rendezvous strategies for multihop network, the combination of the proposed EMCA-FBM protocol and operating policies is shown to be effective in improving the average time to rendezvous (up to 70%) and neighbor discovery accuracy (almost 100%) while reducing harmful interference

Experimental evaluation of a software defined radio-based prototype for a disaster response cellular network

In post disaster situations it is vital to restore voice and data communication services quickly. Currently, portable wireless systems are used as a temporary solution. However, these solutions have a lengthy setup, limited coverage, and typically require the use of expensive satellite backhaul. Solutions based on cognitive radio mesh networks have been proposed, to exploit self-configuration and spectrum agility. To evaluate their potential, we build a software-radio-based prototype for a multi-cell network that uses an IEEE 802.11's unlicensed wireless communication band for backhaul, and an open-source GSM stack for access. The prototype provides voice communication services. We evaluate the prototype in an open environment. We demonstrate that under the right conditions, the system can support large numbers of simultaneous calls with acceptable quality. However, when the unlicensed band is heavily used, call quality quickly degrades because of interference on the backhaul link. We conclude that in order to provide acceptable quality of service it is desirable to exploit idle licensed spectrum for backhaul communication between base stations

Cognitive radio policy-based adaptive blind rendezvous protocols for disaster response

In disaster scenarios, with damaged network infrastructure, cognitive radio (CR) can be used to provide temporary network access in the first few hours. Since spectrum occupancy will be unknown, the radios must rely on spectrum sensing and opportunistic access. An initial goal is to establish rendezvous between CR nodes to set up the network. The unknown primary radio (PR) activity and CR node topology makes this a challenging task. Existing blind rendezvous strategies provide guarantees on time to rendezvous, but assume channels with no PR activity and no external interferers. To handle this problem of blind multi-node rendezvous in the presence of primary users, we propose an Extended Modular Clock Algorithm which abandons the guarantee on time to rendezvous, an information exchange mechanism for the multi-node problem, and various cognitive radio operating policies. We show that the adapted protocols can achieve up to 80% improvement in the expected time to rendezvous and reduce the harmful interference caused to the primary radio

Changes in the Demographic and Clinicopathological Characteristics of Thyroid Cancer : A Population-Based Investigation in Algeria, 1993-2013

Peer reviewedPostprintPublisher PD

Cognitive radio for disaster response networks: survey, potential, and challenges

In the wake of a natural or man-made disaster, restoration of telecommunications is essential. First responders must coordinate their responses, immediate casualties require assistance, and all affected citizens may need to access information and contact friends and relatives. Existing access and core infrastructure may be damaged or destroyed, so to support the required services, new infrastructure must be rapidly deployed and integrated with undamaged resources still in place. This new equipment should be flexible enough to interoperate with legacy systems and heterogeneous technologies. The ability to selforganize is essential in order to minimize any delays associated with manual configuration. Finally, it must be robust and reliable enough to support mission-critical applications. Wireless systems can be more easily reconfigured than wired solutions to adapt to the various changes in the operating environment that can occur in a disaster scenario. A cognitive radio is one that can observe its operating environment, make decisions and reconfigure in response to these observations, and learn from experience. This article examines the use of cognitive radio technologies for disaster response networks and shows that they are ideally suited to fulfill the unique requirements of these networks. Key enabling technologies for realizing real-world cognitive radio networks for disaster response are discussed and core challenges are examined

Rapid Determination of Non-steroidal Anti-inflammatory Drugs in Aquatic Matrices by Two-phase Micro-electrodriven Membrane Extraction Combined with Liquid Chromatography

Two-phase micro-electrodriven membrane extraction (EME) procedure for the pre-concentration of selected non-steroidal anti-inflammatory drugs (NSAIDs) in aquatic matrices was investigated. Agarose film was used as interface between donor and acceptor phase in EME which allowed for selective extraction of the analytes prior to high performance liquid chromatography-ultraviolet detection. Charged analytes were transported from basic aqueous sample solution through agarose film into 1-octanol as an acceptor phase at 9 V potential. Response surface methodology in conjunction with the central composite design showed good correlations between extraction time and applied voltage (R 2 > 0.9358). Under optimized extraction conditions, the method showed good linearity in the concentration range of 0.5-500 μg L -1 with coefficients of determination, r 2 ≥ 0.9942 and good limits of detection (0.14-0.42 μg L -1) and limits of quantification (0.52-1.21 μg L -1). The results also showed high enrichment factors (62-86) and good relative recoveries (72-114%) with acceptable reproducibilities (RSDs ≤ 7.5% n = 3). The method was successfully applied to the determination of NSAIDs from tap water and river water samples. The proposed method proved to be rapid, simple and requires low voltage and minute amounts of organic solvent, thus environmentally friendly

Investigation on the aerosol performance of dry powder inhalation hypromellose capsules with different lubricant levels

HPMC capsules are made by a dipping process and a surface lubricant for the mould pins is an essential processing aid for removing dried capsules shells. For the purpose of this study, the level was determined by quantifying methyloleate (MO) a component found in the lubricant but not in the hypromellose capsules. Here we investigated the influence of the lubricant, low (10.81 μg/capsule = 60 mg/kg MO), medium (15.97 μg/capsule = 90 mg/kg MO) and high (23.23 μg/capsule = 127 mg/kg MO) content on powder (binary mixture of salbutamol: lactose, 1:50 w/w) aerosolization properties was investigated. Results indicated significantly lower emitted dose from capsules with 60 mg/kg MO. Furthermore, the 90 and 127 mg/kg MO level of lubricant capsules produced almost double the Fine Particle Dose & Fine Particle Fraction compared with the low level of lubricant. The data indicates that lubricant level within capsules has an influence on deposition profiles and amount of drug remaining in capsule and inhaler device after actuation. It is suggested lubricant levels greater than 60 mg/kg MO per capsule are required to minimise powder retention within capsules and maximise deposition profiles. AFM (atomic force microscopy) data suggest that internal surface roughness may be related with this phenomena