Browse publications by year: 2014

Fulltext Review of the socket design and interface pressure measurement for transtibial prosthesis

Pirouzi G, Abu Osman NA, Eshraghi A, Ali S, Gholizadeh H, Wan Abas WA

ScientificWorldJournal, 2014;2014:849073.
PMID: 25197716 DOI: 10.1155/2014/849073

Socket is an important part of every prosthetic limb as an interface between the residual limb and prosthetic components. Biomechanics of socket-residual limb interface, especially the pressure and force distribution, have effect on patient satisfaction and function. This paper aimed to review and evaluate studies conducted in the last decades on the design of socket, in-socket interface pressure measurement, and socket biomechanics. Literature was searched to find related keywords with transtibial amputation, socket-residual limb interface, socket measurement, socket design, modeling, computational modeling, and suspension system. In accordance with the selection criteria, 19 articles were selected for further analysis. It was revealed that pressure and stress have been studied in the last decaeds, but quantitative evaluations remain inapplicable in clinical settings. This study also illustrates prevailing systems, which may facilitate improvements in socket design for improved quality of life for individuals ambulating with transtibial prosthesis. It is hoped that the review will better facilitate the understanding and determine the clinical relevance of quantitative evaluations.

MeSH terms: Artificial Limbs*; Biomechanical Phenomena; Humans; Pressure*; Prosthesis Design/methods*; Patient Satisfaction; Finite Element Analysis; Bioengineering/methods*
Fulltext Morphological characterization and assessment of genetic variability, character association, and divergence in soybean mutants

Malek MA, Rafii MY, Shahida Sharmin Afroz M, Nath UK, Mondal MM

ScientificWorldJournal, 2014;2014:968796.
PMID: 25197722 DOI: 10.1155/2014/968796

Genetic diversity is important for crop improvement. An experiment was conducted during 2011 to study genetic variability, character association, and genetic diversity among 27 soybean mutants and four mother genotypes. Analysis of variance revealed significant differences among the mutants and mothers for nine morphological traits. Eighteen mutants performed superiorly to their mothers in respect to seed yield and some morphological traits including yield attributes. Narrow differences between phenotypic and genotypic coefficients of variation (PCV and GCV) for most of the characters revealed less environmental influence on their expression. High values of heritability and genetic advance with high GCV for branch number, plant height, pod number, and seed weight can be considered as favorable attributes for soybean improvement through phenotypic selection and high expected genetic gain can be achieved. Pod and seed number and maturity period appeared to be the first order traits for higher yield and priority should be given in selection due to their strong associations and high magnitudes of direct effects on yield. Cluster analysis grouped 31 genotypes into five groups at the coefficient value of 235. The mutants/genotypes from cluster I and cluster II could be used for hybridization program with the mutants of clusters IV and V in order to develop high yielding mutant-derived soybean varieties for further improvement.

MeSH terms: Agriculture/methods; Analysis of Variance; Bangladesh; Breeding/methods; Genotype; Mutation/genetics; Phenotype*; Seeds/growth & development; Soybeans/anatomy & histology*; Soybeans/classification; Soybeans/genetics*; Soybeans/growth & development; Genetic Variation*; Cluster Analysis; Quantitative Trait, Heritable
Fulltext A clinical prediction tool for targeted pre-antiretroviral therapy creatinine testing applied to the TREAT Asia HIV observational database cohort

Boettiger DC, Saphonn V, Lee MP, Phanuphak P, Pham TT, Heng Sim BL, et al.

J Acquir Immune Defic Syndr, 2014 Dec 01;67(4):e131-3.
PMID: 25197829 DOI: 10.1097/QAI.0000000000000338
MeSH terms: Adenine/analogs & derivatives*; Creatinine/urine*; Decision Support Techniques*; Female; Humans; Kidney Diseases/chemically induced*; Male; Clinical Medicine/methods*; HIV Infections/drug therapy*; Anti-HIV Agents/adverse effects*; Organophosphonates/adverse effects*
Fulltext Hydrogel polysaccharides of tamarind and xanthan to formulate hydrodynamically balanced matrix tablets of famotidine

Razavi M, Nyamathulla S, Karimian H, Moghadamtousi SZ, Noordin MI

Molecules, 2014;19(9):13909-31.
PMID: 25197930 DOI: 10.3390/molecules190913909

The gastroretentive dosage form of famotidine was modified using tamarind seed powders to prolong the gastric retention time. Tamarind seeds were used in two different forms having different swelling and gelling properties: with husk (TSP) or without husk (TKP). TKP (TKP1 to TKP 6) and TSP (TSP1 to TSP 6) series were prepared using tamarind powder:xanthan in the ratios of 5:0, 4:1, 3:2, 2:3, 1:4, 0:5, respectively. The matrix tablets were prepared by the wet granulation method and evaluated for pharmacopoeial requirements. TKP2 was the optimum formulation as it had a short floating lag time (FLT<30 s) and more than 98.5% drug release in 12 h. The dissolution data were fitted to popular mathematical models to assess the mechanism of drug release, and the optimum formulation showed a predominant first order release and diffusion mechanism. It was concluded that the TKP2 prepared using tamarind kernel powder:xanthan (4:1) was the optimum formulation with shortest floating lag time and more than 90% release in the determined period of time.

MeSH terms: Calorimetry, Differential Scanning; Delayed-Action Preparations/chemistry; Hydrogen-Ion Concentration; Kinetics; Polysaccharides, Bacterial/chemistry*; Viscosity; X-Ray Diffraction; Famotidine/chemistry*; Spectroscopy, Fourier Transform Infrared; Hydrogels/chemistry*; Plant Preparations/chemistry; Tamarindus/chemistry*
Antioxidant and α-glucosidase inhibitory activities of 40 tropical juices from Malaysia and identification of phenolics from the bioactive fruit juices of Barringtonia racemosa and Phyllanthus acidus

Sulaiman SF, Ooi KL

J Agric Food Chem, 2014 Oct 1;62(39):9576-85.
PMID: 25198055 DOI: 10.1021/jf502912t

The present study compared pH, total soluble solids, vitamin C, and total phenolic contents, antioxidant activities, and α-glucosidase inhibitory activities of 40 fresh juices. The juice of Baccaurea polyneura showed the highest yield (74.17 ± 1.44%) and total soluble solids (32.83 ± 0.27 °Brix). The highest and lowest pH values were respectively measured from the juices of Dimocarpus longan (6.87 ± 0.01) and Averrhoa bilimbi (1.67 ± 0.67). The juice of Psidium guajava gave the highest total phenolic (857.24 ± 12.65 μg GAE/g sample) and vitamin C contents (590.31 ± 7.44 μg AAE/g sample). The juice of Phyllanthus acidus with moderate contents of total phenolics and vitamin C was found to exhibit the greatest scavenging (613.71 ± 2.59 μg VCEAC/g sample), reducing (2784.89 ± 3.93 μg TEAC/g sample), and α-glucosidase inhibitory activities (95.37 ± 0.15%). The juice of Barringtonia racemosa was ranked second in the activities and total phenolic content. Gallic and ellagic acids, which were quantified as the major phenolics of the respective juices, are suggested to be the main contributors to the antioxidant activities. The α-glucosidase inhibitory activity of the juices could be derived from myricetin and quercetin (that were previously reported as potent α-glucosidase inhibitors) in the hydrolyzed juice extracts. The juice of Syzygium samarangense, which was found to be highest in metal chelating activity (82.28 ± 0.10%), also was found to have these phenolics.

MeSH terms: alpha-Glucosidases/chemistry; Antioxidants/chemistry*; Beverages/analysis*; Fruit/chemistry; Kinetics; Malaysia; Plant Extracts/chemistry*; Molecular Structure; Phenol/chemistry*; Phyllanthus/chemistry*; Barringtonia/chemistry*; Glycoside Hydrolase Inhibitors/chemistry*
Directed assembly of bifunctional silica-iron oxide nanocomposite with open shell structure

Che HX, Yeap SP, Osman MS, Ahmad AL, Lim J

ACS Appl Mater Interfaces, 2014 Oct 8;6(19):16508-18.
PMID: 25198872 DOI: 10.1021/am5050949

The synthesis of nanocomposite with controlled surface morphology plays a key role for pollutant removal from aqueous environments. The influence of the molecular size of the polyelectrolyte in synthesizing silica-iron oxide core-shell nanocomposite with open shell structure was investigated by using dynamic light scattering, atomic force microscopy, and quartz crystal microbalance with dissipation (QCM-D). Here, poly(diallydimethylammonium chloride) (PDDA) was used to promote the attachment of iron oxide nanoparticles (IONPs) onto the silica surface to assemble a nanocomposite with magnetic and catalytic bifunctionality. High molecular weight PDDA tended to adsorb on silica colloid, forming a more extended conformation layer than low molecular weight PDDA. Subsequent attachment of IONPs onto this extended PDDA layer was more randomly distributed, forming isolated islands with open space between them. By taking amoxicillin, an antibiotic commonly found in pharmaceutical waste, as the model system, better removal was observed for silica-iron oxide nanocomposite with a more extended open shell structure.

MeSH terms: Quaternary Ammonium Compounds/chemistry; Amoxicillin/isolation & purification; Anti-Bacterial Agents/isolation & purification; Ferric Compounds/chemistry*; Light; Molecular Weight; Osmolar Concentration; Polyethylenes/chemistry; Scattering, Radiation; Silicon Dioxide/chemistry*; Microscopy, Atomic Force; Nanocomposites/chemistry*; Static Electricity; Hydrodynamics; Quartz Crystal Microbalance Techniques
Design and develop a video conferencing framework for real-time telemedicine applications using secure group-based communication architecture

Mat Kiah ML, Al-Bakri SH, Zaidan AA, Zaidan BB, Hussain M

J Med Syst, 2014 Oct;38(10):133.
PMID: 25199651 DOI: 10.1007/s10916-014-0133-y

One of the applications of modern technology in telemedicine is video conferencing. An alternative to traveling to attend a conference or meeting, video conferencing is becoming increasingly popular among hospitals. By using this technology, doctors can help patients who are unable to physically visit hospitals. Video conferencing particularly benefits patients from rural areas, where good doctors are not always available. Telemedicine has proven to be a blessing to patients who have no access to the best treatment. A telemedicine system consists of customized hardware and software at two locations, namely, at the patient's and the doctor's end. In such cases, the video streams of the conferencing parties may contain highly sensitive information. Thus, real-time data security is one of the most important requirements when designing video conferencing systems. This study proposes a secure framework for video conferencing systems and a complete management solution for secure video conferencing groups. Java Media Framework Application Programming Interface classes are used to design and test the proposed secure framework. Real-time Transport Protocol over User Datagram Protocol is used to transmit the encrypted audio and video streams, and RSA and AES algorithms are used to provide the required security services. Results show that the encryption algorithm insignificantly increases the video conferencing computation time.

MeSH terms: Computer Systems*; Confidentiality; Programming Languages; Software; Computer Security*; Telemedicine/methods*; Videoconferencing*
Insecticidal activity and expression of cytochrome P450 family 4 genes in Aedes albopictus after exposure to pyrethroid mosquito coils

Avicor SW, Wajidi MF, El-Garj FM, Jaal Z, Yahaya ZS

Protein J, 2014 Oct;33(5):457-64.
PMID: 25199940 DOI: 10.1007/s10930-014-9580-z

Mosquito coils are insecticides commonly used for protection against mosquitoes due to their toxic effects on mosquito populations. These effects on mosquitoes could induce the expression of metabolic enzymes in exposed populations as a counteractive measure. Cytochrome P450 family 4 (CYP4) are metabolic enzymes associated with a wide range of biological activities including insecticide resistance. In this study, the efficacies of three commercial mosquito coils with different pyrethroid active ingredients were assessed and their potential to induce the expression of CYP4 genes in Aedes albopictus analyzed by real-time quantitative PCR. Coils containing 0.3 % D-allethrin and 0.005 % metofluthrin exacted profound toxic effects on Ae. albopictus, inducing high mortalities (≥90 %) compared to the 0.2 % D-allethrin reference coil. CYP4H42 and CYP4H43 expressions were significantly higher in 0.3 % D-allethrin treated mosquitoes compared to the other treated populations. Short-term (KT50) exposure to mosquito coils induced significantly higher expression of both genes in 0.005 % metofluthrin exposed mosquitoes. These results suggest the evaluated products provided better protection than the reference coil; however, they also induced the expression of metabolic genes which could impact negatively on personal protection against mosquito.

MeSH terms: Aedes/drug effects*; Aedes/enzymology; Aedes/genetics; Allethrin/pharmacology*; Animals; Cytochrome P-450 Enzyme System/genetics; Cytochrome P-450 Enzyme System/metabolism*; Female; Insecticides/pharmacology*; Gene Expression/drug effects; Polymerase Chain Reaction
Fulltext Lateral flow test using Echinococcus granulosus native antigen B and comparison of IgG and IgG4 dipsticks for detection of human cystic echinococcosis

Khalilpour A, Sadjjadi SM, Moghadam ZK, Yunus MH, Zakaria ND, Osman S, et al.

Am J Trop Med Hyg, 2014 Nov;91(5):994-9.
PMID: 25200268 DOI: 10.4269/ajtmh.14-0170

Cystic echinococcosis (CE) caused by infection with Echinococcus granulosus is of major concern for humans in many parts of the world. Antigen B was prepared from E. granulosus hydatid fluid, and Western blots confirmed eight batches showing a band corresponding to the 8-/12-kDa subunit with positive serum and no low-molecular mass band (< 15 kDa) with negative serum. The batches were pooled and used to prepare lateral flow immunoglobulin G4 (IgG4) and IgG dipsticks. Diagnostic sensitivity was determined using serum samples from 21 hydatidosis patients, and diagnostic specificity was established using sera from 17 individuals infected with other parasites and 15 healthy people. IgG4 dipstick had a diagnostic sensitivity of 95% (20 of 21) and a specificity of 100% (32 of 32). The IgG dipstick had a sensitivity of 100% (21 of 21) and a specificity of 87.5% (28 of 32). Thus, both IgG and IgG4 dipsticks had high sensitivities, but IgG4 had greater specificity for the diagnosis of human CE.

MeSH terms: Animals; Antibodies, Helminth/blood; Antibodies, Helminth/immunology; Antigens, Helminth/blood; Antigens, Helminth/immunology; Echinococcosis/diagnosis*; Echinococcosis/immunology*; Electrophoresis, Polyacrylamide Gel; Gold; Humans; Immunoglobulin G/blood; Immunoglobulin G/immunology; Lipoproteins/blood; Lipoproteins/immunology*; Sensitivity and Specificity; Echinococcus granulosus/immunology*; Metal Nanoparticles/chemistry
Fulltext Peginterferon alfa-2b in the treatment of Chinese patients with HBeAg-positive chronic hepatitis B: a randomized trial

Cheng J, Wang Y, Hou J, Luo D, Xie Q, Ning Q, et al.

J Clin Virol, 2014 Dec;61(4):509-16.
PMID: 25200354 DOI: 10.1016/j.jcv.2014.08.008

In mainland China, peginterferon (PEG-IFN) alfa-2b 1.0μg/kg/wk for 24 weeks is the approved treatment for HBeAg-positive chronic hepatitis B.

MeSH terms: Adolescent; Adult; Alanine Transaminase/blood; Antiviral Agents/adverse effects; Antiviral Agents/therapeutic use*; DNA, Viral/blood; Female; Hepatitis B e Antigens/blood*; Humans; Male; Middle Aged; Polyethylene Glycols/adverse effects; Polyethylene Glycols/therapeutic use*; Recombinant Proteins/adverse effects; Recombinant Proteins/therapeutic use; Treatment Outcome; Interferon-alpha/adverse effects; Interferon-alpha/therapeutic use*; Hepatitis B, Chronic/drug therapy*; Asian Continental Ancestry Group; Young Adult
Tuberculosis (TB)-associated immune reconstitution inflammatory syndrome in TB-HIV co-infected patients in Malaysia: prevalence, risk factors, and treatment outcomes

Tan HY, Yong YK, Lim SH, Ponnampalavanar S, Omar SF, Pang YK, et al.

Sex Health, 2014 Dec;11(6):532-9.
PMID: 25200957 DOI: 10.1071/SH14093

Background Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is an important early complication of antiretroviral therapy (ART) in countries with high rates of endemic TB, but data from South-East Asia are incomplete. Identification of prevalence, risk factors and treatment outcomes of TB-IRIS in Malaysia was sought.
METHODS: A 3-year retrospective study was conducted among TB-HIV co-infected patients treated at the University of Malaya Medical Centre. Simple and adjusted logistic regressions were used to identify the predictors for TB-IRIS while Cox regression was used to assess the influence of TB-IRIS on long-term CD4 T-cell recovery.
RESULTS: One hundred and fifty-three TB-HIV patients were enrolled, of whom 106 had received both anti-TB treatment (ATT) and ART. The median (IQR) baseline CD4 T-cell count was 52 cells μL(-1) (13-130 cells μL(-1)). Nine of 96 patients (9.4%) developed paradoxical TB-IRIS and eight developed unmasking TB-IRIS, at a median (IQR) time of 27 (12-64) and 19 (14-65) days, respectively. In adjusted logistic regression analysis, only disseminated TB was predictive of TB-IRIS [OR: 10.7 (95% CI: 1.2-94.3), P=0.032]. Mortality rates were similar for TB-IRIS (n=1, 5.9%) and non-TB-IRIS (n=5, 5.7%) patients and CD4 T-cell recovery post-ART was not different between the two groups (P=0.363).
CONCLUSION: Disseminated TB was a strong independent predictor of TB-IRIS in Malaysian HIV-TB patients after commencing ART. This finding underscores the role of a high pathogen load in the pathogenesis of TB-IRIS; so interventions that reduce pathogen load before ART may benefit HIV patients with disseminated TB.
Sexuality and the drive for muscularity: evidence of associations among British men

Swami V, Diwell R, McCreary DR

Body Image, 2014 Sep;11(4):543-6.
PMID: 25201097 DOI: 10.1016/j.bodyim.2014.08.008

Previous studies have documented associations between sexuality and body image, but the directionality of this association is unclear among men. This study examined whether men's drive for muscularity can be considered a correlate of their sexuality. A community-based sample of 292 heterosexual men from London, UK, completed a survey consisting of measures of drive for muscularity, sociosexuality, sexual assertiveness, sexual esteem, and sexual sensation seeking. A multiple regression analysis showed that greater drive for muscularity was predicted by more unrestricted sociosexuality (i.e., a greater proclivity for short-term, transient relationships), greater sexual sensation seeking, and greater sexual assertiveness, once the effects of participant age and body mass index had been accounted for. Possible avenues for intervention based on a sex-positive approach are discussed in conclusion.

MeSH terms: Adolescent; Adult; Body Image/psychology*; Drive*; Humans; London; Male; Men/psychology; Middle Aged; Personal Satisfaction; Surveys and Questionnaires; Self Concept*; Sexual Behavior/psychology*; Sexual Behavior/statistics & numerical data; Body Mass Index; Heterosexuality/psychology; Muscle Strength*; Young Adult
Prevalence, characterization and antibiotic resistance of Pasteurella multocida isolated from bovine respiratory infection

Jamali H, Rezagholipour M, Fallah S, Dadrasnia A, Chelliah S, Velappan RD, et al.

Vet J, 2014 Nov;202(2):381-3.
PMID: 25201254 DOI: 10.1016/j.tvjl.2014.07.024

The objectives of this study were to determine the prevalence, characterization and antibiotic resistance of Pasteurella multocida isolated from calves with respiratory infection in Iran. P. multocida was detected in 141/169 bovine respiratory infection cases on Iranian dairy and beef farms. P. multocida were grouped into serogroups A (126/141), D (12/141), and B (3/141). Of the P. multocida isolates, all harboured the psl, ompH, oma87, fimA, ptfA, nanB, and nanH genes, 139/141 had hsf-2, and 115/141 pfhA, and tadD. The isolates were most frequently resistant to penicillin G (43/141 resistant isolates; 30.5%) and streptomycin (31/141; 22%).

MeSH terms: Animals; Cattle; Cattle Diseases/microbiology*; Cattle Diseases/epidemiology*; Iran/epidemiology; Pasteurella Infections/microbiology; Pasteurella Infections/epidemiology; Pasteurella Infections/veterinary*; Respiratory Tract Infections/microbiology; Respiratory Tract Infections/epidemiology; Respiratory Tract Infections/veterinary*; Serotyping/veterinary; Prevalence; Seroepidemiologic Studies; Polymerase Chain Reaction/veterinary; Pasteurella multocida/drug effects*; Pasteurella multocida/genetics; Pasteurella multocida/pathogenicity; Pasteurella multocida/physiology*; Drug Resistance, Bacterial*
Enhancing the various solvent extraction method via microwave irradiation for extraction of lipids from marine microalgae in biodiesel production

Teo CL, Idris A

Bioresour Technol, 2014 Nov;171:477-81.
PMID: 25201293 DOI: 10.1016/j.biortech.2014.08.024

The types of microalgae strains and the method used in lipid extraction have become crucial factors which influence the productivity of crude oil. In this paper, Nannochloropsis sp. and Tetraselmis sp. were chosen as the strains and four different methods were used to extract the lipids: Hara and Radin, Folch, Chen and Bligh and Dyer. These methods were performed by using conventional heating and microwave irradiation methods. Results revealed that highest lipid yield from the different species was obtained using different extraction methods; both under microwave irradiation. The lipid yield for Tetraselmis sp. and Nannochloropsis sp. was highest when Hara and Radin (8.19%), and Folch (8.47%) methods were used respectively under microwave irradiation. The lipids extracted were then transesterified to biodiesel and the quality of the biodiesel was analyzed using the gas chromatography.

MeSH terms: Chlorophyta/chemistry*; Chromatography, Gas; Lipids/analysis; Lipids/isolation & purification*; Microwaves*; Solvents/chemistry; Biofuels*; Stramenopiles/chemistry*; Microalgae/chemistry*; Liquid-Liquid Extraction/methods*
A case of iatrogenic Cushing syndrome and apparent mineralocorticoid excess presenting with accelerated hypertension and proteinuria

Kong WY, Leedman P, Irish A

Intern Med J, 2014 Sep;44(9):932-4.
PMID: 25201428 DOI: 10.1111/imj.12022
MeSH terms: Cushing Syndrome/chemically induced*; Female; Humans; Hypertension/chemically induced*; Iatrogenic Disease*; Middle Aged; Proteinuria/chemically induced*; Treatment Outcome; Medroxyprogesterone Acetate/administration & dosage; Medroxyprogesterone Acetate/adverse effects*; Antineoplastic Agents, Hormonal/administration & dosage; Antineoplastic Agents, Hormonal/adverse effects*; Mineralocorticoid Excess Syndrome, Apparent/chemically induced*
Fulltext Accuracy of a digital weight scale relative to the nintendo wii in measuring limb load asymmetry

Kumar NS, Omar B, Joseph LH, Hamdan N, Htwe O, Hamidun N

J Phys Ther Sci, 2014 Aug;26(8):1205-7.
PMID: 25202181 DOI: 10.1589/jpts.26.1205

[Purpose] The aim of the present study was to investigate the accuracy of a digital weight scale relative to the Wii in limb loading measurement during static standing. [Methods] This was a cross-sectional study conducted at a public university teaching hospital. The sample consisted of 24 participants (12 with osteoarthritis and 12 healthy) recruited through convenient sampling. Limb loading measurements were obtained using a digital weight scale and the Nintendo Wii in static standing with three trials under an eyes-open condition. The limb load asymmetry was computed as the symmetry index. [Results] The accuracy of measurement with the digital weight scale relative to the Nintendo Wii was analyzed using the receiver operating characteristic (ROC) curve and Kolmogorov-Smirnov test (K-S test). The area under the ROC curve was found to be 0.67. Logistic regression confirmed the validity of digital weight scale relative to the Nintendo Wii. The D statistics value from the K-S test was found to be 0.16, which confirmed that there was no significant difference in measurement between the equipment. [Conclusion] The digital weight scale is an accurate tool for measuring limb load asymmetry. The low price, easy availability, and maneuverability make it a good potential tool in clinical settings for measuring limb load asymmetry.
Fulltext Development of microsatellites in Labisia pumila (Myrsinaceae), an economically important Malaysian herb

Tnah LH, Lee CT, Lee SL, Ng CH, Ng KK

Appl Plant Sci, 2014 Jun;2(6).
PMID: 25202631 DOI: 10.3732/apps.1400019
Fulltext Cerebral CT angiography and CT perfusion in acute stroke detection: a systematic review of diagnostic value

Sabarudin A, Subramaniam C, Sun Z

Quant Imaging Med Surg, 2014 Aug;4(4):282-90.
PMID: 25202664 DOI: 10.3978/j.issn.2223-4292.2014.07.10

The purpose of this study was to analyse the diagnostic value of cerebral CT angiography (CTA) and CT perfusion (CTP) examinations in the detection of acute stroke based on a systematic review of the current literature. The review was conducted based on searching of seven databases for articles published between 1993 and 2013. Diagnostic value in terms of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy was analysed from 21 articles which were found to meet selection criteria. The mean sensitivity, specificity, PPV, NPV and accuracy for CTA were significantly higher than those for CTP with 83.2% (95% CI: 57.9-100.0%), 95.0% (95% CI: 74.4-100%), 84.1% (95% CI: 50.0-100%), 97.1 (95% CI: 94.0-100%) and 94.0% (95% CI: 83.0-99.0) versus 69.9% (95% CI: 20.0-97.0%), 87.4 (95% CI: 61.0-100.0%), 76.4% (95% CI: 48.0-95.4%), 78.2% (95% CI: 55.8-93.9%) and 89.8% (95% CI: 75.7-97.1%), respectively. This analysis shows that CTA has high diagnostic value in detecting high degree of cerebral arterial stenosis (>70%) whereas CTP provides high specificity in the detection of ischemia and infarct tissue of brain.

MeSH terms: Brain; Cerebral Angiography; Constriction, Pathologic; Cytidine Triphosphate; Infarction; Sensitivity and Specificity; Tomography, X-Ray Computed; Patient Selection; Stroke; Computed Tomography Angiography
Fulltext Oscillations for neutral functional differential equations

Ahmed FN, Ahmad RR, Din UK, Noorani MS

ScientificWorldJournal, 2014;2014:124310.
PMID: 25202713 DOI: 10.1155/2014/124310

We will consider a class of neutral functional differential equations. Some infinite integral conditions for the oscillation of all solutions are derived. Our results extend and improve some of the previous results in the literature.

MeSH terms: Algorithms*; Models, Theoretical*
Fulltext A comprehensive propagation prediction model comprising microfacet based scattering and probability based coverage optimization algorithm

Kausar AS, Reza AW, Wo LC, Ramiah H

ScientificWorldJournal, 2014;2014:601729.
PMID: 25202733 DOI: 10.1155/2014/601729

Although ray tracing based propagation prediction models are popular for indoor radio wave propagation characterization, most of them do not provide an integrated approach for achieving the goal of optimum coverage, which is a key part in designing wireless network. In this paper, an accelerated technique of three-dimensional ray tracing is presented, where rough surface scattering is included for making a more accurate ray tracing technique. Here, the rough surface scattering is represented by microfacets, for which it becomes possible to compute the scattering field in all possible directions. New optimization techniques, like dual quadrant skipping (DQS) and closest object finder (COF), are implemented for fast characterization of wireless communications and making the ray tracing technique more efficient. In conjunction with the ray tracing technique, probability based coverage optimization algorithm is accumulated with the ray tracing technique to make a compact solution for indoor propagation prediction. The proposed technique decreases the ray tracing time by omitting the unnecessary objects for ray tracing using the DQS technique and by decreasing the ray-object intersection time using the COF technique. On the other hand, the coverage optimization algorithm is based on probability theory, which finds out the minimum number of transmitters and their corresponding positions in order to achieve optimal indoor wireless coverage. Both of the space and time complexities of the proposed algorithm surpass the existing algorithms. For the verification of the proposed ray tracing technique and coverage algorithm, detailed simulation results for different scattering factors, different antenna types, and different operating frequencies are presented. Furthermore, the proposed technique is verified by the experimental results.

MeSH terms: Algorithms*; Models, Theoretical*

External Links