Browse publications by year: 2018

  1. Fulltext Grandparents - Grandchildren Relationship in Iran, 2017
    Momtaz YA, Vidouje MM, Foroughan M, Sahaf R, Laripour R
    Clin Pract Epidemiol Ment Health, 2018;14:296-303.
    PMID: 30972129 DOI: 10.2174/1745017901814010296
    Introduction: With the continuing growth of aged populations, it is imperative to find ways to maintain and improve the quality of life in old age. It has been documented that grandparents-grandchildren relationship is significantly contributed to quality of life of older adults. This study was conducted to identify the status and associated factors of grandparents-grandchildren relationship in a sample of Iran.

    Methods: This cross-sectional study was conducted on 377 community dwelling older adults 60 years and over living in Kashan, Iran. A multistage proportional random sampling technique was applied to obtain the sample. The grandparent -grandchildren relationship was measured by a researcher-developed 16-item scale. The data were analyzed using SPSS version 23 and AMOS 23.

    Results: The mean age of the respondents was 70.42(SD = 8.20) years. About 62% of the respondents were female and 60.7% were married. The average score of grandparents-grandchild relationship was 67.60(SD = 12.47). The multiple linear regression analysis revealed a significant model (F (11, 365) = 19.05, P < 0.001), where information communication technology of grandparents, geographical distance between grandparents and grandchildren, and the quality of relationship between grandparents and parents of grandchildren were the most important predictors of the grandparents-grandchildren relationship.

    Conclusion: The findings from the current study showed that status of grandparents-grandchildren relationship is moderate to high and influenced by some factors. It is, therefore, suggested that policymakers pay more attention to strengthening grandparent-grandchild relationship by providing educational programs for families and encouraging the elderly to learn and use information communication technology.

    MeSH terms: Grandparents; Adult; Aged; Attention; Communication; Cross-Sectional Studies; Family; Female; Humans; Iran; Marriage; Parents; Quality of Life; Surveys and Questionnaires; Regression Analysis; Independent Living
  2. Fulltext Perception towards the preparedness for disaster management among nurses in community clinics
    Fatimah Sham, Lailatul Hazzliza Musa, Nor Marini Mohamed, Norjah Othman
    Scientific Research Journal, 2018;15(2):67-79.
    MyJurnal
    Disasters are defined as extraordinary events which occur abruptly, bringing great damage or harm, loss, and destruction to people and the environment. Nurses may have a more conflict and difficulties in disaster decision making where the victim condition need to be treated in disaster place. Nurses play a key role in hospital as a leaders and managers in the disaster operation and command center but limited data shows that the nurses experience in disaster management. The aim of this study is to evaluate the perception of knowledge and skills on the preparedness in disaster management among nurses in community clinics. A descriptive cross-sectional study was conducted in 27 government clinics in one of the states in Malaysia with a convenient sampling, 260 participants are selected. The questionnaire consisted of three sections; socio-demographic characteristics, the perception of knowledge and skill towards preparedness for disaster management rated on a Likert scale. In the effort to collect the intended data, a self-report questionnaire adapted and modified from Disaster Preparedness Evaluation Tool (DPET) was implemented (Alrazeeni, 2015). This study revealed that Nurses in these community clinics were moderate in terms of the perception of knowledge (Mean= 3.65, SD= 0.61) and the perceived skills (Mean= 3.68, SD= 0.56) on the preparedness in Disaster Management. Nevertheless, they were interested in disaster preparedness management training (n=227, 87.3%) and were confident as first responders of disaster (Mean= 3.88, SD= 0.61). However, they were not much involved in disaster preparedness plan (Mean= 3.23, SD= 0.90) and claimed that there was a lack of leadership figure in disaster situation (Mean= 3.06, SD= 0.92). In conclusion, nurses in community clinics need to gain knowledge and skills by involving themselves in disaster planning and drills as the preparation for disaster management for them to be the first responders in helping and managing people in this situation.
    MeSH terms: Cross-Sectional Studies; Decision Making; Demography; Disaster Planning; Disasters; Government; Leadership; Malaysia; Surveys and Questionnaires; Self Report
  3. Fulltext Knowledge and attitude of teachers in selected Malaysian primary school towards dental injuries
    Syazwani Hassan, Nur Nabila Zulkifly, Venkiteswaran, Annapurny, Rohaida Abdul Halim
    Scientific Research Journal, 2018;15(2):51-66.
    MyJurnal
    To ascertain the level of knowledge among primary school teachers towards the management of traumatic dental injuries (TDIs) in school and to determine the preference among teachers regarding the education tools that can be used to increase awareness and knowledge among them. A total of 150 teachers from primary schools in three different districts were included in the study and they were given self-administered questionnaires to be filled. The validated questionnaire was distributed randomly in the selected schools. The questionnaire included two scenarios comprising of tooth fracture and avulsion. Questions regarding awareness and management of these scenarios were asked. All 150 participants answered the questionnaire; of these 74% were females 26% were males. 64% of the participants had received tertiary education. Although 70% of teachers had obtained first aid training, only 9.3% of them had received training regrading dental injuries. About 53% of participants knew the correct answer for the appropriate response to fractured tooth and only 35.3% managed to correctly answer the question related to appropriate response to an avulsed tooth. Only 38.7% knew about appropriate rinsing solution and a mere 4.7% were familiar with proper storage media. Even though the teachers have poor knowledge regarding management of dental injuries, it is reassuring to know that 93% of them are keen on further training and awareness. More educational programmes need to be introduced to empower the teachers with the relevant knowledge required to deal with dental emergencies.
    MeSH terms: Emergencies; Female; First Aid; Male; Surveys and Questionnaires; Schools; Tooth Fractures; Tooth Avulsion; School Teachers
  4. Fulltext Effects of papaya leaves crude extract on the physicochemical and sensory characteristics of marinated chicken meat
    Normah Ismail, Rosliana Rosman
    Scientific Research Journal, 2018;15(2):35-50.
    MyJurnal
    The purpose of this study was to investigate the effect of papaya leaves crude extract on the physicochemical properties of marinated chicken meat. Papaya leaves was extracted with sodium acetate (CH3COONa) buffer (pH 7.2) at room temperature. Protein concentration and activity of enzyme in the crude extract were determined by using UV-Spectrophotometer. The crude extract was mixed with marinated ingredients and then coated onto chicken meat which was subsequently kept for overnight in refrigerator at chill temperature. Protein concentration of the enzyme was identified as 166.36 μg/μl and enzyme activity was 1.28 CDU/ml. Results also showed that lightness (L*), cooking loss and shrinkage of the marinated chicken were higher than control. Redness (a*), yellowness (b*), protein content, water-holding capacity, shear force, and texture profile analysis were lower than control. Microstructure analysis showed that the chicken meat muscle was destructed in the presence of papaya crude extract. Sensory acceptability evaluation of marinated chicken which was carried out by using 9 point hedonic scale suggested that chicken meat treated with papaya crude extract gave significant effect on texture, juiciness, flavour and overall acceptability compared to commercial bromelain. Additionally, the use of papaya crude extract gave a significant effect on the physicochemical properties of marinated chicken.
  5. Fulltext Conceptualising the benefit framework of an enterprise content management system (ECMS)
    Mohamad Rahimi Mohamad Rosman, Mohammad Azhan Abdul Aziz
    Scientific Research Journal, 2018;15(2):17-34.
    MyJurnal
    Content management is an organisational effort of managing content, particularly in digital format. Although it has been over 25 years since content management was introduced, this field of study is still considered an emerging topic with unresolved issues-in particular, the subject of benefit achievement. Therefore, grounded on an extensive review of 135 articles, the purpose of this study is to investigate the benefits that organisations can gain through the proper use of an Enterprise Content Management System (ECMS). Subsequently, this paper identifies a list of ECMS benefits and proposes an ECMS benefit framework for further exploration into this field. Our result shows that although ECMS does bring benefits to organisations, these benefits are diverse; indicating that there are certain determinants or factors influencing the achievement of such benefits. Moreover, it is also found that in the context of the benefit framework of Shang and Seddon [10], three categories were found relevant to the field of content management: operational benefit, managerial benefit, and strategic benefit.
    MeSH terms: Organizations; Physical Examination
  6. Fulltext Optimization of Mechanical Properties for Polyoxymethylene/Glass Fiber/Polytetrafluoroethylene Composites Using Response Surface Methodology
    Kunnan Singh JS, Ching YC, Abdullah LC, Ching KY, Razali S, Gan SN
    Polymers (Basel), 2018 Mar 20;10(3).
    PMID: 30966373 DOI: 10.3390/polym10030338
    This paper investigated the effects of polytetrafluoroethylene (PTFE) micro-particles on mechanical properties of polyoxymethylene (POM) composites. Since PTFE is immiscible with most polymers, the surface was etched using sodium naphthalene salt in tetrahydrofuran to increase its surface energy. The effects of two variables, namely PTFE content and PTFE etch time, on the mechanical properties of the composite were studied. Experiments were designed in accordance to response surface methodology (RSM) using central composite design (CCD). Samples were prepared with different compositions of PTFE (1.7, 4.0, 9.5, 15.0, or 17.3 wt %) at different PTFE etch times (2.9, 5.0, 10.0, 15.0, or 17.1 min). Four mechanical properties of the POM/GF/PTFE composites, that is, strength, stiffness, toughness, and hardness, were characterized as a function of two studied variables. The dependency of these mechanical properties on the PTFE etch conditions was analyzed using analysis of variance (ANOVA). Overall desirability, D global index, was computed based on the combination of these mechanical properties for POM/GF/PTFE composites. The D global index was found to be 87.5%, when PTFE content and PTFE etch time were 6.5% and 10 min, respectively. Good correlation between experimental and RSM models was obtained using normal probability plots.
  7. Fulltext Polyhexamethylene Biguanide and Nadifloxacin Self-Assembled Nanoparticles: Antimicrobial Effects against Intracellular Methicillin-Resistant Staphylococcus aureus
    Kamaruzzaman NF, Pina MF, Chivu A, Good L
    Polymers (Basel), 2018 May 12;10(5).
    PMID: 30966555 DOI: 10.3390/polym10050521
    The treatment of skin and soft tissue infections caused by methicillin-resistant Staphylococcus aureus (MRSA) remains a challenge, partly due to localization of the bacteria inside the host's cells, where antimicrobial penetration and efficacy is limited. We formulated the cationic polymer polyhexamethylene biguanide (PHMB) with the topical antibiotic nadifloxacin and tested the activities against intracellular MRSA in infected keratinocytes. The PHMB/nadifloxacin nanoparticles displayed a size of 291.3 ± 89.6 nm, polydispersity index of 0.35 ± 0.04, zeta potential of +20.2 ± 4.8 mV, and drug encapsulation efficiency of 58.25 ± 3.4%. The nanoparticles killed intracellular MRSA, and relative to free polymer or drugs used separately or together, the nanoparticles displayed reduced toxicity and improved host cell recovery. Together, these findings show that PHMB/nadifloxacin nanoparticles are effective against intracellular bacteria and could be further developed for the treatment of skin and soft tissue infections.
    MeSH terms: Anti-Infective Agents; Anti-Bacterial Agents; Biguanides; Methicillin; Polymers; Quinolizines; Keratinocytes; Soft Tissue Infections; Fluoroquinolones; Nanoparticles; Methicillin-Resistant Staphylococcus aureus
  8. Fulltext An insight of linear regression analysis
    Ng, Set Foong, Chew, Yee Ming, Chng, Pei Eng, Ng, Kok Shien
    Scientific Research Journal, 2018;15(2):1-16.
    MyJurnal
    Regression models are developed in various field of applications to help researchers to predict certain variables based on other predictor variables. The dependent variables in the regression model are estimated by a number of independent variables. Model utility test is a hypothesis testing procedure in regression to verify if there is a useful relationship between the dependent variable and the independent variable. The hypothesis testing procedure that involves p-value is commonly used in model utility test. A new technique that involves coefficient of determination R2 in model utility test is developed in this paper. The effectiveness of the model utility test in testing the significance of regression model is evaluated using simple linear regression model with the significance level α = 0.01, 0.025 and 0.05. The study in this paper shows that a regression model that is declared to be a significant model by using model utility test, however it fails to guarantee a strong linear relationship between the independent variable and dependent variable. Based on the evaluation presented in this paper, it is shown that the p-value approach in model utility test is not a good technique in evaluating the significance of a regression model. The results of this study could serve as a reference for other researchers applying regression analysis in their studies.
  9. Fulltext Search for new physics in dijet angular distributions using proton-proton collisions at s = 13 TeV and constraints on dark matter and other models
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2018;78(9):789.
    PMID: 30956565 DOI: 10.1140/epjc/s10052-018-6242-x
    A search is presented for physics beyond the standard model, based on measurements of dijet angular distributions in proton-proton collisions at s = 13 TeV . The data collected with the CMS detector at the LHC correspond to an integrated luminosity of 35.9 fb - 1 . The observed distributions, corrected to particle level, are found to be in agreement with predictions from perturbative quantum chromodynamics that include electroweak corrections. Constraints are placed on models containing quark contact interactions, extra spatial dimensions, quantum black holes, or dark matter, using the detector-level distributions. In a benchmark model where only left-handed quarks participate, contact interactions are excluded at the 95% confidence level up to a scale of 12.8 or 17.5TeV, for destructive or constructive interference, respectively. The most stringent lower limits to date are set on the ultraviolet cutoff in the Arkani-Hamed-Dimopoulos-Dvali model of extra dimensions. In the Giudice-Rattazzi-Wells convention, the cutoff scale is excluded up to 10.1TeV. The production of quantum black holes is excluded for masses below 5.9 and 8.2TeV, depending on the model. For the first time, lower limits between 2.0 and 4.6TeVare set on the mass of a dark matter mediator for (axial-)vector mediators, for the universal quark coupling g q = 1.0 .
  10. Fulltext Bacteriostatic Activity of LLDPE Nanocomposite Embedded with Sol⁻Gel Synthesized TiO₂/ZnO Coupled Oxides at Various Ratios
    Saharudin KA, Sreekantan S, Basiron N, Khor YL, Harun NH, S M N Mydin RB, et al.
    Polymers (Basel), 2018 Aug 06;10(8).
    PMID: 30960803 DOI: 10.3390/polym10080878
    Metal oxide-polymer nanocomposite has been proven to have selective bactericidal effects against the main and common pathogens (Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli)) that can cause harmful infectious diseases. As such, this study looked into the prospect of using TiO₂/ZnO with linear low-density polyethylene (LLDPE) to inactivate S. aureus and E. coli. The physical, structural, chemical, mechanical, and antibacterial properties of the nanocomposite were investigated in detail in this paper. The production of reactive species, such as hydroxyl radicals (•OH), holes (h⁺), superoxide anion radicals (O₂•¯), and zinc ion (Zn2+), released from the nanocomposite were quantified to elucidate the underlying antibacterial mechanisms. LLDPE/25T75Z with TiO₂/ZnO (1:3) nanocomposite displayed the best performance that inactivated S. aureus and E. coli by 95% and 100%, respectively. The dominant reactive active species and the zinc ion release toward the superior antibacterial effect of nanocomposite are discussed. This work does not only offer depiction of the effective element required for antimicrobial biomedical appliances, but also the essential structural characteristics to enhance water uptake to expedite photocatalytic activity of LLDPE/metal oxide nanocomposite for long term application.
  11. Fulltext Friction Performance of Aged T-BFRP Composite for Bearing Applications
    Nirmal U
    Polymers (Basel), 2018 Sep 25;10(10).
    PMID: 30960991 DOI: 10.3390/polym10101066
    The current work is an attempt to reduce friction coefficient of the treated betelnut fibre reinforced polyester (T-BFRP) composites by aging them in twelve different solutions with different kinematic viscosities. The test will be performed on a pin on disc (POD) wear test rig using different applied loads (5⁻30 N), different sliding distances (0⁻6.72 km) at sliding speed of 2.8 m/s subjected to a smooth stainless steel counterface (AISI-304). Different orientations of the fibre mats such as anti-parallel (AP) and parallel (P) orientations subjected to the rotating counterface will be considered. The worn surfaces were examined through optical microscopy imaging and it was found that the aged specimens had significantly lower damages as compared to neat polyester (NP) and the unaged samples. Besides, P-O samples revealed lower friction coefficients as compared to AP-O, i.e., reduction was about 24.71%. Interestingly, aging solutions with lower kinematic viscosities revealed lower friction coefficients of the aged T-BFRP composites when compared to the ones aged in higher kinematic viscosities.
    MeSH terms: Areca; Biomechanical Phenomena; Dietary Fiber; Microscopy; Polyesters; Stainless Steel; Viscosity; Friction; Laxatives
  12. Fulltext Enhancement of Plasticizing Effect on Bio-Based Polyurethane Acrylate Solid Polymer Electrolyte and Its Properties
    Tuan Naiwi TSR, Aung MM, Ahmad A, Rayung M, Su'ait MS, Yusof NA, et al.
    Polymers (Basel), 2018 Oct 12;10(10).
    PMID: 30961067 DOI: 10.3390/polym10101142
    Polyurethane acrylate (PUA) from vegetable oil has been synthesized and prepared for solid polymer electrolyte. Polyol has been end-capped with Toluene 2,4-Diisocyanate (TDI) followed by hydroxylethylmethylacrylate (HEMA) in a urethanation process to produce PUA. The mixtures were cured to make thin polymeric films under UV radiation to produce excellent cured films which exhibit good thermal stability and obtain high ionic conductivity value. 3 to 15 wt. % of ethylene carbonate (EC) mixed with 25 wt. % LiClO₄ was added to PUA to obtain PUA electrolyte systems. PUA modified with plasticizer EC 9 wt. % achieved the highest conductivity of 7.86 × 10-4 S/cm, and relatively improved the linear sweep voltammetry, transference number and dielectric properties. Fourier Transform Infrared Spectroscopy (FTIR) and dielectric analysis were presented. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), followed by X-ray Diffraction (XRD) and morphology have been studied. The addition of plasticizer to the polyurethane acrylate shows significant improvement in terms of the conductivity and performance of the polymer electrolyte.
  13. Fulltext Effect of Modified Tapioca Starch on Mechanical, Thermal, and Morphological Properties of PBS Blends for Food Packaging
    Ayu RS, Khalina A, Harmaen AS, Zaman K, Jawaid M, Lee CH
    Polymers (Basel), 2018 Oct 25;10(11).
    PMID: 30961112 DOI: 10.3390/polym10111187
    In this study, polybutylene succinate (PBS) was blended with five types of modified tapioca starch to investigate the effect of modified tapioca starch in PBS blends for food packaging by identifying its properties. Tensile and flexural properties of blends found deteriorated for insertion of starch. This is due to poor interface, higher void contents and hydrolytic degradation of hydrophilic starch. FTIR results show all starch/PBS blends are found with footprints of starch except OH stretching vibration which is absent in B40 blends. Besides, Broad O⁻H absorption in all specimens show that these are hydrogen bonded molecules and no free O⁻H bonding was found. SEM testing shows good interfacial bonding between PBS and starch except E40 blends. Therefore, poor results of E40 blends was expected. In TGA, a slightly weight loss found between 80 to 100 °C due to free water removal. Apart from this, insertion of all types of starch reduces thermal stability of blend. However, high crystallinity of starch/PBS blend observed better thermal stability but lower char yield. Starch A and B blends are suggested to be used as food wrap and food container materials while starch D blend is suitable for grocery plastic bags according to observed results.
  14. Fulltext Preparation and Characterization of Low-Molecular-Weight Natural Rubber Latex via Photodegradation Catalyzed by Nano TiO₂
    Ibrahim S, Othman N, Sreekantan S, Tan KS, Mohd Nor Z, Ismail H
    Polymers (Basel), 2018 Nov 01;10(11).
    PMID: 30961141 DOI: 10.3390/polym10111216
    Natural rubber is one of the most important renewable biopolymers used in many applications due to its special properties that cannot be easily mimicked by synthetic polymers. To sustain the existence of natural rubber in industries, modifications have been made to its chemical structure from time to time in order to obtain new properties and to enable it to be employed in new applications. The chemical structure of natural rubber can be modified by exposure to ultraviolet light to reduce its molecular weight. Under controlled conditions, the natural rubber chains will be broken by photodegradation to yield low-molecular-weight natural rubber. The aim of this work was to obtain what is known as liquid natural rubber via photodegradation, with titanium dioxide nanocrystals as the catalyst. Titanium dioxide, which was firstly synthesized using the sol⁻gel method, was confirmed to be in the form of an anatase, with a size of about 10 nm. In this work, the photodegradation was carried out in latex state and yielded low-molecular-weight natural rubber latex of less than 10,000 g/mol. The presence of hydroxyl and carbonyl groups on the liquid natural rubber (LNR) chains was observed, resulting from the breaking of the chains. Scanning electron microscopy of the NR latex particles showed that titanium dioxide nanocrystals were embedded on the latex surface, but then detached during the degradation reaction.
    MeSH terms: Biopolymers; Microscopy, Electron, Scanning; Microspheres; Molecular Weight; Photolysis; Rubber; Titanium; Ultraviolet Rays; Hydroxyl Radical; Nanoparticles
  15. Fulltext Interfacial Compatibility Evaluation on the Fiber Treatment in the Typha Fiber Reinforced Epoxy Composites and Their Effect on the Chemical and Mechanical Properties
    Rizal S, Ikramullah, Gopakumar DA, Thalib S, Huzni S, Abdul Khalil HPS
    Polymers (Basel), 2018 Nov 28;10(12).
    PMID: 30961241 DOI: 10.3390/polym10121316
    Natural fiber composites have been widely used for various applications such as automotive components, aircraft components and sports equipment. Among the natural fibers Typha spp have gained considerable attention to replace synthetic fibers due to their unique nature. The untreated and alkali-treated fibers treated in different durations were dried under the sun for 4 h prior to the fabrication of Typha fiber reinforced epoxy composites. The chemical structure and crystallinity index of composites were examined via FT-IR and XRD respectively. The tensile, flexural and impact tests were conducted to investigate the effect of the alkali treated Typha fibers on the epoxy composite. From the microscopy analysis, it was observed that the fracture mechanism of the composite was due to the fiber and matrix debonding, fiber pull out from the matrix, and fiber damage. The tensile, flexural and impact strength of the Typha fiber reinforced epoxy composite were increased after 5% alkaline immersion compared to untreated Typha fiber composite. From these results, it can be concluded that the alkali treatment on Typha fiber could improve the interfacial compatibility between epoxy resin and Typha fiber, which resulted in the better mechanical properties and made the composite more hydrophobic. So far there is no comprehensive report about Typha fiber reinforcing epoxy composite, investigating the effect of the alkali treatment duration on the interfacial compatibility, and their effect on chemical and mechanical of Typha fiber reinforced composite, which plays a vital role to provide the overall mechanical performance to the composite.
    MeSH terms: Aircraft; Alkalies; Attention; Dietary Fiber; Epoxy Resins; Microscopy; Reinforcement (Psychology); Spectroscopy, Fourier Transform Infrared; Sports Equipment; Typhaceae; Hydrophobic and Hydrophilic Interactions
  16. Fulltext Effects of Fabric Counts and Weave Designs on the Properties of Laminated Woven Kenaf/Carbon Fibre Reinforced Epoxy Hybrid Composites
    Aisyah HA, Paridah MT, Khalina A, Sapuan SM, Wahab MS, Berkalp OB, et al.
    Polymers (Basel), 2018 Nov 28;10(12).
    PMID: 30961245 DOI: 10.3390/polym10121320
    The effects of different fabric materials namely weave designs (plain and satin) and fabric counts (5 × 5 and 6 × 6) on the properties of laminated woven kenaf/carbon fibre reinforced epoxy hybrid composites were evaluated. The hybrid composites were fabricated from two types of fabric, i.e., woven kenaf that was made from a yarn of 500tex and carbon fibre, by using vacuum infusion technique and epoxy resin as matrix. The panels were tested for tensile, flexural, and impact strengths. The results have revealed that plain fabric is more suitable than satin fabric for obtaining high tensile and impact strengths. Using a fabric count of 5 × 5 has generated composites that are significantly higher in flexural modulus as compared to 6 × 6 which may be attributed to their structure and design. The scanned electron micrographs of the fractured surfaces of the composites demonstrated that plain woven fabric composites had better adhesion properties than satin woven fabric composites, as indicated by the presence of notably lower amount of fibre pull out.
  17. Fulltext UV-Curable Urethane Acrylate Resin from Palm Fatty Acid Distillate
    Teo KT, Hassan A, Gan SN
    Polymers (Basel), 2018 Dec 11;10(12).
    PMID: 30961299 DOI: 10.3390/polym10121374
    Palm fatty acid distillate (PFAD), is a by-product of the crude palm oil refining process. It comprises mainly of free fatty acids-around 45% palmitic and 33% oleic acids-as the major components. Ultra-violet (UV) curable urethane acrylate (UA) oligomers could be synthesized from PFAD, by the following procedure. A hydroxyl terminated macromer was first prepared by reacting PFAD with a mixture of isophthalic acid, phthalic anhydride, neopentagylcol (NPG), and pentaerythritol. The macromer was then reacted with 2-hydroxylethylacrylate (2HEA) and toluene diisocynate (TDI) to generate a resin, containing acrylate side chains for UV curable application. A series of UA resins were prepared by using 15, 25, 45, 55, and 70% of PFAD, respectively. The UA resin has Mw in the range of 3,200 to 27,000. They could be cured by UV irradiation at an intensity of 225 mW/cm². Glass transition temperature (Tg) of the cured film was measured by differential scanning calorimeter (DSC), and hardness of the film was determined by a pendulum hardness tester, according to American Society for Testing and Materials (ASTM)4366. The resins were used in a wood-coating application. All of the cured films showed good adhesion, hardness, and chemical resistance except for the one using the 70% PFAD, which did not cure properly.
    MeSH terms: Acrylic Resins; Fatty Acids, Nonesterified; Oleic Acids; Petroleum; Phthalic Anhydrides; Polyurethanes; Propylene Glycols; Toluene; United States; Wood; Transition Temperature
  18. Fulltext Electrospun Polycaprolactone Nanofibers as a Reaction Membrane for Lateral Flow Assay
    Yew CHT, Azari P, Choi JR, Muhamad F, Pingguan-Murphy B
    Polymers (Basel), 2018 Dec 14;10(12).
    PMID: 30961312 DOI: 10.3390/polym10121387
    Electrospun polycaprolactone (PCL) nanofibers have emerged as a promising material in diverse biomedical applications due to their various favorable features. However, their application in the field of biosensors such as point-of-care lateral flow assays (LFA) has not been investigated. The present study demonstrates the use of electrospun PCL nanofibers as a reaction membrane for LFA. Electrospun PCL nanofibers were treated with NaOH solution for different concentrations and durations to achieve a desirable flow rate and optimum detection sensitivity in nucleic acid-based LFA. It was observed that the concentration of NaOH does not affect the physical properties of nanofibers, including average fiber diameter, average pore size and porosity. However, interestingly, a significant reduction of the water contact angle was observed due to the generation of hydroxyl and carboxyl groups on the nanofibers, which increased their hydrophilicity. The optimally treated nanofibers were able to detect synthetic Zika viral DNA (as a model analyte) sensitively with a detection limit of 0.5 nM. Collectively, the benefits such as low-cost of fabrication, ease of modification, porous nanofibrous structures and tunability of flow rate make PCL nanofibers a versatile alternative to nitrocellulose membrane in LFA applications. This material offers tremendous potential for a broad range of point-of-care applications.
  19. Fulltext Experimental and theoretical investigation of sensing parameters in carbon nanotube-based DNA sensor
    Nouri M, Meshginqalam B, Sahihazar MM, Sheydaie Pour Dizaji R, Ahmadi MT, Ismail R
    IET Nanobiotechnol, 2018 Dec;12(8):1125-1129.
    PMID: 30964025 DOI: 10.1049/iet-nbt.2018.5068
    Nowadays, sensitive biosensors with high selectivity, lower costs and short response time are required for detection of DNA. The most preferred materials in DNA sensor designing are nanomaterials such as carbon and Au nanoparticles, because of their very high surface area and biocompatibility which lead to performance and sensitivity improvements in DNA sensors. Carbon nanomaterials such as carbon nanotubes (CNTs) can be considered as a suitable DNA sensor platform due to their high surface-to-volume ratio, favourable electronic properties and fast electron transfer rate. Therefore, in this study, the CNTs which are synthesised by pulsed AC arc discharge method on a high-density polyethylene substrate are used as conducting channels in a chemiresistor for the electrochemical detection of double stranded DNA. Moreover, the response of the proposed sensor is investigated experimentally and analytically in different temperatures, which confirm good agreement between the presented model and experimental data.
    MeSH terms: DNA/analysis*; Equipment Design; Biosensing Techniques/instrumentation*; Polyethylene/chemistry; Nanotubes, Carbon/chemistry*
  20. Fulltext Rare and lethal complication of barium enema intravasation
    Loo GH, Marzuki F, Henry F
    BJR Case Rep, 2018 Dec;4(4):20180017.
    PMID: 30931138 DOI: 10.1259/bjrcr.20180017
    Barium enema investigation is regarded as a safe investigative procedure. Rarely, it may cause complications such as colonic perforation and barium intravasation. Barium intravasation may be caused by the inadvertent introduction of the catheter into the vagina, thereby into the vaginal venous plexus. It may also occur through mechanical colonic perforation with the catheter, or via diseased bowel conditions. This may lead to complications such as liver microabscesses, massive pulmonary embolism, hypovolemic shock, disseminated intravascular coagulopathy and even sudden death. With that in mind, we would like to report an interesting case of barium intravasation into the portal venous system via the vagina venous plexus. The patient experienced abdominal discomfort with mild per vaginal bleed and went into disseminated intravascular coagulopathy. She received supportive management and she made a full recovery.
    MeSH terms: Barium; Colonic Diseases; Death, Sudden; Female; Humans; Intestinal Perforation; Liver; Pulmonary Embolism; Shock; Vagina; Hypovolemia; Barium Enema
External Links