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1.
Nishio M Xu L Sasaki M Haga S Okumoto M Mori N Sarkar NH Acha-Orbea H Enami J Imai S 《Breast cancer (Tokyo, Japan)》1994,1(2):89-94
Mammary tumors of a newly isolated strain of Chinese wild mouse (JYG mouse) harbor exogenous mouse mammary tumor virus (MMTV). The complete nucleotide sequence of exogenous JYG-MMTV was determined on the proviral 5' long terminal repeat (LTR)(partial)-gag-pol-env-3' LTR (partial) fragment cloned into a plasmid vector and the cDNA sequence from JYG-MMTV producing cells. Similarly to the other MMTV species the LTR of JYG-MMTV contains an open reading frame (ORF). The amino acid sequence of the JYG-MMTV ORF resembles that of SW-MMTV (92% identity) and endogenous Mtv-7 (93% identity) especially at the C-terminal region. Thus, a functional similarity in T-cell receptor V beta recognition as a superantigen is implicated among these MMTV species. Analysis of the viral gag nucleotide sequence revealed that this gene is not disrupted by the bacterial insertion sequence IS1 or IS2, which have been reported to be present in the majority of the plasmids containing the gag region. Comparison of amino acid sequences of JYG-MMTV with those of BR6-MMTV showed that over 96% of the amino acids of gag, pol, protease and env products are identical. These results suggest the intact nature of the nucleotide sequence of the near full-length MMTV genome cloned in the plasmid. 相似文献
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Ramez A. Al-Mansob Herda Yati Katman Abdulnaser M. Al-Sabaeei Muhammad Zamzami Amin Al-Fakih Willy Kuay Wei Taha M. Jassam Jamal Alsharef Salihah B. Surol Nurul H. Yusof Suhana Koting 《Materials》2022,15(11)
This study aimed to evaluate the effects of carbon nanofibers (CNFs) on the performance of liquid epoxidized natural rubber (LENR)-modified asphalt. The physical, adhesion and rheological properties were determined by several tests such as penetration, elastic recovery, ring and ball softening point, Brookfield rotational viscometer, AFM and dynamic shear rheometer. LENR was used at concentrations of 3, 6, and 9%, while CNFs were used at contents of 0.3, 0.4, and 0.5% by weight of asphalt. Conventional test results showed that the increases in LENR and LENR/CNFs composite contents in binder leads to an increase in the hardness and consistency and a reduction in the temperature susceptibility of base asphalt. Adhesion results revealed that the addition of CNFs significantly increases the adhesion and bonding properties of base and rubberized binders. Rheological properties analysis exhibited that LENR improved the viscoelastic properties and permanent deformation resistance of asphalt at different temperatures and frequencies. On the other hand, it was found that the addition of CNFs significantly improves the stiffness, elasticity, and hardness of LENR-modified binders. The 6% LENR and 0.4% CNFs were found to be the optimum to enhance the physical, adhesion, and rheological properties of asphalt in this study. Thus, it can be stated that the addition of CNFs is promising to improve the performance of rubberized binders for high temperature applications. 相似文献
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Shanti Raman Krishnamachari Srinivasan Anura Kurpad Jan Ritchie Husna Razee 《Health care for women international》2016,37(10):1119-1137
The limited autonomy and agency of women in developing countries is recognized as a key barrier to improving their reproductive health. Using an existing perinatal cohort in urban South India, we interviewed 36 women who had recently been through childbirth, and we carried out observations of family life and clinic encounters. Critical domains involved in women's agency and autonomy were women's participation in employment and group action and their mobility. Household decision making was considered a joint rather than individual responsibility. We call for a more nuanced understanding of these domains and their relationship to women's reproductive health, particularly for urban populations. 相似文献
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Nurul Absar M. Mashiur Rahman Masud Kamal Naziba Siddique Mantazul Islam Chowdhury 《Journal of radiation research》2014,55(6):1075-1080
Radioactivity in the soil of a tea garden in the Fatickchari area in Chittagong, Bangladesh, was measured using a high-resolution HPGe detector. The soil samples were collected from depths of up to 20 cm beneath the soil surface. The activity concentrations of naturally occurring 238U and 232Th were observed to be in the range of 27 ± 7 to 53 ± 8 Bq kg−1 and 36 ± 11 to 72 ± 11 Bq kg−1, respectively. The activity concentration of 40K ranged from 201 ± 78 to 672 ± 81 Bq kg−1, and the highest activity of fallout 137Cs observed was 10 ± 1 Bq kg−1. The average activity concentration observed for 238U was 39 ± 8 Bq kg−1, for 232Th was 57 ± 11 Bq kg−1, for 40K was 384 ± 79 Bq kg−1 and for 137Cs was 5 ± 0.5 Bq kg−1. The radiological hazard parameters (representative level index, radium equivalent activity, outdoor and indoor dose rates, outdoor and indoor annual effective dose equivalents, and radiation hazard index) were calculated from the radioactivity in the soil. 相似文献
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Siti Samahani Suradi Nurul Hazlina Naemuddin Shahrir Hashim Nadia Adrus 《RSC advances》2018,8(24):13423
Novel hydrogel-modified textiles have been prepared through photografting poly(N-isopropylacrylamide) (PNIPAAm) onto pristine and functionalised polyethylene terephthalate (PET) surfaces. In this work, two types of functionalisation, carboxylation (CPET) and hydrolysis (HPET), were performed to scrutinise the hydrogel grafting efficiency. Basic characterisation of the pristine, functionalised and grafted textiles was carried out via fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM) analyses. Then, the functional characteristics of these samples were determined based on the oil staining performance. Functionalisation of the PET textiles via hydrolysis and carboxylation gives rise to different chemical reactivity and interactions on the PET surface. Impressively, the surface formed via hydrolysis functionalisation of PET was found to be more efficient compared to that formed via carboxylation, and the untreated one. The HPET surface was remarkably more hydrophilised and rougher than both the UPET and CPET surfaces. The accessibility of the –OH groups for hydrogen abstraction from HPET has a great impact on the hydrogel grafting onto the HPET surface. All the grafted textiles (PNIPAAm-g-UPET, PNIPAAm-g-CPET and PNIPAAm-g-HPET) demonstrated anti-oil staining behaviour at 27 °C. In particular, PNIPAAm-g-HPET textiles with a high degree of grafting (DG) exhibited the fastest rate for oil to de-stain from the surface. Moreover, the reversible transition of PNIPAAm hydrogels around the lower critical solution temperature (LCST) ∼ 32 °C from hydrophilic to hydrophobic generates switchable surfaces of the textiles with regard to the oil wettability. Specifically, PNIPAAm-g-HPET textiles also displayed the highest degree of wettability switching as a result of having the highest DG. Taken together, the PNIPAAm hydrogels grafted onto PET textiles were significantly enhanced though hydrolysis functionalisation and possessed excellent switchable surfaces toward oil-staining, having great potential to be used for applications in oil and water separation as well as smart textiles.Functionalisation, especially via hydrolysis, has created efficient PNIPAAm hydrogels grafted onto PET textiles with superior anti-oil staining performance. 相似文献
10.
Nurul Asma Samsudin Zulkarnain Zainal Hong Ngee Lim Yusran Sulaiman Sook-Keng Chang Ying-Chin Lim Asmaa Kadim Ayal Wardatun Nadrah Mohd Amin 《RSC advances》2018,8(41):23040
In this study, a composite material, manganese oxide/reduced titania nanotubes (Mn2O3/R-TNTs), was synthesized through incorporation of Mn2O3 onto R-TNTs via the reverse pulse electrodeposition technique. The influence of pulse reverse duty cycles on the morphological, structural and electrochemical performance of the surface was studied by varying the applied duty cycle from 10% to 90% for 5 min total on-time at an alternate potential of −0.90 V (Eon) and 0.00 V (Eoff). FESEM analysis revealed the uniform deposition of Mn2O3 on the circumference of the nanotubes. The amount of Mn2O3 loaded onto the R-TNTs increased as a higher duty cycle was applied. Cyclic voltammetry and galvanostatic charge–discharge tests were employed to elucidate the electrochemical properties of all the synthesized samples in 1 M KCl. The specific capacitance per unit area was greatly enhanced upon the incorporation of Mn2O3 onto R-TNTs, but showed a decrease as a high duty cycle was applied. This proved that low amounts of Mn2O3 loading enhanced the facilitation of the active ions for charge storage purposes. The optimized sample, Mn2O3/R-TNTs synthesized at 10% duty cycle, exhibited high specific capacitance of 18.32 mF cm−2 at a current density of 0.1 mA cm−2 obtained from constant current charge–discharge measurements. This revealed that the specific capacitance possessed by Mn2O3/R-TNTs synthesized at 10% duty cycle was 6 times higher than bare R-TNTs.Mn2O3 was coated onto reduced titania nanotubes by reverse pulse electrodeposition, showing smooth and homogenous deposits without covering the opening of the nanotubes. 相似文献