Abrasive wear failure analysis of tungsten carbide hard facing on carbon steel blade

This study investigate the abrasive wear failure of tungsten carbide hardfacing on continuous digester (CD) blade (carbon steel) in an environment of sulphuric acid and ilmenite ore mixture. Comparison being made on the hardness, thickness and microstructural of the hardfacing between unworn and 3 months old worn blade on few locations around the blade. The cross sections of the blade revealed non-uniform coverage of the hardfacing on the blade for both worn and unworn blade. The edge of the blade has the least amount of hardfacing thickness which with time acts as the point of failure during the wear process. The hardness obtained from both the unworn and worn samples are around 25% lower from the hardfacing electrode manufacturer’s hardness specification. Microstructural micrograph analysis of the hardfacing revealed non uniform size carbide with non-uniform distributed of carbide in the hardfacing layer

The Risk of Recurrence in Breast Cancer Patients Treated with Tamoxifen: Polymorphisms of CYP2D6 and ABCB1

CYP2D6 plays a major role in the metabolism of tamoxifen, and polymorphism of Pglycoprotein has been associated with resistance of many drug therapies. This study investigates the clinical impact of genetic variants of CYP2D6 and ABCB1 in breast cancer patients treated with tamoxifen. Blood samples from 95 breast cancer patients treated with tamoxifen were collected and genotyped for CYP2D6 and ABCB1 variants using allele-specific PCR method. Recurrence risks were calculated using Kaplan–Meier analysis and compared using the log-rank test. Patients carrying CYP2D6*10/*10 and heterozygous null allele (IM) showed higher risks of developing recurrence and metastasis (OR 13.14; 95% CI 1.57–109.94; P=0.004) than patients with CYP2D6*1/*1 and *1/*10 genotypes. Patients with homozygous CC genotypes of ABCB1 C3435T showed a shorter time to recurrence. Patients who were CYP2D6 IM and homozygous CC genotype of C3435T have statistically significant higher risks of recurrence (P=0.002). Similarly, median time to recurrence in these patients was only 12 months (95% CI=0.79–23.2) compared to those without this combination which was 48 months (95% CI=14.7–81.2). Patients with CYP2D6 IM and homozygous CC genotype of ABCB1 C3435T have shorter times to recurrence. The results confirmed the findings of previous studies and support FDA recommendation to perform pre-genotyping in patients before the choice of therapy is determined in breast cancer patients

A putative antiviral role of plant cytidine deaminases

[EN] Background: A mechanism of innate antiviral immunity operating against viruses infecting mammalian cells has been described during the last decade. Host cytidine deaminases (e.g., APOBEC3 proteins) edit viral genomes, giving rise to hypermutated nonfunctional viruses; consequently, viral fitness is reduced through lethal mutagenesis. By contrast, sub-lethal hypermutagenesis may contribute to virus evolvability by increasing population diversity. To prevent genome editing, some viruses have evolved proteins that mediate APOBEC3 degradation. The model plant Arabidopsis thaliana genome encodes nine cytidine deaminases (AtCDAs), raising the question of whether deamination is an antiviral mechanism in plants as well. Methods: Here we tested the effects of expression of AtCDAs on the pararetrovirus Cauliflower mosaic virus (CaMV). Two different experiments were carried out. First, we transiently overexpressed each one of the nine A. thaliana AtCDA genes in Nicotiana bigelovii plants infected with CaMV, and characterized the resulting mutational spectra, comparing them with those generated under normal conditions. Secondly, we created A. thaliana transgenic plants expressing an artificial microRNA designed to knock-out the expression of up to six AtCDA genes. This and control plants were then infected with CaMV. Virus accumulation and mutational spectra where characterized in both types of plants. Results: We have shown that the A. thaliana AtCDA1 gene product exerts a mutagenic activity, significantly increasing the number of G to A mutations in vivo, with a concomitant reduction in the amount of CaMV genomes accumulated. Furthermore, the magnitude of this mutagenic effect on CaMV accumulation is positively correlated with the level of AtCDA1 mRNA expression in the plant. Conclusions: Our results suggest that deamination of viral genomes may also work as an antiviral mechanism in plants.This work was supported by the former Spanish Ministerio de Ciencia e Innovación-FEDER grant BFU2009-06993 to SFE. JMC was supported by the CSIC JAE-doc program/Fondo Social Europeo. AG-P was supported by a grant for Scientific and Technical Activities and by grant P10-CVI-65651, both from Junta de Andalucía.Martín, S.; Cuevas, J.; Grande-Perez, A.; Elena Fito, SF. (2017). A putative antiviral role of plant cytidine deaminases. F1000Research. 1-14. https://doi.org/10.12688/f1000research.11111.2S11

Liposome as transdermal carrier for labisia pumila and ficus deltoidea water extracts

In this study, liposome has been investigated as the potential transdermal carrier for Labisia pumila (Lp) and Ficus deltoidea (Fd). The encapsulation efficiency, zeta potential, particle size and transdermal transport properties of the herbal extracts loaded liposomes were determined to characterize the delivery system. The entrapment efficiency for Lipo-Lp and Lipo-Fd were 35.47 ± 2.71% and 31.23 ± 7.65%, respectively. The average diameter were153.35nm and 131.9nm, respectively and the zeta potential were -47.2 and -46.8, respectively. The permeability and partition coefficient (K) of Lipo-Lp were 1.31cm h-1 and 10.05, respectively and the permeability and partition coefficient (K) of Lipo-Fd were 1.28cm h-1 and 7.62, respectively. Labisia pumila and Ficus deltoidea loaded liposomes showed better transdermal permeation compared to un-encapsulated Labisia pumila and Ficus deltoidea indicative of potential actives herbal cosmetic formulations

Factor analysis of motorcycle crashes in Malaysia

This research paper focused on factor analysis of motorcycle crashes in Malaysia. Statistics have shown that Malaysia has the highest road fatality risk (per 100,000 populations) among the ASEAN countries and more than 50% of the road accident fatalities involve motorcyclists. The research literature has shown that key factors that significantly involve in the motorcycles crashes are human factors, road and vehicle conditions and environment factors. The purpose of this research is to analyse the driving attitude, behaviour and habits of Malaysian motorcyclists especially the young students. For this purpose, a research survey (N=210) has been conducted in University Technology Malaysia (UTM) in order to perceive road user perception on key factors that contribute to motorcycle crashes in Malaysia among the young students. The results show that the highest factor that contributes to the motorcycle crashes in Malaysia is the human behavior factor, follow by road and vehicle and lastly the environment factor. Human attitude on the road is the main factor that causes a motorcycle crash. Impatience, careless, selfish and dangerous driving make driver involve an accident. Evidence recommendations are suggested to reduce the number motorcycle crash in Malaysia. Implementation of these recommendations can be helpful to reduce the number of accidents and changing the attitude of young driver

Retransmission-Based Additional TXOP Allocation for Audio-Video Transmission by IEEE 802.11e HCCA

This paper proposed a method of allocating additional TXOP duration to replenish the bandwidth used during the retransmission of frames at link layer in audio-video transmission by IEEE 802.11e HCCA. In the proposed scheme, the HC monitors the number of retransmission at link layer and utilize the surplus bandwidth to allocate additional TXOP duration on the basis of number of retransmission performed during the last transmission. The proposed scheme also reduces the polling overhead to gain surplus bandwidth by polling only a station in a polling interval. By simulation, we compare the application-level QoS of the TGe scheme and the proposed scheme. Numerical results show that the proposed scheme can keep the QoS of audio and video high under lossy wireless channel especially when the number of multimedia stations is small. Furthermore, the proposed scheme can admit more traffic flows than the TGe scheme

Coordinated SPD systems for mitigating the effect of lightning-induced voltage on hybrid solar PV-battery energy storage system

This paper discusses the effect of lightning-induced voltage on a hybrid solar photovoltaic (PV)-battery energy storage system (BESS) without an external lightning protection system (LPS). Solar PV generates electricity by converting solar energy and providing it to the user. In addition, battery energy storage is also utilised to supply consistency and satisfy the need for energy. However, because the system is installed in open spaces, lightning has always been a huge difficulty for it to work at optimal efficiency. In this paper, the single SPD Class I was installed near the inverter on the DC side. The study on cable length with various lightning current amplitude and lightning strike distance is conducted. The simulation findings found that the inverter is well protected by the SPD whereby the impulse withstand voltage is 6 kV, however, the solar PV-BESS is affected by the lightning-induced voltage regardless of any cable length. In this way, providing the requirement for an adequate SPD installation will ensure improved maintenance and extend the equipment’s lifespan