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A computational and experimental study on acoustic pressure for ultrasonically formed oil-in-water emulsion

Tiong TJ, Chu JK, Lim LY, Tan KW, Hong Yap Y, Asli UA

Ultrason Sonochem, 2019 Sep;56:46-54.
PMID: 31101285 DOI: 10.1016/j.ultsonch.2019.03.026

In the field of ultrasonic emulsification, the formation and cavitation collapse is one major factor contributing to the formation of micro- and nano-sized emulsion droplets. In this work, a series of experiments were conducted to examine the effects of varying the ultrasonic horn's position to the sizes of emulsion droplets formed, in an attempt to compare the influence of the simulated acoustic pressure fields to the experimental results. Results showed that the intensity of the acoustic pressure played a vital role in the formation of smaller emulsion droplets. Larger areas with acoustic pressure above the cavitation threshold in the water phase have resulted in the formation of smaller emulsion droplets ca. 250 nm and with polydispersity index of 0.2-0.3. Placing the ultrasonic horn at the oil-water interface has hindered the formation of small emulsion droplets, due to the transfer of energy to overcome the interfacial surface tension of oil and water, resulting in a slight reduction in the maximum acoustic pressure, as well as the total area with acoustic pressures above the cavitation threshold. This work has demonstrated the influence of the position of the ultrasonic horn in the oil and water system on the final emulsion droplets formed and can conclude the importance of generating acoustic pressure above the cavitation threshold to achieve small and stable oil-in-water emulsion.
Non-aqueous foams formed by whipping diacylglycerol stabilized oleogel

Lei M, Zhang N, Lee WJ, Tan CP, Lai OM, Wang Y, et al.

Food Chem, 2020 May 15;312:126047.
PMID: 31884300 DOI: 10.1016/j.foodchem.2019.126047

Formation of foams is critical for tailoring the texture and mouthfeel of fat-based products. Diacylglycerol (DAG) is regarded as a preferable alternative structurant to hydrogenated lipid. Effect of DAG concentration (2-10 wt%) on the characteristics of oleogels and foams including crystal polymorphisms, size and distribution, rheological and thermodynamic properties was investigated. Oleogel prepared with 10 wt% DAG had comparable whipping and foaming stability to that of 6 wt% fully hydrogenated palm oil (FHPO). DAG formed small plate-crystals which tend to occur at the bubble surface, whereas FHPO showed needle-like crystals that were formed mainly in the continuous phase. For the 2 wt% FHPO-8 wt% DAG-based oil foams, interfacial templating crystallization effect contributed to the smaller bubble size and improved rheological properties whereby less oil drainage and foam breakdown occurred. Hence, the non-aqueous foam formed by DAG has broad application prospect because of the thermoresponsive properties and the desirable health benefits.
Electrospun cellulose acetate butyrate/polyethylene glycol (CAB/PEG) composite nanofibers: A potential scaffold for tissue engineering

Tan HL, Kai D, Pasbakhsh P, Teow SY, Lim YY, Pushpamalar J

Colloids Surf B Biointerfaces, 2020 Apr;188:110713.
PMID: 31884080 DOI: 10.1016/j.colsurfb.2019.110713

Electrospinning is a common method to prepare nanofiber scaffolds for tissue engineering. One of the common cellulose esters, cellulose acetate butyrate (CAB), has been electrospun into nanofibers and studied. However, the intrinsic hydrophobicity of CAB limits its application in tissue engineering as it retards cell adhesion. In this study, the properties of CAB nanofibers were improved by fabricating the composite nanofibers made of CAB and hydrophilic polyethylene glycol (PEG). Different ratios of CAB to PEG were tested and only the ratio of 2:1 resulted in smooth and bead-free nanofibers. The tensile test results show that CAB/PEG composite nanofibers have 2-fold higher tensile strength than pure CAB nanofibers. The hydrophobicity of the composite nanofibers was also reduced based on the water contact angle analysis. As the hydrophilicity increases, the swelling ability of the composite nanofiber increases by 2-fold with more rapid biodegradation. The biocompatibility of the nanofibers was tested with normal human dermal fibroblasts (NHDF). The cell viability assay results revealed that the nanofibers are non-toxic. In addition to that, CAB/PEG nanofibers have better cell attachment compared to pure CAB nanofibers. Based on this study, CAB/PEG composite nanofibers could potentially be used as a nanofiber scaffold for applications in tissue engineering.
Fulltext University Students' Notion of Autism Spectrum Conditions: A Cross-Cultural Study

de Vries M, Cader S, Colleer L, Batteux E, Yasdiman MB, Tan YJ, et al.

J Autism Dev Disord, 2020 Apr;50(4):1281-1294.
PMID: 31901119 DOI: 10.1007/s10803-019-04343-z

Cultural background might influence knowledge and attitudes regarding autism, influencing willingness to interact. We studied whether beliefs, knowledge, contact, and attitude differed between the UK and Malaysia. With mediation analyses, we studied how these factors influenced willingness to interact. Autism was more often linked to food in the UK, and to upbringing in Malaysia. Knowledge, contact, and acceptance were greater in the UK. When excluding psychology students, Malaysian students were less willing to interact with autistic people. Knowledge and contact appeared to improve acceptance, but acceptance did not mediate the relation between country, beliefs, knowledge, and experience; and willingness to interact. Knowledge and contact regarding autism might improve acceptance in different cultures, but how acceptance could improve interaction is unclear.
Fulltext Survival Rates and Associated Factors of Colorectal Cancer Patients in Brunei Darussalam

Leong E, Ong SK, Madli F, Tan A, Lai D, Basir N, et al.

Asian Pac J Cancer Prev, 2020 Jan 01;21(1):259-265.
PMID: 31983194 DOI: 10.31557/APJCP.2020.21.1.259

BACKGROUND: Colorectal cancer (CRC) is the third most common cancer in both men and women. In most Asian countries, both the incidence and mortality rates of CRC are gradually increasing. In Brunei Darussalam, CRC ranks first and second in lifetime risk among men and women respectively. This study aims to report the overall survival rates and associated factors of CRC in Brunei Darussalam.
METHODS: This is a retrospective study examining CRC data for the period 2007 to 2017 retrieved from a population based cancer registry in Brunei Darussalam. A total of 728 patients were included in the analysis. Kaplan Meier method was used to estimate survival rates. Univariate analysis using log-rank test was used to examine the differences in survival between groups. Multivariate analysis using Cox PH regression was used to estimate hazard of death and obtain significant predictors that influence CRC patients' survival.
RESULTS: The median survival time for colorectal, colon and rectal cancer patients were 57.0, 85.8 and 40.0 months respectively. The overall 1-, 3- and 5- year survival rates for CRC patients were 78.0%, 57.7% and 49.6% respectively. In univariate analysis, age at diagnosis, ethnicity, cancer stage, tumour location and histology were found to have significant difference in CRC patients' survival. In the Cox PH analysis, older age (≥70 years), cancer stage, ethnicity and other histological type were determined as associated factors of CRC patients' survival.
CONCLUSION: This study found the overall 5-year survival rate of CRC in Brunei Darussalam is similar to that in some Asian countries such as Singapore and Malaysia. However, more efforts need to be carried out in order to raise awareness of CRC and improve the survival of CRC patients.
Polymorphisms in the androgen receptor CAG repeat sequence are related to tumour stage but not to ERG or androgen receptor expression in Malaysian men with prostate cancer

Tan JSJ, Ong KC, Ong DBL, Wu YS, Razack A, Kuppusamy S, et al.

Malays J Pathol, 2019 Dec;41(3):243-251.
PMID: 31901908

INTRODUCTION: Polymorphic expression of a CAG repeat sequence in the androgen receptor (AR) gene may influence the activity of the AR and the occurrence of prostate cancer and the TMPRSS2-ERG fusion event. Furthermore, this polymorphism may be responsible for the ethnic variation observed in prostate cancer occurrence and expression of the ERG oncogene. We investigate the expression of AR and ERG in the biopsies of Malaysian men with prostate cancer and in the same patients relate this to the length of the CAG repeat sequence in their AR gene.
MATERIALS AND METHODS: From a PSA screening initiative, 161 men were shown to have elevated PSA levels in their blood and underwent prostatic tissue biopsy. DNA was extracted from the blood, and exon 1 of the AR gene amplified by PCR and sequenced. The number of CAG repeat sequences were counted and compared to the immunohistochemical expression of ERG and AR in the matched tumour biopsies.
RESULTS: Of men with elevated PSA, 89 were diagnosed with prostate cancer, and 72 with benign prostatic hyperplasia (BPH). There was no significant difference in the length of the CAG repeat in men with prostate cancer and BPH. The CAG repeat length was not associated with; age, PSA or tumour grade, though a longer CAG repeat was associated with tumour stage. ERG and AR were expressed in 36% and 86% of the cancers, respectively. There was no significant association between CAG repeat length and ERG or AR expression. However, there was a significant inverse relationship between ERG and AR expression. In addition, a significantly great proportion of Indian men had ERG positive tumours, compared to men of Malay or Chinese descent.
CONCLUSIONS: CAG repeat length is not associated with prostate cancer or expression of ERG or AR. However, ERG appears to be more common in the prostate cancers of Malaysian Indian men than in the prostate cancers of other Malaysian ethnicities and its expression in this study was inversely related to AR expression.
Fulltext Induction approach via P-Graph to rank clean technologies

Low CX, Ng WY, Putra ZA, Aviso KB, Promentilla MAB, Tan RR

Heliyon, 2020 Jan;6(1):e03083.
PMID: 31909259 DOI: 10.1016/j.heliyon.2019.e03083

Identification of appropriate clean technologies for industrial implementation requires systematic evaluation based on a set of criteria that normally reflect economic, technical, environmental and other aspects. Such multiple attribute decision-making (MADM) problems involve rating a finite set of alternatives with respect to multiple potentially conflicting criteria. Conventional MADM approaches often involve explicit trade-offs in between criteria based on the expert's or decision maker's priorities. In practice, many experts arrive at decisions based on their tacit knowledge. This paper presents a new induction approach, wherein the implicit preference rules that estimate the expert's thinking pathways can be induced. P-graph framework is applied to the induction approach as it adds the advantage of being able to determine both optimal and near-optimal solutions that best approximate the decision structure of an expert. The method elicits the knowledge of experts from their ranking of a small set of sample alternatives. Then, the information is processed to induce implicit rules which are subsequently used to rank new alternatives. Hence, the expert's preferences are approximated by the new rankings. The proposed induction approach is demonstrated in the case study on the ranking of Negative Emission Technologies (NETs) viability for industry implementation.
Fulltext Roles of Carotenoids in Invertebrate Immunology

Tan K, Zhang H, Lim LS, Ma H, Li S, Zheng H

Front Immunol, 2019;10:3041.
PMID: 32010132 DOI: 10.3389/fimmu.2019.03041

Carotenoids are biologically active pigments that are well-known to enhance the defense and immunity of the vertebrate system. However, in invertebrates, the role of carotenoids in immunity is not clear. Therefore, this study aims to review the scientific evidence for the role of carotenoids in invertebrate immunization. From the analysis of published literatures and recent studies from our laboratory, it is obvious that carotenoids are involved in invertebrate immunity in two ways. On the one hand, carotenoids can act as antioxidant enzymes to remove singlet oxygen, superoxide anion radicals, and hydroxyl radicals, thereby reducing SOD activity and reducing the cost of immunity. In some organisms, carotenoids have been shown to promote SOD activity by up-regulating the expression of the ZnCuSOD gene. Carotenoids, on the other hand, play a role in the expression and regulation of many genes involved in invertebrate immunity, including thioredoxins (TRX), peptidoglycan recognition receptor proteins (PGRPs), ferritins, prophenoloxidase (ProPO), vitellogenin (Vg), toll-like receptor (TLRs), heat shock proteins (HSPs), and CuZnSOD gene. The information in this review is very useful for updating our understanding of the progress of carotenoid research in invertebrate immunology and to help identify topics for future topics.
Prevalence and factors of verbal learning and memory dysfunction in patients with epilepsy - A single centre study

Subramaniam SR, Khoo CS, Raymond AA, Che Din N, Syed Zakaria SZ, Tan HJ

J Clin Neurosci, 2020 Mar;73:31-36.
PMID: 32094071 DOI: 10.1016/j.jocn.2020.02.003

The objective of this study is to determine prevalence and factors leading to verbal learning and memory dysfunction among patients with epilepsy. A total of 211 subjects were recruited. Their verbal memory was assessed by Rey's Auditory Verbal Learning Test (RAVLT). This test was further subdivided into four major spheres for analysis, namely the verbal learning, interference list, immediate memory and delayed memory. All data collected were analyzed using Statistical Package for Social Sciences. Among the 211 patients, 55% (n = 116) had focal seizures and the remaining 45% (n = 95) had generalized seizures. Prevalence of verbal learning and memory impairment was high at 39.97% overall, and found most commonly in patients with focal impaired awareness seizures. Verbal learning and immediate memory dysfunction were significantly lower in focal impaired awareness group compared to others. Age more than 50 years, exposure to three or more antiepileptic drugs and use of carbamazepine more than 1000 mg a day were the predictors in poor verbal memory outcome. No statistical difference was observed in the mean RAVLT scores among the gender and hand dominance groups. Between patients with and without electroencephalogram changes as well as brain magnetic resonance imaging changes, the mean RAVLT scores showed no statistically significant difference. Verbal learning and memory impairment is prevalent among the epilepsy patients. The consequences of the memory impairment can be as debilitating as the seizure control. RAVLT is a reliable and practical test in the clinical setting.
Fulltext Cerebral Lupus and Cryptococcal Meningitis in a Pregnant Woman

Khoo CS, Marzukie MM, Yap SS, Wan Yahya WNN, Tan HJ

J Neurosci Rural Pract, 2020 Jan;11(1):183-186.
PMID: 32140026 DOI: 10.1055/s-0039-3402895

Systemic lupus erythematosus (SLE) is a chronic autoimmune and multisystem disorder, which frequently affects young women. During pregnancy, SLE flares could occur up to 65%, with renal and hematological manifestations being the most common. However, reports on neuropsychiatric lupus in pregnant women are scarce. We herein report a 26-year-old lupus pregnant woman, who had cerebral lupus with concurrent cryptococcal meningitis. This case highlights the complexity in diagnosing and managing our patient to achieve the best outcome for both the mother and infant.
Fulltext Awareness of cancer cervix and its prevention among students in Melaka, Malaysia

De S, Selvan VT, Tan J, Soe HHK, Sahoo S, Sahoo R

J Educ Health Promot, 2019;8:231.
PMID: 31867395 DOI: 10.4103/jehp.jehp_379_19

BACKGROUND: Cancer cervix is caused by human papillomavirus (HPV), oncogenic virus and has vaccines and screening as its preventive measures. This study analyzes the change in awareness and attitudes of nonmedical students toward the condition following the use of an educational module.
METHODOLOGY: The study design was quasi-experimental. The interprofessional (IP) team implemented an educational module and analyzed the difference in awareness of young individuals toward the cancer cervix. A pretest and posttest written questionnaire, customized for both genders, was administered with the intervention of the educational module in between. The module consisted of a short educational presentation along with a group activity. A follow-up survey was also done after 2 months to check the attrition of awareness. The statistical analysis was done using MacNemar test using SPSS 12 IBM software and significance of differences were determined.
RESULTS: There was a significant improvement of knowledge and awareness on linkage between HPV and cervical cancer (P < 0.001). There was also significant change with regard to attitudes toward cervical cancer vaccination (P = 0.004). The knowledge of HPV linkage to the malignancy was maintained after 2 months of gap. The subjects also wished for more future awareness program.
CONCLUSIONS: There is improved awareness in the dental and foundation in science students, and this improved awareness will ensure favorable attitudes toward cervical cancer vaccines or will attend regular screening programs. Awareness program must be held at regular intervals at different locations to enhance the knowledge dissemination of this common yet preventable genital malignancy of females. The IP collaboration and practices will help in reducing the disease burden of the society in future.
Comparing the outcome of monitored anaesthesia care and local anaesthesia for carpal tunnel syndrome surgery by neurosurgeons

Goh CH, Lau BL, Teong SY, Law WC, Tan CS, Vasu R, et al.

Med J Malaysia, 2019 12;74(6):499-503.
PMID: 31929475

INTRODUCTION: Carpal tunnel syndrome (CTS) is the commonest median nerve entrapment neuropathy of the hand, up to 90% of all nerve compression syndromes. The disease is often treated with conservative measures or surgery. The senior author initially intended to treat his own neurosurgical patients concurrently diagnosed with carpal tunnel syndrome in 2014, subsequently, he began to pick up more referrals from the primary healthcare group over the years. This has led to the setup of a peripheral and spine clinic to act as a hub of referrals.
OBJECTIVE: Department of Neurosurgery Sarawak aimed to evaluate the surgical outcome of carpal tunnel release done over five years.
METHODS: The carpal tunnel surgeries were done under local anaesthesia (LA) given by neurosurgeons (Bupivacaine 0.5% or Lignocaine 2%). Monitored anaesthesia care (MAC) was later introduced by our hospital neuroanaesthetist in the beginning of 2018 (Target-controlled infusion propofol and boluses of fentanyl). We looked into our first 17 cases and compared these to the two anaesthesia techniques (LA versus MAC + LA) in terms of patient's pain score based on visual analogue scale (VAS).
RESULTS: Result showed MAC provided excellent pain control during and immediately after the surgery. None experienced anaesthesia complications. There was no difference in pain control at post-operation one month. Both techniques had equal good clinical outcome during patients' clinic follow up.
CONCLUSION: Neurosurgeons provide alternative route for CTS patients to receive surgical treatment. Being a designated pain free hospital, anaesthetist collaboration in carpal tunnel surgery is an added value and improves patients overall experience and satisfaction.
Nitrogen-doped carbon quantum dots-decorated 2D graphitic carbon nitride as a promising photocatalyst for environmental remediation: A study on the importance of hybridization approach

Seng RX, Tan LL, Lee WPC, Ong WJ, Chai SP

J Environ Manage, 2020 Feb 01;255:109936.
PMID: 32063312 DOI: 10.1016/j.jenvman.2019.109936

Growing concerns of water pollution by dye pollutants from the textile industry has led to vast research interest to find green solutions to address this issue. In recent years, heterogeneous photocatalysis has harvested tremendous attention from researchers due to its powerful potential applications in tackling many important energy and environmental challenges at a global level. To fully utilise the broad spectrum of solar energy has been a common aim in the photocatalyst industry. This study focuses on the development of an efficient, highly thermal and chemical stable, environmentally friendly and metal-free graphitic carbon nitride (g-C3N4) to overcome the problem of fast charge recombination which hinders photocatalytic performances. Nitrogen-doped carbon quantum dots (NCQDs) known for its high electronic and optical functionality properties is believed to achieve photocatalytic enhancement by efficient charge separation through forming heterogeneous interfaces. Hence, the current work focuses on the hybridisation of NCQDs and g-C3N4 to produce a composite photocatalyst for methylene blue (MB) degradation under LED light irradiation. The optimal hybridisation method and the mass loading required for maximum attainable MB degradation were systematically investigated. The optimum photocatalyst, 1 wt% NCQD/g-C3N4 composite was shown to exhibit a 2.6-fold increase in photocatalytic activity over bare g-C3N4. Moreover, the optimum sample displayed excellent stability and durability after three consecutive degradation cycles, retaining 91.2% of its original efficiency. Scavenging tests were also performed where reactive species, photon-hole (h+) was identified as the primary active species initiating the pollutant degradation mechanism. The findings of this study successfully shed light on the hybridisation methods of NCQDs which improve existing g-C3N4 photocatalyst systems for environmental remediation by utilising solar energy.
Lactobacillus probiotics improved the gut microbiota profile of a Drosophila melanogaster Alzheimer's disease model and alleviated neurodegeneration in the eye

Tan FHP, Liu G, Lau SA, Jaafar MH, Park YH, Azzam G, et al.

Benef Microbes, 2020 Feb 19;11(1):79-89.
PMID: 32066253 DOI: 10.3920/BM2019.0086

Alzheimer's disease (AD) is a progressive disease and one of the most common forms of neurodegenerative disorders. Emerging evidence is supporting the use of various strategies that modulate gut microbiota to exert neurological and psychological changes. This includes the utilisation of probiotics as a natural and dietary intervention for brain health. Here, we showed the potential AD-reversal effects of Lactobacillus probiotics through feeding to our Drosophila melanogaster AD model. The administration of Lactobacillus strains was able to rescue the rough eye phenotype (REP) seen in AD-induced Drosophila, with a more prominent effect observed upon the administration of Lactobacillus plantarum DR7 (DR7). Furthermore, we analysed the gut microbiota of the AD-induced Drosophila and found elevated levels of Wolbachia. The administration of DR7 restored the gut microbiota diversity of AD-induced Drosophila with a significant reduction in Wolbachia's relative abundance, accompanied by an increase of Stenotrophomonas and Acetobacter. Through functional predictive analyses, Wolbachia was predicted to be positively correlated with neurodegenerative disorders, such as Parkinson's, Huntington's and Alzheimer's diseases, while Stenotrophomonas was negatively correlated with these neurodegenerative disorders. Altogether, our data exhibited DR7's ability to ameliorate the AD effects in our AD-induced Drosophila. Thus, we propose that Wolbachia be used as a potential biomarker for AD.
Genetic diversity and differentiation in the blackflies Simulium cheongi, Simulium jeffreyi and Simulium vanluni (Diptera: Simuliidae) in Peninsular Malaysia

Pavitra SP, Ya'cob Z, Tan TK, Lim YAL, Low VL

Acta Trop, 2020 May;205:105415.
PMID: 32088275 DOI: 10.1016/j.actatropica.2020.105415

The population genetic structures of S. vanluni, S. cheongi and S. jeffreyi were determined from mitochondria-encoded sequences of cytochrome c oxidase subunits I (COI) across different states in Peninsular Malaysia. High levels of genetic diversity and genetic differentiation were observed among three species. All three species revealed an intermediate level of gene flow among the populations. Negative values of Fu's Fs and low values of Raggedness index supported the hypothesis of population expansion in S. vanluni, S. cheongi and S. jeffreyi.
Fulltext Data set and model code on the optimal operating state of a negative emission polygeneration system

Aviso KB, Tan RR, Foo DCY, Lee JY, Ubando AT

Data Brief, 2020 Apr;29:105140.
PMID: 32083153 DOI: 10.1016/j.dib.2020.105140

This article contains the data set and model code for the negative emission polygeneration system described in Tan et al. (2019). The data was generated utilizing an optimization model implemented in LINGO 18.0 and includes information on the operating state of each process unit in the system. The maximum annual profit of the system was determined at different carbon footprint targets. The data set and model code can be utilized for further analysis on the interdependence between the process units of this polygeneration system, its operational and environmental performance, and the potential impact of integrating new process units into the network.
A New Plant Expression System for Producing Pharmaceutical Proteins

Abd-Aziz N, Tan BC, Rejab NA, Othman RY, Khalid N

Mol Biotechnol, 2020 Apr;62(4):240-251.
PMID: 32108286 DOI: 10.1007/s12033-020-00242-2

In the past decade, interest in the production of recombinant pharmaceutical proteins in plants has tremendously progressed because plants do not harbor mammalian viruses, are economically competitive, easily scalable, and capable of carrying out complex post-translational modifications required for recombinant pharmaceutical proteins. Mucuna bracteata is an essential perennial cover crop species widely planted as an underground cover in oil palm and rubber plantations. As a legume, they have high biomass, thrive in its habitat, and can fix nitrogen. Thus, M. bracteata is a cost-efficient crop that shows ideal characteristics as a platform for mass production of recombinant protein. In this study, we established a new platform for the transient production of a recombinant protein in M. bracteata via vacuum-assisted agro-infiltration. Five-week-old M. bracteata plants were vacuum infiltrated with Agrobacterium tumefaciens harboring a plasmid that encodes for an anti-toxoplasma immunoglobulin (IgG) under different parameters, including trifoliate leaf positional effects, days to harvest post-infiltration, and the Agrobacterium strain used. Our results showed that vacuum infiltration of M. bracteata plant with A. tumefaciens strain GV3101 produced the highest concentration of heterologous protein in its bottom trifoliate leaf at 2 days post-infiltration. The purified anti-toxoplasma IgG was then analyzed using Western blot and ELISA. It was demonstrated that, while structural heterogeneity existed in the purified anti-toxoplasma IgG from M. bracteata, its transient expression level was two-fold higher than the model platform, Nicotiana benthamiana. This study has laid the foundation towards establishing M. bracteata as a potential platform for the production of recombinant pharmaceutical protein.
Evaluating the risk of popliteal artery injury in the all-inside meniscus repair based on the location of posterior meniscal lesions

Al-Fayyadh MZM, Tan HCY, Hui TS, Ali MRBM, Min NW

J Orthop Surg (Hong Kong), 2019 2 21;27(1):2309499019828552.
PMID: 30782072 DOI: 10.1177/2309499019828552

The 'all-inside' meniscus repair is extremely useful technique in addressing tears at the far posterior horn of meniscus. However, this procedure may place the popliteal neurovascular bundle at risk of injury. The purpose of this study was to evaluate the risk of popliteal artery injury by the trajectory of anchor delivery instruments inserted through standard knee arthroscopic portals for the repair of the far posterior horn of meniscus tears. Standard arthroscopic portals were marked on five human cadaveric knees which were subsequently disarticulated. Axial photographs were taken after marking the 5 10, and 15 mm points from the meniscal root on the posterior horns of the menisci. The unsafe zones for meniscus repair at each of these points were identified on the photographs of knees by first drawing two lines from the edges of the popliteal artery and crossing at the respective points at the posterior horns. The points at which these lines meet a circular protractor applied to the center of each meniscus in the knee photograph were recorded as a range. The range signifies the unsafe zone for each respective point on the posterior horn of meniscus. The anterolateral arthroscopic portal fell within the unsafe zone of the 5 mm point on the posterior horn of lateral meniscus in three of the five knees and within the unsafe zone of the 10 mm point on the posterior horn of lateral meniscus in another two knees. A cautious approach should be practiced during the repair of tears located at these two points. None of the other points' unsafe zones (lateral 15 mm, medial 5 mm, 10 mm and 15 mm points) coincided with the ipsilateral portal sites. Level of evidence 5 (Human cadaveric study).
Starch granules as Pickering emulsifiers: Role of octenylsuccinylation and particle size

Li S, Li C, Yang Y, He X, Zhang B, Fu X, et al.

Food Chem, 2019 Jun 15;283:437-444.
PMID: 30722895 DOI: 10.1016/j.foodchem.2019.01.020

The present study aimed at investigating the effects of octenylsuccinylation and particle size on the emulsifying properties of starch granules as Pickering emulsifiers. Starch spherulites (1-5 μm), native rice starch (5-10 μm), waxy maize starch (10-20 μm) and waxy potato starch (20-30 μm) were modified with octenylsuccinic anhydride. Results showed that octenylsuccinylation caused a significant increase in the contact angle, and there was a weak positive linear correlation with the emulsifying capacity of the starch granules. After octenylsuccinylation, smaller particles of octenylsuccinate-starch granules exhibited better emulsifying properties with smaller droplet size and lower creaming index. Overall, both octenylsuccinylation and particle size have important effects on the emulsifying properties of starch granules as Pickering stabilizers. This study could be useful in the design and development of starch-based Pickering emulsifiers, and provide potential applications in the food and pharmaceutical industries.
Fulltext Optimal sizing and energy scheduling of isolated microgrid considering the battery lifetime degradation

Sufyan M, Abd Rahim N, Tan C, Muhammad MA, Sheikh Raihan SR

PLoS One, 2019;14(2):e0211642.
PMID: 30763331 DOI: 10.1371/journal.pone.0211642

The incessantly growing demand for electricity in today's world claims an efficient and reliable system of energy supply. Distributed energy resources such as diesel generators, wind energy and solar energy can be combined within a microgrid to provide energy to the consumers in a sustainable manner. In order to ensure more reliable and economical energy supply, battery storage system is integrated within the microgrid. In this article, operating cost of isolated microgrid is reduced by economic scheduling considering the optimal size of the battery. However, deep discharge shortens the lifetime of battery operation. Therefore, the real time battery operation cost is modeled considering the depth of discharge at each time interval. Moreover, the proposed economic scheduling with battery sizing is optimized using firefly algorithm (FA). The efficacy of FA is compared with other metaheuristic techniques in terms of performance measurement indices, which are cost of electricity and loss of power supply probability. The results show that the proposed technique reduces the cost of microgrid and attain optimal size of the battery.

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