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  1. Hoque A, Islam MT, Almutairi AF, Chowdhury MEH, Samsuzzaman M
    Sci Rep, 2020 Aug 04;10(1):13086.
    PMID: 32753600 DOI: 10.1038/s41598-020-69792-4
    This paper reports on a tunable transmission frequency characteristics-based metamaterial absorber of an X band sensing application with a fractional bandwidth. Tunable resonator metamaterial absorbers fabricated with dielectric surface have been the subject of growing attention of late. Absorbers possess electromagnetic properties and range modification capacity, and they have yet to be studied in detail. The proposed microstructure resonator inspired absorber with triple fractional band absorption consists of two balanced symmetrical vertical patches at the outer periphery and a tiny drop hole at two edges. Experimental verification depicted two absorption bands with single negative (SNG) characteristics for two resonances, but double negative (DNG) for single resonance frequency. The mechanism of sensing and absorption was analyzed using the transmission line principle with useful parameter analysis. Cotton, a hygroscopic fiber with moisture content, was chosen to characterize the proposed absorber for the X band application. The electrical properties of the cotton changed depending on the moisture absorption level. The simulation and the measured absorption approximately justified the result; the simulated absorption was above 90% (at 10.62, 11.64, and 12.8 GHz), although the steady level was 80%. The moisture content of the cotton (at different levels from 0 to 32.13%) was simulated, and the transmission resonance frequency changed its point in two significant ranges. However, comparing the two adopted measurement method and algorithm applied to the S parameter showed a closer variation between the two resonances (11.64 and 12.8 GHz) which signified that a much more accurate measurement of the cotton dielectric constant was possible up to a moisture content of 16.1%. However, certain unwanted changes were noted at 8.4-8.9 GHz and 10.6-12.4 GHz. The proposed triple-band absorber has potential applications in the X band sensing of moisture in capsules or tablet bottles.
  2. Abd Aziz AU, Abdul Wahab AH, Abdul Rahim RA, Abdul Kadir MR, Ramlee MH
    Injury, 2020 Nov;51(11):2474-2478.
    PMID: 32798038 DOI: 10.1016/j.injury.2020.08.001
    In an open fracture, the external fixator is one of the definitive treatment options as it could provide the initial stabilisation of the fractured bone. Limited literature discussing on the biomechanical stability between unilateral, hybrid and Ilizarov configurations, principally in treating a femoral fracture. Thus, this study aims to analyse the biomechanical stability of different external fixators via the finite element method (FEM). The present study portrays that different configurations of fixators possess different biomechanical stability, hence leading to different healing rates and complication risks. For the methodology, three-dimensional models of three different external fixators were reconstructed where axial loads were applied on the proximal end of the femur, simulating the stance phase. From the results, the unilateral configuration provides better stability compared to the hybrid and Ilizarov, where it displaced the least with an average percentage difference of 50% for the fixator's frame and 23% for the bone. The unilateral configuration also produced the least interfragmentary movement (0.48 mm) as compared to hybrid (0.62 mm) and Ilizarov (0.61 mm) configurations. Besides, the strain and stress of the unilateral configuration were superior in terms of stability compared to the other two configurations. As a conclusion, the unilateral configuration had the best biomechanical stability as it was able to assist the bone healing process as well as minimising the risk of pin tract infection while treating a femoral fracture.
  3. Nasir MSNM, Ishak MN, Abd Wahid FH, Asif JA, Mohamad I
    Medeni Med J, 2019;34(4):400-403.
    PMID: 32821468 DOI: 10.5222/MMJ.2019.44977
    Oral cyst is uncommon in the neonatal period. Depending on the size and site of occurrence, its symptoms may vary. If not diagnosed and managed expeditiously, these oral cysts may cause significant and potentially fatal morbidity and mortality. We report a successfully managed case of oral cyst in neonate that presented with huge tongue at birth and complaints of impending airway obstruction. She was referred for tracheostomy as intubation was impossible. We attempted needle aspiration and the airway successfully relieved without the need for tracheostomy.
  4. Sultan T, Cheah CW, Ibrahim NB, Asif MK, Vaithilingam RD
    J Dent, 2020 Oct;101:103455.
    PMID: 32828845 DOI: 10.1016/j.jdent.2020.103455
    OBJECTIVES: This clinical study assessed and compared the linear and volumetric changes of extraction sockets grafted with a combination of Platelet-Rich Fibrin (PRF) and Calcium Sulfate (CS) (PRF-CS), and extraction sockets grafted with a combination of PRF and xenograft (X) (PRF-X).

    METHODS: Five single maxillary premolar extraction sockets received PRF-CS grafts and five single maxillary premolar sockets received PRF-X grafts. Linear (horizontal and vertical) measurements were accomplished using Cone Beam Computed Tomography (CBCT) images and volumetric changes were assessed using MIMICS software. Soft tissue level changes were measured using Stonecast models. All measurements were recorded at baseline (before extraction) and at 5-months post-extraction.

    RESULTS: Significant reduction in vertical and horizontal dimensions were observed in both groups except for distal bone height (DBH = 0.44 ± 0.45 mm, p = 0.09) and palatal bone height (PBH = 0.39 ± 0.34 mm, p = 0.06) in PRF-X group. PRF-CS group demonstrated mean horizontal shrinkage of 1.27 ± 0.82 mm (p = 0.02), when compared with PRF-X group (1.40 ± 0.85 mm, p = 0.02). Vertical resorption for mesial bone height (MBH = 0.56 ± 0.25 mm, p = 0.008), buccal bone height (BBH = 1.62 ± 0.91 mm, p = 0.01) and palatal bone height (PBH = 1.39 ± 0.87 mm, p = 0.02) in PRF-CS group was more than resorption in PRF-X group (MBH = 0.28 ± 0.14 mm, p = 0.01, BBH = 0.63 ± 0.39 mm, p = 0.02 and PBH = 0.39 ± 0.34 mm, p = 0.06). Volumetric bone resorption was significant within both groups (PRF-CS = 168.33 ± 63.68 mm3, p = 0.004; PRF-X = 102.88 ± 32.93 mm3, p = 0.002), though not significant (p = 0.08) when compared between groups. In PRF-X group, the distal soft tissue level (DSH = 1.00 ± 0.50 mm, p = 0.03) demonstrated almost 2 times more reduction when compared with PRF-CS group (DSH = 1.00 ± 1.00 mm, 0.08). The reduction of the buccal soft tissue level was pronounced in PRF-CS group (BSH = 2.00 ± 2.00 mm, p = 0.06) when compared with PRF-X group (BSH = 1.00 ± 1.50 mm, p = 0.05).

    CONCLUSIONS: PRF-CS grafted sites showed no significant difference with PRF-X grafted sites in linear and volumetric dimensional changes and might show clinical benefits for socket augmentation. The study is officially registered with ClinicalTrials.gov Registration (NCT03851289).

  5. Asif MK, Ibrahim N, Sivarajan S, Heng Khiang Teh N, Chek Wey M
    Am J Orthod Dentofacial Orthop, 2020 Oct;158(4):579-586.e1.
    PMID: 32826123 DOI: 10.1016/j.ajodo.2019.09.022
    INTRODUCTION: The study aimed to investigate the effects of micro-osteoperforations (MOPs) on the mandibular bone volume/tissue volume (BV/TV) ratio changes and the rate of orthodontic tooth movement using cone-beam computed tomography images. Another objective was to evaluate the effects of MOP frequency intervals (4 weeks, 8 weeks, and 12 weeks) on the BV/TV ratio and rate of tooth movement.

    METHODS: In 24 participants, 140-200 g of force was applied for mandibular canine retraction. Three MOPs were made according to the scheduled intervals of the 3 different groups: group 1 (MOP 4 weeks), group 2 (MOP 8 weeks), and group 3 (MOP 12 weeks) directly at the mandibular buccal cortical bone of extracted first premolars sites. Cone-beam computed tomography scans were obtained at the 12th week after MOP application. Computed tomography Analyzer software (version 1.11.0.0; Skyscan, Kontich, Belgium) was used to compute the trabecular alveolar BV/TV ratio.

    RESULTS: A significant difference was observed in the rate of canine movement between control and MOP. Paired t test analysis showed a significant difference (P = 0.001) in the mean BV/TV ratio between control and MOP sides in all the frequency intervals groups. However, the difference was significant only in group 1 (P = 0.014). A strong negative correlation (r = -0.86) was observed between the rate of canine tooth movement and the BV/TV ratio at the MOP side for group 1 and all frequency intervals together (r = -0.42).

    CONCLUSIONS: The rate of orthodontic tooth movement can be accelerated by the MOP technique with frequently repeated MOPs throughout the treatment.

  6. Girei SH, Lim HN, Ahmad MZ, Mahdi MA, Md Zain AR, Yaacob MH
    Sensors (Basel), 2020 Aug 21;20(17).
    PMID: 32825539 DOI: 10.3390/s20174713
    The need for environmental protection and water pollution control has led to the development of different sensors for determining many kinds of pollutants in water. Ammonia nitrogen presence is an important indicator of water quality in environmental monitoring applications. In this paper, a high sensitivity sensor for monitoring ammonia nitrogen concentration in water using a tapered microfiber interferometer (MFI) as a sensor platform and a broad supercontinuum laser as the light source is realized. The MFI is fabricated to the waist diameter of 8 µm producing a strong interference pattern due to the coupling of the fundamental mode with the cladding mode. The MFI sensor is investigated for a low concentration of ammonia nitrogen in water in the wide wavelength range from 1500-1800 nm with a high-power signal provided by the supercontinuum source. The broad source allows optical sensing characteristics of the MFI to be evaluated at four different wavelengths (1505, 1605, 1705, and 1785 nm) upon exposure towards various ammonia nitrogen concentrations. The highest sensitivity of 0.099 nm/ppm that indicates the wavelength shift is observed at 1785 nm operating wavelength. The response is linear in the ammonia nitrogen range of 5-30 ppm with the best measurement resolution calculated to be 0.5 ppm. The low concentration ammonia nitrogen detected by the MFI in the unique infrared region reveals the potential application of this optical fiber-based sensor for rivers and drinking water monitoring.
  7. Raza SA, Qureshi MA, Ahmed M, Qaiser S, Ali R, Ahmed F
    Environ Sci Pollut Res Int, 2021 Jan;28(2):1426-1442.
    PMID: 32840747 DOI: 10.1007/s11356-020-10179-3
    The study aims to analyze two objectives: first is to explore the non-linear relationship between tourism development, economic growth, urbanization, and environmental degradation, and also to analyze the threshold level of the contribution of tourism development on environmental degradation in top tourist arrival destinations. We applied the newly proposed econometric method panel smooth transition regression (PSTR) framework with two regimes on yearly panel data from 1995 to 2017. Findings suggest that the relationship between tourism development and environmental degradation is non-linear and regime dependent. Furthermore, the findings indicated that the relationship above the threshold level is negative and significant, while below the threshold, tourism development is positive and significant effect on environmental degradation. Tourism development and environmental degradation also exhibit the inverted U-shape relationship meaning that at a particular point, increase in tourism development increases in environmental degradation but after a particular point, increase in tourism development decreases the environmental degradation. The economic growth and urbanization also portray a non-linear and regime-dependent relationship with environmental degradation. The study assists policies and empirical information.
  8. Hossain MAM, Uddin SMK, Sultana S, Wahab YA, Sagadevan S, Johan MR, et al.
    Crit Rev Food Sci Nutr, 2022;62(2):285-310.
    PMID: 32914638 DOI: 10.1080/10408398.2020.1814691
    Meat and meat products are widely consumed worldwide as a source of high-quality proteins, essential amino acids, vitamins, and necessary minerals. The acceptability of Halal and Kosher meat products relies not only on the species origin but also on the manner of slaughtering of animals. Both Islam and Judaism have their own dietary laws in their holy books regarding acceptance and forbiddance of dietary items particularly meat and meat products. They also include many strictures to follow for ritual cleanliness of foods. Since the authenticity of Halal and Kosher food created increased concerns among consumers, the integrity of Halal and Kosher meat and meat products must be assured so that consumers can be accomplished with the originality of products. There is an increasing demand for reliable and sensitive techniques for the authentication of various Halal and Kosher meat products. This up-to-date review intends to provide an updated and extensive overview critically on the present situation, progress, and challenges of analytical techniques to authenticate animal species in meat items. It also addresses slaughtering procedure with brief discussion on Halal and Kosher laws with a view to creating consumer awareness against fraudulent practices. The available methods are schematically presented, and their salient features are comparatively elucidated in tables. Potential future technologies are predicted, and probable challenges are summarized. Overall, the present review article possesses substantial merits to be served as a reference guide in the field of academia and industry for the preparation/processing and identification of Halal and Kosher meat and meat products as well as may act as a platform to help improve existing authentication methods.
  9. Ng CL, Reaz MBI, Crespo ML, Cicuttin A, Chowdhury MEH
    Sci Rep, 2020 09 10;10(1):14891.
    PMID: 32913303 DOI: 10.1038/s41598-020-71709-0
    A capacitive electromyography (cEMG) biomedical sensor measures the EMG signal from human body through capacitive coupling methodology. It has the flexibility to be insulated by different types of materials. Each type of insulator will yield a unique skin-electrode capacitance which determine the performance of a cEMG biomedical sensor. Most of the insulator being explored are solid and non-breathable which cause perspiration in a long-term EMG measurement process. This research aims to explore the porous medical bandages such as micropore, gauze, and crepe bandage to be used as an insulator of a cEMG biomedical sensor. These materials are breathable and hypoallergenic. Their unique properties and characteristics have been reviewed respectively. A 50 Hz digital notch filter was developed and implemented in the EMG measurement system design to further enhance the performance of these porous medical bandage insulated cEMG biomedical sensors. A series of experimental verifications such as noise floor characterization, EMG signals measurement, and performance correlation were done on all these sensors. The micropore insulated cEMG biomedical sensor yielded the lowest noise floor amplitude of 2.44 mV and achieved the highest correlation coefficient result in comparison with the EMG signals captured by the conventional wet contact electrode.
  10. Kandasami P, Yita T, Chi XS, Chern WK, Muhammad Naim R, Afifah Afiah MD, et al.
    Med J Malaysia, 2020 09;75(5):467-471.
    PMID: 32918411
    INTRODUCTION: Patients undergoing emergency general surgery (EGS) are at risk for death and complications. Information on the burden of EGS is critical for developing strategies to improve the outcomes.

    METHODS: In this retrospective cohort study, medical records of all general surgical operations in a public hospital were reviewed for the period 1st January 2017 to 31st December 2017. Data on patient demographics, operative workload, case mix, time of surgery and outcomes were analysed.

    RESULTS: Of the 2960 general surgical operations that were performed in 2017, 1720 (58.1%) of the procedures were performed as emergencies. The mean age for the patients undergoing emergency general surgical procedures was 37.9 years (Standard Deviation, ±21.0), with male preponderance (57.5%). Appendicitis was the most frequent diagnosis for the emergency procedures (43%) followed by infections of the skin and soft tissues (31.6%). Disorders of the colon and rectum ranked as the third most common condition, accounting for 6.7% of the emergency procedures. Majority of emergency surgery (59.3%) took place after office hours and on weekends. Post-operative deaths and admissions to critical care facilities increased during EGS when compared to elective surgery, p<0.01.

    CONCLUSIONS: EGS constitutes a major part of the workload of general surgeons and it is associated significant risk for death and post-operative complications. The burden of EGS must be recognised and patient care systems must evolve to make surgery safe and efficient.

  11. Hasan SS, Kow CS, Hadi MA, Zaidi STR, Merchant HA
    Am J Cardiovasc Drugs, 2020 Dec;20(6):571-590.
    PMID: 32918209 DOI: 10.1007/s40256-020-00439-5
    INTRODUCTION: The use of renin-angiotensin system (RAS) inhibitors, including angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), was alleged to cause a more severe course of novel coronavirus disease 2019 (COVID-19).

    METHODS: We systematically reviewed the published studies to assess the association of RAS inhibitors with mortality as well as disease severity in COVID-19 patients. A systematic literature search was performed to retrieve relevant original studies investigating mortality and severity (severe/critical disease) in COVID-19 patients with and without exposure to RAS inhibitors.

    RESULTS: A total of 59 original studies were included for qualitative synthesis. Twenty-four studies that reported adjusted effect sizes (24 studies reported mortality outcomes and 16 studies reported disease severity outcomes), conducted in RAS inhibitor-exposed and unexposed groups, were pooled in random-effects models to estimate overall risk. Quality assessment of studies revealed that most of the studies included were of fair quality. The use of an ACEI/ARB in COVID-19 patients was significantly associated with lower odds (odds ratio [OR] = 0.73, 95% confidence interval [CI] 0.56-0.95; n = 18,749) or hazard (hazard ratio [HR] = 0.75, 95% CI 0.60-0.95; n = 26,598) of mortality compared with non-use of ACEI/ARB. However, the use of an ACEI/ARB was non-significantly associated with lower odds (OR = 0.91, 95% CI 0.75-1.10; n = 7446) or hazard (HR = 0.73, 95% CI 0.33-1.66; n = 6325) of developing severe/critical disease compared with non-use of an ACEI/ARB.

    DISCUSSION: Since there was no increased risk of harm, the use of RAS inhibitors for hypertension and other established clinical indications can be maintained in COVID-19 patients.

  12. Mohiuddin SG, Aziz S, Iqbal MZ, Naqvi AA, Ahmed R, Mahmoud MA, et al.
    J Pharm Bioallied Sci, 2020 01 29;12(1):57-63.
    PMID: 32801601 DOI: 10.4103/jpbs.JPBS_182_19
    Purpose: The demand of complementary and alternative medicine (CAM) has increased drastically over the past few decades. The perceptions about CAMs among general population are positive. However, the literature highlights that effectiveness and acceptance of alternative therapies among the general population is still a subject of debate.

    Materials and Methods: This is a cross-sectional study and the response along with demographic details was collected through a validated questionnaire; the results were analyzed by using a validated data collection tool. The results were concluded based on good, moderate, and poor responses, which were evaluated through data analysis by using the Statistical Package for the Social Sciences software version 20.0., SPSS Inc., Chicago, III, USA. A value of P < 0.05 was considered statistically significant.

    Results: In total, 182 (44.4%) of male and 228 (55.6%) of female respondents were selected for this study. Studies showed that a greater knowledge level was observed among female respondents (15.55 ± 2.7, P < 0.001). The selected Chinese population had relatively good knowledge (i.e., 15.63, P = 0.006). People practicing Buddhism had also good knowledge. Rural population had lesser family income and showed a good practice pattern and understanding (P = 0.006). The positive attitude was identified among women ( P < 0.001) with a mean score of 15.55 ± 2.7. Postgraduate participants were found to have diverse results with SD ± 6.23, and 77.1% had a good attitude. A statistically significant association was observed between religion and attitude of respondents (P < 0.001).

    Conclusion: Although a better practice was noticed in Malaysian population, more awareness is required and knowledge should be disseminated among the population to improve the overall health and quality of life in Malaysia.

  13. Kai Jun T, Suhana AR, Avatar Singh MS, Kadar Shiraz Qamil MA, Mawaddah A
    Iran J Med Sci, 2020 Jul;45(4):316-317.
    PMID: 32801423 DOI: 10.30476/ijms.2020.81956.0
  14. Ong SL, Bajuri MY, Abdul Suki MH, Nadira F, Zamri KS
    Cureus, 2020 Jul 29;12(7):e9451.
    PMID: 32864272 DOI: 10.7759/cureus.9451
    Hypertrophic scar formation is a major clinical problem that results in both cosmetic issues and functional loss. The management of a hypertrophic scar varies according to the severity of the sequelae from the scar. We describe a method of treatment in a patient who had a history of multiple debridements due to snake bite resulting in severe contracture of the fourth toe complicated with a hypertrophic scar.
  15. Walayat K, Ahmad M, Rasul A, Aslam S, Anjum MN, Sultan S, et al.
    Pak J Pharm Sci, 2020 Mar;33(2(Supplementary)):855-860.
    PMID: 32863262
    The drug resistance phenomenon in microbes is resulting in the ineffectiveness of available drugs to treat the infections. Thus, there is a continued need to discover new molecules to combat the drug resistance phenomenon. Norfloxacin is a fluoroquinolone antibiotic that is used for the treatment of urinary tract infections. In this research work, norfloxacin is structurally modified by hybridizing with a range of substituted acetohydrazidic moieties through a multistep reaction. The first step involves the coupling of norfloxacin 1 with methyl chloroacetate followed by the treatment with hydrazine hydrate to result in corresponding acetohydrazide 3. A range of substituted benzaldehydes were reacted with the acetohydrazide to form the targeted series of norfloxacin derivatives 4a-i. The final compounds were screened for antimicrobial activity. Among the tested compounds, 4c, 4d, 4e and 4f displayed better antifungal activity against F.avenaceum, while compound 4c and 4e were active against F. bubigeum.
  16. Iqbal SZ, Usman S, Razis AFA, Basheir Ali N, Saif T, Asi MR
    Int J Environ Res Public Health, 2020 Aug 03;17(15).
    PMID: 32756472 DOI: 10.3390/ijerph17155602
    The main goal of the present research was to explore the seasonal variation of deoxynivalenol (DON) in wheat, corn, and their products, collected during 2018-2019. Samples of 449 of wheat and products and 270 samples of corn and their products were examined using reverse-phase liquid chromatography with a UV detector. The findings of the present work showed that 104 (44.8%) samples of wheat and products from the summer season, and 91 (41.9%) samples from winter season were contaminated with DON (concentration limit of detections (LOD) to 2145 µg/kg and LOD to 2050 µg/kg), from summer and winter seasons, respectively. In corn and products, 87 (61.2%) samples from summer and 57 (44.5%) samples from winter season were polluted with DON with levels ranging from LOD to 2967 µg/kg and LOD to 2490 µg/kg, from the summer and winter season, respectively. The highest dietary intake of DON was determined in wheat flour 8.84 µg/kg body weight/day from the summer season, and 7.21 µg/kg body weight/day from the winter season. The findings of the work argued the need to implement stringent guidelines and create awareness among farmers, stakeholders, and traders of the harmful effect of DON. It is mostly observed that cereal crops are transported and stockpiled in jute bags, which may absorb moisture from the environment and produce favorable conditions for fungal growth. Therefore, these crops must store in polyethylene bags during transportation and storage, and moisture should be controlled. It is highly desirable to use those varieties that are more resistant to fungi attack. Humidity and moisture levels need to be controlled during storage and transportation.
  17. Vohra MS, Ahmad B, Serpell CJ, Parhar IS, Wong EH
    Differentiation, 2020 08 23;115:62-84.
    PMID: 32891960 DOI: 10.1016/j.diff.2020.08.003
    Adipogenesis has been extensively studied using in vitro models of cellular differentiation, enabling long-term regulation of fat cell metabolism in human adipose tissue (AT) material. Many studies promote the idea that manipulation of this process could potentially reduce the prevalence of obesity and its related diseases. It has now become essential to understand the molecular basis of fat cell development to tackle this pandemic disease, by identifying therapeutic targets and new biomarkers. This review explores murine cell models and their applications for study of the adipogenic differentiation process in vitro. We focus on the benefits and limitations of different cell line models to aid in interpreting data and selecting a good cell line model for successful understanding of adipose biology.
  18. Woon KL, Mustapa SAS, Mohd Jamel NS, Lee VS, Zakaria MZ, Ariffin A
    Chemphyschem, 2020 Sep 17.
    PMID: 32940952 DOI: 10.1002/cphc.202000612
    Material designs that use donor and acceptor units are often found in organic optoelectronic devices. Molecular level insight into the interactions between donors and acceptors are crucial for understanding how such interactions can modify the optical properties of the organic optoelectronic materials. In this paper, tris(4-(tert-butyl)phenyl)amine (pTPA) was synthesized as a donor in order to compare with unmodified triphenylamine (TPA) in a donor-acceptor system by having 2,4,6-triphenyl-1,3,5-triazine (TRZ) as an acceptor. Dimerization of donors and acceptors occurred in solvent when the concentration of solute is high. At 0 K, using a polarizable continuum model, the nitrogen atom of TPA is found to stack on top of the center of triazine of TRZ, whereas such alignment is offset in pTPA and TRZ. We attributed such alignment in TPA-TRZ as the result of attractive interactions between partial localization of 2pz electrons at the nitrogen atom of TPA and the π deficiency of triazine in TPA-TRZ. By taking into account random motions of the solvent effect at 300 K in quantum molecular dynamics and classical molecular dynamics simulations to interpret the marked difference in emission spectra between TPA-TRZ and pTPA-TRZ, it was revealed that the attractive interaction between pTPA and TRZ in toluene is weaker than TPA and TRZ. Because of the weaker attractive interaction between pTPA and TRZ in toluene, the dimers adopted numerous ground state conformations resulting in broad emission bands superimposed with multiple small Gaussian peaks. This is in contrast to TPA-TRZ which has only one dominant dimer conformation. This study demonstrates that the strength of intermolecular interactions between donors and acceptors should be taken into consideration in designing supramolecular structures.
  19. Haditiar Y, Putri MR, Ismail N, Muchlisin ZA, Ikhwan M, Rizal S
    Heliyon, 2020 Sep;6(9):e04828.
    PMID: 32939416 DOI: 10.1016/j.heliyon.2020.e04828
    Malacca Strait (MS) has an important role and potential for many countries. It is a major transportation route for oil and commodities across continents. In addition, various activities such as shipping, fishing, aquaculture, oil drilling, and energy are also carried out in MS. Tides strongly affect the MS environment so that it becomes a major parameter in MS management. This paper is the first study, which presents MS tidal hydrodynamics based on a baroclinic and nonhydrostatic approach. Tidal hydrodynamics in MS and the surrounding waters were assessed using tidal forces, temperature, salinity, and density. This study analyzes the amplitude, phase, current ellipses, and semi-major axis of the tides. These variables are obtained from the simulation results of the three-dimensional numerical models of M2 tides and combined tides (M2, S2, N2, K1, and O1) with nonhydrostatic models. Then the results obtained are verified by observation data. Amplitude and phase of the tidal wave in MS originate from two directions, namely the northern part of MS (Andaman Sea) and the South China Sea (SCS). Tides from the north of MS propagate into the MS, while tides from the SCS travel to Singapore Waters (SW) and the south of MS. This causes a complex residual flow in SW and shoaling in the middle of MS. Shoaling in the middle of MS is characterized by a large amplitude and semi-major, as in B. Siapiapi. The results of this analysis show that tidal waves are dominated by semidiurnal types rather than diurnal types. The M2 current ellipse has dominantly anticlockwise rotation along the west of the MS, while along the east of MS, it has generally a clockwise rotation.
  20. Taufik M, Shahrul I, Mohd Nordin AR, Ikhwanuddin M, Abol-Munafi AB
    Trop Life Sci Res, 2020 Jul;31(2):79-105.
    PMID: 32922670 DOI: 10.21315/tlsr2020.31.2.5
    Nutritional quality of the hepatopancreas and gonads of orange portunid mud crab, Scylla olivacea was evaluated for each gender under four treatment of different water velocities (0, 20, 40 and 60 cm s-1), in terms of nutrient reserve and nutrient for reproduction. About 56 crabs were used in this study in which fatty acids composition was analysed using gas chromatography mass-spectrometry (GC-MS). For hepatopancreas analysis, monounsaturated fatty acids (MUFAs) were present in the highest fatty acids concentration, followed by polyunsaturated fatty acids (PUFAs) and, saturated fatty acids (SFAs). However, long-chain polyunsaturated fatty acids (LC-PUFAs) were displayed in low concentration in the hepatopancreas. Total fatty acid (TFAs) composition was significantly higher at moderate velocity of 20 cm s-1 compared to other water velocity treatments. For gonad analysis, 20 cm s-1 showed the highest TFA concentration of 93.34 mg g-1 while, the lowest concentration of 3.90 mg g-1 occurred at 0 cm s-1. There were significant differences in male and female crab's fatty acids contents of gonads at all flow velocities challenged (p < 0.05). PUFAs and MUFAs were dominant while, SFAs were observed at low concentration. This study revealed that, concentration of PUFAs increased as gonad maturation increased. The decreasing concentration of hepatopancreas fatty acids over the culture period indicated that nutrient was shifted from the hepatopancreas, to be used as energy reserved to gonads for further growth of eggs and offspring. The linkages between water flow strength, hepatopancreas, and gonad fatty acids concentrations, is fundamental knowledge useful in establishing efficient habitat velocities selection which will improve aquaculture production of mud crabs with high quality broodstock.
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