Bio-mediated production and characterisation of magnetic nanoparticles using fruit peel extract

The overwhelming request for nanodevices and heat flow developments has led to consider magnetic Fe3O4 nanoparticles as a new dawn to the sophisticated nanotechnology in a sustainable manner. This research presented a facile production of Fe3O4 nanoparticles using co-precipitation method and the extract of Garcinia Mangostana fruit peel waste as a green stabilizer and capping agent. The X-ray powder diffraction (XRD) planes of the synthesized nanoparticles showed the formation of magnetite Fe3O4 nanoparticles with good crystallinity. Based on the image of field emission scanning electron microscope (FESEM), the diameter of the nanoparticles was estimated to be 69.14±2.87 nm as was coated by the extract. The Fe3O4 nanoparticles presented an acceptable magnetization value of 51.17 emu/g. From the analysis of Fourier-transform infrared spectroscopy (FTIR), the phenolic compounds and other functional groups of the extract had interactions with the Fe ions to successfully synthesize the nanoparticles. The green synthesized Fe3O4 nanofluids showed small hydrodynamic size of 145.80±3.14 and high zeta potential value of -30.5±1.82 mV. This study, thus, showed that the extract of Garcinia Mangostana fruit peel waste can serve as a bio-stabilizer and capping agent to enhance physiochemical properties and colloidal stability of the Fe3O4 nanofluids with an environmentally-friendly manner and low cost for modern applications

2D Janus Niobium Oxydihalide NbOXYXY: Multifunctional High-Mobility Piezoelectric Semiconductor for Electronics, Photonics and Sustainable Energy Applications

Two-dimensional (2D) niobium oxydihalide NbOI$_2$ has been recently demonstrated as an excellent in-plane piezoelectric and nonlinear optical materials. Here we show that Janus niobium oxydihalide, NbO$XY$ (X, Y = Cl, Br, I and X$\neq$Y), is a multifunctional anisotropic semiconductor family with exceptional piezoelectric, electronic, photocatalytic and optical properties. NbO$XY$ are stable and mechancially flexible monolayers with band gap around the visible light regime of $\sim 1.9$ eV. The anisotropic carrier mobility of NbO$XY$ lies in the range of $10^3 \sim 10^4$ cm$^2$V$^{-1}$s$^{-1}$, which represents some of the highest among 2D semiconductors of bandgap $\gtrsim 2$ eV. Inversion symmetry breaking in Janus NbO$XY$ generates sizable out-of-plane $d_{31}$ piezoelectric response while still retaining a strong in-plane piezoelectricity. Remarkably, NbO$XY$ exhibits an additional out-of-plane piezoelectric response, $d_{32}$ as large as 0.55 pm/V. G$_0$W$_0$-BSE calculation further reveals the strong linear optical dichroism of NbO$XY$ in the visible-to-ultraviolet regime. The optical absorption peaks with $14\sim18$ \% in the deep UV regime ($5\sim6$ eV), outperforming the vast majority of other 2D materials. The high carrier mobility, strong optical absorption, sizable built-in electric field and band alignment compatible with overall water splitting further suggest the strengths of NbO$XY$ in energy conversion application. We further propose a directional stress sensing device to demonstrate how the out-of-plane piezoelectricity can be harnessed for functional device applications. Our findings unveil NbO$XY$ as an exceptional multifunctional 2D semiconductor for flexible electronics, optoelectronics, UV photonics, piezoelectric and sustainable energy applications.Comment: 16 Pages, 7 Figures, 3 Table

Economic injury level of oil palm bunch moth, Tirathaba mundella walker for pest management recommendations in oil palm production

Oil palm bunch moth, Tirathaba mundella Walker is a notorious bunch feeding pest typically among oil palm aged 3-7 years old planted on peat. In order to manage the pest, an economic injury level (EIL) for the pest needs to be determined which could assist in decision-making if a control tactic is justified. In order to determine the EIL, the percentage of fertile oil palm fruitlets and oil to bunch content were determined for fruit bunches with different pest infestation severity. The severity was characterised based on the mean larvae present in fruit bunches and male inflorescences. The study found that the mean larvae count was positively correlated with the economic losses and number of parthenocarpic fruitlets. The overall oil extraction rate (OER) of moderate and severely infested fruit bunches was significantly reduced as compared to clean fruit bunches. Based on average crude palm oil (CPO) market price and production per hectare, an EIL for T. mundella was able to be estimated. This study suggested the EIL at 10% of oil palms per hectare moderately or severely infested. The finding of this study would benefit future pest management practice in oil palm plantation established on peatland

Effectiveness of insecticides rotation with different modes of action against oil palm bunch moth Tirathaba mundella (WALKER (Lepidoptera, Pyralidae)

Tirathaba mundella Walker has emerged as one of the most prominent bunch feeding pests in Sarawak peat oil palm estates. Insecticides application is inevitable to prevent economic loss. However, to protect insect pollinators which cohabitat with the pest and reduce the risk of resistance development among the pest to insecticides, rotation treatments with more than one pollinator-friendly insecticides is recommended. This paper examines the effectiveness of rotating several pollinator-friendly insecticides in controlling the pest. To assess the effectiveness of different rotation combination, a field study on a seven-year-old peat estate was carried out using several insecticides combinations and application intervals, then the level of infestation post-treatment was assessed. Significantly, the results showed that only four single rounds of insecticides application in a year would yield relatively better control than nine rounds of Bacillus thuringiensis applications. Overall, there was no significant difference in clean bunches percentages obtained between five rounds of treatment compared to only four rounds per year. The result strengthens our confidence that the optimum and most cost-effective approach for one-year protection against T. mundella was two rounds of 30.0 g active ingredient of chlorantraniliprole per ha rotated with two rounds of 25.0 g active ingredient of chromafenozide. The material cost was calculated as RM 351.20 per ha per year. The findings of this study would benefit future pest management practice in oil palm plantation established on peatland

Green synthesis of Fe3O4 nanoparticles stabilized by a Garcinia mangostana fruit peel extract for hyperthermia and anticancer activities

Fe3O4 nanoparticles (Fe3O4 NPs) with multiple functionalities are intriguing candidates for various biomedical applications. Materials and Methods: This study introduced a simple and green synthesis of Fe3O4 NPs using a low-cost stabilizer of plant waste extract rich in polyphenols content with a well-known antioxidant property as well as anticancer ability to eliminate colon cancer cells. Herein, Fe3O4 NPs were fabricated via a facile co-precipitation method using the crude extract of Garcinia mangostana fruit peel as a green stabilizer at different weight percentages (1, 2, 5, and 10 wt.%). The samples were analyzed for magnetic hyperthermia and then in vitro cytotoxicity assay was performed. Results: The XRD planes of the samples were corresponding to the standard magnetite Fe3O4 with high crystallinity. From TEM analysis, the green synthesized NPs were spherical with an average size of 13.42±1.58 nm and displayed diffraction rings of the Fe3O4 phase, which was in good agreement with the obtained XRD results. FESEM images showed that the extract covered the surface of the Fe3O4 NPs well. The magnetization values for the magnetite samples were ranging from 49.80 emu/g to 69.42 emu/g. FTIR analysis verified the functional groups of the extract compounds and their interactions with the NPs. Based on DLS results, the hydrodynamic sizes of the Fe3O4 nanofluids were below 177 nm. Furthermore, the nanofluids indicated the zeta potential values up to −34.92±1.26 mV and remained stable during four weeks of storage, showing that the extract favorably improved the colloidal stability of the Fe3O4 NPs. In the hyperthermia experiment, the magnetic nanofluids showed the acceptable specific absorption rate (SAR) values and thermosensitive performances under exposure of various alternating magnetic fields. From results of in vitro cytotoxicity assay, the killing effects of the synthesized samples against HCT116 colon cancer cells were mostly higher compared to those against CCD112 colon normal cells. Remarkably, the Fe3O4 NPs containing 10 wt.% of the extract showed a lower IC50 value (99.80 μg/mL) in HCT116 colon cancer cell line than in CCD112 colon normal cell line (140.80 μg/mL). Discussion: This research, therefore, introduced a new stabilizer of Garcinia mangostana fruit peel extract for the biosynthesis of Fe3O4 NPs with desirable physiochemical properties for potential magnetic hyperthermia and colon cancer treatment

Principal component analysis on meteorological data in UTM KL

The high usage of fossil fuel to produce energy for the increasing demand of energy has been the primary culprit behind global warming. Renewable energies such as solar energy can be a solution in preventing the situation from worsening. Solar energy can be harnessed using available system such as solar thermal cogeneration systems. However, for the system to function smoothly and continuously, knowledge on solar radiation’s intensity several minutes in advance are required. Though there exist various solar radiation forecast models, most of the existing models requires high computational time. In this research, principal component analysis were applied on the meteorological data collected in Universiti Teknologi Malaysia Kuala Lumpur to reduce the dimension of the data. Dominant factors obtained from the analysis is expected to be useful for the development of solar radiation forecast model

Life cycle of oil palm bunch moth, Tirathaba mundella walker (Lepidoptera: Pyralidae) reared under laboratory conditions on artificial diet

Tirathaba mundella Walker is an important pest in many oil palm plantations especially those established on peatland. The life cycle of T. mundella has not been described in detail despite its economic importance. This study aimed to describe the bionomic characteristics of T. mundella, rearing on an artificial diet, at 25 oC. The duration of a complete metamorphosis cycle of T. mundella was about 51.63 ± 3.80 days. The incubation period was the shortest (3.33 ± 0.80 days.), The most detrimental stage of the pest to oil palm is at larval stage, which took 33.90 ± 2.60 days before pupating. The pupal period took about 5 to 11 days with a mean ± SD period of 8.53 ± 1.48 days. The average of the adult’s longevity was about 6.05 ± 1.81 days. There is no statistical difference between the duration of male and female longevity. Adult male and female moths reared in captivity feeded with 10% sucrose solution would mate readily and produce fertile eggs. The mean preoviposition period were 4 days. Successful of rearing T. mundella using artificial diet under laboratory conditions promises laboratory assessment for pesticide development which is less tedious and time consuming than conventional field experiments

Prognostic Value of Leucocyte Telomere Length in Acute Myocardial Infarction

Introduction: Leucocyte telomere length (LTL) has been described as a marker of biological age, endothelial dysfunction and atherosclerosis. The association between LTL and clinical characteristics of Asian patients, and their outcomes following acute myocardial infarction (AMI) have been inconclusive. Objective: To investigate the relationship between LTL and developing AMI, the association of LTL with inpatient and 30-day mortality, and the comparison to LTL with established AMI risk scores in predicting these outcomes. Methodology: 100 patients aged 30-70 years admitted with an AMI to a tertiary referral center between May-Oct 2017 were enrolled; these were matched with 100 non-AMI ('healthy') controls for gender and age (+/- 1 year). Clinical data was obtained prospectively; inpatient and 30-day outcomes documented. LTL was reflected by a well described variable called a tis ratio (TSR). The TSR was measured at enrolment using a quantitative PCR-based methods (qPCR) and results blinded to the clinician

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely