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Eating Behaviour Predicts Weight Loss Six Months after Bariatric Surgery: A Longitudinal Study
No full textBariatric surgery is currently the most durable weight loss solution for patients with morbid obesity. The extent of weight loss achieved, however, is subject to variation due to various factors, including patients’ behaviour. In this study, we aimed to identify pre-and post-surgical predictors of weight loss following bariatric surgery. This prospective study included 57 participants who went through bariatric surgery (laparoscopic Roux-en-Y gastric bypass: n = 30; laparoscopic sleeve gastrectomy: n = 23; one anastomosis gastric bypass-mini gastric bypass: n = 4) in two tertiary referral hospitals. Consenting participants were assessed prior to surgery (T0 ), and three months (T1 ) and six months (T2 ) after surgery. The assessment included interview and anthropometric measurements. The interview was done with the aid of instruments, including the Hospital Anxiety and Depression Scale (HADS) for anxiety and depression screening and the Dutch Eating Behaviour Questionnaire (DEBQ) for eating behaviour assessment. Baseline comorbidity status was obtained from medical records. A Generalised Estimating Equation (GEE) was developed to determine predictors of weight loss. Participants in the study were mostly women (n = 37, 65%) with a mean age of 39.4 (SD = 10.01) years. The mean excess BMI loss (EBMIL) and total weight loss (TWL) at the sixth month was 63.31% and 23.83%, respectively. Anxiety, depression, and external eating scores reduced over time. Advancing age, high BMI, and higher scores for emotional and external eating emerged as significant negative predictors for TWL%. It can be concluded that the patients experienced substantial weight loss after surgery. Continuous monitoring of psychological well-being and eating behaviour are essential for optimal weight loss
Cognitive complaints and predictors of perceived cognitive dysfunction in adults with major depressive disorder: Findings from the Cognitive Dysfunction in Asians with Depression (CogDAD) study
No full textBackground: Several studies have described the presence of perceived cognitive dysfunction amongst Asian patients with major depressive disorder (MDD). To date, no study has been conducted investigating the predictors of perceived cognitive dysfunction amongst Asian MDD patients. Methods: This was a post-hoc analysis of the Cognitive Dysfunction in Asian patients with Depression (CogDAD) study. Descriptive statistics were used to describe the most common cognitive complaints by patients. Univariate and multivariate analyses were performed to determine variables associated with perceived cognitive dysfunction (Perceived Deficit Questionnaire-Depression, PDQ-D). Results: The CogDAD study population is comprised of MDD patients with mild-to-moderate depression (Patient Health Questionnaire 9-item [PHQ-9]: 11.3 ± 6.9) who reported perceived cognitive dysfunction (PDQ-D = 22.6 ± 16.2). The most common cognitive complaints were: mind drifting (42.3%), trouble making decision (39.6%) and trouble concentrating (38.0%). Predictors of perceived cognitive dysfunction were: being Southeast Asians (vs. Taiwanese) (p < 0.001), current episode longer than 8 weeks (vs. 1–8 weeks) (p < 0.05), the presence of disability (vs. no disability) (p < 0.05), younger age (p < 0.01), and higher PHQ-9 total scores (p < 0.001). Limitations: The causal relationship between predictive variables and PDQ-D could not be tested due to the cross-sectional nature of the study. Furthermore, a neuropsychological test was not included in the CogDAD study and use of concomitant medications, including anti-depressants, could have impacted patient's perceived cognitive ability. Conclusions: The present study results suggest a potential role for subjective cognitive assessment in patients with MDD who are young, with long durations of depression or severe depression
Hyper-parameters optimisation of deep CNN architecture for vehicle logo recognition
No full textThe training of deep convolutional neural network (CNN) for classification purposes is critically dependent on the expertise of hyper-parameters tuning. This study aims to minimise the user variability in training CNN by automatically searching and optimising the CNN architecture, particularly in the field of vehicle logo recognition system. For this purpose, the architecture and hyper-parameters of CNN were selected according to the implementation of the stochastic method of particle swarm optimisation on the training-testing data. After obtaining the optimised hyper-parameters, the CNN is fine-tuned and trained to ensure better network convergence and classification performance. In this study, a total of 14,950 vehicle logo images are divided into two independent training and testing sets. In addition, these images are segmented coarsely, thus the requirement of precise logo segmentation is obviated in this work. The learned features of the CNN were sufficiently discriminative to be classified using multiclass Softmax classifier. With implementation using a graphics processing unit (GPU), the computation time of the proposed method is acceptable for real-time application. The experimental results explicitly prove that the authors' approach outperforms most of the state-of-the-art methods, achieving an accuracy of 99.1% over 13 vehicle manufacturers
In vitro antidermatophytic activity and cytotoxicity of extracts derived from medicinal plants and marine algae
No full textObjectives: This study was conducted to evaluate the antidermatophytic activity of 48 extracts obtained from medicinal plants (Cibotium barometz, Melastoma malabathricum, Meuhlenbeckia platyclada, Rhapis excelsa, Syzygium myrtifolium, Vernonia amygdalina) and marine algae (Caulerpa sertularioides, Kappaphycus alvarezii) against Trichophyton rubrum and Trichophyton interdigitale (ATCC reference strains), and the cytotoxicity using African monkey kidney epithelial (Vero) cells. Active plant extracts were screened for the presence of phytochemicals and tested against clinical isolates of Trichophyton tonsurans. Methods: Six different extracts (hexane, chloroform, ethyl acetate, ethanol, methanol and water) were obtained from each plant or algae sample using sequential solvent extraction. The antidermatophytic activity for the extracts was assessed using a colourimetric broth microdilution method. The viability of Vero cells was measured by Neutral Red uptake assay. Results: All the extracts (except the water extracts of V. amygdalina, C. sertularioides and K. alvarezii) showed antidermatophytic activity against Trichophyton spp. The minimum fungicidal concentration (MFC) ranges for the plant extracts against T. rubrum and T. interdigitale are 0.0025–2.50 and 0.005–2.50 mg/mL, respectively. The algae extracts exhibited lower potency against both species, showing MFC ranges of 0.08–2.50 and 0.31–2.50 mg/mL, respectively. The ethanol and methanol extracts from the leaves of R. excelsa, and the methanol and water extracts from the leaves of S. myrtifolium were highly active (MFC 2.8) against reference strains of T. rubrum and T. interdigitale, and most of the clinical isolates of T. tonsurans. Phytochemical analysis indicates the presence of alkaloids, anthraquinones, flavonoids, saponins, tannins, phenolics and triterpenoids in the extracts. Conclusions: The medicinal plant extracts exhibited stronger antidermatophytic activity compared to the algae extracts. The leaves of R. excelsa and S. myrtifolium are potential sources of new antidermatophytic agents against Trichophyton spp
Activated carbon as back contact for HTM-free mixed cation perovskite solar cell
No full textCarbon materials have potential applications in perovskite solar cell because of their excellent electronic properties and low cost. In this paper, we report, for the first time, activated carbon as a back contact for hole transport layer-free mixed halide perovskite solar cells. The ability of activated carbon to form conducting chain-like structure when dispersed in a polymeric solution makes it a possible candidate for back contact. A composite of activated carbon and PEMA was optimized with varying concentration. Mixed cation was used as a perovskite absorber and was analysed for its structural and optical properties. The fabricated devices were studied for their electrical performance. They were also subjected to stability study and showed promising results
Are first year medical students ready for OSCE?
No full textObjective: This study aimed to assess First Year medical students' readiness for OSCE. Design: This is a retrospective study where secondary data comprising both quantitative and qualitative data, were analysed. Materials and Methods: Three cohorts of First Year medical students (n = 454) took a 5-station OSCE. Two categories of tasks were assessed. Category A assessed patient and doctor interaction while Category B assessed clinical skills. A student must be scored as satisfactory in at least four out of five stations for a pass in Category A and at least three out of five stations for a pass in Category B. A pass in both Categories A and B is required to pass the OSCE. For each cohort, overall passing percentage, as well as passing percentage for Category A and Category B of each station, was computed. Examiners' feedback on students' performance during OSCE for each station was examined. Feedback from students regarding the OSCE was also sought. Results: For Cohort 2013, Cohort 2014 and Cohort 2015, 174/179 (97.21%), 118/129 (91.47%) and 140/147 (95.24%) of students passed the OSCE respectively. Cohort 2013, Cohort 2014 and Cohort 2015 recorded mean percent pass of (95.31%, 88.83%), (89.15%, 83.10%) and (98.36%, 84.52%) for Category A and Category B respectively. Examiners' feedback was generally favourable. Feedback from students was mixed but constructive and generally encouraging. Conclusions: Based on students' performance in the OSCE as well as feedback from both examiners and students, First Year medical students appeared to be ready for OSCE assessment
Enhanced photocatalytic performance of ZnSe/PANI nanocomposites for degradation of organic and inorganic pollutants
No full textCurrent work presents a study about the effect of polyaniline (PANI) as an organic semiconductor on the photocatalytic performance of ZnSe nanoparticles (NPs). Pristine ZnSe NPs and ZnSe/PANI nanocomposites were synthesized by a simple and cost-effective co-precipitation method in the ambient conditions. X-ray diffraction (XRD), Raman, and Fourier-transform infrared spectroscopy (FTIR) results confirmed that, a heterojunction was created by ZnSe NPs and PANI composite. High-resolution transmission electron microscopy (HRTEM) image showed that the NPs were deposited by PANI completely and a core-shell structure was generated by ZnSe and PANI. Photoluminescence (PL) spectroscopy results showed the optical properties of the pristine ZnSe NPs and ZnSe/PANI nanocomposites were similar with lower defect emission intensity for the ZnSe/PANI nanocomposites. However, the PL and UV–Vis results revealed that, the PANI caused a decrease in band-gap value of the ZnSe/PANI nanocomposites in compared to the band-gap value of the pristine ZnSe NPs. In addition, X-ray photoelectron spectroscopy (XPS) results indicated that, the PANI caused a shift in the valance band (VB) and conduction band (CB) edges of ZnSe/PANI nanocomposites in compared with pristine ZnSe NPS. Finally, the photocatalytic performance of the products for removing of methylene blue (MB) and chromate ions was examined under a visible-light source irradiation. An enhancement photocatalytic performance for ZnSe/PANI nanocomposites in compared to the pristine ZnSe NPs was observed. Brunauer–Emmett–Teller (BET) results indicated that textural properties of the nanocomposites were decreased by PANI. According to the optical properties and band gap-value of the products a type-II heterojunction was created by band alignment of the ZnSe and PANI and such heterojunction was the most important factor for the enhancement photocatalytic performance of the ZnSe/PANI nanocomposites in compared to the photocatalytic activity of the pristine ZnSe NPs
Structural, electrochemical, and adsorption studies of Ni and Zn benzylimidazole coordination polymers with terephthalate linkers
No full textTwo coordination polymers, [Ni(bim)2(L1)(H2O)2]n (CP-1) and [Zn(bim)(L1)(Cl)]n (CP-2) (bim = 1-benzylimidazole, L1 = terephthalic acid), were synthesized and characterized by physicochemical and spectroscopic methods. The Ni(II) center in CP-1 is octahedral, while the Zn(II) center in CP-2 is tetrahedral. CP-1 and CP-2 were used to modify carbon paste electrodes to assess their effect on the electrochemical behavior of ferricyanide. The redox reactions of ferricyanide on both electrodes proved to be reversible and diffusion controlled, with ferricyanide diffusion coefficients for CP-1 and CP-2 of 1.88 × 105 and 3.44 × 105 cm2 s−1, respectively. These coordination polymers were also investigated for their adsorption behavior toward two dyes: Chicago sky blue and methylene blue. CP-1 and CP-2 both rapidly adsorbed the anionic Chicago sky blue dye by different intermolecular interactions; in contrast, the cationic methylene blue dye was adsorbed to a lesser extent. The adsorption of these CPs depends on the charge but not the size of the dye. Addition of methanolic potassium nitrate solution caused the release of the adsorbed dyes
The role of nutrient-related genes in understanding the saxitoxin production of Alexandrium minutum
Get PDFAlexandrium minutum is a saxitoxins-producring marine dinoflagellate that responsible for paralytic shellfish
poisoning (PSP). It is widely distributed in the tropical and temperate waters with various hydrographic regimes. The
physiological responses of this species to various macronutrients have been studied intensively, but little is known about the regulating mechanism of nutrient uptakes and their roles in saxitoxin production. The effect of varying levels of nitrogen and phosphorous nutrition on the transcriptional responses of a tropical ribotype of A. minutum was investigated in a laboratory setting. The nutrient-related genes, ammonium transporter (AmAmt1), nitrate transporter (AmNrt2), phosphate transporter (AmPiPT1), nitrate reductase (AmNas), glutamine synthetase (AmGSIII) and carbarmoyl phosphate synthase (AmCPSIII) were assembled from Sequence Read Archive (SRA) data set, and later used in the differential gene expression analyzed by qPCR. The results showed that, AmAmt1 was suppressed in excess ammonium-grown culture; conversely AmNrt2 and AmNas were induced. Gene expression of AmAmt1, AmNrt2, AmNas, AmGSIII, AmCPSII and AmPiPT1 was highly induced under P-deficient condition, suggesting that the cells are
scavenging to take up nutrients in the P-stress condition. Gene expression of AmCPSII was well correlated with the
toxin cell quota, suggesting the gene might involve in arginine metabolism and simultaneously increased the toxin
production. Nonetheless, AmGSIII expression might play a role in the stress adaption towards high toxic levels of
ammonium ambient by producing toxins as a counteracting response. The results of this study have provided better
insights into the eco-physiology of A. minutum in relation to the toxin production and its adaptive strategies in
unfavorable environments
Durable pressure filtration membranes based on polyaniline-polyimide P84 blends
No full textA pressure filtration membrane from conducting polymer polyaniline (PANI) is known to possess low mechanical strength and thermal stability. Therefore, it is believed that the properties of the membrane can be enhanced by blending PANI with a conventional polymer like polyimide (PI), which possesses high mechanical strength and thermal stability. A thermal analysis revealed that polymer chain of blend membranes started to break beyond the melting temperature of pure PANI membrane indicating that the addition of PI hindered the degradation of PANI and thus slowed down the decomposition process. Mechanical tests further showed that PANI/PI membrane had a tensile strength that was 60% higher than pure PANI membrane. Furthermore, the surface hydrophilicity and negativity of the blend membrane increased as it was doped in acid, thereby reflecting the exploitation of advantages of both polymers. Rejection at various molecular ranges of PEGs showed that PANI/PI membrane was initially in the ultrafiltration (UF) range, but later fell into the nanofiltration (NF) range when an acid dopant was introduced to the membrane. According to the long-term filtration performance, the PANI/PI membrane was able to sustain a rejection of up to 99% in Congo red solution with just a slight reduction in flux