Novel hydroxyapatite-based bio-ceramic hollow fiber membrane derived from waste cow bone for textile wastewater treatment

Industrial textile wastewater is toxic due to the presence of recalcitrant color pigments and poisonous heavy metals. In this study, the hydroxyapatite (HAp)-based bio-ceramic hollow fiber membranes (h-bio-CHFM) were developed via the combined phase inversion and sintering technique. It was found that the properties of the developed h-bio-CHFMs were greatly affected by the HAp content of the ceramic suspension, and sintering temperature. The h-bio-CHFM with the sintering temperature of 1200 degrees C exhibited the long rod-shaped HAp particles and the smallest pore size (0.013 mu m). High removals of color (99.9%), COD (80.1%), turbidity (99.4%) and conductivity (30.1%) were achieved using the h-bio-CHFM sintered at 1200 degrees C with stable high flux of 88.3 L/m(2)h. Remarkably, the h-bio-CHFM sintered in the temperature range of 1000-1200 degrees C also demonstrated excellent adsorption ability towards heavy metals with 100% removals. The results of this study show the potential of the h-bio-CHFM for the efficient industrial textile wastewater treatment applications

Effects of temperature on rice husk silica ash additive for fouling mitigation by polysulfone-RHS ash mixed matrix composite membranes

Abstract: It has been found that the preparation of green silica based on agricultural crops preserves environmental sustainability. In this study, rice husk silica (RHS) ash was prepared by burning rice husk (RH) at different temperatures (400 and 1200 °C). Both types of green RHS ash additives were blended with polysulfone dope, after which membranes were fabricated via phase inversion. The RHS ash that was synthesised at 400 °C (RHS400) had an amorphous structure with strong hydrophilic properties, while the composite membrane containing 3 wt% of RHS400 (A3 membrane) achieved the optimum properties of a dense top, an extended sub-layer of continuous smaller finger-like pores and a bottom layer of macrovoids. A satisfactory mean surface roughness, average pore size (1.90 ± 9.50 × 10−2 µm), porosity (40.66 ± 2.03%) and tensile strength (3.27 ± 0.16 MPa) were also obtained. The contact angle (52.5° ± 3.6°) further proved that this membrane was hydrophilic. The elemental and thermal analyses confirmed the presence of Si and O, which correlated with the 12% residual that was contributed by the silica inside the membrane. The optimum properties of the A3 membrane were an increased PWF (154.04 ± 7.70 L m−2 h−1) with the highest rejection of HA (96.00 ± 4.80%) and a fouling mitigation with the lowest internal resistance (6.79 ± 0.34 × 1012 m−1). Graphic abstract: [Figure not available: see fulltext.

Comparison of planned and measured rectal dose in vivo during high dose rate Cobalt-60 brachytheraphy of cervical cancer

Cobalt-60 (Co-60) is a relatively new source for the application of high-dose rate (HDR) brachytherapy. Radiation dose to the rectum is often a limiting factor in achieving the full prescribed dose to the target during brachytherapy of cervical cancer. The aim of this study was to measure radiation doses to the rectum in-vivo during HDR Co-60 brachytherapy. A total of eleven HDR brachytherapy treatments of cervical cancer were recruited in this study. A series of diodes incorporated in a rectal probe was inserted into the patient's rectum during each brachytherapy procedure. Real-time measured rectal doses were compared to calculated doses by the treatment planning system (TPS). The differences between calculated and measured dose ranged from 8.5% to 41.2%. This corresponds to absolute dose differences ranging from 0.3 Gy to 1.5 Gy. A linear relationship was observed between calculated and measured doses with linear regression R2 value of 0.88, indicating close association between the measured and calculated doses. In general, absorbed doses for the rectum as calculated by TPS were observed to be higher than the doses measured using the diode probe. In-vivo dosimetry is an important quality assurance method for HDR brachytherapy of cervical cancer. It provides information that can contribute to the reduction of errors and discrepancies in dose delivery. Our study has shown that in-vivo dosimetry is feasible and can be performed to estimate the dose to the rectum during HDR brachytherapy using Co-60

Evaluation of rectal dose discrepancies between planned and in vivo dosimetry using MOSkin detector and PTW 9112 semiconductor probe during \u3csup\u3e60\u3c/sup\u3eCo HDR CT-based intracavitary cervix brachytherapy

2019 Associazione Italiana di Fisica Medica Purpose: Dose to the rectum during brachytherapy treatment may differ from an approved treatment plan which can be quantified with in vivo dosimetry (IVD). This study compares the planned with in vivo doses measured with MOSkin and PTW 9112 rectal probe in patients undergoing CT based HDR cervical brachytherapy with Co-60 source. Methods: Dose measurement of a standard pear-shaped plan carried out in phantom to verify the MOSkin dose measurement accuracy. With MOSkin attached to the third diode, RP3 of the PTW 9112, both detectors were inserted into patients\u27 rectum. The RP3 and MOSkin measured doses in 18 sessions as well as the maximum measured doses from PTW 9112, RPmax in 48 sessions were compared to the planned doses. Results: Percentage dose differences ΔD (%) in phantom study for two MOSkin found to be 2.22 ± 0.07% and 2.5 ± 0.07%. IVD of 18 sessions resulted in ΔD(%) of −16.3% to 14.9% with MOSkin and ΔD(%) of −35.7% to −2.1% with RP3. In 48 sessions, RPmax recorded ΔD(%) of −37.1% to 11.0%. MOSkin_measured doses were higher in 44.4% (8/18) sessions, while RP3_measured were lower than planned doses in all sessions. RPmax_measured were lower in 87.5% of applications (42/47). Conclusions: The delivered doses proven to deviate from planned doses due to unavoidable shift between imaging and treatment as measured with MOSkin and PTW 9112 detectors. The integration of MOSkin on commercial PTW 9112 surface found to be feasible for rectal dose IVD during cervical HDR ICBT

Dosimetric impact of applicator displacement during high dose rate (HDR) Cobalt-60 brachytherapy for cervical cancer: A planning study

We investigated the dosimetric impact of applicator displacement on dose specification during high dose rate (HDR) Cobalt-60 (Co-60) brachytherapy for cervical cancer through a planning study. Eighteen randomly selected HDR full insertion plans were restrospectively studied. The tandem and ovoids were virtually shifted translationally and rotationally in the x-, y- and z-axis directions on the treatment planning system. Doses to reference points and volumes of interest in the plans with shifted applicators were compared with the original plans. The impact of dose displacement on 2D (point-based) and 3D (volume-based) treatment planning techniques was also assessed. A ±2 mm translational y-axis applicator shift and ±4° rotational x-axis applicator shift resulted in dosimetric changes of more than 5% to organs at risk (OAR) reference points. Changes to the maximum doses to 2cc of the organ (D2cc) in 3D planning were statistically significant and higher than the reference points in 2D planning for both the rectum and bladder (p<0.05). Rectal D2cc was observed to be the most sensitive to applicator displacement among all dose metrics. Applicator displacement that is greater than ±2mm translational y-axis and ±4° rotational x-axis resulted in significant dose changes to the OAR. Thus, steps must be taken to minimize the possibility of applicator displacement during brachytherapy

Comparison of planned and measured rectal dose in-vivo during high dose rate Cobalt-60 brachytherapy of cervical cancer

Cobalt-60 (Co-60) is a relatively new source for the application of high-dose rate (HDR) brachytherapy. Radiation dose to the rectum is often a limiting factor in achieving the full prescribed dose to the target during brachytherapy of cervical cancer. The aim of this study was to measure radiation doses to the rectum in-vivo during HDR Co-60 brachytherapy. A total of eleven HDR brachytherapy treatments of cervical cancer were recruited in this study. A series of diodes incorporated in a rectal probe was inserted into the patient's rectum during each brachytherapy procedure. Real-time measured rectal doses were compared to calculated doses by the treatment planning system (TPS). The differences between calculated and measured dose ranged from 8.5% to 41.2%. This corresponds to absolute dose differences ranging from 0.3 Gy to 1.5 Gy. A linear relationship was observed between calculated and measured doses with linear regression R-2 value of 0.88, indicating close association between the measured and calculated doses. In general, absorbed doses for the rectum as calculated by TPS were observed to be higher than the doses measured using the diode probe. In-vivo dosimetry is an important quality assurance method for HDR brachytherapy of cervical cancer. It provides information that can contribute to the reduction of errors and discrepancies in dose delivery. Our study has shown that in-vivo dosimetry is feasible and can be performed to estimate the dose to the rectum during HDR brachytherapy using Co-60. (C) 2014 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved

Antifouling polysulfone membranes blended with green SiO2 from rice husk ash (RHA) for humic acid separation

This study investigated the effects of silica prepared from rice husk (RHA) as an antifouling additive in the polysulfone (PSf) membrane. The ultrafiltration mixed matrix PSf/rice husk silica (RHS) flat-sheet membrane was prepared via phase inversion technique at different percentages of silica concentration. The characterization and performance test were conducted on the prepared membrane. The thermal stability of the membrane was observed by using thermogravimetric analysis (TGA). The cross section area and particles distribution of additive were carried out by using the scanning electron microscope (SEM) while the surface morphology was investigated via field emission scanning electron microscope (FESEM). The surface roughness and hydrophilicity were also determined by using atomic force microscopy (AFM) and contact angle measurement respectively. The performance of the membrane was evaluated in terms of pure water flux (PWF), humic acid rejection and antifouling properties. The results of SEM, FESEM and AFM revealed that the incorporating of RHS improved the microstructure of the membrane especially at top layer and sub layer. The results also demonstrated that the mean pore size decreased and the hyrophilicity increased with an increase of RHS particles in PSf membrane. The performance result was found that the addition of RHS in the PSf membrane significantly improved the PWF, rejection and antifouling properties. The results indicated that the addition of 4 g RHS give the highest flux at 300.50 L/m2 h (LMH) and excellent mitigating fouling. The highest rejection was found at 3 g of RHS with a value of 98% for ultraviolet light (UV254) and 96% for Dissolved Organic Carbon (DOC)

Prevalence of sleep disordered breathing symptoms among Malay school children in a primary school in Malaysia

Sleep disordered breathing (SDB) is increasingly being diagnosed in children. However, there is no prevalence study done in Malaysia. The study objective was to evaluate the prevalence of SDB symptoms based on parental reports and associated risk factors among Malay school children aged 6 to 10 years old in a primary school using a translated University Michigan Paediatric Sleep Questionnaire (Malay UM-PSQ). The children whose parents responded to the questionnaire and consented were examined, documenting height, weight, skin fold thickness, neck and abdominal circumference, tonsillar size, nostril examination and presence of micrognathia or retrognathia. There were 550 respondents. The prevalence of parental report of SDB symptoms was 14.9 % (95 % CI 11.9, 17.9). Two hundred and eighty-five (51.8%) school children were males with mean age of 8.5 years (SD 1.1). The associated risk factors for SDB symptoms are male, obesity, large neck and waist circumference, positive history of asthma, history of recurrent tonsillitis, enlarged tonsil (> 4+) and enlarged nasal turbinate. Multivariate analysis showed that male gender is the only significant independent risk factor of SDB symptom

A study of risk factors in acute myocardial infarction of adults ages 18 to 45 in a tertiary referral centre for cardiology services in Malaysia's East Coast.

INTRODUCTION: Acute myocardial infarction (AMI) is the major cause of death worldwide. There is limited data on the characteristics of afflicted young adults. A recent increase in recreational drugs has been associated. No local studies have ever reliably attributed this to young adults. This study aims to study the characteristic of AMI cases among young adults and these associations. MATERIALS AND METHODS: This cross-sectional study was conducted at a tertiary referral centre for Cardiology services, Hospital Tengku Ampuan Afzan (HTAA), Kuantan, Pahang. It involved screening 818 patients presenting with AMI at the Emergency Department of HTAA over a one-year duration. Malaysian citizens aged 18 to 45 years newly diagnosed with AMI were included. Urinary samples were collected for recreational drug screening. RESULTS: The incidence of AMI cases among young adults in HTAA Kuantan, Pahang were 10.3 per 100 persons of total AMI cases in one year (95% Confidence Interval, 8.4%-12.6%). Fifty -eight patients who met the inclusion criteria were recruited, 1.7 % tested positive for amphetamines. Males made up 96.6% of the patients and the most common risk factor identified for young adults with AMI was smoking (N=45, 77.6%) followed by obesity (N=33, 56.9%). More than half (58.6%) of the patients had 3 cardiovascular disease risk factors or more. CONCLUSION: Recreational drug use at AMI presentation was negligible. Males made up the majority and smoking was the most prevalent risk factor. To date, this is the first study in Malaysia looking at the incidence of young adults with AMI and their preponderant characteristics