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In Korea, the issue of particulate matter pollution is growing, and many solutions are being developed to deal with it. Photocatalytic technology has been found to be helpful in removing precursors such as nitrogen oxides that cause particulate matter. In a microcosm setup, ISO 22197-1 has been successfully used to quantify the removal of nitrogen oxides from the specimen to which the photocatalyst is applied. However, owing to a lack of suitable tools, on-site measurement of real-scale efficacy is difficult. Depending on the substrate and surrounding circumstances at the application location, the photocatalyst may function at varying levels. Additionally, the expected photocatalytic effect may differ depending on the ambient air quality and sunlight irradiation intensity. This article describes two approaches for studying outdoor concrete photocatalysis. Standard gas measurement and dual-reactor measurement are the recommended evaluation approaches. The standard gas measurement method was found useful for assessing the applied photocatalyst itself as an outcome of field assessment. The performance of photocatalysts at different sites was found to be mutually exclusive and comparable. Over 180 min, on a building roof deck, the NO removal by the standard gas method was 0.68 ppm, whereas, at two shaded locations, the removal amount was 0.51 ppm (side wall) and 0.24 ppm (underpass) for 300 min. The dual reactor measurement approach, on the other hand, was discovered to be one of the most suitable methods for assessing how much of an improvement there has been in the air quality in areas where photocatalysts have been placed.

The feasibility of preparing TiO2/g-CN heterojunction from Ti-incorporated dried dye wastewater sludge is explored in this study. Two reaction routes of composite formation were evaluated. In the initial approach, one-step calcination of dried sludge and melamine mixture @600 °C was carried out. Detailed morphological and chemical characterizations showed that the one-step calcination route did not create TiO2/g-CN composites; instead, only N-doped anatase TiO2 composites were formed. Moreover, due to the non-uniform composition of organic content in the dried sludge, it was not easy to control the N doping level by varying melamine content (0-100%) in the precursor mix. However, successful formation of anatase TiO2 and g-CN was observed when a two-step calcination route was followed, i.e., via synthesis of anatase TiO2 from dried sludge, and later development of heterojunction by calcining (@550 °C) the TiO2 and melamine mixture. X-ray diffraction along with infrared and X-ray photoelectron spectroscopy verified the effective heterojunction. In addition, maximum atmospheric NO removal under UV and visible light were observed for the prepared composite when the melamine content in the precursor mixture was 70%. After 1 h of UV and visible light irradiation, the best TiO2/g-CN composite removed 25.71% and 13.50% of NO, respectively. Optical characterization suggested that the enhanced NO oxidation under UV/visible light was due to the bandgap narrowing and diminished photogenerated electron-hole recombination.

BackgroundPain is an inevitable part of the postoperative experience. Current study was designed to assess the pattern of analgesic use, the adequacy of post operative pain control by documenting pain scores, and patient satisfaction by documenting the pain perception score of the postoperative patients 48 hours after surgery.Materials and methodsThis was a formative research and includes a mix of descriptive cross-sectional study carried out in the department of Gynecology and Obstetrics, General surgery, and Orthopedics surgery of Chattagram Maa -O- Shishu Hospital Medical College (CMOSHMC) during the month of January, 2018 to July, 2019.ResultA total of 180 patients undergoing surgery were included in this study. Baseline data were collected both retrospectively and prospectively. Only analgesic used immediately after operation in three departments were Pethidine (100%). Diclofenac sodium suppository were used in appendectomy and cesarean section (50/60, 83%) and (26/60, 43%) respectively. Mostly, Diclofenac Sodium IV (55/60, 91%) was used in lower limb surgery. The maximum pain score were 5.3 (SD=2.3), 5.6 (SD =1.9), and 6.1 (SD =1.3) during coughing in the first 8 hour and minimum pain score 2.4 (SD =1.0), 2.2 (SD = 0.8) and 1.7 (SD=1.3) at rest 48 hours after cesarean section, appendectomy and lower limb surgery respectively. But pain score eventually increased during coughing 48 hours after surgery. After 48 hours of surgery maximum pain perception score 3.9 (SD = 0.9) in lower limb surgery and minimum perception score were 3.5 (SD =1.8) in cesarean section. Majority of the appendectomy patient (76%) satisfied with pain management where as only 43% satisfied in case of cesarean section.ConclusionThis study enabled the researchers to get a precise picture of the current state of POPM in different hospitals, as well as identify particular needs for improving such practices in health care facilities and implementing an educational intervention in order to improve the post operative pain management.

BackgroundPrioritizing problem-oriented undergraduate medical education is paramount to adequate management of pain in real life scenarios. The present research was conducted with an attempt to explore the important baseline information for pain medicine education and evaluation within undergraduate pharmacology curricula in Bangladesh.Materials and methodsThis descriptive cross-sectional study evaluates the curriculum (pharmacology portion of undergraduate medical curriculum), and written question (SAQ) of MBBS Examination of last ten years extending from January 2010 to November,2019 of all 7 universities offering MBBS degree. The evaluation was conducted through searching certain key phrases.ResultIn Pharmacology & Therapeutics portion of the curriculum, only 4 hours and 2 hours are allocated to discuss pain management in lecture and tutorial respectively. In the study period, average marks allocated in pharmacology written question papers was 4.4 (SD = 2.7) and the difference among studied universities was not significant (p value 0.7).ConclusionAllocated time in the curriculato teach pain management is very low and weightage received in assessment is also inadequate. Education on pain medication as well as management should receive more emphasis.

BackgroundUndergraduate research opportunities teach students not only how to conduct research, but they too learn problem-solving aptitudes. Participating in research also increases students’ interest is being involved and making special contributions to the academic field. Therefore, the aim of our study was intended to assess the attitude and perceived barriers toward research among the medical undergraduates of Bangladesh.MethodsA cross-sectional questionnaire survey was conducted among third, fourth, and fifth year students across medical colleges in Bangladesh, during the month of July, 2020 to December, 2020. A Google-linked questionnaire was disseminated to the students via different social platform and the responses were received through Google drive.ResultThe questionnaire survey received responses from 1279 students, with 94% claiming to be familiar with the scientific method. 82.7% of students mentioned they could design and execute a research project as well as can write scientific articles. More than half of the respondents (66.4%) expressed an interest in participating in research. Almost all respondents (96.7%) agreed that research is beneficial as it aid critical thinking and policy implementation. 79.8% of respondents opined that education on research methodology should be required in the medical curriculum. Majority of the respondents reported that lack of time and priorities to do research work because of compact academic tasks (89.1%), insufficient guidance (86.6%), lack of familiarities with research methodology (87.5%) and statistical analysis (85.2%) are the barriers of research.ConclusionOur findings indicated that Bangladeshi medical students have a positive attitude toward research and that research methodology should be taught in undergraduate medical education. In order to increase participation in research, the challenges identified by students should be addressed.

In this study, sludges generated from Ti-based flocculation of dye wastewater were used to retrieve photoactive titania (S-TiO2). It was heterojunctioned with graphitic carbon nitride (g-CN) to augment photoactivity under UV/visible light irradiance. Later the as-prepared samples were utilized to remove nitrogen oxides (NOx) in the atmospheric condition through photocatalysis. Heterojunction between S-TiO2 and g-CN was prepared through facile calcination (@550 °C) of S-TiO2 and melamine mix. Advanced sample characterization was carried out and documented extensively. Successful heterojunction was confirmed from the assessment of morphological and optical attributes of the samples. Finally, the prepared samples' level of photoactivity was assessed through photooxidation of NOx under both UV and visible light irradiance. Enhanced photoactivity was observed in the prepared samples irrespective of the light types. After 1 h of UV/visible light-based photooxidation, the best sample STC4 was found to remove 15.18% and 9.16% of atmospheric NO, respectively. In STC4, the mixing ratio of S-TiO2, to melamine was maintained as 1:3. Moreover, the optical bandgap of STC4 was found as 2.65 eV, where for S-TiO2, it was 2.83 eV. Hence, the restrained rate of photogenerated charge recombination and tailored energy bandgap of the as-prepared samples were the primary factors for enhancing photoactivity.

In this study, anatase titania was utilized to prepare a durable photocatalytic paint with substantially enhanced photoactivity towards NO oxidation. Consequently, to alleviate the choking effect of photocatalytic paint and incorporate self‐cleaning properties, the parent anatase titania was modified with Al(OH)3 and a number of organosilane (tetraethyl orthosilicate, propyltrimethoxysilane, triethoxy(octadecyl)silane, and trimethylchlorosilane) coatings. A facile hydrolysis approach in ethanol was employed to coat the parent titania. To facilitate uniform dispersion in photocatalytic paint and strong bonding with the prevailing organic matrix, it is necessary to avail both hydrophobic and hydrophilic regions on the titania surface. Therefore, during the preparation of modified titania, the weight proportion of the total weight of alkyl silane and trimethylchlorosilane was adjusted to a ratio of 1:1. As the parent titania has few hydrophilic portions on the surface, tetraethyl orthosilicate was coated with an organic silane having an extended alkyl group as a hydrophobic group and tetraethyl orthosilicate as a hydrophilic group. When these two silane mixtures are hydrolyzed simultaneously and coated on the surface of parent titania, a portion containing a large amount of tetraethyl orthosilicate becomes hydrophilic, and a part containing an alkyl silane becomes hydrophobic. The surface morphology and the modified titania’s optical attributes were assessed using X‐ray powder diffraction (XRD), scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDS), UV‐Vis diffuse reflectance spectroscopy (DRS), and electrochemical impedance spectroscopy (EIS) analysis. Based on the advanced characterizations, the NO removal mechanism of the modified titania is reported. The modified titania coated at 20 wt.% on the ceramic substrate was found to remove ~18% of NO under one h of UV irradiation. An extensive UV durability test was also carried out, whereby the coated surface with modified titania was exposed to 350 W/m2 of UV irradiance for 2 weeks. The results indicated that the coated surface appeared to preserve the self‐cleaning property even after oil spraying. Hence, facile hydrolysis of multiple organosilane in ethanol could be a viable approach to design the coating on anatase titania for the fabrication of durable photoactive paint.

Titanium oxide (TiO2) is a potential photocatalyst for removing toxic NOx from the atmosphere. Its practical application is, however, significantly limited by its low absorption into visible light and a high degree of charge recombination. The overall photocatalytic activity of TiO2 remains too low since it can utilize only about 4–5% of solar energy. Nitrogen doping into the TiO2 lattice takes advantage of utilizing a wide range of solar radiation by increasing the absorption capability towards the visible light region. In this work, N-doped TiO2, referred to as TC, was synthesized by a simple co-precipitation of tri-thiocyanuric acid (TCA) with P25 followed by heat treatment at 550 degrees C. The resulting nitrogen doping increased the visible-light absorption and enhanced the separation/transfer of photo-excited charge carriers by capturing holes by reduced titanium ions. As a result, TC samples exhibited excellent photocatalytic activities of 59% and 51% in NO oxidation under UV and visible light irradiation, in which the optimum mass ratio of TCA to P25 was found to be 10.

© 2020 Elsevier Ltd For the purpose of atmospheric NO removal, anatase TiO2/g-CN photocatalytic composites were prepared by using a facile template-free calcination route in atmospheric conditions. Considerably fiscal NP400 and laboratory-grade melamine were used as the precursor of the composites. Additionally, samples were prepared with different wt. ratios of TiO2 and melamine by using two distinct calcination temperatures (550 °C/600 °C). The morphological attributes of the composites were assessed with X-ray diffraction, scanning and transmission electron microscopy, infrared spectroscopy, and X-ray photoelectron spectroscopy. Additionally, the optical traits were evaluated and compared using UV–visible diffuse reflectance spectroscopy and photoluminescence analysis. Finally, the photodegradation potentials for atmospheric NO by using the as-prepared composites were assessed under both UV and visible light irradiation. All the composites showed superior NO oxidation compared to NP400 and bulk g-CN. For the composites prepared by using the calcination temperature of 550 °C, the maximum NO removal was observed when the NP400 to melamine ratio was 1:2, irrespective of the utilized light irradiation type. Whereas for increased calcination temperature (600 °C), the maximum NO removal was observed at the precursor mix ratio of 1:3 (NP400:melamine). Successfully narrowed energy bandgaps were perceived in the as-prepared composites. Moreover, a subsequent drop in NO2 generation during NO oxidation was observed under both UV and visible light irradiation. Interestingly, higher calcination temperature during the synthesis of the catalysts has shown a significant drop in NO2 generation during the photodegradation of NO.

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The purpose of the study was to effectively treat algae bloomed water while using a Ti-based coagulant (TiCl4) and recover photoactive novel anatase TiO2 from the flocculated sludge. Conventional jar tests were conducted in order to evaluate the coagulation efficiency, and TiCl4 was found superior compared to commercially available poly aluminum chloride (PAC). At a dose of 0.3 g Ti/L, the removal rate of turbidity, chemical oxygen demand (COD), and total phosphorus (TP) were measured as 99.8%, 66.7%, and 96.9%, respectively. Besides, TiO2 nanoparticles (NPs) were recovered from the flocculated sludge and scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX), and X-ray diffraction (XRD) analysis confirmed the presence of only anatase phase. The recovered TiO2 was found to be effective in removing gaseous CH3CHO and NOx under UV-A lamp at a light intensity of 10 W/m2. Additionally, the TiO2 mixed mortar blocks that were prepared in this study successfully removed atmospheric nitrogen oxide (NOx) under UV irradiance. This study is one of the first to prepare anatase TiO2 from flocculated algal sludge and it showed promising results. Further research on this novel TiO2 concerning internal chemical bonds and shift in the absorbance spectrum could explore several practical implications.

Background: The laparoscopic surgery technique has rapidly spread because of its several advantages over conventional open surgery.

© 2019 Elsevier Ltd This study focused on the preparation of undoped and Ca-doped titania from flocculation generated sludge. Initially, TiCl4 was utilised to perform coagulation and flocculation in synthetic wastewater and an optimised dose of coagulant was determined by evaluating the turbidity, dissolved organic carbon (DOC) and zeta potential of the treated water. Later, using Ca(OH)2 as a coagulant aid, the effects on effluent pH, turbidity and DOC removal were investigated. Both Ca-doped and undoped anatase TiO2 were prepared from the flocculated sludge for morphological and photocatalytic evaluation. During the standalone use of TiCl4, maximum turbidity and DOC removal were found at 11.63 and 14.54 mg Ti/L, respectively. At the corresponding coagulant dose, rapid deprotonation of water caused the pH of the effluent to reach below 3.77 mg Ti/L. Whereas, when using Ca(OH)2 as a coagulant aid, a neutral pH (7.26) was attained at a simultaneous dosing of 32.40 mg Ca/L and 14.54 mg Ti/L. When aided with Ca(OH)2, the turbidity removal was further increased by 54.28% and the DOC removal was somewhat similar to the standalone use of TiCl4. TiO2 was prepared by incinerating the collected sludge at 600 °C for 2 h. Both XRD and SEM analysis were conducted to observe the morphology of the prepared titania. The XRD pattern of the TiO2 showed only an anatase phase along with the presence of a high atomic proportion of Ca (4.14%). Consequently, a high amount of Ca atoms inhibited the level of TiO2 phase and no obvious presence of CaO was observed. The prepared Ca-doped TiO2 at the optimised dose of Ca(OH)2 was found to be inferior to the undoped TiO2 during the photodegradation of acetaldehyde. However, a reduced dose of Ca(OH)2 (

Primary biliary cirrhosis (PBC) is very closely associated with the presence of antimitochondrial antibodies (AMA). Nevertheless, 5 to 10% of patients with typical features of primary biliary cirrhosis do not have detectable AMA. They are referred to as AMA negative PBC. We report a case of PBC who was AMA-negative. The patient was a middle-aged woman seeking help of dermatologist for her complaint of itching. The diagnosis was confirmed by histopathology, whereas other possible causes of cirrhosis were excluded. How to cite this article Begum R, Mahtab MA, Mamun AA, Saha BK, Hossain SMS, Saha DC, Akbar SMF, Kamal M, Rahman S. A Case of Antimitochondrial Antibody Negative Primary Biliary Cirrhosis from Bangladesh and Review of Literature. Euroasian J Hepato-Gastroenterol 2015;5(2):122-126.

Traditionally, critical path method (CPM) is widely used with manual resource assignment for planning and scheduling of the construction projects. This is predominant in the construction industry of Bangladesh. Therefore, the industry often faces challenges to complete construction projects in minimum possible time with optimum use of resources. Although, concurrency-based scheduling is an efficient tool to reduce construction completion time, manual formulation of plans for construction operations using the technique is cumbersome (because of complex nature of real-life construction operations, for instance a real-life construction work involves complex interaction between activities, limited number of resources and resource-sharing among activities, etc.) With this viewpoint, the present study aims to introduce computer-aided simulation modelling-based approach to reduce the completion time of a resource-constrained construction operation utilizing the features of concurrency-based scheduling. The study also proposes a method to optimize the resource use of construction operation. A real-life construction work has been considered as the case construction operation for this study. Results indicate that the simulation model developed for the case project can efficiently generate work-flow plans with reduced construction durations compared to the work-flow plan of the actual schedule. The model can also help to optimize the use of resources. Furthermore, the model developed for the case project can easily be reshaped, expanded and applied to other construction operations.