Assessment of airborne particulate matter (PM<inf>2.5</inf>) in university classrooms of varrying occupancy

Air pollution is a major concern in Pakistan. Levels of particulate matter (PM2.5) in educational built environments, have not yet been studied comprehensively in Pakistan. This study was conducted to assess relationships between indoor and outdoor particulate matter in classrooms of the University of the Punjab, Lahore, using a DUSTTRAK Aerosol Monitor (TSI Model 8520). Sampling for PM2.5 concentrations was carried out simultaneously outdoors and indoors in different classrooms on the campus. According to the level of occupancy three classrooms were selected i.e. Classroom I: low occupancy, Classroom II: medium occupancy and Classroom III: high occupancy. Simultaneous outdoor measurements were carried out at rooftop of each classroom. A tracer method was used to measure the air change per hour in each classroom. The 24 hour average concentrations of PM2.5 in Classrooms I, II and III were observed to be 282 μg/m3, 75 μg/m3 and 673 μg/m3 whereas 24 hour average outdoor levels were 324 μg/m3, 121 μg/m3 and 998μg/m3 respectively. Results showed a significant impact of ambient air and occupancy level on PM2.5 levels inside classrooms and all observed values exceeded the WHO limits

Comparative study of particulate matter in the transport microenvironment (buses) of Pakistan and UK

Transport microenvironments can contain higher levels of particulate matter due to infiltration from the roads, vehicular exhaust and commuter’s activities. The present study monitored PM, CO2, CO, temperature and relative humidity levels in diesel-powered buses in Pakistan and United Kingdom. Two routes of almost the same travelling distance were selected in Pakistan and the UK. Indoor air quality of the buses was monitored to determine the exposure faced by the commuters on inter-city journeys. While the observed levels in both countries were not in compliance with the WHO guidelines, levels of particulate matter were much higher in Pakistan than the concentrations in UK

Prevention of Radiocontrast-Induced Nephropathy after Coronary Angiography: N-Acetylcysteine plus Saline Hydration versus Saline Hydration

Purpose: To compare the incidence of radiocontrast-induced nephropathy (RCIN) in patients undergoing coronary angiography pretreated with N-acetylcysteine NAC plus saline hydration or saline hydration alone and to determine the association between various risk factors and RCIN.Methods: Patients were retrospectively evaluated over a one-year period. RCIN was defined as an acute rise in serum creatinine of at least 0.5 mg/dl or more than 25 % from baseline value. SPSS software, version 13 was used for data analysis.Results: Overall, 299 patients were studied. Thirteen patients (4.3%) developed RCIN. RCIN was 3.3 % in patients treated with hydration, and 8.3 % in patients treated with NAC plus hydration (p = 0.09). Inpatients with RCIN, the changes in creatinine and % change in creatinine after 24 h were significantly lower in the NAC plus hydration group (p = 0.039 and p = 0.042, respectively). RCIN was significantly associated with male gender (p = 0.017), history of renal failure (p = 0.006), ischemic heart disease (p =0.003), and diuretic treatment (p = 0.013).Conclusion: NAC plus saline hydration may not be more effective than saline hydration alone in decreasing RCIN after coronary angiography. Additional efforts to find an ideal preventive treatment are needed

Changes in particulate matter concentrations at different altitudinal levels with environmental dynamics

Ambient air quality is defined not only by the source strength but a variety of meteorological parameters as well. In the current study, ambient concentrations of PM along with temperature and relative humidity levels were monitored at seven different locations of Pakistan. A DustTrak DRX (Model 8533, TSI Inc.) was employed for twenty four hours real time monitoring of particulate matter at the selected sites. A considerable variation was observed in the 24 hour trend of particulate matter (PM) at different locations owing to variation in meteorological conditions due to different altitudes and seasons, and natural and anthropogenic sources in the vicinity. The highest average concentrations of PM2.5 (407μg/m3 were observed at highest elevation (Makra Peak, Shogran, 3089 m) while lowest averages (102 μg/m3) were obtained at the seaside (Hawks Bay, Karachi, 0 m).On the other hand PMTotal fraction exhibited highest levels at site B (506 μg/m3) and lowest at Site A (121 μg/m3).Correlation factors were determined for PM and meteorological parameters at each location. More research needs to be conducted to have a comprehensive knowledge about the physical parameters controlling particulate dispersal at different altitudes within the country

Seasonal variation of particulate matter in the ambient conditions of Khanspur, Pakistan

Concentrations of particulate matter tend to vary with shifting seasons. Levels of particulate matter were monitored during the summer and winter season in Khanspur, a high altitude tourist resort in Pakistan. A DustTrak DRX (Model 8533, TSI Inc.) and Kestrel 4500 Pocket Weather Tracker (Nielsen- Kellerman) were installed at selected site in Khanspur and run for 24 hours. During summer the 24- hour average concentrations of PM1, PM2.5, PM4, PM10 and PMTotal were 96 ± 26.42, 106± 29.02, 118± 33.3, 163± 52.5 and 209 ± 79.5 μg/m3 while these were considerably lower during the winter season for the same size fractions (62 ± 48.6, 63± 49.3, 63 ± 49.5, 65.33 ± 50.06 and 66.96 ± 50.78μg/m3). A one way ANOVA was applied on the obtained data and it was concluded that seasons have a substantial impact upon PM concentrations. Moreover, this study provides evidence that seasonal variation of particulate matter is influenced by meteorological parameters

Fe3+ @ ZnO/polyester based solar photocatalytic membrane reactor for abatement of RB5 dye

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordHeterogeneous photocatalysis, employing semiconductor metal oxides, especially at nano scale is a promising technique to mortify the dye residues from effluent. The photocatalysts on doping with a suitable dopant can be modified to enhance the photocatalytic activity. In this study, undoped and series of Fe3+ doped ZnO have been grown on polyester fabric through low temperature hydrothermal method to generate photocatalytic membrane reactors (PMRs). The material grown on the surface of fabric was characterized by XRD, EDX, SEM, TEM, STEM, AFM, XPS, ICP-MS, DRS and PL studies. For ZnO/PMR and Fe3+@ZnO/PMR photocatalytic activity was determined and examined to increase for Fe3+@ZnO/PMR in the solar region due to the reduction of band gap from 3.2 to 2.6 eV on Fe3+doping. The surface properties of PMRs were also determined by zeta potential and contact angle. The characterized ZnO and Fe3+@ZnO nano discs based PMRs have been used to degrade RB5 reactive dye on irradiating with artificial sunlight (D65, 72 W). The reaction parameters i.e. initial dye and oxidant concentration, pH and irradiation time have been optimized by Response Surface Methodology (RSM). The extent of dye degradation has been evaluated by UV/vis spectroscopy and FTIR. The maximum degradation achieved was 88.89% for ZnO/PMR and 98.34% for Fe3+@ZnO PMR in 180 min. The photocatalytic efficiency of Fe3+@ZnO PMR was investigated for 15 batches, with a slight gradual decrease in activity after eight batches.Endowment Fund Secretariat of University of Agriculture Faisalaba

Self‐perceived preparedness of undergraduate dental students in dental public universities in Malaysia: A national study

Aims: To evaluate the self-perceived preparedness of final-year dental undergraduate students in dental public universities in Malaysia. Methods: Final-year dental undergraduate students from six dental public universities in Malaysia were invited to participate in an online study using a validated Dental Undergraduates Preparedness Assessment Scale DU-PAS. Results: In total, about 245 students responded to the online questionnaire yielding a response rate of 83.05%. The age range of the respondents was 23-29 years with a mean age of 24.36 (SD 0.797). The total score obtained by the respondents was ranged from 48 to 100 with a mean score of 79.56 (SD 13.495). Weaknesses were reported in several clinical skills, cognitive and behavioural attributes. Conclusions: The preparedness of undergraduate students at six dental institutions in Malaysia was comparable to students from developed countries. The dental undergraduate preparedness assessment scale is a useful tool, and dental institutions may be used for self-assessment as well as to obtain feedback from the supervisors

Is there a uniform approach to the management of diffuse parenchymal lung disease (DPLD) in the UK? A national benchmarking exercise

BACKGROUND: Benchmarking is the comparison of a process to the work or results of others. We conducted a national benchmarking exercise to determine how UK pulmonologists manage common clinical scenarios in diffuse parenchymal lung disease (DPLD), and to determine current use and availability of investigative resources. We compared management decisions to existing international guidelines. METHODS: Consultant members of the British Thoracic Society were mailed a questionnaire seeking their views on the management of three common scenarios in DPLD. They were asked to choose from various management options for each case. Information was also obtained from the respondents on time served as a consultant, type of institution in which they worked and the availability of a local radiologist and histopathologist with an interest/expertise in thoracic medicine. RESULTS: 370 out of 689 consultants replied (54% response rate). There were many differences in the approach to the management of all three cases. Given a scenario of relapsing pulmonary sarcoidosis in a lady with multiple co-morbidities, half of respondents would institute treatment with a variety of immunosuppressants while a half would simply observe. 42% would refer a 57-year old lady with new onset DPLD for a surgical lung biopsy, while a similar number would not. 80% would have referred her for transplantation, but a fifth would not. 50% of consultants from district general hospitals would have opted for a surgical biopsy compared to 24% from cardiothoracic centres: this may reflect greater availability of a radiologist with special interest in thoracic imaging in cardiothoracic centres, obviating the need for tissue diagnosis. Faced with an elderly male with high resolution CT thorax (HRCT) evidence of usual interstitial pneumonia (UIP), three quarters would observe, while a quarter would start immunosuppressants. 11% would refer for a surgical biopsy. 14% of UK pulmonologists responding to the survey revealed they had no access to a radiologist with an interest in thoracic radiology. CONCLUSION: From our survey, it appears there is a lack of consensus in the management of DPLD. This may reflect lack of evidence, lack of resources or a failure to implement current guidelines

The state of ambient air quality in Pakistan—a review

Background and purpose: Pakistan, during the last decade, has seen an extensive escalation in population growth, urbanization, and industrialization, together with a great increase in motorization and energy use. As a result, a substantial rise has taken place in the types and number of emission sources of various air pollutants. However, due to the lack of air quality management capabilities, the country is suffering from deterioration of air quality. Evidence from various governmental organizations and international bodies has indicated that air pollution is a significant risk to the environment, quality of life, and health of the population. The Government has taken positive steps toward air quality management in the form of the Pakistan Clean Air Program and has recently established a small number of continuous monitoring stations. However, ambient air quality standards have not yet been established. This paper reviews the data being available on the criteria air pollutants: particulate matter (PM), sulfur dioxide, ozone, carbon monoxide, nitrogen dioxide, and lead. Methods: Air pollution studies in Pakistan published in both scientific journals and by the Government have been reviewed and the reported concentrations of PM, SO2, O3, CO, NO2, and Pb collated. A comparison of the levels of these air pollutants with the World Health Organization air quality guidelines was carried out. Results: Particulate matter was the most serious air pollutant in the country. NO2 has emerged as the second high-risk pollutant. The reported levels of PM, SO2, CO, NO2, and Pb were many times higher than the World Health Organization air quality guidelines. Only O3 concentrations were below the guidelines. Conclusions: The current state of air quality calls for immediate action to tackle the poor air quality. The establishment of ambient air quality standards, an extension of the continuous monitoring sites, and the development of emission control strategies are essential. © Springer-Verlag 2009