80 research outputs found

    An approach to mathematical models as a tool for water and air quality management

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    Interactions between mathematical and biological sciences have been increasing rapidly in recent years. The use of system analysis and mathematical model for formulation and solving the environmental pollution is of relatively recent vintage and has been used widely since last three decades. These models can be used to conduct numerical experiments, test hypothesis and help to understand the response of environmental pollution. A mathematical model acts as a bridge between study of mathematics and application of mathematics in environmentand other fields. Modeling is an abstraction of reality and its ultimate objective is to explore the complexity of functions and structure of the system under study. Today, a wide variety of models belonging to different nature and category are available to understand the processes of the environment around us. Various models such as WASP, CE-QUAL-ICM, QUAL W2, AQUATOX, QUAL2K, IITAQ, PEARL, GRAM, UGEM, and IITLT etc. related to water and air quality are developed so far along with their principles, intended use and applications. These models generally simulate the basic physical, chemical and biological processes. In the present study, an attempt has been made to evaluate the concept and utilization of mathematical models in air and water quality management

    Monitoring of ambient air quality in relation to traffic density in Bareilly City (U.P.), India

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    An ambient air quality study was undertaken in Bareilly city, U.P., India during the year 2010 and 2011. The seasonal air quality data was obtained from ten monitoring sites across the city considering sampling site of Cantt as control site. The maximum (713.06±55.64 µg/m3) suspended particulate matter (SPM), sulphur dioxide (SO2) (80.08±4.77 µg/m3) and nitrogen oxides (NOx) (64.98±3.53 µg/m3) level was found at Choupla during the winter 2011. Among the annual mean values of air pollutants were analyzed, SPM level was found to be above the National Ambient Air Quality Standards (NAAQS) (200 µg/m3) at all the polluted sites. SO2 and NOx levels were below the threshold limits (80 µg/m3) as per NAAQS. The ambient air quality was correlated with the traffic density in the city. The pollution level was observed to be positively correlated with traffic density which is the major source of air pollution in the city. The ambient air quality at different monitoring sites was categorized into different pollution level on the basis of Oak ridge air quality index (ORAQI). Light to moderate air pollution conditions were present at different sites. Sampling site of Choupla (SVII) observe maximum ORAQI of 64.48 and 70.81 and falls under category of moderate pollution

    VCE early acoustic test results of General Electric's high-radius ratio coannular plug nozzle

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    Results of variable cycle engine (VCE) early acoustic engine and model scale tests are presented. A summary of an extensive series of far field acoustic, advanced acoustic, and exhaust plume velocity measurements with a laser velocimeter of inverted velocity and temperature profile, high radius ratio coannular plug nozzles on a YJ101 VCE static engine test vehicle are reviewed. Select model scale simulated flight acoustic measurements for an unsuppressed and a mechanical suppressed coannular plug nozzle are also discussed. The engine acoustic nozzle tests verify previous model scale noise reduction measurements. The engine measurements show 4 to 6 PNdB aft quadrant jet noise reduction and up to 7 PNdB forward quadrant shock noise reduction relative to a fully mixed conical nozzle at the same specific thrust and mixed pressure ratio. The influences of outer nozzle radius ratio, inner stream velocity ratio, and area ratio are discussed. Also, laser velocimeter measurements of mean velocity and turbulent velocity of the YJ101 engine are illustrated. Select model scale static and simulated flight acoustic measurements are shown which corroborate that coannular suppression is maintained in forward speed

    Free-jet acoustic investigation of high-radius-ratio coannular plug nozzles

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    The experimental and analytical results of a scale model simulated flight acoustic exploratory investigation of high radius ratio coannular plug nozzles with inverted velocity and temperature profiles are summarized. Six coannular plug nozzle configurations and a baseline convergent conical nozzle were tested for simulated flight acoustic evaluation. The nozzles were tested over a range of test conditions that are typical of a Variable Cycle Engine for application to advanced high speed aircraft. It was found that in simulate flight, the high radius ratio coannular plug nozzles maintain their jet noise and shock noise reduction features previously observed in static testing. The presence of nozzle bypass struts will not significantly affect the acousticn noise reduction features of a General Electric type nozzle design. A unique coannular plug nozzle flight acoustic spectral prediction method was identified and found to predict the measured results quite well. Special laser velocimeter and acoustic measurements were performed which have given new insights into the jet and shock noise reduction mechanisms of coannular plug nozzles with regard to identifying further benificial research efforts

    Free-jet acoustic investigation of high-radius-ratio coannular plug nozzles. Comprehensive data report, volume 2

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    Laser velocimeter data, collected as part of an acoustic investigation of coannular plug nozzles, is provided. The type of traverse, position, and histogram number is given along with the mean and turbulent velocity data. The velocites are normalized with respect to the outer flow velocity and the 'mixed' velocity

    Physico-chemical and microbiological characterization of the ground water across the city Bareilly (U.P.), India

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    The drinking water quality (underground water) of Bareilly city has been assessed by estimating physicochemical parameters and calculating Water Quality Index (WQI). Water Quality Index plays an important role in interpreting the information on water quality. The WQI of different sites shows that drinking water is of good quality. The correlation between different parameters was also estimated. During course of study the average value of physico-chemical parameters studied were observed as temperature 20.17 o C, turbidity 2.17 NTU, pH 8.13, electrical conductivity 1360 mmhos/cm, total dissolved solids 1218.9 mg/l, total hardness 515.0 mg/l chlorides 106.34 mg/l, alkalinity 342.15, fluorides 0.44 mg/l, sulphates 84.68 mg/l, nitrates 22.83 mg/l, DO 2.44 mg/l, BOD 1.26 mg/l. While average MPN were observed as 5.66 and average WQI as 21.48

    Study of planktonic diversity of river Ganga from Devprayag to Roorkee, Uttarakhand (India)

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    Analysis of water samples for planktonic diversity has been carried out for five sampling stations of river Ganga stretched over a distance of 125 kms from Devprayag to Roorkee. The investigation was carried out for a period of one year at five different sampling sites i.e. Sampling station A (Devprayag), Sampling station B (Rishikesh), Sampling station C (Haridwar) Sampling station D ( Pul Jatwara) and Sampling station E (Roorkee). In the present study of river Ganga, Among the zooplankton, Protozoa, Rotifera, Cladocera, Copepod, Ostracods constitute the main component and in phytoplankton Diatoms were dominated and class Blue green algae, green algae was found least during study period. Majority of zooplankton shows maximum occurrence and abundance during the high salinity period

    Assessment of water quality of River Ganges during Kumbh mela 2010

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    In the present study the water quality of Ganga River was assessed during Maha Kumbh-2010.  River water samples were collected from five sites.  Various Physico-Chemical and microbiological parameters were analysed. It was observed that all parameters were within the permissible limit according to WHO (2009) and BIS (2004) except most probable number that is the indication of low sanitary condition and it can further lead to the outbreak of diseases. During this mass bathing two sites were found to be more affected than the other three sites. These were noted to Har-ki-pauri and Mayapur ghat at Haridwar, at these sites parameters are observed to be slightly raised in comparison to other three sites

    Temporospatial shifts within commercial laboratory mouse gut microbiota impact experimental reproducibility

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    Experimental reproducibility in mouse models is impacted by both genetics and environment. The generation of reproducible data is critical for the biomedical enterprise and has become a major concern for the scientific community and funding agencies alike. Among the factors that impact reproducibility in experimental mouse models is the variable composition of the microbiota in mice supplied by different commercial vendors. Less attention has been paid to how the microbiota of mice supplied by a particular vendor might change over time. Results In the course of conducting a series of experiments in a mouse model of malaria, we observed a profound and lasting change in the severity of malaria in mice infected with Plasmodium yoelii; while for several years mice obtained from a specific production suite of a specific commercial vendor were able to clear the parasites effectively in a relatively short time, mice subsequently shipped from the same unit suffered much more severe disease. Gut microbiota analysis of frozen cecal samples identified a distinct and lasting shift in bacteria populations that coincided with the altered response of the later shipments of mice to infection with malaria parasites. Germ-free mice colonized with cecal microbiota from mice within the same production suite before and after this change followed by Plasmodium infection provided a direct demonstration that the change in gut microbiota profoundly impacted the severity of malaria. Moreover, spatial changes in gut microbiota composition were also shown to alter the acute bacterial burden following Salmonella infection, and tumor burden in a lung tumorigenesis model. Conclusion These changes in gut bacteria may have impacted the experimental reproducibility of diverse research groups and highlight the need for both laboratory animal providers and researchers to collaborate in determining the methods and criteria needed to stabilize the gut microbiota of animal breeding colonies and research cohorts, and to develop a microbiota solution to increase experimental rigor and reproducibility

    Mortality and pulmonary complications in patients undergoing surgery with perioperative sars-cov-2 infection: An international cohort study

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    Background The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (740%) had emergency surgery and 280 (248%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (261%) patients. 30-day mortality was 238% (268 of 1128). Pulmonary complications occurred in 577 (512%) of 1128 patients; 30-day mortality in these patients was 380% (219 of 577), accounting for 817% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 175 [95% CI 128-240], p<00001), age 70 years or older versus younger than 70 years (230 [165-322], p<00001), American Society of Anesthesiologists grades 3-5 versus grades 1-2 (235 [157-353], p<00001), malignant versus benign or obstetric diagnosis (155 [101-239], p=0046), emergency versus elective surgery (167 [106-263], p=0026), and major versus minor surgery (152 [101-231], p=0047). Interpretation Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research
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