Annual Average Basis Research Articles

Modeling methane oxidation in landfill cover soils as indicator of functional stability with respect to gas management

ABSTRACTA performance-based method for evaluating methane (CH4) oxidation as the best available control technology (BACT) for passive management of landfill gas (LFG) was applied at a municipal solid waste (MSW) landfill in central Washington, USA, to predict when conditions for functional stability with respect to LFG management would be expected. The permitted final cover design at the subject landfill is an all-soil evapotranspirative (ET) cover system. Using a model, a correlation between CH4 loading flux and oxidation was developed for the specific ET cover design. Under Washington’s regulations, a MSW landfill is functionally stable when it does not present a threat to human health or the environment (HHE) at the relevant point of exposure (POE), which was conservatively established as the cover surface. Approaches for modeling LFG migration and CH4 oxidation are discussed, along with comparisons between CH4 oxidation and biodegradation of non-CH4 organic compounds (NMOCs). The modeled oxidation capacity of the ET cover design is 15 g/m2/day under average climatic conditions at the site, with 100% oxidation expected on an annual average basis for fluxes up to 8 g/m2/day. This translates to a sitewide CH4 generation rate of about 260 m3/hr, which represents the functional stability target for allowing transition to cover oxidation as the BACT (subject to completion of a confirmation monitoring program). It is recognized that less than 100% oxidation might occur periodically if climate and/or cover conditions do not precisely match the model, but that residual emissions during such events would be de minimis in comparison with published limit values. Accordingly, it is also noted that nonzero net emissions may not represent a threat to HHE at a POE (i.e., a target flux between 8 and 15 g/m2/day might be appropriate for functional stability) depending on the site reuse plan and distance to potential receptors.Implications: This study provides a scientifically defensible method for estimating when methane oxidation in landfill cover soils may represent the best available control technology for residual landfill gas (LFG) emissions. This should help operators and regulators agree on the process of safely eliminating active LFG controls in favor of passive control measures once LFG generation exhibits asymptotic trend behavior below the oxidation capacity of the soil. It also helps illustrate the potential benefits of evolving landfill designs to include all-soil vegetated evapotranspirative (ET) covers that meet sustainability objectives as well as regulatory performance objectives for infiltration control.

Characteristics and Source Analysis of Atmospheric Carbonaceous Aerosols in the Cities of Hangzhou and Ningbo

To investigate the seasonal variations and sources of carbonaceous aerosols in the cities of Hangzhou and Ningbo, field PM2.5 sampling was conducted at four representative sites (two urban, one suburban, and one rural) in this region from December 2014 to November 2015. A thermal/optical carbon analyzer was employed to analyze both organic carbon (OC) and elemental carbon (EC) contents in PM2.5 by identifying eight different carbon fractions, including OC1, OC2, OC3, OC4+OPC, EC1-OPC, EC2, and EC3. Based on these fractions, OC and EC were defined as OC1+OC2+OC3+OC4+OPC and EC1+EC2+EC3-OPC, respectively; total carbon (TC) was calculated as the sum of OC and EC; and total carbonaceous aerosols (TCAs) were quantified via the sum of organic aerosols (OAs; converted from OC) and EC. The results showed the following. ①The annual average level of TC in this region was (14.3±4.1) μg·m-3, accounting for (26.2±6.5)% of the annual average PM2.5 concentration. The annual average OC and EC concentrations were (11.3±3.4) μg·m-3 and (3.0±0.9) μg·m-3, respectively. The highest TC level was observed in winter among the four seasons. ②The annual average TCA concentration in this region was (25.6±7.5) μg·m-3, contributing (42.2±10.0)% of PM2.5. In addition, secondary organic carbon (SOC) was also estimated by the commonly applied EC method. It was found that SOC contributed (41.1±5.5)% to OC on an annual average basis. ③The sources of carbonaceous aerosols were determined using the correlation between OC and EC, OC/EC mass ratio, and different carbon fraction characteristics. The annual average OC/EC ratio in this region was 4.7±1.7, which falls in the diagnostic ratio range for vehicular emissions, coal combustion, and biomass burning, indicating these sources are probably the major contributors of the regional carbonaceous aerosols. Moreover, a higher char-EC/soot-EC ratio was observed during winter and autumn at all sites, possibly implying the enhanced biomass burning activities during these two seasons.

Speciation of organic fraction does matter for source apportionment. Part 1: A one-year campaign in Grenoble (France)

PM10 source apportionment was performed by positive matrix factorization (PMF) using specific primary and secondary organic molecular markers on samples collected over a one year period (2013) at an urban station in Grenoble (France). The results provided a 9-factor optimum solution, including sources rarely apportioned in the literature, such as two types of primary biogenic organic aerosols (fungal spores and plant debris), as well as specific biogenic and anthropogenic secondary organic aerosols (SOA). These sources were identified thanks to the use of key organic markers, namely, polyols, odd number higher alkanes, and several SOA markers related to the oxidation of isoprene, α-pinene, toluene and polycyclic aromatic hydrocarbons (PAHs). Primary and secondary biogenic contributions together accounted for at least 68% of the total organic carbon (OC) in the summer, while anthropogenic primary and secondary sources represented at least 71% of OC during wintertime. A very significant contribution of anthropogenic SOA was estimated in the winter during an intense PM pollution event (PM10>50μgm−3 for several days; 18% of PM10 and 42% of OC). Specific meteorological conditions with a stagnation of pollutants over 10days and possibly Fenton-like chemistry and self-amplification cycle of SOA formation could explain such high anthropogenic SOA concentrations during this period. Finally, PMF outputs were also used to investigate the origins of humic-like substances (HuLiS), which represented 16% of OC on an annual average basis. The results indicated that HuLiS were mainly associated with biomass burning (22%), secondary inorganic (22%), mineral dust (15%) and biogenic SOA (14%) factors. This study is probably the first to state that HuLiS are significantly associated with mineral dust.

A method for estimating direct normal irradiation from GOES geostationary satellite imagery: Validation and application over Northeast Brazil

Abstract The mapping and monitoring of Direct Normal Irradiance (DNI) is most relevant for the proper installation of solar power plants that use concentrating solar systems. This paper presents a satellite-based method for estimating DNI and daily direct normal irradiation (Qn) that uses a minimal set of regional meteorological information and avoids empirical adjustment with ground-based radiometric data. The focus of the validation and application were on the Northeast Brazil region (NEB), which exhibits high solar radiation levels throughout the year. Two basic parameters for satellite-derived DNI estimates are: (i) DNI under clear-sky conditions DNIclear (computed from the REST model) and (ii) cloud cover C (estimated from GOES visible imagery). The first validations were performed by comparison with measurements from three radiometric stations of the SONDA network in the NEB (Petrolina, Natal and Sao Luis) during 2007–2008. Overall, the results confirmed the good performance of the proposed model. DNI daily cycles in conditions of clear and partially cloudy skies were represented satisfactorily, with daily average errors within ±25 W m−2. Good linearity was found between the measured and satellite-estimated Qn, with coefficients of determination (R2) ranging from 0.84 to 0.89. The average values of MBE (Mean Bias Error) and RMSE (Root Mean Square Error) over all sites were −1.7% and 18.7%, respectively. In addition, seasonal and annual average maps of direct normal irradiation were generated over NEB for 2008. It was found that the spatial–temporal variability of Qn is strongly modulated by meteorological systems acting in the region, such as the ITCZ (Intertropical Convergence Zone). The mapped results reveal that the highest value was approximately 22 MJ m−2 on an annual average basis, and higher values occurred in areas of semi-arid climate. The proposed satellite-based model may be applied for providing information of DNI (with a spatial resolution of 4 km), particularly over regions without in situ measurements, and suggests good accuracy for climatic and solar resource studies.

Modeling humid air condensation in waste natural gas-powered atmospheric water harvesting systems

4% of the natural gas produced globally is flared at oilfields due to the absence of gas handling infrastructure and unfavorable economics. Recent work has proposed the utilization of this excess gas for atmospheric water harvesting (AWH) for oilfield operations, wherein gas-powered refrigeration cycles generate the cooling capacity for large scale dehumidification, via condensation. This work develops an indepth, comprehensive, analytical modeling framework to predict the water condensation in waste gas-powered AWH systems. Firstly, gas powered refrigeration systems are analyzed to identify key system parameters and considerations. Secondly, an analytical model is developed to capture the complex heat and mass transfer phenomena associated with condensation of humid air in a fin and tube heat exchanger. This involves using heat and mass transfer relations to estimate the dehumidification process line. The model can predict the water condensation rate as a function of the gas flow rate, ambient weather and the refrigeration system utilized. The model is used to predict flared gas-based water harvests in the Eagle Ford (Texas) and Bakken (North Dakota) Shale oilfields, which account for the majority of US flaring. Results indicate that 1 cubic meter of natural gas can condense 2.3 and 0.65gallons water (on an annual average basis) in Texas and North Dakota, respectively. The weather-dependent condensation rates range from 3 to 10 (Texas) and 0 to 0.8 (North Dakota) gallons/day/square meter of condenser area. Overall, flared gas-based AWH can utilize 77% and 40% of the excess gas in Texas and North Dakota, respectively. This work analyzes various aspects of humid air condensation and evaluates the sensitivity of the condensation rate to key engineering parameters. Overall, this work develops the foundational modeling tool to predict the performance of all types of humid air condensation systems.

Statistical analysis for the characterization of solar energy utilization and inter-comparison of solar radiation at two sites in Cyprus

A statistical analysis and inter-comparison of the solar radiation at two sites in Cyprus representing two different climate regimes of the island (Athalassa-inland plain vs Larnaca-coastal location) covering the period January 2013–December 2015 is presented. Mean annual and mean monthly daily totals of the global, horizontal beam and diffuse radiation and their frequency distribution at both sites are computed and discussed. The values of skewness and kurtosis coefficients are used to define the frequency distribution type of the above radiation parameters on a monthly basis. The statistical analysis is extended to the daily clearness index (KT), diffuse ratio (KD), and the ratio of horizontal beam to global radiation (KB,G). Furthermore, the influencing factors on the magnitude of the radiation components were examined. The value of KT was used to classify three different types of days such as clear, partially cloudy and cloudy days. Then, a statistical analysis of the solar radiation components was performed. On an average annual basis, more than 80% of the days are classified as either clear or partially cloudy at both stations. Additionally, the influence of the atmospheric absorption and scattering of the solar radiation under clear skies was examined on the basis of the Linke turbidity factor (TL). The results of this analysis are used to characterize and compare the radiation regimes of the two sites. Both sites have relatively high intensity of global and direct horizontal radiation. The annual average daily global radiation intensity is 18.5MJm−2 at Athalassa and 19.9MJm−2 at Larnaca. The horizontal beam radiation is 13.1MJm−2 for Athalassa and 14.2MJm−2 for Larnaca. Therefore, the fraction of the beam component of the global radiation is comparatively high at both sites, as indicated by the annual average daily fraction which is greater than 0.600. Generally, Larnaca has slightly higher rates of global radiation than Athalassa, as indicated by the average yearly cumulative global irradiation which is 6763MJm−2 for Athalassa and 7274MJm−2 for Larnaca.

Diurnal Variation of Cosmic Ray Intensity at Different Group of Geomagnetic Index (Ap)

The solar modulation of Galactic Cosmic Rays (GCR) is revealed in the record of neutron monitors in terms of daily variation. Day-to-day and long term basis daily variations have been investigated for the recent period from 1965 to 2015 along with geomagnetic disruption index Ap on twelve-monthly average basis. Here Ap index has been used as a placeholder for the solar bring on interplanetary disturbances. It is create that, in general on an annual average basis, both the diurnal amplitude as well as the diurnal phase is considerably lower in the years of low Ap values, through the period 1965 to 2015. Such as a result was also informed for the earlier periods. However, anomalous and determined results for the diurnal variations have been received when the daily values of Ap are diffused in five groups with the first group demonstrating low Ap condition (i.e. quite periods) and the last group naturally representing the disturbed conditions.

Understanding the past to interpret the future: comparison of simulated groundwater recharge in the upper Colorado River basin (USA) using observed and general-circulation-model historical climate data

In evaluating potential impacts of climate change on water resources, water managers seek to understand how future conditions may differ from the recent past. Studies of climate impacts on groundwater recharge often compare simulated recharge from future and historical time periods on an average monthly or overall average annual basis, or compare average recharge from future decades to that from a single recent decade. Baseline historical recharge estimates, which are compared with future conditions, are often from simulations using observed historical climate data. Comparison of average monthly results, average annual results, or even averaging over selected historical decades, may mask the true variability in historical results and lead to misinterpretation of future conditions. Comparison of future recharge results simulated using general circulation model (GCM) climate data to recharge results simulated using actual historical climate data may also result in an incomplete understanding of the likelihood of future changes. In this study, groundwater recharge is estimated in the upper Colorado River basin, USA, using a distributed-parameter soil-water balance groundwater recharge model for the period 1951–2010. Recharge simulations are performed using precipitation, maximum temperature, and minimum temperature data from observed climate data and from 97 CMIP5 (Coupled Model Intercomparison Project, phase 5) projections. Results indicate that average monthly and average annual simulated recharge are similar using observed and GCM climate data. However, 10-year moving-average recharge results show substantial differences between observed and simulated climate data, particularly during period 1970–2000, with much greater variability seen for results using observed climate data.

Feeding management, production and performance of 13 pasture-based dairy farms in a Mediterranean environment

Physical performance data from 13 dairy farms in Western Australia, six feeding all concentrate in the milking parlour and seven feeding a portion of concentrate in a partial mixed ration (PMR) with forage, were collected between March 2012 and June 2013. Each farm was visited 13 times at intervals of 4–6 weeks, and feed intake and milk production was recorded on each visit. Four farms had access to fresh pasture all year round via irrigation. Milk yield (MY) and composition data was calculated daily from milk processor records. Pasture dry matter intake (DMI) was estimated based on metabolisable energy supply and requirements according to published feeding standards. All milk and feed-related measures were significantly affected by visit date (P < 0.01). Mean annual concentrate intake and MY was 2082 ± 344 kg/cow and 7679 ± 684 kg/cow, respectively. Daily concentrate DMI was greatest in May 2012 (8.9 ± 2.2 kg/cow), near the end of the non-grazing season, and lowest in August 2012 (5.1 ± 1.5 kg/cow). On an average annual basis, PMR farms provided 22 ± 15% of total concentrate fed as part of a PMR, and 28 ± 11% of total concentrates and by-products fed as part of a PMR. Daily grazed pasture DMI was highest on all farms in September 2012 (12.9 ± 2.4 kg/cow), and averaged 6.6 kg/cow on the four irrigated farms between January and May. Daily yield of energy-corrected milk was highest in September 2012 (26.9 kg/cow) and lowest in January 2013 (21.9 kg/cow). Milk fat content was highest in summer and lowest in winter; the reverse was true of milk protein. Feed conversion efficiency was significantly affected by visit date, but mean feed conversion efficiency was the same (1.37) for in-parlour and PMR farms. Overall there was some evidence that PMR feeding systems on Western Australian dairy farms are not optimised to their full potential, but a high degree of variability in performance between all farms was also apparent.

Capital Flight from a Small Developing Asia Pacific Economy

Capital flight from a small developing country in the Asia Pacific region, Fiji, is estimated using a variant of the residual approach. The findings show that between 1991 and 2009, approximately US$5 billion, averaging some US$265 million per annum has leaked out of Fiji in the form of capital flight. On an annual average basis, this has translated into 12 percent of Fiji’s gross domestic product; 19 percent of imports bills and 17 percent of lost tax revenues. The implications of this finding is that Fiji’s policymakers need to institute policies that focus on long-term secure and stable business and political environment. Some of these may include making the domestic business and investment environment more attractive, reforming the foreign investment tax incentives, retaining qualified and skilled people, eliminating institutional weaknesses in banking systems, and effective enforcement of banking and customs regulations relating to transfers of financial capital.

A case study of potential human health impacts from petroleum coke transfer facilities

ABSTRACTPetroleum coke or “petcoke” is a solid material created during petroleum refinement and is distributed via transfer facilities that may be located in densely populated areas. The health impacts from petcoke exposure to residents living in proximity to such facilities were evaluated for a petcoke transfer facilities located in Chicago, Illinois. Site-specific, margin of safety (MOS) and margin of exposure (MOE) analyses were conducted using estimated airborne and dermal exposures. The exposure assessment was based on a combined measurement and modeling program that included multiyear on-site air monitoring, air dispersion modeling, and analyses of soil and surfaces in residential areas adjacent to two petcoke transfer facilities located in industrial areas. Airborne particulate matter less than 10 microns (PM10) were used as a marker for petcoke. Based on daily fence line monitoring, the average daily PM10 concentration at the KCBX Terminals measured on-site was 32 μg/m3, with 89% of 24-hr average PM10 concentrations below 50 μg/m3 and 99% below 100 μg/m3. A dispersion model estimated that the emission sources at the KCBX Terminals produced peak PM10 levels attributed to the petcoke facility at the most highly impacted residence of 11 μg/m3 on an annual average basis and 54 μg/m3 on 24-hr average basis. Chemical indicators of petcoke in soil and surface samples collected from residential neighborhoods adjacent to the facilities were equivalent to levels in corresponding samples collected at reference locations elsewhere in Chicago, a finding that is consistent with limited potential for off-site exposure indicated by the fence line monitoring and air dispersion modeling. The MOE based upon dispersion model estimates ranged from 800 to 900 for potential inhalation, the primary route of concern for particulate matter. This indicates a low likelihood of adverse health effects in the surrounding community. Implications: Handling of petroleum coke at bulk material transfer facilities has been identified as a concern for the public health of surrounding populations. The current assessment, based on measurements and modeling of two facilities located in a densely populated urban area, indicates that petcoke transport and accumulation in off-site locations is minimal. In addition, estimated human exposures, if any, are well below levels that could be anticipated to produce adverse health effects in the general population.

Water depletion: An improved metric for incorporating seasonal and dry-year water scarcity into water risk assessments

We present an improved water-scarcity metric we call water depletion, calculated as the fraction of renewable water consumptively used for human activities. We employ new data from the WaterGAP3 integrated global water resources model to illustrate water depletion for 15,091 watersheds worldwide, constituting 90% of total land area. Our analysis illustrates that moderate water depletion at an annual time scale is better characterized as high depletion at a monthly time scale and we are thus able to integrate seasonal and dry-year depletion into the water depletion metric, providing a more accurate depiction of water shortage that could affect irrigated agriculture, urban water supply, and freshwater ecosystems. Applying the metric, we find that the 2% of watersheds that are more than 75% depleted on an average annual basis are home to 15% of global irrigated area and 4% of large cities. An additional 30% of watersheds are depleted by more than 75% seasonally or in dry years. In total, 71% of world irrigated area and 47% of large cities are characterized as experiencing at least periodic water shortage.

Sea Surface Temperature Warming Patterns and Future Vegetation Change

Abstract Recent modeling studies of future vegetation change suggest the potential for large-scale forest die-off in the tropics. Taken together with observational evidence of increasing tree mortality in numerous ecosystem types, there is clearly a need for projections of vegetation change. To that end, the authors have performed an ensemble of climate–vegetation experiments with the National Science Foundation–DOE Community Atmosphere Model (CAM) coupled to the Community Land Model (CAM–CLM-CN) with its dynamic vegetation model enabled (CAM–CLM-CNDV). To overcome the limitations of using a single model, the authors employ the sea surface temperature (SST) warming patterns simulated by eight different models from the Coupled Model Intercomparison Program phase 3 (CMIP3) as boundary conditions. Since the SST warming pattern in part dictates how precipitation may change in the future, in this way a range of future vegetation–climate trajectories can be produced. On an annual average basis, this study’s CAM–CLM-CN simulations do not produce as large a spread in projected precipitation as the original CMIP3 archive. These differences are due to the tendency of CAM–CLM-CN to increase tropical precipitation under a global warming scenario, although this response is modulated by the SST warming patterns imposed. However, the CAM–CLM-CN simulations reproduce the enhanced dry season in the tropics simulated by CMIP3. These simulations show longer fire seasons and increases in fractional area burned. In one ensemble member, extreme droughts over tropical South America lead to fires that remove vegetation cover in the eastern Amazon, suggesting that large-scale die-offs are an unlikely but still possible event.

Spatial and temporal variability of sources of ambient fine particulate matter (PM<sub>2.5</sub>) in California

Abstract. To identify major sources of ambient fine particulate matter (PM2.5, dp < 2.5 μm) and quantify their contributions in the state of California, a positive matrix factorization (PMF) receptor model was applied on Speciation Trends Network (STN) data, collected between 2002 and 2007 at eight distinct sampling locations, including El Cajon, Rubidoux, Los Angeles, Simi Valley, Bakersfield, Fresno, San Jose, and Sacramento. Between five to nine sources of fine PM were identified at each sampling site, several of which were common among multiple locations. Secondary aerosols, including secondary ammonium nitrate and ammonium sulfate, were the most abundant contributor to ambient PM2.5 mass at all sampling sites, except for San Jose, with an annual average cumulative contribution of 26 to 63%, across the state. On an annual average basis, vehicular emissions (including both diesel and gasoline vehicles) were the largest primary source of fine PM at all sampling sites in southern California (17–18% of total mass), whereas in Fresno and San Jose, biomass burning was the most dominant primary contributor to ambient PM2.5 (27 and 35% of total mass, respectively), in general agreement with the results of previous source apportionment studies in California. In Bakersfield and Sacramento, vehicular emissions and biomass burning displayed relatively equal annual contributions to ambient PM2.5 mass (12 and 25%, respectively). Other commonly identified sources at all sites included aged and fresh sea salt and soil, which contributed to 0.5–13%, 2–27%, and 1–19% of the total mass, respectively, across all sites and seasons. In addition, a few minor sources were identified exclusively at some of the sites (e.g., chlorine sources, sulfate-bearing road dust, and different types of industrial emissions). These sources overall accounted for a small fraction of the total PM mass across the sampling locations (1 to 15%, on an annual average basis).

Field Hydrology of Water Balance Covers for Waste Containment

Abstract A study was conducted at 12 sites across the United States to evaluate field-scale hydrology of landfill final covers using water balance methods to control percolation. The sites were located in climates ranging from arid to humid, with annual precipitation varying from 119 to 1,263 mm. Fifteen test sections were constructed with large ( 10 × 20 m ) drainage lysimeters for continuous and direct monitoring of the water balance over a period of 3–6 years. Monolithic and capillary barrier designs were used for water storage, and plant communities consisting of grasses, grasses and shrubs, or grasses and trees were used to promote evapotranspiration. Data from these test sections are analyzed along with data from 10 other sites in the literature to draw general inferences regarding the hydrology of water balance covers. Percolation ranges from 0 to 225 mm / year (0–34% of precipitation) on an average annual basis and is shown to be affected by annual precipitation, preferential flow, and sto...

Wind speed reductions as influenced by woody hedgerows grown for biomass in short rotation alley cropping systems in Germany

The cultivation of fast growing trees on agricultural sites is an area undergoing a growth in interest due to the rising demand for woody biomass as a source of bioenergy. Short rotation alley cropping systems (SRACS) represent a promising possibility to combine annual crops for food, fodder or bioenergy with woody plants for biomass production, doing so through an integration of hedgerows of fast growing trees into conventional agricultural sites. Against such developments, the question has arisen as to what extent hedgerows in SRACS can act as an effective windbreak despite their management-related low height of only a few meters. On the basis of multiannual recorded wind velocity data in high resolution at two sites in Germany, it could be shown that the wind speed on crop alleys was reduced significantly by such hedgerows. At the central point of 24 m wide crop alleys, the wind speed decreased on an annual average basis by more than 50 % when compared to the wind speeds of open field. The overall amount of reduction was strongly dependent on the location within the crop alleys, the height of trees, the distance between two hedgerows, and their orientation. In reflection upon these results, it was concluded that the establishment of SRACS could lead to enhanced soil protection against wind erosion and thus to ecological and economic benefits for agricultural sites.

Design and operating experiences of full-scale municipal membrane bioreactors in Japan

In Japan, membrane bioreactor (MBRs) have been installed in 17 small-scale municipal wastewater treatment plants (WWTPs) in the past 8 years, together with two recently installed MBRs for larger-scale WWTPs. In this study, design and operating data were collected from 17 of them as part of a follow-up survey, and aspects including system design, biological treatment, membrane operation, problems and costs were overviewed. Because most of the MBRs were designed according to standardized guidance, system configuration of the plants was similar; pre-denitrification using the Modified Ludzack-Ettinger (MLE) process with membrane units submerged in aerobic tanks, following a fine screen and flow equalization tank. This led to effluent quality with biochemical oxygen demand and T-N of less than 3.5 and 7.4 mg/L, respectively, for nine plants on an annual average basis. It was a common practice in extremely under-loaded plants to operate the membrane systems intermittently. Frequency of recovery cleaning events was plant-specific, mostly ranging from 1 to 5 times/year. Cost evaluation revealed that specific construction costs for the small-scale MBRs were no more than for oxidation ditch plants. Although specific energy consumption values tended to be high in the under-loaded plants, the demonstration MBR, where several energy reducing measures had been incorporated, attained specific energy consumption of 0.39 kWh/m(3) under full-capacity operation.

CLIMATE CHANGE IMPACT ASSESSMENT ON WATERSHED HYDROLOGY: A COMPARISON OF THREE APPROACHES

Several methods of impact assessment have been developed over the years which basically incorporate future climate projections of atmospheric-ocean cir culation based climate models into the simulation o f land surface hydrological processes. This study attempte d to evaluate three methods of climate change impac t assessment: (a) Frequency perturbation method, (b) direct method and (c) delta change method. A wellcalibrated hydrologic model, Soil and Water Assessment Tool (SWAT), was used in watershed simulation for climate projections of mid-century by ten Globa l Climate Models (GCMs). The frequency perturbation method found precipitation decrease by 17% and reduction in temperature by 0.43°C on an average annual basis. The changes when applied through the simulat ion model resulted in 13% reduction in Evapotranspiration (ET) and 25% reduction in water yield. Other two methods produced different set of results. It’s not conclusive to say which method pe rformed better. The frequency perturbation method produced most extreme changes while direct method had the least magnitude of changes projected for the mid-century. Changes in ET and water yield due to c hanges in future climate are likely to have severe implications for the water availability. However, m ore research is needed to evaluate several other im pact assessment methods for more reliable analysis.

A Modified Approach to Analyze Thermal Comfort Classification

A thermal stress index of a geographic location over a period of time can provide knowledge of overall climate perceptible to the general public. Out of the three approaches to assessing thermal comfort namely, rational, empirical and direct, the direct approach is being used in the present study because of easy availability of all inputs and reasonable comprehension of the assessments. Assessment and ranking of cities using this approach based on the percentage of comfortable hours alone may however be erroneous and misleading as this approach does not consider the percentages of uncomfortable classes which could often be substantially high. The modified approach for thermal comfort classification demonstrates cumulative representation of all classes of thermal comfort including uncomfortablity and provides relative ranking of cities. Analysis of the results is presented here for five megacities (Delhi, Mumbai, Chennai, Kolkata and Hyderabad) representing varying geographical and climatic locations of India. These cities are ranked based on the routine and modified approaches and results are discussed in detail on monthly, seasonal and annual average basis. When the cities are compared only on the basis of comfortable hours, the decreasing order of comfortability is Hyderabad, Kolkata, Delhi, Chennai and Mumbai. However, considering the second methodology, it is revealed that the contribution of uncomfortable hours is greater in Kolkata and Chennai in comparison to Mumbai. The proposed methodology could be an improvement over the current practices and provides a more rational method for relative ranking of cities that could be used for tourism and energy demands.

Clinical and Economic Burden Of Peripheral T-Cell Lymphoma In The United States

BackgroundPeripheral T-cell lymphoma (PTCL) is an aggressive and heterogeneous subtype of non-Hodgkin lymphoma (NHL). PTCL has a poor prognosis due to advanced stage at presentation, and generally poor response to standard chemotherapy. According to recent SEER estimates, PTCL accounts for about 4% of all NHL cases in the United States each year. To date, few studies have assessed the clinical and economic burden of PTCL. MethodsMarketScan data for commercially insured and Medicare supplemental patients were used to retrospectively identify unique PTCL patients. Patients were identified by ICD-9-CM diagnosis codes between October 1, 2007 and June 30, 2011. The time of first PTCL diagnosis code served as the index date, and a second PTCL diagnosis date was used for confirmation. All patients were required to have at least 6 months of continuous enrollment before and 12 months of continuous enrollment after their index date. Patients were excluded if aged <18 years, date of birth or gender were missing, or if they had received a stem cell transplant (SCT) prior to PTCL diagnosis. The control group includes patients that may have any other malignant (excluding PTCL) or non-malignant condition and are considered to represent an average insured patient population from the payer perspective. The control group was matched based on age, sex, region, plan type, payer type, and length of enrollment. Mean cost per month was measured and annualized to provide average yearly costs. Healthcare costs included hospitalizations, pharmacy services, office visits, emergency room visits, hospice stays, SCT, and other patient-related costs (lab procedures, radiology procedures, blood transfusions, and other ancillary procedures). ResultsOf 2820 patients with ≥1 PTCL diagnosis, 1000 patients were identified that met all inclusion criteria (mean age 56 years, 58% male), and were matched to the control group. On an average annual basis, PTCL patients were hospitalized more often (0.9 vs 0.1 hospitalizations), and experienced a longer length of stay (6.4 vs 4 days) compared with matched controls. In addition, PTCL patients had a higher utilization of office visits (16.2 vs 4.1 visits), pharmacy services (34.2 vs 11.6 prescriptions), emergency room visits (0.8 vs 0.2 visits), and hospice care (0.6 vs 0.1 stays). PTCL patients also experienced higher comorbidities (mean Charlson Comorbidity Index of 1.72 vs 0.39, as determined at index date). Overall, PTCL patients incurred much higher average annual costs compared with matched patients ($75,934.08 vs $4660.64; Table), driven mainly by hospitalizations (32.2% of overall costs) and pharmacy services (19.6% of overall costs). ConclusionsPTCL is associated with high resource utilization rates and high overall costs. The development of efficacious treatments for PTCL may offer better disease management and may reduce the clinical and economic burden of PTCL. Disclosures:Potashman:Millennium: The Takeda Oncology Company: Employment. Burudpakdee:Millennium: The Takeda Oncology Company: Consulting researcher Other. Wang:Millennium: The Takeda Oncology Company: Consulting researcher Other, Research Funding. Zhu:Millennium: The Takeda Oncology Company: Employment. Carson:Millennium: The Takeda Oncology Company: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Spectrum, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding; Kyowa Hakko Kirin Pharma, Inc.: Research Funding.