573 research outputs found
A cost-benefit analysis of a pellet boiler with electrostatic precipitator versus conventional biomass technology: A case study of an institutional boiler in Syracuse, New York
BACKGROUND: Biomass facilities have received increasing attention as a strategy to increase the use of renewable fuels and decrease greenhouse gas emissions from the electric generation and heating sectors, but these facilities can potentially increase local air pollution and associated health effects. Comparing the economic costs and public health benefits of alternative biomass fuel, heating technology, and pollution control technology options provides decision-makers with the necessary information to make optimal choices in a given location.
METHODS: For a case study of a combined heat and power biomass facility in Syracuse, New York, we used stack testing to estimate emissions of fine particulate matter (PM2.5) for both the deployed technology (staged combustion pellet boiler with an electrostatic precipitator) and a conventional alternative (wood chip stoker boiler with a multicyclone). We used the atmospheric dispersion model AERMOD to calculate the contribution of either fuel-technology configuration to ambient primary PM2.5 in a 10 km x 10 km region surrounding the facility, and we quantified the incremental contribution to population mortality and morbidity. We assigned economic values to health outcomes and compared the health benefits of the lower-emitting technology with the incremental costs.
RESULTS: In total, the incremental annualized cost of the lower-emitting pellet boiler was 1.7 million annually, greatly exceeding the differential costs even when accounting for uncertainties. Our analyses also showed complex spatial patterns of health benefits given non-uniform age distributions and air pollution levels.
CONCLUSIONS: The incremental investment in a lower-emitting staged combustion pellet boiler with an electrostatic precipitator was well justified by the population health improvements over the conventional wood chip technology with a multicyclone, even given the focus on only primary PM2.5 within a small spatial domain. Our analytical framework could be generalized to other settings to inform optimal strategies for proposed new facilities or populations.This research was supported by the New York State Energy Research and Development Authority (NYSERDA), via an award to the Northeast States for Coordinated Air Use Management (Agreement #92229). The SCICHEM work of KMZ was supported by the Electric Power Research Institute (EPRI)
Petawatt laser absorption bounded
The interaction of petawatt () lasers with solid matter
forms the basis for advanced scientific applications such as table-top particle
accelerators, ultrafast imaging systems and laser fusion. Key metrics for these
applications relate to absorption, yet conditions in this regime are so
nonlinear that it is often impossible to know the fraction of absorbed light
, and even the range of is unknown. Here using a relativistic
Rankine-Hugoniot-like analysis, we show for the first time that exhibits a
theoretical maximum and minimum. These bounds constrain nonlinear absorption
mechanisms across the petawatt regime, forbidding high absorption values at low
laser power and low absorption values at high laser power. For applications
needing to circumvent the absorption bounds, these results will accelerate a
shift from solid targets, towards structured and multilayer targets, and lead
the development of new materials
Opioid Tolerance Influences Outcomes after Lumbar Fusion in Patients with Degenerative Pathology
Introduction: Extended opioid use prior to surgery has been implicated in poorer postoperative outcomes. However, it remains unclear if there is a significant difference in postoperative outcomes among preoperative opioid-naïve and opioid-tolerant patients who undergo lumbar spinal fusion. The purpose of this study was to determine the effect of preoperative opioid use on patient-reported outcome measures in patients undergoing lumbar spinal fusion.
Methods: This retrospective cohort analysis identified 260 patients who underwent lumbar spinal fusion at a high-volume, single institution. There were two cohorts: patients who were opioid-naïve (defined as total opioid consumption of ≤ 7 days in the two months prior to surgery) and opioid-tolerant users (\u3e 7 days). Outcome measures were analyzed via the number of and duration of opioid tablets consumed, and patient-reported outcome measures (ODI, SF-12 PCS and MCS, and VAS Back and Leg pain scores).
Results: Overall, opioid-naïve patients were prescribed significantly fewer tablets on average compared to opioid-tolerant users. The number of tablets prescribed prior to surgery was a predictor for prolonged opioid use—defined as greater than one script after surgery. Opioid-tolerant users had decreased improvement in outcomes postoperatively compared to opioid-naïve users.
Discussion: This study suggests that preoperative opioid-tolerant usage was associated with worse outcome scores postoperatively. Opioid-tolerant users were found to have significantly more pain medication tablets preoperatively and for a longer duration postoperatively. Therefore, opioid-tolerant usage can adversely affect patient outcomes and is a modifiable risk factor prior to undergoing lumbar spinal fusion
Rentabilidade de diversas espécies agrícolas durante o estabelecimento de sistemas agroflorestais agroecológicos
TCC(graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Biológicas. Biologia.A adoção de sistemas agroecológicos por agricultores ainda ocorre de maneira lenta, de modo que diferentes estudos apontam aspectos sócio-econômicos entre os principais gargalos contribuindo para isso. O período inicial de implantação destes modelos, neste caso, destaca-se por ser uma fase delicada economicamente ao produtor, uma vez que os gastos são altos e muitas vezes o retorno não. Tendo isso em vista, o presente trabalho procurou comparar a rentabilidade de diversas espécies anuais agrícolas durante o primeiro ano de cultivo de um sistema agroflorestal agroecológico, em São Pedro de Alcântara – SC. Para tal, foram considerados os custos envolvidos com a implantação de 23 espécies, bem como a produtividade e valores de comercialização apresentados por cada uma. Em seguida, foram estimados seus rendimentos líquidos e potencial de recuperação de investimentos. Observou-se, enfim, uma grande variabilidade de rentabilidade entre as espécies. A grande maioria das espécies apresentou uma renda líquida média negativa, de modo que apenas a Capuchinha e a Mandioca obtiveram rendimentos líquidos positivos, suficientes para cobrir o gasto nelas investido. Tais resultados estão diretamente associados à produtividades muito baixas verificadas para cada espécie, e que devem ter ocorrido devido a fatores ambientais locais desfavoráveis à produção, como infertilidade e compactação do solo, bem como um período de seca nos primeiros meses. Além disso, os gastos com mão de obra representaram os maiores custos neste período, e tiveram grande importância para o saldo final. De maneira geral, os resultados verificados são consequência de um período de “aprendizado”, em que se desconhecia a adaptabilidade de cada espécie ao local, bem como de um cenário desfavorável, em que as condições para produção não eram as mais adequadas.The adoption of agro-ecological systems by farmers still occurs slowly, so that different studies point out social-economic issues between the most important bottlenecks contributing for that. The initial establishment period of these models, in this case, stands out for being an economically delicate phase for the producer, once the costs are high and in many occasions the returns aren’t. With that in mind, this study aimed to compare the net income of different annual species during the first year of an agro-ecological agroforestry system in São Pedro de Alcântara/SC. For that, the costs involved with the implantation of 23 species were considered, so as the productivity and marketing values presented by each of them. In sequence, the net income and the investment recovery potential were estimated. With that, a high variability of the net income was observed between the species. Most part of them presented a negative net result, so that only the Garden Nasturtiun and the Cassava obtained positive net results, sufficient to cover their investments. These results are directly linked to the low productivities verified for each species, and they probably were a consequence of adverse local environmental conditions for cultivation, such as soil compression and infertility, so as a dry period in the first months. In addition, the costs with labor represented the main spending’s in this period, and had a great importance for the final balance. Generally, the performances observed can be explained as a result of a “learning” period, in which the adaptability of each species to the location where unknown, so as due to a “conservative” scenario wherein the conditions for production were unfavorable
Functional Outcomes after Lumbar Fusion in Opioid-Tolerant Patients
Introduction: Prolonged opioid use after lumbar fusion surgery is implicated with increased hospital readmissions, higher postoperative pain scores, and longer return to work time. There are several non-modifiable risk factors for postoperative opioid use including socioeconomic status and gender. The purpose of this study was to determine the effects of opioid-tolerance on PROMs and to determine risk factors for prolonged opioid use after lumbar spine surgery.
Method: Using retrospective cohort analysis, patients who underwent lumbar spinal fusion at TJUH were identified and determined to be either opioid-naïve or opioid-tolerant using the Pennsylvania PDMP. Outcomes included number of opioid tablets consumed, duration of time using opioids, and patient-reported outcome measures (ODI, PCS-12, MCS-12, VAS Back, VAS Leg). Univariate and multivariate analysis were used to compare outcomes between the two groups. Logistic regression was used to determine independent predictors for prolonged opioid use which was defined as greater than one postoperative opioid prescription script filled.
Results: A total of 260 patients were included in the final cohort, of which, 138 were opioid-tolerant and 122 were opioid naïve. Opioid-tolerant patients showed decreased improvement in PROMs compared to the opioid-naïve patients (p=0.043). The number of preoperative pills prescribed was a significant predictor for prolonged opioid use after lumbar fusion.
Conclusion: The number of pills prescribed preoperatively was found to be a predictor for prolonged opioid use after lumbar fusion surgery. Overall, our results demonstrated that naïve patients have improved health-related quality of life outcome scores compared to opioid-tolerant patients after lumbar fusion
Impact of hands‐on care on infant sleep in the neonatal intensive care unit
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135460/1/ppul23513_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135460/2/ppul23513.pd
Structural characterization of CYP144A1 - a cytochrome P450 enzyme expressed from alternative transcripts in Mycobacterium tuberculosis.
Mycobacterium tuberculosis (Mtb) causes the disease tuberculosis (TB). The virulent Mtb H37Rv strain encodes 20 cytochrome P450 (CYP) enzymes, many of which are implicated in Mtb survival and pathogenicity in the human host. Bioinformatics analysis revealed that CYP144A1 is retained exclusively within the Mycobacterium genus, particularly in species causing human and animal disease. Transcriptomic annotation revealed two possible CYP144A1 start codons, leading to expression of (i) a "full-length" 434 amino acid version (CYP144A1-FLV) and (ii) a "truncated" 404 amino acid version (CYP144A1-TRV). Computational analysis predicted that the extended N-terminal region of CYP144A1-FLV is largely unstructured. CYP144A1 FLV and TRV forms were purified in heme-bound states. Mass spectrometry confirmed production of intact, His6-tagged forms of CYP144A1-FLV and -TRV, with EPR demonstrating cysteine thiolate coordination of heme iron in both cases. Hydrodynamic analysis indicated that both CYP144A1 forms are monomeric. CYP144A1-TRV was crystallized and the first structure of a CYP144 family P450 protein determined. CYP144A1-TRV has an open structure primed for substrate binding, with a large active site cavity. Our data provide the first evidence that Mtb produces two different forms of CYP144A1 from alternative transcripts, with CYP144A1-TRV generated from a leaderless transcript lacking a 5'-untranslated region and Shine-Dalgarno ribosome binding site
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