Optical properties of absorbing and non-absorbing aerosols retrieved by cavity ring down (CRD) spectroscopy

International audienceApplication of cavity ring down (CRD) spectrometry for measuring the optical properties of pure and mixed laboratory-generated aerosols is presented. The extinction coefficient (?ext), extinction cross section (?ext) and extinction efficiency (Qext) were measured for polystyrene spheres (PSS), ammonium sulphate ((NH4)2(SO4), sodium chloride (NaCl), glutaric acid (GA), and Rhodamine-590 aerosols. The refractive indices of the different aerosols were retrieved by comparing the measured extinction efficiency of each aerosol type to the extinction predicted by Mie theory. Aerosols composed of sodium chloride and glutaric acid in different mixing ratios were used as model for mixed aerosols of two non-absorbing materials, and their extinction and complex refractive index were derived. Aerosols composed of Rhodamine-590 and ammonium sulphate in different mixing ratios were used as model for mixing of absorbing and non-absorbing species, and their optical properties were derived. The refractive indices of the mixed aerosols were also calculated by various optical mixing rules. We found that for non-absorbing mixtures, the linear rule, Maxwell-Garnett rule, and extended effective medium approximation (EEMA), give comparable results, with the linear mixing rule giving a slightly better fit than the others. Overall, calculations for the mixed aerosols are not as good as for single component aerosols. For absorbing mixtures, the differences between the refractive indices calculated using the mixing rules and those retrieved by CRD are generally higher

MECHANISMS FOR ADDRESSING THIRD-PARTY IMPACTS RESULTING FROM VOLUNTARY WATER TRANSFERS

This research uses laboratory experiments to test alternative water market institutions designed to protect third-party interests. The institutions tested include taxing mechanisms that raise revenue to compensate affected third-parties, and a free market in which third-parties actively participate. We also discuss the likely implications of a command-and-control approach in which there are fixed limits on the volume of water that may be exported from a region. The results indicate that there are some important trade-offs in selecting a policy option. Although theoretically optimal, active third-party participation in the market is likely to result in free-riding that may erode some or all of the efficiency gains, and may introduce volatility into the market. Fixed limits on water exports are likely to result in a more stable market, but the constraints on exports will result in lower levels of social welfare. Taxing transfers and compensating third-parties offers a promising balance of efficiency, equity and market stability.Resource /Energy Economics and Policy,

Uji Aktivitas Imunomodulator Fermentasi Teh Rosela Jamur Kombucha Terhadap Proliferasi Sel Limfosit Mencit Galur Balb/c Secara in Vitro

Recently, some research showed that there is an immunomodulator effect in the fermentation of Rosella kombucha mushroom tea and it can be caused by flavonoid and organic acid. The purpose of this research was to show the activity of immunomodulator Rosella kombucha mushroom tea to against the proliferation of lymphocyte cells of Balb/C mice in vitro and to show the dose and length of fermentation that induces highest immunomodulator activity. Kombucha mushroom was fermented for 5 days, 10 days and also 15 days with boiled Rosella tea, water and sugar. The yield of fermentation in the concentration of 6,25; 12,5; 25; 50 and 100 µg/mL were tested on lymphocyte cells proliferation by the MTT Assay. The OD (Optical Density) data obtained was statistically analyzed by nonparametric Friedman test and continuoused by Mann-Whitney test. The result of this research showed that the fermentation of Rosella kombucha mushroom tea has an immunostimulatory activity on lymphocyte cells proliferation with the concentration 6,25; 12,5 and 25 µg/mL in the 10 days and the highest immunostimulatory activity showed by the concentration 25 µg/mL and 10 days of fermentation time

Cloud Condensation Nuclei properties of model and atmospheric HULIS

Humic like substances (HULIS) have been identified as a major fraction of the organic component of atmospheric aerosols. These large multifunctional compounds of both primary and secondary sources are surface active and water soluble. Hence, it is expected that they could affect activation of organic aerosols into cloud droplets. We have compared the activation of aerosols containing atmospheric HULIS extracted from fresh, aged and pollution particles to activation of size fractionated fulvic acid from an aquatic source (Suwannee River Fulvic Acid), and correlated it to the estimated molecular weight and measured surface tension. A correlation was found between CCN-activation diameter of SRFA fractions and number average molecular weight of the fraction. The lower molecular weight fractions activated at lower critical diameters, which is explained by the greater number of solute species in the droplet with decreasing molecular weight. The three aerosol-extracted HULIS samples activated at lower diameters than any of the size-fractionated or bulk SRFA. The Köhler model was found to account for activation diameters, provided that accurate physico-chemical parameters are known

PERANAN PEMBELIAN JUST IN TIME SEBAGAI ALAT BANTU DALAM MENGURANGI BIAYA PERSEDlAAN PT"X"SURABAYA

Perusahaan hams mcmilikl stararegi agar dapat rnempertahankan araupun mcoingkatkan posisi pasamyn, dengan earn menghasilkan produk yang inovatit: bennutu tinggl dengan biaya semmimal mungklf1 Hal ini dlwujudkan mcialUi kerjasama dan pCr'dfl dari selumh fungst dalam pemsahaall, diantanmya melalui peran fungsi pembehan, untuk Itu diperlukan suatu teknologl unluk mempertinggi efisicnSl dan cfekttvltas fungsi pernbehan, salah sattmya melahll pembelian /1<," m time. Pcrnbclian just m lime mcrupakan pClljaduaian pcngada.'1n harang dcngan cara sedemikian mpa sehingga dapUf ddakukall pcnyerahal! segera lIJltuk memenuhi permintaan ma« penggunaao. Tujuan utama pcmbehan ju.\'1 In wne adalah mcnghilangkan pemborosan dan kOllsisten dalam menmgkatkun prouukti"itas. Penelitian dtlakukan terhadap PT ""X' Surabuya yang hergerak di bidang indu~tfl pembuatan sandai dan sepatu_ Pcnditlal1 yang. digunakan mempakan penelitian kualitatif yang berslfal deskriptif dimana penulis akan rnel1ggambarkan :>eeara siSlcmatis segaia fcnomena aktivitas pcmbelian daiam perusahaan kemudian mencoba mendeskripsikan aktivltas pembehan just HI lime Lila dtterapkan dalam PT "X" Surdbaya dan menelusuri peranannya ternadap blaya pe[scdlaan nahan baku Simpulan yang bisa dlambii dari peneii1ian mi adalah bahwa pembehan JUSI m tlme berperan dalam mengurang:l bmya persedman banan baku PT "X" dan berdampak pacta pernitlmgan biaya pruduksi yang cenderung leblh rcndah danpada sebe\umnya. persediaan bahan baku nol, serta inl'l!ntory lUmm er yang Icbih ccpat dibaudlllgkan sebelumnya

Integrating ecosystem benefits for sustainable water allocation in hydroeconomic modeling

The increasing concern about the degradation of water-dependent ecosystems calls for considering ecosystems benefits in water management decision-making. Sustainable water management requires adequate economic and biophysical information on water systems supporting both human activities and natural ecosystems. This information is essential for assessing the impact on social welfare of water allocation options. This paper evaluates various alternative water management policies by including the spatial and sectoral interrelationships between the economic and environmental uses of water. A hydroeconomic model is developed to analyze water management policies for adaptation to reduced water availability in the Ebro Basin of Spain. The originality in our contribution is the integration of environmental benefits across the basin, by using endemic biophysical information that relates stream flows and ecosystem status in the Ebro Basin. The results show the enhancement of social welfare that can be achieved by protecting environmental flows, and the tradeoffs between economic and environmental benefits under alternative adaptation strategies. The introduction of water markets is a policy that maximizes the private benefits of economic activities, but disregards environmental benefits. The results show that the current institutional policy where stakeholders cooperate inside the water authority, provides lower private benefits but higher environmental benefits compared to those obtained under water markets, especially under severe droughts. However, the water authority is not allocating enough environmental flows to optimize social welfare. This study informs strategies for protection of environmental flows in the Ebro Basin, which is a compelling decision under the imminent climate change impacts on water availability in coming decades

Relation between eating evoked by lateral hypothalamic stimulation and tail pinch in different rat strains

The similarity between the behaviors evoked by tail pinch (TP) and electrical stimulation of the lateral hypothalamus (ESLH) has been noted by many investigators. Evidence is presented for a possible inverse relationship between the probability that ESLH would evoke eating and the readiness to eat in response to TP in six different rat populations (High and Low lines of the LC1 and LC2 Hebrew University Strains, Sprague--Dawley, and Long--Evans). Discussion of these results emphasizes differences in intensity between ESLH and TP stimulation and differences in emotionality among rat populations.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24047/1/0000296.pd

Hydroeconomic modeling for assessing water scarcity and agricultural pollution abatement policies in the Ebro River Basin, Spain

Water scarcity and water quality degradation are major problems in many basins across the world, especially in arid and semiarid regions. The severe pressures on basins are the consequence of the intensification of food production systems and the unrelenting growth of population and income. Agriculture is a major factor in the depletion and degradation of water resources, and contributes to the emissions of greenhouse gases (GHG). Our study analyzes water allocation and agricultural pollution into watercourses and the atmosphere, with the purpose of identifying cost-effective policies for sustainable water management in the Ebro River Basin (Spain). The study develops an hydroeconomic model that integrates hydrological, economic and water quality aspects, capturing the main spatial and sectoral interactions in the basin. The model is used to analyze water scarcity and agricultural pollution under normal and droughts conditions, providing information for evaluating mitigation and adaptation policies. Results indicate that drought events increase nitrate concentration by up to 63% and decrease water availability by 42% at the mouth of Ebro River, highlighting the tradeoffs between water quantity and quality. All mitigation and adaptation policies reduce the effects of climate change, improving water quality and reducing GHGs’ emissions, thus lowering environmental damages and enhancing social well-being. Manure fertilization and optimizing the use of synthetic fertilizers are important cost-effective policies increasing social benefits in a range between 50 and 160 million Euros. Results show that irrigation modernization increases the efficient use of nitrogen and water, augmenting social benefits by up to 90 million Euros, and enlarging stream flows at the river mouth. In contrast, manure treatment plants reduce private and social benefits even though they achieve the lowest nitrate concentrations. Our study provides insights on the synergies and tradeoffs between environmental and economic objectives. Another finding is that drought conditions decrease the effectiveness of policies, and increase the tradeoffs between water availability and nitrate pollution. The results contribute to the discussion of designing cost-effective policies for the abatement of agricultural polluting emissions into water and the atmosphere