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2661. [Article] Identification of young homemakers' management problems related to resource limitations
This study was designed to identify young homemakers' management problems and to see if limitations of selected resources caused problems. Sources used for current homemaking information were also explored. The ...Citation Citation
- Title:
- Identification of young homemakers' management problems related to resource limitations
- Author:
- Koza, Mary Speckhart
This study was designed to identify young homemakers' management problems and to see if limitations of selected resources caused problems. Sources used for current homemaking information were also explored. The sample was composed of 50 married homemakers, age 30 or under, who were living with their husbands. Homemakers were randomly selected from a newsletter mailing list. Thirty of the homemakers were classified as full-time homemakers. Twelve were employed full-time and six on a part-time basis. Only two were currently enrolled as students taking credit courses. Their average age was 26 years and they had completed a mean of 14 years of education. All but seven had families ranging from one to four children. The family mean income was $10,500. All 17 tasks studied were carried out most often on a regular or sometimes basis by the homemakers. Tasks included: meal preparation, dishwashing, packing lunches, special food preparation, food preservation, regular house care, special house care, upkeep of the home, washing, ironing, sewing and mending, physical care of adults, physical care of children, financial planning, record keeping, marketing for food and marketing for clothing. Homemakers rated tasks on a scale ranging from very simple to very complex. Upkeep of the home was listed as most complex while dishwashing was named the least complex task. Hypothesis 1. Hypothesis 1, management problems of young homemakers will not differ with respect to: length of marriage, age, type of housing, place of residence, homemakers' education, homemakers' occupation, composition of family and income, was accepted since there was no indication of relationship at the 0.10 level of signficance between management problems expressed and the demographic variables. If tasks were complex, homemakers were asked if one or more of six resource limitations including: money, time, knowledge, equipment, energy or space caused the complexity. Chi-square tests indicated that resources were unevenly distributed among the tasks. Limitations causing the most difficulty were time followed by money and knowledge. Resource limitations were unevenly distributed for special food preparation, financial planning, record keeping, marketing for food, marketing for clothing and special house care at the 0.005 significance level. Limitations were unevenly distributed at the 0.01 signficance level for ironing, the 0.05 significance level for food preservation and 0.10 significance level for upkeep of the home. Hypothesis Z. Hypothesis 2, there will be no relationship between the expressed problem areas and the limitations of resources of time, money, knowledge, equipment, energy or space, was rejected for the tasks mentioned above due to the uneven distribution at the stated signficance levels. The task enjoyed most by homemakers was physical care of children even though it took the most time. Dishwashing was least enjoyed, while ironing and packing lunches were least time consuming. The most energy was spent on special house care while washing took the least amount. Sixty-two percent of the homemakers followed daily routines while three-fourths of the homemakers made spending plans regularly. Sixty-eight percent had monetary resources to cover expenditures on a regular basis. Appliances available to all homemakers included a refrigerator or refrigerator-freezer, range and vacuum cleaner. Two-thirds of the families owned or were buying their homes. Twenty-eight felt they could use additional living space. Of these 28, 17 specified the need for at least one additional bedroom. All homemakers received current homemaking information from the Oregon State University Cooperative Extension Service Young Homemaker Newsletter. They requested additional information on community resources, use of personal energy, time, money, household space and equipment via, the newsletter. The majority of homemakers were managing the tasks and resources discussed in this study effectively in terms of the homemakers' satisfactions. The homemakers appeared to place a high value on their dual roles as wife and mother and were willing to try new ideas to enhance their roles.
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2662. [Article] Weed, water, and nutrient management practices for organic blackberry during establishment
The study was conducted in an organic trailing blackberry (Rubus L. subgenus Rubus, Watson) planting established at the North Willamette Research and Extension Center in Aurora, OR on 26 May 2010. Three ...Citation Citation
- Title:
- Weed, water, and nutrient management practices for organic blackberry during establishment
- Author:
- Harkins, Renee H.
The study was conducted in an organic trailing blackberry (Rubus L. subgenus Rubus, Watson) planting established at the North Willamette Research and Extension Center in Aurora, OR on 26 May 2010. Three weed management systems were compared for 'Marion' and 'Black Diamond': 1) non-weeded; 2) hand-hoed two to three times per year (hand weed); and 3) black landscape fabric mulch (weed mat). The planting was certified organic in May 2012, the first fruiting year. Aboveground weed dry weight (DW) increased from 2010 through 2012 in the non-weeded plots. Findings suggest that nitrogen (N) was the major nutrient affecting blackberry cane growth and fruit development. Other nutrients were considered sufficient as evidenced by soil and plant tissue testing, with the exception of calcium (Ca) and boron, which were at the low end of the sufficiency range in some soil and tissue samples. Soil nutrients fluctuated a small amount by distance and location relative to the emitter and sampling depth. However overall nutrient concentrations were adequate for good blackberry growth. Given some of the observed nutrient trends, soil sampling should be completed in-row, under the drip emitters where fertilizer is applied, at a 0.15 cm depth, to ensure proper long-term soil management. Total aboveground plant biomass increased from 0.3 and 2.0 t·ha⁻¹ in the non-fruiting years (2010 and 2011, respectively) to 3.4 t·ha⁻¹ in the fruiting year (2012). Primocane number and plant DW were not affected by cultivar or weed management in 2010. In 2011, 'Black Diamond' had shorter primocanes and less biomass and macro- and micro-nutrient accumulation than 'Marion'. Plants grown without weed control produced fewer but longer primocanes with less biomass and lower nutrient content. In 2012, floricane biomass removed at pruning was greater for ‘Marion’ plants and was least for plants in non-weeded plots, and greatest for plants in weed mat plots. Floricanes had greater macro- and micronutrient concentrations than the primocanes, but less than when the floricane leaves were sampled in July, indicating nutrient loss to the fruit and possibly remobilization of some nutrients during cane senescence. Ultimately, floricanes were also a sink for nutrients, reducing primocane biomass in 2012. During the first harvest year (2012), the cultivars did not differ in the DW yield, however, 'Black Diamond' had a greater fresh yield than 'Marion' (6.0 kg·plant⁻¹ and 5.2 kg·plant⁻¹, respectively). The proportion of above-ground DW biomass allocated to fruit in weed controlled plots averaged 40% in 'Marion' and 56% in 'Black Diamond', suggesting a greater yield efficiency of 'Black Diamond' plants. Non-weeded plots produced approx. half the fresh yield (3.65 kg·plant-1), 39% of the fruit DW biomass as weed mat plots, and the treatment had fruit with lower moisture content, higher percent soluble solids, and lower Ca concentrations, than the other treatments. Net gain of N averaged 41 kg·ha⁻¹ with weed control compared to 25 kg·ha⁻¹ without weed control. Both cultivars accumulated large quantities of N, potassium, and Ca for growth and yield. Nutrient gains may have exceeded fertilizer nutrients available in the fruit production year. Overall, cultivar and weed management strategies had inconsistent effects on tissue and soil nutrient status during the study, with the exception of N. 'Black Diamond' and 'Marion' performed similarly across all three weed management strategies and appeared well suited to organic production for high-value processed markets. Weed mat appeared best suited for organic systems, reducing labor required for weed control, enhancing nutrient uptake by plants, and producing the greatest amount of plant growth and yield. Weed management strategies affected nutrient accumulation and loss, indicating fertilization may need to be adjusted depending on the strategy used.
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2663. [Article] Impacts of Swiss needle cast on Douglas-fir tree-ring stable isotopes and tree carbohydrate reserves
Understanding the mechanisms of disease in forest pathology is a critical component to learning how to most efficiently manage tree diseases like Swiss needle cast (SNC). SNC is an economically important, ...Citation Citation
- Title:
- Impacts of Swiss needle cast on Douglas-fir tree-ring stable isotopes and tree carbohydrate reserves
- Author:
- Saffell, Brandy J.
Understanding the mechanisms of disease in forest pathology is a critical component to learning how to most efficiently manage tree diseases like Swiss needle cast (SNC). SNC is an economically important, fungal disease of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) that is prevalent in coastal areas of the Pacific Northwest. This thesis research provides two contributions to the greater understanding of the pathogenic impacts on plant physiological functioning, or pathophysiology, of SNC on Douglas-fir that will ultimately inform management decisions in Pacific Northwest forests affected by SNC. The primary objectives of this thesis research were: (1) to examine the effects of SNC on Douglas-fir tree-ring stable isotope discrimination of carbon (Δ¹³C) and oxygen (δ¹⁸O) and (2) to evaluate the impact of SNC on tree carbohydrate reserves. Thesis Objective 1- I used growth measurements and stable isotopes of carbon and oxygen in tree-rings of Douglas-fir and a non-susceptible reference species (western hemlock, Tsuga heterophylla (Raf.) Sarg.) to evaluate their use as proxies for variation in past SNC infection, particularly in relation to potential explanatory climate factors. Trees were sampled from a site where a fungicide trial took place from 1996 to 2000, which enabled the comparison of years when disease was present and absent, relative to untreated trees which had the infection throughout. Tree-ring Δ¹³C of treated Douglas-fir increased during the treatment period, and was ~1.6 per mil greater than that of untreated Douglas-fir at the end of the years of the fungicide treatment. Both annual growth and tree-ring Δ¹³C increased with treatment such that treated Douglas-fir had values similar to co-occurring western hemlock during the treatment period, which suggests that the use of Δ¹³C in Douglas-fir tree-rings to track SNC disease history may be a practical approach provided a reference species is available to develop a parallel Δ¹³C chronology. There was no difference in tree-ring δ¹⁸O between treated and untreated Douglas-fir. Tree-ring Δ¹³C of diseased Douglas-fir was negatively correlated with relative humidity (RH) during the two previous summers, consistent with increased leaf colonization by SNC under high humidity conditions that then lead to greater disease severity in following years. Thesis Objective 2- The effects of SNC on Douglas-fir carbohydrate reserves were explored to evaluate the extent to which non-structural carbohydrate (NSC) can be mobilized under natural conditions of low water stress and restricted carbon supply in relation to potential demands for growth. Concentrations of starch, sucrose, glucose and fructose were analyzed in twig wood, foliage, and trunk sapwood of 15 Douglas-fir trees expressing a gradient of SNC symptom severity. There were significant negative relationships between disease severity and growth (mean basal area increment, BAI), as well as between disease severity and mean concentration of trunk NSC. The amount of NSC per unit growth (mean NSC/BAI), an index of the relative priority of storage versus growth, increased with disease severity in all three sampled tissues. These results suggest that under reduced carbon supply with SNC, Douglas-fir trees retain NSC at the expense of growth. The crown retains the most NSC, presumably to maintain foliage growth in the spring to compensate for SNC-induced rapid foliage loss in the summer and fall.
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2664. [Article] Genetic and environmental differences in age at first estrus and in wool and lamb production of crossbred ewe lambs
Genetic and environmental factors affecting age of first estrus, wool production, reproduction and lamb production were examined in eight groups of crossbred ewe lambs from two birth years. The 399 ewe ...Citation Citation
- Title:
- Genetic and environmental differences in age at first estrus and in wool and lamb production of crossbred ewe lambs
- Author:
- Cedillo, Rose Mary
Genetic and environmental factors affecting age of first estrus, wool production, reproduction and lamb production were examined in eight groups of crossbred ewe lambs from two birth years. The 399 ewe lambs whose first year production was analyzed were from eight crossbred groups resulting from mating North Country Cheviot, Dorset, Finnsheep and Romney rams to Suffolk or whiteface Columbia-type range ewes. The ewe lambs were born January through March of both 1973 and 1974, and were raised to weaning on western Oregon hill pastures. They were summered and maintained through the breeding season on irrigated pastures. At the end of the breeding season each year, ewes within each of the eight groups were randomly divided between hill pasture and irrigated valley pasture management systems. After lambing in common facilities, they were returned to the appropriate management environment where they remained throughout lactation. Average age at first estrus for the 90 percent of ewes which did cycle their first fall was 205 days. Age at estrus between years differed by 18 days (P<.01). Sire breed and the sire x dam breed interaction were not significant effects, but ewes with Suffolk dams cycled ten days earlier than ewes with Columbia dams (P<.01). Also a greater proportion of ewes with Columbia dams failed to cycle their first fall (18 percent versus 2 percent for ewes with Suffolk dams). None of the birth year interactions was significant. The regression of age at estrus on birth date of ewe was -.85 days per day (P<.01). The regression of age at estrus on ewe weight at first estrus (estimated by interpolation between bracketing weights) was 0.39 days per pound (P<.01). The unexpected signs of the two regression coefficients probably resulted from shortened day length in the fall triggering estrus at a fairly constant calendar time but at varying ages and weights, depending upon when the lamb was born the previous spring lambing season. Breed of the ewe's dam significantly affected wool grade with Columbia crosses having finer wool. Staple length was longest and about equal for Finn and Romney sired ewes; Dorset crosses produced the shortest wool. Columbia cross wool was longer than Suffolk cross wool only in Finn and Dorset cross ewes. Grease fleece weight of Columbia crosses was consistently heavier than that of Suffolk crosses. Romney sired ewes had the heaviest fleeces followed by Cheviot, Dorset and Finn sired ewes. Observable medullation was most severe in the two Cheviot crossbred groups, with a tendency for slightly greater medullation in Suffolk than in Columbia crosses. Romney x Columbia ewes generated the most wool income, due to heavy fleece weight and high value per pound of clean wool. Ewes with Columbia dams generated higher wool income than did those with Suffolk dams. The reproductive performance of ewes with Finn sires was superior to that of ewes with Dorset, Cheviot or Romney sires, while ewes with Suffolk dams were superior to ewes with Columbia dams. Finn crossbreds had the greater percentage of ewes lambing per ewe bred (72 percent), while Romney x Columbia ewes were lowest (18 percent). Finn sired crossbred ewes averaged 1.62 lambs born per ewe lambing compared to 1.18 for the average of the other crosses. Finn cross ewes excelled for total weight of lamb weaned, followed by Dorset, Cheviot and Romney sired ewes. The greater lamb production of the Suffolk cross ewes more than compensated for their lower wool production. They generated $6.00 more total gross income than did Columbia crosses. Also for gross income, ewes with Finn sires were highest followed by Dorset, Cheviot and Romney sired ewes.
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2665. [Article] Carbon Dynamics in Response to Land Cover Change in Tropical Peatlands, Kalimantan, Indonesia
This study focuses in providing the knowledge on carbon (C) stocks, emission and ecosystem productivity related to land use/land cover change in tropical peatlands. The field research activities were ...Citation Citation
- Title:
- Carbon Dynamics in Response to Land Cover Change in Tropical Peatlands, Kalimantan, Indonesia
- Author:
- Basuki, Imam
This study focuses in providing the knowledge on carbon (C) stocks, emission and ecosystem productivity related to land use/land cover change in tropical peatlands. The field research activities were conducted for about 17 months between August 2013 to December 2015, at Pematang Gadung peat dome (peat depth up to 10.5 m), Ketapang Regency, West Kalimantan, Indonesia. The objectives of this study were: a). to quantify C stocks of tropical coastal peat swamp forest, and the potential impact of forest degradation due to draining and logging activities on the forest’s carbon stocks; b). to examine the change in ecosystem C stocks and the potential C emissions in relation to land conversion from intact peat swamp forest (PSF) to logged peat forest (LPSF), early seral (ES) and oil palm plantation (OP); and c). to estimate net primary production (NPP) and net ecosystem production (NEP) in peat swamp forests, logged peat forest, early seral and smallholder - oil palm plantations. The intact peat forest sites have higher total aboveground C stocks (125 Mg C ha-1) than the logged peat forest sites (77 Mg C ha-1). Mean depths of the LPSF was 725 cm and the PSF was 915 cm (p= 0.06). Mean peat carbon stocks at PSF was 4,243 Mg C ha-1, higher than at LPSF that was 3,675 Mg C ha-1. Logging and draining had reduced the biomass of trees and the peat carbon pools. My study demonstrated that tropical coastal PSF has the largest total carbon stocks among terrestrial ecosystems on earth. The large carbon stocks and high rates of PSF degradation, points to the relevance for inclusion of PSF in nationally appropriate climate change mitigation and adaptation strategies. The mean ecosystem carbon stock for the PSF sites was 4,401 Mg C ha-1. Ecosystem C stocks of LPSF, ES and OP was 3,768, 3,147, and 3,442 Mg C ha-1, respectively. PSF stocks was significantly higher than the degraded land covers. At all sites, soils comprised > 96% of the mean ecosystem carbon stock. Using the estimation based on ecosystem carbon loss to total peat depths, the conversion of PSF to LPSF, ES and OP was estimated to result in a net loss of 1,982, 4,259 and 3,176 Mg C-CO2 ha-1, respectively. My results confirm that land cover change significantly impacted soil properties and reduced ecosystem carbon stocks. The tropical peatlands need urgent and significant efforts in conservation and restoration, to regain its function as a C sink and mitigate climate change. I found that land use/land cover change resulted in large shifts in NPP and NEP. LPSF, ES and OP have significantly lower NPP (11.1 Mg C ha-1 yr-1, 10.8 Mg C ha-1 yr-1 and 3.7 Mg C ha-1 yr-1, respectively) than PSF (13.2 Mg C ha-1 yr-1). ES showed lower heterotrophic respiration (30.7 Mg CO2 ha-1 yr-1) than PSF, LPSF and OP (37.7 Mg CO2 ha-1 yr-1, 40.7 Mg CO2 ha-1 yr-1, 38.7 Mg CO2 ha-1 yr-1, respectively). LPSF and OP were net carbon sources; they have negative mean NEP values (-0.1 Mg CO2-e ha-1 yr-1 and -25.1 Mg CO2-e ha-1 yr-1, respectively). In contrast PSF and ES were net carbon sinks (10.8 Mg CO2-e ha-1 yr-1 and 9.1 CCO2 ha-1 yr-1, respectively). PSF is among the most productive of terrestrial ecosystems, with an NPP exceeding that of many tropical rain forests and similar to the most productive mangrove ecosystems. I found that land use decreases productivity of the LPSF and OP sites. The ES had a similar NEP to the PSF, but frequent fires in this ecosystem likely offset carbon gains during the fire intervals. Land use change and forest degradation have shifted tropical PSFs from net carbon sinks to net carbon sources. My study demonstrated that land conversion in tropical peat swamp forests should be halted and degraded peatlands need to be restored in order to mitigate climate change.
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In Part I, (4S,5R)-4,5-dimethyl-4-phenylcyclohex-2-enone (19a) was prepared in 73% yield with high enantio- and diastereo-selectivity (er > 98:2, dr > 20:1) on a multigram scale by a Yamada-Otani condensation ...
Citation Citation
- Title:
- Scaffold reactivity and large scale Synthesis of organocatalyzed Yamada-Otani Condensation product and investigation of the synthesis and properties of axially chiral 8,8'-biquinolyls and 8-(naphtha-1-yl)quinolines
- Author:
- Banerjee, Somdev
In Part I, (4S,5R)-4,5-dimethyl-4-phenylcyclohex-2-enone (19a) was prepared in 73% yield with high enantio- and diastereo-selectivity (er > 98:2, dr > 20:1) on a multigram scale by a Yamada-Otani condensation between (E)-pent-3-en-2-one and 2-phenylpropanal catalyzed by a sulfonimide derivative of (S)-proline (18, HuaCat®). Synthetically useful transformations of the cyclohexenone product 19a were demonstrated, as follows: (a) alpha-alkylation via Li-enolate formation (e.g., LDA, DMPU, MeI, THF, –78 °C, 2 h; 86% yield, dr > 20:1), (b) 1,2-addition of organolithiums (e.g., PhLi, THF, –78 °C, 2 h; 82% yield, dr > 20:1), and (c) 1,4-addition of cyanocuprates (e.g., n-BuLi, CuCN, THF, –78 °C, 2 h; 90% yield, dr > 20:1). In Part II, an azaanalog of 1,1´-bi-2-naphthol (BINOL, 38), 7-hydroxy-8-(2-hydroxynaphth-1-yl)quinoline (8-azaBINOL, 67), was prepared in 3 steps and 49% yield from N,N-diethyl O-(7-hydroxy-8-iodoquinolyl) carbamate via Suzuki coupling with 1-naphthyl-boronic acid followed by Sanford oxidation and saponification. 8- AzaBINOL (67) was resolved into (–)-(aS) and (+)-(aR) atropisomers by enzymatic hydrolysis of its racemic divalerate derivative with bovine pancreas acetone powder. The configurational stability of 8-azaBINOL (67) was found to be intermediate to that of 7,7´-dihydroxy-8,8´-biquinolyl ('8,8´-diazaBINOL', 50, least stable) and BINOL (38, most stable). Eyring plot analysis of the enantiomerization kinetics of 50, 67, and 38, in DMSO solution revealed activation parameters of ΔH‡ = +27.4, +19.9, +23.2 kcal mol–1, and ΔS‡ = +3.8, –27.9, –25.3 cal mol–1 K–1, respectively. The unique character of ΔH‡ and ΔS‡ values for biquinolyl 50 suggests that the enantiomerization mechanism for 50 is distinct to that for naphthalenes 67 and 38. Monohydroxy analogs of 67, 7-hydroxy-8-(naphth-1-yl)quinoline (71) and 8-(2-hydroxynaphth-1-yl)quinoline (75), were similarly prepared and their racemization half-lives at rt were determined; τ1/2(rac.) was strongly dependent on solvent for naphthol 75 (τ1/2(rac.) at 24 °C: in CHCl3 = 2.7 h, in MeOH = 89 h) but not for the quinol 71 (τ1/2(rac.) at 24 °C: in CHCl3 = 106 h, in MeOH = 120 h). 8-AzaBINOL (67) and its tosylic acid salt (67•TsOH) were evaluated as potential hydrogen-bonding / Brønsted acid organocatalysts for enantioselective carbon-carbon bond forming processes. Neither form of the compound was an effective catalyst for the Henry reaction between nitromethane and benzaldehyde nor the conjugate addition of acetylacetone to beta-nitrostyrene; however, these quinols did promote the addition of nucleophilic arenes to pyruvate esters (albeit with low enantioselectivity). For example, addition of indole to ethyl trifluoropyruvate (Et2O, –78 °C) gave the expected beta-substituted indole product [(S)-87] in 98% yield and with 5% ee in the presence of free base (S)-67 (10 mol%). The same organocatalyst did not promote addition of indole to ethyl pyruvate (Et2O, –40 °C) but its more reactive tosylate salt (S)-67•TsOH did, resulting in an 82% yield of the addition product with 3% ee. In a collaborative study (with R. Overacker and S. Loesgen), a 45-member library of 8-azaBINOL and 8,8´-diazaBINOL derivatives was evaluated for biological activity in cytotoxicity/cell viability and HIV viral entry inhibition assays. The isopropyl ether of 7-hydroxy-8-(naphth-1-yl)quinoline (92) and the analogous N,N-diethyl carbamate (69) exhibited the most significant bioactivity with respective IC50 = 4.74 μM and 5.18 μM for inhibition of HIV-1 entry into TZM-b1 cells. Comparable 8,8´-diazaBINOLs did not inhibit viral entry. Specific binding of isopropyl ether 92 to purified and immobilized HIV-1 glycoprotein 120 with a KD = 22 ± 2.9 μM was established using biolayer interferometry.
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2667. [Article] Carboxylesterases in the house fly (Musca domestica, L.), flesh fly (Sarcophaga bullata, Park.), and black blow fly (Phormia regina, Meig.)
The carboxylesterases of three species of diptera, the flesh fly (Sarcophaga bullata, Park.), the black blow fly (Phormia regina, Meig.), and the house fly (Musca domestica, L.) were compared in relation to ...Citation Citation
- Title:
- Carboxylesterases in the house fly (Musca domestica, L.), flesh fly (Sarcophaga bullata, Park.), and black blow fly (Phormia regina, Meig.)
- Author:
- Maa, Can-jen William
The carboxylesterases of three species of diptera, the flesh fly (Sarcophaga bullata, Park.), the black blow fly (Phormia regina, Meig.), and the house fly (Musca domestica, L.) were compared in relation to hydrolytic activity against three substrates, response to inhibition and induction, isozyme composition, and age-dependent variation in activity. Similar studies were also conducted with an insecticide-resistant house fly strain. Most of the experiments were with adult female flies but male flies as well as larvae and pupae were included in several experiments. Naphthyl acetate was the substrate common to all experiments and the esterases hydrolyzing this compound were further characterized according to their inhibition by eserine, parahydroxymecuribenzoate (PHNB), and paraoxon. The hydrolytic activity observed in the presence of eserine and PHNB or blocked by paraoxon was considered to be due to carboxylesterases of the B-type. Two other esters, hydroprene, an insect growth regulator similar in structure to the natural juvenile hormone, and juvenile hormone-1, were also used as substrates. Neither the hemolymph nor the cytosol esterases of the three species were susceptible to eserine inhibition, indicating that the samples contained minor quantities of the choline esterases. PHNB had little inhibitory effect on the flesh fly esterases of both hemolymph and soluble fraction. However, this inhibitor reduced the activity of the blow fly esterases by more than 50 percent, indicating a high content of aryl esterases in this species. The house fly esterases were also inhibited by PHNB but to a less extent than those of the blow fly. As expected, paraoxon was a strong inhibitor of the esterases in both hemolymph and soluble fraction of the three species. The total enzyme content of the flies was estimated from the hemolymph volumes determined earlier and the activity per unit volume found in the age-dependency experiments. The daily average activity estimated in this way was highest in the flesh fly, about four times that of the blow fly, and lowest in the house fly, about one-seventh that of the flesh fly. The values were even lower in the case of the resistant house flies, about 1/40th those of the flesh fly. When hydroprene was used as a substrate in the age-dependency experiments, the activity profiles were similar to those found with naphthyl acetate as substrate indicating that the same enzymes were involved in the hydrolysis of this JH analogue. Of the three species, the flesh fly esterases were most active against hydroprene and the blow fly and resistant house fly enzymes were the least active. The flesh fly hemolymph enzymes averaged, on a per-day basis, up to three times more hydroprene cleaving activity than those of the resistant house flies. The electrophorese experiments with hemolymph and cytosol revealed the presence of several carboxylesterase isozymes. As many as 14 different esterase-active bands were found in flesh fly hemolymph, 11 in blow fly hemolymph, and 12 in house fly hemolymph. Similar results were obtained with the cytosol. These bands were placed in five groups according to their mobilities in the poly acrylamide gels and it was evident that the isozymes migrating to the midpoint of the gels were responsible for most of the carboxylesterase activity. Some slow-moving isozymes were also thought to be responsible for this type of activity. Other evidence obtained during the electrophoreses experiments indicated that the isozymes hydrolizing hydroprene were from the same groups as those cleaving naphthyl-acetate while those which attacked JH-1 had different electrophoretic characteristics. Both hydroprene and naphthyl acetate esterases were induced by topically applied hydroprene. The response was dose dependent in the range 1-10 ug for flesh flies and 1-5 ug for house flies and blow flies. However, the response was variable and appeared to depend on the age of the flies at the time of the treatment. Increases in esterase activity ranged from 1.5 to 4-fold with the flesh fly enzymes being the most responsive and those of the blow fly the least. The possibility of JH-1 esterase induction by hydroprene was not investigated.
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2668. [Article] Geochemistry of Plutonic Rocks of the Western Cascades, Washington & Oregon : Relationship to Crustal Segmentation and Ore Genesis
The volcanic (~45-10 Ma) and plutonic rocks (~37-12 Ma) comprising the Western Cascades extend from northernmost California to southern British Columbia and are ancestral to modern arc magmatism. The ancestral ...Citation Citation
- Title:
- Geochemistry of Plutonic Rocks of the Western Cascades, Washington & Oregon : Relationship to Crustal Segmentation and Ore Genesis
- Author:
- Utevsky, Elinor S.
The volcanic (~45-10 Ma) and plutonic rocks (~37-12 Ma) comprising the Western Cascades extend from northernmost California to southern British Columbia and are ancestral to modern arc magmatism. The ancestral arc hosts a series of small plutons that are locally associated with porphyry (Cu-Mo) and epithermal (Au) ore deposits. Three crustal segments identified by Schmidt et al. (2008, 2013) in the modern arc are potentially reflected in the geochemistry of the ancestral Cascades as well: Paleozoic-Mesozoic accreted terranes, metamorphic rocks, and granites to the north; thin Paleocene Siletzia oceanic crust of the Columbia Embayment in the center; and Paleozoic-Mesozoic ultramafic sheets and marine arc-related volcanic and sedimentary rocks of the Klamath Terrane to the south. Therefore, the Western Cascades of Washington and Oregon provide a field laboratory to examine the chemical compositions and ages of granitoid intrusions associated with a variety of magmatic-hydrothermal ore deposits, and to compare the compositions with the along-arc variation of the age, composition and thickness of the underlying crust. The majority of the 15 new zircon U-Pb ages reported in this study are 27 to 12 Ma with the exception of the ~37 Ma Snoqualmie North Fork intrusions of central WA. A total of 610 zircons were analyzed, of which 118 have ages older than the main population and are considered to be xenocrystic or inherited. The north segment contains the oldest (up to 67 Ma) and most continuous inherited population. The absence of inherited grains older than 67 Ma suggests that neither the North Fork nor White River districts overlie old crystalline crust, but instead overlie Paleocene-Eocene volcanics that are the likely source of inherited zircons. Districts of the Columbia segment have sparse inherited zircon populations (n = 38 of 350 total), ranging from 54 to 20 Ma. The dearth of inherited zircons in the center of the arc suggests limited contamination by a source no older than 55 Ma, likely the dominant Eocene sources of detrital zircon found within the Tyee Formation. Districts overlying the Klamath Terrane have slightly more substantial inherited zircon populations than districts overlying Siletzia but still decidedly few inherited grains (a total of 25 out of 85 grains analyzed, ranging from 44 to 19 Ma); these grains are likely sourced from similar contaminants to those underlying the central segment of the arc, instead of from accreted Mesozoic rocks of the Klamath Terrane. The hypabyssal plutonic rocks represent a small area (~1%) of exposures in the Western Cascades, and range in composition from diorites to granodiorites and minor granite. Fe-Ti oxides, where preserved, include magnetite and ilmenite in proportion of ~2:1, and together with presence of hornblende and biotite are suggestive of modest oxidation states of ~ ΔNNO of 0 to 1 (Carmichael & Nicholls, 1967). Abundant hornblende is observed in 31 of 36 available petrographic sections. Ba/Nb values are not obviously correlated with SiO₂ content from any given district, but tend to increase at any given SiO₂ content from north to south. Th/Ta ratios notably increase with SiO₂, and are lowest in the mid-latitude districts (North Santiam, Detroit Dam, Quartzville, and Blue River). While increased slab fluid could increase Ba relative to Nb, the greater abundance of Ba, Th, and Th/Ta southward at given SiO₂ are more consistent with an increased role of crustal contamination. Dy/Yb ratios decrease with increasing SiO₂ contents with the exception of the North Fork District. V/Sc ratios decrease with increasing SiO₂ with the exception of samples of the Spirit Lake Pluton, and slightly increase from south to north at any given SiO₂ content. Zircons in the Western Cascades plutonic rocks have characteristically large negative Eu anomalies (Eu/Eu* < 0.5) and small positive Ce anomalies, correlated with relatively reduced oxidation states and low water contents, even when directly associated with moderately economic porphyry Cu deposits. Although these magmas are sufficiently water-rich to abundantly crystallize and fractionate amphibole (at least 3 wt. % H₂O), it is evident that plagioclase likely crystallized early and was not suppressed by high water contents (> 3 wt. % H₂O). There is no evidence that Western Cascade magmas were strongly oxidized (> NNO +1). Although crustal thickness is poorly constrained in the north and south segments, it is evidently variable along-arc (and may thicken slightly to the south), but is likely relatively thin. I therefore suggest that crustal thickness and lithology substantially control ore potential within the Western Cascade Arc.
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There is growing commercial interest in the use of unmanned aerial vehicles (UAVs) in urban environments, specifically for package delivery applications. However, the size, complexity and sheer numbers ...
Citation Citation
- Title:
- Adaptive Multiagent Traffic Management for Autonomous Robotic Systems
- Author:
- Rebhuhn, Carrie
There is growing commercial interest in the use of unmanned aerial vehicles (UAVs) in urban environments, specifically for package delivery applications. However, the size, complexity and sheer numbers of expected UAVs makes conventional air traffic management that relies on human air traffic controllers infeasible. To enable UAVs to safely and efficiently operate in congested environments, it is essential to develop autonomous UAV management strategies. We introduce a dynamic hierarchical traffic control model that reacts to traffic conditions instantaneously to reduce congestion in the airspace. An obstacle-filled airspace lends itself to a modelling as a graph structure similar to a road network. We introduce controller agents, which set costs across the airspace. These agents control traffic similarly to adaptive metering lights in highway traffic. UAVs then plan their paths based on the costs (e.g. conflicts, or delays) they see for traversing particular parts of the airspace. This provides us a decentralized method for reducing traffic in an airspace Our hierarchical structure allows us to separate the traffic reduction problem from the individual robot navigation problem. Each robot does not explicitly coordinate with others in the airspace. Instead, robots execute their own individual internal cost-based planner to travel between locations. We then use neuro-evolution to provide incentives to these cost-based planners to reduce traffic in the environment. Traffic quality can be expressed in several different ways. We first evaluate traffic our traffic reduction policies in terms of `conflicts', which characterizes situations where an aircraft comes too close to another for safety in a physical space. We then examine traffic in terms of the amount of `delay' that all agents incur, which assumes that there is a structure to ensure only a safe number of UAVs occupy the same area. Finally, we look at the total travel time that a UAV can expect to take from the moment it enters the airspace until the time it gets to its destination. To facilitate an exploration of the UTM problem without waiting for a full simulation of UAVS running with A* , we develop an abstraction of the UTM domain that preserves the core UTM problem. We then investigate performance under differing levels of traffic, a well as two different agent structures. Our results show similar performance for both agent definitions, with delay reduction of up to 68% in high traffic cases. With a fast version of the UTM problem, we explore the effect of redefining the control structure such that links, or edges of the UTM graph, set costs individually. This shifts the control paradigm toward controlling directional travel rather than areas in the space, as was the case with sector agents used in previous approaches. Due to our graph structure, we find that there are far more control elements in the link agent approach than in the sector agent approach. We identify a tradeoff; link agents give finer control, but the coordination problem for the sector agents is easier because there are fewer sector agents. This indicates that we can improve performance out of a more distributed link-based setup if we address the challenges of multiagent coordination. However, the UAV traffic management domain presents a uniquely difficult coordination problem; each agent's action can affect the perceived value of every other agent's actions. This means that there is an excessive amount of noise in the system, as another agent's action can have a lot of impact on the reward an agent receives. We reduce the amount of multiagent noise by reducing the number of agents that are capable of learning. We identify that some agents have more ability to influence traffic based on the topology and traffic profile of the graph. This metric we call impactfulness. We use this metric to improve the learning by removing less impactful agents from the learning process, making a more stationary system in which the impactful agents can learn. The contributions of this work are to: - Introduce a cost-based traffic management approach that is platform-agnostic and fast to implement. - Develop a multiagent approach to setting costs in this traffic management system that is adaptive to traffic conditions and learns long-term effects of management decisions. - Create an abstraction of UAV traffic that captures key physical attributes, creating a fast and flexible simulation method. - Quantify agent contributions to system performance by experimenting with single agent learning, single agent exclusion, and a sliding number of agents learning in the system.
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2670. [Article] Improving the Roadside Environment through Integrating Air Quality and Traffic-Related Data
Urban arterial corridors are landscapes that give rise to short and long-term exposures to transportation-related pollution. With high traffic volumes, congestion, and a wide mix of road users and land ...Citation Citation
- Title:
- Improving the Roadside Environment through Integrating Air Quality and Traffic-Related Data
- Author:
- Kendrick, Christine M.
- Year:
- 2016
Urban arterial corridors are landscapes that give rise to short and long-term exposures to transportation-related pollution. With high traffic volumes, congestion, and a wide mix of road users and land uses at the road edge, urban arterial environments are important targets for improved exposure assessment to traffic-related pollution. Applying transportation management strategies to reduce emissions along arterial corridors could be enhanced if the ability to quantify and evaluate such actions was improved. However, arterial roadsides are under-sampled in terms of air pollution measurements in the United States and using observational data to assess such effects has many challenges such as lack of control sites for comparisons and temporal autocorrelation. The availability of traffic-related data is also typically limited in air monitoring and health studies. The work presented here uses unique long-term roadside air quality monitoring collected at the intersection of an urban arterial in Portland, OR to characterize the roadside atmospheric environment. This air quality dataset is then integrated with traffic-related data to assess various methods for improving exposure assessment and the roadside environment. Roadside nitric oxide (NO), nitrogen dioxide (NO2), and particle number concentration (PNC) measurements all demonstrated a relationship with local traffic volumes. Seasonal and diurnal characterizations show that roadside PM2.5 (mass) measurements do not have a relationship with local traffic volumes, providing evidence that PM2.5 mass is more tied to regional sources and meteorological conditions. The relationship of roadside NO and NO2 with traffic volumes was assessed over short and long-term aggregations to assess the reliability of a commonly employed method of using traffic volumes as a proxy for traffic-related exposure. This method was shown to be insufficient for shorter-time scales. Comparisons with annual aggregations validate the use of traffic volumes to estimate annual exposure concentrations, demonstrating this method can capture chronic but not acute exposure. As epidemiology and exposure assessment aims to target health impacts and pollutant levels encountered by pedestrians, cyclists, and those waiting for transit, these results show when traffic volumes alone can be a reliable proxy for exposure and when this approach is not warranted. Next, it is demonstrated that a change in traffic flow and change in emissions can be measured through roadside pollutant concentrations suggesting roadside pollution can be affected by traffic signal timing. The effect of a reduced maximum traffic signal cycle length on measurements of degree of saturation (DS), NO, and NO2 were evaluated for the peak traffic periods in two case studies at the study intersection. In order to reduce bias from covariates and assess the effect due to the change in cycle length only, a matched sampling method based on propensity scores was used to compare treatment periods (reduced cycle length) with control periods (no change in cycle length). Significant increases in DS values of 2-8% were found along with significant increases of 5-8ppb NO and 4-5ppb NO2 across three peak periods in both case studies. Without matched sampling to address the challenges of observational data, the small DS and NOx changes for the study intersection would have been masked and matched sampling is shown to be a helpful tool for future urban air quality empirical investigations. Dispersion modeling evaluations showed the California Line Source Dispersion Model with Queuing and Hotspot Calculations (CAL3QHCR), an approved regulatory model to assess the impacts of transportation projects on PM2.5, performed both poor and well when predictions were compared with PM2.5 observations depending on season. Varying levels of detail in emissions, traffic signal, and traffic volume data for model inputs, assessed using three model scenarios, did not affect model performance for the study intersection. Model performance is heavily dependent on background concentrations and meteorology. It was also demonstrated that CAL3QHC can be used in combination with roadside PNC measurements to back calculate PNC emission factors for a mixed fleet and major arterial roadway in the U.S. The integration of roadside air quality and traffic-related data made it possible to perform unique empirical evaluations of exposure assessment methods and dispersion modeling methods for roadside environments. This data integration was used for the assessment of the relationship between roadside pollutants and a change in a traffic signal setting, a commonly employed method for transportation management and emissions mitigation, but rarely evaluated outside of simulation and emissions modeling. Results and methods derived from this work are being used to implement a second roadside air quality station, to design a city-wide integrated network of air quality, meteorological, and traffic data including additional spatially resolved measurements with feedback loops for improved data quality and data usefulness. Results and methods are also being used to design future evaluations of transportation projects such as freight priority signaling, improved transit signal priority, and to understand the air quality impacts of changes in fleet composition such as an increase in electric vehicles.