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Effect Of Cooking And Packaging Methods On Consumer Acceptability And Shelf-Life Of Ready-To-Eat Gulf Brown ShrimpKamadia, Vimal Vinodchandra 10 December 2010 (has links)
Shrimp is the most valued shellfish product in the United States, and is highly perishable with post mortem metabolic changes that are deteriorative to its shelf-life. The objective of this research was to utilize GC-MS Gas Chromatography-Mass Spectrometry (GC-MS), Gas Chromatography Olfactometry (GCO), and sensory analysis to determine if the relationships exist between consumer acceptability, sensory descriptors and shelf-life of ready-to-eat shrimp. Three different cooking and packaging treatments were utilized: 63°C/15 s, 85°C/5 min, and 93°C/5 min for vacuum, MAP and aerobic packaging treatments, and stored at 2°±1 for 1, 3, 5, 6, 10, 15, 25, and 50 days or until the product was found unacceptable by a trained sensory panel. For Consumer acceptability (Day 3), the 85°C vacuum and 85°C MAP (Modified Atmosphere Packaging) shrimp were preferred (P < 0.05) over other treatments that were evaluated. The aroma active compounds that were identified using GC-MS and GCO consisted of one amine (trimethylamine), five aldehydes (3-methyl butanal, pentanal, hexanal, heptenal, geranial), one organic acid (butyric acid), two sulfur containing compounds (methional, dimethyltrisulfide), one pyrazine (methyl pyrazine) (amine), two alcohols (2-nonen-1-ol, 4 ethyl guaiacol), and one hydrocarbon (camphene). Results showed that for most of the packaging-temperature combinations, even beyond Day 25, the MAP product had fewer compounds and odors associated with spoilage than the aerobic and vacuum packaged products. This was consistent with the descriptive analysis data for which both the 85°C MAP and 93°C MAP treatment products had a longer shelf-life than vacuum treatment products, which had shelf-lives of 15 to 21 Days. The shelf-life of the cooked RTE shrimp that was MAP packaged and cooked at either 85°C or 93°C was between 39 and 42 Days at 2°C. Research indicates that processors of medium gulf brown shrimp could utilize 85°C/5min with MAP due to the shelf-life of the product and the elevated pleasantness scores when compared to the 93°C/5min treatment throughout the shelf-life of the product.
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Use Of Whey-Based Edible Coatings as Antioxidative and Antimicrobial AgentsWeerasinghe, Sashie 11 August 2012 (has links)
Edam and Cheddar whey were thermized (T) for different time periods (5–30 min) at 70 degrees Celsius, vacuum evaporated, and spray dried to obtain whey powders (WP). Native and thermized WP were evaluated for antioxidative properties. Edam and Cheddar WP significantly reduced thiobarbituric acid-reactive substances (TBARS) and peroxide value (PV) in ferric-catalyzed soybean oil emulsions. Thermization significantly improved antioxidative properties of WP with 5T, 10T, and 15T treatments showing better protective effects compared to 20T and 30T treatments. Based on these results, native (0T) and thermized (5T, 10T, and 15T) Edam and Cheddar WP coatings, with and without enzymatically hydrolyzed casein (CH), were used to reduce oxidative degradation and moisture loss of cubed beef steak and pork loin. Thermized treatments significantly reduced TBARS and PV in both types of meat, with CH containing treatments showing enhanced antioxidative properties. Protein oxidation as reflected by carbonyl formation and a decrease in sulfhydryls was also reduced by thermization. Treated and native WP coatings significantly reduced moisture loss of meat samples. Cubed beef steak treated with Cheddar WP coatings were evaluated for microbiological quality and basic sensory attributes. Although not statistically significant, 5T, 10T, and 10TCH treatments numerically showed potential for microbial reduction up to 4 days of storage. Sensory evaluation showed significant protection of key sensory attributes by treatments throughout the storage period when compared to controls with the 5 min thermization showing the best effect on lowering offlavor development based on sensory scores. The effect of pH and glucomannan (GM) on antioxidative properties of thermized (5T) Cheddar WP coatings applied to catfish fillets was also investigated. Coatings at pH 7.0, 7.5, and 8.0 (with GM) showed markedly greater protection against oxidative degradation compared to coatings without GM, as reflected by TBARS values and PV after 7 days of storage. Carbonyl formation and oxidation of sulfhydryl groups were also significantly reduced by coatings containing GM. Cheddar WP-based edible coatings (pH 7.0–8.0) with GM markedly reduced lipid oxidation and protein oxidation of fresh catfish fillets.
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Improvement of the quality and shelf life of traditionally produced sorghum juice by addition of ashes, dried powered leaves and stem obtained from combretum sppMathipa, Morongwa Mary January 2022 (has links)
Thesis (Ph.D.(Microbiology)) -- University of Limpopo, 2022 / Traditional sorghum juice is produced in many African countries for human
consumption. The juice is very rich in calories, B-group vitamins including thiamine,
folic acid, riboflavin, nicotinic acid, and essential amino acids such as lysine. Low
earning income women at village level produce sorghum juice for home consumption
and sale. The short shelf life (2 to 3 days) of sorghum juice is a major problem for both
the brewers and consumers of this drink. The aim of the study was to use 12
Combretum plants to improve the microbiological quality and shelf life of sorghum
juice.
Fresh stems and leaves of C. caffrum, C. vendae, C. erythrophyllum, C. elaegnoides,
C. apiculatum, C. imberbe, C. adenogdium, C. padoides, C. bracteosum, C. kraussii,
C. mkuzense and C. zeyherii were collected at Nelspruit, National Botanical Gardens,
Mpumalanga, South Africa. Voucher specimens and tree labels were used to verify
the identity of the plants. The stems and bark collected were cut into pieces and air dried for 30 days. When dried, the plant material was ground to a fine powder and
stored in paper bags at room temperature. The wood was burnt in an open fire; fuel
was not used to minimise contamination.
The qualitative phytochemical composition of both the leaves and stems of
Combretum plants analysed in this study revealed the presence of saponins, tannins,
terpenoids, steroids, cardiac glycosides and flavonoids. The following
phytoconstituents were lost in the ashes; tannins with the exception of C. mkuzense
and C. padoides; cardiac glycosides and flavonoids. The quantitative phytochemical
analyses revealed that both the leaves, stems and some ashes such as C. apiculatum
and C. vendae contained appreciable levels of phenolic compounds, tannins and
flavonoids.
Quantitative analysis of antioxidant activity, the 2, 2, diphenyl-1-picrylhydrazyl (DPPH)
assay was used as a screen test for the radical scavenging ability of the compounds
present in the different 36 70% acetone extracts. DPPH screening method indicated
great scavenging activity with the 70% acetone leaf extracts of C. kraussii, C. zeyherii
and C. mkuzense. The leaf and stem extracts showed substantial great antioxidant
activity in a concentration-dependent manner. There was a significant decrease in the
antioxidant activity in the ashes (p=001), when compared to both the leaves and the
stems.
The proximate and nutritional analysis of the 70% acetone extracts were performed
by AOAC and ICPE protocols, respectively. The results indicated that all the extracts
had substantial amounts of ash, moisture, protein and energy. Mineral content of the
plant parts was analysed as well, calcium had the highest concentration, while zinc
was lowest in concentration. The mineral content decreased significantly in the stems
(p ≤ 0.05) when compared to the leaves. There was a further decrease in mineral
content with regard to the ashes with the exception of calcium. Based on these
findings, the leaves and ashes of C. adenogonium and C. apiculatum could provide a
good source of calcium in the diet, while C. adenogonium, C. bracteosum and C.
apiculatum had high levels of sodium.
A serial micro-dilution assay was used to determine the minimum inhibitory
concentration (MIC) values for 70% plant extracts using tetrazolium violet reduction as
an indicator of growth. Two Gram-positive (Stapylococcus aureus ATCC 29213 and
Enterobacter faecalis ATCC 29212) and two Gram-negative (Escherichia coli ATCC
25922 and Pseudomonas aeruginosa ATCC 27853) bacterial strains were used in this
study. The leaves had good antibacterial properties with the lowest MIC value being
0.04 mg/ml against E. coli and S. aureus. E. faecalis was found to be resistant against
all the leaves with the exception of C. imberbe. The stem extracts of Combretum spp.
tested in the study showed antimicrobial properties with the lowest MIC value being
0.04 mg/ml against E. coli shown by C. bracteosum. However, E. faecalis was
resistant against all the 12 plants tested. All the test microorganisms showed
resistance to the ashes, with the exception of S. aureus, which was found to be
susceptible to 75% of the test ash extracts with the lowest MIC value of 0.16 mg/ml.
Cytotoxicity and anticancer activity of the acetone extracts of the 12 Combretum plants
were evaluated using tetrazolium-based colorimetric assay (MTT assay) on A549 lung
carcinoma cells. The assays revealed that 50% of the leaf extracts of tested plants
showed cytotoxicity and cell proliferation inhibition in A549 lung carcinoma cells in a
concentration-dependent manner. The A549 cells were more sensitive to the following
plants: C. elaegnoides, C. erythrophyllum C. imberbe, C. kraussii and C. mkuzense.
The following stems extract, C. adenogdium and C. caffrum did not have any anticancer activity, whereas C. apiculatum and C. bracteosum were only able to
reduce cell viability to less than 60%. C. mkuzense, C. padoides, C. vendae and C.
zeyherii acted in a concentration-depended manner with the greatest activity seen at
the highest concentration (1000 µg/ml). The plants had activity at concentrations
between 31.25 and 1000 µg/ml allowing only 20% and 50%, respectively, of the cells
to remain viable. Ashes from C. mkuzense showed good anti-cancer activity at the
highest concentration (1000 µg/ml) reducing cell viability to around 10%.
Enterobacteriaceae, total coliform, S. aureus, B. cereus, E. coli and lactic acid bacteria
viability were studied during the four weeks storage period of prepared sorghum juices.
Juice samples were collected after preparation; the samples were serially diluted using
peptone water. Tempo instrument (Biomereiux) was used to enumerate total coliform,
total aerobic count, E. coli, S. aureus, lactic acid bacteria, enteric bacteria, yeast and
mould using the most probable number following the manufacturers instruction. C.
mkuzense and C. padoides plants were able to inhibit the growth of B. cereus, lactic
acid bacteria and S. aureus during the first three weeks of storage. E. coli was not
present throughout the four weeks storage time. Vitek 2 Compact (Biomereiux) was
used for the characterisation and identification of the dominant bacterial isolates using
biochemical reactions. The isolates were characterised by morphological differences.
Sixty five percent of the isolates were the Enterobacter genus that are commonly found
in soil, water, and sewage.
The nutritional composition and sensory properties of the prepared sorghum juices
treated with Combretum plants were investigated. All the juices had appreciable
amounts of protein, ash and energy. Sorghum juice treated with ashes of C. caffrum,
C. erythrophyllum and C. kraussii had the highest levels of proteins when compared
with other treated sorghum juices. The sorghum juices prepared in the study had
varying levels of trace element or minerals with potassium -(3, 55 – 104 mg/l) and
calcium (3.2-148 mg/l). Similarly, cobalt (-1.22), coppr (-0.99), iron(-0.962),
magnesium (0.004), sodium (-0.145), nickel (-2.7)) and zinc (-1.2)are present in very
low amounts. The juices treated with ashes had relatively higher levels of calcium,
potassium, magnesium and sodium. Sorghum juices treated with the ashes had better
sensory and organoleptic properties when compared with those treated with the
leaves. The juices treated with the ashes of C. caffrum and C. bracteseum were more
accepted by most of the panellist when compared with other treated juices.
Overall, this study presents valuable information on the phytochemical composition,
nutritional composition and antioxidant properties of some Combretum species in
South Africa. It recommended its use as food and in pharmaceutical preparations for
the local industries. In addition, Combretum plants showing the effects tested in this
study may be explored further for development into drugs. functional food as food
preservatives and nutraceutical applications, beside their traditional use / University of Limpopo and
Foodbev SETA
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Taxonomic Studies of Asian Horned Frog Genus Megophrys Kuhl and van Hasselt 1822 from Sunda Shelf / スンダシェルフ産コノハガエル属Megophrys Kuhl and van Hasselt 1822の分類学的研究MUNIR, Misbahul 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(地球環境学) / 甲第24064号 / 地環博第227号 / 新制||地環||43(附属図書館) / 京都大学大学院地球環境学舎地球環境学専攻 / (主査)准教授 西川 完途, 教授 瀬戸口 浩彰, 教授 本川 雅治 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DGAM
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Sequence Stratigraphy of the Lower Pennsylvanian (Bashkirian, Morrowan) Round Valley Limestone, Split Mountain Anticline (Dinosaur National Monument) and in the Eastern Uinta Mountains, UtahDavis, Nathan Robert 16 December 2010 (has links) (PDF)
The Early Pennsylvanian (Bashkirian/Morrowan) Round Valley Limestone of northeastern Utah was deposited on the Wyoming shelf, a slowly subsiding depositional surface located between the Eagle and Oquirrh basins. The 311-foot-thick Round Valley Limestone displays a distinct cyclicity formed by stacked, meter-scale parasequences, comprised of a limited suite of open- to restricted-marine limestones with minor interbeds of siltstone and shale. Open-marine deposits are characterized by mudstone and heterozoan wackestone-packstone microfacies (MF1-4) and comprise the lower portions of parasequences. Rocks of these microfacies were deposited during maximum high-order transgression of the shelf. As sediment filled the limited accommodation, the shelf became restricted, leading to deposition of mollusk-peloid dominated wackestone microfacies (MF6). Grainstones (MF5) microfacies are volumetrically limited in the Round Valley and represent deposition on isolated sand shoals that populated the shallow shelf. The complete Round Valley section at Split Mountain in Dinosaur National Monument is comprised of 5 intermediate-order sequences and 48 higher-order parasquences. Twenty-one of the shallowing-upward cycles are bounded by exposure surfaces as indicated by the occurrence of rhizoliths, glaebules, autobreccia and alveolar structures. Four of these that also indicate a significant drop in sea level (abnormal subaerial exposure surfaces and surfaces with erosional relief) constitute candidate sequence boundaries. The high percentage of cycles capped by exposure surfaces indicates that deposition of the Round Valley took place intermittently and that the Wyoming shelf was exposed during a significant portion of the Bashkirian epoch. Intermittency of deposition is confirmed by comparing the thickness and sequence architecture of the Round Valley Limestone with coeval strata in the eastern Oquirrh basin (Bridal Veil Limestone). The Bridal Veil Limestone is four times thicker and contains 24 cycles not represented on the Wyoming shelf.
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Accelerated Shelf Life Determination of Antioxidant Stabilized High Oleic Sunflower and Canola Oils in Plastic BottlesShearer, Christine Nicole 11 November 2010 (has links) (PDF)
Vegetable oil is an important commodity; however, the majority of commercially available vegetable oils have a fairly short shelf life, which limits their usefulness for long term food storage, disaster relief, space travel, food aid programs, and military rations. Vegetable oils with high oleic acid and reduced linolenic acid contents, especially with added antioxidant combinations, were previously found to have significantly longer oil stability index (OSI) values than traditional vegetable oils. This study used accelerated shelf life testing to estimate the ambient shelf life of high oleic sunflower oil (HOSUN) and high oleic canola oil (HOCAN), each containing 1,000 ppm ascorbyl palmitate, 200 ppm tertiary butyl hydroquinone, and 200 ppm mixed tocopherols. Oils were stored in the dark in low density polyethylene (LDPE), or polyethylene terephthalate (PET) bottles at 30, 40, 50, and 60°C. Control samples were stored in the dark in glass bottles at -50°C. Testing included peroxide values, qualitative headspace volatile analysis, descriptive sensory analysis, and consumer sensory acceptance. The estimated shelf life was calculated from the change in overall acceptance score over time using the Q10 method. The stabilized HOCAN in PET bottles was estimated to have a shelf life at ambient temperature of 6.8 years, while oil stored in LDPE bottles had an estimated shelf life of only 2.7 years. The estimated shelf life of HOSUN at room temperature in PET is 2.6 years and in LDPE is 0.88 years.
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[en] HIGH RESOLUTION RECONSTRUCTION OF PALEOENVIRONMENTAL VARIATIONS OVER THE LAST 14 KYEARS IN SEDIMENTS OF RIO DE JANEIRO CONTINENTAL SHELF, SE - BRAZIL / [pt] RECONSTRUÇÃO EM ALTA RESOLUÇÃO DAS VARIAÇÕES PALEOAMBIENTAIS EM SEDIMENTOS AO LONGO DOS ÚLTIMOS 14 MIL ANOS NA PLATAFORMA CONTINENTAL DO RIO DE JANEIRO, SE - BRASILLETICIA LAZZARI 20 July 2020 (has links)
[pt] Estudos paleoambientais sobre reconstruções climáticas no pretérito ajudam a compreender os processos biogeoquímicos atuais e, portanto, fornecem subsídios ao atual cenário de mudanças globais. As principais ferramentas utilizadas nesses estudos envolvem indicadores que requerem a integração de informações geoquímicas, geomorfológicas, oceanográficas e biológicas. No presente trabalho, dois testemunhos (RJ13-01 e RJ13-02) foram coletados na plataforma continental do Rio de Janeiro na isóbata de 100-m e datados através dos métodos de 210Pb e 14C, englobando, respectivamente, 14,5 cal kyr BP e 5,3 cal kyr BP. O objetivo principal do trabalho foi investigar o efeito de variáveis climáticas e ambientais sobre o aporte de material autóctono e alóctono na plataforma continental do Rio de Janeiro. Foram considerados dados geofísicos, granulometria, elementos traços (V, Cr, Mn, Ni, Cu, Zn, As, Sr, Ag, Cd, Sn, Ba, Tl, Pb e U), elementos majoritários (Ca, Si, Al e Fe), nitrogênio total (TN), carbono orgânico total (TOC), carbonato de cálcio (CaCO3), hidrocarbonetos alifáticos (n-alcanos) e hidrocarbonetos aromáticos (HPAs), assim como
consideradas razões entre elementos e compostos que indicam a introdução de material continental e biogênico, razões redox e de produtividade, além de marcadores de tipo de vegetação e de combustão. Os resultados ressaltaram três fases deposicionais na área estudada: a primeira fase vai de 14,5 cal kyr BP à 7,5 cal kyr BP, e se caracteriza pela ocorrência de granulometria média a grosseira, fragmentos de conchas, alto teor de Si (27 porcento), alto aporte de material biogênico Ca/Al (3,00), altos valores (30,5) de ACL (tamanho médio da cadeia n-alcanos) e alta contribuição de HPAs pirogênicos (33 porcento), por volta de 8,0 cal kyr BP, indicando maior incidência de clima seco na maioria dos períodos, além de ser marcada por níveis do mar mais baixos. A segunda fase, entre 7,5 cal kyr BP e 4,5 cal kyr BP, mostrou influência das Águas Centrais do Atlântico Sul (SACW), marcada por um máximo de elevação do nível do mar, eventos de seca com maior intensidade de incêndios naturais com alta contribuição de HPAs pirogênicos de 5-6 anéis (68 porcento), entre 6,1 cal kyr BP e 4,1 cal kyr BP, e alto aporte de material continental Al/Ca (0,69); Fe/Ca (0,27) e alta produtividade. A terceira fase cobre o Holoceno superior, a partir de 4,5 cal kyr BP até o presente. Nessa fase, foram encontrados fluxos mais elevados de matéria orgânica, entre 3,2 cal kyr BP a 3,3 cal kyr BP (RJ13-01) e 3,4 cal kyr BP (RJ13-02), como indicado por TN, TOC, Ni, Cu, Zn, HA e HPAs, e um maior aporte continental, devido aos altos valores de razões redox-sensíveis a partir de 2,5 cal kyr BP no RJ13-01 e ao longo do testemunho RJ13-02. Esses fatores provavelmente são decorrentes do
deslocamento da Zona de Convergência Intertropical (ITCZ) mais ao sul, deixando o clima mais úmido na Amazônia, a intensificação do SAMS trazendo umidade para SE do país através da SACZ. Porém, também podem refletir um evento de menor nível do mar, que influenciou nos níveis de oxigênio na coluna d água. Por outro lado, indicadores de clima seco (ACL, HPAs pirogênicos de 5-6 anéis) sugerem que houve oscilações entre clima úmido e seco ao longo do Holoceno superior. Desta forma, os indicadores orgânicos e inorgânicos considerados nos testemunhos da plataforma continental do RJ possibilitaram avaliar e corroborar dados de outros estudos sobre os eventos climáticos ocorridos nos últimos 14 mil anos no SE do Brasil, e suas relações com fatores como: variações no nível do mar, mudanças na ITCZ, intensificação da SAMS influenciando a SACZ, mudanças nos padrões de ventos e na Corrente do Brasil; influência da SACW mais no sentido S-W do sistema de ressurgência de Cabo Frio; variações climáticas com registros de incêndios naturais e variações da vegetação; além de registros que podem ser relacionados à ocupação humana. / [en] Paleoenvironmental studies on climate reconstructions in the past help to understand the current biogeochemical processes and therefore become increasingly important in the current scenario of global changes. The main parameters used in these studies involve proxies that require the integration of geochemical, geomorphological, oceanographic and biological information. In this study two cores (RJ13-01 and RJ13-02) were collected on the continental shelf of Rio de Janeiro in the isobath 100-m and dated by 210Pb and 14C methods covering14.5 cal kyr BP and 5.3 cal kyr BP, respectively. The main goal of this work was to investigate the effect of climatic and environmental variables on the autochthonous and allochthonous material inputs in the continental shelf of Rio de Janeiro. For this, geophysical properties, grain size, trace elements (V, Cr, Mn, Ni, Cu, Zn, As, Sr, Ag, Cd, Sn, Ba, Tl, Pb and U), major elements (Ca, Si, Al and Fe), total nitrogen (TN), total organic carbon (TOC), calcium carbonate (CaCO3), aliphatic hydrocarbons (n-alkanes) and polycyclic aromatic hydrocarbons (PAHs) were considered jointly with continental and biogenic input proxies, redoxsensitive and productivity proxies besides vegetation type and combustion proxies. Results highlighted three periods: the first period (from 14.5 to 7.5 cal kyr BP) with the occurrence of mean grain size of the sediment, shell fragments, high content of Si (27 percent), high input of biogenic material Ca/Al (3.00) and high ACL (average chain length) values (30.5). In addition to high contribution of pyrogenic PAHs (33 percent) around 8.0 cal kyr BP indicating higher incidence of dry weather in most periods; marked by a low sea level. The second period between 7.5 cal kyr BP and 4.5 cal kyr BP showed the influence of the South Atlantic Central Waters (SACW) marked by a maximum transgression of the sea, drought events with greater intensity of wildfires with high contribution of pyrogenic PAHs of 5-6 rings (68 percent) between 6.1 and 4.1 cal BP kyr BP and high input continental materials Al/Ca (0.69); Fe/Ca (0.27) and high productivity. The third period covers the late Holocene from 4.5 cal kyr BP to present. In this period, higher fluxes of organic matter were found between 3.2 cal kyr BP to 3.3 cal kyr BP (RJ13-01) and 3.4 cal kyr BP (RJ13-02), as indicated by TN, TOC, Ni, Cu,Zn, n-alkanes and PAHs, and higher continental input due to high redox-sensitive proxies from 2.5 cal kyr BP in RJ13-01 and along RJ13-02. These factors are probably related to the displacement further south of the Intertropical Convergence Zone (ITCZ), which brought humidity to Amazon, the intensification of SAMS bringing humidity to SE of Brazil trought SACZ. Also has been marked by the decrease in sea level which influenced the oxygen levels in the water column. On the other hand, dry climate indicators (ACL, pyrogenic PAHs with high molecular weight) suggest that there were fluctuations between wet and dry climate along the late Holocene. Thus, the organic and inorganic proxies considered on the cores of continental shelf of Rio de Janeiro allowed to evaluate and corroborate the data of other studies of climate events over the past 14,000 years in SE Brazil and their relation to the facts such is the variations in the sea-level, chances in ITCZ, the intensification of SAMS and SACZ, changes in wind pattern, and in the Brazilian current; influence of the SACW further S-W of the Cabo Frio upwelling system; and climate variations with records of wildfires and variation on the vegetation; in addition to records that could be
related to human occupation.
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Topographic Effects on Internal Waves at Barkley CanyonAnstey, Kurtis 31 August 2022 (has links)
Submarine canyons incising the continental shelf and slope are hot spots for topography-internal wave interactions, with elevated dissipation and mixing contributing to regional transport and biological productivity. At two Barkley Canyon sites (the continental slope below the shelf-break, and deep within the canyon), four overlapping years of horizontal velocity time-series data are used to examine the effects of irregular topography on the internal wave field. Mean currents are topographically guided at both sites, and in the canyon there is an inter-annually consistent, periodic (about a week) up-canyon flow (-700 to -900 m) above a near-bottom down-canyon layer. There is elevation of internal wave energy near topography, up to a factor of 10, 130 m above the slope, and up to a factor of 100, 230 m above the canyon bottom. All bands display weak inter-annual variability, but significant seasonality. Sub-diurnal and diurnal flows are presumably sub-inertially trapped along topography, and the diurnal band appears to be forced locally (barotropically). Both sites have high near-inertial energy. At the slope site, near-inertial energy is attenuated with depth, while in the canyon it is amplified near the bottom. Both sites show intermittent near-inertial forcing associated with wind events, downward propagation of high-mode internal waves, and the seasonal mixed-layer depth, though fewer events are observed in the canyon. Free semidiurnal internal tides are focused and reflected near critical shelf-break and canyon floor topography, and appear to experience both local and remote (baroclinic) forcing. The high-frequency internal wave continuum has enhanced energy near bottom at both sites (up to 7 times the open-ocean Garrett-Munk spectrum), and inferred dissipation rates increasing from a background of less than 10^-9 W kg^-1 and reaching 10^-7 W kg^-1 near topography. Dissipation is most strongly correlated with the semidiurnal (M2) constituent at both sites, with secondary contributions from the sub-diurnal (Sub_K1) band on the slope, and the near-inertial (NI) band in the canyon. Power laws for these dependencies are dissipation ~ M2^0.83 + Sub_K1^0.59 at the slope, and dissipation ~ M2^1.47 + NI^0.24 in the canyon. There is evidence in spectra of a near-buoyancy frequency build-up of energy correlated with high-frequency continuum variability, with a power law fit of 'shoulder' power ~ dissipation^0.34 that is independent of site topography. Though some general results are expected from observations at other slope and canyon sites, the greater temporal extent of these data provide a uniquely long-term evaluation of such processes. / Graduate
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Perishable Food Waste Reduction Through Technological Implementation at the Retail Level of the Food Supply ChainHarriman, Cassandra 01 June 2021 (has links) (PDF)
Food waste has become a disaster of global proportion that the world can no longer turn a blind eye to. This paper aims to reduce food waste at the retail level of the food supply chain by recommending and quantifying the effects of current technology that can be implemented in traditional supermarkets. This research recommends that retailers implement electronic shelf labels in stores and employ dynamic pricing of perishable products, leading to reduction of food waste. No prior research had considered the primary goal of reducing food waste while preserving retailer profit through technological implementation. This paper quantifies the effects of implementing this technology and provides economic justification of the required investment through the calculation of profitability metrics and discussion of environmental regulations retailers will soon have to abide by. Our results indicate, even in the most conservative of scenarios, that the payback period for full implementation of electronic shelf labels will be less than or slightly over one year and the return on investment is high in all situations discussed. Sensitivity analyses of labor costs, revenue, and profitability ratios are illustrated to provide a full breadth of these results.
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The role of microbes and organic matter in the genesis of complex carbonate facies and lithologies referred to as leopard rock, Sacramento Mountains, New MexicoTischler, Keith Louris 30 April 2021 (has links)
The colloquially named leopard rock of the Holder and Laborcita formations (Late Pennsylvanian-Early Permian) is an algal/foraminiferal boundstone that occurs within a cyclic, interfingered, carbonate siliciclastic system in the Sacramento Mountains of southeastern New Mexico) and often accompanies phylloid algal mounds. This project is the first to fully characterize and evaluate the evidence that leopard rock is microbial in origin and assess the potential influence of methane seeps and deltaic organics on its genesis. Characterization of the algal-foraminiferal boundstone revealed a highly variable expression in outcrop based on geolocated photo imagery, hand samples, optical microscopy, and scanning electron microscopy (SEM) data. Leopard rock is interpreted as microbial in origin based upon all features observed in aggregate, particularly upward-oriented concentric gradational laminae and striking clusters of segmented curvilinear cylinders (~1000 nm long). Leopard rock is best described as thrombolytic. A comprehensive categorization into thrombolite types was conducted and field and analytical data were used in creating a geospatial data base. The data was evaluated spatially in ArcMap for co-occurrence, trends, and possible associations within, and between, categorizations and formations. Distribution and associations of dome (1-3 m), small coniform (< 1 m), and planar outcrop structures and thrombolite types reflect a hierarchy of complexity and prevalence that would be expected from a microbial system. An extensive multi-scale feature comparison of potential modern analogues from Australia, the Bahamas, and Canada, in conjunction with contiguous paleo-analogues, support the interpretation of a highly adaptable complex microbial ecosystem. Results were also consistent within the global chemical, biologic, and physical context at the time of deposition. Evidence for methane seep contribution support the plausibility of supplemental microbial energy sources based on modern examples and limited paleo-analogues. Stratigraphic position and a paucity of data do not support a significant role for deltaic bathymetry or organic influx in leopard rock genesis. The results of this study provide robust evidence that leopard rock is a multi-faceted complex microbial thrombolite that displays a continuum of expression not represented by one all-encompassing term and illustrates the value of multi-parameter analyses augmented across time and space using analogues and geospatial software.
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