Master of Science / Department of Food Science / Elizabeth A. E. Boyle / To validate how packaging and storage reduces Listeria monocytogenes (Lm) on whole muscle turkey jerky and smoked sausage sticks, four packaging systems, including heat seal (HS), heat seal with oxygen scavenger (HSOS), nitrogen flushed with oxygen scavenger (NFOS), and vacuum (VAC), and four ambient temperature storage times were evaluated. Commercially available whole turkey jerky and pork and beef smoked sausage sticks were inoculated with Lm using a dipping or hand-massaging method, respectively. There was no interaction on packaging and storage time on Lm reduction on smoked sausage sticks and an Lm log reduction of >2.0 log CFU/cm[superscript]2 was achieved in smoked sausage sticks packaged in HS, HSOS, and VAC. A >2.0 log CFU/cm[superscript]2 reduction was achieved after 24 h of ambient temperature storage, regardless of package type. NFOS was less effective in reducing Lm by more than 0.5 log CFU/cm[superscript]2 compared to HS, HSOS or VAC. After 30 d of ambient storage, Lm had been reduced by 3.3 log CFU/cm[superscript]2 for all packaging environments. In turkey jerky, Lm reduction was affected by the interaction of packaging and storage time. HS, HSOS, NFOS, or VAC in combination with 24, 48, or 72 h ambient temperature storage achieved <1.0 log CFU/cm[superscript]2. After 30 d at ambient temperature storage, Lm was reduced by >2.0 log CFU/cm[superscript]2 in HS and VAC, and could serve as a post-lethality treatment. Alternatively, processors could package turkey jerky in HSOS or NFOS in combination with 30 d ambient storage period as an antimicrobial process. Very little data has been published describing how packaging atmospheres affects Lm survival in RTE meat. The mechanism for Lm reduction under these conditions is not fully understood and additional research is needed.

Master of Science / Food Science Institute / Kelly J. K. Getty / The United States Department of Agriculture’s Food Safety and Inspection Service require that processors of ready-to-eat (RTE) meat and poultry products implement post- processing intervention strategies for controlling Listeria monocytogenes. The objective of our study was to determine the effect of packaging methods and storage time on reducing L. monocytogenes in shelf-stable meat snacks. Commercially available kippered beef steak strips (14 × 2.5 cm rectangle piece) and turkey tenders (4 × 4 cm square piece) were dipped into a five-strain L. monocytogenes cocktail, and dried at 23°C until a water activity of approximately 0.80 was achieved. Inoculated samples were packaged with four treatments: 1) vacuum, 2) nitrogen flushed with oxygen scavenger, 3) heat sealed with oxygen scavenger, and 4) heat sealed without oxygen scavenger. Samples were stored at 23°C and evaluated for L. monocytogenes levels at 0, 24, 48, and 72 h. Initial levels (time 0) of L. monocytogenes were approximately 5.7 log CFU/cm[superscript]2 for steak and tenders. For kippered beef steak, there was no interaction among packaging treatments and storage times (P > 0.05) whereas, storage time was different (P <0.05). A 1 log reduction of L. monocytogenes was observed at 24 and 48 h at 23°C for all packaging treatments and a 2.1 log CFU/cm[superscript]2 reduction occurred at 72 h. A 1 log CFU/cm[superscript]2 reduction of L. monocytogenes was observed after 24 h of storage for turkey tenders for all packaging treatments. After 48 h of storage time turkey tenders showed >1 log CFU/cm [superscript]2 reduction of L. monocytogenes for all packaging treatments except for vacuum packaged where only 0.9 log CFU/cm[superscript]2 reduction was observed. Log reductions at 72 h for all packaging treatments for turkey tenders ranged from 1.5 to 2.2. Processors of kippered beef steak and turkey tenders could use vacuum, nitrogen-flushing, or heat sealed with an oxygen scavenger packaging methods and hold product 24 h prior to shipping to reduce potential L. monocytogenes numbers by ≥1 log. However, processors should be encouraged to hold packaged product a minimum of 72 h to enhance the margin of safety for L. monocytogenes control.

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Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-06-30T12:55:21Z No. of bitstreams: 1 EDNEIDE RODRIGUES LOPES DA SILVA - DISSERTAÇÃO PPGEA 2011..pdf: 9416764 bytes, checksum: a8180090346a0ff5cc4d09e54de31266 (MD5) / Made available in DSpace on 2018-06-30T12:55:21Z (GMT). No. of bitstreams: 1 EDNEIDE RODRIGUES LOPES DA SILVA - DISSERTAÇÃO PPGEA 2011..pdf: 9416764 bytes, checksum: a8180090346a0ff5cc4d09e54de31266 (MD5) Previous issue date: 2011-09 / A mandioca (Manihot esculenta Crantz) é cultivada em todos os estados brasileiros devido à sua fácil adaptação. A mandioca de mesa está cada vez menos frequente na forma "in natura", nas grandes cidades e supermercados, em virtude da rápida deterioração pós-colheita. Atualmente, observa-se uma diversificação de produtos ofertados, como a mandioca minimamente processada, pré-cozida congelada, cozida embalada a vácuo, "chips", entre outros. Procurou-se, com base neste contexto, investigar, através deste trabalho, a elaboração de "palitos" de mandioca submetidos a desidratação osmótica em solução de sacarose (30%) mais cloreto de sódio (3%) condimentado com bacon, charque e ervas finas, nas temperaturas de 45, 50 e 55°C, durante 40 minutos; a determinação da cinética de desidratação osmótica, segundo as equações de Cavalcanti Mata, Page e Logaritmo; a textura dos palitos de mandioca desidratados e fritos e a avaliação do aspecto sensorial dos palitos de mandioca fritos. A cinética de desidratação de palitos de mandioca em solução osmótica, sofre forte influência da temperatura da solução culminando com a diminuição da transferência de massa com o aumento da temperatura. As três equações propostas se ajustaram satisfatoriamente aos dados experimentais de desidratação osmótica de palitos de mandioca, nas temperaturas de 45, 50 e 55 °C, com coeficientes de determinação maiores que 99%; Os testes de textura indicaram que a maior resistência ao corte foi oferecida pela amostra in natura e que a desidratação osmótica contribuiu para a redução da resistência, em todos os tratamentos. Constatou-se, ainda, que o uso de diferentes condimentos não causou diferença significativa entre os tratamentos após a desidratação osmótica. Todos os produtos elaborados nesta pesquisa (palitos de mandioca desidratados osmoticamente em solução de sacarose (30%) e cloreto de sódio (3%), condimentados, respectivamente, com bacon, charque e ervas finas) foram bem aceitos pelos avaliadores, sendo o produto charque o que teve a maior preferência em todas as propriedades sensoriais. / Cassava (Manihot esculenta Crantz) is cultivated in ali Brazilian states, because of its easy adaptation. However, sweet cassava is less and less frequent, natura" form, in large cities and supermarkets, due to its fast postharvest deterioration. It is observed, today, a diversification of offered products, such as minimally processed, pre-cooked, frozen, packaged cooked in vácuo, "chips" cassava, etc. Before mis context, this work aimed to investigate the elaboration of cassava "sticks", subjected to osmotic dehydration in solution of saccharose (30%) plus sodium chloride (3%) spiced with bacon, beef jerky and herbs, with temperatures of 45, 50 and 55°C for 40 minutes; the determination of kinetics of osmotic dehydration according to Cavalcanti Mata's equations, Page and Logarithms; the cassava sticks texture dehydrated and fried; and the evaluation of the sensorial aspect of the fried cassava sticks. Cassava sticks dehydration kinetics, in osmotic solution, suffers a strong influence of the solution temperature, culminating in the decrease of mass transfer with the increase of temperature. The three proposed equations were adjusted satisfactorily to the experimental data of cassava sticks osmotic dehydration in temperatures of 45, 50 and 55 °C, with coefficients of determination higher than 99%. The texture tests pointed out that the greater resistance to the cut was offered by the sample in natura, and that the osmotic dehydration contributed for reducing the resistance in ali the treatments. It was also found that the use of different spice did not cause considerable difference between the treatments after the osmotic dehydration. Ali the products elaborated in this research (cassava sticks dehydrated osmotically in saccharose solution (30%) and sodium chloride (3%), spiced, respectively, with bacon, beef jerky and herbs) were well accepted by the evaluators, being the beef jerky the one that had the greater preference in ali sensorial proprieties.

Background: Olfactory dysfunction is a common symptom of many neurodegenerative diseases, and age-related macular degeneration (AMD) is a late-onset neurodegenerative disease. Objective: Thus, the aim of this study was to investigate olfactory functions in patients with AMD. Methods: A total of 69 subjects with AMD and 69 age- and sex-matched healthy controls were enrolled. After a complete ophthalmic evaluation, the AMD patients were subclassified as earlyand late-stage AMD. Psychophysical testing of olfactory function was performed using the validated Sniffin’ Sticks test. Results: This study was carried out in 138 subjects, with a mean age of 74.3 ± 8.9 years (range 51–89). The current investigation showed the following two major findings: (1) patients with AMD had decreased olfactory abilities, especially in odor discrimination and odor identification, even at early stages compared to controls, whereas patients had decreased olfactory abilities in all subtasks of olfactory testings in advanced stages of AMD disease, and (2) as the visual acuity of AMD patients decreased, the olfactory abilities of these patients worsened. Conclusion: This study demonstrated that AMD had significant negative effects on all orthonasal olfactory tasks, particularly in advanced stages. Similar to other neurodegenerative diseases, odor discrimination and identification seemed to be more affected than odor detection threshold tasks.

Multiple scholars have briefly discussed the Maya use of the atlatl. Yet, there has never been a decisive encompassing discussion of prevalence and use of the atlatl in the Maya region with multiple lines of support from iconographic and artifactual analyses. This thesis explores the atlatl at Chichén Itzá, Tikal, and Caracol Maya sites to prove that atlatl prevalence can be interpreted primarily based on projectile point “classification function” analysis with support from iconographic and artifactual remains. The classification functions are derived from creating mutually exclusive groups of dart points and arrow points by using discrete functional analysis. Discerning between dart and arrow points can be completed with a high degree of accuracy based on maximum shoulder width of lithic points in an assemblage. Because the atlatl and bow complexes have been primarily constructed of perishable materials, the best method to determine the prevalence of atlatl use is by identifying the launcher based on projectile point identification. Using a cross-site comparison of projectile point size, the Maya use and prevalence of the atlatl will be elucidated

A new product, pork sticks, was developed. Optimum shelf life and safety were major concerns associated with this product. Potassium lactate (3%) or citric acid (0.5%, 0.56%, 0.60% or 0.66%) was added to pork sticks to determine their effects on microbial growth, sensory evaluation, and shelf life when stored frozen (-20°C), refrigerated (2°C), or at room temperature (22°C). Two raw materials, pork blade meat (shoulder meat; 91% lean, 9% fat) and regular 80:20 pork trim (80% lean, 20% fat) were used. The consumer panel preferred lean pork sticks made from blade meat over high-fat pork sticks made from regular 80:20 pork trim, regardless of the addition of potassium lactate (3%) or citric acid (0.5%). Pork sticks vacuum-packaged and held at 2°C or -20°C did not develop bacterial spoilage during six months storage. However, bacterial spoilage and oxidative rancidity occurred in the unpackaged control samples held at 22°C for one month. Incorporation of potassium lactate (3%) or citric acid (0.5%) decreased the color uniformity and red color intensity and increased the brown color intensity of the pork sticks made from blade meat. Vacuum-packaged pork sticks with added citric acid (0.56%, 0.60% and 0.66%) stored at 22°C did not develop bacterial spoilage, but discoloration occurred after one month storage.

This research is an investigation of the Late Holocene technological transition from the spearthrower and dart to the bow and arrow in north central Texas. It is conducted through a theoretical approach that utilizes ethnographic research, experimental archaeology and the archaeological record to elucidate differences in the behaviors and hunting strategies of Late Archaic and Late Prehistoric groups. It first confirms that there was a transition. Second, a lithic analysis demonstrates that there are fundamental differences in the sizes of the stone dart and arrow points that relate to the propulsive requirements of the weapon systems. Third, it is shown these size differences constrain maintenance potentials and that indeed dart and arrow points exhibit stark differences in their life histories in spite of being employed for the same task. And finally, the faunal record suggests that this transition was associated with an increase in foraging efficiency.

The Swedish school has the task of allowing all pupils to develop their ability to verbally communicate in the classroom. Through communicating verbally, the pupils will gain confidence in their linguistic ability in the social-science subjects. The purpose of this study is to investigate how a random selection with “ice cream sticks” can help to create a dialogic classroom, and how the participants perceive this type of teaching method, and if there is possible change in communicating verbally. The questions the study will answer are:  ·       How do the teacher's questions and responses to the student responses affect student participation? ·       To what extent does mutual respect arise from classroom dialogue? ·       How do pupils and class teachers experience the random selection at the beginning and end of a period of three weeks? ·       To what extent and in what way has the changed way of teaching contributed to a dialogical classroom in the social-science subjects?   This survey includes pupils and teachers from two classes in grade four and five. The qualitative methods used in this survey are observations and interviews. The material has been analyzed using theories about how dialogue is created in the classroom and how the teaching form with “ice cream sticks” can be organized. The result that emerged from this research is that with the help of the teaching style and the teachers' approaches, which is how they ask questions and how they respond to the students, the quantitative student participation has contributed to an increased classroom dialogue.

Until recent years, terahertz (THz) waves were an undiscovered, or most importantly, an unexploited area of electromagnetic spectrum. This was due to difficulties in generation and detection of THz waves. Recent advances in hardware technology have started to open up the field to new applications such as THz imaging. This non-destructive and non-contact imaging technique can penetrate through diverse materials such that internal structures, in some cases invisible to other imaging modalities, can be visualized. Today, there are variety of techniques available to generate and detect THz waves in both pulsed and continuous fashion in two different geometries; transition, and reflection modes. In this thesis continuous wave THz imaging was employed for higher spatial resolution. However, with any new technology comes its challenges; automated processing of THz images can be quite cumbersome. Low contrast and the presence of a widely unknown type of noise make the analysis of these images difficult. In this work, there is an attempt to detect defects in composite material via segmentation by using a Terahertz imaging system. According to our knowledge, this is the first time that this type of materials are being tested under Terahertz cameras to detect manufacturing defects in aerospace industry. In addition, segmentation accuracy of THz images have been investigated by using a phantom. Beyond the defect detection for composite materials, this can establish some general knowledge about Terahertz imaging, its capabilities and limitations. To be able to segment the THz images successfully, pre-processing techniques are inevitable. In this thesis, a variety of different image processing techniques, self-developed or available from literature, have been employed for image enhancement. These methods range from filtering to contrast adjustment to fusion of phase and amplitude images by using fuzzy set theory, to just name a few. The result of pre-procssing and segmentation methods demonstrates promising outcome for future work in this field.