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A Biopsychosocial Model of Dietary Restraint in Early Adolescent BoysMitchell, Sara H. 08 1900 (has links)
The current study replicated and extended previous research by examining empirically the direct and indirect influence of social pressure (to lose weight and diet), social body comparisons, internalization of the thin ideal, body dissatisfaction, self-esteem, and cardiorespiratory fitness on self-reported dietary restraint in a diverse sample of middle school boys (n = 663); Mage was 12.49 years (SD = .99). With IRB approval, parental consent, and child assent, during annual FITNESSGRAM testing, participants completed questionnaires that measured the study’s constructs. Cardiorespiratory fitness (CRF) was determined by the boys’ performance on the PACER running test. The proposed model was examined using structural equation modeling (SEM). Because measures demonstrated univariate and multivariate normality, the maximum likelihood procedure within EQS to examine the measurement and structural models was used. Fit was determined using a two-index procedure. Participants were randomly split into exploratory (Sample A - 331) and confirmatory (Sample B - 332) samples. For Sample A, the measurement and structural models fit the data well. The structural model was confirmed in Sample B, with the same paths being significant and nonsignficant. For both Sample A and Sample B, 35% of the Dietary Restraint variance was explained. These findings support a multifactorial approach to understanding boys’ self-reported dietary restraint, and illuminate the negative influence of sociocultural weight pressures and salutary effects of CRF on early adolescents’ psychosocial well-being and dietary behaviors.
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Crude oil-utilizing strain Desulfovibrio vulgaris D107G3, a mesophilic sulfate-reducing bacterium isolated from Bach Ho gas-oil field in Vung Tau, VietnamNguyen, Thi Thu Huyen, Tran, Thi Kim Thoa, Lai, Thuy Hien 29 December 2021 (has links)
Some of anaerobic, mesophilic sulfate-reducing bacteria that produce H₂S and cause microbial metal corrosion can degrade crude oil in anaerobic conditions. In this study, a mesophilic sulfate-reducing bacterial strain D107G3 isolated from Bach Ho gas-oil field in Vung Tau, Vietnam that is able to utilize crude oil in the anaerobic condition is reported. The strain D107G3 was classified as a Gram-negative bacterium by using Gram staining method. Basing on scanning microscopy observation, the cell of a strain D107G3 had a curved rod shape. The 16S rRNA gene sequence analysis showed that the strain D107G3 was identified as Desulfovibrio vulgaris with 99.7% identity. The suitable conditions for its growth that was determined via estimating its H₂S production was the modified Postgate B medium containing 1% (v/v) crude oil, 1% NaCl (w/v), pH 7 and 300C incubation. In these conditions, the strain D107G3 can consume 11.4 % of crude oil total and oxidize heavy crude oil (≥ C45) for one month at anoxic condition. These obtained results not only contribute to the science but also continue to warn about the dangers of mesophilic sulfate reducing bacteria to the process of crude oil exploitation, use, and storage in Vung Tau, Vietnam. / Trong bài báo này, chủng vi khuẩn khử sunphat (KSF) ưa ấm D107G3 phân lập từ giếng khoan dầu khí mỏ Bạch Hổ, Vũng Tàu, Việt Nam có khả năng sử dụng dầu thô trong điều kiện kị khí được công bố. Chủng D107G3 được xác định là vi khuẩn Gram âm nhờ phương pháp nhuộm Gram. Quan sát trên kính hiển vi điện tử quét cho thấy tế bào chủng D107G3 có hình que cong. Kết quả phân tích trình tự gen 16S rRNA đã xác định được chủng D107G3 thuộc loài Desulfovibrio vulgaris với độ tương đồng 99.7%. Thông qua đánh giá lượng H₂S tạo thành đã khám phá được điều kiện thích hợp cho sinh trưởng của chủng D107G3: môi trường Postgate B cải tiến chứa 1% (v/v) dầu thô, 1 % NaCl (gL⁻¹), pH 7 và nuôi cấy ở 30°C. Trong điều kiện đó, chủng D107G3 đã sử dụng được 11.4 % hàm lượng dầu tổng số, thành phần dầu bị phân huỷ là các n-parafin có mạch
C≥45 sau 1 tháng nuôi cấy kỵ khí. Các kết quả này đóng góp về mặt khoa học và tiếp tục cảnh báo mối nguy hại của KSF ưa ấm đến việc khai thác, sử dụng và bảo quản dầu mỏ ở Vũng Tàu, Việt Nam.
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Evaluating the Effect of Selected Soaking Pretreatments on the Color Quality and Phenolic Content of Purple Potato ChipsZhang, Kai January 2017 (has links)
No description available.
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[pt] DECOMPOSIÇÃO TÉRMICA DO SULFATO DE ZINCO NA PRESENÇA DE AGENTES MODIFICADORES DO MECANISMO REACIONAL / [en] ZINC SULFATE THERMAL DECOMPOSITION IN THE PRESENCE OF REACTION MECHANISM MODIFIERS AGENTSGABRIELA VICTORIA TOMASI KURBAN 14 September 2020 (has links)
[pt] O hidrogênio apresenta-se como um potencial combustível alternativo em substituição aos combustíveis fósseis e, por essa razão, estudos e pesquisas sobre as rotas de produção e armazenamento desse recurso estão em voga no meio científico. Os métodos para obtenção de H2 são diversos, no entanto, nem todos os métodos são provenientes de fontes renováveis. Os ciclos termoquímicos de quebra da molécula da água são alternativas promissoras para a geração de H2. Neste contexto, o ciclo do enxofre-iodo é um dos ciclos em destaque, caracterizando-se por um processo em três etapas cuja terceira etapa é a etapa desafiadora do ciclo, onde ocorre a decomposição do ácido sulfúrico que exige um gasto energético elevado. A utilização de sulfatos metálicos associados a agentes redutores e aditivos em substituição ao ácido sulfúrico no ciclo enxofre-iodo tem sido estudada. Deste modo, o presente trabalho de pesquisa avaliou a decomposição térmica do sulfato de zinco monohidratado na presença dos agentes modificadores enxofre elementar, Pd-(gama)Al2O3, CeO2 e CeO2/ZnO que estimulam a transformação do trióxido de enxofre no respectivo dióxido. Além de um estudo termodinâmico do sistema reacional e análises térmicas via TG que indicaram uma mudança no comportamento da decomposição do sulfato na presença do agente redutor e dos aditivos, o trabalho previu a caracterização dos produtos reacionais indicando a presença do óxido de zinco e um estudo cinético dos sistemas na presença dos agentes mencionados, permitindo o cálculo das energias de ativação e dos parâmetros cinéticos. A apreciação termodinâmica indicou um aspecto favorável quanto a diminuição da temperatura de decomposição do sulfato de zinco assim como no que diz respeito à transformação de SO3 em SO2. Na presença de Pd-(gama)Al2O3 a temperatura final da decomposição do sulfato ocorreu 100 graus Celsius abaixo da temperatura habitual. A perda de massa total calculada para a decomposição do sulfato puro foi de 55 por cento. Nos estudos com a presença dos agentes as perdas de massa total calculadas foram 60 por cento, 54 por cento, 62 por cento, 57 por cento correspondentes ao sulfato de zinco na presença do enxofre elementar, Pd-(gama)Al2O3, CeO2 e CeO2/ZnO, respectivamente. / [en] Hydrogen presents itself as a potential alternative fuel to replace fossil fuels and, for this reason, studies and research on the production and storage routes of this resource are in vogue in the scientific community. The methods for obtaining H2 are diverse, however, not all methods are from renewable sources. The thermochemical cycles of splitting water are promising alternatives. In this context, the sulfur-iodine cycle is one of the highlighted cycles, characterized by a three-stage process whose third stage is the challenging stage of the cycle, where the decomposition of sulfuric acid occurs, which requires a high energy expenditure for formation selection of sulfur dioxide and oxygen. The use of metal sulfates associated with reducing agents and additives in substitution for sulfuric acid in the sulfur-iodine cycle has been studied. Thus, the present research work evaluated the thermal decomposition of zinc sulfate monohydrate in the presence of elemental sulfur modifying agents, Pd-
(gamma)Al2O3, CeO2 and CeO2 / ZnO that stimulate the transformation of sulfur trioxide in the respective dioxide. In addition to a thermodynamic study of the reaction system and thermal analyzes via TGA that indicated a change in the sulphate decomposition behavior in the presence of the reducing agent and additives, the work predicted the characterization of the reaction products indicating the presence of zinc oxide and a study kinetics of the systems in the presence of the mentioned agents, allowing the calculation of activation energies and kinetic parameters. The thermodynamic assessment indicated a favorable aspect regarding the decrease in the decomposition temperature of zinc sulfate as well as with regard to the transformation of SO3 into SO2. In the presence of Pd-(gamma)Al2O3, the final temperature of the sulphate decomposition occurred 100 C degrees below the usual temperature. The total mass loss calculated for the decomposition of pure sulfate was 55 percent. In studies with the presence of agents, the calculated total mass losses were 60 percent, 54 percent, 62 percent, 57 percent corresponding to zinc sulfate in the presence of elemental sulfur, Pd-(gamma)Al2O3, CeO2 and CeO2 / ZnO, respectively.
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Vinn/vinn - eller svinn? En studie om hur livsmedel kan doneras till välgörenhet istället för att kasserasÅhnberg, Anna January 2011 (has links)
Ungefär en fjärdedel av den klimatpåverkan som de svenska hushållen orsakar kommer från maten vi äter, eller närmare bestämt från de utsläpp av växthusgaser som maten ger upphov till på sin väg från jord till bord. Om maten slängs innan den konsumeras har denna miljöpåverkan skett i onödan. Uppsatsen undersöker VIS (Välgörenhet Istället för Svinn), en svinnåtgärd där fullvärdiga livsmedel istället för att slängas, skänks till välgörenhet. Målet är att undersöka hur VIS fungerar, samt att bidra till ökade kunskaper om detta för Sverige nya sätt att bemöta svinnproblematiken. VIS styrkor och svagheter, liksom de hot och möjligheter som kan finnas, har undersökts med hjälp av en SWOT-analys. Uppsatsen utgår ifrån företaget Allwin i Göteborg, en av få som professionellt arbetar med VIS i Sverige idag. Studien är kvalitativ och utgår från sex semistrukturerade intervjuer med Allwin och deras samarbetspartners. Uppsatsens resultat kan sammanfattas i fem slutsatser: 1) Att skänka livsmedel, med hjälp av svinnåtgärden VIS, innebär att nya värdekedjor skapas. 2) En professionalisering av VIS/Allwin har ökat förutsättningarna för en långsiktigt hållbar svinnåtgärd. 3) VIS/Allwin är pionjärer och drabbas av de svårigheter det innebär att trampa upp nya stigar. 4) Efterfrågan på VIS/Allwins tjänster kommer med all sannolikhet att öka. 5) VIS är en komplex åtgärd som kräver ett tydligt engagemang från alla inblandade parter, det finns därmed risk för att enklare lösningar prioriteras. / About a fourth of the climate impact originating from Swedish households can be derived from food, or rather from emissions caused in different stages of food production from field to fork. If food is being thrown away instead of being consumed the environmental impact has been in vain. The essay investigates CIW (Charity Instead of Waste, in Swedish VIS), a measure to deal with food losses where food is given to charity instead of becoming waste. The aim is to investigate how CIW functions and to contribute to increased knowledge on this, in Sweden, new way of responding to the problem with food losses. The strengths and weaknesses of CIW as well as the threats and opportunities that might be, have been examined by a SWOT-analysis. The company Allwin in Gothenburg is the concrete example of CIW that the essay is based on. The essay is a qualitative study with its starting point in six semi structured interviews with representatives from Allwin and its partners. The results of the essay can be summarized in five conclusions: 1) Donating food using CIW means that new value chains are created. 2) Allwin has gone from being a nonprofit organization to being a company. This professionalization has improved the conditions for making CIW a long term sustainable measure to deal with food losses. 3) CIW/Allwin are pioneers and have to deal with many difficulties related to breaking new ground. 4) The demand for services from CIW/Allwin is most likely to increase. 5) CIW is a complex measure, which requires a lot of engagement from all involved partners. This suggesting a risk that easier solutions could be prioritized.
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THE GEOMICROBIOLOGY OF SUSPENDED AQUATIC FLOCS: LINKS BETWEEN MICROBIAL ECOLOGY, FE(III/II)-REDOX CYCLING, & TRACE ELEMENT BEHAVIOURElliott, Amy V. C. 10 1900 (has links)
<p>This doctoral research comparatively assesses the biogeochemical properties of suspended aquatic flocs through a integrated field-laboratory approach; providing new insight into the linkages among floc associated bacteria, floc-reactive solid phases and trace metal uptake.</p> <p>Results show flocs to possess a distinct geochemistry, microbiology and composition from bed sedimentary materials in close proximity (III-oxyhydroxide minerals (FeOOH); resulting in localized floc-Fe-mineral precipitates and enhanced reactivity. Further, the Fe-enrichment of floc and of floc bio-mineral constituents in turn provides an important and novel lens through which to examine how environmental microbial communities, microbial metabolism and Fe<sup>III</sup>/Fe<sup>II </sup>redox transformations interact. The results were the discovery of floc-hosted, Fe<sup>III/II</sup>-redox cycling bacterial consortia across diverse oxygenated (O<sub>2</sub><sup>Sat.</sup>=1-103%) aquatic systems, which were not predicted to sustain bacterial Fe-metabolism. Both environmental<em> </em>and experimentally-developed consortial aggregates constituted multiple genera of aero-intolerant Fe<sup>III</sup>-reducing and Fe<sup>II</sup>-oxidizing bacteria together with oxygen consuming organotrophic species. These findings highlight that the implementation of geochemical thermodynamic constraints alone as a guide to investigating and interpreting microbe-geosphere interactions may not accurately capture processes occurring <em>in situ.</em></p> <p><em> </em> Seasonal investigation of microbial Fe<sup>III/II</sup>-redox transformations highlighted the interdependence of floc Fe-redox cycling consortia members, revealing that cold conditions and a turnover in putative Fe-reducing community membership extinguishes the potential for coupled Fe-redox cycling by wintertime floc bacteria. Further, the observed summer-winter seasonal turnover of <em>in situ</em> floc community membership corresponded with an overall shift from dominant Fe to S redox cycling bacterial communities. This significantly impacted observable floc Fe and TE (Cd, Pb) geochemistry, resulting in a shift in floc associated Fe-phases from dominantly Fe<sup>(III)</sup><sub>(s) </sub> to Fe<sup>(II)</sup><sub>(s)</sub>, and, in turn, corresponded to a large decrease of TE uptake by flocs under ice.</p> / Doctor of Science (PhD)
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Rapid Method of Processing Sperm for Nucleic Acid Extraction in Clinical Researchde Gannes, Matthew K 29 August 2014 (has links) (PDF)
Background: Sperm contain highly compact nuclei, inhibiting DNA extraction using traditional techniques. Current methods extracting sperm DNA involve lengthy lysis and no means of stabilizing DNA, hindering clinical research.
Objective: We sought to optimize an efficient method of extracting high quality human sperm DNA.
Methods: Sperm from three volunteers were isolated using PureCeption. We tested 1) proteinase K with DNA/RNA Shield, 2) DTT and TCEP as reducing agents, 3) QIAshredder homogenization, and 4) stability of sperm DNA fresh (baseline) or after 4 weeks of storage at 4OC in DNA/RNA Shield using modified Quick-gDNA MiniPrep. DNA was PCR amplified using ALU primers and digested with Hinf1 restriction enzymes. DNA methylation was measured by MassARRAY.
Results: DNA concentrations were similar with (30.1+0.28ng/μL, 33.4+0.21ng/μL) and without (28.9+0.00ng/μL, 30.9+0.85ng/μL) proteinase K. Sperm cells were lysed after 1 and 20 minutes with 25mM TCEP and 100mM DTT respectively. TCEP (50mM) produced greater DNA concentrations (17.2+0.50ng/μL, 21.3+0.71ng/μL) than 50mM DTT (12.6+0.28ng/μL, 12.3+0.35ng/μL). Adding QIAshredder to 50mM TCEP increased DNA concentrations (25.9+0.35ng/μL, 21.7+0.49ng/μL versus 18.6+0.99ng/μL, 12.3+0.35ng/μL). At baseline and 4 weeks: 1) DNA concentrations were similar (36.2+2.75 ng/μL, 32.2+1.38ng/μL, 44.3+3.93ng/μL versus 40.0+2.98ng/μL, 37.6+1.38ng/μL, 38.7+3.93ng/μL respectively) and 2) DNA was equally amplified by PCR and digested with restriction enzymes. DNA methylation was similar at baseline and 4 weeks for SNURF (1.43+1.02%, 1.55+0.95%), PEG10 (3.69+0.66%, 4.28+1.52%), and H19 (88.93+3.24%, 91.78+2.00%).
Conclusions: We stabilized and isolated high quality DNA from human sperm using 5 minute versus > 2 hour lysis in other methods. Our methods may facilitate efficient clinical research.
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The dynamics of microbial ferric and sulfate reduction in acidic mine lake sediments and their impact on water qualityPham, Huynh Anh January 2009 (has links)
[Truncated abstract] Acidic mine lakes are formed as a result of the oxidation and dissolution of metal sulfide minerals and are primarily characterized by low pH values of 2 4. Many strategies for the bioremediation of acidic mine lakes depend on the alkalinity generation capabilities of microbial ferric and/or sulfate reducing bacteria. However nearly all mine lakes are oligotrophic, with very low concentrations of available organic carbon and nutrients; all required for healthy microbial growth. There is also an unusual class of mine lakes characterized by low concentrations of organic carbon and also very low concentrations of dissolved iron and sulfate. Our ability to promote microbial activity in these systems is especially challenging. This study focuses on one of these systems, Lake Kepwari, a coal mine lake in Western Australia. Numerical modeling of remediation strategies is an efficient way of testing scenarios prior to expensive in-field trials. However such modeling relies on good descriptions of microbial processes, including kinetic parameterizations of ferric and sulfate reduction. There has been little research to date on the study of kinetic parameterizations of the chemical and biological alkalinity generation in acidic mine lakes. The objectives of this thesis were to investigate the viability of microbial ferric and sulfate reduction in an ultraoligotrophic, acidic mine lake, to assess the impact of these microbial processes on water quality and to parameterize the Dual Monod kinetics of neutralization under dual limitation conditions. Molecular analyses including most probable number, DNA extraction, polymerase chain reaction, polymerase chain reaction denaturing gradient gel electrophoresis were used to examine the microbial communities in the lake sediments. ... The Monod maximum specific microbial growth rates with respect to dissolved organic carbon and ferric, and as determined in batch experiments, were 0.07 ± 0.01 and 0.048 ± 0.02 day-1, respectively, and their corresponding Monod half saturation constants and were 14.37 and 5.6 mmol L-1. The Monod maximum consumption rates under ferric and OC limitation were also estimated. The Monod maximum specific microbial growth rates with respect to dissolved organic carbon and sulfate, , and were 0.05 ± 0.01, 0.08 ± 0.01 and 0.07 ± 0.02 day-1, respectively, and their corresponding Monod half saturation constants, and were 75.5, 131.8 and 10.2 mmol L-1. The Monod maximum consumption rates under sulfate and OC limitation were also estimated. The results of this study suggest that strategies for the remediation of ultraoligotrophic, acidic mine lakes may rely on microbial ferric and sulfate reduction, however additions of both organic carbon and sulfate/ferric are essential. These results can be immediately applied to mesocosm studies in outdoor enclosures and to the management of acidic mine lakes. Furthermore, this thesis has provided a new, valuable understanding on the Dual Monod kinetic parameterizations of neutralization for an ultraoligotrophic, acidic mine lake environment. These parameterizations are essential for the lake ecological models that will be used to investigate remediation scenarios for acidic mine lakes.
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在電腦施測情境中,促發、警告、時間限制對降低社會期許之效果 / Reducing social desirability bias of personality scale in computer administration mode: Effects of priming, warning, and time limit張軒正, Hsuan-cheng Chang Unknown Date (has links)
本研究欲探討在模擬甄選情境中,情境因素對降低社會期許之效果。本研究採三因子2×2×2受試者間之實驗設計,所操弄的三個獨變項為: 1.促發(priming)受試者誠實作答的傾向之有無 2.測謊題警告之有無 3.作答時間的限制之有無;依變項為社會期許正、負向題分數與三個人格測驗向度(適應性、親和性、審慎性)的分數。本研究分為研究一、研究二兩階段進行。研究一之受試者包括企業應徵者81人與國小實習老師92人,研究結果顯示:三個獨變項中,只在有「測謊題警告」情境下能顯著降低社會期許正向題的分數。「時間限制」則在無「促發」之情況下,會提升「親和性」人格之分數。針對研究一的結果,研究者改變「促發」與「時間限制」的操弄方式,其它研究程序相同,進行研究二。研究二之受試者為503位大學生,研究結果顯示:「促發」會提升社會期許負向題的分數,且在有「時間限制」、無「警告」的情況下,亦可提升「適應性」分數。「測謊題警告」可降低社會期許正向題的分數,並有降低「親和性」分數之趨勢。「時間限制」仍然沒有任何效果。
研究者分別就研究一、研究二之結果加以討論並提出可能的解釋。此外,研究者亦嘗試驗證與討論社會期許量表中正向題與負向題之建構。最後研究者檢討本研究之限制,並對未來之研究方向提出若干建議。 / The influence of three situational factors on reducing social desirability bias under simulated selection context was investigated in 2 studies. A 2×2×2 experimental design was used in these 2 studies. The three independent variables were: 1.’’Priming’’ the honest responding tendency. 2.Warning of having a lie scale. 3.Time limit for each question. The dependent variables included: 1.Two dimension scores of social desirability scale (positive keying items and negative keying items). 2.Scores of three personality dimensions (adjustment, likeability, prudence). Subjects of study1 were 81 job applicants and 92 elementary school interns. The results indicated that “warning of having a lie scale” could reduce the scores of positive keying social desirability scale. “Time limit” increased the scores of “likeability” under “no priming” situation. According to the results of study1, the author modified the manipulations of “priming” and “time limit”, and conducted study2. The subjects of study2 were 503 college students. The results indicated that “priming” could increase the scores of negative keying social desirability scale. “Priming” also increased the scores of “adjustment” under “time limit” and “no warning” situation. “Warning of having a lie scale” could reduce the scores of positive keying social desirability scale, and also had the trend to reduce the scores of “likeability”. “Time limit” still didn’t have any main effect on dependent measures.
Base on the results for study1 and study2, the author discussed the effects of 3 situational factors on reducing social desirability bias, and also tried to clarify the construct validity of two-dimensional social desirability scale. The author also discussed the limitations of the present research, and made some suggestions for future research.
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Speech recognition software: an alternative to reduce ship control manningKuffel, Robert F. 03 1900 (has links)
Approved for public release, distribution is unlimited / This study identifies factors affecting the performance of commercial-off-the-shelf speech recognition software (SRS) when used for ship control purposes. After a review of research in the feasibility and acceptability of SRS-based ship control, the paper examines the effects of: "A restricted vocabulary versus a large vocabulary," Low experience level conning officers versus high experience level conning officers, "Male versus female voices," Pre-test training on specific words versus no pre-test training. Controlled experimentation finds that: "The experience level of a conning officer has no significant impact on SRS performance." Female participants experienced more SRS errors than did their male counterparts. However, in this experiment, only a limited number of trials were available to assess a difference. "SRS with restricted vocabulary performs no better than SRS with large vocabularies." Using the software "correct as you go" feature may impact software performance. Following the user profile establishment, individual user training on two specific words reduces error rates significantly. This study concludes that SRS is a viable technology for ship control and merits further testing and evaluation. / Lieutenant, United States Navy
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