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2016

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Evaluation Of Rescue Applications On Glyphosate-Resistant Palmer Amaranth, Andrew Boyette Denton Aug 2016

Evaluation Of Rescue Applications On Glyphosate-Resistant Palmer Amaranth, Andrew Boyette Denton

Theses and Dissertations

Options for glyphosate-resistant (GR) Palmer amaranth [Amaranthus palmeri (S. Wats)] control are becoming limited. Research was conducted in 2014 and 2015 to evaluate the effectiveness of rescue herbicide applications on glyphosate-resistant Palmer amaranth. Research was established to evaluate efficacy provided by new and current herbicide programs on GR Palmer amaranth that was larger than recommended at the time of herbicide application. Studies included a postemergence application of different herbicides used singly and in combination at different initial application timings; sequential postemergence application timing evaluating herbicide tank mix combinations at five different time intervals between applications; and postemergence evaluation of herbicide …

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Faster-X Evolution In The Speciation Of Heliconius Butterflies, Margarita Baquero Aug 2016

Faster-X Evolution In The Speciation Of Heliconius Butterflies, Margarita Baquero

Theses and Dissertations

The X and Z chromosomes have unique characteristics that lead to unique evolutionary consequences. Lepidopterans have a well-known, disproportionately large-Z effect for behavioral and morphological traits that distinguish closely related species. A potential explanation for the Large-X effect is the faster evolution of the sex chromosome (Faster-X evolution). We use whole genome re-sequencing of Heliconius erato races and of the incipient species H. himera to test for faster-Z evolution between hybridizing populations at different reproductive isolation levels, by calculating divergence and nucleotide diversity. We show evidence for Faster-Z evolution in Heliconius butterflies at the early stages of speciation and along …

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Adolescent Delinquency And Family Processes Among Single Parent Families, Sunmi Seo Aug 2016

Adolescent Delinquency And Family Processes Among Single Parent Families, Sunmi Seo

Theses and Dissertations

This study used secondary data from the National Longitudinal Study of Adolescent to Adult Health (Add Health) to examine the relationship between adolescent delinquency and family processes (i.e., relationship to residential parents and autonomy), among single-mother and singleather families. The findings indicate that adolescents in single-mother families reported a higher quality relationship to residential parents than those living with singleathers. Additionally, the relationship to residential parents variable was modestly predictive of adolescent delinquency. However, the results indicate there is no statistically significant difference between rates of adolescent delinquency among single-mother and singleather families. Research and practical implications of this study …

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What Really Works In Teacher Preparation Programs: Teachers' Self-Efficacy And Perceived Successful Methods After Participation In Mississippi's Career And Technical Education Alternate Route Program, Myra Carter Pannell Aug 2016

What Really Works In Teacher Preparation Programs: Teachers' Self-Efficacy And Perceived Successful Methods After Participation In Mississippi's Career And Technical Education Alternate Route Program, Myra Carter Pannell

Theses and Dissertations

The debate over the effective preparation of pre-service teachers is not new. Often this debate concerns what might be considered successful methods for all pre-service teachers. However, preparation for career and technical education (CTE) teachers could look quite different than that of academic teachers, whether they are prepared through traditional or alternative routes to education. In this qualitative study, the researcher examined two iterations of the alternative-route program designed to prepare new CTE teachers in Mississippi and considered the level of self-efficacy of the teacher participants, the perceived effectiveness of the specific elements of each program, and the perceived significance …

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Testing For A Functional Relationship Between Shell Rings And Flood-Prone Environments In The Yazoo Basin Of The Lower Mississippi Alluvial Valley, Tiffany Renee Raymond Aug 2016

Testing For A Functional Relationship Between Shell Rings And Flood-Prone Environments In The Yazoo Basin Of The Lower Mississippi Alluvial Valley, Tiffany Renee Raymond

Theses and Dissertations

The form and function of freshwater mussel shell rings in the Yazoo Basin was examined in this thesis. General and controlled surface collections, excavations, a seriation, and documentary research on flooding in the Yazoo Basin were completed. Four sites were investigated, including 22YZ513 (Rugby Farm), 22YZ605 (Light Capp), 22QU562 (Devil’s Race Track), and 22QU569 (Drew Smith), in an attempt to address whether shell rings were a functional byproduct of flood-prone environments. Results indicated that the two Quitman County sites were not shell rings, even though they appeared as such from aerial photographs, and that they represent a different ceramic cultural …

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Effects Of Dietary Lysine On Muscle Gene Expression And Fatty Acid Profiles And On Selected Carcass Characteristics And Plasma Hormone Concentrations In Late-Stage Finishing Pigs, Taiji Wang Aug 2016

Effects Of Dietary Lysine On Muscle Gene Expression And Fatty Acid Profiles And On Selected Carcass Characteristics And Plasma Hormone Concentrations In Late-Stage Finishing Pigs, Taiji Wang

Theses and Dissertations

Dietary inclusion of sufficient lysine is very critical for optimizing pig’s growth performance. The objectives of this project were to study the effects of dietary lysine at different concentrations on (1) the growth performance and carcass characteristics, (2) the muscle gene expression profile and the possible alterations to the metabolic and signaling pathways, (3) the muscle fatty acid profile, and (4) the plasma concentrations of growth-related hormones of late-stage finishing pigs. Nine crossbred barrows were assigned to 3 dietary treatments (lysine-deficient, equate, and -excess diets) according to a completely randomized experimental design. During the 5-week feeding trial, pigs were allowed …

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Asteroid Redirect Mission (Arm) Using Solar Electric Propulsion (Sep) For Research, Mining, And Exploration Endeavors Of Near-Earth Objects (Neos), Torrey Paul Harriel Aug 2016

Asteroid Redirect Mission (Arm) Using Solar Electric Propulsion (Sep) For Research, Mining, And Exploration Endeavors Of Near-Earth Objects (Neos), Torrey Paul Harriel

Theses and Dissertations

The feasibility of relocating a small (~500,000 kg) Near-Earth Asteroid (NEA) to High Earth Orbit via Solar Electric Propulsion (SEP) is evaluated with the orbital simulation software General Mission Analysis Tool (GMAT). Using prior research as a basis for the mission parameters, a retrieval mission to NEA 2008 HU4 is simulated in two parts: approach from Earth and return of the Asteroid Redirect Vehicle (ARV) with the asteroid in tow. Success of such a mission would pave the way for future missions to larger NEAs and other deep space endeavors. It is shown that for a hypothetical launch time of …

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Cogongrass [Imperata Cylindrica (L.) Beauv.] Control Using Chemical Treatment With Cover Cropping Systems, Maria Leticia Moraes Zaccaro Aug 2016

Cogongrass [Imperata Cylindrica (L.) Beauv.] Control Using Chemical Treatment With Cover Cropping Systems, Maria Leticia Moraes Zaccaro

Theses and Dissertations

Cogongrass management generally requires multiple herbicide applications, however, success is limited if not integrated with other methods. Experiments were conducted to evaluate the use of cover cropping systems with herbicides on cogongrass control. Field studies determined that sequential glyphosate applications in the summer were necessary to achieve 80% or greater control, but a single application could be effective if weather conditions allowed early planting and good cover crop establishment of Roundup Ready soybeans. Studies also indicated that the use of ALS-resistant Italian ryegrass and white clover crop combinations showed no effect, but imazapyr applications made in May or June provided …

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Design Of An American Football Helmet Liner For Concussion Mitigation, Gustavus Alston Rush Aug 2016

Design Of An American Football Helmet Liner For Concussion Mitigation, Gustavus Alston Rush

Theses and Dissertations

The objective of this research was to develop an optimal design for a polymeric American football helmet liner for concussion prevention utilizing experiments and high performance. Along with well-established injury criteria (HIC, SI, and Peak acceleration), localized brain injury mechanisms were explored by employing Finite Element simulations and experimental validation. Varying strain rate experiments (monotonic and hysteresis) were conducted on modern football helmet (Rush, Rawlings, Riddell, Schutt, and Xenith) liners and new possible polymeric foam liner materials. These experiments were used to characterize each material at low strain rates (0.1/sec; Instron), intermediate strain rates (100-120/sec; NOCSAE drop tower) and high …

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Effects Of Feed Additive Inclusion Strategies On Male Heavy Broiler Performance, Rosana Akemi Hirai Aug 2016

Effects Of Feed Additive Inclusion Strategies On Male Heavy Broiler Performance, Rosana Akemi Hirai

Theses and Dissertations

Past literature has supported the supplementation of 25-OHD3 into poultry diets to reduce leg issues and improve muscle accretion. In addition, exogenous feed enzymes are included into poultry diets to increase nutrient utilization. The first objective of this thesis was to determine the effects of different sources and levels 25-OHD3 supplementation on D0-53 Ross x Ross 708 male broiler performance, processing yield, tibia ash, serum Ca and 25-OHD3 status. Data demonstrated that 25-OHD3 supplementation into diets with Low VitD3 (165 IU/kg) can improve broiler performance compared to High VitD3 (2756 IU/kg). The second objective was to investigate the effects of …

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Development Of Assisted Reproductive Technologies For Endangered North American Salamanders, Ruth Marie Marcec Aug 2016

Development Of Assisted Reproductive Technologies For Endangered North American Salamanders, Ruth Marie Marcec

Theses and Dissertations

Amphibians are key health indicator species and important sentinels for ecosystem health. With 32% of amphibians threatened with extinction, and an additional 25% without enough data on record to fully understand their status, amphibians are facing what is being called the Amphibian Extinction Crisis. Of caudate amphibians (salamanders/newts), 49.8% are threatened or endangered, making them currently the most threatened vertebrate taxa. As a result of the Amphibian Extinction Crisis, it is imperative that captive breeding facilities be established as a hedge against future amphibian extinctions. Unfortunately, captive assurance colonies face frequent failure due to lack of natural stimuli, which are …

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Drivers Of Sustainable Agriculture In A Southern State, Casey William Odom Aug 2016

Drivers Of Sustainable Agriculture In A Southern State, Casey William Odom

Theses and Dissertations

This Master’s Thesis establishes what motivates a group of Mississippi farmers to participate in sustainable agriculture instead of industrial agriculture. A database of sustainable farmers was constructed in collaboration with the Gaining Ground Sustainability Institute of Mississippi. This research project used social network analysis with 28 farmers and participant observation and semi-structured interviewing with a purposively selected sample of 14 farmers. This project also explores the sustainable agricultural practices of participants. A map of the social network of sustainable agriculturalists in Mississippi is presented and shows that some farmers are well connected, some moderately connected, and others are isolated. As …

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Influence Of Velocity On Weimaraner Trotting Mechanics, Leif Carlisle Aug 2016

Influence Of Velocity On Weimaraner Trotting Mechanics, Leif Carlisle

Theses and Dissertations

While Weimaraner size may assist in the performing of tasks of a sporting dog, it also makes the breed more susceptible to hip dysplasia. However, this breed has a lower rate of dysplasia. This may be due to selected gait velocity and mechanics specific to the breed, but gait analysis of Weimaraners is lacking. Study objectives were to define normal trotting mechanics and to determine the influence of velocity on gait. Dogs were trotted at a slow and fast trot and at both velocities. The trot had a diagonal footfall sequence with a 2-beat rhythm alternating between diagonal bipedal support …

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Journey To The Unconscious: An Examination Of Paths To Enlightenment In Hermann Hesse's Works, Victoria B. Lee Aug 2016

Journey To The Unconscious: An Examination Of Paths To Enlightenment In Hermann Hesse's Works, Victoria B. Lee

Theses and Dissertations

Over the course of this thesis, three of Hermann Hesse’s novels will be examined – Demian (1919), Der Steppenwolf (1927), and Siddhartha (1922) – as performative texts in order to demonstrate how Hesse presents a blueprint of ideal paths to personal enlightenment through common themes that flow through his works, such as breaking out, creation and destruction, and Jungian archetypes. These themes will be compared to Nietzsche’s work on the transformation of the soul. Each of these performative texts by Hesse present a unique opportunity, not only to enjoy a masterful tale of such vivid characters, but also a chance …

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Landscape Ecology Of Eastern Wild Turkeys In Mississippi, Annie Moriah Davis Aug 2016

Landscape Ecology Of Eastern Wild Turkeys In Mississippi, Annie Moriah Davis

Theses and Dissertations

The effects of landscape structure on wildlife populations have drawn more attention from ecologists and wildlife managers as landscapes have rapidly changed worldwide. The objectives of this study were to (1) conduct a statewide habitat suitability assessment for wild turkeys (Meleagris gallopavo) in Mississippi using machine learning methods; (2) determine landscape-abundance relationships of wild turkeys at 2 spatial scales; and (3) measure genetic distinction of wild turkey populations in Mississippi. I found that habitat suitability for wild turkeys was positively related to amount of forest cover. Wild turkey relative abundance peaked at an optimal hardwood forest proportion of 0.29 and …

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A Novel Microextraction Method For Determining The Presence Of Pentachlorophenol In An Ongoing In-Situ Groundwater Remediation, Julianna Nicole Stratton Aug 2016

A Novel Microextraction Method For Determining The Presence Of Pentachlorophenol In An Ongoing In-Situ Groundwater Remediation, Julianna Nicole Stratton

Theses and Dissertations

Pentachlorophenol (penta) is a pollutant of concern worldwide. This study looks at a site that has been under remediation for the last 16 years due to penta contamination. The site has been air- and bio-sparged, phytoremediated and undergone in-situ chemical oxidation treatment in attempts to clean the ground water of penta. This thesis explores a novel microextraction method that has the promise of being more sensitive using less sample and fewer hazardous chemicals than conventional methods. Groundwater samples were extracted for phenolic compounds using a novel modified liquid microextraction protocol. Comparing our results with monitoring information from 2014, our method …

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The Defense Response Of Glycine Max To Its Major Parasitic Nematode Pathogen Heterodera Glycines, Shankar R. Pant Aug 2016

The Defense Response Of Glycine Max To Its Major Parasitic Nematode Pathogen Heterodera Glycines, Shankar R. Pant

Theses and Dissertations

Heterodera glycines, soybean cyst nematode (SCN) causes more than one billion dollars soyben production loss in the U.S. annually. SCN is an obligate parasite of specialized feeding cells within the host root known as syncytium. The SCN resistance genes and signaling pathways in soybean have not been fully characterized. Gene expression analysis in syncytium from compatible and incompatible interactions identified candidate genes that might involve conferring resistance to SCN. This dissertation aimed to investigate the biological functions of the candidate resistance genes to confirm the roles of these genes in resistance to SCN. The study demonstrated a role of syntaxin …

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The Role Of Auxin In Defense Response To Aspergillus Flavus In Zea Mays L, Seval Ozkan Aug 2016

The Role Of Auxin In Defense Response To Aspergillus Flavus In Zea Mays L, Seval Ozkan

Theses and Dissertations

Understanding the role of phytohormone auxin in defense responses is one of the vital tools for plant breeders to develop maize germplasm lines that exhibit high resistance to Aspergillus flavus and subsequent aflatoxin accumulation. Besides its critical role in different developmental processes throughout the life cycle of plants, auxin is also involved in the network of plant-pathogen interaction as demonstrated in previous studies. However, the actual mechanism for the auxin signaling pathway leading to resistance is unknown. Therefore, the critical gap in the knowledge base is a lack of understanding of the role of auxin signaling in pathogen resistance in …

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Investigating Late Woodland-Period Aquatic Catchments Through Freshwater Mussel Assemblage Composition, Sarah K. Gilleland Aug 2016

Investigating Late Woodland-Period Aquatic Catchments Through Freshwater Mussel Assemblage Composition, Sarah K. Gilleland

Theses and Dissertations

During the Late Woodland Period in the American Southeast, the amount of space that any individual group could exploit began to shrink, due to the presence of other groups on the landscape. Resource expansion occurred to augment food supplies, resulting in increased exploitation of mussel beds. Because mussels can be extremely sensitive to the characteristics of the waterways they live in, the specific habitat requirements of these animals can be used to reconstruct the environments they were recovered from. In this thesis I use freshwater mussel assemblages to reconstruct hypothetical aquatic catchments and map them onto modern rivers in the …

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Isotopic Study Of Diet During The Bronze And Early Iron Ages At Mitrou And Tragana Agia Triada, Greece, Stephanie Fuehr Aug 2016

Isotopic Study Of Diet During The Bronze And Early Iron Ages At Mitrou And Tragana Agia Triada, Greece, Stephanie Fuehr

Theses and Dissertations

The stable isotopes carbon and nitrogen from 18 skeletal and 51 dental samples from various burial contexts at the Bronze and Iron Age sites of Mitrou and Tragana Agia Triada are examined to understand diet in prehistoric central Greece. The samples are compared by cultural period, site, and burial type in order to determine if diet was affected by changes in society or by social status as determined by burial form. In addition, isotopic data from across Greece is compared to understand diet from the Neolithic to Iron Age and in different regions of the country. The results of the …

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Methodology To Measure And Compare The Efficiency Of Radiant Heaters Used In Poultry Brooding, John Emerson Linhoss Aug 2016

Methodology To Measure And Compare The Efficiency Of Radiant Heaters Used In Poultry Brooding, John Emerson Linhoss

Theses and Dissertations

During the first seven to ten days of life chicks are unable to maintain homeothermy, thus providing supplemental heat is critical to their livability and performance. Radiant heaters are the preferred method of providing heat during brooding because they provide a range of thermal comfort options for chicks. Infrared thermography is often used to assess the heat distribution created at the litter surface by radiant heaters. The resulting images provide a good qualitative assessment of heat distribution but do not provide any quantifiable metrics through which to compare the radiant output of heaters. Data acquisition systems were developed to measure …

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Relative Rate Of Transposable Element Insertions On The X Chromosome And Autosomes, Christopher D. Savell Aug 2016

Relative Rate Of Transposable Element Insertions On The X Chromosome And Autosomes, Christopher D. Savell

Theses and Dissertations

Sex chromosomes and autosomes often differ in their relative rates of evolution, with sex chromosomes generally accumulating changes more rapidly (faster-X evolution). Transposable elements (TEs) make up a significant portion of eukaryotic genomes and are some of the most rapidly evolving genetic elements. We compared relative rates of insertion on the X and autosomes for 78 families found in Drosophila melanogaster. The average X/A ratio for these TE families was 1.11, similar to the mean dS X/A ratio, indicating no male-bias in mutation rate or TE insertion. The major mode of the distribution was ~0.8, indicating stronger purifying selection on …

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Follicular Waves And Their Impact On The Dominant Follicle, Uterus, And Subsequent Pregnancy Rates In Beef Cattle, Ashleigh Marie Muth-Spurlock Aug 2016

Follicular Waves And Their Impact On The Dominant Follicle, Uterus, And Subsequent Pregnancy Rates In Beef Cattle, Ashleigh Marie Muth-Spurlock

Theses and Dissertations

Ovarian steroids assist in the development of the follicle and its enclosed oocyte as well as prepare the maternal environment for pregnancy. The objective of experiment 1 was to elucidate the differences between dominant follicles of each follicular wave in terms of intraollicular concentration of steroids after 4 d of dominance. Differences in blood perfusion between the dominant follicle of the first and second non-ovulatory wave were also examined. Follicular waves were monitored daily via ultrasonography from emergence to aspiration of the dominant follicle. It was determined that although the dominant follicles aspirated from ovulatory waves possessed a greater concentration …

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From Horns To Helmets: Multi-Objective Design Optimization Considerations To Protect The Brain, Kyle Leslie Johnson Aug 2016

From Horns To Helmets: Multi-Objective Design Optimization Considerations To Protect The Brain, Kyle Leslie Johnson

Theses and Dissertations

This dissertation presents an investigation and design optimization of energy absorbent protective systems that protect the brain. Specifically, the energy absorption characteristics of the bighorn sheep skull-horn system were quantified and used to inform a topology optimization performed on a football helmet facemask leading to reduced values of brain injury indicators. The horn keratin of a bighorn sheep was experimentally characterized in different stress states, strain rates, and moisture contents. Horn keratin demonstrated a clear strain rate dependence in both tension and compression. As the strain rate increased, the flow stress increased. Also, increased moisture content decreased the strength and …

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Bayesian Networks To Assess The Newborn Stool Microbiome, William E. Bennett Jr. Aug 2016

Bayesian Networks To Assess The Newborn Stool Microbiome, William E. Bennett Jr.

McKelvey School of Engineering Graduate Student Theses & Dissertations

In human stool, a large population of bacterial genes and transcripts from hundreds of genera coexist with host genes and transcripts. Assessments of the metagenome and transcriptome are particularly challenging, since there is a great deal of sequence overlap among related species and related genes. We sequenced the total RNA content from stool samples in a neonate using previously-described methods. We then performed stepwise alignment of different populations of RNA sequence reads to different indices, including ribosomal databases, the human genome, and all sequenced bacterial genomes. Each pool of RNA at each alignment step was subjected to compression to assess …

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Novel Ph-Sensitive Cyclic Peptides, Dhammika Weerakkody, Anna Moshnikova, Naglaa Salem El-Sayed, Ramona-Cosima Adochite, Gregory Slaybaugh, Jovana Golijanin, Rakesh Tiwari, Oleg A. Andreev, Keykavous Parang, Yana K. Reshetnyak Aug 2016

Novel Ph-Sensitive Cyclic Peptides, Dhammika Weerakkody, Anna Moshnikova, Naglaa Salem El-Sayed, Ramona-Cosima Adochite, Gregory Slaybaugh, Jovana Golijanin, Rakesh Tiwari, Oleg A. Andreev, Keykavous Parang, Yana K. Reshetnyak

Pharmacy Faculty Articles and Research

A series of cyclic peptides containing a number of tryptophan (W) and glutamic acid (E) residues were synthesized and evaluated as pH-sensitive agents for targeting of acidic tissue and pH-dependent cytoplasmic delivery of molecules. Biophysical studies revealed the molecular mechanism of peptides action and localization within the lipid bilayer of the membrane at high and low pHs. The symmetric, c[(WE)4WC], and asymmetric, c[E4W5C], cyclic peptides translocated amanitin, a polar cargo molecule of similar size, across the lipid bilayer and induced cell death in a pH- and concentration-dependent manner. Fluorescently-labelled peptides were evaluated for targeting of acidic 4T1 mammary tumors in …

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Universal Modes Of Awareness? A “Pre-Reflective” Premise, Uta M. Jürgens Aug 2016

Universal Modes Of Awareness? A “Pre-Reflective” Premise, Uta M. Jürgens

Animal Sentience

Mark Rowlands holds that creatures endowed with pre-reflective awareness may qualify as persons: In pre-reflective awareness, the self and the unity of mental life are implicit in the stream of experience. Rowlands generalizes from an introspective analysis of pre-reflective consciousness in humans to pre-reflective awareness in general. I describe three examples of empirical findings that corroborate the assumption that animal minds have some of the same basic modes of pre-reflective awareness as human minds.

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Full Issue, Children's Book Review Aug 2016

Full Issue, Children's Book Review

Children's Book and Media Review

No abstract provided.

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Emmaline And The Bunny, Marsha D. Broadway Aug 2016

Emmaline And The Bunny, Marsha D. Broadway

Children's Book and Media Review

No abstract provided.

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Critter Sitter, Tessa Mcmillan Aug 2016

Critter Sitter, Tessa Mcmillan

Children's Book and Media Review

No abstract provided.

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