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Egr3-Â/-Â Mice, a Mouse-Model of Schizophrenia, Show Decreased Levels of Htr2a mRNA in the Anterior Frontal Cortex after Sleep Deprivation Compared to WT Mice
A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine.In the U.S., 1 in 25 adults experience serious mental illness each year. Despite ongoing research efforts, the pathogenesis of schizophrenia remains unknown. The aim of this study is to answer the question “Do Egr3-Â/- mice, a mouse-Âmodel of schizophrenia, show decreased levels of Htr2a mRNA in the prefrontal cortex (PFC) region of the brain after sleep deprivation (SD) compared to wild type (WT) mice?” Data resulting from the study will shed light on the pathogenesis of such a disabling mental disorder. Our study investigates the interaction between two of the genes linked to increased risk of schizophrenia, the early growth response (Egr) 3 gene and Htr2a, which encodes the serotonin 2a receptor (5HT2AR) in response to SD, a form of stress. We used a cohort of age-Âmatched pairs of C57BL/6 Egr3-Â/- and WT male mice. Half of these underwent a SD protocol, while the other half served as a control group. Htr2a mRNA was quantified in four different brain regions via densitometry after it was visualized using in-Âsitu hybridization. Our findings that Egr3-Â/- mice show statistically significant decreased expression levels of Htr2a mRNA in the PFC support our proposed biological pathway for schizophrenia risk.This item is part of the College of Medicine - Phoenix Scholarly Projects 2019 collection. For more information, contact the Phoenix Biomedical Campus Library at [email protected]
Spectroscopic and Computational Electronic Structure Studies of Donor-Acceptor Systems
Three molecular systems have been studied, which exhibit strong intramolecular electronic communication between constituent moieties. Experimental results for electronic absorption, resonance Raman, electron paramagnetic resonance (EPR), and magnetic circular dichroism (MCD) spectroscopies are presented. Density functional theory (DFT) electronic structure calculations were employed to augment the interpretation of experimental results. Using a valence bond configuration interaction (VBCI) model we show that the ground state properties of the molecules are influenced by excited state configurations. Donor ( = semiquinone)-bridge-acceptor ( = nitronylnitroxide) biradicals show strong ferromagnetic donor-acceptor coupling, and contributions to the ferromagnetic coupling from spin delocalization and spin polarization mechanisms are discussed. We explore effects of bridge substitutions on donor-acceptor coupling, where the bridge can be phenyl, thiophene, biphenyl, bithiophene, xylene, or other sterically hindered phenyl-derivatives. Meta connectivity of the Donor and Acceptor on a phenyl bridge results in antiferromagnetic donor-acceptor coupling, while para connectivity results in ferromagnetic exchange coupling. In this dissertation we discuss in detail the mechanisms for the observed exchange coupling. The heterobimetallic active site of the carbon monoxide dehydrogenase (CODH) enzyme catalyzes the oxidation of carbon monoxide to carbon dioxide in presence of water. Mechanisms presented in the literature differ in their description of how the [MoSCu] unit functions to catalyze CO oxidation. Computational and spectroscopic studies of synthetic CODH active site models show that electronic transitions below ~27000 cm-1 are Cu → Mo charge transfer in nature, and the observation of large isotropic Cu hyperfine coupling to the Mo(V) confirms the importance of Cu \u2192 Mo charge transfer excited states to covalency within the [MoSCu] unit. The large covalency across the [MoSCu] unit in both the enzyme and models points to a likely role of the [MoSCu] unit in the transfer of electrons between CO and Mo(VI). Calculated geometric and electronic changes for CO binding to the Cu(I) site are discussed. The Re2X4(PMe3)4PF6 compounds (X = Cl, Br) are highly symmetric Re dimers with a bond order of 3.5 that includes a partial δ bond. Spectroscopic and computational data of the δ→δ* band show that the contribution of the δ bond to the Re-Re bonding is small. Bonding calculations show that antibonding interactions of the halide and trimethylphosphine ligands with the Re d-orbital manifold dictate the energetic ordering of the Re d-orbitals
Administrator Perceptions on Service Strengths and Challenges regarding the Implementation of Section 504 Services for Public Education Students in South Texas
As part of their contemporary role as the campus instructional leader, administrators are currently managing special education matters previously managed by the school system’s directors of special education [(Boscardin, 2005; Patterson, Marshall, & Bowling, 2000) cited by Lynch, 2012]. School administrators must not only understand the legal requirements of Section 504, but they must understand how Section 504 services will influence their programs, decisions, facilities, and budgets (Trevino, 2001, p. 87). At a time of economic constriction and change, complying with the unfunded mandate of Section 504 and the Americans with Disabilities Act Amendment Act presents a challenge to K-12 public schools (Zirkel, 2009 b, p.260). In an era of accountability which includes meeting progress standards on state mandated assessments, school administrators must be able to meet the needs of a growing population and sufficiently allocate resources so that eligible Section 504 students are assured the provision of a free and appropriate public education (FAPE). This study examined perceptions of current public school administrators in elementary and secondary educational settings regarding strengths and challenges in district Section 504 services. The researcher’s intent was to add to the body of knowledge regarding what policy and procedures need to be further examined regarding students with disabilities receiving Section 504 Only services. The review of the literature reflected the current increase in the number of students that meet the eligibility criteria for Section 504 accommodations and services when applying the new standards to the evaluation process under Section 504 in K-12 public education. The selected survey instrument used to collect data from the participants was an adapted version of the Section 504 School Based Administrator Survey Blueprint (Maydosz, 2009). The rationale for utilizing a survey design was due to the type of data needed in regards to quantifying descriptions of perceptions and opinions of selected participants in the study. Data collection consisted of disseminating online surveys to administrative personnel of two large and three small school districts who participate in the Section 504 decision making processes for their respective campuses in a regional area of South Texas
Sustainable food waste management through the integration of anaerobic digestion and thermochemical processes
The processing of food waste along with animal manure through anaerobic digestion (AD) is a popular waste management strategy. However, there is the concern that with the proliferation of AD the management of its nutrient-rich effluent, known as digestate, becomes a challenge. Current digestate management practices not only present environmental risks, but also issues related to the seasonality of field spreading and the storage and transportation of large volumes of material. The integration of the AD process with thermochemical conversion (TC) could help reduce some of these issues. The production of biochar from materials already available in the digester setting, such as the solid fractions of digestate and dairy manure, could be used to recover the phosphorus present in the liquid fraction of the effluent. The resulting phosphate enriched biochar will finally be applied as an alternative fertilizer. Both solid digestate and solid manure biochar were produced through pyrolysis at three different temperatures (500, 800, and 1000ËšC). To assess the suitability of biochar as a soil amendment, we performed a complete characterization of the material based on the standard proposed by the International Biochar Initiative (IBI). For evaluating biochar as an adsorption medium, phosphate adsorption was tested using a synthetic solution and the effluent from the actual anaerobic co-digestion process. The environmental benefits and drawbacks of combining these two technologies were evaluated using life cycle assessment (LCA) methodology. Results showed that the amount of solid digestate biochar produced is sufficient to adsorb approximately 20% of the total phosphate present in the liquid fraction of the digestate. While, solid manure biochar has the potential to fulfill the site requirements to adsorb most of the phosphate in a synthetic solution but not actual digestate. The LCA results show that the combination of technologies could reduce the impacts to freshwater, only if most of the phosphate present its recovered into the biochar
Attachment, Marriage Beliefs, and Sense of Identity among Unmarried College Students
Attachment styles often reveal what individuals personally value within themselves and others. In this study, that idea was explored through the attachment styles, restrictiveness of marriage views, and sense of identity through the condition of marital status (whether in a relationship or not) of 106 unmarried undergraduate students from La Salle University. It was hypothesized that marital status would moderate the variance in the restriction of marriage views due to attachment style (secure, preoccupied, dismissing, or fearful), and that marital status would also moderate the differences in attachment styles accounted for by identity. The results showed that the variance in certain marriage views (cohabitation, “love is enough,” “one and only,” were accounted for by attachment style and marital status, but that differences in attachment styles were not accounted for by identity through the moderation of marital status. However, the variance in each of the attachment styles were either accounted for by either marital status or identity
INFLUENZA A VIRUSES OF SWINE IN WESTERN CANADIAN PIGS AND PEOPLE
Influenza A viruses (IAV) are well-known for their zoonotic potential, and the health and
economic threats they pose to humans and pigs. The complexity of influenza virus ecology
involving genetically variant viral strains and several natural hosts means that the virus
continuously challenges the host-species barrier. Surveillance of IAV is essential as it provides
helpful information that can lead to a better understanding of the behavior of the virus at the
animal-human interface, the risk factors and the key genetic changes that allow the virus to cross
the species barrier. The research aimed to compare the suitability of samples collected for the
detection of IAV in swine and to identify the epidemiological and viral factors that might play a
fundamental role in the human-swine interface of transmission. The suitability of three types of
samples for the detection of IAV in pigs, nasal swabs (NS), oral fluids (OF) and oral swabs (OS),
was compared. IAV Matrix gene PCR results showed NS were the most effective method of IAV
detection in swine. Compared to NS, OS had a relative sensitivity of 43.6% to 43.8% and relative
specificity of 99.3% to 100%. The relative sensitivity and specificity of OF was 57.1% and
95.5%, respectively. Furthermore, the degree of agreement between NS and the other two
samples was moderate (k = 0.531-0.583, p < 0.001). Human-swine transmission was evaluated
through a pilot project consisting of active surveillance in both swine workers and pigs from 11
farms in Western Canada. Nasal swabs, OS, and surveys assessing flu-like symptoms were
collected from 26 swine workers and results were compared with Matrix real-time reverse
transcriptase PCR (RT-qPCR) results from swine nasal swabs. There was no statistically
significant correlation between the clinical symptoms in humans and the RT-qPCR results from
swine samples. However, the IAV Matrix gene PCR results from the NS and OS of the swine
workers had a very weak correlation with the results found in swine (r = 0.182-0.200, p = 0.024-
0.040). Transmission among species was not confirmed, but samples with suspect results from
human samples coincided with positive swine pool results and the presence of an Alpha H1N2
virus in 4 farms, which is suggestive of a common link between humans and pigs for IAV
EvaluaciĂłn probabilĂstica del peligro por lahares en el flanco NE del Volcán PopocatĂ©petl
This study shows the results of a probabilistic evaluation
of laharic hazard to Santiago Xalitzintla, locality
in Puebla, at the NE flank of the Popocatépetl volcano
in MĂ©xico. The TITAN2F software was used for
lahars modeling. The program forecasts were compared
with data obtained in the field for the laharic event of
2001 in order to evaluate the reliability of its use on
a digital elevation model. The results obtained with
TITAN2F are comparable with information reported
previously in other studies of this lahar; coming to the
conclusion that modeling with TITAN2F is reliable.
This investigation provides a useful tool for the knowledge
of laharic hazards. Also, it shows the probability
of the affected area by inundation as well as the probability
distribution of dynamic-pressure levels, which is
an important parameter for assessment risk in a lahar
flow.
To make a probabilistic analysis is required a number
of statistically representative hypothetic scenarios, covering
all possible cases. According to historical events
recorded, two possible sources for a laharic flow were defined,
and they correspond to the Huiloac and Alseseca
gorges. Based on the geological information, the ranges
of initial conditions that TITAN2F requires (velocity,
concentration and volume) were defined for each one of
the basins.
A stratified sampling was carried out using the Latin
Hypercube method (LHS). This method generates a
representative sample of hundreds of combinations from
the initial conditions, in order to modeling laharic events
with TITAN2F. The probabilistic analysis was made
through Bayesian inference, and programming routines
in OCTAVE. The probabilistic distribution indicates
that there is a nearly 80 % probability to be reached
by lahars at community areas of Santiago Xalitzintla.
However it is characterized by low dynamic-pressure
levels. The final section of the Huiloac gorge was
identified as a critical zone, where the probability that
dynamic-pressures surpassing destructive levels is high
Exploring the benefits of a traveller clustering approach based on multimodality attitudes and behaviours
This paper presents a new market segmentation study of travellers based on measures of multimodality attitudes and behaviours. The study involved a sample of researchers and clerical workers of the French national transport research institute to allow for a long and detailed questionnaire on multimodality habits. Two different cluster analyses are implemented. The first one considers variables related to the specific trip that was investigated in the survey, namely the intention to make such trip with changing travel means over time and the propensity to use a different mode in the future. The second study focuses on the more general multimodality behaviour, contemplating the actual and desired frequencies of use of different means and the propensity to try new services that are not yet existing in reality. The resulting market segments are compared and they are consistently pointing at almost the same classification of travellers. The best transport policy measures to achieve a behavioural change for each market segment are discussed
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