A geospatial analysis of Dengue fever in Cambodia from 2002 to 2012

Dengue fever has reemerged as a serious public health issue worldwide. The disease is endemic in more than 100 countries, with an estimated 50-100 million cases annually. It is considered endemic to Cambodia and, despite multiple control programs, the country has 10,000-40,000 hospitalized cases per year for children less than 15 years of age. In order to have control approaches that are more effective, the patterns of dengue cases in Cambodia need to be further explored. This study seeks to clarify the patterns of dengue by performing a geospatial analysis of 11 years of national surveillance data, from 2002 to 2012. Various exploratory geospatial statistical tools were used to calculate the local indicators of spatial autocorrelation and the local Gi* statistic analysis to determine significant hot and cold spots of dengue fever at the district level of Cambodia. Results found that in most years between 2002 and 2012, the two urban centers of Cambodia, Phnom Penh and Siem Reap, were significant hot spots for dengue fever. This suggests that prevention and control programs should be targeted to these two areas specifically. However, these clusters corresponded with five of the seven sentinel surveillance sites used in the country. This analysis could be only a representative of more sensitive surveillance. Expanding sentinel surveillance activities to other provinces could reveal a clearer picture of dengue fever in Cambodia

Influence of Student Discipline Referrals on School Climate in a K-12 Urban Public School District

Research indicates a connection between student discipline rates and school climate. In a large, urban K-12 public school district, student discipline concerns were increasing while school climate ratings were decreasing during the last few years. Guided by Bandura\u27s social learning theory, the purpose of this ex post facto, causal-comparative study was to identify differences in teachers\u27 perceptions of school climate, as measured by the New Teacher Project (TNTP) Insight Survey, between schools with high student discipline referral rates and schools with low student discipline referral rates in this school district. The study sample included 6,994 new and veteran certified teachers from N = 72 K-12 schools (n = 36 high discipline referral rate schools; n = 36 low discipline referral rate schools). Teachers\u27 TNTP ratings for Spring 2014-2016 on the overall school climate index, learning environment, and school leadership scales were the dependent variables for the analyses. Independent samples t test results indicated significant differences in overall school climate index, as well as the learning environment and school leadership scales for schools with high compared to low discipline referral rates. Findings showed that schools with high student discipline referral rates had more negative climate ratings than schools with low student discipline referral rates across the three TNTP scales for these teachers. These outcomes suggest that school leaders may create positive social change by identifying and implementing effective strategies aimed at improving student behavior and responses to student discipline as one possible means for fostering a more positive school climate which benefits students, teachers, and staff alike

You want me to do what? How Iowa’s secondary school principals are adjusting to their new roles in light of the Teacher Leadership Initiative

ABSTRACT In 2013 the Iowa Teacher Leadership and Compensation planning grant (TLC) committed to providing 150 million dollars annually toward rewarding effective teachers with leadership opportunities and higher pay, attracting promising new teachers with competitive starting salaries, and fostering greater collaboration for all teachers to learn from one another. One-quarter of each district’s teaching staff is now assuming a leadership role by assisting their colleagues in collecting meaningful student data, analyzing student achievement results, and utilizing the findings in order to improve teacher instruction (State of Iowa Department of Education, 2013). These leadership responsibilities had typically been attended to by the building principal, whose job description over the past decade has been shifting away from a traditional managerial position toward an instructional leadership role. While both principal and teacher leadership roles are defined by the Iowa Standards for School Leaders and the Iowa Teaching Standards, it remains unclear as to how these roles are enacted on a daily basis within the school. This study sought to gain a deeper understanding of principals’ viewpoints regarding the changes brought about by Teacher Leadership Initiative (TLI), and to understand how principals’ perceptions of their support from central office administration, including from the superintendent and central office administrators influenced the principals’ understanding of their roles as they navigated this change in leadership structure. Qualitative, semi-structured interviews with 12 secondary principals from Iowa schools were conducted on two separate occasions over a period of two months. Hall’s Concerns-Based Adoption Model (CBAM) served as the conceptual framework for this study as the researcher examined how principals managed change within their positions in order to enlighten and elucidate both the academic and mainstream reader on the complexities of the daily interactions among district-level staff, principals, and teacher leaders within various school contexts. Findings revealed that principals faced a spectrum of emotion as they implemented the teacher leadership initiative. Principals reported feeling optimistic and hopeful about the possibilities that teacher leadership holds for improved teaching and learning. However, they also expressed a variety of concerns as they worked through the steps of implementation. At times, principals experienced personal concerns such as anxiety, jealousy and isolation. Other times, principals felt unsure they had the necessary knowledge and skills to do the new work brought forth by teacher leadership. Principals reported feeling frustrated that there was never enough time in a day to complete their work. Still, in other instances, principals worried about whether teacher leadership was having a strong enough impact on teacher instruction and student learning that would justify the state funding allocated to the initiative. Principals expressed additional concerns related to the guidelines within the teacher leader initiative. They felt that some of the required elements provided obstacles to their work, causing them to hire unnecessary positions, or place teachers in positions that were not best aligned with the teachers’ knowledge and skills. The study found that principals were more likely to plan and implement initiatives from a building level, whereas, prior to teacher leadership, most of the professional development for teacher had originated at the district level. Finally, the study found that principals need ongoing support from central office administrators. Principals voiced the need for additional networking opportunities with other Iowa principals who are implementing teacher leadership, research-based resources that align with district initiatives, and recommended training for coaching teacher leaders. Principals believe these supports would assist them in implementing a teacher leadership program that improves teaching and learning in Iowa’s classrooms

The relationship between plants and their root-associated microbial communities in hydrocarbon phytoremediation systems

Phytoremediation systems for petroleum hydrocarbons rely on a synergistic relationship between plants and their root-associated microbial communities. Plants exude organic compounds through their roots, which increase the density, diversity and activity of plant-associated microorganisms, which in turn degrade hydrocarbons. Understanding the mechanisms driving this relationship poses one of the more intriguing challenges in phytoremediation research. This study was designed to address that challenge. Plant-microbe interactions in a weathered-hydrocarbon contaminated soil were examined under controlled growth chamber, and field conditions. In both environments single-species grass treatments initially facilitated greater total petroleum hydrocarbon (TPH) degradation than Medicago sativa (alfalfa), mixed species, or control treatments. In growth chamber studies increased degradation was linked to increased aliphatic-hydrocarbon degrader populations within the rhizosphere. Under field conditions, specific recruitment of endophytic aliphatic-hydrocarbon degraders in response to high TPH levels may have facilitated increased degradation by the grass Elymus angustus(Altai wild rye, AWR). AWR stably maintained these communities during times of local drought, enabling them to act as subsequent source populations for rhizosphere communities. The broad phylogenetic diversity of AWR endophytes, compared to the Pseudomonas-dominated communities of other plants, contributed to the observed stability. The relative composition of exudates released by plants also impacted both degradation activity and potential. Alfalfa released higher concentrations of malonate, which hindered degradation by decreasing metabolic activity and concomitantly inhibiting catabolic plasmid transfer. In contrast, AWR exudates contained high levels of succinate, which was linked to increased catabolic gene expression and plasmid transfer. A reciprocal relationship between exudation patterns and endophytic community structure likely exists, and both parameters have a specific influence on rhizosphere degradation capacity. In this study, grasses were more successful in maintaining the specific balance of all parameters required for the transfer, preservation, and stimulation of hydrocarbon catabolic competency

Sunny side up

A description of the author\u27s thesis project creating pots with a chicken motif, with the intention of conveying grace and Southern hospitality. Includes 18 slides of her thesis exhibition and a CD-ROM including many more images in .jpg format

Natural and experimental evolution of sexual conflict within Caenorhabditis nematodes

BACKGROUND: Although males and females need one another in order to reproduce, they often have different reproductive interests, which can lead to conflict between the sexes. The intensity and frequency of male-male competition for fertilization opportunities is thought to be an important contributor to this conflict. The nematode genus Caenorhabditis provides an opportunity to test this hypothesis because the frequency of males varies widely among species with different mating systems. RESULTS: We find evidence that there is strong inter- and intra-sexual conflict within C. remanei, a dioecious species composed of equal frequencies of males and females. In particular, some C. remanei males greatly reduce female lifespan following mating, and their sperm have a strong competitive advantage over the sperm of other males. In contrast, our results suggest that both types of conflict have been greatly reduced within C. elegans, which is an androdioecious species that is composed of self-fertilizing hermaphrodites and rare males. Using experimental evolution in mutant C. elegans populations in which sperm production is blocked in hermaphrodites (effectively converting them to females), we find that the consequences of sexual conflict observed within C. remanei evolve rapidly within C. elegans populations experiencing high levels of male-male competition. CONCLUSIONS: Together, these complementary data sets support the hypothesis that the intensity of intersexual conflict varies with the intensity of competition among males, and that male-induced collateral damage to mates can evolve very rapidly within populations

Multiscale, multimodal analysis of tumor heterogeneity in IDH1 mutant vs wild-type diffuse gliomas.

Glioma is recognized to be a highly heterogeneous CNS malignancy, whose diverse cellular composition and cellular interactions have not been well characterized. To gain new clinical- and biological-insights into the genetically-bifurcated IDH1 mutant (mt) vs wildtype (wt) forms of glioma, we integrated data from protein, genomic and MR imaging from 20 treatment-naïve glioma cases and 16 recurrent GBM cases. Multiplexed immunofluorescence (MxIF) was used to generate single cell data for 43 protein markers representing all cancer hallmarks, Genomic sequencing (exome and RNA (normal and tumor) and magnetic resonance imaging (MRI) quantitative features (protocols were T1-post, FLAIR and ADC) from whole tumor, peritumoral edema and enhancing core vs equivalent normal region were also collected from patients. Based on MxIF analysis, 85,767 cells (glioma cases) and 56,304 cells (GBM cases) were used to generate cell-level data for 24 biomarkers. K-means clustering was used to generate 7 distinct groups of cells with divergent biomarker profiles and deconvolution was used to assign RNA data into three classes. Spatial and molecular heterogeneity metrics were generated for the cell data. All features were compared between IDH mt and IDHwt patients and were finally combined to provide a holistic/integrated comparison. Protein expression by hallmark was generally lower in the IDHmt vs wt patients. Molecular and spatial heterogeneity scores for angiogenesis and cell invasion also differed between IDHmt and wt gliomas irrespective of prior treatment and tumor grade; these differences also persisted in the MR imaging features of peritumoral edema and contrast enhancement volumes. A coherent picture of enhanced angiogenesis in IDHwt tumors was derived from multiple platforms (genomic, proteomic and imaging) and scales from individual proteins to cell clusters and heterogeneity, as well as bulk tumor RNA and imaging features. Longer overall survival for IDH1mt glioma patients may reflect mutation-driven alterations in cellular, molecular, and spatial heterogeneity which manifest in discernable radiological manifestations

NASA's Functional Task Test: High Intensity Exercise Improves the Heart Rate Response to a Stand Test Following 70 Days of Bedrest

Cardiovascular adaptations due to spaceflight are modeled with 6deg head-down tilt bed rest (BR) and result in decreased orthostatic tolerance. We investigated if high-intensity resistive and aerobic exercise with and without testosterone supplementation would improve the heart rate (HR) response to a 3.5-min stand test and how quickly these changes recovered following BR. During 70 days of BR male subjects performed no exercise (Control, n=10), high intensity supine resistive and aerobic exercise (Exercise, n=9), or supine exercise plus supplemental testosterone (Exercise+T, n=8; 100 mg i.m., weekly in 2-week on/off cycles). We measured HR for 2 min while subjects were prone and for 3 min after standing twice before and 0, 1, 6, and 11 days after BR. Mixed-effects linear regression models were used to evaluate group, time, and interaction effects. Compared to pre-bed rest, prone HR was elevated on BR+0 and BR+1 in Control, but not Exercise or Exercise+T groups, and standing HR was greater in all 3 groups. The increase in prone and standing HR in Control subjects was greater than either Exercise or Exercise+T groups and all groups recovered by BR+6. The change in HR from prone to standing more than doubled on BR+0 in all groups, but was significantly less in the Exericse+T group compared to the Control, but not Exercise group. Exercise reduces, but does not prevent the increase in HR observed in response to standing. The significantly lower HR response in the Exercise+T group requires further investigation to determine physiologic significance

Molecular analysis of ethylene signal transduction in tomato

The plant hormone ethylene plays an important role in plant growth, development, and physiology. One of the critical components of the ethylene signal transduction pathway, ctr1 (constitutive triple response), was identified using a particularly useful seedling screen that takes advantage of the profound effects ethylene has on etiolated seedlings, known as triple response. CTR1 is one of six Arabidopsis MAPKKKs that are related to the Raf kinases, and acts as a negative regulator of ethylene response. In this study, isolation and characterization of a family of CTR1-like genes in tomato is reported. Based on amino acid alignments and phylogenetic analysis, the tomato CTR1-like (LeCTR) genes are more similar to Arabidopsis CTR1 (AtCTR1) than any other MAPKKK sequences in the Arabidopsis genome. The capacity of the LeCTR genes to function as negative regulators in ethylene signal transduction was tested through complementation of the Arabidopsis ctr1-8 mutant. Quantitative real-time PCR was carried out to generate an expression profile for the CTR1-like gene family during different stages of development marked by increased ethylene biosynthesis, including fruit ripening. The possibility of a multi-gene family of CTR1-like genes in other species besides tomato was examined through mining of EST and genomic sequence databases. Based on nucleotide and amino acid identity, At4g24480 is most similar to AtCTR1 and could potentially represent a CTR1-like gene in Arabidopsis. Arabidopsis plants carrying a T-DNA insert in the At4g24480 locus were examined for abnormal ethylene response phenotypes including sensitivity to other hormones, signal molecules and abiotic stresses. Two mutant alleles, ctr1-1 and ctr1-8, containing mutations that disrupt kinase activity and receptor association, respectively, were examined for sensitivity to these same treatments in an effort to better characterize ethylene hormone and non-hormone interactions. They also served as controls to determine if At4g24480 indeed possessed CTR1-like function. Arabidopsis and tomato represent species with very distinct fruit ripening/maturation programs. The critical dependence on ethylene for fruit ripening in tomato might have resulted in alteration or modification of the ethylene signal transduction pathway relative to Arabidopsis. Plans to characterize individual functions of the LeCTR genes through over-expression and reduced expression in tomato are outlined