Does a Co-Learner Delivery Model in Professional Development Affect Teachers’ Self-Efficacy in Teaching Mathematics

A mixed method study is reported examining teacher efficacy regarding professional development in mathematics instruction for two groups of teachers: in building with peers (N=17) and MAT student co-learners in the classroom (N=14). An end-of-course survey, focus group interviews and pre-post data for the Teacher Self Efficacy Scale were used to investigate:1. What is the difference in teachers’ efficacy regarding mathematics instruction based on the professional development delivery system they experienced? 2. What are teachers’ perceptions of their professional development with peers conducted onsite in district compared with professional development with peers and preservice teachers at a university setting? Descriptive statistics, t-tests, ANCOVA, and thematic analysis were used. While the co-learner teachers tended to have higher self efficacy scores, the adjusted posttest means were not statistically different. Thematic analysis indicated that both groups were positive in their evaluations of their professional development. Implications for professional development are discussed

Does a Co-Learner Delivery Model in a Mathematics Methods Course Affect Pre-service Teacher Candidates’ Self-Efficacy in Teaching Mathematics?,

This study is related to a previous study (Ribeiro, 2009) that examined teachers’ perceptions of teaching self-efficacy. In the first study the sample consisted of two groups of teachers that took the same professional development course in mathematics. The comparison group took the course in their school district with other teachers and the experimental group took the course with pre-service teachers in a university classroom. After completing the course, both groups were measured in three dimensions of teaching self-efficacy: student engagement, instructional strategies, and classroom climate. Findings indicated that although both groups had significant gains in self-efficacy toward teaching mathematics in the three dimensions, there was not a significant difference between the adjusted post-test group means. The study presented in this paper also examines perceptions of self-efficacy in the dimensions of student engagement, instructional strategies, and classroom climate, however, the focus is on the pre-service teachers who were part of the original study

Evaluating humidity recovery efficiency of currently available heat and moisture exchangers: a respiratory system model study

OBJECTIVES: To evaluate and compare the efficiency of humidification in available heat and moisture exchanger models under conditions of varying tidal volume, respiratory rate, and flow rate. INTRODUCTION: Inspired gases are routinely preconditioned by heat and moisture exchangers to provide a heat and water content similar to that provided normally by the nose and upper airways. The absolute humidity of air retrieved from and returned to the ventilated patient is an important measurable outcome of the heat and moisture exchangers' humidifying performance. METHODS: Eight different heat and moisture exchangers were studied using a respiratory system analog. The system included a heated chamber (acrylic glass, maintained at 37°C), a preserved swine lung, a hygrometer, circuitry and a ventilator. Humidity and temperature levels were measured using eight distinct interposed heat and moisture exchangers given different tidal volumes, respiratory frequencies and flow-rate conditions. Recovery of absolute humidity (%RAH) was calculated for each setting. RESULTS: Increasing tidal volumes led to a reduction in %RAH for all heat and moisture exchangers while no significant effect was demonstrated in the context of varying respiratory rate or inspiratory flow. CONCLUSIONS: Our data indicate that heat and moisture exchangers are more efficient when used with low tidal volume ventilation. The roles of flow and respiratory rate were of lesser importance, suggesting that their adjustment has a less significant effect on the performance of heat and moisture exchangers

Composition and temporal patterns of larval fish communities in Chesapeake and Delaware Bays, USA

Comparing larval fish assemblages in different estuaries provides insights about the coastal distribution of larval populations, larval transport, and adult spawning locations. We simultaneously compared the larval fish assemblages entering 2 Middle Atlantic Bight (MAB) estuaries(Delaware Bay and Chesapeake Bay, USA) through weekly sampling from 2007 to 2009. In total,43 taxa (32 families) and 36 taxa (24 families) were collected in Delaware and Chesapeake Bays,respectively. Mean taxonomic diversity, mean richness, and evenness were generally lower in Delaware Bay. Communities of both bays were dominated by Anchoaspp., Gobiosomaspp.,Micropogonias undulatus, and Brevoortia tyrannus; Paralichthys spp. was more abundant in Delaware Bay and Microgobius thalassinus was more abundant in Chesapeake Bay. Inter-annual variation in the larval fish communities was low at both sites, with a relatively consistent composition across years, but strong seasonal (intra-annual) variation in species composition occurred in both bays. Two groups were identified in Chesapeake Bay: a ‘winter’ group dominated by shelf-spawned species and a ‘summer’ group comprising obligate estuarine species and coastal species.In Delaware Bay, 4 groups were identified: a ‘summer’ group of mainly obligate estuarine fishes being replaced by a ‘fall’ group; ‘winter’ and ‘spring’ groups were dominated by shelf-spawned and obligate estuarine species, respectively. This study demonstrates that inexpensive and simultaneous sampling in different estuaries provides important insights into the variability in community structure of fish assemblages at large spatial scales

Genetic Variability in CLU and Its Association with Alzheimer's Disease

Background: Recently, two large genome wide association studies in Alzheimer disease (AD) have identified variants in three different genes (CLU, PICALM and CR1) as being associated with the risk of developing AD. The strongest association was reported for an intronic single nucleotide polymorphism (SNP) in CLU.Methodology/Principal Findings: To further characterize this association we have sequenced the coding region of this gene in a total of 495 AD cases and 330 healthy controls. A total of twenty-four variants were found in both cases and controls. For the changes found in more than one individual, the genotypic frequencies were compared between cases and controls. Coding variants were found in both groups (including a nonsense mutation in a healthy subject), indicating that the pathogenicity of variants found in this gene must be carefully evaluated. We found no common coding variant associated with disease. In order to determine if common variants at the CLU locus effect expression of nearby (cis) mRNA transcripts, an expression quantitative loci (eQTL) analysis was performed. No significant eQTL associations were observed for the SNPs previously associated with AD.Conclusions/Significance: We conclude that common coding variability at this locus does not explain the association, and that there is no large effect of common genetic variability on expression in brain tissue. We surmise that the most likely mechanism underpinning the association is either small effects of genetic variability on resting gene expression, or effects on damage induced expression of the protein

The transcriptome of the salivary glands of the female western black-legged tick \u3cem\u3eIxodes pacificus\u3c/em\u3e (Acari: Ixodidae)

Sequencing of an Ixodes pacificus salivary gland cDNA library yielded 1068 sequences with an average undetermined nucleotide of 1.9% and an average length of 487 base pairs. Assembly of the expressed sequence tags yielded 557 contigs, 138 of which appear to code for secreted peptides or proteins based on translation of a putative signal peptide. Based on the BLASTX similarity of these contigs to 66 matches of Ixodes scapularis peptide sequences, only 58% sequence identity was found, indicating a rapid divergence of salivary proteins as observed previously for mosquito and triatomine bug salivary proteins. Here we report 106 mostly full-length sequences that clustered in 16 different families: Basic-tail proteins rich in lysine in the carboxy-terminal, Kunitz-containing proteins (monolaris, ixolaris and penthalaris families), proline-rich peptides, 5-, 9.4- and 18.7-kDa proteins of unknown functions, in addition to metalloproteases (class PIII-like) similar to reprolysins. We also have found a family of disintegrins, named ixodegrins that display homology to variabilin, a GPIIb/IIIa antagonist from the tick Dermacentor variabilis. In addition, we describe peptides (here named ixostatins) that display remarkable similarities to the cysteine-rich domain of ADAMST-4 (aggrecanase). Many molecules were assigned in the lipocalin family (histamine-binding proteins); others appear to be involved in oxidant metabolism, and still others were similar to ixodid proteins such as the anticomplement ISAC. We also identified for the first time a neuropeptide-like protein (nlp-31) with GGY repeats that may have antimicrobial activity. In addition, 16 novel proteins without significant similarities to other tick proteins and 37 housekeeping proteins that may be useful for phylogenetic studies are described. Some of these proteins may be useful for studying vascular biology or the immune system, for vaccine development, or as immunoreagents to detect prior exposure to ticks

Dead or alive: sediment DNA archives as tools for tracking aquatic evolution and adaptation

DNA can be preserved in marine and freshwater sediments both in bulk sediment and in intact, viable resting stages. Here, we assess the potential for combined use of ancient, environmental, DNA and timeseries of resurrected long-term dormant organisms, to reconstruct trophic interactions and evolutionary adaptation to changing environments. These new methods, coupled with independent evidence of biotic and abiotic forcing factors, can provide a holistic view of past ecosystems beyond that offered by standard palaeoecology, help us assess implications of ecological and molecular change for contemporary ecosystem functioning and services, and improve our ability to predict adaptation to environmental stress

Toxicological in vivo studies of an oral insulin nanosystem

http://www.sciencedirect.com/science/article/B6TCR-4PKH640-7G/1/31df064ec957f50aa568d739cd5d741

T-Cell Memory Responses Elicited by Yellow Fever Vaccine are Targeted to Overlapping Epitopes Containing Multiple HLA-I and -II Binding Motifs

The yellow fever vaccines (YF-17D-204 and 17DD) are considered to be among the safest vaccines and the presence of neutralizing antibodies is correlated with protection, although other immune effector mechanisms are known to be involved. T-cell responses are known to play an important role modulating antibody production and the killing of infected cells. However, little is known about the repertoire of T-cell responses elicited by the YF-17DD vaccine in humans. In this report, a library of 653 partially overlapping 15-mer peptides covering the envelope (Env) and nonstructural (NS) proteins 1 to 5 of the vaccine was utilized to perform a comprehensive analysis of the virus-specific CD4+ and CD8+ T-cell responses. The T-cell responses were screened ex-vivo by IFN-γ ELISPOT assays using blood samples from 220 YF-17DD vaccinees collected two months to four years after immunization. Each peptide was tested in 75 to 208 separate individuals of the cohort. The screening identified sixteen immunodominant antigens that elicited activation of circulating memory T-cells in 10% to 33% of the individuals. Biochemical in-vitro binding assays and immunogenetic and immunogenicity studies indicated that each of the sixteen immunogenic 15-mer peptides contained two or more partially overlapping epitopes that could bind with high affinity to molecules of different HLAs. The prevalence of the immunogenicity of a peptide in the cohort was correlated with the diversity of HLA-II alleles that they could bind. These findings suggest that overlapping of HLA binding motifs within a peptide enhances its T-cell immunogenicity and the prevalence of the response in the population. In summary, the results suggests that in addition to factors of the innate immunity, "promiscuous" T-cell antigens might contribute to the high efficacy of the yellow fever vaccines. © 2013 de Melo et al

Short-chain di-ureasil ormolytes doped with potassium triflate: Phase diagram and conductivity behavior

Di-urea cross-linked poly(oxyethylene)/siloxane hybrids, synthesized by the sol-gel process and containing a wide concentration range of potassium triflate, KCF3SO3, have been analyzed by x-ray diffraction and differential scanning calorimetry. The pseudo-phase diagram proposed has been taken into account in the interpretation of the complex impedance measurements. The xerogels prepared are obtained as transparent, thin monoliths . At room temperature the highest conductivity found was 2 x 10-6Scm-1.Fundação para a Ciência e a Tecnologia (FCT