65 research outputs found
Reading Remediation Program for Struggling Readers: An Impact Study
One of the most important aspects of education is reading, which is essential to progress in a literate
society. It is important then to speed up reading through reading programs. Reading remediation is a
supplemental reading program that focuses on correct phonological processes. The study established
the value of reading remediation as a tool for helping struggling readers in grade 2 to learn more
effectively. In particular, it sought to ascertain how the program had affected a child's reading ability
before and after its implementation. The experimental pretest-posttest research design was used for
this investigation. Microsoft Excel was utilized to simplify the statistical computation of the data.
Results showed that the respondents' performance ratings in the pretest were poor, but they were
good in the post-test, indicating that there is an improvement in performance after giving struggling
readers reading remediation. Therefore, the Reading Remediation is a useful tool for improving
learning for the struggling grade 2 readers of Sevilla Elementary School
Comparative susceptibility of \u3ci\u3eOstrinia furnacalis, Ostrinia nubilalis,\u3c/i\u3e and \u3ci\u3eDiatraea saccharalis\u3c/i\u3e (Lepidoptera: Crambidae) to \u3ci\u3eBacillus thuringiensis\u3c/i\u3e Cry1 toxins
Transgenic corn hybrids that express toxins from Bacillus thuringiensis (Bt) are highly effective against the European corn borer, Ostrinia nubilalis (HΓΌbner), and the closely related Asian corn borer, Ostrinia furnacalis (GuenΓ©e). Since the registration of Bt corn hybrids in the U.S. in 1996, there has been a great deal of information generated on O. nubilalis. However, relatively little information exists for O. furnacalis. To help determine whether the information generated for O. nubilalis can be leveraged for decisions regarding the use of transgenic Bt corn against O. furnacalis, experiments were designed to determine whether the pattern of sensitivity to various Bt Cry1 toxins is similar between the two species. Test insects included laboratory-reared O. furnacalis originating from Malaysia, a Bt-susceptible laboratory colony of O. nubilalis maintained at the University of Nebraska-Lincoln (UNL) and an out-group consisting of the sugarcane borer, Diatraea saccharalis (F.), from Louisiana which represents a different genus from the same family. O. furnacalis and O. nubilalis exhibited a similar pattern of susceptibility to all the Cry1 toxins and were highly susceptible to the range of Bt toxins tested including Cry1Aa, Cry1Ab, Cry1Ac and Cry1F. Both of the Ostrinia species were more tolerant to Cry1Ba compared with D. saccharalis, although sensitivity of O. furnacalis was intermediate and did not differ significantly from that of O. nubilalis and D. saccharalis. D. saccharalis was also susceptible to the range of toxins tested but unlike the two Ostrinia species, was more tolerant to Cry1F and more susceptible to Cry1Ba. These results indicate that both of the Ostrinia corn borer species are similar in sensitivity to the Cry1Aa, Cry1Ab, Cry1Ac, Cry1Ba and Cry1F toxins, thus suggesting shared toxin receptors and mechanisms of toxicity for the two species
Seagrass Canopy Photosynthetic Response Is a Function of Canopy Density and Light Environment: A Model for Amphibolis griffithii
A three-dimensional computer model of canopies of the seagrass Amphibolis griffithii was used to investigate the consequences of variations in canopy structure and benthic light environment on leaf-level photosynthetic saturation state. The model was constructed using empirical data of plant morphometrics from a previously conducted shading experiment and validated well to in-situ data on light attenuation in canopies of different densities. Using published values of the leaf-level saturating irradiance for photosynthesis, results show that the interaction of canopy density and canopy-scale photosynthetic response is complex and non-linear, due to the combination of self-shading and the non-linearity of photosynthesis versus irradiance (P-I) curves near saturating irradiance. Therefore studies of light limitation in seagrasses should consider variation in canopy structure and density. Based on empirical work, we propose a number of possible measures for canopy scale photosynthetic response that can be plotted to yield isoclines in the space of canopy density and light environment. These plots can be used to interpret the significance of canopy changes induced as a response to decreases in the benthic light environment: in some cases canopy thinning can lead to an equivalent leaf level light environment, in others physiological changes may also be required but these alone may be inadequate for canopy survival. By providing insight to these processes the methods developed here could be a valuable management tool for seagrass conservation during dredging or other coastal developments
Photoacclimation strategies in northeastern Atlantic seagrasses: Integrating responses across plant organizational levels
Seagrasses live in highly variable light environments and adjust to these variations by expressing acclimatory responses at different plant organizational levels (meadow, shoot, leaf and chloroplast level). Yet, comparative studies, to identify species' strategies, and integration of the relative importance of photoacclimatory adjustments at different levels are still missing. The variation in photoacclimatory responses at the chloroplast and leaf level were studied along individual leaves of Cymodocea nodosa, Zostera marina and Z. noltei, including measurements of variable chlorophyll fluorescence, photosynthesis, photoprotective capacities, non-photochemical quenching and D1-protein repair, and assessments of variation in leaf anatomy and chloroplast distribution. Our results show that the slower-growing C. nodosa expressed rather limited physiological and biochemical adjustments in response to light availability, while both species of faster-growing Zostera showed high variability along the leaves. In contrast, the inverse pattern was found for leaf anatomical adjustments in response to light availability, which were more pronounced in C. nodosa. This integrative plant organizational level approach shows that seagrasses differ in their photoacclimatory strategies and that these are linked to the species' life history strategies, information that will be critical for predicting the responses of seagrasses to disturbances and to accordingly develop adequate management strategies.Fundacao para a Ciencia e Tecnologia (FCT), Portugal [PTDC/MAR-EST/4257/2014
Inhibition of HERG1 K+ channel protein expression decreases cell proliferation of human small cell lung cancer cells
HERG (human ether-Γ -go-go-related gene) K+ currents fulfill important ionic functions in cardiac and other excitable cells. In addition, HERG channels influence cell growth and migration in various types of tumor cells. The mechanisms underlying these functions are still not resolved. Here, we investigated the role of HERG channels for cell growth in a cell line (SW2) derived from small cell lung cancer (SCLC), a malignant variant of lung cancer. The two HERG1 isoforms (HERG1a, HERG1b) as well as HERG2 and HERG3 are expressed in SW2 cells. Inhibition of HERG currents by acute or sustained application of E-4031, a specific ERG channel blocker, depolarized SW2 cells by 10β15Β mV. This result indicated that HERG K+ conductance contributes considerably to the maintenance of the resting potential of about β45Β mV. Blockage of HERG channels by E-4031 for up to 72Β h did not affect cell proliferation. In contrast, siRNA-induced inhibition of HERG1 protein expression decreased cell proliferation by about 50%. Reduction of HERG1 protein expression was confirmed by Western blots. HERG current was almost absent in SW2 cells transfected with siRNA against HERG1. Qualitatively similar results were obtained in three other SCLC cell lines (OH1, OH3, H82), suggesting that the HERG1 channel protein is involved in SCLC cell growth, whereas the ion-conducting function of HERG1 seems not to be important for cell growth
Contribution of Intrinsic Reactivity of the HIV-1 Envelope Glycoproteins to CD4-Independent Infection and Global Inhibitor Sensitivity
Human immunodeficiency virus (HIV-1) enters cells following sequential activation of the high-potential-energy viral envelope glycoprotein trimer by target cell CD4 and coreceptor. HIV-1 variants differ in their requirements for CD4; viruses that can infect coreceptor-expressing cells that lack CD4 have been generated in the laboratory. These CD4-independent HIV-1 variants are sensitive to neutralization by multiple antibodies that recognize different envelope glycoprotein epitopes. The mechanisms underlying CD4 independence, global sensitivity to neutralization and the association between them are still unclear. By studying HIV-1 variants that differ in requirements for CD4, we investigated the contribution of CD4 binding to virus entry. CD4 engagement exposes the coreceptor-binding site and increases the βintrinsic reactivityβ of the envelope glycoproteins; intrinsic reactivity describes the propensity of the envelope glycoproteins to negotiate transitions to lower-energy states upon stimulation. Coreceptor-binding site exposure and increased intrinsic reactivity promote formation/exposure of the HR1 coiled coil on the gp41 transmembrane glycoprotein and allow virus entry upon coreceptor binding. Intrinsic reactivity also dictates the global sensitivity of HIV-1 to perturbations such as exposure to cold and the binding of antibodies and small molecules. Accordingly, CD4 independence of HIV-1 was accompanied by increased susceptibility to inactivation by these factors. We investigated the role of intrinsic reactivity in determining the sensitivity of primary HIV-1 isolates to inhibition. Relative to the more common neutralization-resistant (βTier 2-likeβ) viruses, globally sensitive (βTier 1β) viruses exhibited increased intrinsic reactivity, i.e., were inactivated more efficiently by cold exposure or by a given level of antibody binding to the envelope glycoprotein trimer. Virus sensitivity to neutralization was dictated both by the efficiency of inhibitor/antibody binding to the envelope glycoprotein trimer and by envelope glycoprotein reactivity to the inhibitor/antibody binding event. Quantitative differences in intrinsic reactivity contribute to HIV-1 strain variability in global susceptibility to neutralization and explain the long-observed relationship between increased inhibitor sensitivity and decreased entry requirements for target cell CD4
Computational screening of functional monomers for bitertanol sensing using molecularly imprinted polymer
Low-Cost DIY Capacitive Sensor for Water Activity of Food Samples
Water activity of food products has been proven to be an important indicator in establishing food quality, mainly ensuring stability and safety. However, most commercial water activity meters are expensive and relatively inaccessible for micro-, small-and medium-sized enterprises (MSMEs). Thus, this study utilizes an off-the-shelf commercial relative humidity (RH) meter with a capacitive sensor that is relatively inexpensive and retrofitted it with 3D -printed casing and sample container to allow measurement of the equilibrium RH of a food sample. This is then calibrated to yield the water activity at room temperature (ca. 25C). The RH sensor shows a linear response to salt solution calibration standards and a sensitivity that can be corrected; the relative mean square error is Β± 0.03. The calibrated DIY RH sensor was then tested for measurement of water activity of various food samples, wet and dry, with aw in the range of 0.20 to 0.90. Comparison of the results from the DIY RH sensor versus those of an analytical water activity meter (with a dew-point sensor) shows that the margin of error is Β± 0.05. This would be good enough for estimating the water activity of food products especially for those that need to establish a cutoff for food safety of aw \u3c 0.60. The DIY RH water activity sensor is also portable and will be a useful tool for point-of-use scenarios (such as in solar drying of food) and in resource-limited settings
Design and implementation of a PC interfaceable module for acquiring EMG, BVP, GSR and respiration signals
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