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Mobile Technology in Science Classrooms: Using iPad-enabled Constructivist Learning to Promote Collaborative Problem Solving and Chemistry Learning
Most recently, there has been a noticeable rise in the push for use of technology in the classroom. The advancement in digital science has increased greatly the capacity to explore animations, models, and interesting apps. that should substantially enhance science cognition. At the same time, there is a great need to increase collaboration in the science classroom. There is a concern that the collaborative experience will be lost with the use of technology in the classroom. This study seeks to explore the use of iPads in conjunction with a constructivist learning approach to promote student collaboration. The participants in this study included two sections of 11th grade AP Chemistry students. Data was generated from different sources such as teacher observations of classroom interactions patterned after Gilles (2004). In order to gauge student perception of working in groups with the use of the iPad, survey questions adapted from Knezek, Mills and Wakefield (2012) and group interviews were used (Galleta, 2013). Learning outcomes were assessed using methods adapted from a study by Lord and Baviskar (2007). Findings of this study showed high percentages of evidence for increased community, productive student group communication, effective feedback through use of the iPads, and value of the interactive apps., but it also showed that students still preferred face-to-face interactions over virtual interactions for certain learning situations. The study showed good content learning outcomes, as well as favorable opinions among the students for the effectiveness of the use of iPads in collaborative settings in the classroom
Comparison of Emergency Medical Services Delivery Performance using Maximal Covering Location and Gradual Cover Location Problems
Ambulance location is one of the critical factors that determine the efficiency of emergency medical services delivery. Maximal Covering Location Problem is one of the widely used ambulance location models. However, its coverage function is considered unrealistic because of its ability to abruptly change from fully covered to uncovered. On the contrary, Gradual Cover Location Problem coverage is considered more realistic compared to Maximal Cover Location Problem because the coverage decreases over distance. This paper examines the delivery of Emergency Medical Services under the models of Maximal Covering Location Problem and Gradual Cover Location Problem. The results show that the latter model is superior, especially when the Maximal Covering Location Problem has been deemed fully covered
Detector Control System for the Electromagnetic Calorimeter of the CMS experiment
The Compact Muon Solenoid (CMS) is one of the general purpose particle detectors at the Large Hadron Collider (LHC) at CERN. The challenging constraints on the design of one of its sub-detectors, the Electromagnetic Calorimeter (ECAL), required the development of a complex Detector Control System (DCS). In this paper the general features of the CMS ECAL DCS during the period of commissioning and cosmic running will be presented. The feedback from the people involved was used for several upgrades of the system in order to achieve a robust, flexible and stable control system. A description of the newly implemented features for the CMS ECAL DCS subsystems will be given as well
Analysis of Signaling Mechanisms Regulating Microglial Process Movement
Microglia, the brainâs innate immune cells, are extremely motile cells, continuously
surveying the CNS to serve homeostatic functions and to respond to pathological events. In the
healthy brain, microglia exhibit a small cell body with long, branched and highly motile
processes, which constantly extend and retract, effectively âpatrollingâ the brain parenchyma.
Over the last decade, methodological advances in microscopy and the availability of
genetically encoded reporter mice have allowed us to probe microglial physiology in situ.
Beyond their classical immunological roles, unexpected functions of microglia have been
revealed, both in the developing and the adult brain: microglia regulate the generation of
newborn neurons, control the formation and elimination of synapses, and modulate neuronal
activity. Many of these newly ascribed functions depend directly on microglial process
movement. Thus, elucidating the mechanisms underlying microglial motility is of great
importance to understand their role in brain physiology and pathophysiology. Two-photon
imaging of fluorescently labelled microglia, either in vivo or ex vivo in acute brain slices, has
emerged as an indispensable tool for investigating microglial movements and their functional
consequences. This chapter aims to provide a detailed description of the experimental data
acquisition and analysis needed to address these questions, with a special focus on key dynamic
and morphological metrics such as surveillance, directed motility and ramification
bantam Is Required for Optic Lobe Development and Glial Cell Proliferation
microRNAs (miRNAs) are small, conserved, non-coding RNAs that contribute to the control of many different cellular processes, including cell fate specification and growth control. Drosophila bantam, a conserved miRNA, is involved in several functions, such as stimulating proliferation and inhibiting apoptosis in the wing disc. Here, we reported the detailed expression pattern of bantam in the developing optic lobe, and demonstrated a new, essential role in promoting proliferation of mitotic cells in the optic lobe, including stem cells and differentiated glial cells. Changes in bantam levels autonomously affected glial cell number and distribution, and non-autonomously affected photoreceptor neuron axon projection patterns. Furthermore, we showed that bantam promotes the proliferation of mitotically active glial cells and affects their distribution, largely through down regulation of the T-box transcription factor, optomotor-blind (omb, Flybase, bifid). Expression of omb can rescue the bantam phenotype, and restore the normal glial cell number and proper glial cell positioning in most Drosophila brains. These results suggest that bantam is critical for maintaining the stem cell pools in the outer proliferation center and glial precursor cell regions of the optic lobe, and that its expression in glial cells is crucial for their proliferation and distribution
Unlocking preservation bias in the amber insect fossil record through experimental decay.
Fossils entombed in amber are a unique resource for reconstructing forest ecosystems, and resolving relationships of modern taxa. Such fossils are famous for their perfect, life-like appearance. However, preservation quality is vast with many sites showing only cuticular preservation, or no fossils. The taphonomic processes that control this range are largely unknown; as such, we know little about potential bias in this important record. Here we employ actualistic experiments, using, fruit flies and modern tree resin to determine whether resin type, gut microbiota, and dehydration prior to entombment affects decay. We used solid phase microextraction gas chromatography-mass spectrometry (SPME GC-MS) to confirm distinct tree resin chemistry; gut microbiota of flies was modified using antibiotics and categorized though sequencing. Decay was assessed using phase contrast synchrotron tomography. Resin type demonstrates a significant control on decay rate. The composition of the gut microbiota was also influential, with minor changes in composition affecting decay rate. Dehydration prior to entombment, contrary to expectations, enhanced decay. Our analyses show that there is potential significant bias in the amber fossil record, especially between sites with different resin types where ecological completeness and preservational fidelity are likely affected
Roadmap on spatiotemporal light fields
Spatiotemporal sculpturing of light pulse with ultimately sophisticated
structures represents the holy grail of the human everlasting pursue of
ultrafast information transmission and processing as well as ultra-intense
energy concentration and extraction. It also holds the key to unlock new
extraordinary fundamental physical effects. Traditionally, spatiotemporal light
pulses are always treated as spatiotemporally separable wave packet as solution
of the Maxwell's equations. In the past decade, however, more generalized forms
of spatiotemporally nonseparable solution started to emerge with growing
importance for their striking physical effects. This roadmap intends to
highlight the recent advances in the creation and control of increasingly
complex spatiotemporally sculptured pulses, from spatiotemporally separable to
complex nonseparable states, with diverse geometric and topological structures,
presenting a bird's eye viewpoint on the zoology of spatiotemporal light fields
and the outlook of future trends and open challenges.Comment: This is the version of the article before peer review or editing, as
submitted by an author to Journal of Optics. IOP Publishing Ltd is not
responsible for any errors or omissions in this version of the manuscript or
any version derived from i
Genome-wide analysis reveals the extent of EAV-HP integration in domestic chicken
Background: EAV-HP is an ancient retrovirus pre-dating Gallus speciation, which continues to circulate in modern chicken populations, and led to the emergence of avian leukosis virus subgroup J causing significant economic losses to the poultry industry. We mapped EAV-HP integration sites in Ethiopian village chickens, a Silkie, Taiwan Country chicken, red junglefowl Gallusgallus and several inbred experimental lines using whole-genome sequence data.
Results: An average of 75.22 ± 9.52 integration sites per bird were identified, which collectively group into 279 intervals of which 5% are common to 90% of the genomes analysed and are suggestive of pre-domestication integration events. More than a third of intervals are specific to individual genomes, supporting active circulation of EAV-HP in modern chickens. Interval density is correlated with chromosome length (P<2.31â6), and 27 % of intervals are located within 5 kb of a transcript. Functional annotation clustering of genes reveals enrichment for immune-related functions (P<0.05).
Conclusions: Our results illustrate a non-random distribution of EAV-HP in the genome, emphasising the importance it may have played in the adaptation of the species, and provide a platform from which to extend investigations on the co-evolutionary significance of endogenous retroviral genera with their hosts
Phenotypic Switching of Nonpeptidergic Cutaneous Sensory Neurons following Peripheral Nerve Injury
In adult mammals, the phenotype of half of all pain-sensing (nociceptive) sensory neurons is tonically modulated by growth factors in the glial cell line-derived neurotrophic factor (GDNF) family that includes GDNF, artemin (ARTN) and neurturin (NRTN). Each family member binds a distinct GFRα family co-receptor, such that GDNF, NRTN and ARTN bind GFRα1, -α2, and -α3, respectively. Previous studies revealed transcriptional regulation of all three receptors in following axotomy, possibly in response to changes in growth factor availability. Here, we examined changes in the expression of GFRα1-3 in response to injury in vivo and in vitro. We found that after dissociation of adult sensory ganglia, up to 27% of neurons die within 4 days (d) in culture and this can be prevented by nerve growth factor (NGF), GDNF and ARTN, but not NRTN. Moreover, up-regulation of ATF3 (a marker of neuronal injury) in vitro could be prevented by NGF and ARTN, but not by GDNF or NRTN. The lack of NRTN efficacy was correlated with rapid and near-complete loss of GFRα2 immunoreactivity. By retrogradely-labeling cutaneous afferents in vivo prior to nerve cut, we demonstrated that GFRα2-positive neurons switch phenotype following injury and begin to express GFRα3 as well as the capsaicin receptor, transient receptor potential vanilloid 1(TRPV1), an important transducer of noxious stimuli. This switch was correlated with down-regulation of Runt-related transcription factor 1 (Runx1), a transcription factor that controls expression of GFRα2 and TRPV1 during development. These studies show that NRTN-responsive neurons are unique with respect to their plasticity and response to injury, and suggest that Runx1 plays an ongoing modulatory role in the adult
Are movement disorders and sensorimotor injuries pathologic synergies? When normal multi-joint movement synergies become pathologic
The intact nervous system has an exquisite ability to modulate the activity of multiple muscles acting at one or more joints to produce an enormous range of actions. Seemingly simple tasks, such as reaching for an object or walking, in fact rely on very complex spatial and temporal patterns of muscle activations. Neurological disorders such as stroke and focal dystonia affect the ability to coordinate multi-joint movements. This article reviews the state of the art of research of muscle synergies in the intact and damaged nervous system, their implications for recovery and rehabilitation, and proposes avenues for research aimed at restoring the nervous systemâs ability to control movement
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