Identification of metrics used by decision makers to determine the efficacy of wireless communication systems in higher education

This research described the wireless network technologies that are available for use in higher education, determined the categories of metrics used to evaluate wireless network efficacy, and yielded a self-assessment instrument for guiding small college administrators considering wireless local area network systems.;The features and benefits of contemporary wireless systems in higher education were identified through a review of the professional journals, government publications, and standards industry documentation. The literature identified three categories of metrics beneficial for the evaluation of efficacy of wireless campus local area networks: cost, speed, and reliability. After identification of these categories of metrics, a modified Delphi technique was administered to ten wireless network experts in higher education. The expert group was made up of seven higher education wireless decision makers and three wireless industry professionals.;The wireless experts responded to Instrument One which identified 27 metrics in the three categories of metrics. The experts generated 19 essential metrics: four in the category of cost, seven in the category of speed, and eight in the category of reliability. Eight supplemental metrics were also identified in Instrument One: four in the category of cost, two in the category of speed, and two in the category of reliability.;Instrument Two generated 27 questions that could guide wireless decision makers in higher education. These metrics offer a timeless guide to wireless system planning on small college campuses. The self-assessment instrument will assist in gathering information specific to the small college environment, and in gathering current specifications for wireless network systems. The analysis of information gained from the use of this tool will help wireless campus networks to operate as an integrated part of teaching and learning

How age of bilingual exposure can change the neural systems for language in the developing brain: A functional near infrared spectroscopy investigation of syntactic processing in monolingual and bilingual children

AbstractIs the developing bilingual brain fundamentally similar to the monolingual brain (e.g., neural resources supporting language and cognition)? Or, does early-life bilingual language experience change the brain? If so, how does age of first bilingual exposure impact neural activation for language?We compared how typically-developing bilingual and monolingual children (ages 7–10) and adults recruit brain areas during sentence processing using functional Near Infrared Spectroscopy (fNIRS) brain imaging. Bilingual participants included early-exposed (bilingual exposure from birth) and later-exposed individuals (bilingual exposure between ages 4–6).Both bilingual children and adults showed greater neural activation in left-hemisphere classic language areas, and additionally, right-hemisphere homologues (Right Superior Temporal Gyrus, Right Inferior Frontal Gyrus). However, important differences were observed between early-exposed and later-exposed bilinguals in their earliest-exposed language. Early bilingual exposure imparts fundamental changes to classic language areas instead of alterations to brain regions governing higher cognitive executive functions. However, age of first bilingual exposure does matter. Later-exposed bilinguals showed greater recruitment of the prefrontal cortex relative to early-exposed bilinguals and monolinguals.The findings provide fascinating insight into the neural resources that facilitate bilingual language use and are discussed in terms of how early-life language experiences can modify the neural systems underlying human language processing

Novel mesoscale defect structure on NiO(1 0 0) surfaces by atomic force microscopy

Cleaved NiO(1 0 0) surfaces were imaged with atomic force microscopy (AFM) to determine defect concentrations and morphology. Random (0 1 0) and (0 0 1) oriented steps, which have been previously characterized, were the most common defect observed on the cleaved surface and formed with step heights in multiples of 2.1 Å, the Ni–O nearest-neighbor distance, and terrace widths in the range of 25–100 nm. In addition, the surface showed novel mesoscale (~0.5–2 μm) square pyramidal defects with the pyramid base oriented along (1 0 0) symmetry related directions. Upon etching, the pyramidal defects converted to more stable cubic pits, consistent with (1 0 0) symmetry related walls. The square pyramidal pits tended to cluster or to form along step edges, where the weakened structure is more susceptible to surface deformations. Also, a small concentration of square pyramidal pits, oriented with the base of the pyramid along (0 1 1), was observed on the cleaved NiO surfaces. For comparison purposes, chemical mechanical polished (CMP) NiO(1 0 0) substrates were imaged with AFM. Defect concentrations were of comparable levels to the cleaved surface, but showed a different distribution of defect types. Long-ranged stepped defects were much less common on CMP substrates, and the predominant defects observed were cubic pits with sidewalls steeper than could be accurately measured by the AFM tip. These defects were similar in size and structure to those observed on cleaved NiO(1 0 0) surfaces that had been acid etched, although pit clustering was more pronounced for the CMP surfaces

The mechanisms of latrophilin 1-mediated control of spontaneous exocytosis at the mouse neuromuscular junction

Latrophilin1 (LPHN1) is a presynaptic adhesion G protein-coupled receptor involved in the control of spontaneous exocytosis of neurotransmitters. The effects of LPHN1 activation on exocytosis have been described on several model systems, such as cultured hippocampal neurons and neuromuscular junction (NMJ) using its well known agonist LTXN4C, and include a massive increase in exocytosis characterised by periods of intense release (bursts) interspersed with periods of moderate activity (interburst intervals). However, the molecular mechanisms underlying these effects were yet to be determined. Based on previous observations that LPHN1 is associated to G proteins, and that its activation leads to activation of PLC and increased IP3, we hypothesize that LPHN1 controls exocytosis via the G?q protein pathway, whose activation ultimately results in the release of Ca2+ from IP3-sensitive Ca2+ stores. Using a pharmacological approach and the current clamp method at the mouse NMJ, we first used LPHN1 KO preparations to study the role of LPHN1 on spontaneous exocytosis in resting conditions, and to show that LPHN1 is the only receptor mediating the effects observed upon stimulation by LTXN4C. Then, we interfered with several molecules involved in the G?q pathway to test their involvement in LPHN1 activation, and we investigated the role of store-operated (SOCCs) and voltage-gated (VGCCs) Ca2+ channels in mediating the Ca2+ influx that is necessary for the development of LPHN1 effects. Our results support the hypothesis LPHN1 is involved in the regulation of spontaneous exocytosis at rest and that it is the receptor mediating the increased exocytosis following stimulation by LTXN4C; the suggestions that G?q and its intracellular pathway mediate the effects of LPHN1 activation on spontaneous exocytosis, and that SOCCs and VGCCs (particularly Cav2.1) mediate the Ca2+ influx necessary for the development of LPHN1 effects are also supported by our findings. Altogether, this work uncovered the mechanisms by which G protein-coupled receptors, in this case LPHN1, can regulate the rate of spontaneous neurotransmitter release at the mouse NMJ

Water buffalo mozzarella cheese stored in polysaccharide-based gels: correlation between prolongation of the shelf-life and physicochemical parameters.

An innovative packaging system has been developed, based on natural gels, that has shown the peculiar characteristic to strongly increase the shelf life of water buffalo Mozzarella cheese. To explain the mechanism of action of the gel, measurements of Ca and Na in the cheese and in the storage liquid were carried out, together with pH determination. A correlation has been found between the constant level of Ca and pH in the cheese and the prolongation of nutritional characteristics; in fact, both parameters diminish significantly in the absence of gel. At the same time, the weight of the cheese in gel remained constant for as long as 30 d. Confocal laser microscopy gave direct evidence of the persistent physical structure of proteins and lipids of Mozzarella when stored in gel

Statistical Evaluation of Molecular Contamination During Spacecraft Thermal Vacuum Test

The purpose of this paper is to evaluate the statistical molecular contamination data with a goal to improve spacecraft contamination control. The statistical data was generated in typical thermal vacuum tests at the National Aeronautics and Space Administration, Goddard Space Flight Center (GSFC). The magnitude of material outgassing was measured using a Quartz Crystal Microbalance (QCNO device during the test. A solvent rinse sample was taken at the conclusion of each test. Then detailed qualitative and quantitative measurements were obtained through chemical analyses. All data used in this study encompassed numerous spacecraft tests in recent years