Digital Connections: Student Experiences in Online Language Exchanges

Exciting advances in technology have provided foreign language teachers with opportunities to connect students to native speakers of target languages. Much of the research in this area focuses on changes in proficiency or cultural sensitivity. Although valuable, the research is lacking in understanding students’ experiences online, including positive and negative feelings, challenges, as well as students’ overall opinions of the exchanges’ usefulness for learning. The present study used a mixed methods approach to examine the experiences of third-semester university students participating in online language exchanges with native speakers. A third-semester Spanish class at a large university consisting of 18 students was selected as a sample. Students were required to speak online with native Spanish speakers in the target language for 20 minutes each week. Students completed weekly surveys and a final survey, and three students were selected for semi-structured interviews. The data reveal common struggles that students face during online exchanges, methods students use for coping with these difficulties, areas of perceived growth, and social factors that affect students’ experiences. The article concludes with recommendations for what foreign language educators can do to support students in similar online exchanges

Systems and methods for delivering dissolved gases into force-main and gravity sewers

Disclosed are systems and methods for dissolving gases into a fluid that is passing through a force-main and gravity sewer system. The system includes a dissolution tank having a pressure vessel for containing a liquid and for providing a regulated gas head space above the liquid, an inlet that permits passage of wastewater into the gas head space, and an outlet that permits passage of treated wastewater out of the pressure vessel. The system also includes a gas source in communication with the pressure vessel; a pump for supplying wastewater from a force-main or sewer system sump into the pressure vessel under conditions effective to dissolve oxygen gas in the wastewater; and a discharge device in communication with the outlet of the dissolution tank assembly for discharging treated wastewater

A Six-Planet System Around the Star HD 34445

We present a new precision radial velocity dataset that reveals a multi-planet system orbiting the G0V star HD 34445. Our 18-year span consists of 333 precision radial velocity observations, 56 of which were previously published, and 277 which are new data from Keck Observatory, Magellan at Las Campanas Observatory, and the Automated Planet Finder at Lick Observatory. These data indicate the presence of six planet candidates in Keplerian motion about the host star with periods of 1057, 215, 118, 49, 677, and 5700 days, and minimum masses of 0.63, 0.17, 0.1, 0.05, 0.12 and 0.38 Jupiter masses respectively. The HD 34445 planetary system, with its high degree of multiplicity, its long orbital periods, and its induced stellar radial velocity half-amplitudes in the range $2 \,{\rm m\, s^{-1}} \lesssim K \lesssim 5\,{\rm m\, s^{-1}}$ is fundamentally unlike either our own solar system (in which only Jupiter and Saturn induce significant reflex velocities for the Sun), or the Kepler multiple-transiting systems (which tend to have much more compact orbital configurations)Comment: 10 pages, 11 figure

Vacuum UV (VUV) Photo-Oxidation of Polyethersulfone (PES)

International need for water quality is placing a high demand on separation technology to develop advanced oxidative processes for polyethersulfone (PES) membranes to help improve water purification. Therefore, VUV photo-oxidation with a low pressure Ar plasma was studied to improve the hydrophilicity of PES by flowing oxygen over the surface during treatment. X-ray photoelectron spectroscopy (XPS) detected a decrease in the C at% (4.4 ± 1.7 at%), increase in O at% (3.7 ± 1.0 at%), and a constant S at% (5.4 ± 0.2 at%). Curve fitting of the XPS spectra showed a decrease in sp2 C-C aromatic group bonding, and an increase in C-O, C-S, O=C-OH, sulphonate (-SO3 ) and sulphate (-SO4 ) functional groups with treatment time. The water contact angle decreased from 71.9◦ for untreated PES down to a saturation level of 41.9◦ with treatment. Since scanning electron microscopy (SEM) showed no major changes in surface roughness, the increase in hydrophilicity was mainly due to oxidation of the surface. Washing the VUV photo-oxidized PES samples with water or ethanol increased the water contact angle saturation level up to 66◦ indicating the formation of a weak boundary layer

Damage Tolerance Analysis of a Pressurized Liquid Oxygen Tank

A damage tolerance assessment was conducted of an 8,000 gallon pressurized Liquid Oxygen (LOX) tank. The LOX tank is constructed of a stainless steel pressure vessel enclosed by a thermal-insulating vacuum jacket. The vessel is pressurized to 2,250 psi with gaseous nitrogen resulting in both thermal and pressure stresses on the tank wall. Finite element analyses were performed on the tank to characterize the stresses from operation. Engineering material data was found from both the construction of the tank and the technical literature. An initial damage state was assumed based on records of a nondestructive inspection performed on the tank. The damage tolerance analyses were conducted using the NASGRO computer code. This paper contains the assumptions, and justifications, made for the input parameters to the damage tolerance analyses and the results of the damage tolerance analyses with a discussion on the operational safety of the LOX tank

Cold spray deposition of metallic-UHTC composites

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UV Photo-Oxidation of Polybenzimidazole (PBI)

Since polybenzimidazole (PBI) is often used in the aerospace industry and in high temperature fuel cells, this research investigated the surface modification of PBI film with 253.7 and 184.9 nm UV photo-oxidation. As observed by X-ray photoelectron spectroscopy (XPS), the oxygen concentration on the surface increased up to a saturation level of 20.2 ± 0.7 at %. With increasing treatment time, there were significant decreases in the concentrations of C-C sp2 and C=N groups and increases in the concentration of C=O, O-C=O, O-(C=O)-O, C-N, N-O, and N-C=O containing moieties due to 253.7 nm photo-oxidation of the aromatic groups of PBI and reaction with ozone produced by 184. 9 nm photo-dissociation of oxygen. Because no significant changes in surface topography were detected by AFM and SEM measurements, the observed decrease in the water contact angle down to ca. 44°, i.e., increase in hydrophilic, was due to the chemical changes on the surface

Sensory Processing Abnormalities in Community-Dwelling Older Adults with Cognitive Impairment: A Mixed Methods Study

Mild cognitive impairment (MCI) or dementia often leads to behavioral and psychiatric symptoms of dementia (BPSD). Sensory processing abnormalities may be associated with BPSD. The purpose of this study was to explore relationships among sensory processing, behavior, and environmental features within the homes of people with MCI or dementia. This project used mixed methods to assess participants’ sensory processing, care partner perspectives on behaviors, and in situ observations of the home environment. Nine participants with cognitive impairment (MCI n = 8, early dementia = 1) and their care partners were included. Seven participants with cognitive impairment were reported to have abnormal sensory processing. Findings suggest that unique environmental adaptations, tailored to personal and sensory preferences for each participant, were associated with a decreased level of behavioral disruption during the observation periods. Implementing sensory-based approaches to maximize environment adaptation may be beneficial in reducing disruptive behaviors for adults with cognitive impairment