Combining teacher-Led and technology-assisted instruction to improve phoneme blending to read words for elementary students with disabilities

Technology-assisted instruction has potential for helping students improve their reading skills. In the current studies, PowerPoint software was used to supplement teacher-led reading instruction for elementary-aged students with disabilities who struggled with phoneme blending to read words. The effectiveness of the intervention was assessed using two multiple probe design studies across sets of words based on an onset-rime (word family) strategy. In Study 1, teacher-led instruction was paired with technology-assisted instruction for all intervention sessions for three students in first and second grade. In Study 2, teacher-led instruction occurred between baseline and technology-assisted intervention sessions for three students in third and fourth grade. During the initial instruction sessions, participants recorded their own voices onto PowerPoint slides so that their technology-assisted instruction included self-modelling. Results of both studies indicated that technology-assisted instruction can be effective for helping students learn how to blend phonemes to read words; however, performance varied and there were limitations in each study that should be addressed in future research. Relevant implications for classroom instruction are emphasized.     

Bitumen separation for experimental use

A solvent extraction procedure is presented for separating large quantities of bitumen to be used in laboratory experiments. The effectiveness of various solvents is discussed. Data are presented on the properties of extracted bitumen, the unextracted residue and the light ends lost during solvent removal. The effect of bitumen contact with oxygen is also discussed.     

A fluidized bed retort for oil sands

Fluid bed retorting of oil sands is a viable method of extracting oil from mined oil sands. The process is based on a direct heating concept in which one vessel is utilized for the pyrolysis and vaporization of the bitumen contained in the oil sand and for the burning of the residuals which remain with the sand. Experimental results show that a significantly upgraded liquid hydrocarbon product can be obtained. Oil yields can exceed eighty per cent of the bitumen present in the feed material. The sulfur content of the produced oil is reduced. Gas produced can have a significant heating value and contains sulfur mainly in the form of hydrogen sulfide. Refluxing of the overhead product increases liquid yields and reduces the sulfur content of the oil. Water injection and the use of enriched air has a beneficial effect on the process. Thermal efficiencies in excess of eighty per cent can be achieved without recovering the heat from the expended sand.     

Response of direct-seeded guayule to preemergence herbicides

Direct-seeding guayule (Parthenium argentatum Gray) in west Texas has been successful; however, seedlings grow slowly and are extremely susceptible to weed competition. An effective preplant or preemergence herbicide is necessary for establishment. The objective of this study was to examine the effects of preemergence herbicides on guayule stand establishment by direct seeding. Experiments were initiated on a Dalby clay in 1991 and 1992 at the Texas Agricultural Experiment Station Guayule Research Site near Fort Stockton, Texas. Conditioned guayule seed (Mexican Bulk) was planted 10 mm deep on raised beds with a Gaspardo SV255 pneumatic planter at 100 seeds/m. The following herbicides were applied immediately after planting: dimethyl 2,3,5,6-tetrachloro-1,4-benzenedicarboxylate (DCPA) [4.5, 9.0, 11.0 kg ai/ha (hectare)], pendimethalin [N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine] (0.3, 0.6, 1.1 kg/ha) and prodiamine [N³,N³-Di-n-propyl-2,4-dinitro-6-(trifluoromethyl)-m-phenylenediamine] (0.3, 0.6, 1.1 kg/ha). Herbicides were applied in a 0.5-m band on each bed by using a CO₂-powered backpack sprayer with a single-nozzle boom delivering 300 L/ha at 172 kPa pressure. The lowest rates of all herbicides did not significantly reduce guayule stand density in 1991 when compared to the control. DCPA at 9.0 kg/ha was adequately selective in both studies. Guayule stand reduction varied from only 2% with DCPA at 4.5 kg/ha in 1991, to 71% with 1.1 kg/ha of pendimethalin in 1992. DCPA (4.5 and 9.0 kg/ha) would be recommended for preemergence weed control, depending on soil type, when direct seeding guayule. Based on row spacing recommendations for transplants, at least three established seedlings/m would be required for an acceptable guayule stand. Seeding rate could be reduced and still allow for effective preemergence weed control.     

Dufour's gland and its role in secretion of nest cell lining in bees of the genusColletes (Hymenoptera: Colletidae)

The liquid secretion of the Dufour's gland in mated females comprises a mixture of macrocyclic lactones, straight chain mono- and dicarboxylic acids, together with trace amounts of di- and trihydroxy monocarboxylic acids and a series ofn-alkanes. Polymerization of the liquid to form the membranous nest cell lining, which also contains alanine and glutamic acid as major constituents, may be mediated by an enzyme from the thoracic salivary gland and voided via the mouth. The composition and structure of the cell linings are similar to those of Wigglesworth's cuticulin.     

Good Enough is Good Enough: Overcoming Disaster Response Organizations’ Slow Social Media Data Adoption

Organizations that respond to disasters hold unreasonable standards for data arising from technology-enabled citizen contributions. This has strong negative potential for the ability of these responding organizations to incorporate these data into appropriate decision points. We argue that the landscape of the use of social media data in crisis response is varied, with pockets of use and acceptance among organizations. In this paper we present findings from interviews conducted with representatives from large international disaster response organizations concerning their use of social media data in crisis response. We found that emergency responders already operate with less than reliable, or “good enough,” information in offline practice, and that social media data are useful to responders, but only in specific crisis situations. Also, responders do use social media, but only within their known community and extended network. This shows that trust first begins with people and not data. Lastly, we demonstrate the barriers used by responding organizations have gone beyond discussions of trustworthiness and data quality to that of more operational issues.     

Structural characterization of vulcanizates. Part VI. The 2-mercaptobenzothiazole-accelerated natural rubber–sulfur system

The crosslinking efficiency of sulfur in the vulcanization of natural rubber in the presence of 2-mercaptobenzothiazole, zinc oxide, and lauric acid has been determined as a function of cure time, cure temperature, and lauric acid concentration. With a low concentration of lauric acid structurally complex networks are formed, which contain 11–19 combined sulfur atoms per chemical crosslink present. The complexity increases with time of vulcanization. With a high lauric acid concentration much simpler networks are formed, which become progressively more simple as reaction proceeds (6 network-combined sulfur atoms per chemical crosslink, decreasing to 2.4 with time). Increasing the cure temperature from 100 to 140°C. reduces the efficiency of crosslinking in both cases. The changes in efficiency are attributed to the influences of the reaction variables (in particular, the concentration of rubber-soluble complexes of the zinc laurate with zinc benzothiazolyl mercaptide) on the structure and subsequent reactions of initially formed polysulfidic crosslinks.