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Verbal behavior is used when programming instruction for students with Autism to increase language repertoires and motivation to communicate. However, using verbal behavior to provide academic instruction is used less frequently. Reading is defined as the textual operant in Skinner’s 1957 analysis. The skills which lead to textual behavior such as phonological awareness have not received the attention that other non-verbal stimuli have received as an antecedent for evoking tacts. The current research uses ABAB design to determine the effectiveness of using verbal behavior transfer procedures to teach phonological awareness. · Echoic to Tact Transfer provides errorless phonological instruction.· Explicit 1:1 instruction with scheduled reinforcement was used.· Students possessed both an echoic and tact repertoire.· Sessions included target stimuli and previously mastered stimuli for instruction.

Pd–TiO2 catalysts with five Pd loadings were synthesized using a flame aerosol reactor. Studies of the initial and spent catalysts demonstrate that Pd loading impacted the size of Pd sub-nano clusters/nanoparticles and the fraction of Pd (metallic Pd, PdO, PdOx). Increased size of Pd on catalysts' surface due to sintering, and the reduction of PdO to metallic Pd and/or PdOx were observed during the reaction. Fractions of the total surface area of different Pd species and correlations to the apparent reaction rate constants were evaluated. Apparent kinetic constants are linearly proportional to fractions of total surface areas of metallic Pd and/or reduced Pd oxide, representing the intrinsic active site. The linear correlation between the O2 reaction rate and the CO2 concentration in the initial gas stream was also observed exhibiting the possible autocatalytic effect or a surface coverage effect.

Flame and furnace aerosol reactors are used extensively for the synthesis of nanoparticles at high temperatures (800–2000 K), however, there is a limited understanding of the early stages of particle growth by collision at these temperatures. An experimental set-up to quantify the collisional growth rate and collisional correction factor (relative to the kinetic theory of gases) for flame synthesized TiO2 nanoparticles in the free molecular regime is described. Spherical charge-neutral nanoparticles with precise control of size are selected from a flame aerosol reactor (FLAR), and then passed through a downstream furnace reactor tube maintained at a high temperature. Initial and final particle size distributions (PSD) are measured using a scanning mobility particle sizer (SMPS), and the PSD is represented by a lognormal distribution. The general dynamic equation (GDE) for simultaneous coagulation and diffusive deposition is solved numerically for a laminar pipe flow using the method of moments. By comparing the experimental data with the model prediction, a correction factor to collisional growth rate is calculated. It was found that for particles in the size range 5–8 nm, there was significant enhancement in the collisional growth rate for TiO2 nanoparticles at 400 °C. This enhancement in growth rate decreased as temperature increased (upto 800 °C). The collisional correction factor values are compared to that of three existing models in the literature which predict similar trends with temperature, however, these models under-predict the value of the collisional correction factor. Reasons for these deviations from existing models are elucidated.

This paper reports the unique microstructure of polyurea foams that combines the advantages of open and closed cell polymeric foams, which were synthesized through a self-foaming process. The latter was the result of aggressive mechanical mixing of diamine curative, isocyanate, and deionized water at ambient conditions, which can be adjusted on-demand to produce variable density polyurea foam. The spherical, semi-closed microcellular structure has large perforations on the cell surface resulting from the concurrent expansion of neighboring cells and small holes at the bottom surface of the cells. This resulted in a partially perforated microcellular structure of polyurea foam. As a byproduct of the manufacturing process, polyurea microspheres nucleate and deposit on the inner cell walls of the foam, acting as a reinforcement. Since cell walls and the microspheres are made of polyurea, the resulting reinforcement effect overcomes the fundamental interfacial issue of different adjacent materials. The partially perforated, self-reinforced polyurea foam is compared to the performance of traditional counterparts in biomechanical impact scenarios. An analytical model was developed to explicate the stiffening effect associated with the reinforcing microspheres. The model results indicate that the reinforced microcell exhibited, on average, ~30% higher stiffness than its barren counterpart.

Radionuclide-stimulated therapy (RaST), which is enhanced by Cherenkov radiation, has enabled deep tissue stimulation of UV photosensitizers, providing a new path for cancer treatment. Previous reports have shown UV-active titanium dioxide (TiO2) nanoparticles (NPs) modified with transferrin inhibit tumour growth after orthogonal treatment with Cherenkov radiation-emitting radionuclides such as 18F-fluorodeoxyglucose (FDG). However, poor understanding of TiO2 NP parameters on reactive oxygen species (ROS) generation and particle distribution limits effective therapy. Here we sought to delineate the effects of crystal phase and core TiO2 crystal dimension (cTd) on ROS production and particle morphology. We prepared Transferrin (Tf)–TiO2 nanoaggregates (NAGs) using solvothermally synthesized cTd sizes from 5 to 1000 nm diameter and holo- or apo-transferrin. Holo-transferrin was unable to stabilize TiO2 NPs while apo-transferrin stabilized TiO2 into uniform nanoaggregates (NAGs), which were invariant with differing cTd, averaging 116 ± 1.04 nm for cTds below 100 nm. ROS production increased from 5 to 25 nm cTd, attaining a peak at 25 nm before decreasing with larger sizes. The supra-25 nm ROS production decrease was partially driven by a ∼1/r3 surface area decline. Additionally, amorphous TiO2 of equal core size exhibited a 2.6-fold increase in ROS production compared to anatase NAGs, although limited stability halted further use. Although both 5 and 25 nm anatase cTds formed similarly sized NAGs, 5 nm anatase showed a four-fold higher tumour-to-muscle ratio than the 25 nm NPs in tumour-bearing mice, demonstrating the intricate relationships between physical and biological properties of NAGs. The combined in vivo and ROS results demonstrate that anatase crystals and cTd size of 25 nm or less are ideal particle parameters to balance biodistribution with ROS production efficiency.

Rapid liver and spleen opsonization of systemically administered nanoparticles (NPs) for in vivo applications remains the Achilles’ heel of nanomedicine, allowing only a small fraction of the materials to reach the intended target tissue. Although focusing on diseases that reside in the natural disposal organs for nanoparticles is a viable option, it limits the plurality of lesions that could benefit from nanomedical interventions. Here we designed a theranostic nanoplatform consisting of reactive oxygen (ROS)-generating titanium dioxide (TiO(2)) NPs, coated with a tumor-targeting agent, transferrin (Tf), and radiolabeled with a radionuclide ((89)Zr) for targeting bone marrow, imaging the distribution of the NPs, and stimulating ROS generation for cell killing. Radiolabeling of TiO(2) NPs with (89)Zr afforded thermodynamically and kinetically stable chelate-free (89)Zr-TiO(2)-Tf NPs without altering the NP morphology. Treatment of multiple myeloma (MM) cells, a disease of plasma cells originating in the bone marrow, with (89)Zr-TiO(2)-Tf generated cytotoxic ROS to induce cancer cell killing via apoptosis pathway. Positron emission tomography/X-ray computed tomography (PET/CT) imaging and tissue biodistribution studies revealed that in vivo administration of (89)Zr-TiO(2)-Tf in mice leveraged the osteotropic effect of (89)Zr to selectively localize about 70% of the injected radioactivity in mouse bone tissue. A combination of small animal PET/CT imaging of NP distribution and bioluminescence imaging of cancer progression showed that a single dose (89)Zr-TiO(2)-Tf treatment in a disseminated MM mouse model completely inhibited cancer growth at euthanasia of untreated mice and at least doubled the survival of treated mice. Treatment of the mice with cold Zr-TiO(2)-Tf, (89)Zr-oxalate, or (89)Zr-Tf had no therapeutic benefit compared to untreated controls. This study reveals an effective radionuclide sensitizing nanophototherapy paradigm for the treatment of MM and possibly other bone-associated malignancies.

Titanium dioxide (TiO(2)) nanoparticles have shown success as photosensitizers in the form of light-based cancer therapy called Cerenkov radiation induced therapy (CRIT). While TiO(2) nanoparticles have been reported to be an effective therapeutic agent, there has been little work to control their functionalization and stability in aqueous suspension. In this work, the controlled coating of 25 nm diameter TiO(2) nanoparticles with the glycoprotein transferrin (Tf) for application in CRIT was demonstrated using an electrospray system. Monodisperse nanoscale droplets containing TiO(2) and Tf were dried during flight, coating the proteins on the surface of the metal oxide nanoparticles. Real-time scanning mobility particle sizing, dynamic light scattering, and transmission electron microscopy show efficient control of the Tf coating thickness when varying the droplet size and the ratio of Tf to TiO(2) in the electrospray precursor suspension. Further, the functionality of Tf-coated TiO(2) nanoparticles was demonstrated, and these particles were found to have enhanced targeting activity of Tf to the Tf receptor after electrospray processing. The electrospray-coated Tf/TiO(2) particles were also found to be more effective at killing the multiple myeloma cell line MM1.S than that of nanoparticles prepared by other reported functionalization methods. In summary, this investigation not only provides a single-step functionalization technique for nanomaterials used in Cerenkov radiation induced therapy but also elucidates an electrospray coating technique for nanomaterials that can be used for a wide range of drug design and delivery purposes.

Aim: CaCO3 nanoparticles (nano-CaCO3) can neutralize the acidic pHe of solid tumors, but the lack of intrinsic imaging signal precludes noninvasive monitoring of pH-perturbation in tumor microenvironment. We aim to develop a theranostic version of nano-CaCO3 to noninvasively monitor pH modulation and subsequent tumor response. Materials & methods: We synthesized ferromagnetic core coated with CaCO3 (magnetite CaCO3). Magnetic resonance imaging (MRI) was used to determine the biodistribution and pH modulation using murine fibrosarcoma and breast cancer models. Results: Magnetite CaCO3-MRI imaging showed that nano-CaCO3 rapidly raised tumor pHe, followed by excessive tumor-associated acid production after its clearance. Continuous nano-CaCO3 infusion could inhibit metastasis. Conclusion: Nano-CaCO3 exposure induces tumor metabolic reprogramming that could account for the failure of previous intermittent pH-modulation strategies to achieve sustainable therapeutic effect.

Antacids are crucial in the treatment of gastro-esophageal reflux disease and peptic ulcers. Antacids based on the calcite phase of bulk calcium carbonate have been the standard for over fifty years. More recent research has shown that nanomaterial forms of such bulk materials often have improved properties. However, the metastable vaterite form of calcium carbonate is particularly difficult to synthesize as a nanomaterial, and thus has not been extensively studied. Here, we describe the synthesis of these particles and investigate them for antacid applications. Experimental and computational approaches show that nanoscale vaterite particles maintain neutral gastric pH values three times longer than commercial antacids.

Polymeric foams are ubiquitous in body armors for civilian and military applications due to their functional and economic advantage. This class of materials offers good impact mitigation properties without the weight penalty associated with other classes of materials. Generally, foams inherit the mechanical properties of their base material while the performance can be defined by the cellular structure. In this study, new polyurea foams were manufactured and subjected to low energy dynamic impacts to experimentally validate the time-dependent response of polyurea foams based on linear viscoelastic modeling. The time-dependent properties of bulk polyurea were scaled down by accounting for the change in density and microstructure of the polyurea foam. Drop-weight testing of approximately 7 J in a fully-instrumented drop weight testing machine was conducted on newly-fabricated polyurea foams of two nominal densities, namely, 227 kg/m3 and 355 kg/m3. Simultaneous to the impact event, high-speed photography was used to capture the deformation and recovery response of the samples. The performance was then compared with a promising off-the-shelf, closed-cell foam material used to protect against biomechanical impacts. The polyurea foams proved to mitigate the impact more effectively than the benchmark foam without the addition of a severe weight penalty. The finite element simulation performed well in predicting the amplitude and the rise time of the dynamic impact testing of the two foams; the numerical results were found to be in close agreement with the experimental data.

A sprayable formulation of 1-methylcyclopropene (1-MCP; AgroFresh, Spring House, PA) was applied to ‘Scarletspur Delicious’ and ‘Cameo’ apples in the orchard 1 to 3 weeks before harvest and compared in different postharvest studies with the commercial postharvest 1-MCP fruit treatment (SmartFresh; AgroFresh) and with aminoethoxyvinylglycine (AVG; ReTain; Valent BioSciences, Walnut Creek, CA). Treated apples were held in air storage for 50 to 60 d or in controlled-atmosphere storage for 120 to 125 or 215 to 225 d. With increased concentration, sprayable 1-MCP treatments were effective at controlling flesh firmness loss and internal ethylene concentration (IEC) up to 225 d of storage as well as during a 7-d poststorage shelf life simulation at room temperature. Application closer to harvest improved the effect of sprayable 1-MCP on control of flesh firmness loss and IEC. Concentrations of sprayable 1-MCP above 90 mg a.i./L produced similar fruit effects to 1-MCP. Treatment with 1-MCP showed little effect on soluble solids concentration (SSC), titratable acidity (TA), or skin or flesh color in ‘Delicious’ but slightly increased SSC and TA in ‘Cameo’ apples. AVG applied 4 weeks before commercial harvest controlled IEC nearly as well as either sprayable 1-MCP or 1-MCP during storage, but AVG-treated fruit allowed to ripen for 7 d at room temperature after storage lost much more flesh firmness regardless of storage regime. Sprayable 1-MCP also reduced starch hydrolysis, IEC and fruit drop at harvest. Sprayable 1-MCP may offer new opportunities for effective preharvest management of apple fruit condition, storability, and poststorage fruit quality.

The synthetic triazole derivative 14C-labeled BAS111 (14C-BAS111) was readily translocated throughout 8-week-old apple seedlings (Malus domestica Borkh.) within 3 days of application to roots in hydroponic nutrient solution. The majority of labeled BAS111 and total 14C activity was recovered from middle leaves and root tissues. Two metabolites of labeled BAS111 were found. Both 14C-BAS111 and metabolite 1 were recovered predominantly from leaf and root tissue and from nutrient solution. Metabolite 2, however, was found almost exclusively in root tissue. The rapid degradation of 14C-BAS111 accounts for its low efficacy in comparison with other triazole growth retardants. Chemical name used: [1-phenoxy-5,5-dimethyl-3-(1,2,4-triazol-1yl)-hexan-4-ol] (BAS111).

Sweet cherry ripening is slowed during low oxygen and/or high carbon dioxide controlled atmosphere storage. Cherry flavor can be impacted by prolonged CA storage, therefore ripening after CA and storage was evaluated including production of fruit volatile compounds. `Bing' sweet cherries were harvested at commercial maturity and stored for up to 12 weeks at 1C in air or 5% O2, with 0.1, 10, 15 or 20% CO2. Fruit quality and condition were evaluated after removal from storage plus 1 or 4 days at 20C. Changes in fruit color were slow ed by all atmosphere treatments with differences most notable after longer storage durations. Volatile synthesis changed as storage duration increased, however, treatment differences were not significant. Soluble solids content was maintained at 15 and 20% CO2, but treatment differences were significant only after longer storage durations. High CO, treatments were effective at reducing decay incidence, but residual suppression after removal from storage decreased as storage duration increased. Significant treatment effects were evident for titratable acidity retention after 8 and 12 weeks storage, however, titratable acidity significantly declined in all treatments compared to the initial concentration.

Paclobutrazol, triapenthenol (RSW0411), and BAS111 were applied to 4-week-old Delicious apple seedlings (Malus domestica Borkh.) as a root drench at 0.1, 1.0, and 10.0 mg per plant. Paclobutrazol eliminated shoot extension growth for 8 weeks at all three rates. RSW0411 controlled shoot elongation only at the highest rate. BAS111 produced the widest response, with shoot growth ranging from 38% to 93% of controls for the highest and lowest rates, respectively. Generally, leaf area decreased and leaf density increased with increasing rates of all chemicals. Root weight of plants treated with paclobutrazol nearly doubled but increased only slightly with RSW0411 and BAS111. Chemical analysis of the leaf tissue 8 weeks after treatment showed paclobutrazol levels highest, followed by RSW0411 and BAS111.

A series of recovery experiments were conducted with synthetic pyrimidine and triazole derivative plant growth retardants. These studies show that significant losses occur when using common experimental procedures. An extraction process consisting of partitioning into methylene chloride, open-column chromatography on both silica and C 18 packings followed by capillary gas—liquid chromatography using nitrogen—phosphorus specific thermionic detection is outlined. This method allows sensitive and rapid isolation of these compounds with consistent recoveries (80–90%) and is thus suitable for the quantitative determination of these compounds.