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In recent years, Hydro-Québec's Research Institute has developed, through technological innovation, a program to improve energy efficiency in the generation, transmission and distribution of energy. Among the various projects, one was focused on the production of soft magnetic materials to improve the energy efficiency of distribution transformers. The aim of the project was to produce, by electrodeposition, free-standing foils or plates of amorphous Fe-P material having similar, or better, mechanical and low loss magnetic properties compared to iron-based amorphous alloys produced by rapid solidification. To meet this goal, an electroplating process was developed to produce a well-defined binary Fe-P amorphous alloy. The key electrochemical parameters, ancillary needs, critical monitoring and process controls were investigated. We succeeded in producing a fully amorphous soft magnetic material with very low power frequency losses and other advantageous properties such as a thickness range from 20 to 75 µm with a high production rate. Using thicker material, the production of stacked cores could be possible. In addition, electroplating offers the possibility of forming complex 2D shapes for rotating machines. [ABSTRACT FROM AUTHOR]

Core/shell Fe3O4−Au/silica nanoparticles with controllable fluorescein doped into nanoporous silica shells are synthesized. The quantum yield of fluorescein significantly increases through a synthetic electromagnetic field coupling of the dumbbell-like Fe3O4−Au cores. Theoretical simulation further proves that the anomalously plasmonic oscillation of Fe3O4−Au nanoparticles is a dominant contributor to the fluorescence enhancement.

Mesoporous tantalum oxide rubidium fulleride composites were synthesized by solution impregnation and characterized by elemental analysis, X-ray diffraction, Raman spectroscopy, nitrogen adsorption/desorption, X-ray photoelectron spectroscopy, superconducting quantum interference device magnetometry, room- and variable-temperature electron transport measurements, and solid-state ⁸⁷Rb and ¹³C NMR. The room-temperature conductivity pattern, as a function of the oxidation state of C60^n-, displayed a conductivity minimum at n = 3.0 and a single maximum at n = 4.0, while variable-temperature conductivity measurements indicated that the n = 1.0 composite is a semiconductor and the n = 4.0 material is a narrow band gap semiconductor or a semimetal. Solid-state ⁸⁷Rb NMR of the composite materials indicated the presence of two Rb environments associated with the walls or channels of the mesostructure as well as several resonances associated with various fulleride species. The n = 3.0 and n = 4.0 samples showed a substantial increase of Rb ions confined into the walls of mesostructure as well as the buildup of a Rb environment associated with a fulleride species. Solid-state ¹³C NMR experiments showed the presence of multiple fulleride species as well as pure fullerene, depending on the level of reduction.

A mesoporous tantalum oxide lithium fulleride composite was synthesized by solution intercalation of C60 into a prefabricated Li-TaTMS material and characterized by elemental analysis, X-ray diffraction (XRD), Raman spectroscopy, nitrogen adsorption−desorption, X-ray photoelectron spectroscopy (XPS), superconducting quantum interference device (SQUID) magnetometry, and solid-state ¹³C and ⁷Li NMR. The room conductivity measurements of Li fulleride material showed that this material was insulating, as opposed to previously synthesized K and Na based mesoporous Ta oxide fulleride composites with similar composition, which were semiconducting or metallic. Solid-state ⁷Li NMR of this lithium composite exhibited a single Li environment. XPS measurements indicated an oxidation of the tantalum oxide walls had occurred upon intercalation of the fullerene ¹³C NMR, and Raman measurements were consistent with one fulleride species in the pores. Electrochemical measurements revealed largely irreversible behavior upon intercalation/deintercalation of Li⁺ into this material. This was attributed to the insulating nature of this composite impeding charge transport through the channels. In contrast, the corresponding Na fulleride intercalate showed reversible Li insertion, possibly due to enhanced charge transport through the semiconducting structure.

Mesoporous tantalum oxide–sodium fulleride composites were synthesized by solution impregnation and characterized by elemental analysis, X‐ray diffraction (XRD), Raman spectroscopy, nitrogen adsorption–desorption, X‐ray electron photoelectron spectroscopy (XPS), superconducting quantum interference device (SQUID) magnetometry, variable‐temperature electron transport measurements, and solid‐state 13C and 23Na NMR spectroscopy. The room temperature conductivity pattern as a function of sodium reduction level displayed a minimum at n= 3.0 and a maximum at n= 4.5, where nis the formal charge on the fulleride. The variable‐temperature conductivity measurements demonstrated that the n= 0.5 and n= 4.5 materials were semiconductors. Solid‐state 23Na NMR spectroscopy of the n= 0.5 composite exhibited three Na environments in the composites: two associated with the tantalum oxide walls and a third associated with the fulleride. The n= 3.0 and n= 4.5 materials showed a large build‐up of Na ions in the wall with no visible Na resonances associated with the fulleride, suggesting a structure in which the fulleride units exist as naked anions in one‐dimensional chains surrounded first by a layer of Na ions and then by a layer of mesoporous tantalum oxide. Solid‐state 13C NMR experiments showed more than one fulleride species in both the n= 0.5 and the n= 4.5 composites, as well as pure C60in the n= 0.5 material, but almost exclusively C603–in the n= 3.0 material. The retention of carbon throughout reduction suggests that polymerization may have occurred, however this could not be verified by 13C NMR spectroscopy, because the region where sp3fullerene resonances normally appear was obscured by solvent peaks.

Mesoporous niobium oxide potassium fulleride composites were synthesized by the treatment of mesoporous niobium oxide with 0.3, 0.6, or 1.0 equiv of potassium naphthalene followed by stirring with either excess K3C60 or C60. The reaction of potassium-reduced mesoporous niobium oxide with neutral C60 is the first reported example of a mesoporous oxide functioning as an electron donor to a guest molecule. These new routes allow for greater flexibility in the K:Nb and C:Nb ratios in the composite than our previous method and for this reason enables a more comprehensive study of the effect of absolute carbon and potassium content on electron transport properties. Materials were characterized by elemental analysis, nitrogen adsorption, XRD, XPS, SQUID magnetometry, and room-temperature conductivity measurements in an effort to relate density of states at the Fermi level, temperature-independent paramagnetism, and conductivity patterns to the composition of the composite. Variable temperature resistivity measurements showed that the composites are metallic, semiconducting, or insulating, depending on the composition. The main factors governing conductivity were the absolute carbon content and the oxidation state of the intercalated fulleride, while the absolute potassium content had little effect on the electronic properties.

Mesoporous niobium oxide was treated at room temperature with bis(toluene) niobium to make a new black material that exhibits metallic properties. The metallic behavior is attributed to low‐valent NbIIin the walls of the porous structure and is fully supported by strong emissions at the Fermi level, variable temperature resistivity measurements, and temperature‐independent paramagnetism. These materials possess higher conductivities than reported for any molecular sieve and also represent the first example of a metallic oxide‐based molecular sieve. For comparison, the conductivity is almost 10 000 times greater than the highest value measured for an open structured mesoporous material. Treatment at room temperature with dinitrogen leads to formation of a thin nitride coat on the surface. Cleavage of dinitrogen is an extremely rare and important reaction that typically requires very forcing conditions in the solid state (high temperatures in excess of several hundred degrees, argon plasmas, etc.) or low‐valent coordinatively stressed metal centers in the homogeneous phase. This is the first example of a molecular sieve mediating this process and because of the controlled porosity and high surface areas of these materials they are ideal candidates for model studies for nitrogen reduction and catalytic nitrogen incorporation into organic compounds. Since porous materials are often the catalytic support of choice for industrial processes, these materials may lead to the development of commercial nitrogen incorporation processes.

New composites of mesoporous niobium oxide with mixed oxidation state bis(cyclopentadienyl)vanadium and -chromium phases in the pores were synthesized and characterized by X-ray powder diffraction, nitrogen adsorption, UV, electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), and superconducting quantum interference device magnetometry. The XPS and EPR revealed that the walls of the mesostructure in both composites were reduced and that the organometallic had retained its structural integrity as a combination of neutral and cationic metallocene species. The conductivity of these materials ranged from 10^-4 to 10^-6 Ω^-1 cm^-1 and was attributed to the mixed oxidation state organometallic phase since previous studies showed that the reduced niobium oxide mesostructure is inherently insulating. The Hubbard model involving the bandwidth and the Hubbard potential was invoked using electron affinities, ionization potentials, and bandwidths of the organometallic species to verify the model involving electron mobility through the mixed oxidation state organometallic phase. Comparisons to previously studied insulating cobaltocene composites of mesoporous niobium oxide were made in an effort to determine the main factors governing conductivity in these systems.

Recent results in our group demonstrated that KnC60 (n = 3), a much-studied superconductor and molecular metal, can be encapsulated in the channels of mesoporous niobium oxide to make pseudo-one-dimensional alkali fulleride wires. The oxidation state of the encapsulated fulleride phase can be tuned by addition of potassium naphthalene to the mesostructured composite. Surprisingly, the conductivity of this series of composites has maxima at n = 2.6 and n = 4.1, rather than n = 3 as in the bulk material. In this work, we report a study on the effect of changing the pore size and wall composition of the mesoporous host lattice on the conductivity and electronic behavior of the corresponding potassium fulleride composites. Samples of mesoporous niobium oxide with a 32-Å pore size, mesoporous tantalum oxide with a 22-Å pore size, and mesoporous titanium oxide with a 22-Å pore size were treated with K3C60 and characterized by elemental analysis, nitrogen adsorption, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), electron spin resonance spectroscopy (ESR), and superconducting quantum interference device (SQUID) magnetometry. These materials were then further reduced with small aliquots of potassium naphthalene in sequential steps up to a fulleride oxidation state of n = 4.5, and each material was fully characterized as described above. For each series of materials, two conductivity maxima were observed, the first at approximately n = 2.5 and the second at roughly n = 4.0, indicating that this double-maxima behavior is general to other one-dimensional alkali fulleride mesostructures. There was no clear pattern in the effect of changing pore size and wall composition on the electronic properties; however, all materials near n = 4.0 showed a greater degree of reduction of the mesostructure and a greater density of states near the Fermi level as determined by XPS, consistent with the high levels of conductivity of the fulleride at this oxidation state.

Herein we report the synthesis and characterization of a new family of mesoporous niobium oxide bis(cyclopentadienyl)nickel composites which exhibit superparamagnetic or spin glass behavior depending on the different loading levels of the organometallic in the pores. XRD and nitrogen adsorption studies confirm the retention of the mesostructure in these new materials upon introduction of the guest species. The Nb 3d region of the XPS provides evidence for the slight reduction of the Nb(V) oxide walls while the Ni 2p region shows the presence of both neutral and cationic bis­cyclopentadienyl nickel species with peaks at 856.3 eV and 861.9 eV respectively, as well as two more highly oxidized species at 865.5 eV and 867.3 eV. The presence of neutral and cationic bis(cyclopentadienyl)nickel is further confirmed by EPR. SQUID magnetic measurements show superparamagnetic behavior for the material with a Ni∶Nb ratio of 0.07∶1, while at a ratio of 0.1∶1 the material shows spin glass behavior, a phenomenon normally associated with amorphous metal alloys. The difference in magnetic behavior is rationalized by an increased density of unpaired spins in the pore structure.

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Nanostructured CeO2-x and Cu0.15Ce0.85O2-x were synthesized by high-pressure magnetron sputtering. X-ray diffraction was used for phase analysis and grain size characterization. The structural analysis indicated that Cu was highly dispersed, which could be explained by surface segregation on cerium oxide nanocrystals. The reduction and oxidation of dispersed copper in nanostructured Cu0.15Ce0.85O2-x was investigated by isothermal gravimetric analysis (IGA) and X-ray photoelectron spectroscopy (XPS). In IGA, the sample weight was measured at constant temperature during in situ reduction and oxidation in 2% CO/He or 5% H2/He and 15% O2/He, respectively. The weight changes of microcrystalline CeO2 and nanocrystalline CeO2-x and Cu0.15Ce0.85O2-x samples were measured at temperatures between 200 and 500 °C. The analysis revealed that more than one oxygen atom was extracted per Cu atom in Cu0.15Ce0.85O2-x during reduction, which was reversibly restored during oxidation. The Cu valence state in Cu0.15Ce0.85O2-x after oxidation or reduction was independently determined by XPS. The Cu 2p core-level spectra and LMM Auger spectra of Cu0.15Ce0.85O2-x were compared with those of a polycrystalline copper reference. The analysis showed that all three oxidation states of copper (i.e., 0, 1+, and 2+) could be present depending on the reduction/oxidation specifications. Furthermore, Cu⁰ and Cu¹⁺ were found to coexist in a stable state under certain conditions.

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Numerous publications have reported inconsistent growth performance responses when protease and carbohydrase enzymes are added to swine diets. Therefore, we conducted a meta-analysis to quantify the responses based on dietary grain sources, enzyme type, high fiber by-products (NDF > 20%), phytase inclusion, experiment duration, and pig age on growth performance for pigs fed different diets. The mean differences (MD) of exogenous proteinase or carbohydrase supplementation effects on ADG, ADFI, and gain efficiency (G:F) were expressed as a percentage compared with control diets without enzymes. Data from 101 studies with 279 observations were included in the database. Positive-results publication bias was observed for corn-based diets (ADG, ADFI, and G:F), indicating non-significant results may be underrepresented in the data set. The MD of ADG of pigs was increased (P< 0.01) when proteinase or carbohydrases were added to diets with corn (2.07%), wheat (3.04%), barley (1.51%), and other grains such as rye, triticale, oat, sorghum, or broken rice (2.68%). The presence of phytase increased (P< 0.05; 4.23 vs. 3.06%) the MD of ADG for pigs fed corn-based diets. Supplementing enzyme complex (proteinase + carbohydrases) in corn based diets had greater MD of ADG (P< 0.05; 4.12 vs. 2.31%) than inclusion of a single carbohydrase. Gain:Feed was improved (P< 0.05) by 1.56, 2.78, 2.70, and 2.14% with exogenous enzyme supplementation in pig diets containing corn, wheat, barley or other grain-based diets, respectively. The inclusion of high fiber by-products (including corn distilers dried grain solubles, wheat middlings, wheat bran, wheat dried distillers grains, cotton seed meal, rapeseed meal, and others) did not affect the MD of growth performance in different grain-based diets. In conclusion, the addition of phytase and protease may enhance the improvements in pig growth performance when carbohydrases are supplemented in corn based diets.

The bacterium, Lawsonia intracellularis,causes proliferative enteropathy in a variety of species, most notably pigs. The mechanism for intestinal epithelial cell expansion during a L. intracellularisinfection is not well understood, and development of a suitable in vitromodel is needed. Enteroids are 3-dimensional structures grown in vitro,and containing the differentiated cells of the small intestine. Consequently, our objective was to develop an enteroid infection model for L. intracellularisusing enteroids. Because L. intracellularisis a slow-growing bacterium, in vitromodels must provide normal cell proliferation for extended time (5-28 d). Although enteroid culture techniques are well established for mice, this species may not be the best model for L.intracellularisinfection because the severity of lesions in mice are not as intense as observed in pigs. While L. intracellulariscauses disease and reduced profitability in swine production, there is limited information on effective methods to culture swine enteroids. Thus, we first tested the feasibility of infecting mouse enteroids with the bacteria, and then proceeded to develop a protocol for swine enteroid culture to evaluate L. intracellularisinfection in swine. Mouse enteroids were successfully infected with L. intracellularisby microinjecting the bacterial suspension into the lumen of the enteroids, which resulted in immunohistochemical localization of L. intracellularisin the enteroid. To develop swine enteroids, intestinal crypts were isolated from sections of jejunum collected from finishing pigs by dissociation using ethylenediaminetetraacetic acid. The crypt suspension was pelleted by centrifugation and re-suspended in culture medium. Isolated crypts were mixed with Matrigel, and plated in 24-well plates forming firm Matrigel beads. Enteroid medium was added to the wells once Matrigel solidified. Medium was changed every 2 d, and enteroids were passaged once a wk. At 10 d, enteroids had an average diameter of 106 μm with 3 enteroids per well. Enteroids survived for a maximum of 50 d, and longest survival was in broken pieces of Matrigel that had separated from the firm Matrigel beads. We then determined if suspended pieces of Matrigel would enhance swine enteroid development in a second experiment. In broken Matrigel, enteroids survived for 28 d. By 10 d, enteroids had an average size of 76.3 μm and there were 16 enteroids per well. This approach provided a 3-wk time period where enteroids were useful for pathogen infection experiments. This infection model may be useful in determining mechanisms of the pathogenesis of L. intracellularisand potential treatment options.

Docetaxel is a new taxoid drug with good activity against human breast cancer cells in vitro; a number of partial and minor responses have been obtained during phase I studies in patients with advanced breast cancer. In phase II trials, first-line use of docetaxel has produced an overall response rate (OR) of up to 73%. In addition, docetaxel has shown good activity when given as second-line therapy (OR 38%), particularly in patients with disease refractory to anthracyclines (OR 55%). Indeed, the high response rate in this latter group of patients clearly warrants further investigation of docetaxel in this setting. Neutropenia is the major dose-limiting toxicity of docetaxel, but other haematological effects are rare. Hypersensitivity and cutaneous reactions are ameliorated by premedication with corticosteroids and histamine antagonists; fluid retention may improve with longer use of prophylactic premedication. Docetaxel is mildly emetogenic, but no other premedication is necessary. In summary, docetaxel is an active new drug in the treatment of advanced breast cancer. Its role in the management of early stage disease awaits the results of prospective randomised trials.

Rapeseed meal (RSM) is a rich source of AA, lipids, fiber, minerals, and vitamins. Despite its favorable nutrient content, the antinutrient properties of bioactive phytochemicals within rapeseed pose challenges in adopting rapeseed meal as a major component of swine feed. In this study, the control diet containing 14% soybean meal (SBM) and the rapeseed diet containing 20% RSM were formulated to have similar NE and standardized ileal digestible AA content. To understand the influences of RSM feeding on metabolic homeostasis, 40 nursery pigs, 17.8 ± 2.7 kg initial BW, were equally spilt into 2 groups and pair fed with control and rapeseed diets, respectively. On d 21, all pigs were sacrificed for harvesting serum, digesta, and liver samples. All samples were examined by LC-MS–based metabolomic analysis for determining the metabolic effects of these 2 diets. Rapeseed exposure markers, including sinapine, sinapic acid, and gluconapin, were identified in the digesta by an unsupervised principal component analysis (PCA) model and metabolite characterization, Furthermore, different distribution of free AA in the intestine was observed between the 2 meals. However, feeding RSM did not significantly affect the levels of microbial metabolites in the digesta, including short-chain fatty acids and secondary bile acids, in spite of 2% greater NDF content. As for serum and liver extracts, the separation of rapeseed diet from control was achieved only in the supervised partial least squares-discriminant analysis (PLS-DA) model but not in the PCA model, suggesting that limited metabolic differences existed between the 2 feeding groups. Nevertheless, oxidized metabolites, including oxidized glutathione, cystine, and pyroglutamate, as well as the triacylglycerol:phospholipid ratio were positively correlated with rapeseed diet in the model, whereas ascorbic acid in the liver was negatively associated with it. These observed metabolic changes suggest the occurrence of oxidative stress after short-term RSM feeding and warrant further studies on their correlations with growth performance in long-term feeding.