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Silicon Carbide (SiC) Power Devices have emerged as a breakthrough technology for a wide range of applications in the frame of high-power electronics, notably in the 600 to 3,300V. The last decades have shown a continuous and impressive improvement in both 4H-SiC wafer size and quality. Nevertheless, the availability of such wafers remains a challenge for the SiC power industry. In the last three years, Soitec has successfully adapted the Smart Cut™ technology to Silicon Carbide, resulting in the integration of a thin layer of high quality 4H-SiC on an ultra-low resistivity 3C p-SiC handle wafer. The so-called SmartSiC™ offers a drastic yield improvement for the whole industry thanks to the multiple times re-use of the 4H-SiC donor wafer, as well as an improvement of the device’s electrical performance, especially thanks to the ultra-low resistivity polycrystalline silicon carbide (p-SiC). The latter being specially developed to enhance the new SmartSiC™ substrate capabilities. In this paper, we present the work done by Mersen and Soitec to tailor the p-SiC properties, and thus the SmartSiC™ ones including such material.

Des substrats en carbure de silicium et nitrure d'aluminium ont été élaborés par Spark Plasma Sintering en vue de réaliser des refroidisseurs pour l'électronique de puissance. La température et la pression lors de l'élaboration doivent être maximisées pour atteindre des densités relatives proches des densités théoriques de chaque matériau. Les comportements mécanique et électrique des céramiques ont été établis à l'aide d'une approche microstructures/propriétés. Les porosités jouent un rôle très important sur le comportement mécanique et électrique des matériaux. Il apparaît également que les propriétés électriques de l'AlN SPS sont supérieures à celles de l'AlN fritté conventionnellement montrant que le procédé d'élaboration SPS n'induit pas d'impuretés dans le matériau. Les propriétés électriques du SiC SPS sont largement inférieures à celle du SIC fritté conventionnellement avec du bore comme ajout de frittage indiquant le rôle important de la qualité chimique des poudres utilisées pour le frittage.

ABSTRACTMethicillin-resistant Staphylococcus aureus(MRSA) has become one of the most significant pathogens affecting global public health and health care systems. In Canada and the United States, the spread of MRSA is primarily attributed to a single dominant epidemic clone: CMRSA10/USA300. Despite this, the CMRSA7/USA400 epidemic clone has been reported to be the predominate epidemic clone in several Canadian provinces and some parts of the United States. This study examined the epidemiology of CMRSA7/USA400 MRSA in Alberta, Canada, from June 2005 to December 2012. Molecular characterization of CMRSA7/USA400 isolates was done using spa, SCCmec, PVL, and PFGE typing and identified two predominant spatypes in Alberta: t128 and t1787. Although closely related, these spatypes have distinct geographic distributions. From 2010 to 2012, the number of t128 infections has remained stable while there has been a nearly 3-fold increase in the number of provincial t1787 infections, accompanied by 10-fold increases in t1787 infection rates in some communities. Most t128 and t1787 patients were First Nations or Inuit people, and isolates were usually from skin and soft tissue infections in outpatients. t128 patients were significantly older than t1787 patients. Antimicrobial susceptibility testing showed higher mupirocin resistance in t1787 than in t128 MRSA. Improved strategies to reduce or stabilize t1787 infections in Alberta are needed.

The European FP7 project HycycleS focuses on providing detailed solutions for the design of specific key components for sulphur-based thermochemical cycles for hydrogen production. The key components necessary for the high temperature part of those processes, the thermal decomposition of H 2 SO 4 , are a compact heat exchanger for SO 3 decomposition for operation by solar and nuclear heat, a receiver-reactor for solar H 2 SO 4 decomposition, and membranes as product separator and as promoter of the SO 3 decomposition. Silicon carbide has been identified as the preferred construction material. Its stability is tested at high temperature and in a highly corrosive atmosphere. Another focus is catalyst materials for the reduction of SO 3 . Requirement specifications were set up as basis for design and sizing of the intended prototypes. Rigs for corrosion tests, catalyst tests and selectivity of separation membranes have been designed, built and completed. Prototypes of the mentioned components have been designed and tested.

Recombinant human pancreatic lipase-related protein 2 (rHPLRP2) was produced in the protease A-deficient yeast Pichia pastoris. A major protein with a molecular mass of 50 kDa was purified from the culture medium using SP-Sepharose and Mono Q chromatography. The protein was found to be highly sensitive to the proteolytic cleavage of a peptide bond in the lid domain. The proteolytic cleavage process occurring in the lid affected both the lipase and phospholipase activities of rHPLRP2. The substrate specificity of the nonproteolyzed rHPLRP2 was investigated using pH-stat and monomolecular film techniques and various substrates (glycerides, phospholipids, and galactolipids). All of the enzyme activities were maximum at alkaline pH values and decreased in the pH 5–7 range corresponding to the physiological conditions occurring in the duodenum. rHPLRP2 was found to act preferentially on substrates forming small aggregates in solution (monoglycerides, egg phosphatidylcholine, and galactolipids) rather than on emulsified substrates such as triolein and diolein. The activity of rHPLRP2 on monogalactosyldiglyceride and digalactosyldiglyceride monomolecular films was determined and compared with that of guinea pig pancreatic lipase-related protein 2, which shows a large deletion in the lid domain. The presence of a full-length lid domain in rHPLRP2 makes it possible for enzyme activity to occur at higher surface pressures. The finding that the inhibition of nonproteolyzed rHPLRP2 by tetrahydrolipstatin and diethyl-p-nitrophenyl phosphate does not involve any bile salt requirements suggests that the rHPLRP2 lid adopts an open conformation in aqueous media.

Silicon carbide and aluminium nitride substrates were developed by Spark Plasma Sintering for power electronics coolers. The temperature and pressure during the sintering must be maximized to achieve relative densities close to the theoretical densities of each material. The study of the massive ceramics owes to establish some relations between microstructure and physical properties. The porosity play an important role in the electrical and mechanical behaviour of materials. It also appears that the electrical properties of AlN SPS are higher than those of conventionally AlN sintered showing that the SPS process does not involve impurities in the material. The electrical properties of SiC SPS are much lower than that of SiC conventionally sintered with the addition of boron as sintering indicating the important role of chemical powder used for sintering. Des substrats en carbure de silicium et nitrure d'aluminium ont ?t? ?labor?s par Spark Plasma Sintering en vue de r?aliser des refroidisseurs pour l'?lectronique de puissance. La temp?rature et la pression lors de l'?laboration doivent ?tre maximis?es pour atteindre des densit?s relatives proches des densit?s th?oriques de chaque mat?riau. Les comportements m?canique et ?lectrique des c?ramiques ont ?t? ?tablis ? l'aide d'une approche microstructures/propri?t?s. Les porosit?s jouent un r?le tr?s important sur le comportement m?canique et ?lectrique des mat?riaux. Il appara?t ?galement que les propri?t?s ?lectriques de l'AlN SPS sont sup?rieures ? celles de l'AlN fritt? conventionnellement montrant que le proc?d? d'?laboration SPS n'induit pas d'impuret?s dans le mat?riau. Les propri?t?s ?lectriques du SiC SPS sont largement inf?rieures ? celle du SIC fritt? conventionnellement avec du bore comme ajout de frittage indiquant le r?le important de la qualit? chimique des poudres utilis?es pour le frittage.

Background & Aims: The lipolytic potential of digestive lipases in vivo has always been deduced so far from their in vitro activities under nonphysiologic conditions. In the present study, the specific activities of human gastric lipase (HGL) and pancreatic lipase (HPL) were measured on dietary triglycerides (TGs) during test meal lipolysis. Methods: Healthy human volunteers ingested a liquid or solid meal. The specific activities of HGL and HPL were estimated from the lipase and free fatty acid (FFA) outputs at the postpyloric and duodenal levels, respectively. Based on the in vivo data, lipolysis was also performed in vitro by mixing the meal either with gastric juice and subsequently with pancreatic juice and bile or with purified HGL and HPL. FFAs were measured by thin-layer chromatography, and the specific activities of HGL and HPL were expressed as micromoles of FFA per minute per milligram of lipase. Results: In vitro, the specific activities on the liquid meal TGs were 32 (gastric juice) and 34 (pure lipase) @mmol . min^-^1 . mg^-^1 with HGL and 47 (pancreatic juice) and 43 (pure lipase) @mmol . min^-^1 . mg^-^1 with HPL. The specific activities on the solid meal TGs were 33 (gastric juice) and 32 (pure lipase) @mmol . min^-^1 . mg^-^1 with HGL and 12 (pancreatic juice) and 15 (pure lipase) @mmol . min^-^1 . mg^-^1 with HPL. The in vivo values obtained were in the same range. The secretory lipase outputs were 21.6 +/- 14.5 mg HGL and 253.5 +/- 95.5 mg HPL with the liquid test meal and 15.2 +/- 5.1 mg HGL and 202.9 +/- 96.1 mg HPL with the solid test meal. Conclusions: The specific activities of HGL and HPL on meal TGs were much lower than those measured in vitro under optimized assay conditions (1300-8000). However, these low specific activities are enough for the meal TGs to be completely lipolysed, given the amounts of HGL and HPL secreted during a meal.

We have carried out pressure studies on three pure compounds, viz., di-(4'-n -octyloxyphenyl)-trans-cyclohexane-1, 4-dicarboxylate), p-n-nonyloxybenzoic acid and n-pentyl-4 (4'-n-decyloxybenzylideneamino) cinnamate, each of which exhibits the smectic C phase but the nature of the temperature variation of the tilt angle being different in the three cases. It is found that for all the compounds the smectic C phase is suppressed at high pressures.

The homologous Series of trans-1,4-cycolhexane-di-4'-n-alkoxybenzoates in which the alkyl group is C1-C8, C10, C12, C14 and C16 has been prepared by esterification of trans-1,4-cyclohexanedicarbonyl chloride with 4-alkoxyphenols. Mesomorphic properties and phase transitions have been determined using polarizing hot-stage microscopy and DSC. A comparison of the data for this series with those for the analogous terephthalic acid diesters gives some insight into the effect of a cyclohexane ring on mesomorphic propertries. Relationships between thermal and x-ray data and structures are discussed.

Lipase from Pseudomonas aeruginosais a Mr, 29 kDa protein with a single functional disulfide bond as shown by a shift in electrophoretic mobility after treatment with dithiothreitol and iodoacetamide. Limited proteolysis of lipase with Staphylococcus aureusprotease V8 resulted in cleavage after amino acid residues Asp38and Glu46. Comparison of the lipase amino acid sequence with those of other hydrolases with known 3D structures indicated that the folding pattern might be compatible with the α/β hydrolase fold, thereby allowing us to construct a 3D model which fitted the biochemical properties. The model predicts a catalytic triad consisting of Ser82, Asp229and His251, and contains a disulfide bond connecting residues Cys183and Cys235. Residues Asp38and Glu46are located at the surface of the enzyme, whereas the disulfide bond is rather inaccessible, which is in agreement with the finding that the protein needed to be partly unfolded before a reduction of the disulfide bond could take place. A striking prediction from the model was the lack of a lid‐like α‐helical loop structure covering the active site which confers to other well‐characterized lipases a unique property known as interfacial activation. Experimental determination of lipase activity under conditions where the substrate existed either as monomeric solutions or aggregates confirmed the absence of interfacial activation.

Lipase activity was measured in supernatant homogenates from various anatomic regions in the upper part of the human digestive tract of two organ donors. It is shown unambiguously that lipase activity occurs only in the fundic mucosa of the stomach, whereas no significant activity takes place in the antral, pharyngeal, or lingual areas, including the circumvallate papillae. In adults, the potential activity of human gastric lipase, as measured using tributyrin as substrate, amounts to 20% of its pancreatic counterpart. Lipase activity was also determined on human gastric biopsy samples taken during gastrofibroscopy tests on healthy adults. These results confirmed the finding that a lipolytic activity of gastric origin occurs uniformly and only in the fundic mucosa. Triacylglycerol hydrolysis is associated with a genuine gastric lipase activity that is clearly distinct from the classical esterase observed using p-nitrophenyl acetate as substrate. Lipase activity decreases significantly with age: it ranges on average from 4700 U/g of fresh mucosa in subjects aged up to 50 yr to 700 U/g of fresh mucosa in persons over 60 yr of age.

Improvements in the O-alkylation of 4-substituted phenols with alkyl bromides in the presence of base by using anhydrous conditions has led to better methods for the preparation of 4-substituted alkoxybenzenes in which the substituent is either an aldehyde or a protected functional group. The protected groups can be benzyloxy, acetamido and carboxylic acid methyl ester which are easily converted to hydroxy, amino and acid chloride groups. A mixture of N,N-dimethylformamide and benzene containing molecular sieves and sodium hydroxide as the base along with an azeotropic distillation provides the necessary anhydrous conditions to avoid hydrolysis of the protecting groups. A variety of mesomorphic compounds such as 4,4'-disubstituted phenylbenzoates, phenylthiobenzoates, benzylideneamino (Schiff's bases) compounds and azoxybenzenes in which at least one of the terminal substituents is an alkoxy group can be prepared from these 4-substituted alkoxybenzenes.

The pancreas expresses several members of the lipase gene family including pancreatic triglyceride lipase (PTL) and two homologous proteins, pancreatic lipase-related proteins 1 and 2 (PLRP1 and PLRP2). Despite their similar amino acid sequences, PTL, PLRP1, and PLRP2 differ in important kinetic properties. PLRP1 has no known activity. PTL and PLRP2 differ in substrate specificity, bile acid inhibition, colipase requirement, and interfacial activation. To begin understanding the structural explanations for these functional differences, we solved the crystal structure of rat (r)PLRP2 and further characterized its kinetic properties. The 1.8 Å structure of rPLRP2, like the tertiary structure of human PTL, has a globular N-terminal domain and a β-sandwich C-terminal domain. The lid domain occupied the closed position, suggesting that rPLRP2 should show interfacial activation. When we reexamined this issue with tripropionin as substrate, rPLRP2 exhibited interfacial activation. Because the active site topology of rPLRP2 resembled that of human PTL, we predicted and demonstrated that the lipase inhibitors E600 and tetrahydrolipstatin inhibit rPLRP2. Although PTL and rPLRP2 have similar active sites, rPLRP2 has a broader substrate specificity that we confirmed using a monolayer technique. With this assay, we showed for the first time that rPLRP2 prefers phosphatidylglycerol and ethanolamine over phosphatidylcholine. In summary, we confirmed and extended the observation that PLRP2 lipases have a broader substrate specificity than PTL, we demonstrated that PLRP2 lipases show interfacial activation, and we solved the first crystal structure of a PLRP2 lipase that contains a lid domain.

Aim. To assess changes in the craniocervical structure and in hyoid bone position in skeletal Class II subjects with and without temporomandibular disorders (TMD). Materials and Methods. The cephalometric analysis of 59 subjects with skeletal Class II was evaluated and compared. The measurements considered were ANB as a parameter of Class II and C0-C1 distance, C1-C2 distance, craniocervical angle, and hyoid bone position for the cervical spine analysis. Patients were divided into patients with TMD (group A) and patients without TMD (group B). TMD were evaluated with Diagnostic Criteria for TMD (DC/TMD). Descriptive statistics and Pearson’s and Spearman’s correlation analysis, with p value <0,005, were performed. Results. C0-C1 and C1-C2 distance values and hyoid bone position resulted within the normal range in the majority of patients examined. Craniocervical angle was altered in 33 patients. The reduction of this angle with the increase of the ANB value resulted to be statistically significant in group A, according to Pearson’s correlation index. No other data were statistically significant. Conclusions. The significant relationship between skeletal Class II and cervical spine cannot be highlighted. The alteration of craniocervical angle seems to be mildly present, with backward counterclockwise rotation of the head upon the neck in the sample (groups A and B). The presence of TMD as a key factor of changes in neck posture could explain the different result between the two groups about the relationship between ANB and craniocervical angle. This result should be further analyzed in order to better understand if cervical spine changes could be related to mandibular postural ones in the craniocervical space or to temporomandibular joint retropositioning, more recognizable in Class II with TMD, which could determine functional changes in other structures of this unit; neck posture could be the result of a compensatory/antalgic mechanism in response to TMD.

Presents the poem "Wagon Train Drive," by Christy Ferrato. First Line: In the summer of 1996, the Bekins movers arrived at our house; Last Line: and started our new life out West.