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A new electron scattering apparatus is developed based on concepts from the positron system built by Surko et al (1988). In an electron version of the system, the electron beam is provided by a cathode and the rest of the system is correspondingly modified to a simpler system. The system was tested by measuring electron scattering from argon to verify its operation. N2O is important in the atmosphere and plasma processes, and in the intermediate energy region from 5 eV to 50 eV, there are two previous results for the electron scattering total cross-section which are in disagreement. We present here a new measurement for the total electron cross-section of N2O, helping to resolve this disagreement. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of temporary cement cleaning methods on the retention of cemented crowns using zinc phosphate cement and resin‐modified glass ionomer cement. Materials and Methods: Forty titanium specimens were fabricated to simulate prepared molars with minimally retentive taper. The Ni‐Cr cast crowns were fabricated, temporarily cemented, and separated. The specimens were divided into four groups according to the temporary cement cleaning method (n = 10) as follows: control group (no temporary cementation), orange solvent group, ultrasonic cleaning group, and air‐abrasion group. After the cleaning procedures, the specimens were cemented with definitive cements (zinc phosphate cement and resin‐modified glass ionomer, RMGI, cement) and subjected to thermocycling (5000 cycles, 5‐55°C, dwell time, 10 seconds). The tensile bond strength of each specimen was measured using a universal testing machine, and the results were analyzed using the Kruskal‐Wallis and Mann‐Whitney U test (α = 0.05). Results: When cemented with zinc phosphate cement, the statistical analysis showed that the value of the air‐abrasion group was significantly higher than those of the other groups (p < 0.01). There was no statistically significant difference among the other groups. When cemented with RMGI cement, the air‐abrasion group showed the lowest value, and the control group showed the highest value (p < 0.01). The difference between the ultrasonic cleaning group and the orange solvent group was not statistically significant. Conclusion: The use of temporary cement did not have a significant influence on retention of permanently cemented crowns when zinc phosphate cement was used for permanent cementation. Airborne‐particle abrasion after provisional cementation improved retention of crowns cemented with zinc phosphate cement; however, the use of temporary cement significantly decreased retention of permanently cemented crowns when RMGI cement was used regardless of the temporary cement cleaning method. [ABSTRACT FROM AUTHOR]

We report the calculations of elastic (along with its symmetry components) and electronic excitation cross sections by electron impact of the three isomers of C4F6, namely, hexafluoro-1,3-butadiene (1,3-C4F6), hexafluoro-2-butyne (2-C4F6), and hexafluorocyclobutene (c-C4F6) belonging to the point groups C2, D3d, and C2v, respectively, using the R-matrix approach. The electron energy range is from 0.01 eV to 12 eV. We have employed the cc-pVTZ basis set for C and F atoms to generate self-consistent field molecular orbitals to construct the target states for all the isomers included in our calculations. All the target states are constructed by including correlation effects in a configuration interaction (CI) approach. The target properties such as vertical excitation energies and dipole moment of all the isomers are in reasonable agreement with the literature values. Differences in the cross sections of these isomers are strongly influenced by the effect of correlation and polarization effects and their geometrical extent. We have included the ground state and many excited states of each isomer in the trial wave function of the entire scattering system. The resulting elastic cross sections are compared with the available experimental results. The agreement is reasonably good for energies above 5 eV. The shape resonances detected at 2.57, 2.95, and 3.20 eV for c-C4F6, 1,3-C4F6, and 2-C4F6 isomers are associated with the negative anion formation of C3F3- as observed in the mass spectrometry experiments. We have also performed 1-state CI calculation for all the isomers that include only the correlated ground state. The position of resonances shifts to lower energies as the number of target states is increased compared to 1-state calculation for all the isomers. The elastic cross section for 2-C4F6 isomer is larger than the other isomers because of its larger spatial extent. The present cross section data are important for plasma simulation and modeling, especially related to fluorocarbon plasma. [ABSTRACT FROM AUTHOR]

Targeting energy expenditure offers a strategy for treating obesity more effectively and safely. In previous studies, we found that the root of Atractylodes macrocephala Koidzumi (Atractylodis Rhizoma Alba, ARA) increased energy metabolism in C2C12 cells. Here, we investigated the effects of ARA on obesity and glucose intolerance by examining energy metabolism in skeletal muscle and brown fat in high-fat diet (HFD) induced obese mice. ARA decreased body weight gain, hepatic lipid levels and serum total cholesterol levels, but did not modify food intake. Fasting serum glucose, serum insulin levels and glucose intolerance were all improved in ARA treated mice. Furthermore, ARA increased peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α) expression, and the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) in skeletal muscle tissues, and also prevented skeletal muscle atrophy. In addition, the numbers of brown adipocytes and the expressions of PGC1α and uncoupling protein 1 (UCP1) were elevated in the brown adipose tissues of ARA treated mice. Our results show that ARA can prevent diet-induced obesity and glucose intolerance in C5BL/6 mice and suggests that the mechanism responsible is related to the promotion of energy metabolism in skeletal muscle and brown adipose tissues. [ABSTRACT FROM AUTHOR]