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We have compared measures of heart rate variability (HRV) in 15 women in late pregnancy before and 3 months after delivery and in 20 non-pregnant controls, to study the effect of aortocaval compression on autonomic nervous activity. Normalized high-frequency power was used as an index of vagal activity and the low-/high-frequency power ratio as index of sympathovagal balance. We found that the decrease in vagal activity and increase in sympathovagal balance before delivery returned to normal 3 months after delivery. Percentage changes in vagal activity and sympathovagal balance 3 months after delivery in the left lateral decubitus position were least among three recumbent positions. The relief of aortocaval compression as a result of delivery of the fetus may be the main cause of return of autonomic nervous activity 3 months after delivery. Postpartum hormonal changes may also contribute to return of autonomic nervous activity after delivery.

A total of 246 live Clostridium difficile cultures were serotyped by a slide agglutination technique. Fifteen grouping antisera were produced which serotyped 98% of the cultures (241 of 246). Our results indicated that certain serogroups may have specific pathogenicity. Strains of serogroups A, G, H, K, S1, and S4 were cytotoxigenic and were isolated mainly from adult patients with pseudomembranous colitis or antibiotic-associated diarrhea. Nontoxigenic strains of serogroups D and Cd-5 were isolated mainly from asymptomatic neonates and small children. Some cross-reactions occurred among some strains of serogroups A, Cd-5, G, and K. These strains were further examined by analysis of protein profiles and restriction endonuclease patterns to elucidate their serology. Typing of C. difficile by using slide agglutination is a simple technique suitable for routine examination. Serogrouping may be a useful epidemiological marker and could help in elucidating the medical relevance of some C. difficile isolates.

Heating solutions of acetal complexes {CpRu(CH3CN)2[η¹-P-2-(Ph2P)[CH(OR)2]C6H4]}OTf (3; R = Me, Et) at 60−95 °C results in loss of one CH3CN ligand and the alcohol ROH, with concomitant formation of carbene complexes CpRu(CH3CN)[η²-C,P-2-(Ph2P)[C(OR)]C6H4]}OTf (4) in high yield. Kinetic and reactivity studies suggest that the rate-determining step of the conversion of 3 to 4 is oxidative addition of an acetal C−O bond to the ruthenium center, which occurs under neutral, mild conditions.

A diffused germanium (Ge) p-n junction as a Ge-subcell was fabricated by using an overall Ge-based triple-junction structure to evaluate its photovoltaic properties. The key processes in the proposed Ge-subcell include: (i) patterning a contact window with 5% area of the Ge-subcell to form top electrodes and (ii) semiconductor layers grown for the InGaP top cell and the (In)GaAs middle cell are remained atop of the Ge-subcell. Thus, our Ge-subcell has a duplicate of absorption spectrum of the Ge bottom cell in the triple-junction solar cell. Important photovoltaic parameters extracted showed that the photo-generated current density is ∼26 mA/cm2being independent of the testing temperature. Besides, open-circuit voltages linearly decrease with increasing temperature and hence the Ge-subcell cannot act as a practical solar cell when temperature is higher than ∼140°C. Furthermore, maximum conversion efficiency (ηmax) at 30°C is 3.22% for the intrinsic Ge-subcell. A corresponding temperature coefficient is ∼−0.037%/°C. Cell temperature of our Ge-subcell under a 100 mW/cm2simulator increases quickly to saturate at ∼48°C. This causes reduction of more than 0.8% in ηmax.

Introduction The most common complication of osteoporotic is vertebral compression in aged people. Pain and disability pose major problems in these patients. To restore the vertebral height for driving physical stiffness, and loading bearing toward normal limited, kyphoplasty and vertebroplasty with variable filling materials (PMMA, CPC, etc.) have been used for the treatment. For decreasing the rate of PMMA leakage, we performed kyphoplasty with eggshell technique in different characteristics of vertebral wall.Materials and Methods Twenty symptomatic vertebral fractures were enrolled. Visual analogue scale (VAS), the oswestry disability index (ODI), and vertebral wall injury score were assessed. The vertebral height loss and changes of kyphotic angle were also recorded by plain X-ray. Three-dimensional CT will be arranged for evaluating the condition of deficiency vertebral wall and central body collapse if needed. After creating cavity by percutaneous bipedicular balloon device, PMMA was injected into weak wall site according the preoperative evaluation or intraoperative finding. The balloon was once again introduced into the created cavity and inflated to achieve the PMMA shield (eggshell method). Outcome, PMMA leakage condition, X-ray, and CT were reviewed postoperatively.Results Symptomatic cement extravasation-related complications or leakage on X-ray were not observed in follow-up. Only one adjacent compression fracture has happened in 1 month. Improvement in vertebral height and the mean kyphotic angle was also noted. The mean VAS and ODI decreased significantly from preoperation to postoperation (p< 0.05). The vertebral wall injury score reviews also told us that the eggshell technique is fit for multiple conditions of wall injury.Conclusion It is always concerned for the leakage of PMMA during spine surgery. There are many options of new implant for decreasing the rate of leakage. Greene introduces the eggshell technique since 2007. According to our experiences of kyphoplasty with this eggshell technique, the technique is a safe and significantly functional works for decreasing the leakage of PMMA and pain scale in various wall injury conditions. Disclosure of Interest None declared Reference Greene DL, Isaac R, Neuwirth M, Bitan FD. The eggshell technique for prevention of cement leakage during kyphoplasty. J Spinal Disord Tech 2007;20(3):229–232

In this study, indium tin oxide (ITO) films were deposited on p-type GaP films with a AuBe diffused metal layer to form ohmic contacts. Without the AuBe diffused into p-GaP films, the ITO deposited on p-GaP showed a non-ohmic characteristic. After the AuBe diffused, the ITO deposited on p-GaP displayed a linear current-voltage characteristic and the specific contact resistance showed 2.63 × 10−4Ω cm2. Furthermore, the specific contact resistance could be improved to 1.57 × 10−4Ω cm2when the sample post-annealed at 400°C. The transmittance of ITO film almost was kept at 90% in the wavelength range of 400–700 nm after thermal annealing. These results revealed that the ITO films can be a suitable transparent current spreading layer for the fabrication of AlGaInP-based light-emitting diodes with a AuBe diffused metal layer.

Body-to-body leakage (BBL) current in a partially depleted silicon-on-insulator (PD-SOI) device is increased significantly as polyspacing (PS) is reduced in technology scaling. We found out that the BBL has a great impact to Vt variation. We have demonstrated that the BBL can be minimized drastically by implant optimization. The dependence of the BBL on silicon film thickness, e-SiGe structure, and dopant diffusivity is also discussed in this paper. The layout effect of the BBL current in PD-SOI devices has been characterized with different PSs, device widths, and polylengths. Finally, we have demonstrated that the BBL current can be reduced below junction leakage level.

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