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Background: Maternal hypotension is a common complication during cesarean section performed under spinal anesthesia. Changes in maternal heart rate with postural changes or values of heart rate variability have been reported to predict hypotension. Therefore, we hypothesized that changes in heart rate variability due to postural changes can predict hypotension.Methods: A total of 45 women scheduled to undergo cesarean section under spinal anesthesia were enrolled. A postural change test was performed the day before cesarean section. The ratio of the power of low and high frequency components contributing to heart rate variability was assessed in the order of supine, left lateral, and supine. Patients who exhibited a ⩾two-fold increase in the low-to-high frequency ratio when moving to supine from the lateral position were assigned to the postural change test-positive group.Results: According to the findings of the postural change test, patients were assigned to the positive (n=22) and negative (n=23) groups, respectively. Hypotension occurred in 35/45 patients, of whom 21 (60%) were in the positive group and 14 (40%) were in the negative group. The incidence of hypotension was greater in the positive group (P<0.01). The total dose of ephedrine was greater in the positive group (15±11 vs. 7±7mg, P=0.005). The area under the receiver operating characteristic curve was 0.76 for the postural change test as a predictor of hypotension.Conclusion: The postural change test with heart rate variability analysis may be used to predict the risk of hypotension during spinal anesthesia for cesarean section. [ABSTRACT FROM AUTHOR]

This paper reports on a bilateral comparison of millimeter-wave attenuation in WR-15 waveguide band between the National Metrology Institute of Japan (NMIJ) and the National Metrology Centre, A∗STAR (NMC). Different types of attenuation measurement systems were independently developed at both laboratories. The systems are based on a stabilized single-channel intermediate frequency (IF) substitution method at NMIJ, and a dual-channel audio frequency substitution method at NMC. A comparison was carried out at 50 GHz and 54 GHz using a programmable step attenuator fitted with precision coaxial to waveguide adaptors as a traveling standard. Good agreement of the measurement results between both laboratories was verified in the attenuation range up to 60 dB. [ABSTRACT FROM AUTHOR]

Abstract: Crystalline silicon solar cells with high ohmic emitters show higher efficiencies due to a better blue response. Unfortunately, the only way to contact them by screen printing is using the selective emitter technology. This study shows that contacting emitters with Rsh = 100Ω/sq can be achieved by standard screen printing technology without selective emitter processing thanks to the development of a new silver paste. Thus, no additional process steps are needed to selectively dope the emitter. We study the electrical properties of industrially processed c-Si solar cells, with two different screen printing silver pastes (Pastes A and B) and emitters with sheet resistances Rsh = 80Ω/sq, 100Ω/sq, and laser doped selective emitter with Rsh = 20Ω/sq on Rsh = 100Ω/sq. On the solar cells with 80Ω/sq emitter, paste B yields a low series resistance Rs = 0.72Ω cm2, thanks to its lower contact resistance ρc and its lower penetration into the space charge region, compared to paste A. The low series resistance leads to an efficiency gain Δη = 0.7%abs. We also obtain promising results on 100Ω/sq, as the contact resistance ρc ≤ 3.1 mΩcm2 leads to a maximum fill factor FF = 78.8%. The efficiency η = 18.3% of the 100Ω/sq emitter solar cells is then comparable to the one of the selective emitter cells. With paste B, we demonstrate that it is now possible to contact high ohmic emitters, without the use of a selective emitter structure. [Copyright &y& Elsevier]

Abstract: We present a macroscopic and microscopic analysis of the contact formation of two different commercially available silver screen printing pastes (A and B) for contacting lowly doped phosphorus emitters on crystalline silicon solar cells. The new paste B shows lower contact resistance than paste A on conventional emitters of sheet resistances Rsh = 60w/sq and 100w/sq as well as for selective emitters with Rsh,se = 20w/sq. Paste B achieves a contact resistance ρc = 3mwcm2 on high ohmic emitters with Rsh = 100w/sq. Initial investigations demonstrate different contact formations for the two pastes. Paste B shows a higher density of silver crystallites grown in the silicon emitter compared to paste A for the lowly doped emitter with Rsh = 100w/sq. Additionally, the glass layer at the interface between the front grid of paste B and the investigated emitters contains a high density of silver colloids. The high density of Ag-crystallites and Ag-colloids, the weaker glass frits aggressivity, as well as the different formation of glass layer accompany the better contacting features of paste B on high ohmic emitters. [Copyright &y& Elsevier]

Abstract: Background: Liver fibrosis is the main predictor of the progression of nonalcoholic fatty liver disease. Transient elastography (FibroScan), which measures liver stiffness, is a novel, noninvasive method to assess liver fibrosis. Aim: We investigated the usefulness of liver stiffness measurement in the evaluation of liver fibrosis in nonalcoholic fatty liver disease patients. Study population: A total of 97 nonalcoholic fatty liver disease patients. Methods: Transient elastography was performed for liver stiffness measurement in 97 nonalcoholic fatty liver disease patients. And the relationship between histological parameters and liver stiffness measurement was studied by multivariate analysis. Moreover, we investigated the relationship between liver stiffness measurement and the serum levels of hyaluronic acid and type IV collagen 7s domain. Results: The liver stiffness was well correlated with the stage of liver fibrosis (Kruskal–Wallis test p <0.0001). The areas under the receiver-operating characteristic curves were 0.927 for ≥F1, 0.865 for ≥F2, 0.904 for ≥F3, 0.991 for ≥F4. Only fibrosis stage was correlated significantly with liver stiffness measurement by multiple regression analysis. Liver stiffness was also strongly correlated with the serum levels of type IV collagen 7s domain (r =0.525, p <0.0001) and hyaluronic acid (r =0.457, p <0.0001). Conclusions: Our results show a significant correlation between liver stiffness measurement and fibrosis stage in nonalcoholic fatty liver disease patients, as confirmed by the results of liver biopsy, which remains the gold standard for evaluation of the severity of liver fibrosis in patients with nonalcoholic steatohepatitis. [Copyright &y& Elsevier]

BACKGROUND: The rates of spontaneous remission and relapse of autoimmune pancreatitis (AIP) are not known. OBJECTIVE: To study the clinicopathologic factors predictive of remission and relapse in cases of AIP. DESIGN: Retrospective study. PATIENTS: Of the 20 patients with AIP, complete response to steroid therapy was recognized in 12 patients, and the remaining 8 patients improved without steroid therapy. Seven patients experienced a relapse. RESULTS: Patients who were seronegative for immunoglobulin (Ig) G4, had no obstructive jaundice, no diabetes mellitus, no swelling of the duodenal papilla, negative staining of the duodenal papilla for IgG4, and focal pancreatic swelling showed a greater tendency toward spontaneous remission (P < .05). The results of multivariate analysis revealed that negative staining of the duodenal papilla for IgG4 was the only independent predictor of spontaneous remission of AIP (odds ratio [OR] 1.395, P = .0304). Seropositivity for IgG4, diffuse swelling of the pancreas, and the presence of stricture in the lower part of the bile duct were significantly associated with a relapse of AIP (P < .05) according to the results of univariate analysis, whereas the results of multivariate analysis revealed only diffuse pancreatic swelling as an independent predictor of a relapse of AIP (OR 26.197, P = .0331). CONCLUSIONS: Endoscopic findings are of useful prognostic value, because patients with AIP and with negative staining of the duodenal papilla for IgG4 appeared to have a higher frequency of remission without steroid therapy. Patients with AIP and with diffuse pancreatic swelling were found to be at an increased risk of relapse after the initial steroid administration. [ABSTRACT FROM AUTHOR]

This chapter describes a brief overview of present advances and challenges in PET methodology from the engineering side. Topics are as follows: (1) advances in hardware design and sophisticated software development for registering PET and anatomical images, (2) higher spatial resolution approaching sub-millimeters, (3) improved temporal resolution, (4) repeat assessment of physiologic functions, (5) corrections for partial volume effect (PVE), and (6) motion correction capability. These features provide potentials of using PET in new application fields. [Copyright &y& Elsevier]

Abstract: Atmospheric deposition is an important removal process of aerosol particles and gases from the atmosphere. To elucidate the relative contributions of wet and dry processes and in-cloud and below-cloud scavenging based on deposition amounts in winter at Mt. Tateyama, central Japan, we obtained daily samples (December, 2006–March, 2007) of size-segregated aerosol particles and precipitation at Senjyugahara (SJ; 475 m a.s.l.) and vertical samples of spring snow cover at Murododaira (MR, 2450 m a.s.l., 13 km distance from SJ) on the western flank of Mt. Tateyama. The NH4 + and nssSO4 2− in aerosols were mostly found in the fine fraction (<2 μm), although Na+, NO3 −, and nssCa2+ were mainly detected in the coarse fraction (>2 μm). Average ionic concentrations (μg g−1) in precipitation at SJ were higher about 3.8 for Na+ and nssCa2+, 3.4 for NO3 −, 3.7 for NH4 +, 2.5 for nssSO4 2− than those at MR, whereas cumulative precipitation amounts at SJ and MR were, respectively, 84 and 175 cm of water equivalent. Wet and dry deposition amounts during the study period were estimated for sites using size-segregated aerosol data, winter averages of HNO3, NH3, and SO2 concentrations, and dry deposition velocities. Particle-dry deposition comprised about 3% (Na+) to 11% (NH4 +) of the total deposition at MR. The maximum amounts of gas dry deposition were estimated, respectively, as 4, 13, and 3% of the total deposition at MR for NH4 +, NO3 −, and nssSO4 2−. The relative contributions of below-cloud scavenging (BCS) between MR and SJ were estimated as considering the wet only deposition amount at MR. Higher contributions of BCS were obtained for Na+ (56%) and nssCa2+ (45%), whereas BCSs for NH4 +, NO3 −, and nssSO4 2− were lower than 28%. Ionic constituents existing predominantly in the coarse fraction showed a large contribution of BCS. [Copyright &y& Elsevier]

Oxygen-15 can be roduced using a relatively small cyclotron emitting a deuteron beam with the approximate energy of 3 MeV. However, the neutron emission from the cyclotron itself requires a large scale of shield, causing the total size of the system difficult to be placed at clinical department. We have evaluated a novel idea to reduce the neutron roduction from the cyclotron to a negligible level, and examined if it is applicable to a clinical environment. Systematic physics experiments were carried out using a Tandem Van de Graaff accelerator to validate the feasibility of our approach, in which the neutron production was assessed for realistic energy ranges of deuteron. It was shown that neutron production was reduced dramatically by a factor of 10 to the fourth using our approach, whilst enough amount of oxygen-15 was roduced. This study suggested that a small oxygen-15 generator is possible which could be laced next to existing clinical PET cameras. [Copyright &y& Elsevier]

Recipients of allogeneic hematopoietic stem cell transplant had a significantly higher risk of developing secondary solid cancers than the general population. Risk of developing oral/pharynx or esophageal cancer continued to increase with time after transplant. Extensive-type chronic graft-versus-host disease and older age were a significant risk factor for developing secondary solid cancers.Background The number of long-term survivors after hematopoietic stem cell transplantation (HSCT) showed steady increase in the past two decades. Second malignancies after HSCT are a devastating late complication. We analyzed the incidence of, risk compared with that in the general population, and risk factors for secondary solid cancers. Patients and methods Patients were 17 545 adult recipients of a first allogeneic stem cell transplantation between 1990 and 2007 in Japan. Risks of developing secondary solid tumors were compared with general population by using standard incidence ratios (SIRs). Results Two-hundred sixty-nine secondary solid cancers were identified. The cumulative incidence was 0.7% [95% confidence interval (CI), 0.6%–0.9%] at 5 years and 1.7% (95% CI, 1.4%–1.9%) at 10 years after transplant. The risk was significantly higher than that in the general population (SIR = 1.8, 95% CI, 1.5–2.0). Risk was higher for oral cancer (SIR = 15.7, 95% CI, 12.1–20.1), esophageal cancer (SIR = 8.5, 95% CI, 6.1–11.5), colon cancer (SIR = 1.9, 95% CI, 1.2–2.7), skin cancer (SIR = 7.2, 95% CI, 3.9–12.4), and brain/nervous system cancer (SIR = 4.1, 95% CI, 1.6–8.4). The risk of developing oral, esophageal, or skin cancer was higher at all times after 1-year post-transplant. Extensive-type chronic graft-versus-host disease (GVHD) was a significant risk factor for the development of all solid tumors (RR = 1.8, P < 0.001), as well as for oral (RR = 2.9, P < 0.001) and esophageal (RR = 5.3, P < 0.001) cancers. Limited-type chronic GVHD was an independent risk factor for skin cancers (RR = 5.8, P = 0.016). Conclusion Recipients of allogeneic HSCT had a significantly higher ∼2-fold risk of developing secondary solid cancers than the general population. Lifelong screening for high-risk organ sites, especially oral or esophageal cancers, is important for recipients with active, or a history of, chronic GVHD. [ABSTRACT FROM AUTHOR]

Background We aimed to clarify the impact of the donor source of allogeneic stem cell transplantation (allo-SCT) on Philadelphia chromosome-negative acute lymphoblastic leukemia [Ph(−) ALL] with focus on cord blood (CB). Patients and methods We retrospectively analyzed data of 1726 patients who underwent myeloablative allo-SCT for adult Ph(−) ALL. The sources of the allo-SCT were related donors (RD; N = 684), unrelated donors (URD; N = 809), and CB (N = 233). Results Overall survival (OS) in patients after CB allo-SCT in first complete remission (CR1) was comparable with that after RD or URD allo-SCT (RD: 65%, URD: 64% and CB: 57% at 4 years, P = 0.11). CB was not a significant risk factor for relapse or non-relapse mortality as well as for OS in multivariate analyses. Similarly, the donor source was not a significant risk factor for OS in subsequent CR or non-CR (RD: 47%, URD: 39% and CB: 48% in subsequent CR, P = 0.33; RD: 15%, URD: 21% and CB: 18% in non-CR, P = 0.20 at 4 years). Conclusion Allo-SCT using CB led to OS similar to those of RD or URD in any disease status. To avoid missing the appropriate timing, CB is a favorable alternative source for adult Ph(−) ALL patients without a suitable RD or URD. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To test if simple motor imagery, like thumb abduction, preferentially influences the excitability of the spinal or cortical motoneurons. Methods: Ten healthy subjects underwent two separate experiments, each consisting of recording F waves and MEPs from abductor pollicis brevis (APB) in three consecutive sessions: (1) baseline, (2) after immobilizing APB for 3h, and (3) after brief muscle exercise. During the immobilization, the subjects were instructed to volitionally relax APB in experiment 1 (relaxation task), and mentally simulate thumb abduction without actual movement in experiment 2 (imagery task). Results: Relaxation task suppressed both MEPs and F waves. Motor imagery reduced this suppression, restoring F waves nearly completely (94%) and MEPs only partially (77%). Hence, the rest-induced decline of MEPs in part results from cortical modulation. In contrast, statistical analysis revealed no differences in imagery-induced recovery of motoneuron excitabilities whether assessed by F wave or MEP. Thus, increased excitability of spinal motoneurons responsible for F-wave changes also accounts for recovery of MEPs. Conclusions: Volitional relaxation depresses the spinal and cortical motoneurons, whereas mental simulation counters rest-induced suppression primarily by restoring spinal excitability. Significance: The present findings help elucidate physiologic mechanisms underlying motor imagery. [Copyright &y& Elsevier]

Abstract: This study aims at determining the applicability of a segment weight dynamic movement (SWDM) method as an alternative for normalizing gait EMGs in comparison with the conventional isometric maximal voluntary contraction (MVC) method. The SWDM method employs reference exercises, each being a dynamic, repetitive movement of a joint under the load of the segment weight (i.e., the total weight of all segments distal to the joint). EMG amplitudes of 28 healthy male subjects walking at 120steps/min were normalized by the two methods. CV and VR were used to assess the inter-individual variability of both the normalized gait EMG for 8 muscles. The CV and VR values attained with the two methods were close to each other, as well as to those obtained by other researchers using the isometric MVC method. These results suggest that the SWDM method has a comparable level of applicability to gait EMG normalization as the isometric MVC method. [Copyright &y& Elsevier]

The electronic structure of the silver chalcogenide compound Ag2S has been investigated, experimentally using photoelectron spectroscopy, and theoretically using the full-potential LMTO calculation. The photoemission data taken using a synchrotron photon source is compared with the calculated valence density of states (DOS). The band structure is also calculated for the high-temperature cubic disorder phase. For that sake, a hypothetical ordered structure model is utilized instead of the disorder structure. From the hitherto reported crystallographic data and the calculated total energies, microscopic mechanisms of the phase transition and superionic conduction are discussed. [Copyright &y& Elsevier]