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91.

Background  

Many clinical studies have demonstrated that early postoperative enteral nutrition (EN) improved the postroperative course. Post-pancreaticoduodenectomy (PD), patients tend to suffer from postoperative nausea, abdominal distention, and diarrhoea, causing difficulty in the introduction of EN. In this pilot study, we investigated the appropriate nutritional mode post-pancreatic surgery.  相似文献   
92.
A Nb3Sn composite conductor with ≈ 10 000 submicron diameter filaments has been manufactured using the external diffusion process. A.c. losses were greatly reduced by the use of a fine filament size (0.53 μm, design value), a tight twist pitch (0.87 mm) and a small wire diameter (0.153 mm) with a bronze matrix. In an a.c. field with a frequency of 50 Hz and amplitude of 2.0 T, the hysteresis loss and the coupling current loss were observed to be 465 kW m−3 and 26 kW m−3, respectively. A triplex conductor was constructed by cabling three strands at a twisting pitch of 3 mm, and a small coil was wound from this cable (i.d. 11 mm, o.d. 33 mm, axial length 19 mm). With d.c. the coil generated a field of 1.3 T at the critical current, lc of 37.4 A. When the coil was operated at 50 Hz, with an exciting current of Ic, the observed loss averaged over the windings was 240 kW m−3. The quenching current for 50 Hz operation was 53 A at a maximum field of 1.8 T. This was considerably higher than the critical values under d.c. conditions. Preliminary studies have shown that, if this conductor is used in superconducting armature windings of rotating machines, economical benefits are obtained compared with the use of conventional armatures.  相似文献   
93.
New experimental data on the density and viscosity of linear, unbranched perfluoropolyethers are presented at temperatures from 273 to 333 K and pressures up to 180 MPa. The measurements were carried out by a high-pressure burrette apparatus and a falling-cylinder viscometer. The uncertainties of the measurements are estimated to be less than 0.09% for the specific volume and 2.5% for the viscosity. The P-V data at each temperature are correlated satisfactorily by the Tait equation. The viscosity data are also analyzed and correlated with pressure or molar volume by several empirical and theoretical equations.  相似文献   
94.
The activation of 3,5-dinitrobenzoic acid (3,5-DNBA) in situ is proposed for electrocatalytic detection of NADH at low overpotentials. Thus, 3,5-DNBA was strategically connected to a nanostructured surface based on MWCNTs and PEI (an amine rich polymer). Then, R–NO/R–NHOH was electrogenerated in situ by cycling the potential between 0.15 and −0.55 V versus SCE. The formation of an intermediate charge transfer complex is proposed for the reaction between NADH and redox mediator. The apparent Michaelis–Menten constant (KM) obtained by RDE voltammetry and amperometry was in good agreement, around 10−5 mol L−1. The kobs for the catalytic reaction evaluated by chronoamperometry and RDE voltammetry, was in good agreement and was found to be around 104 L mol−1 s−1. The sensor provides a linear response range for NADH from 4.0 up to 42.0 μmol L−1 with a sensitivity of 71 nA L μmol−1, detection and quantification limits of 1.2 and 4.0 μmol L−1 respectively, with a response time of 0.16 s.  相似文献   
95.
This report analyses the results of the human error classification scheme of CREAM applied to organisation-committed human errors related to six departments. These human errors were not caused by the tasks spotlighted by CREAM, but were concentrated on managerial or administrative tasks, so that the authors have corrected and analysed the definitions and links of cause–effect relations related to the large organisation by means of an extended method of CREAM. Considering human errors on the basis of these analyses, findings have allowed the authors to come up with effective relations between organisation-related causal factors and person-related ones. This has demonstrated that organisation-caused human errors are sufficiently analysable by means of the extended method of CREAM.  相似文献   
96.
In a distribution system containing a step voltage regulator (SVR), the maximum capacity of distributed generators (DGs) is calculated for DGs completely dispersed on a distribution line. The maximum capacity of the DGs is calculated under the constraint of an upper or lower voltage regulation value and an allowable current value by using voltage and current profiles expressed analytically in terms of our proposed power density model. As the voltage control method for the SVRs, we consider the conventional SVR, whose transformation ratio is fixed to 1 if it detects reverse power flow, and a reverse power flow SVR which operates appropriately even if it detects reverse power flow. Calculation of the maximum capacity of DGs with respect to the power factor of the DGs indicates which parameters, including the power factor of the DGs, the distribution of the DGs, and the load, influence the maximum DG capacity. Calculation of the maximum capacity of DGs versus the system length indicates that the constraints can be subdivided into two modes in the conventional SVR and four modes in the reverse power flow SVR. The maximum DG capacity in the system with a reverse power flow SVR is larger than that in a system with the conventional SVR. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 41–51, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20591  相似文献   
97.
The respective volumes of hepatic tumors and nontumorous parenchyma of 50 patients requiring hepatectomy of more than one segment of Healey for tumor removal were measured using computed tomography (Vol-CT). The volume estimated by Vol-CT was found to correlate with the real weight resected (P < .0001) with a mean absolute error of 64.9 mL. The ratio of the nontumorous parenchymal volume of the resected liver to that of the whole liver (R2) in 15 patients who underwent right or extended right hepatic lobectomy was 43% +/- 15%. Eight of 15 patients with R2s < 60% underwent the procedures without right portal vein embolization (PE). The other seven with R2s exceeding 60% or an indocyanine green retention rate after 15 minutes (ICG15) of 10% to 20% underwent PE: in six of seven, the nontumorous parenchyma of the right hepatic lobe became atrophic and in all seven, the volume of the remaining left hepatic lobe increased with a decrease in the mean R2 from 62% +/- 14% to 55% +/- 8% (P = .0006). In the remaining 35 who underwent other hepatectomy procedures, R2s also remained <60%. Overall, at surgery, in 27 with normal liver function (ICG15 < 10%), R2s exceeded 60% in one, remained at 50% to 60% in five, and <50% in 21, whereas 23 patients except for one with an ICG15 exceeding 10%, had R2s of <50%. The postoperative serum total bilirubin levels in 84% of the patients remained within the normal range and there was no surgery-related mortality. In conclusion, 1) Vol-CT can accurately assess the extent of liver resection, 2) individuals with normal liver function can undergo resection of up to 60% of the nontumorous parenchyma without the need for PE, and 3) PE can be used to reduce the size of the resected tissue and increase the volume of the remnant liver to approximate the target limits in individuals with large tumors or minimally abnormal liver function.  相似文献   
98.
99.
Far-infra-red photoconductivity measurements are used to study residual shallow donor species in InP bulk crystals grown by the synthesis, solute-diffusion technique. The observation of 1s-2p, m =+ 1 Zeeman transitions between the shallow donor-impurity states reveals that two dominant residual donors are included in the InP bulk crystals having carrier concentrations of less than 1 × 1015 cm?3 The donors are tentatively identified as Si and S.  相似文献   
100.
Diffusion kinetics of three dyes in nematic liquid crystals are studied with single-molecule fluorescence autocorrelation spectroscopy. Markedly large anisotropy was observed in the diffusion coefficient and structure of diffusion molecules showed no marked effect on the anisotropy.  相似文献   
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