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The incidence of surgical site infection (SSI) is higher in spinal surgeries than in general orthopedic operations. In this study, we aimed to develop a scoring system with reduced health care costs for detecting spinal surgery patients at high risk for SSI.
Design:
Retrospective cohort study.
Patients:
In total, 824 patients who underwent spinal surgery at 2 university hospitals from September 2005 to May 2011.
Methods:
We reviewed the medical records of 824 patients, and we examined 19 risk factors to identify high-risk patients. After narrowing down the variables by univariate analysis, multiple logistic analysis was performed for factors with P values <.2, using SSI as a dependent variable. Only factors that showed P values <.05 were included in the final models, and each factor was scored based on the β coefficient values obtained. The clinical prediction rules were thereby prepared.
Results:
“Emergency operation,” “blood loss >400 mL,” “presence of diabetes,” “presence of skin disease,” and “total serum albumin value <3.2 g/dL” were detected by multivariable modeling and were incorporated into the risk scores. Applying these 5 independent predictive factors, we were able to predict the infection incidence after spinal surgery.
Conclusions:
Our present study could aid physicians in making decisions regarding prevention strategies in patients undergoing spinal surgery. Stratification of risks employing this scoring system will facilitate the identification of patients most likely to benefit from complex, time-consuming and expensive infection prevention strategies, thereby possibly reducing healthcare costs.
The consumption of probiotics by pregnant and lactating women may prevent the onset of allergic disorders in their children by increasing the concentrations of immunoactive agents such as cytokines in breast milk. Prebiotics such as fructo-oligosaccharides (FOS) increase the number of beneficial organisms such as bifidobacteria. Thus, prebiotics may have an effect similar to that of probiotics. The objective of the present study was to carry out a comprehensive analysis of mRNA expression in human milk cells to identify changes in the concentrations of cytokines in breast milk after the consumption of FOS (4 g × 2 times/d) by pregnant and lactating women. The microarray analysis of human milk cells demonstrated that the expression levels of five genes in colostrum samples and fourteen genes in 1-month breast milk samples differed more than 3-fold between the FOS and control groups (sucrose group). The mRNA expression level of IL-27, a cytokine associated with immunoregulatory function, was significantly higher in 1-month breast milk samples obtained from the FOS group than in those obtained from the control group. In addition, the protein concentrations of IL-27 in colostrum and 1-month breast milk samples were significantly higher in the FOS group than in the control group. In conclusion, the consumption of FOS by pregnant and lactating women increases the production of IL-27 in breast milk. Future studies will address the association of this phenomenon with the onset of allergic disorders in children.
This paper presents novel 3D heterogeneous integrations using MEMS Devices for RF applications. We propose a 3D heterogeneous integration method that combines the advantages of LTCC, passive integration, and MEMS technologies. The basic concept is to form a large-size LTCC wiring wafer and then to form high-Q passives or MEMS filters directly on the wafer surface. Other functional devices such as ICs, SAWs, and MEMS switches are mounted above the surface-formed devices. A miniaturized duplexer consisted of IPD, SAW, and film bulk acoustic resonator (FBAR); and a next generation duplexer module consisted of an MEMS tunable filter and a piezoelectric transducer (PZT)-actuated RF MEMS switch were constructed to demonstrate its feasibility and effectiveness.
The unrestricted T-system is a family of relations in the Grothendieck ring of the category of the finite-dimensional modules of Yangian or quantum affine algebra associated with a complex simple Lie algebra. The unrestricted T-system admits a reduction called the restricted T-system. In this paper we formulate the periodicity conjecture for the restricted T-systems, which is the counterpart of the known and partially proved periodicity conjecture for the restricted Y-systems. Then, we partially prove the conjecture by various methods: the cluster algebra and cluster category method for the simply laced case, the determinant method for types A and C, and the direct method for types A, D, and B (level 2).
Spatially growing mixing layers are simulated numerically using a two-dimensional vortex method. Special attention is paid to the effect of double-frequency forcing on the development of a mixing layer. Two different types of forcing are considered: superposition of a fundamental frequency (F) on one of its subharmonics (Case I), and superposition of two frequencies of a resonance type, F ± ΔF (Case II). The effects of forcing amplitude and relative phase shift between the two forcing frequencies are also examined. Instantaneous plots of discrete vortices and various statistics up to the second-order moment are obtained to see the variation of coherent structures. Results show that the number of merging vortices and thus the growth of a mixing layer can be effectively controlled by double-frequency forcing if forcing frequencies, phase shifts and forcing amplitudes are suitably selected.
This paper aims to elucidate the structure of the turbulent mixing layers, especially, its dependence on initial disturbances. The mixing layers are produced by setting a woven-wire screen perpendicular to the freestream in the test section of a wind tunnel to obstruct part of the flow. Three kinds of model geometry are treated; these model screens produced mixing layers which may be regarded as the equivalents of the plane mixing layer and of two-dimensional and axisymmetric wakes issuing into ambient streams of higher velocity. The initial disturbances are imposed by installing thin rods of various sizes along the edge of the screen or at the origin of the mixing layer. Flow features are visualized by the smoke-wire method. Statistical quantities are measured by a laser-Doppler velocimeter. In all cases large-scale transverse vortices seem to persist, although comparatively small-scale vortices are superimposed on the flow field in the mixing layer. The mixing layers are in self-preserving state at least up to third-order moments, but the self-preserving state is different in each case. The growth rates of the mixing layer are shown to depend strongly on the initial disturbance imposed.
In the diagnosis, treatment, and care of dementia patients in the senile stage, comprehensive evaluation of ability in daily life and mental function is needed. Using a simple behavioral rating scale for the mental states (NM scale) and activities of daily living (N-ADL) of the elderly, we evaluated 250 elderly subjects. According to the NM scale, the scores for subjects in whom the severity was clinically diagnosed were as follows: normal, 50–48; borderline, 47–43; mild dementia, 42–31; moderate dementia, 30–17; and severe dementia, 16–0. Screening for dementia and determining its severity were readily accomplished using the NM scale, and basic activities in the daily life of the elderly could be evaluated effectively using the N-ADL. There was a significant correlation (r=0.863) between the Hasegawa dementia scale and the NM scale (p<0.001), a significant correlation (r=−0.947) between intellectual function scores of the GBS scale and the NM scale, and a significant correlation (r=0.944) between motor function score of the GBS scale and the N-ADL score. Evaluations of daily life activities can be made not only by psychiatrists and clinical psychologists, but by nonspecialists as well, because they are based on data obtained by observation of daily life behaviors; thus, assessment is appropriate both in clinical settings and in places of living.
The sound generated by a circular cylinder in a flow at low Mach numbers is investigated by direct solution of the two-dimensional unsteady compressible Navier–Stokes equations. Results show that sound pressure waves are generated primarily by vortex shedding from the cylinder surface into its wake. When a vortex is shed from one side of the cylinder, a negative pressure pulse is generated from that side whereas a positive pressure pulse is generated from the other side; alternate vortex shedding from the upper and lower sides of the cylinder produces negative and positive pulses alternately and thus produces sound pressure waves on both sides. The dipolar nature of the generated sound is confirmed; lift dipole dominates the sound field. The Doppler effect is shown to play an important role at finite Mach numbers. The direct solutions are also compared with the solutions obtained by Curle's acoustic analogy. The results show that Curle's solution describes well not only the generation mechanism of the sound but also the propagation process if we take the Doppler effect into consideration.
In order to investigate the genesis of powerful radio jet, we have mapped the central 10 pc region of the nearby radio galaxy NGC 6251 with a 0.2 pc resolution using VLBI at two radio frequencies, 5 GHz and 15 GHz, we have found the sub-parsec-scale counterjet for the first time in this radio galaxy. This discovery allows us to investigate the jet acceleration based on the relativistic beaming model.
One of the most common methods for obtaining water repellent surfaces is spreading fluoropolymer or fluoroalkylsilane onto substrates. However, this method is not applicable to low heat-resistant substrates such as plastics, since after spreading, the method requires a heating process which is generally conducted at a temperature of about 600K. The objective of this study is the preparation of ultra water-repellent and optically transparent thin films at low temperatures below 373K. The films were deposited by means of microwave plasma enhanced plasma chemical vapor deposition (MPECVD) using organosilane, that is, trimethylmethoxysilane (TMMOS) as a source with adding Ar, CO2, N2, O2 or air as an excitation gas. Under optimized preparation conditions, films with water contact angles more than 150 degrees and optical transparencies more than 90% were successfully fabricated.
Two-dimensional, unsteady, compressible flow fields produced by the interactions between a single vortex or a pair of vortices and a shock wave are simulated numerically. The Navier–Stokes equations are solved by a finite difference method. The sixth-order-accurate compact Padé scheme is used for spatial derivatives, together with the fourth-order-accurate Runge–Kutta scheme for time integration. The detailed mechanics of the flow fields at an early stage of the interactions and the basic nature of the near-field sound generated by the interactions are studied. The results for both a single vortex and a pair of vortices suggest that the generation and the nature of sounds are closely related to the generation of reflected shock waves. The flow field differs significantly when the pair of vortices moves in the same direction as the shock wave than when opposite to it.
Millimeter-wave continuum sources in NGC 7538 region were observed with the NRO 45-m telescope and Nobeyama Millimeter Array. NRO 45-m telescope observations showed that the compact region which includes IRS1, IRS2, and IRS3 has a strong millimeter-wave intensity excess, cf. figures 1, and 2.
Chemical compositions of superconductors of Bi1−xPbxSrCaCu1.8Oy (x = 0.1, 0.3, and 0.5) were investigated by analytical electron microscopy (AEM) supplemented by electron microprobe analysis. Samples were prepared by a solid state reaction method under oxygen partial pressures of 0.20 and 0.077 atm. The high-Tc phase appeared only in the samples of Bi1−xPbxSrCaCu1.8Oy (x = 0.1 and 0.3) prepared under an oxygen partial pressure of 0.077 atm. In the samples containing the high-Tc phase, stacking structures of 2, 3, and 4 perovskite layers were observed by transmission electron microscopy (TEM). From AEM analysis, it was shown that in order to make the high-Tc phase, the substitution ratio of Pb for Bi was about 0.2.
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