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排序方式: 共有864条查询结果,搜索用时 15 毫秒
1.
In this study, feasibility of membrane separation for the removal of indigenous noroviruses (NVs) is evaluated. The indigenous NV gene was never detected from ultrafiltration (UF) permeates of sewage sludge and treated wastewater. Indigenous NV gene was also not detected from permeates of sewage sludge and treated wastewater by microfiltration (MF) with a pore size of 0.1 microm (MF0.1). Even though the pore size of MF (0.1 microm) was much larger than the diameter of virus particle (approximately 30-40nm), more than 4-log10 reduction value (LRV) at maximum was achieved by membrane separation with MF0.1. NV genes were often detected from permeates of sewage sludge and treated wastewater by MF with a pore size of 0.45 microm (MF0.45), although the maximum log10 reduction values were more than 3.59 for sewage sludge and more than 2.90 for treated wastewater. It is important to verify factors determining the removal efficiency of viruses with MF membranes. 相似文献
2.
In a healthy 49-year-old man, a decrease in job efficiency was noticed along with bizarre behavior. On admission, he was euphoric, childish, superficial and had increased libido. Neurological findings were normal. There were no abnormal findings on routine blood tests, hematochemistry or urine analysis. MRI showed no abnormal findings. However, single photon emission CT (SPECT) showed diffuse hypoaccummulation of tracer from the temporal to frontal regions. Lumbar puncture showed clear cerebrospinal fluid (CSF) with pleocytosis and an elevated protein level. Moreover, antibody IgG titers to herpes simplex virus (HSV) and measles virus were elevated, according to EIA [serum HSV -1,202.2x, measles virus 47.1x: CSF HSV-116.1x, measles virus 9.9x]. The ratio of serum to CSF antibody titers of HSV and measles virus were 12.5 and 4.75, respectively. The antibody index values of HSV and measles virus IgG titers were 8.42 and 22.22. The ratio of albumin was 105.7. Chronic, progressive HSV encephalitis is rare, and there have been very few reports of encephalitis due to double infection by HSV and another virus. Our patient was diagnosed as having encephalitis due to double infection with HSV and measles virus, because the ratio of serum to CSF antibody titers was less than 20 and the antibody index values were over 1.91. Moreover, since the IgG index was elevated and the ratio of albumin was not low, it was suggested that the blood-brain-barrier had not been disrupted, and antibodies were being produced chronically in the medullary cavity. Hyperaccummulation of tracer on SPECT studies has been reported in the early stages of HSV encephalitis. In our case, while CT and MRI showed no abnormal findings, SPECT showed diffuse hypoaccummulation. SPECT appears to be a useful tool in the diagnosis of this disorder. In case of chronic, progressive personality change in middle-aged adults, we must be aware of double virus infection of the brain as a possible causal factor. 相似文献
3.
Decentralized adaptive coordinated control of multiple robot arms without using a force sensor 总被引:1,自引:0,他引:1
Haruhisa Kawasaki Author Vitae Satoshi Ueki Author Vitae Author Vitae 《Automatica》2006,42(3):481-488
This paper presents a distributed adaptive coordinated control method for multiple robot arms grasping a common object. The cases of rigid contact and rolling contact are analyzed. In the proposed controller, the dynamic parameters of both object and robot arms are estimated adaptively. The desired motions of the robot arms are generated by an estimated object reference model. The control method requires only the measurements of the positions and velocities of the object and robot arms, but not the measurements of forces and moments at contact points. The asymptotic convergence of trajectory is proven by the Lyapunov-like Lemma. Experiments involving two robot arms handling a common object are shown. 相似文献
4.
5.
Nobuhiro Kumada Nobuo Ozawa Nobukazu Kinomura Fumio Muto 《Materials Research Bulletin》1985,20(5):583-589
Pyrochlores of A1?xHxTaO3·nH2O (A=Na,K) were prepared under the hydrothermal conditions. The values of x for these compounds were increased from 0.3 to 0.5 for A=Na and from 0.2 to 0.5 for A=K by treatment with the distilled water. The compounds with x<0.5 were decomposed to a mixture of NaTaO3 and Na2Ta4O11 for A=Na, or to a mixture of KTaO3 and a tetragonal tungsten bronze phase, and those with x=0.5 to a single phase of A2Ta4O11 at elevated temperatures. Below the decomposition temperatures, defect pyrochlores with oxygen vacancies, , were produced. They were hygroscopic, and in the case of A=K and x=0.5 the original phase was recovered by leaving in air for several hours. 相似文献
6.
Fumio Negoro 《Knowledge》2003,16(7-8):383-397
The purpose of our study is to build up relationships between requirement and source programs with our originally thought-out rules. When other rules to be derived from these original rules are applied to software development, even a single instruction in a programming language could be determined, and the program would satisfy the requirement. More specifically speaking, these rules will turn into a formula or a prototype of software programs. Hence, when the variables in the requirement are placed in the formula, we can get a required program in an automatic way. 相似文献
7.
Wakabayashi H. Ueki M. Narihiro M. Fukai T. Ikezawa N. Matsuda T. Yoshida K. Takeuchi K. Ochiai Y. Mogami T. Kunio T. 《Electron Devices, IEEE Transactions on》2002,49(1):89-95
Sub-50-nm CMOS devices are investigated using steep halo and shallow source/drain extensions. By using a high-ramp-rate spike annealing (HRR-SA) process and high-dose halo, 45-nm CMOS devices are fabricated with drive currents of 650 and 300 μA/μm for an off current of less than 10 nA/μm at 1.2 V with Toxinv =2.5 nm. For an off current less than 300 nA/μm, 33-nm pMOSFETs have a high drive current of 400 uA/μm. Short-channel effect and reverse short-channel effect are suppressed simultaneously by using the HRR-SA process to activate a source/drain extension (SDE) after forming a deep source/drain (S/D). This process sequence is defined as a reverse-order S/D (R-S/D) formation. By using this formation, 24-nm nMOSFETs are achieved with a high drive current of 800 μA/μm for an off current of less than 300 μA/μm at 1.2 V. This high drive current might be a result of a steep halo structure reducing the spreading resistance of source/drain extensions 相似文献
8.
Fumio Matsumura Masayuki Fujita Masanao Shimizu 《Electrical Engineering in Japan》1991,111(7):117-124
This paper presents the robust control design of a magnetic suspension system for a flexible beam which is a simplified model of an elastic rotor in a magnetic bearing system. To stabilize this magnetic suspension system which is unstable in nature, the Hinfin; control theory is applied for a design of the control system. To apply the Hinfin; control theory, a statespace model of an augmented plant with frequency-weighting functions is constructed. This augmented plant has two inputs which are the exogenous inputs and the control inputs, and two outputs which are the sensor outputs and the regulated outputs. Here we consider the mixed sensitivity problem. The Hinfin; controller is implemented by a digital controller which is able to execute the computations very quickly. For the evaluation of the control performance, several experiments are made. The robustness of the closed-loop system is confirmed by the experimental results. The result of this study is useful for the control design of a magnetic bearing system. 相似文献
9.
Hiroyuki Nishimura Fumio Inoue Akio Nakashiba Testuo Ishikawa 《Polymer Engineering and Science》1994,34(20):1529-1534
Fusion simulation is one of the key techniques in designing and producing electrofusion (EF) joints for gas distribution and in evaluating fusion joint integrity. This paper describes the result of a numerical simulation of a thermal fusion process, using the finite element method. A nonlinear heat transfer computer program was used to obtain the temperature profile of a large electrofusion joint at fusion. The effects of applied voltage, heating time, wire pitch, and ambient temperature were examined for designing a 150-mm EF joint. A method to shorten the cooling time was also investigated. The fusion condition range suitable for a 150-mm EF joint was found to be slightly narrower than that suitable for a 50-mm EF joint. Examination of the effect of wire pitch revealed that if the pitch is extremely large, thermal degradation starts in the resin close to the wire before the fusion-interface strength reaches the maximum value. We have developed a program to simulate the process of closing the gap between the pipe and the joint due to resin expansion and melting after the power is supplied. 相似文献
10.
A case of Waldenstr?m's macroglobulinemia (WM) (IgM-kappa type) associated with acute-onset demyelinating peripheral neuropathy is reported. A 49-year-old woman was admitted to our hospital because of general fatigue and recurrent syncope attacks. She was treated with vincristine, cyclophosphamide, epirubicin and prednisolone. By 10th hospital day, her clinical condition improved and serum viscosity was reduced. However, on the 21st hospital day, she suffered from rapidly progressive writing and gait disturbance. Neurological examination showed muscular atrophy and weakness in the distal part of four extremities. Deep tendon reflexes were diminished. There was no sensory deficit. Cerebrospinal fluid was normal. Anti-myelin associated glycoprotein activity of her serum was negative. Both motor and sensory nerve conduction velocities were markedly decreased. Biopsy of sural nerve revealed marked demyelination and onion bulb formation. There was IgM deposition on myelin sheath. Minimal axonal changes excluded the possibility of vincristine neuropathy. Plasmapheresis improved her symptoms, but nerve conduction velocities remained unchanged. Polyneuropathy associated with WM is usually gradual onset and sensory dominant. In this case, associated neuropathy was acute onset, progressive and motor dominant. This type of neuropathy in patients with WM is very rare. 相似文献