Existing phenol production processes tend to be energy-consuming and produce unwanted by-products. We report an efficient process using a shell-and-tube reactor, in which a gaseous mixture of benzene and oxygen is fed into a porous alumina tube coated with a palladium thin layer and hydrogen is fed into the shell. Hydrogen dissociated on the palladium layer surface permeates onto the back and reacts with oxygen to give active oxygen species, which attack benzene to produce phenol. This one-step process attained phenol formation selectivities of 80 to 97% at benzene conversions of 2 to 16% below 250 degrees C (phenol yield: 1.5 kilograms per kilogram of catalyst per hour at 150 degrees C).

The isolated contributions of motor unit recruitment and firing rate variations to the median frequency of the electromyogram's power density spectrum were determined. Orderly stimulation of the cat gastrocnemius motor units via nerve electrodes gave rise to linearly increasing median frequency regardless of the action potential firing rate of the active motor units. Increase in the discharge rate of all the motor units resulted in nearly constant median frequency. It was concluded that the increasing average conduction velocity during motor unit recruitment is the major contributor to variations in the electromyogram median frequency. The possibility of using the median frequency as the index to identify the recruitment control strategies employed by various muscles during increasing force contraction is suggested.

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Objective Epstein-Barr virus (EBV), a lymphotropic herpes virus causing infectious mononucleosis (IM), also causes various central nervous system (CNS) infections. In the present study, EBVCNSinfections were investigated.Patients and Methods For adult inpatients in our hospital and related hospitals between 1984-2002, CNS syndromes with IM symptomswere examined, and serologic positives were assessed according to established criteria.Polymerase chain reaction (PCR) was performed for cerebrospinal fluid (CSF) from seven patients. ResultsTen patients with EBV-related CNS infections were found; their mean age was 36 years (20-79 years). The neurologic forms were as follows: acute encephalitis (4 patients), acute cerebellar ataxia (1), acute disseminated encephalomyelitis (ADEM) (2), myelitis (1), and meningitis (2). The PCR from CSF was positive in two patients with meningitis, one patient with ADEM, and one patient with encephalitis-associated chronic EVB infection. One case of encephalitis and another of relapsing ADEMwere attributed to chronic EBVinfection. Conclusion Our study identified a variety of EBVrelated CNS infections. EBVCNS infections are divided into two groups: 1) CNSsyndromes associated with primary EBVor reactivated infection, and 2) those associated with chronic EBVinfection; it is notable that in the former, diverse CNSsyndromes including ADEM can occur, whereas in the latter, chronic or recurrent CNS syndromes are produced. (Internal Medicine 42: 33-40, 2003)

Herpes simplex virus (HSV) myelitis has previously been reported to be a form of acute ascending necrotizing myelitis caused by HSV type 2 (HSV-2). We studied neurological symptoms, clinical course, magnetic resonance imaging (MRI) findings, and diagnosis by polymerase chain reaction (PCR) methods in 9 patients with HSV myelitis. In 6 cases, disease onset was marked by sensorimotor disturbances of lower extremities and urinary disturbances, with the transverse myelopathy gradually ascending to the cervicothoracic spinal cord level. The other 3 cases showed transverse myelopathy without an ascending pattern. Six cases showed acute progression, while 3 cases showed a subacute course. There were 2 cases with recurrent episodes. Three patients recovered, however, in the remaining 6 patients severe sequelae such as paraplegia persisted despite antiviral therapy. MRI showed a hyperintense lesion on T2-weighted images. Gadolinium enhancement was observed in 2 cases, and 1 case showed a hyperintense lesion both on T1- and on T2-weighted images, suggesting hemorrhagic necrosis. HSV-2 was detected by PCR techniques in all 6 cases with an ascending pattern. HSV-1 DNA was detected in 2 and HSV-2 DNA in 1 of the 3 cases with a nonascending pattern. Our findings demonstrate diverse clinical manifestations of HSV myelitis.

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