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Harmonious voluntary movements require efficiency in their planning and execution. Throughout middle childhood structural changes in the central nervous and musculoskeletal systems influence these processes and resultant motor behavior. In this study, we evaluated the characteristics of the motor planning and executing of aiming movements directed at targets located in different positions in space in children aged 7, 9, and 11 years. We divided 43 right-handed children, into three age groups and instructed them to perform aiming movements directed at targets using a stylus on a digital tablet. The children performed the movement with their dominant upper limbs from a starting point towards targets positioned ipsilaterally or contralaterally to this dominant limb. We analyzed temporal and spatial variables of motor performance. Younger (7-year-old) children made more errors in the initial movement direction and more frequently corrected their movements during task execution when compared to 9- and 11-year-old children who did not differ from each other. All age groups were similar in movement accuracy and precision. Movements toward contralateral targets were slower and more accurate than movements toward ipsilateral targets for all groups. These results show that performing aiming movements develop with the onset of middle childhood.

A blow-in type windowless gas target (BIGT) has been developed for nuclear experiments near stellar energy, especially for a 4 He+ 12 C→ 16 O+ γ experiment. The target has a multi-layer structure for differential pumping. Cooling of the target by liquid nitrogen was tried, and the target thickness was found to increase only 1.2 times under a constant gas flow rate. The present target thickness along a beam axis is 1.5 kPa×2.94 cm, which is about a half of our goal. A gas target having very thin windows was also developed using a 50 nm thick silicon nitride foil.

The incorporation of silicon into boron nitride thin films has been achieved by a negatively biased thin silicon rod being inserted into plasma during thin film growth in ultrahigh-vacuum sputtering. X-ray photoelectron spectroscopy and secondary ion mass spectroscopy indicated that the Si concentration and profile in the thickness direction were successfully controlled by changing the position of the rod during film growth. The deposition resulted in the formation of turbostratic boron nitride (tBN) when 4.4 at.% Si was incorporated before cBN nucleation. On the other hand, the cubic phase was formed when the same amount of Si was added after the nucleation. These results suggest that the amount of silicon impurities that suppresses cBN nucleation is less than that suppresses cBN growth.

The security of communication in everyday life becomes very important. On the other hand, all existing encryption protocols require from user additional knowledge end resources. In this paper we discuss the problem of public key distribution between interested parties. We propose to use a popular social media as a channel to publish public keys. This way of key distribution allows also easily connect owner of the key with real person institution (what is not always easy). Recognizing that the mobile devices become the main tool of communication, we present description of mobile application that uses proposed security methods.

Summary Objective Reversible lesion in the central area of the splenium of the corpus callosum (SCC) is a unique phenomenon occurring particularly in patients with encephalitis or encephalopathy and in patients receiving antiepileptic drugs (AED). We report MR imaging findings, clinical courses, and outcomes in eight patients with various diseases and conditions. Materials and methods Eight patients with a reversible SCC lesion with transiently restricted diffusion were reviewed retrospectively. Diseases and conditions that were associated with a reversible lesion included epilepsy receiving AED (n=1), seizure from eclampsia receiving AED (n=1), mild infectious encephalitis (n=2), hypernatremia resulting in osmotic myelinolysis (n = 1), and neoplasm (n=3) such as acute lymphocytic leukemia, spinal meningeal melanocytoma, and esophageal cancer. We evaluated MR imaging findings and clinical findings. Results Seven patients had isolated SCC lesions; one patient with osmotic myelinolysis showed additional parenchymal lesions. The reversible SCC lesion shape was oval (n=6) or extended (n=2). The mean apparent diffusion coefficient value of the splenial lesion was 0.40±0.16×10−3mm2/s, ranging from 0.22 to 0.64×10−3mm2/s. In a patient with osmotic myelinolysis, additional white matter lesions, shown as restricted diffusion, were revealed as not reversible on follow-up MR imaging. Neurological courses and outcomes were good in seven patients with isolated SCC lesions, but poor in one with osmotic myelinolysis. Conclusion Reversible SCC lesion with restricted diffusion is apparent in a wide spectrum of diseases and conditions. Neurological courses and outcomes are good, particularly in patients with isolated SCC lesions. Knowledge of MR imaging findings and the associated spectrum of diseases and conditions might prevent unnecessary invasive examinations and treatments.

Background: Patients with encephalopathy heralded by a prolonged seizure as the initial symptom often have abnormal subcortical white matter on diffusion-weighted MRI (DWI). Objective: To determine if these patients share other common features. Methods: Patients with encephalopathy heralded by a prolonged seizure and followed by the identification of abnormal subcortical white matter on MRI were collected retrospectively. Their clinical, laboratory, and radiologic data were reviewed. Results: Seventeen patients were identified, ages 10 months to 4 years. All had a prolonged febrile seizure (longer than 1 hour in 12 patients) as their initial symptom. Subsequent seizures, most often in clusters of complex partial seizures, were seen 4 to 6 days after the initial seizure in 16 patients. Outcome ranged from almost normal to severe mental retardation. MRI performed within 2 days of presentation showed no abnormality. Subcortical white matter lesions were observed on DWI between 3 and 9 days in all 17 patients. T2-weighted images showed linear high intensity of subcortical U fibers in 13 patients. The lesions were predominantly frontal or frontoparietal in location with sparing of the perirolandic region. The diffusion abnormality disappeared between days 9 and 25, and cerebral atrophy was detected later than 2 weeks. Three patients having only frontal lesions had relatively good clinical outcome. Conclusions: Although the pathophysiologic mechanism remains unknown, these patients seem to have a distinctive encephalopathy syndrome. MRI is helpful in establishing the diagnosis of this encephalopathy.

Two kinds of turbostratic boron nitride (tBN) thin films were deposited by sputtering with pure Ar or N2 plasma in an ultraclean vacuum chamber. Current–voltage (I–V) characteristics of Ti/tBN/Ti structures revealed that films deposited in Ar showed at least three-orders higher conductivity with strong temperature and electric field dependence compared with those deposited in pure N2. The origin of the higher conductivity was confirmed to be the nonstoichiometry and higher defect density of the tBN films. On the other hand, films deposited in pure N2 plasma showed the characteristics of intrinsic insulator even though the basal plane of tBN was oriented normal to the substrate, namely, parallel to the direction of electronic conduction.

A direct measurement of 4 He( 12 C, 16 O) γ reaction cross section is in progress at Kyushu University tandem laboratory (KUTL). A 12 C beam is incident on a windowless 4 He gas target. The 16 O recoils are separated from the beam by a recoil mass separator and are detected by a Si-detector. In order to increase beam intensity, target thickness and detection efficiency, original instruments and methods have been newly developed. To reduce background (BG), a beam from the tandem accelerator was pulsed. Recently a long-time chopper was developed to further separate the reaction recoils and BG, and a test measurement of 4 He( 12 C, 16 O) γ reaction cross section at E cm = 2.4 MeV was made.

Direct measurement of the 4 He( 12 C, 16 O) γ reaction cross section by detecting 16 O recoils is in progress at Kyushu University tandem laboratory (KUTL). A long-time chopper (LTC) has been developed to reject backgrounds from 16 O recoils which have time (energy) spread. In the measurement of 4 He( 12 C, 16 O) γ cross section at E cm = 2.4 MeV, LTC was found to reduce the backgrounds by about three orders of magnitude.

The spin alignment and cross section have been measured in the 12 C+ 16 O inelastic scattering for the 12 C(g.s.)+ 16 O(3 − 1 , 6.13 MeV) and 12 C(2 + 1 , 4.44 MeV)+ 16 O(g.s.) channels at E c.m. =17–23 MeV. In both channels, three weakly excited resonant structures are newly observed. Our result of spin alignment in the former channel well reproduces that of the previous study [Phys. Lett. B 120 (1983) 314]. In the latter channel the spin alignment is more or less enhanced at all intermediate structures. The spin alignment data integrated from forward to backward angles in this channel may indicate the presence of gross structure resonances.

A recoil mass separator designed to achieve a highest possible capability of the background rejection in the condition of inverse kinematics has been developed at Kyushu University tandem accelerator laboratory. Developments at accelerator have also been carried out to obtain a pulsed beam of high current and good emittance. With the mass separator and the pulsed heavy-ion beam, we are about to start the investigation of the 4 He( 12 C, 16 O)γ reaction of astrophysical interest.

BACKGROUND AND PURPOSE: Hemimegalencephaly is a rare but well-known congenital malformation with ipsilateral enlargement of the hemicerebrum. However, very little is known about changes in structures outside the involved hemisphere in patients with this condition. We investigated morphologic abnormalities occurring outside the affected hemisphere by MR imaging in a large series of patients with hemimegalencephaly. MATERIALS AND METHODS: MR imaging findings for 30 patients with hemimegalencephaly were retrospectively reviewed and evaluated for structures outside the involved hemisphere on routine MR images, such as cranial nerves (I, II, V), brain vessels, subdural and subarachnoid spaces, brain stem, and cerebellum, on both the ipsilateral and contralateral sides. RESULTS: The ipsilateral olfactory and optic nerves were enlarged in 8 (26.7%) and 1 (3.3%) of the 30 patients, respectively, without enlargement on the contralateral side. No asymmetry was noted in the trigeminal nerves. Asymmetric vascular dilations in the ipsilateral cerebral hemisphere were observed in 12 of the 30 patients (40%), in deep cerebral vessels in 11 patients (36.7%), and in superficial cerebral vessels in 8 patients (26.7%). Ipsilateral brain stem and hemicerebellar asymmetric enlargement was detected in 2 patients (6.7%) and 14 patients (46.7%), respectively. Abnormal cerebellar folia were observed on the ipsilateral side in 6 patients (20%) and on the contralateral side in 3 patients (10%). CONCLUSION: Ipsilateral olfactory nerve enlargement, cerebral vascular dilations, cerebellar enlargement, and bilateral or ipsilateral abnormal architecture of the cerebellar folia are often associated with hemimegalencephaly.

Preparation for direct measurement of 12C+4He→16O+γ reaction at stellar energy has been made in Kyushu University tandem laboratory (KUTL) since 1914. We plan to measure the reaction at Ecm = 2.4–0.7 MeV where the cross section is estimated to be 60 nbarn–1pbarn. Many instrumental developments have been made for a 12C beam, a windowless helium gas target, 16O detection, background reduction. We started the measurement in 2006.

Objective: To clarify whether patients with clinical diagnoses of encephalitis/encephalopathy with a reversible lesion in the splenium of the corpus callosum (SCC) share common clinical features. Methods: Possible encephalitis/encephalopathy patients with a reversible isolated SCC lesion on MRI were collected retrospectively. Their clinical, laboratory, and radiologic data were reviewed. Results: Fifteen encephalitis/encephalopathy patients with a reversible isolated SCC lesion were identified among 22 patients referred for this study. All 15 patients had relatively mild clinical courses. Twelve of the 15 patients had disorders of consciousness. Eight patients had seizures, and three of them received antiepileptic drugs. All 15 patients clinically recovered completely within 1 month (8 patients within a week) after the onset of neurologic symptoms. The SCC lesion was ovoid in six patients; it extended irregularly from the center to the lateral portion of SCC in the other eight patients. Homogeneously reduced diffusion was seen in all seven patients who underwent diffusion-weighted imaging. There was no enhancement in the five patients so examined. The SCC lesion had completely disappeared in all patients at follow-up MRI exams between 3 days and 2 months after the initial MRI (within 1 week in eight patients). Conclusion: The clinical features among the affected patients were nearly identical, consisting of relatively mild CNS manifestations and complete recovery within 1 month.

To examine whether the pituitary gland enlarges in patients with spontaneous intracranial hypotension (SIH).All six patients were women ranging in age from 17 to 51 years. They developed severe headache that was completely relieved by lying flat, and MR imaging showed diffuse enhancement of the pachymeninx. They were clinically diagnosed with SIH. The height of the pituitary gland was measured on midsagittal MR image.Pituitary heights ranged from 8 to 11 mm. The measurements were greater than the size of the normal pituitary gland in women described age-matched in the previous report. In one case, follow-up MR images showed that the size of the pituitary gland was decreased from 11 to 5 mm in height.The pituitary gland was enlarged in all six patients with SIH on MR images. SIH may cause enlarged pituitary gland.

To define the frequency of decreased signal intensity (DSI) in cerebral cortex on T2-weighted images relative to aging and to the incidence of identifying white matter pathology, T2-weighted MR brain images of 906 patients consecutively examined between July 1989 and June 1991 were reviewed. MR images of cerebral cortex were divided into five areas: frontal lobe (F), pre- and postcentral gyri (C), parietal lobe (P), occipital lobe (O) and temporal lobe (T). Each area was separately and independently evaluated for the presence or absence of DSI. The frequency of DSI in each area was plotted against patients' ages. The severity of leukoaraiosis was evaluated in relation with DSI in each cortical area. Patients with DSI in area F numbered 61 (5.7%), in area C 236 (26.0%), in area P 174 (15.9%), in area O 428 (47.2%), and in area T 10 (1.1%). The number of patients with DSI in each area increased with age. The greater the severity of leukoaraiosis, the greater the chance of finding DSI of the cerebral cortex. The incidence of DSI in the cerebral cortex increased with the patient's age as well as with the severity of co-existent white matter pathology.

Thallium-201 (201Tl) SPECT was performed 48 times in 26 patients to clarify its usefulness in the evaluation of malignancy and viability of brain tumors. The early counts ratio (ER) and delayed counts ratio (DR) of a lesion compared with normal brain were obtained 10-15 minutes and 3 hours, respectively, after intravenous administration of 185 MBq of 201Tl chloride. Untreated high grade malignant tumors and recurrent tumors did not always show high ER and DR, and they were widely distributed. High grade malignant tumors that showed low ER and DR were not well enhanced on CT or MRI. In low grade malignant tumors, such as pituitary adenoma which was well enhanced on CT, ER and DR were as high as in high grade malignant tumor. Whether a tumor recurred within three months after radiotherapy or not was retrospectively predicted at accuracy rates of 93.8% and 87.5% with cut-off points of 4.0 for ER and 3.5 for DR. Cerebral radiation necrosis showed ring-like increased uptake of 201Tl in proportion to the progress of necrosis and intensity of enhancement on MRI. In conclusion 201Tl SPECT is considered to be less useful for lesions that are well enhanced on CT, because they show high uptake of 201Tl regardless of their malignancy and viability. On the other hand, in tumors that are not well enhanced on CT. 201Tl shows good accumulation in viable and high grade malignant lesions. 201Tl SPECT should be performed in such cases.

Invasive pulmonary aspergillosis generally occurs in immunocompromised hosts such as patients with leukemia, and other malignancies, who are receiving anti-cancer chemotherapy. In this report, two non-immunocompromised patients who developed invasive pulmonary aspergillosis are presented. Case 1: A 63-year-old man complained of productive cough and fever. He received antibiotic therapy from his personal physician. This symptoms did not respond, however, and dyspnea developed. He was then transferred to our hospital, about one month after the onset. The chest X-ray showed a meniscus shadow suggesting an aspergilloma in the right upper lung field and an infiltrative shadow in the remaining right lung field. Case 2: A 78-year-old man was admitted because of dyspnea, productive cough and appetite loss over the previous three months. The chest X-ray showed a meniscus shadow in the left upper field, an infiltrative shadow in the left lower field and a right pleural effusion sign was also observed. Both cases were diagnosed as having aspergillosis, early in their illness, by the detection of aspergillus antigen in their sera and histopathological and cultural studies of specimens obtained by TBLB. Both improved with intravenous amphotericin B (30 mg/day) and intravenous ulinastatin (200000 IU/day) administration. On the examinations conducted during hospitalization, there was no evidence of any immunosuppressive diseases or immunoincompetent conditions such as leukemia, and other malignancies human immunodeficiency virus infection, diabetes or alcoholism.

Intracavitary irradiation using a high-dose-rate Ir-192 remote after-loading system was applied to 14 advanced or inoperable patients with esophageal carcinoma as a boost therapy. The total dose of external irradiation was 45-70 Gy/15-35 fractions and that of intracavitary irradiation was 11.6-34.0 Gy/2-4 fractions at a point 5 mm deep from the inner surface of the esophageal mucosa. The time-dose-fractionation factor (TDF) of the whole treatment was 116-186 (mean, 146). Six patients (43%) had complete response (CR), three (21%) had partial response and five (36%) had no response. Esophageal carcinoma that showed exophytic growth, was less than 5 cm ling, and showed favorable response to external irradiation was likely to be a good candidate for intracavitary radiation boost therapy. Fistula formation was produced in five patients (36%), four of whom were irradiated at more than 140 TDF. All six CR patients were free from esophageal tumors, but severe esophageal stenosis due to radiation injury developed in five (83%) of them. They were irradiated at more than 135 TDF. One- and two-year survival rates were 28.6% and 14.3%, respectively. The poor prognosis was ascribed to the frequent occurrence of fatal radiation stenosis and fistula formation. An appropriate therapeutic dose for esophageal carcinoma that does not cause severe radiation stenosis was estimated to be under 120 TDF.

Magnetic resonance imaging (MR imaging) provides a sensitive method for mapping the normal and pathological distribution of iron in the brain. High field strength MR imaging (1.5 T) was used to evaluate eight patients with amyotrophic lateral sclerosis (ALS) and 49 neurological normal control patients. All eight ALS patients showed decreased signal intensity in the motor cortex on T2-weighted images, while only one of the normal control patients showed this finding. The results suggested that the decreased signal intensity in the motor cortex in ALS was caused by the deposition of iron in this area.

The pathophysiologic significance of iodoamphetamine (IMP) redistribution was analyzed using a double radionuclide autoradiography technique in experimental brain ischemia in the rat. Within 4 hr after unilateral arterial occlusion, IMP almost completely redistributed at 150 min postinjection in the affected areas. At 2 min postinjection, both a remarkable decrease of IMP accumulation and histopathologic change of diminished staining were observed in these areas. The redistribution amplitude was higher in the affected hemisphere, especially in the regions surrounding the ischemic core than in the unaffected hemisphere. These findings were consistent with computer simulation studies of the time course of brain activity based on the standard diffusible tracer model. The results suggest that IMP redistribution in the ischemic area is due to differences of the temporal changes of the brain activity between the unaffected and affected areas and that it is a "physical" phenomenon (only flow related) rather than a "biologic" one.

A newly developed instrument based on dual energy X-ray absorptiometry (DEXA), Hologic QDR-1000, was evaluated fundamentally and clinically. Image quality was quite satisfactory though radiation exposure was minimal, 780.2 nC/kg (3.024 mR) for lumbar measurement. Reproducibility of the repeated measurement of a phantom was fairly good; 0.343 CV% in a same day and 0.520 CV% in a long period. Accuracy determined by measurement of potassium phosphate solution was also satisfactory. Bone mineral densities measured by this instrument were fairly correlated with those measured by single energy quantitative CT; coefficient was 0.740 for 17 patients. Mix-DP plates of more than 10 cm thick overestimated the bone mineral densities of a phantom. Bone mineral densities of Japanese normal volunteers were in the normal range (mean +/- 2SD) of the Americans though mostly lower than the mean. In patients with spondylosis deformans or prominent aortic calcification, bone mineral densities might be overestimated. Lateral view was obtainable though its reproducibility was not good. Positioning especially for measuring femoral neck was quite critical for reproducible measurement. In conclusion, this new instrument is quite accurate and satisfactory for clinical application to measuring bone mineral densities.

The authors demonstrate that the electric conductivities of cubic and hexagonal boron nitride (c-BN and h-BN) thin films increased markedly by the in situ doping of zinc. The doped films were electrically semiconducting, and conductivities at room temperature increased from 10−8to10−2Ω−1cm−1 with increasing zinc concentration from 400to20000ppm. Activation energies for electric conduction (Ec) of c-BN decreased from 0.3to0.1eV with increasing zinc concentration, suggesting feasible shallow-level doping. On the other hand, h-BN thin films showed approximately 0.1eV higher Ec than those of c-BN’s, due to the formation of defective B–B bonds.

Three cases with cerebral ischemic symptoms and an intracranial aneurysm are presented. Using [99mTc]hexamethyl-propyleneamine oxime (HM-PAO) single photon emission computed tomography imaging before and during the Matas test, a quantitative measurement method was developed for evaluating brain collateral circulation. The evaluation correlated well with findings of contrast carotid angiography. This noninvasive method seems to be useful for selection of patients for appropriate surgical treatment.

Organic dyes, which are utilized for optical recording medium, have some excellent characteristics such as anti-oxidizing, non-toxic, high resolution, and so on. And some kind of dyes show such a high reflectivity like metals near the wavelength region corresponding to the absorption.

The applicability of a lipid microsphere drug delivery system to ophthalmic preparations was examined using a lipid microsphere containing hydrocortisone 17-butyrate 21-propionate (HBP). 3H-labelled HBP ophthalmic suspension and 3H-labelled HBP lipid microsphere were applied to rabbit eyes, and the eyes were enucleated after 1 and 3 hours to determine 3H-labelled HBP levels in the ocular tissues. The lipid microsphere proved to deliver the drug to the anterior ocular tissues more significantly than the ophthalmic suspension. It is suggested that the lipid microsphere ophthalmic preparation of various lipophilic drugs including steroids may be useful as one of the drug delivery systems for ophthalmic therapy.

The use of a nomogram is described as a new noninvasive quantitative assessment of cerebral blood flow using N-isopropyl-(123I)p-iodoamphetamine (IMP) and single-photon emission computed tomography. The nomogram was constructed from a computer analysis of the flow value relative to varying washout rate of brain activities between early and late tomographic images, and partition coefficient between brain tissue and blood. The validity of this method was evaluated in normal volunteers and in patients with cerebrovascular disorders by comparing the cortical flow values (Y) estimated from the IMP-nomogram with initial slope indices (X) by the 133Xe inhalation method. A significant correlation (N = 42, r = 0.88, P less than .001) was demonstrated between them, and the regression line was Y = 1.6X-7. A development and confirmation of this method made it possible to measure flow values noninvasively with the use of IMP.

A new double tracer autoradiographic method for the sequential evaluation of altered regional cerebral perfusion in the same animal is presented. This method is based on the sequential injection of two tracers, 99mTc-hexamethylpropyleneamine oxime and N-isopropyl-(125I)p-iodoamphetamine. This method is validated in the assessment of brovincamine effects on regional cerebral perfusion in an experimental model of chronic brain ischemia in the rat. The drug enhanced perfusion recovery in low-flow areas, selectively in surrounding areas of infarction. The results suggest that this technique is of potential use in the study of neuropharmacological effects applied during the experiment.