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The complete automation of materials manufacturing with high productivity is a key problem in some materials processing. In floating zone (FZ) crystal growth, which is a manufacturing process for semiconductor wafers such as silicon, an operator adaptively controls the input parameters in accordance with the state of the crystal growth process. Since the operation dynamics of FZ crystal growth are complicated, automation is often difficult, and usually the process is manually controlled. Here we demonstrate automated control of FZ crystal growth by reinforcement learning using the dynamics predicted by Gaussian mixture modeling (GMM) from small numbers of trajectories. Our proposed method of constructing the control model is completely data-driven. Using an emulator program for FZ crystal growth, we show that the control model constructed by our proposed model can more accurately follow the ideal growth trajectory than demonstration trajectories created by human operation. Furthermore, we reveal that policy optimization near the demonstration trajectories realizes accurate control following the ideal trajectory.

Genus Dendrobium (Orchidaceae) contains numerous species. Phylogenetic analyses based on morphological characteristics and DNA sequences indicated that this genus is divided into two major groups: Asian and Australasian clades. On the other hand, little is known about the phytochemical differences and similarities among the species in each clade. In this study, we selected 18 Dendrobium species (11 from the Asian clade and 7 from the Australasian clade) and constructed HPLC profiles, arrays composed of relative intensity of the chromatographic peaks. Next, orthogonal partial least square discriminant analysis (OPLS-DA) was applied to the profile matrix to classify Dendrobium species into the Asian and Australasian clades in order to identify the peaks that significantly contribute to the class separation. In the end, two phenanthrenes, 4,9-dimethoxyphenanthrene-2,5-diol 1 and 1,5-dimethoxyphenanthrene-2,7-diol 2, which contributed to the class separation, were isolated from the HPLC peaks. The existence of 2 was limited to the genetically related Australasian species.

Kenji Nakamura, Yuta Yamada, Takashi Ohinata*, Kenji Arimatsu*, Takehiko Kojima**, Makoto Yamada**, Ryohei Matsumoto**, Masaya Takiguchi**, and Osamu Ichinokura Graduate School of Engineering, Tohoku University, 6-6-05 Aoba Aramaki Aoba-ku, Sendai 980-8579, Japan *Tohoku Electric Power Co., Inc., 1-7-1 Honcho Aoba-ku, Sendai 980-8550, Japan **Fuji Electric Co., Inc., 1-11-2 Osaki Shinagawa-ku, Tokyo 141-0032, Japan

Genus Dendrobium (Orchidaceae) contains numerous species. Phylogenetic analyses based on morphological characteristics and DNA sequences indicated that this genus is divided into two major groups: Asian and Australasian clades. On the other hand, little is known about the phytochemical differences and similarities among the species in each clade. In this study, we selected 18 Dendrobium species (11 from the Asian clade and 7 from the Australasian clade) and constructed HPLC profiles, arrays composed of relative intensity of the chromatographic peaks. Next, orthogonal partial least square discriminant analysis (OPLS-DA) was applied to the profile matrix to classify Dendrobium species into the Asian and Australasian clades in order to identify the peaks that significantly contribute to the class separation. In the end, two phenanthrenes, 4,9-dimethoxyphenanthrene-2,5-diol 1 and 1,5-dimethoxyphenanthrene-2,7-diol 2, which contributed to the class separation, were isolated from the HPLC peaks. The existence of 2 was limited to the genetically related Australasian species.

This study experimentally investigated the atomic structure of a single-crystalline Mn-doped BiFeO3 (BFO) thin film using X-ray fluorescence holography with synchrotron radiation. Bi atoms can be reconstructed from both Fe Kβ and Mn Kα fluorescence X-ray holograms, indicating Mn doping at B sites in ABO3-type perovskite structure. The fluorescence intensity of the 1st to 4th nearest Bi atoms around target Fe atoms was lower than those around Mn atoms, confirming the selective formation of Bi vacancies around Fe atoms. In contrast, the 5th to 8th nearest Bi atoms around Fe atoms showed higher intensities than those around Mn atoms, indicating that the Mn-doped BFO thin film had a double-perovskite-like structure. These results provide important information that helps elucidate the mechanism by which Mn doping modifies the conductivity of BFO.

To explore whether the 'hikikomori' syndrome (social withdrawal) described in Japan exists in other countries, and if so, how patients with the syndrome are diagnosed and treated.Two hikikomori case vignettes were sent to psychiatrists in Australia, Bangladesh, India, Iran, Japan, Korea, Taiwan, Thailand and the USA. Participants rated the syndrome's prevalence in their country, etiology, diagnosis, suicide risk, and treatment.Out of 247 responses to the questionnaire (123 from Japan and 124 from other countries), 239 were enrolled in the analysis. Respondents' felt the hikikomori syndrome is seen in all countries examined and especially in urban areas. Biopsychosocial, cultural, and environmental factors were all listed as probable causes of hikikomori, and differences among countries were not significant. Japanese psychiatrists suggested treatment in outpatient wards and some did not think that psychiatric treatment is necessary. Psychiatrists in other countries opted for more active treatment such as hospitalization.Patients with the hikikomori syndrome are perceived as occurring across a variety of cultures by psychiatrists in multiple countries. Our results provide a rational basis for study of the existence and epidemiology of hikikomori in clinical or community populations in international settings.

Aims: Previous morphometric studies using magnetic resonance imaging (MRI) have revealed structural brain abnormalities in obsessive–compulsive disorder (OCD). The aim of the present study was to investigate the alterations in brain structure of patients with OCD using a voxel-based morphometry (VBM) method. Methods: Sixteen patients with OCD free of comorbid major depression, and 32 sex- and age-matched healthy subjects underwent MRI using a 1.5-T MR scanner. OCD severity was assessed with the Yale–Brown Obsessive–Compulsive Scale (mean ± SD: 22 ± 7.6; range: 7–32). MR images were spatially normalized and segmented using the VBM5 package (http://dbm.neuro.uni-jena.de/vbm/). Statistical analysis was performed using statistical parametric mapping software. Results: Significant reductions in regional gray matter volume were detected in the left caudal anterior cingulate cortex and right dorsal posterior cingulate cortex in the patients with OCD as compared to healthy controls (uncorrected, P

Inflammatory/immunological process and glial contribution are suggested in the pathophysiology of schizophrenia. We investigated peripheral benzodiazepine receptors in brains of patients with chronic schizophrenia, which were reported to be located on mitochondria of glial cells, using [11C]DAA1106 with positron emission tomography. Fourteen patients and 14 age- and sex-matched normal controls participated in this study. PET data were analysed by two-tissue compartment model with metabolite-corrected plasma input. Clinical symptoms were assessed using the Positive and Negative Syndrome Scale. There was no significant difference between [11C]DAA1106 binding of the cortical regions of normal controls and patients with schizophrenia, whereas the patients showed a positive correlation between cortical [11C]DAA1106 binding and positive symptom scores. There was also a positive correlation between [11C]DAA1106 binding and duration of illness. Although the correlations need to be interpreted very cautiously, involvement of glial reaction process in the pathophysiology of positive symptoms or progressive change of schizophrenia might be suggested.

Aims Abnormality of cognitive function in schizophrenia has been suggested to be related to dopamine D1 receptor. However, the results of previous positron emission tomography (PET) studies of dopamine D1 receptor in schizophrenia were not consistent. Main methods In this study, six patients with schizophrenia in severe residual phase with chronic antipsychotic treatment and twelve healthy age-matched controls participated. Two different radioligands, [11C]NNC112 and [11C]SCH23390, for dopamine D1 receptor were used on the same subjects. Binding of the ligands was measured by PET, and statistical analysis was performed using one-way analysis of covariate (ANCOVA) with age as covariate. Key findings Good correlations between binding potential values (BPND) and age were observed in all regions of interest (ROIs) with both ligands. ANCOVA with age as covariate of BPND values of all ROIs revealed that the patient group showed significantly lower BPND value compared with the control group in both ligands. Significance In patients with chronic schizophrenia in severe residual phase with chronic antipsychotic treatment, the binding potential values of both ligands were significantly lower in the striatum and cortical regions than those of healthy controls.

The serotonin transporter (5-HTT) and other markers of the serotonergic system have been of interest in the pathophysiology of obsessive-compulsive disorder (OCD). Previous studies using single photon emission computed tomography (SPECT) with [(123)I]beta-CIT or positron emission tomography (PET) with [(11)C]McN5652 have not shown consistent findings about 5-HTT in OCD patients. The aim of the present study was to investigate 5-HTT binding using [(11)C]DASB, which has higher selectivity or specific binding-to-nonspecific binding ratios for 5-HTT compared to the aforementioned radioligands. Four drug-naive and 6 drug-free patients with OCD who were free of comorbid depression and 18 gender and age-matched healthy subjects underwent PET scans with [(11)C]DASB. The severity of OCD was assessed by Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) (mean+/-SD: 22+/-7.6, range: 7-32). The binding potential (BP(ND)) of [(11)C]DASB was calculated using a two-parameter multilinear reference tissue model (MRTM2). The parametric images of BP(ND) were analyzed using a statistical parametric mapping system. Significant reductions of BP(ND) were observed in the right posterior and left anterior insular cortices in patients with OCD compared to controls. Region-of-interest analysis has also confirmed significant reduction of BP(ND) in the insular cortex. Although significantly reduced BP(ND) in the orbitofrontal cortex was also observed in patients with OCD compared to controls, this finding should be considered with caution because of the very low 5-HTT binding in the region. On the other hand, no significant correlation was observed between the Y-BOCS score and BP(ND). The change in [(11)C]DASB binding in the insular cortex suggests that dysfunction of the serotonergic system in the limbic area might be involved in the pathophysiology of OCD.

To evaluate the cytotoxicity and the tribological properties for diamond-like carbon films (DLC), DLC films were deposited on high-polymer materials such as polymethylmethacrylate, polycarbonate, polyurethane and polytetrafluoroethylene using a radio-frequency chemical vapor deposition (CVD) system. Adhesion strength between these materials and DLC films is generically poor. To improve adhesion strength of DLC films and high-polymer materials, oxygen plasma pretreatment was performed before DLC films deposited. Evaluation of the tribological properties was performed using ball-on disc system. Especially, in the DLC films deposited on PMMA with oxygen plasma pretreatment, the friction coefficient was significantly reduced from 0.456 to 0.310. Influence of DLC films on cytotoxicity were studied in vitro cell culture by counting cells. Mouse fibroblasts (NIH-3T3) were seeded in 24 well culture plates, and four kinds of high-polymer PMMA, PC, PU and PTFE substrates, DLC-deposited and non-deposited high-polymer substrates, were immersed in each well directly for 24, 48, 72, and 96 h. Multiplication of cell number with DLC-deposited substrates is similar in that with non-deposited substrates. Consequently, these studies reveal that the DLC films have excellent tribological properties and cytocompatibility.

Thalamic nuclei respectively comprise fibers connecting associated cortical regions, and abnormalities of the thalamus are correlated with abnormalities in cognition and behavior. Some previous studies showed the laterality of the whole thalamus and the regional differences among thalamic nuclei. This led us to assess regional characteristics in five major subregions of both sides of the thalamus using diffusion-tensor imaging. There were statistically significant lateralities and regional differences among the thalamic subregions. Age has significant correlation with diffusion-tensor imaging metrics where their projection areas are thought to be vulnerable to normal aging. Our results confirmed that the thalamic subregions behave independently, and their respective microstructures warrant further investigations.

セロトニントランスポーターは多くの抗うつ薬の主要な結合部位のひとつであり，うつ病の発現に重要な役割を果たしていることが想定されている．PET（positron emission tomography）では，セロトニントランスポーターに特異結合する放射性リガンドを用いて，ヒト脳内のセロトニントランスポーターをin vivoで定量することが可能である．実際に，PET研究で，視床のセロトニントランスポーターがうつ病患者群において，増加していることが報告されており，セロトニントランスポーターがうつ病の病態に大きな役割を果たしていると推察できる．また，健常者において，うつ病の発症脆弱性が，視床におけるセロトニントランスポーターの発現と関連している可能性もPET研究から示唆されている．一方，セロトニン神経系の起始核がある中脳での有意な変化は，PET研究では報告されておらず，今後の知見の集積がまたれる．抗うつ薬のPETによる評価としては，セロトニントランスポーターに対して特異的に結合する放射性リガンドと抗うつ薬が競合阻害することから，占有率を算出して評価する方法が一般的である．PETを用いて，抗うつ薬による脳内セロトニントランスポーターの占有率およびその経時変化を測定することで，血中の薬剤濃度や半減期に比して，より適切な臨床用量や投与方法が設定可能である．実際に，既存の薬剤の再評価に加え，日本国内でも，新規抗うつ薬の治験にPETが使用されている．今後，新規の抗うつ薬の開発にPETが重要な役割を果たすことが，期待されている．

A variable inductor, which consists of only magnetic core and primary dc and secondary ac windings, can control effective inductance of the secondary ac winding by the primary dc current due to the magnetic saturation effect. Hence, the variable inductor can be applied as a VAR compensator for voltage regulation in electric power systems. In a previous paper, a novel concentric-winding type three-phase variable inductor was proposed, in which the primary dc and secondary ac windings are concentrically wound on the same leg. It was indicated by a numerical analysis that the proposed variable inductor has good controllability and low distortion current. This paper presents the experimental results of a 4 kVA concentric-winding type threephase variable inductor. Furthermore, to prove the advantage of the proposed variable inductor, copper and iron losses, leakage flux, and reactive power per weight are compared with those of the previous variable inductor. It is demonstrated that the copper loss of the proposed variable inductor is improved by 40%, the leakage flux is reduced by half, and the weight can be reduced by 40% in comparison with the previous variable inductor.

Background An abnormality in regional cerebral blood flow (rCBF) in anorexia nervosa (AN) patients has been reported. There are very few studies that have investigated the rCBF changes in the recovery process of AN. Methods For eight female AN patients, we performed 123 I-IMP single photon emission computed tomography (SPECT) and four psychological assessments (Eating Disorder Inventory (EDI), Eating Attitude Test (EAT), Self-Rating Depression Scale (SDS) and State-Trait Anxiety Inventory (STAI)) both before and after inpatient-behavioral therapy. SPECT images were analyzed using statistical parametric mapping software. We also performed correlational analysis between rCBF and clinical variables. Results Following treatment, the patients showed significant body weight recovery. They showed significant improvement in EAT, SDS, STAI and a subscale of EDI – interoceptive awareness (IA) – but not in total EDI or other EDI subscales. Significant rCBF increases were observed in the precuneus, posterior cingulate cortex (PCC), right dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex (ACC) and medial prefrontal cortex (MPFC) by the treatment. Significant correlation was observed between rCBF of right DLPFC and IA score before treatment. Conclusions Changes of rCBF in right DLPFC, ACC, MPFC, PCC and precuneus were related to the AN recovery process and might be associated with improvement of IA following treatment.

The psychiatric specialist certification system of the Japanese Society of Psychiatry and Neurology was established in 2005, with a transitional period that ran until 2008. A three-year postgraduate training scheme was started in connection with the new psychiatric specialist certification system, and the first formal examination under the new system was held in 2010. A resident desiring certification as a psychiatric specialist must purchase a psychiatric specialist certification handbook and present it when taking the examination. There are many differences between the new examination and the transitional period examination, in terms of both the handbook and the number of case reports to be submitted. Results of a survey conducted on 360 psychiatrists belonging to either university or national hospitals, all of whom had undergone psychiatric training within the past eight years, revealed that there was currently a lack of knowledge, and low rate of utilization, of the handbook. The primary author was in the first cohort of those who began postgraduate psychiatric training in a university hospital and subsequently took the first examination administered after the transition period. The author has maintained that, based on personal experience, a number of issues need improvement, such as the large number of grading items to be signed off on by supervising psychiatrists, and complications involving the outline of cases to be experienced. Additionally, it was thought to be difficult for supervisors who had obtained their specialist certification via the transitional period examination to have an adequate understanding of the outline of the new examination. Therefore, it is important that residents themselves take a more assertive attitude to becoming specialists. In the future, in order to establish a sound specialist certification system, the results of this survey of physicians who took the new examination should be taken into account.

Aim Japanese psychiatrists have increasingly reported patients with depression that does not seem to fit the criteria of the ICD-10 and the DSM-IV, and which has recently been called modern type depression (MTD). We explored whether MTD is frequently seen in Japan and also in other countries, and if so, how patients with MTD are diagnosed and treated. Methods The questionnaires, with two case vignettes (traditional type depression (TTD) and MTD), were sent to psychiatrists in Australia, Bangladesh, India, Iran, Japan, Korea, Taiwan, Thailand and the USA. Participants rated their opinions about each case's prevalence in their country, etiology, diagnosis, suicide risk, and treatment using Likert scales. Results Out of 247 responses (123 from Japan and 124 from other countries), two hundred thirty-nine valid responses were received. MTD was recognized in all participating countries, and especially in urban areas. Generally, the factor of personality was regarded as the most probable cause of MTD. Whereas about 90% of Japanese psychiatrists applied the ICD/DSM criteria to TTD, only about 60% applied the criteria to MTD. Conclusion Our results indicate that Japan's MTD seems to be occurring in many other countries, and that the present ICD/DSM criteria may not be sufficient to diagnose MTD. Therefore, it could be an important candidate for a new international diagnostic criterion as a subtype of depression. A clear diagnostic framework and consensus on the interventions to treat MTD would be valuable. Further clinical, psychopathological and international epidemiological studies are needed to confirm our preliminary findings of MTD.

Previous morphometric studies using magnetic resonance imaging (MRI) have revealed structural brain abnormalities in obsessive-compulsive disorder (OCD). The aim of the present study was to investigate the alterations in brain structure of patients with OCD using a voxel-based morphometry (VBM) method.Sixteen patients with OCD free of comorbid major depression, and 32 sex- and age-matched healthy subjects underwent MRI using a 1.5-T MR scanner. OCD severity was assessed with the Yale-Brown Obsessive-Compulsive Scale (mean ± SD: 22 ± 7.6; range: 7-32). MR images were spatially normalized and segmented using the VBM5 package (http://dbm.neuro.uni-jena.de/vbm/). Statistical analysis was performed using statistical parametric mapping software.Significant reductions in regional gray matter volume were detected in the left caudal anterior cingulate cortex and right dorsal posterior cingulate cortex in the patients with OCD as compared to healthy controls (uncorrected, P0.001). No significant differences in white matter volumes were observed in any brain regions of the patients. No significant correlation between Yale-Brown Obsessive-Compulsive Scale score and regional gray matter or white matter volume was observed.Regional gray matter alteration in the dorsal cingulate cortex, which is suggested to play a role in non-emotional cognitive processes, may be related to the pathophysiology in OCD.

The dopamine hypothesis has been the most widely known theory concerning schizophrenia. However, the exact mechanism including presynaptic dopaminergic activity and its relationship with symptom severity still remains to be revealed. We measured presynaptic dopamine synthesis using positron emission tomography (PET) with L-[β- 11 C]DOPA in 18 patients with schizophrenia (14 drug-naive and 4 drug-free patients) and 20 control participants. Dopamine synthesis rates, expressed as k i values, were obtained using a graphical method, and the occipital cortex was used as reference region. Regions of interest were placed on the prefrontal cortex, temporal cortex, anterior cingulate, parahippocampus, thalamus, caudate nucleus, and putamen. Psychopathology was assessed with the Positive and Negative Symptom Scale (PANSS). We found significantly higher k i values in patients than in controls in the left caudate nucleus, but not in the other regions. The k i values in the thalamus exhibited a significant positive correlation with the PANSS total scores. Furthermore, a significant positive correlation was observed between the PANSS positive subscale scores and k i values in the right temporal cortex. Patients with schizophrenia showed higher dopamine synthesis in the left caudate nucleus, and dopaminergic transmission in the thalamus and right temporal cortex might be implicated in the expression of symptoms in schizophrenia.

Background Abnormalities of fractional anisotropy (FA) have been reported in previous diffusion tensor imaging (DTI) studies in patients with obsessive–compulsive disorder (OCD). However, there are some inconsistencies in the results and the apparent diffusion coefficient (ADC) has not been investigated. The goal of this study was to investigate white matter abnormalities and water diffusivity, as reflected by FA and ADC, using DTI in patients with OCD. Methods Fifteen patients with OCD and 15 healthy volunteers underwent DTI. Voxelwise analysis was used to compare FA in white matter and ADC in gray matter/white matter of the two groups. Results Compared with healthy volunteers, the patients had higher FA in the bilateral semioval center extending to the subinsular white matter; and a higher ADC in the left medial frontal cortex. There were no areas with a significantly lower FA or ADC in patients compared with healthy volunteers. Conclusions A significantly higher FA was found in regions associated with the emotion of disgust and a trend for a higher ADC was found in a region associated with the regulation of emotions. These findings suggest that neurocircuits involved in disgust processing may play an important role in the pathophysiology of OCD.

N-methyl-D-aspartate (NMDA) receptors are of major interest in brain functions and neuropsychiatric disorders. However, at present there are few suitable radioligands for in vivo imaging of NMDA receptors. 7-choloro-4-hydroxy-3-[3-(4-methoxybenzyl) phenyl]-2(1H)-quinolone (L-703,717) is one of the potent ligands for the glycine-binding site of NMDA receptors. 4-Acetoxy derivative of L-703,717 (AcL703) is a candidate, as a positron emission tomography (PET) ligand for NMDA receptors, because of its better permeability at the blood-brain barrier compared with L-703,717. After intravenous injection of 624-851 MBq of [11C]AcL703, dynamic PET scan was performed on six healthy males for 90 min. Regions-of-interest were located on the cerebral cortices, cerebellar cortex, and cerebral white matter. The binding potential (BP) was calculated from the ratio of the area under the curve (AUC) of radioactivities from 40 to 90 min in the target region to that in white matter. Regional radioactivities reached close to equilibrium in all regions after about 40 min postinjection. Regional brain uptake of [11C]AcL703 at 40 min after injection was 0.00028-0.00065% of the injected dose/milliliter. Radioactivity concentration of [11C]AcL703 was highest in the cerebellar cortex and lowest in white matter. AUC in the cerebellar cortex was higher than those of cerebral cortices, thalamus, striatum, and white matter. BP in the cerebellar cortex was twofold higher than in the cerebral cortices (cerebellar cortex: BP=2.20+/-0.72; cerebral cortices: BP=1.05+/-0.45). Despite the low brain uptake of [11C]AcL703, regional distributions were in good agreement with our previous studies of rodents. This indicates the possibility of in vivo evaluation of NMDA receptors using PET with [11C]AcL703 in living human brain.

When humans manipulate a control device under operational rules, with the goal of indirectly controlling a remote tool to achieve a desired outcome, they may rely on the power of internal representation to organize individual moves of the controller and tool into a set of sequences by mapping the motor space among hand, controller and tool. We recently used functional brain imaging (PET) to investigate activations in monkey brain associated with joystickcontrolled remote operation of a shovel to obtain food. Activated areas included the prefrontal cortex, posterior parietal cortex and cerebellum, regardless of the rules relating movements of the joystick to those of the shovel (Obayashi et al., 2004). If those areas are engaged in the mental manipulation of internal representation, then we should expect brain activity in the same regions during any similar remote operation, even with different controllers and/or operational rules. To address the above hypothesis in the current study, we used PET to measure regional cerebral blood flow (rCBF) of two monkeys during a task in which they were required to control a shovel remotely (to fetch a food pellet) by manipulating dual dials. Compared to unplanned movement of the dials, the active dual-dial operation was associated with robust activation of the prefrontal cortex, higher-order motor cortex, posterior parietal cortex and cerebellum, quite similar to that observed during remote operation with a joystick. The present study suggests that monkeys might be able to organize abstract sequential operations according to learned rules, and perhaps indeed to have insight into the nature of the causal relationships, implying the existence of a relatively sophisticated system of internal representation in the absence of language. The fact that the present results are consistent with our previous PET studies strengthens the view that the underlying mechanism for implicit manipulation of internal representations may involve a cerebro-cerebellar neural circuit including the frontal and parietal cortex.

N-(5-Fluoro-2-phenoxyphenyl)-N-(2-(18)F-fluoroethyl-5-methoxybenzyl)acetamide ((18)F-FEDAA1106) is a potential PET ligand with highly selective and specific binding to peripheral benzodiazepine receptor (PBR). It has been reported that the regional density of PBR in the brain is increased in several neurodegenerative and psychiatric disorders. Thus, a reliable tracer method for evaluating PBR would be of use clinically and for research. To our knowledge, this is the first study to investigate the (18)F-FEDAA1106 binding to PBR in living human brain by PET. We also aimed to evaluate various analytic methods to quantify the density of PBR.PET studies with (18)F-FEDAA1106 were performed on 7 healthy men. Volumes of interest (VOIs) were drawn on PET images. In each VOI, binding potential (BP) was calculated by nonlinear least-squares (NLS) fitting based on the 2-tissue compartment model, and the distribution volume (DV) was also estimated by NLS, Logan plot, and multilinear analysis (MA) methods. To estimate errors in calculation of BP and DV, simulation studies were also performed.The DVs estimated with each of the methods were significantly correlated. There was also significant correlation between BP with NLS and DV with NLS, Logan plot, or MA. But the interindividual differences in the distribution volume of the free and nonspecific binding compartment (K(1)/k(2)) were relatively large. In a simulation study, variation of the DV estimated by Logan plot was relatively small, but it was underestimated as the noise increased. By MA, the bias of DV was smaller, but the variation of DV was larger than by Logan plot. Within a 3% noise level, there was almost no difference between Logan plot and MA in both bias and variation. DVs estimated by both Logan plot and MA were underestimated by 10%-20%. Although the variation of DV was larger by NLS than by Logan plot, it was small enough in the noise level of VOI analysis, and the bias of DV was 0%-2%.The simulation studies indicated that NLS is a suitable method for the estimation of (18)F-FEDAA1106 binding to PBRs.

Positron Emission Tomography (PET) allows in vivo visualization of the expression and function of protein using a radioligand. Quantitative analysis of serotonin transporter, receptors, and the function of P-Glycoprotein has been performed in living human brains. Furthermore, the relationship between the phenotype of those proteins and their genetic polymorphism has also been investigated. Regarding the effect of antipsychotics on dopamine D2 receptor, occupancy and its time-course have been measured in a living body using PET. This approach can provide in vivo pharmacological evidences of antipsychotics and establish a rational therapeutic strategy. PET is a powerful tool not only in the field of brain research but also drug discovery and individual medicine.

Japan Young Psychiatrists Organization was founded in 2002. The Course for Academic Development of Psychiatrists (CADP) held in 2001 was the momentum to establish JYPO. CADP is the course designed by Professor N. Sartorius for the purpose of developing professional and leadership skills of young psychiatrists. From then, JYPO have continued to hold CADP annually. Now we JYPO welcome the participants of CADP from overseas. We aim to introduce the detailed contents of CADP to the Asian colleague and encourage them to participate in CADP.