Low computational-cost cell detection method for calcium imaging data.

The rapid progress of calcium imaging techniques has reached a point where the activity of thousands to tens of thousands of cells can be recorded simultaneously with single-cell resolution in a field-of-view (FOV) of about ten mm2. Consequently, there is a pressing need for developing automatic cell detection methods for large-scale image data. Several research groups have proposed automatic cell detection algorithms. Almost all algorithms can solve large-scale optimization problems for data, including hundreds of cells recorded from a conventional FOV at a resolution of 512 × 512 pixels, but the solution becomes more difficult as the data size increases beyond that. To handle large-scale data acquired with the latest large FOV microscopes, we propose a method called low computational cost cell detection (LCCD) that is based on filtering and thresholding. We compared LCCD with two other methods, constrained non-negative matrix factorization (CNMF) and Suite2P. We found that LCCD makes it possible to detect cells in artificial and actual data showing a high number density of cells within a shorter time and with an accuracy comparable to or better than those of CNMF and Suite2P. Moreover, LCCD succeeded in detecting more than 20,000 active cells from data acquired with the latest microscopy, called FASHIO-2PM, with a FOV of 3.0 mm × 3.0 mm.

Presence of Three-Dimensional Sound Field Facilitates Listeners' Mood, Felt Emotion, and Respiration Rate When Listening to Music.

Many studies have investigated the effects of music listening from the viewpoint of music features such as tempo or key by measuring psychological or psychophysiological responses. In addition, technologies for three-dimensional sound field (3D-SF) reproduction and binaural recording have been developed to induce a realistic sensation of sound. However, it is still unclear whether music listened to in the presence of 3D-SF is more impressive than in the absence of it. We hypothesized that the presence of a 3D-SF when listening to music facilitates listeners' moods, emotions for music, and physiological activities such as respiration rate. Here, we examined this hypothesis by evaluating differences between a reproduction condition with headphones (HD condition) and one with a 3D-SF reproduction system (3D-SF condition). We used a 3D-SF reproduction system based on the boundary surface control principle (BoSC system) to reproduce a sound field of music in the 3D-SF condition. Music in the 3D-SF condition was binaurally recorded through a dummy head in the BoSC reproduction room and reproduced with headphones in the HD condition. Therefore, music in the HD condition was auditorily as rich in information as that in the 3D-SF condition, but the 3D-sound field surrounding listeners was absent. We measured the respiration rate and heart rate of participants listening to acousmonium and pipe organ music. The participants rated their felt moods before and after they listened to music, and after they listened, they also rated their felt emotion. We found that the increase in respiration rate, the degree of decrease in well-being, and unpleasantness for both pieces in the 3D-SF condition were greater than in the HD condition. These results suggest that the presence of 3D-SF enhances changes in mood, felt emotion for music, and respiration rate when listening to music.

Calibration of Consonant Perception to Room Reverberation.

Purpose We examined how consonant perception is affected by a preceding speech carrier simulated in the same or a different room, for different classes of consonants. Carrier room, carrier length, and carrier length/target room uncertainty were manipulated. A phonetic feature analysis tested which phonetic categories are influenced by the manipulations in the acoustic context of the carrier. Method Two experiments were performed, each with nine participants. Targets consisted of 10 or 16 vowel-consonant (VC) syllables presented in one of two strongly reverberant rooms, preceded by a multiple-VC carrier presented in either the same room, a different reverberant room, or an anechoic room. In Experiment 1, the carrier length and the target room randomly varied from trial to trial, whereas in Experiment 2, they were fixed within a block of trials. Results Overall, a consistent carrier provided an advantage for consonant perception compared to inconsistent carriers, whether in anechoic or differently reverberant rooms. Phonetic analysis showed that carrier inconsistency significantly degraded identification of the manner of articulation, especially for stop consonants and, in one of the rooms, also of voicing. Carrier length and carrier/target uncertainty did not affect adaptation to reverberation for individual phonetic features. The detrimental effects of anechoic and different reverberant carriers on target perception were similar. Conclusions The strength of calibration varies across different phonetic features, as well as across rooms with different levels of reverberation. Even though place of articulation is the feature that is affected by reverberation the most, it is the manner of articulation and, partially, voicing for which room adaptation is observed.

Significant Solvent Effect on Reactivity of Oxoiron(IV) Porphyrin π-Cation Radical Complex: Activation in n-Alkane Solvent.

The solvent effect on the reactivity of high-valent metal oxo complexes has not been studied well, because of their solubility and stability. We synthesize oxoiron(IV) porphyrin π-cation radical complexes (1-CompI and 2-CompI) having the n-hexyl side chains. 1-CompI and 2-CompI are soluble in various solvents, even in hexane, at -80 °C, allowing for the study of their reactivity in various organic solvents. We show that pentane, hexane, heptane, and tert-butyl methyl ether significantly increase the reactivity of 1-CompI and 2-CompI, but dichloromethane, the most frequently used solvent in previous studies, is the worst for increasing the reactivity among the solvents. 1H NMR and EPR spectroscopies show no significant change in hexane, but the Eyring plots for the epoxidation reactions indicate that the entropies of activation in n-alkane solvents are larger than those in dichloromethane. The observed solvent effect can be rationalized with reorganization energy of the solvent in the reaction.

Effect of supplementation with the reduced form of coenzyme Q10 on semen quality and antioxidant status in dogs with poor semen quality: Three case studies.

Oxidative stress owing to an imbalance between reactive oxygen species and antioxidants, such as coenzyme Q10 (CoQ10), is a major contributor to male infertility. We investigated the effects of the reduced form of CoQ10 (ubiquinol) supplementation on semen quality in dogs with poor semen quality. Three dogs received 100 mg of ubiquinol orally once daily for 12 weeks. Semen quality, serum testosterone, and seminal plasma superoxide dismutase (SOD) activity were examined at 2-week intervals from 2 weeks before ubiquinol supplementation to 4 weeks after the treatment. Ubiquinol improved sperm motility, reduced morphologically abnormal sperm, and increased seminal plasma SOD activity; however, it had no effect on testosterone level, semen volume, and sperm number. Ubiquinol supplementation could be used as a non-endocrine therapy for infertile dogs.

meso-Substitution Activates Oxoiron(IV) Porphyrin π-Cation Radical Complex More Than Pyrrole-ß-Substitution for Atom Transfer Reaction.

There have been two known categories of porphyrins: a meso-substituted porphyrin like meso-tetramesitylporphyrin (TMP) and a pyrrole-ß-substituted porphyrin like native porphyrins and 2,7,12,17-tetramethyl-3,8,13,18-tetramesitylporphyrin (TMTMP). To reveal the chemical and biological function of native hemes, we compare the reactivity of the oxoiron(IV) porphyrin π-cation radical complex (Compound I) of TMP (TMP-I) with that of TMTMP (TMTMP-I) for epoxidation, hydrogen abstraction, hydroxylation, sulfoxidation, and demethylation reactions. Kinetic analysis of these reactions indicated that TMP-I is much more reactive than TMTMP-I when the substrate is not sterically bulky. However, as the substrate is sterically bulkier, the difference of the reactivity between TMP-I and TMTMP-I becomes smaller, and the reactivity of TMP-I is comparable to that of TMTMP-I for a sterically hindered substrate. Since the redox potential of TMP-I is almost the same as that of TMTMP-I, we conclude that TMP-I is intrinsically more reactive than TMTMP-I for these atom transfer reactions, but the steric effect of TMP-I is stronger than that of TMTMP-I. This is contrary to the previous result for the single electron transfer reaction: TMTMP-I is faster than TMP-I. DFT calculations indicate that the orbital energies of the Fe═O moiety for TMTMP-I are higher than those for TMP-I. The difference in steric effect between TMP-I and TMTMP-I is explained by the distance from the mesityl group to the oxo ligand of Compound I. Significance of the pyrrole-ß-substituted structure of the hemes in native enzymes is also discussed on the basis of this study.

Comprehensive evaluation of antioxidant effects of Japanese Kampo medicines led to identification of Tsudosan formulation as a potent antioxidant agent.

Oxidative stress due to the overproduction of reactive oxygen species plays an important role in the pathogenesis of various diseases. In the present study, we comprehensively evaluated the antioxidant activities of 147 oral formulations of Japanese traditional herbal medicines (Kampo medicines), representing the entire panel of oral Kampo medicines listed in the Japanese National Health Insurance Drug List, using in vitro radical scavenging assays, including the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity assay, the superoxide anion scavenging activity assay, and the oxygen radical absorption capacity assay. Three of the formulations tested, namely, Tsudosan, Daisaikoto, and Masiningan, showed the most potent in vitro antioxidant activities and were selected for further investigation of their intracellular and in vivo antioxidant effects. The results of the 2',7'-dichlorodihydrofluorescin diacetate assay demonstrated that all three Kampo medicines significantly inhibited hydrogen peroxide-induced oxidative stress in human hepatocellular liver carcinoma HepG2 cells. In addition, Tsudosan significantly increased the serum biological antioxidant potential values when orally administrated to mice, indicating that it also had in vivo antioxidant activity. The potent antioxidant activity of Tsudosan may be one of the mechanisms closely correlated to its clinical usage against blood stasis.

(E)-,(Z)-parallel preparative methods for stereodefined ß,ß-diaryl- and α,ß-diaryl-α,ß-unsaturated esters: application to the stereocomplementary concise synthesis of zimelidine.

Parallel and practical methods for the preparation of both (E)- and (Z)-ß-aryl(1)-ß-aryl(2)-α,ß-unsaturated esters 1 and (E)- and (Z)-α-aryl(1)-ß-aryl(2)-α,ß-unsaturated esters 2 are described. These methods involve accessible, robust, stereocomplementary N-methylimidazole (NMI)-mediated enol tosylations (14 examples, 70-99% yield), as well as stereoretentive Suzuki-Miyaura cross-couplings (36 examples, 64-99% yield). The highlighted feature of the present protocol is the use of parallel and stereocomplementary approaches to obtain highly (E)- and (Z)-pure products 1 and 2 by utilizing sequential enol tosylations and cross-coupling reactions. An expeditious and parallel synthesis of (E)- and (Z)-zimelidine (3), which is a highly representative selective serotonin reuptake inhibitor (SSRI), was performed by utilizing the present methods.

Motor area activity for action-related and nonaction-related sounds in a three-dimensional sound field reproduction system.

The motor cortical area is often activated to auditory stimuli in the human brain. In this study, we examined whether the motor area shows differential activation for action-related and nonaction-related sounds and whether it is susceptible to the quality of the sounds. A three-dimensional sound field recording and reproduction system based on the boundary surface control principle (BoSC system) was used for this purpose. We measured brain activity during hearing action-related or nonaction-related sounds with electroencephalography using mu rhythm suppression (mu-suppression) as an index of motor cortical activation. The results showed that mu-suppression was observed when the participant heard action-related sounds, but it was not evident when hearing nonaction-related sounds. Moreover, this suppression was significantly larger in the 3D sound field (62-ch loudspeaker condition), which generates a more realistic sound field, than in the 1-ch loudspeaker condition. Our results indicate that the motor area was indeed activated for action-related sounds and that its activation was enhanced with a 3D realistic sound field. We discuss our findings in relation to the mirror neuron system and the possibility of using its activity as an objective measure that reflects the subjective sense of reality in various virtual reality settings when interacting with others.

Neural Basis of the Time Window for Subjective Motor-Auditory Integration.

Temporal contiguity between an action and corresponding auditory feedback is crucial to the perception of self-generated sound. However, the neural mechanisms underlying motor-auditory temporal integration are unclear. Here, we conducted four experiments with an oddball paradigm to examine the specific event-related potentials (ERPs) elicited by delayed auditory feedback for a self-generated action. The first experiment confirmed that a pitch-deviant auditory stimulus elicits mismatch negativity (MMN) and P300, both when it is generated passively and by the participant's action. In our second and third experiments, we investigated the ERP components elicited by delayed auditory feedback for a self-generated action. We found that delayed auditory feedback elicited an enhancement of P2 (enhanced-P2) and a N300 component, which were apparently different from the MMN and P300 components observed in the first experiment. We further investigated the sensitivity of the enhanced-P2 and N300 to delay length in our fourth experiment. Strikingly, the amplitude of the N300 increased as a function of the delay length. Additionally, the N300 amplitude was significantly correlated with the conscious detection of the delay (the 50% detection point was around 200 ms), and hence reduction in the feeling of authorship of the sound (the sense of agency). In contrast, the enhanced-P2 was most prominent in short-delay (≤200 ms) conditions and diminished in long-delay conditions. Our results suggest that different neural mechanisms are employed for the processing of temporally deviant and pitch-deviant auditory feedback. Additionally, the temporal window for subjective motor-auditory integration is likely about 200 ms, as indicated by these auditory ERP components.

Recalibration of subjective simultaneity between self-generated movement and delayed auditory feedback.

Temporal contingency between motor commands and corresponding auditory feedback is crucial for perception of self-generated sound as well as external auditory events. The present study examined whether delay detection of self-generated sound was affected by the range of delayed auditory feedback used during the experiment. Participants pressed a button with their right index finger and judged whether auditory feedback was delayed compared with the sensation of finger movement. The range of auditory feedback delay was varied across conditions. To calculate the delay detection threshold (DDT), that is, the point at which the delay detection rate was 50%, we fitted a logistic function to the delay-detection probability curve. The DDT was significantly different across conditions (Tukey-Kramer's honestly significant difference test, P<0.01). Specifically, the DDT became longer as the mean delay of the range increased. However, this shift was not observed for the delay range with a minimum delay greater than 250 ms. We propose that the subjective simultaneity of auditory feedback and self-body movement is, to some extent, automatically recalibrated toward the mean delay of the delay range used in the experiment.

Evaluation of the apnea-hypopnea index determined by the S8 auto-CPAP, a continuous positive airway pressure device, in patients with obstructive sleep apnea-hypopnea syndrome.

OBJECTIVE: Continuous positive airway pressure (CPAP) has been established as an effective treatment for obstructive sleep apnea-hypopnea syndrome (OSAHS). Recently, several auto-CPAP devices that can detect upper airway obstructive events and provide information about residual events while patients are on CPAP have come into clinical use. The purpose of this study was to compare the apnea-hypopnea index (AHI) determined by the S8 auto-CPAP device with the AHI derived by polysomnography in patients with OSAHS. METHOD: Consecutive patients with OSAHS titrated on S8 auto-CPAP were included. The correlation between AHI determined by manual scoring (AHI-PSG) and by S8 (AHIS8) during an overnight in-hospital polysomnogram with the patient on CPAP was assessed. Furthermore, the apnea index (Al) and the hypopnea index (HI) were evaluated separately. RESULTS: Seventy patients with OSAHS (94% men) were enrolled. The mean AHI on the diagnostic study was 51.9 +/- 2.4. During the titration, this device markedly suppressed the respiratory events (AHI-PSG, 4.2 +/- 0.4; AI, 1.9 +/- 0.3; HI, 2.3 +/- 0.3). On the other hand, the AHI-S8 was 9.9 +/- 0.6 (AI-S8, 2.4 +/- 0.3; HI-S8, 7.5 +/- 0.4). There was a strong correlation between the overall AHI-PSG and the AHI-S8 (r = 0.85, p < 0.001), with a stronger correlation in the apnea component AI-PSG and the AI-S8 (r = 0.93, p < 0.001), whereas there was a weaker correlation between the HI-PSG and the HI-S8 (r = 0.67, p <0.001). CONCLUSIONS: Using the same airflow signals as those of the CPAP device, a strong correlation between the AHI-PSG and the AHI-S8 was observed. However, the correlation was weakened when the analysis was limited to the HI.

General, robust, and stereocomplementary preparation of alpha,beta-disubstituted alpha,beta-unsaturated esters.

An (E)- and (Z)-stereocomplementary preparative method for alpha,beta-disubstituted alpha,beta-unsaturated esters is performed via three general and robust reaction sequences: (i) Ti-Claisen condensation (formylation) of esters to give alpha-formyl esters (12 examples, 60-99%), (ii) (E)- and (Z)-stereocomplementary enol p-toluenesulfonylation (tosylation) using TsCl-N-methylimidazole (NMI)-Et(3)N and LiOH (24 examples, 82-99%), and (iii) stereoretentive Suzuki-Miyaura cross-coupling (18 examples, 64-96%).

General, robust, and stereocomplementary preparation of beta-ketoester enol tosylates as cross-coupling partners utilizing TsCl-N-methylimidazole agents.

We have developed a general, robust, and cost-effective method for the (E)- or (Z)-stereocomplementary enol tosylation of beta-ketoesters using TsCl- N-methylimidazole (NMI)-Et3N or LiOH. TsCl coupled with NMI formed a highly reactive N-sulfonylammonium intermediate. Stereocongested secondary alcohols were smoothly sulfonylated using Ts(Ms)Cl-NMI-Et3N. beta-Ketoesters underwent (E)-selective tosylation using TsCl-NMI-Et3N and (Z)-selective tosylation using TsCl-NMI-LiOH (total of 23 examples; 60%-99% yield). Stereoretentive Negishi and Sonogashira couplings using enol tosylates proceeded successfully to give trisubstituted alpha,beta-unsaturated esters.

The effects of host-feeding on synovigenic egg development in an endoparasitic wasp, Itoplectis naranyae.

Many adult parasitoids feed on host insects, a behavior known as host-feeding. Feeding on hosts is essential to maximizing female fecundity, but its contribution to reproduction varies from species to species. The relationship between fecundity and host-feeding was examined in the solitary endoparasitoid wasp Itoplectis naranyae Ashmead, (Hymenoptera: Ichneumonidae) to assess the significance of host-feeding in female reproduction. Adult female wasps did not respond to hosts when they were 0-1 days old, but subsequently increased their oviposition and host-feeding activities with increasing female age. While newly emerging females had no mature eggs in their ovary, the number of mature eggs increased rapidly thereafter, a process termed synovigeny. Female wasps were capable of maturing eggs without host-feeding, and this suggested that they produced a certain portion of eggs from nutritional reserves that had been stored during the larval stage. Behavioral observations revealed that I. naranyae was a destructive host-feeder as the host was damaged during feeding. Female fecundity was greater in females that had previously fed on hosts than those did not, indicating that host-feeding was involved in egg production. There was a time-delayed relation between host-feeding events and additional egg production; at least 3 days were required to mature eggs from nutrients gained via feeding on hosts. The significance of host-feeding in I. naranyae reproduction is discussed in the context of its life history traits.