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1.
Nat Commun ; 15(1): 2884, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38570488

ABSTRACT

Increasing evidence has revealed the large-scale nonstationary synchronizations as traveling waves in spontaneous neural activity. However, the interplay of various cell types in fine-tuning these spatiotemporal patters remains unclear. Here, we performed comprehensive exploration of spatiotemporal synchronizing structures across different cell types, states (awake, anesthesia, motion) and developmental axis in male mice. We found traveling waves in glutamatergic neurons exhibited greater variety than those in GABAergic neurons. Moreover, the synchronizing structures of GABAergic neurons converged toward those of glutamatergic neurons during development, but the evolution of waves exhibited varying timelines for different sub-type interneurons. Functional connectivity arises from both standing and traveling waves, and negative connections can be elucidated by the spatial propagation of waves. In addition, some traveling waves were correlated with the spatial distribution of gene expression. Our findings offer further insights into the neural underpinnings of traveling waves, functional connectivity, and resting-state networks, with cell-type specificity and developmental perspectives.


Subject(s)
GABAergic Neurons , Male , Mice , Animals
2.
J Chem Phys ; 157(4): 044302, 2022 Jul 28.
Article in English | MEDLINE | ID: mdl-35922342

ABSTRACT

The tantalum anion has the most complicated photoelectron spectrum among all atomic anions of transition elements, which was the main obstacle to accurately measure its electron affinity via the generic method. The latest experimental value of the electron affinity of Ta was 0.323(12) eV, reported by Feigerle et al. [J. Chem. Phys. 74, 1580 (1981)]. In the present work, we report the high-resolution photoelectron spectroscopy of Ta- via the slow-electron velocity-map imaging method combined with a cryogenic ion trap. The electron affinity of Ta was measured to be 2652.38(17) cm-1 or 0.328 859(23) eV. Three excited states 5D1, 3P0, and 5D2 of Ta- were observed, and their energy levels were determined to be 1169.64(17) cm-1 for 5D1, 1735.9(10) cm-1 for 3P0, and 2320.1(20) cm-1 for 5D2 above the ground state 5D0, respectively.

3.
J Headache Pain ; 23(1): 15, 2022 Jan 24.
Article in English | MEDLINE | ID: mdl-35073844

ABSTRACT

BACKGROUND: As the relay centre for processing sensory information, the thalamus may involve in the abnormal sensory procedure caused by cortical spreading depression (CSD). However, few studies have focused on the transient response of thalamus during CSD. Our study aimed to investigate the neuronal activity of mouse thalamus ventral posteromedial nucleus (VPM) during CSD by in vivo micro-endoscopic fluorescence imaging of the genetic calcium probe GCaMP6s expressed in excitatory glutamatergic neurons. METHODS: Thirty-four transgenic VGluT2-GCaMP6s mice were used in the experiments. An endoscope was inserted into the VPM for image acquisition. CSD was induced by KCl topically applied unilaterally on the cranial dura. Data were acquired in awake (ipsilateral or contralateral VPM, saline instead of KCl, MK-801 treatment) and anaesthetized (isoflurane, pentobarbital) states. Statistical analysis was performed using analysis of variance (ANOVA) by SPSS. RESULTS: We found that after CSD induced in ipsilateral motor cortex, the neuronal activity increased and propagated from the posterior-lateral to the anterior-medial part of the VPM with an average speed of 3.47 mm/min. When CSD was induced in visual cortex, the response propagated in opposite direction, from the anterior-medial to the posterior-lateral part of the VPM. Aanaesthetics resulted in the suppression of VPM activation induced by CSD. No significant VPM activation was detected when CSD was induced in contralateral cortex or KCl was replaced by saline. When 5 mM MK-801 was applied to the dura, the electrode failed to record the DC shift of CSD, and there was no significant VPM activation after KCl application. CONCLUSION: CSD induced propagating activation of the ipsilateral VPM in awake mice. The response might correlate to the cortical location where CSD was induced and might be affected by anaesthetics. No significant VPM activation was detected in saline and mk801 experiment results indicated that this VPM activation is due to CSD rather than mouse motion or direct effect of the KCl applying to the intact dura. This finding suggests the potential involvement of thalamus in the migraine auras.


Subject(s)
Cortical Spreading Depression , Animals , Mice , Mice, Transgenic , Thalamus , Ventral Thalamic Nuclei , Wakefulness
4.
Nutrients ; 13(11)2021 Nov 16.
Article in English | MEDLINE | ID: mdl-34836365

ABSTRACT

Inconsistent conclusions from infant sleep and feeding studies may influence parents feeding-related decisions. This study aimed to systematically review the existing literature on infant sleep and its relation to the timing of introduction to complementary foods and type of milk feeding to better understand their role(s) in infant sleep. Cohort, longitudinal, cross-sectional studies, and controlled trials were identified using online searches of five databases up to April 2020. Twenty-one articles with a total of 6225 infants under 12 months-of-age were eligible. Exclusively breastfed infants (≤6 months-of-age) had a greater number of night wakings, but most studies (67%) reported no difference in night-time and 24 h sleep duration compared to formula-fed infants. However, after 6 months-of-age, most studies (>65%) reported breastfed infants to sleep less in the night-time and over 24 h compared to formula-fed infants. Furthermore, studies reported no association between the timing of introduction to complementary foods and infant sleep duration (<12 months-of-age). Future studies using standardized methodologies and definitions, transdisciplinary expertise, and longitudinal design are required to better understand the complex role of feeding on sleep.


Subject(s)
Infant Food/statistics & numerical data , Infant Formula/statistics & numerical data , Infant Nutritional Physiological Phenomena/physiology , Milk/statistics & numerical data , Sleep/physiology , Animals , Breast Feeding/statistics & numerical data , Female , Humans , Infant , Male , Milk, Human , Time Factors
5.
J Chem Phys ; 154(7): 074303, 2021 Feb 21.
Article in English | MEDLINE | ID: mdl-33607888

ABSTRACT

Gold fluoride is a very unique species. In this work, we reported the resonant photodetachment spectra of cryogenically cooled AuF- via the slow-electron velocity-map imaging method. We determined the electron affinity of AuF to be 17 976(8) cm-1 or 2.2287(10) eV. We observed a dipole-bound state with a binding energy of 24(8) cm-1, a valence excited state with a binding energy of 1222(11) cm-1, and a resonant state with an energy of 814(12) cm-1 above the photodetachment threshold. An unusual vibrational transition with Δn = -3 was observed in the autodetachment from the dipole-bound state. Moreover, two excited states of neutral AuF were recognized for the first time, located at 13 720(78) cm-1 and 16 188(44) cm-1 above the AuF ground state.

6.
Qual Life Res ; 29(9): 2375-2381, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32253669

ABSTRACT

PURPOSE: Social isolation in older adults is a major public health problem and associated with increased morbidity and mortality. There are limited data on the association between social isolation and physical function including gait speed. Hence, this study is to determine the prevalence of social isolation and its association with gait speed, frailty, cognition, depression and comorbidities amongst community-dwelling older adults. METHODS: Social isolation, depression, frailty and perceived general health were assessed using 6-item Lubben Social Network Scale (LSNS-6), Geriatric Depression Scale (GDS), FRAIL scale and EuroQol EQ-5D-5L questionnaire which includes EQ Visual Analogue Scale (EQ-VAS), respectively. Cognition was assessed using the Chinese Mini Mental State Examination (cMMSE), while physical performance test included gait speed and short physical performance battery test. Binary logistic regression was performed to determine the influence of socio-demographic, medical, functional and cognitive variables on social isolation. RESULTS: Out of 202 participants, 27.7% were robust, 66.8% of participants were pre-frail, and 5.4% of participants were frail. Almost half (45.5%, n = 92) of the participants were found to be at risk of social isolation. A poor social network was negatively associated with mean gait speed (OR = 0.674, CI 0.464-0.979, p = 0.039), EQ-VAS (OR = 0.561, CI 0.390-0.806, p < 0.01) and cMMSE (OR = 0.630, 95% CI 0.413-0.960, p = 0.032). CONCLUSION: Almost half of older adults in the community are at risk of social isolation with a very significant association with gait speed, cMMSE and EQ-VAS scores.


Subject(s)
Independent Living/psychology , Quality of Life/psychology , Social Isolation/psychology , Walking Speed/physiology , Aged , Aged, 80 and over , Cognition/physiology , Comorbidity , Cross-Sectional Studies , Depression/psychology , Female , Frail Elderly/psychology , Frailty , Geriatric Assessment , Humans , Logistic Models , Male , Mental Status and Dementia Tests , Prevalence , Psychometrics , Surveys and Questionnaires
7.
J Chem Phys ; 152(11): 114303, 2020 Mar 21.
Article in English | MEDLINE | ID: mdl-32199425

ABSTRACT

We report the high-resolution photoelectron spectra of negative gallium anions obtained via the slow-electron velocity-map imaging method. The electron affinity of Ga is determined to be 2429.07(12) cm-1 or 0.301 166(14) eV. The fine structures of Ga are well resolved: 187.31(22) cm-1 or 23.223(27) meV for 3P1 and 502.70(28) cm-1 or 62.327(35) meV for 3P2 above the ground state 3P0, respectively. The photoelectron angular distribution for photodetachment from Ga-(4s24p2 3P0) to Ga(4s25s 2S1/2) is measured. An unexpected perpendicular distribution instead of an isotropic distribution is observed, which is due to a resonance near 3.3780 eV.

8.
J Chem Phys ; 152(3): 034302, 2020 Jan 21.
Article in English | MEDLINE | ID: mdl-31968957

ABSTRACT

The latest electron affinity value of an iridium atom is 1.564 36(15) eV, determined via a method based on the Wigner threshold law by Bilodeau and co-workers. However, they observed a significant deviation from the Wigner threshold law in the threshold photodetachment experiment. To address this dilemma, we conducted high-resolution photoelectron spectroscopy of Ir- via the slow-electron velocity-map imaging method in combination with an ion trap. The electron affinity of Ir was measured to be 12 614.97(9) cm-1 or 1.564 057(11) eV. We find that the Wigner threshold law is still valid for the threshold photodetachment of Ir- through a p-wave fitting of the photodetachment channel Ir-5d86s23F4→Ir5d86sb4F9/2. The photoelectron angular distributions of photodetachment channels Ir-5d86s23F4→Ir5d76s2a4F9/2 and Ir-5d86s23F4→Ir5d86sb4F9/2 were also investigated. The behavior of anisotropy parameter ß indicates a strong interaction between the two channels. Moreover, the energy level 3P2 of Ir-, which was not observed in the previous works, was experimentally determined to be 4163.24(16) cm-1 above the ground state.

9.
Phys Rev Lett ; 123(20): 203002, 2019 Nov 15.
Article in English | MEDLINE | ID: mdl-31809070

ABSTRACT

Laser cooling is a well-established technique for the creation of ensembles of ultracold neutral atoms or positive ions. This ability has opened many exciting new research fields over the past 40 years. However, no negatively charged ions have been directly laser cooled because a cycling transition is very rare in atomic anions. Efforts of more than a decade currently have La^{-} as the most promising candidate. We report on experimental and theoretical studies supporting Th^{-} as a new promising candidate for laser cooling. The measured and calculated electron affinities of Th are, respectively, 4901.35(48) cm^{-1} and 4832 cm^{-1}, or 0.607 690(60) and 0.599 eV, almost a factor of 2 larger than the previous theoretical value of 0.368 eV. The ground state of Th^{-} is determined to be 6d^{3}7s^{2} ^{4}F_{3/2}^{e} rather than 6d^{2}7s^{2}7p ^{4}G_{5/2}^{o}. The consequence of this is that there are several strong electric dipole transitions between the bound levels arising from configurations 6d^{3}7s^{2} and 6d^{2}7s^{2}7p in Th^{-}. The potential laser-cooling transition is ^{2}S_{1/2}^{o}↔^{4}F_{3/2}^{e} with a wavelength of 2.6 µm. The zero nuclear spin and hence lack of hyperfine structure in Th^{-} reduces the potential complications in laser cooling as encountered in La^{-}, making Th^{-} a new and exciting candidate for laser cooling.

10.
J Phys Chem Lett ; 10(4): 702-706, 2019 Feb 21.
Article in English | MEDLINE | ID: mdl-30698969

ABSTRACT

Recent advances in experimental techniques have made it relatively easy to prepare reactant cations in well-defined states of electronic excitation. Extensive studies on the role of excited states in the cation-neutral reactions have contributed significantly to our understanding of reaction kinetics and dynamics. The excited states are often more reactive than the ground state. However, the reactions involving the excited atomic anion are very rare because the negative ions usually have no bound excited states. In the present work, we report the state-specific reaction of Pd anions with H2. Surprisingly, we observed that the ground-state Pd anions react with H2 10 times faster than the excited Pd anions. The high-level calculations show that the difference is due to the reaction barrier.

11.
J Biophotonics ; 12(1): e201800100, 2019 01.
Article in English | MEDLINE | ID: mdl-29952071

ABSTRACT

Laser speckle contrast imaging (LSCI) is a full-field optical imaging method for monitoring blood flow and vascular morphology with high spatiotemporal resolution. However, due to the limited depth of field of optical system, it is difficult to capture a clear blood flow image with all blood vessels focused, especially for the non-planar biological tissues. In this study, a multi-focus image fusion method based on contourlet transform is introduced to reduce the misfocus effects in LSCI. The experimental results suggest that this method can provide an all-in-focus blood flow image, which is convenient to observe the blood vessels.


Subject(s)
Blood Circulation , Contrast Media , Image Processing, Computer-Assisted , Lasers , Molecular Imaging/methods , Animals , Male , Mice , Mice, Inbred C57BL
12.
J Chem Phys ; 149(13): 134304, 2018 Oct 07.
Article in English | MEDLINE | ID: mdl-30292212

ABSTRACT

The high-resolution photoelectron energy spectra of atomic titanium and its hydride anions were obtained on a slow-electron velocity-map imaging spectrometer equipped with a cold ion trap. The cold ion trap employed in the present measurement was found to be very helpful for reducing the interference from the titanium hydride anions. The electron affinity of Ti was determined to be 609.29(34) cm-1 or 75.54(4) meV. The accuracy was improved by a factor of 350 compared with the previous result. The fine structures of Ti- were clearly resolved: 70.0(12)(4F5/2), 165.2(15)(4F7/2), and 285.2(15) cm-1 (4F9/2) above its ground state 4F3/2. Moreover, the measured electron affinity and vibrational frequency of TiH can be reproduced well using the high level calculations.

13.
Appetite ; 130: 110-116, 2018 11 01.
Article in English | MEDLINE | ID: mdl-30077730

ABSTRACT

The aim of this study was to compare food fussiness, weight, serious choking, and early feeding characteristics in babies following Baby-Led Weaning (BLW) and babies following traditional spoon-feeding (TSF) at 6-7 months of age. The First Foods New Zealand Internet Survey recruited 876 New Zealand caregivers of children aged 6-36 months through social media. Information was collected on food fussiness, infant weight, choking, infant feeding practices, and demographics. Based on infant feeding at 6-7 months of age, participants were described as: TSF (mostly or all adult spoonfed), partial BLW (half adult spoonfed, half self-fed), or full BLW (mostly or all self-fed). A total of 628 (72%), 93 (11%), and 155 (18%) infants followed TSF, partial BLW, and full BLW respectively. Compared to infants following TSF, infants following full BLW had significantly lower food fussiness scores at 6-36 months (difference, 95% CI: -0.37,-0.51 to -0.24). Infants following BLW had been exclusively breastfed for longer (P = 0.019), and at 6-7 months had 1.96 times the odds of consuming red meat, but 0.10 times the odds of consuming iron-fortified infant cereal. Only 21% of BLW participants had received advice from a health professional. In conclusion, many New Zealand parents are following BLW. Benefits associated with BLW included less food fussiness. Although BLW infants were more likely to eat red meat, they were less likely to eat iron-fortified infant cereal. These results suggest the need for studies with biochemical measurement of nutritional status, standardized measurement of weight, and rigorous assessment of diet in infants following BLW.


Subject(s)
Feeding Behavior , Food Preferences , Infant Behavior , Airway Obstruction , Child, Preschool , Female , Humans , Infant , Infant Nutritional Physiological Phenomena , Internet , Male , New Zealand , Surveys and Questionnaires , Weaning
14.
J Chem Phys ; 147(6): 064306, 2017 Aug 14.
Article in English | MEDLINE | ID: mdl-28810756

ABSTRACT

The high-resolution photoelectron spectra of Zr- were obtained via the slow-electron velocity-map imaging method. The electron affinity of Zr was measured to be 3494.67(72) cm-1 or 0.433 283(89) eV. The accuracy has been improved by a factor of 160 compared with the previous result. The fine structures of Zr- were also well resolved: 251.0(37) (4F5/2), 579.6(8) (4F7/2), and 971.7(12) cm-1 (4F9/2) above the ground state 4F3/2.

15.
J Chem Phys ; 145(16): 164307, 2016 Oct 28.
Article in English | MEDLINE | ID: mdl-27802620

ABSTRACT

We report the high-resolution photoelectron spectra of negative vanadium ions obtained via the slow-electron velocity-map imaging method. The electron affinity of V was determined to be 4255.9(18) cm-1 or 0.527 66(20) eV. The accuracy was improved by a factor of 60 with regard to the previous measurement. The fine structure of V- was well resolved: 35.9(11) (5D1), 103.8(12) (5D2), 204.17(74) (5D3), and 330.58(40) cm-1 (5D4) above the ground state 5D0, respectively.

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