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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.
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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.
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Depressão Alastrante da Atividade Elétrica Cortical , Animais , Camundongos , Camundongos Transgênicos , Tálamo , Núcleos Ventrais do Tálamo , VigíliaRESUMO
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.
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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.
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Vida Independente/psicologia , Qualidade de Vida/psicologia , Isolamento Social/psicologia , Velocidade de Caminhada/fisiologia , Idoso , Idoso de 80 Anos ou mais , Cognição/fisiologia , Comorbidade , Estudos Transversais , Depressão/psicologia , Feminino , Idoso Fragilizado/psicologia , Fragilidade , Avaliação Geriátrica , Humanos , Modelos Logísticos , Masculino , Testes de Estado Mental e Demência , Prevalência , Psicometria , Inquéritos e QuestionáriosRESUMO
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-5d86s23F4âIr5d86sb4F9/2. The photoelectron angular distributions of photodetachment channels Ir-5d86s23F4âIr5d76s2a4F9/2 and Ir-5d86s23F4âIr5d86sb4F9/2 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.
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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.
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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}â^{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.
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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.
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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 (Pâ¯=â¯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.
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Comportamento Alimentar , Preferências Alimentares , Comportamento do Lactente , Obstrução das Vias Respiratórias , Pré-Escolar , Feminino , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Internet , Masculino , Nova Zelândia , Inquéritos e Questionários , DesmameRESUMO
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.
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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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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.
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Neurônios GABAérgicos , Masculino , Camundongos , AnimaisRESUMO
BACKGROUND: The introduction of complementary foods during the first year of life influences the diversity of the gut microbiome. How this diversity affects immune development and health is unclear. OBJECTIVE: This study evaluates the effect of consuming kumara or kumara with added banana powder (resistant starch) compared to a reference control at 4 months post randomization on the prevalence of respiratory tract infections and the development of the gut microbiome. METHODS: This study is a double-blind, randomized controlled trial of mothers and their 6-month-old infants (up to n=300) who have not yet started solids. Infants are randomized into one of 3 groups: control arm (C), standard kumara intervention (K), and a kumara intervention with added banana powder product (K+) to be consumed daily for 4 months until the infant is approximately 10 months old. Infants are matched for sex using stratified randomization. Data are collected at baseline (prior to commencing solid food) and at 2 and 4 months after commencing solid food (at around 8 and 10 months of age). Data and samples collected at each timepoint include weight and length, intervention adherence (months 2 and 4), illness and medication history, dietary intake (months 2 and 4), sleep (diary and actigraphy), maternal dietary intake, breast milk, feces (baseline and 4 months), and blood samples (baseline and 4 months). RESULTS: The trial was approved by the Health and Disability Ethics Committee of the Ministry of Health, New Zealand (reference 20/NTA/9). Recruitment and data collection did not commence until January 2022 due to the COVID-19 pandemic. Data collection and analyses are expected to conclude in January 2024 and early 2025, respectively. Results are to be published in 2024 and 2025. CONCLUSIONS: The results of this study will help us understand how the introduction of a specific prebiotic complementary food affects the microbiota and relative abundances of the microbial species, the modulation of immune development, and infant health. It will contribute to the expanding body of research that aims to deepen our understanding of the connections between nutrition, gut microbiota, and early-life postnatal health. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12620000026921; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=378654. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/56772.
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Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/efeitos dos fármacos , Lactente , Método Duplo-Cego , Feminino , Masculino , Fenômenos Fisiológicos da Nutrição do Lactente/imunologia , Musa , Nova Zelândia/epidemiologia , Infecções Respiratórias/imunologia , Infecções Respiratórias/prevenção & controle , Infecções Respiratórias/epidemiologiaRESUMO
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.
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Alimentos Infantis/estatística & dados numéricos , Fórmulas Infantis/estatística & dados numéricos , Fenômenos Fisiológicos da Nutrição do Lactente/fisiologia , Leite/estatística & dados numéricos , Sono/fisiologia , Animais , Aleitamento Materno/estatística & dados numéricos , Feminino , Humanos , Lactente , Masculino , Leite Humano , Fatores de TempoRESUMO
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.
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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.