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1.
Nat Commun ; 15(1): 1786, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413643

RESUMO

Injecting high-energy heavy ions in the electronic stopping regime into solids can create cylindrical damage zones called latent ion tracks. Although these tracks form in many materials, none have ever been observed in diamond, even when irradiated with high-energy GeV uranium ions. Here we report the first observation of ion track formation in diamond irradiated with 2-9 MeV C60 fullerene ions. Depending on the ion energy, the mean track length (diameter) changed from 17 (3.2) nm to 52 (7.1) nm. High resolution scanning transmission electron microscopy (HR-STEM) indicated the amorphization in the tracks, in which π-bonding signal from graphite was detected by the electron energy loss spectroscopy (EELS). Since the melting transition is not induced in diamond at atmospheric pressure, conventional inelastic thermal spike calculations cannot be applied. Two-temperature molecular dynamics simulations succeeded in the reproduction of both the track formation under MeV C60 irradiations and the no-track formation under GeV monoatomic ion irradiations.

2.
JPRAS Open ; 38: 36-47, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37675277

RESUMO

This study evaluated the stability of bilateral sagittal split ramus osteotomy (BSSRO) associated with positional plagiocephaly and temporal and masseter muscles using posteroanterior cephalogram analysis and three-dimensional computed tomography (3D-CT). This retrospective cohort study included 31 patients who underwent BSSRO for mandibular asymmetry. The cranial vault asymmetry index (CVAI) and the cephalic index were used as indicators of positional plagiocephaly. The distance from the vertical reference line to the menton (Me) was measured on posteroanterior cephalograms immediately and 1 year after surgery, and postoperative stability was assessed. Temporal and masseter muscles were constructed from 3D-CT data and their volumes were measured. Simple regression analysis showed a significant correlation between postoperative changes in the vertical reference line to the Me and the CVAI (R = 0.56, p = 0.001), the amount of surgical movement in the vertical reference line to the Me (R = 0.41, p = 0.023), and the variable temporal muscle volume (R = 0.27, p = 0.028). There was no significant correlation between postoperative changes in the vertical reference line to the Me and the cephalic index (R = 0.093, p = 0.62) and variable masseter muscle volume (R = 0.16, p = 0.38). According to multivariate analysis, CVAI (p = 0.003) and amount of surgical movement in the vertical reference line to the Me (p = 0.014) were significant predictors of postoperative change in the vertical reference line to the Me. Positional plagiocephaly and amount of surgical movement influence lateral skeletal stability following BSSRO for mandibular asymmetry.

3.
JAR Life ; 12: 56-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37519417

RESUMO

Background: Exercise, education, and social engagement are critical interventions for older adults for a healthy life expectancy and to improve their physical function. Objective: To conduct a combined exercise and education (CEE) program for improved social engagement and physical function of older adults. Design: Based on a short-term program we conducted in our previous study, in this study, the program was conducted for half the number of participants of the earlier study but for a longer duration. Setting: A community of older adults in Ami, Japan, was the setting of the study. Participants: 23 healthy older adults >65 years living in the community were the participants in the study. Interventions: Five 80-minute sessions conducted once in two weeks comprised 60-min exercise instruction and 20-min educational lectures per session on health. We examined the improvement in physical and social engagement before and after participation. Physical function and health-related questionnaire data were collected before and after the program. Results: Data analysis from 15 participants showed improved physical performance but no effect on social engagement. Conclusions: A higher program frequency, rather than program duration, may be vital to improving exercise performance and social engagement and maximizing the effects of high group cohesion in small groups. Further studies are needed to develop more effective interventions to extend healthy life expectancy.

4.
J Hosp Infect ; 134: 97-107, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36805085

RESUMO

BACKGROUND: The risk factors for coronavirus disease (COVID-19) among healthcare workers (HCWs) might have changed since the emergence of the highly immune evasive Omicron variant. AIM: To compare the risk factors for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among HCWs during the Delta- and Omicron-predominant periods. METHODS: Using data from repeated serosurveys among the staff of a medical research centre in Tokyo, two cohorts were established: Delta period cohort (N = 858) and Omicron period cohort (N = 652). The potential risk factors were assessed using a questionnaire. Acute/current or past SARS-CoV-2 infection was identified by polymerase chain reaction or anti-nucleocapsid antibody tests, respectively. Poisson regression was used to calculate the risk ratio (RR) of infection risk. FINDINGS: The risk of SARS-CoV-2 infection during the early Omicron-predominant period was 3.4-fold higher than during the Delta-predominant period. Neither working in a COVID-19-related department nor having a higher degree of occupational exposure to SARS-CoV-2 was associated with an increased infection risk during both periods. During the Omicron-predominant period, infection risk was higher among those who spent ≥30 min in closed spaces, crowded spaces, and close-contact settings without wearing mask (≥3 times versus never: RR: 6.62; 95% confidence interval: 3.01-14.58), whereas no such association was found during the Delta period. CONCLUSION: Occupational exposure to COVID-19-related work was not associated with the risk of SARS-CoV-2 infection in the Delta or Omicron period, whereas high-risk behaviours were associated with an increased infection risk during the Omicron period.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Japão/epidemiologia , SARS-CoV-2 , Fatores de Risco , Pessoal de Saúde
6.
Health Place ; 76: 102851, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35779324

RESUMO

PURPOSE: According to the social determinants of health framework, income inequality is a potential risk factor for adverse mental health. However, few studies have explored the mechanisms suspected to mediate this relationship. The current study addresses this gap through a mediation analysis to determine if social support and community engagement act as mediators linking neighbourhood income inequality to maternal anxiety and depressive symptoms within a cohort of new mothers living in the City of Calgary, Canada. METHODS: Data collected at three years postpartum from mothers belonging to the All Our Families (AOF) cohort were used in the current study. Maternal data were collected between 2012 and 2015 and linked to neighbourhood socioeconomic data from the 2006 Canadian Census. Income inequality was measured using Gini coefficients derived from 2006 after-tax census data. Generalized structural equation models were used to quantify the associations between income inequality and mental health symptoms, and to assess the potential direct and indirect mediating effects of maternal social support and community engagement. RESULTS: Income inequality was not significantly associated with higher depressive symptoms (ß = 0.32, 95%CI = -0.067, 0.70), anxiety symptoms (ß = 0.11, 95%CI = -0.39, 0.60), or lower social support. Income inequality was not associated with community engagement. For the depression models, higher social support was significantly associated with lower depressive symptoms (ß = -0.13, 95%CI = -0.15, -0.097), while community engagement was not significantly associated with depressive symptoms (ß = 0.059, 95%CI = -0.15, 0.27). Similarly, for the anxiety models, lower anxiety symptoms were significantly associated with higher levels of social support (ß = -0.17, 95%CI = -0.20, -0.13) but not with higher levels of community engagement (ß = 0.14, 95%CI = -0.14, 0.41). CONCLUSION: The current study did not find clear evidence for social support or community engagement mediating the relationship between neighbourhood income inequality and maternal mental health. Future investigations should employ a broader longitudinal approach to capture changes in income inequality, potential mediators, and mental health symptomatology over time.


Assuntos
Análise de Mediação , Saúde Mental , Canadá/epidemiologia , Feminino , Humanos , Renda , Apoio Social , Fatores Socioeconômicos
10.
Int J Tuberc Lung Dis ; 25(9): 725-731, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34802494

RESUMO

OBJECTIVE: To retrospectively evaluate the clinical outcomes of pre-operative endovascular coil embolisation (ECE) for chronic pulmonary aspergillosis (CPA).METHODS: We evaluated surgical patients with CPA between November 2016 and April 2020. Pre-operative ECE for CPA with severe adhesions was selectively performed to reduce intra-operative blood loss. ECE procedures, operative procedures, intra-operative blood loss and complications were evaluated.RESULTS: Twenty-eight patients (21 males and 7 females; median age: 55 years) were included in the study. Of the 28 patients, 8 (28.6%) underwent pre-operative ECE. Technical success rate in pre-operative ECE was 100%. The median time required for ECE procedures was 123 min. The median number of vessels embolised per procedure was 2.5. The median period between embolisation and surgery was 5 days. Major complications were observed in three patients (10.7%). There were no significant differences between patients with and without pre-operative ECE in operative time (284 vs. 365 min, respectively, P = 0.7602) and intra-operative blood loss (294 vs. 228 mL, respectively, P = 0.8987).CONCLUSIONS: Pre-operative ECE for CPA appears to be feasible and safe; however, its role in reducing intra-operative blood loss needs further investigation.


Assuntos
Embolização Terapêutica , Aspergilose Pulmonar , Embolização Terapêutica/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
13.
Sci Rep ; 11(1): 185, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420182

RESUMO

Damaged regions of cylindrical shapes called ion tracks, typically in nano-meters wide and tens micro-meters long, are formed along the ion trajectories in many insulators, when high energy ions in the electronic stopping regime are injected. In most cases, the ion tracks were assumed as consequences of dense electronic energy deposition from the high energy ions, except some cases where the synergy effect with the nuclear energy deposition plays an important role. In crystalline Si (c-Si), no tracks have been observed with any monomer ions up to GeV. Tracks are formed in c-Si under 40 MeV fullerene (C60) cluster ion irradiation, which provides much higher energy deposition than monomer ions. The track diameter decreases with decreasing the ion energy until they disappear at an extrapolated value of ~ 17 MeV. However, here we report the track formation of 10 nm in diameter under C60 ion irradiation of 6 MeV, i.e., much lower than the extrapolated threshold. The diameters of 10 nm were comparable to those under 40 MeV C60 irradiation. Furthermore, the tracks formed by 6 MeV C60 irradiation consisted of damaged crystalline, while those formed by 40 MeV C60 irradiation were amorphous. The track formation was observed down to 1 MeV and probably lower with decreasing the track diameters. The track lengths were much shorter than those expected from the drop of Se below the threshold. These track formations at such low energies cannot be explained by the conventional purely electronic energy deposition mechanism, indicating another origin, e.g., the synergy effect between the electronic and nuclear energy depositions, or dual transitions of transient melting and boiling.

14.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1424-1432, July-Aug. 2020. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1131495

RESUMO

Objetivou-se, com este estudo, avaliar o efeito de dietas com diferentes níveis de energia no consumo de nutrientes, na produção e na composição do leite, no peso corporal e na relação benefício:custo de uma produção de cabras leiteiras. Foram utilizadas nove cabras, distribuídas em quadrado latino triplo 3 x 3. O ensaio teve duração de 60 dias, divididos em três períodos de 20 dias. Avaliaram-se rações completas contendo três níveis de energia: 65%, 70% e 75% de NDT. Os consumos de matéria seca, proteína bruta e matéria mineral foram superiores (P<0,05) nas dietas com maiores níveis de energia em comparação à dieta com 65% de NDT. A produção de leite foi semelhante (P>0,05) nas cabras recebendo dietas contendo 70% e 75% de NDT, todavia foi superior (P<0,05) à produção de leite das cabras recebendo dieta com 65% de NDT. A dieta com 75% de NDT possibilitou maior (P<0,05) peso corporal final, quando comparada com as dietas contendo 65% e 70% de NDT. Não foi observada diferença (P>0,05) para os parâmetros físico-químicos de gordura, lactose, proteína bruta, extrato seco desengordurado, densidade, sais e condutividade do leite. Portanto, cabras alimentadas com níveis de energia entre 70% e 75% de NDT na dieta total aumentam a produção de leite, porém 75% de NDT na dieta proporciona melhor relação benefício:custo, havendo, para cada R$ 1,00 no custo investido na alimentação, R$ 1,52 de retorno financeiro.(AU)


The objective of this study was to evaluate the effect of diets with different energy levels on nutrient intake, milk production and composition, body weight and benefit:cost ratio of a dairy goat production. Nine goats were distributed in a triple 3 x 3 latin square design. The experiment lasted for 60 days, divided into three 20-day periods. Complete rations containing three energy levels were evaluated: 65%, 70% and 75% of TDN. The dry matter intake, crude protein and mineral matter consumption were higher (P <0.05) in the diets with higher levels of energy compared to the diet with 65% of TDN. Milk production was similar (P> 0.05) in goats receiving diets containing 70% and 75% TDN, but these diets produced more milk (P<0.05) than the diet with 65% of TDN. The diet with 75% of TDN allowed a higher (P<0.05) final body weight (P<0.05) when compared to diets containing 65% and 70% TDN. There was no difference (P> 0.05) in the physical-chemical parameters of fat, lactose, crude protein, defatted dry extract, density, salts and conductivity of the milk. Therefore, goats fed with diets of 70% and 75% of TDN in the total diet increased milk production. However, the diet with 75% of TDN provides a better benefit:cost ratio, as for every $ 1.00 in the cost invested, there was $ 1.52 of financial return.(AU)


Assuntos
Animais , Peso Corporal , Cabras , Leite/química , Ração Animal/análise , Fenômenos Químicos
15.
Eur J Neurol ; 27(11): 2117-2124, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32558010

RESUMO

BACKGROUND AND PURPOSE: The detection rate of diffusion-weighted (DWI) hyperintense lesions varies widely in patients with transient global amnesia (TGA). The aim was to examine the association of hyperintense lesions on DWI magnetic resonance imaging (MRI) with patient characteristics, precipitating factors, clinical presentation and MRI settings in patients with TGA. METHODS: In this multicenter retrospective observational study, using the standardized diagnosis entry system of electronic health records of four tertiary medical centers in the Kansai district of Japan, TGA patients (n = 261) who underwent brain MRI within 28 days of onset were examined. When the onset time was unavailable, the discovery time was used. RESULTS: Diffusion-weighted hyperintense lesions were observed in 79 patients (30%). There were no significant differences in age, sex, vascular risk factors, precipitating factors or clinical presentation between patients with and without DWI lesions. The detection rate increased linearly 24 h after onset and then reached a plateau of 60%-80% by 84 h. After 84 h, the detection rate decreased rapidly. In a multivariate logistic regression model, MRI examination 24-84 h after onset (odds ratio 7.00, 95% confidence interval 3.50-13.99) and a thin-slice (≤3 mm) DWI sequence (odds ratio 7.59, 95% confidence interval 3.05-18.88) were independent predictors of DWI lesions. CONCLUSIONS: This study suggests that DWI hyperintense lesions in TGA are not associated with patient characteristics and clinical presentation. Brain MRI examination 24-84 h after onset and thin-slice DWI sequences enhance the detection of DWI lesions in TGA patients.


Assuntos
Amnésia Global Transitória , Amnésia Global Transitória/diagnóstico por imagem , Hipocampo , Humanos , Japão/epidemiologia , Imageamento por Ressonância Magnética
16.
Nanotechnology ; 31(26): 265606, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32155610

RESUMO

We report the elongation of embedded Au nanoparticles (NPs) in three different matrices, i.e. amorphous carbon (a-C), crystalline indium tin oxide (InxSn1-xOz; ITO) and crystalline calcium fluoride (CaF2), under irradiations of 4 MeV C60 + cluster ions and 200 MeV Xe14+ ions. Under 4 MeV C60 cluster irradiation, strong sputtering is induced in CaF2 layer so that the whole the layer was completely lost at a fluence of 5 × 1013 ions cm-2. Au NPs were partly observed in the SiO2, probably due to the recoil implantation. Amorphous carbon (a-C) layer exhibits low sputtering loss even under 4 MeV C60 irradiation. However, the elongation in a-C layer was low. While the ITO layer showed a certain decrease in thickness under 4 MeV C60 irradiation, large elongation of Au NPs was observed under both 4 MeV C60 and 200 MeV Xe irradiation. The ITO layer preserved the crystallinity even after large elongation was induced. This is the first report of the elongation of metal NPs in a crystalline matrix.

17.
Sci Rep ; 10(1): 5, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913300

RESUMO

When realising future fusion reactors, their stationary burning must be maintained and the heat flux to the divertor must be reduced. This essentially requires a stationary internal transport barrier (ITB) plasma with a fast control system. However, the time scale for determining the position of the foot point of an ITB is not clearly understood even though its understanding is indispensable for fast profile control. In this study, the foot point of the electron ITB (eITB) was observed to be reformed at the vicinity of a magnetic island when the island started to form. In addition, the enhanced confinement region was observed to expand during the eITB formation according to the radial movement of the magnetic island toward the outer region. Compared to the time scales of the local heat transport, the faster time scales of the movement of the eITB foot point immediately after island formation (~0.5 ms) suggest the importance of the magnetic island for plasma profile control to maintain stationary burning.

18.
Int J Oral Maxillofac Surg ; 49(5): 686-690, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31601471

RESUMO

Navigation surgery plays an important role in modern craniomaxillofacial surgery, but it is difficult to apply navigation surgery to the mandible, due to its mobility. At present, headbands or headpins are widely used for fixation of the reference frame, and three strategies are generally used for the application of navigation surgery to the mandible. This article reports the application of a novel open position splint integrated with a reference frame and registration markers for mandibular navigation surgery as a fourth strategy. Using this custom-made integrated splint, a marker-based pair-point registration procedure was completed easily and non-invasively. Furthermore, the neurovascular canal tract could be easily identified, and the cyst, as well as the surrounding daughter cysts, could be removed with high accuracy. This strategy has potential for widespread clinical application in mandibular navigation surgery.


Assuntos
Procedimentos Cirúrgicos Ortognáticos , Cirurgia Assistida por Computador , Mandíbula , Contenções
19.
Sci Rep ; 9(1): 14980, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628343

RESUMO

This study reports that high fluence fullerene ion (C60+) irradiation of 1-6 MeV, which was made possible by a new-type of high-flux ion source, elongates metal nanoparticles (NPs) in amorphous SiO2 as efficiently as swift heavy ions (SHIs) of 200 MeV Xe14+, i.e., two orders of the magnitude higher energy ions. Comparing the irradiation effects induced by both the beams, the stopping processes of C60 ions in SiO2 are discussed in this paper. Despite of having almost the same elongation efficiency, the C60+ irradiation induced ~10 times more efficient sputtering due to the clustering enhancement and/or the synergy effect. Ion tracks of ~10.4 nm in diameter and 60-80 nm in length were observed in crystalline SiO2 under 4 MeV C60 irradiation. While the track diameter was comparable to those by SHIs of the same electronic stopping, much shorter track lengths than those predicted by a rigid C60 molecule model indicates that the fragmentation occurred due to nuclear collisions. The elongation of the metal NPs was induced only down to the depth where the tracks were observed but not beyond.

20.
Int J Cosmet Sci ; 41(5): 425-436, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31314913

RESUMO

OBJECTIVE: To assess the impacts of sun exposures on some skin signs on the faces and hands of differently aged Japanese women, according to their distinct behaviours towards vis à vis sun exposure. METHODS: Two comparable cohorts of Japanese women (aged 18-83 years) were created according to their usual behaviour towards sun exposure i.e. non-sun-phobic (N = 495) and sun-phobic (N = 516) and through their regular use(s) of a photo-protective product. Standard photographs (full-face and 45° lateral) allowed to focus on 18 facial signs that were graded by 15 experts, using a referential skin ageing Atlas. From these two cohorts, two sub-cohorts (114 and 122 women) were created with regard to the similar clinical aspects of the dorsal side of their hands (Left vs. Right) that were further graded. Absolute differences in the scores of each sign were used (non-sun-phobic minus sun-phobic), by age-ranges, to better ascertain the impact of sun exposures and photo-protection. RESULTS: Facial signs related to skin wrinkles/texture and pigmentary spots were found significantly more accentuated among non-sun-phobic women and show an early onset (20-30 years). Facial sagging and crow's feet wrinkles appear delayed (30-40 years). The severity of vascular disorders was found to be similar in the two cohorts. The absolute differences in the grading's of almost all signs were unsurprisingly found increased with advancing ages, illustrating the combination of chronological and photo-ageing processes. With regard to hands, differences in skin texture and pigmentary disorders are of a late onset (40-50 years) and were found much increased at older ages. The cutaneous signs of the hands of Japanese women can hardly be taken as reliable markers of their photo-ageing status. CONCLUSION: The present work illustrates, for the first time, some specificities of the impact of sun exposures on the facial skin of Japanese women, pinpointing the fact that some facial signs are of an early onset. Results significantly confirm the importance of both sun avoidance coupled with photo-protective measures.


OBJECTIF: D'évaluer les impacts de l'exposition solaire sur plusieurs signes du visage et des mains de femmes Japonaises d'âge différents, selon leurs différents comportements vis-à-vis de l'exposition solaire. MÉTHODES: Deux cohortes comparables de femmes Japonaises (âgées de 18 à 83 ans) ont été créées selon leur comportement habituel vis à vis de l'exposition solaire, phobique (N = 516) ou non (N = 495) et selon leur utilisation(s) régulière(s) de produits photo-protecteurs. Des photographies standardisées du visage de face et latérales (45°) ont permis de se focaliser sur 18 signes cliniques du visage dont la sévérité a été quantifiée par 15 experts, utilisant un Atlas de référence du vieillissement cutané. De ces deux cohortes, deux sous-cohortes ont été extraites (114 et 122 femmes) par les aspects cliniques similaires de la face dorsale de leurs mains (Gauche vs. Droite) pour être ensuite quantifiées. Les différences absolues de chaque signe (non-phobiques moins phobiques), par tranches d'âges, ont été utilisées pour mieux déterminer l'impact des expositions solaires et des routines de photo-protection. RÉSULTATS: Les signes du visage liés à la texture cutanée/rides et aux taches pigmentaires ont été trouvés significativement aggravés chez les femmes non-phobiques de l'exposition solaire et d'apparition précoce (20-30 ans) tandis que la ptose du visage ou les rides de la patte d'oie apparaissent plus tardivement (30-40 ans). La sévérité des désordres vasculaires du visage a été trouvée similaire dans les deux cohortes. Les différences absolues dans la sévérité de la plupart des signes ont été logiquement trouvées accrues avec l'âge, illustrant la combinaison du vieillissement chronologique et de celui photo-induit. Concernant les mains, les différences dans la texture cutanée et les désordres pigmentaires apparaissent significativement tardives (40-50 ans) et augmentent à des âges plus avancés. Les signes cutanés des mains des femmes Japonaises ne semblent donc pas être des marqueurs fiables du vieillissement photo-induit. CONCLUSION: La présente étude illustre, pour la première fois, quelques spécificités des impacts de l'exposition solaire sur les signes faciaux de femmes Japonaises, pointant le fait que certains sont d'apparition précoce. Les résultats confirment de manière significative l'importance d'éviter les expositions solaires et de recourir à des mesures photo-protectrices.


Assuntos
Face/efeitos da radiação , Mãos/efeitos da radiação , Envelhecimento da Pele , Luz Solar , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Exposição Ambiental , Feminino , Humanos , Japão , Estilo de Vida , Pessoa de Meia-Idade , Adulto Jovem
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