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1.
J Sci Med Sport ; 27(1): 16-19, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37923648

RESUMO

Para swimmers with limb deficiency are faced with the particular situation that they must use their head to finish each competition by a hit to the wall. Repetitive head impacts may impair behavioral and brain functions. We therefore investigated neurobehavioral functions of a Para swimmer with dysmelia before and after repetitive head impacts (T1) and without (T2). Average head impact at T1 constituted 13.6 g with a mean impact force of 6689.9 N. Behavioral and brain functions decreased from pre to post at T1 but not at T2. Para swimmers with limb deficiency are therefore affected from the same consequences onto brain health that are observed after repeated sport-related concussions.


Assuntos
Concussão Encefálica , Natação , Humanos , Concussão Encefálica/complicações
2.
Phys Rev Lett ; 131(9): 091801, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721818

RESUMO

We measured the nuclear-recoil ionization yield in silicon with a cryogenic phonon-sensitive gram-scale detector. Neutrons from a monoenergetic beam scatter off of the silicon nuclei at angles corresponding to energy depositions from 4 keV down to 100 eV, the lowest energy probed so far. The results show no sign of an ionization production threshold above 100 eV. These results call for further investigation of the ionization yield theory and a comprehensive determination of the detector response function at energies below the keV scale.

4.
Phys Rev Lett ; 127(8): 081802, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34477436

RESUMO

The Cryogenic Dark Matter Search low ionization threshold experiment (CDMSlite) achieved efficient detection of very small recoil energies in its germanium target, resulting in sensitivity to lightly ionizing particles (LIPs) in a previously unexplored region of charge, mass, and velocity parameter space. We report first direct-detection limits calculated using the optimum interval method on the vertical intensity of cosmogenically produced LIPs with an electric charge smaller than e/(3×10^{5}), as well as the strongest limits for charge ≤e/160, with a minimum vertical intensity of 1.36×10^{-7} cm^{-2} s^{-1} sr^{-1} at charge e/160. These results apply over a wide range of LIP masses (5 MeV/c^{2} to 100 TeV/c^{2}) and cover a wide range of ßγ values (0.1-10^{6}), thus excluding nonrelativistic LIPs with ßγ as small as 0.1 for the first time.

5.
Phys Rev Lett ; 127(6): 061801, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34420312

RESUMO

We present limits on spin-independent dark matter-nucleon interactions using a 10.6 g Si athermal phonon detector with a baseline energy resolution of σ_{E}=3.86±0.04(stat)_{-0.00}^{+0.19}(syst) eV. This exclusion analysis sets the most stringent dark matter-nucleon scattering cross-section limits achieved by a cryogenic detector for dark matter particle masses from 93 to 140 MeV/c^{2}, with a raw exposure of 9.9 g d acquired at an above-ground facility. This work illustrates the scientific potential of detectors with athermal phonon sensors with eV-scale energy resolution for future dark matter searches.

6.
J Dent Res ; 100(10): 1178-1185, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34235985

RESUMO

In compromised bone conditions such as osteoporosis, developments of the implant surface are necessary to secure the stability of implants. This study investigated the effect of the surface porous titanium structure (PS) on the osseointegration of implants in osteoporotic bone. Bilateral ovariectomy (OVX) was performed in 4 female beagle dogs to induce osteoporosis for 32 wk. Success of induction was based on the evaluation of bone mineral density by Hounsfield units (HU) in computed tomography images. Posterior teeth in both mandibles were extracted 1 wk after OVX, and a total of 30 implants (15 implants in each group) were placed after 32 wk of osteoporosis induction. The control group implant underwent resorbable blast media (RBM) surface treatment, whereas the test group underwent RBM surface treatment in the coronal two-thirds and a PS added to the apical 3-mm portion. HU values in the mandibular trabecular bone, lumbar, and femoral head significantly decreased 32 wk after OVX, confirming osteoporotic condition after induction. Resonance frequency analysis and removal torque test showed comparable values between the 2 groups at 4 wk after implant placement. The surface topography of the implant after removal showed hard tissue integration at the PS in the test group. Bone-to-implant contact length was greater in the apical portion of the test group, although statistical significance was not found between the groups. Interthread bone area in the apical portion of the test group showed a significant increase compared to the control group (control: 0.059 ± 0.041 mm2, test: 0.121 ± 0.060 mm2, P = 0.028) with the histological feature of bone ingrowth at the PS. The findings of the study demonstrated that the surface PS could improve osteoconductivity in the osteoporotic trabecular bone by bone ingrowth at the pore space, thereby enhancing the osseointegration and stability of the implants.


Assuntos
Implantes Dentários , Osteoporose , Animais , Densidade Óssea , Cães , Feminino , Humanos , Osseointegração , Osteoporose/diagnóstico por imagem , Ovariectomia , Porosidade , Propriedades de Superfície , Titânio
7.
Nat Commun ; 12(1): 2895, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001874

RESUMO

Plasma wakefield accelerators are capable of sustaining gigavolt-per-centimeter accelerating fields, surpassing the electric breakdown threshold in state-of-the-art accelerator modules by 3-4 orders of magnitude. Beam-driven wakefields offer particularly attractive conditions for the generation and acceleration of high-quality beams. However, this scheme relies on kilometer-scale accelerators. Here, we report on the demonstration of a millimeter-scale plasma accelerator powered by laser-accelerated electron beams. We showcase the acceleration of electron beams to 128 MeV, consistent with simulations exhibiting accelerating gradients exceeding 100 GV m-1. This miniaturized accelerator is further explored by employing a controlled pair of drive and witness electron bunches, where a fraction of the driver energy is transferred to the accelerated witness through the plasma. Such a hybrid approach allows fundamental studies of beam-driven plasma accelerator concepts at widely accessible high-power laser facilities. It is anticipated to provide compact sources of energetic high-brightness electron beams for quality-demanding applications such as free-electron lasers.

8.
Br J Dermatol ; 183(1): 146-154, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31605618

RESUMO

BACKGROUND: Skin tears are acute wounds that are frequently misdiagnosed and under-reported. A standardized and globally adopted skin tear classification system with supporting evidence for diagnostic validity and reliability is required to allow assessment and reporting in a consistent way. OBJECTIVES: To measure the validity and reliability of the International Skin Tear Advisory Panel (ISTAP) Classification System internationally. METHODS: A multicountry study was set up to validate the content of the ISTAP Classification System through expert consultation in a two-round Delphi procedure involving 17 experts from 11 countries. An online survey including 24 skin tear photographs was conducted in a convenience sample of 1601 healthcare professionals from 44 countries to measure diagnostic accuracy, agreement, inter-rater reliability and intrarater reliability of the instrument. RESULTS: A definition for the concept of a 'skin flap' in the area of skin tears was developed and added to the initial ISTAP Classification System consisting of three skin tear types. The overall agreement with the reference standard was 0·79 [95% confidence interval (CI) 0·79-0·80] and sensitivity ranged from 0·74 (95% CI 0·73-0·75) to 0·88 (95% CI 0·87-0·88). The inter-rater reliability was 0·57 (95% CI 0·57-0·57). The Cohen's Kappa measuring intrarater reliability was 0·74 (95% CI 0·73-0·75). CONCLUSIONS: The ISTAP Classification System is supported by evidence for validity and reliability. The ISTAP Classification System should be used for systematic assessment and reporting of skin tears in clinical practice and research globally. What's already known about this topic? Skin tears are common acute wounds that are misdiagnosed and under-reported too often. A skin tear classification system is needed to standardize documentation and description for clinical practice, audit and research. What does this study add? The International Skin Tear Advisory Panel Classification System was psychometrically tested in 1601 healthcare professionals from 44 countries. Diagnostic accuracy was high when differentiating between type 1, 2 and 3 skin tears using a set of validated photographs.


Assuntos
Lacerações , Lesões dos Tecidos Moles , Humanos , Lacerações/diagnóstico , Reprodutibilidade dos Testes , Pele/lesões , Inquéritos e Questionários
9.
Zhonghua Yi Xue Za Zhi ; 99(45): 3574-3580, 2019 Dec 03.
Artigo em Chinês | MEDLINE | ID: mdl-31826574

RESUMO

Objective: To investigate the effect of HLA-DP gene expression on the susceptibility and disease status of neuromyelitis optica spectrum disorders (NMOSD). Methods: A total of 86 NMOSD patients (52 in acute phase and 34 in remission phase), 52 multiple sclerosis (MS) patients (20 in acute phase and 32 in remission phase) diagnosed in Department of Neurology, the Third Affiliated Hospital of Sun Yat-sen University and 29 healthy controls were enrolled prospectively. Genotyping of HLA-DP was performed. The expression levels of HLA-DP molecules in peripheral blood B cells and monocytes were measured by flow cytometry. The transcription levels of HLA-DPB1 mRNA in peripheral blood mononuclear cells (PBMC) were measured by real time-PCR. The results were compared among different groups Results: There was no statistically significant difference of the distributions of HLA-DPB1*0501/HLA-DPB1*0501, HLA-DPB1*0501/X and X/X genotypes and the frequencies of allele of HLA-DPB1*0501 among NMOSD, MS patients and healthy controls (P=0.96 and 0.71, respectively). The expression levels of HLA-DP on the surface of B cells in NMOSD patients, especially in remission phase patients, were significantly higher than those in healthy controls(212±328 and 374±394 vs 55±57, P=0.049 and 0.002, respectively). The expression levels of HLA-DP on the surface of monocytes in NMOSD patients in acute phase were significantly higher than those in healthy controls(158±175 vs 65±90, P=0.025). The transcription levels of PMBC HLA-DPB1 mRNA in acute phase and remission phase of NMOSD patients were significantly higher than those in healthy controls (3.0±1.4 and 2.9±1.3 vs 1.5±1.4, P=0.000 and 0.003, respectively). The expression levels of HLA-DP molecules on the surface of peripheral blood B cells and monocytes and the transcription levels of PMBC HLA-DPB1 mRNA in MS patients at the acute and remission stages were not significantly different from those in healthy controls. The expression levels of HLA-DP molecules on the surface of B cells in patients with HLA-DPB1*0501/HLA-DPB1*0501, HLA-DPB1*0501/X and X/X genotypes were statistically different (P=0.017). Conclusion: HLA-DP gene transcription and molecular expression levels in antigen presenting cells may affect the susceptibility and disease status of NMOSD patients, while HLA-DPB1*0501 allele may affect the transcription and molecular expression levels of HLA-DP gene in antigen presenting cells.


Assuntos
Neuromielite Óptica , Alelos , Expressão Gênica , Humanos , Leucócitos Mononucleares , Esclerose Múltipla
13.
Phys Rev Lett ; 121(5): 051301, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-30118251

RESUMO

We present the first limits on inelastic electron-scattering dark matter and dark photon absorption using a prototype SuperCDMS detector having a charge resolution of 0.1 electron-hole pairs (CDMS HVeV, a 0.93 g CDMS high-voltage device). These electron-recoil limits significantly improve experimental constraints on dark matter particles with masses as low as 1 MeV/c^{2}. We demonstrate a sensitivity to dark photons competitive with other leading approaches but using substantially less exposure (0.49 g d). These results demonstrate the scientific potential of phonon-mediated semiconductor detectors that are sensitive to single electronic excitations.

15.
Materials (Basel) ; 11(1)2018 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-29316687

RESUMO

Hard coatings have been adopted in cutting and forming applications for nearly two decades. The major purpose of using hard coatings is to reduce the friction coefficient between contact surfaces, to increase strength, toughness and anti-wear performance of working tools and molds, and then to obtain a smooth work surface and an increase in service life of tools and molds. In this report, we deposited a composite CrTiSiN hard coating, and a traditional single-layered TiAlN coating as a reference. Then, the coatings were comparatively studied by a series of tests. A field emission SEM was used to characterize the microstructure. Hardness was measured using a nano-indentation tester. Adhesion of coatings was evaluated using a Rockwell C hardness indentation tester. A pin-on-disk wear tester with WC balls as sliding counterparts was used to determine the wear properties. A self-designed compression and friction tester, by combining a Universal Testing Machine and a wear tester, was used to evaluate the contact behavior of composite CrTiSiN coated dies in compressing of Mg alloy sheets under high pressure. The results indicated that the hardness of composite CrTiSiN coating was lower than that of the TiAlN coating. However, the CrTiSiN coating showed better anti-wear performance. The CrTiSiN coated dies achieved smooth surfaces on the Mg alloy sheet in the compressing test and lower friction coefficient in the friction test, as compared with the TiAlN coating.

16.
Int J Dent Hyg ; 16(2): e88-e95, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28984068

RESUMO

OBJECTIVES: This study aimed to develop and validate a new instrument based on the health belief model and to use the instrument to investigate the determinants of regular dental attendance among primary schoolchildren. METHODS: A cross-sectional study was conducted using a newly developed measurement scale based on the HBM, 4 health-promoting schools participated in the study and 958 students studying in grades 4-6 completed the questionnaire. The psychometric properties of the instrument were analysed, and a path analysis model was used to identify the determinants of regular dental attendance. RESULTS: The instrument had good internal consistency (Cronbach's α = 0.826-0.925) and a factor structure identical to HBM. Overall, the schoolchildren's health beliefs on caries treatment were positive. The determinants of regular dental visit were school location (ß = -0.13), mother's education level (ß = 0.15), susceptibility (ß = -0.18) and barriers (ß = -0.11). CONCLUSION: This study provided evidence that HBM is applicable to children's dental visiting behaviour and their health beliefs towards adherence to caries treatment. Although children had a positive attitude towards dental visits, environmental obstacles would interfere with dental visits. The newly developed instrument could be used to identify high-risk children and help design oral health interventions for these children. Moreover, policy makers should increase the accessibility of dental resources to enhance the utilization of dental care among schoolchildren.


Assuntos
Atitude Frente a Saúde , Assistência Odontológica para Crianças/estatística & dados numéricos , Cárie Dentária/prevenção & controle , Comportamentos Relacionados com a Saúde , Promoção da Saúde/organização & administração , Serviços de Saúde Escolar/organização & administração , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Psicometria , Inquéritos e Questionários , Taiwan
17.
Clin Genet ; 92(2): 217-220, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28139839

RESUMO

Here, we review the results of Southern blotting analyses of the FMR1 gene performed in our reference laboratory in Taiwan over a 15-year period. In total, 725 high-risk women with a family history of fragile X syndrome (FXS) or idiopathic intellectual disability, 3911 low-risk pregnant women without such family history, and prenatal diagnosis data for 32 foetuses from 24 carrier mothers were included. Only 2 carriers were in the low-risk group, which indicated a prevalence of 1 of 1955 women (95% confidence interval: 1/7156-1/539). A total of 100 carriers were found to be in the high-risk group, thus revealing a significantly higher frequency than the low-risk group (100/725 vs 2/3911, P<0.0001). Eight of the 14 foetuses that inherited the maternal mutant allele were verified to have a full mutation, with the smallest maternal pre-mutation allele carrying 56 CGG repeats. The overall findings confirmed that the carrier prevalence among low-risk women in Taiwan is significantly lower than that reported in western countries. Therefore, the most important step for preventing FXS in Taiwan would be to focus on high-risk women by promoting general awareness of this disease and spreading knowledge regarding the benefits of carrier screening and prenatal testing.


Assuntos
Proteína do X Frágil da Deficiência Intelectual/genética , Síndrome do Cromossomo X Frágil/genética , Testes Genéticos , Diagnóstico Pré-Natal , Adulto , Alelos , Feminino , Síndrome do Cromossomo X Frágil/diagnóstico , Síndrome do Cromossomo X Frágil/patologia , Triagem de Portadores Genéticos/métodos , Humanos , Recém-Nascido , Masculino , Mutação , Gravidez
18.
Phys Rev Lett ; 115(22): 221803, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26650291

RESUMO

We report the first observation of the decays B^{0}→pΛ[over ¯]D^{(*)-}. The data sample of 711 fb^{-1} used in this analysis corresponds to 772×10^{6} BB[over ¯] pairs, collected at the ϒ(4S) resonance by the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We observe 19.8σ and 10.8σ excesses of events for the two decay modes and measure the branching fractions of B^{0}→pΛ[over ¯]D^{-} and B^{0}→pΛ[over ¯]D^{*-} to be (25.1±2.6±3.5)×10^{-6} and (33.6±6.3±4.4)×10^{-6}, respectively, where the first uncertainties are statistical and the second are systematic. These results are not compatible with the predictions based on the generalized factorization approach. In addition, a threshold enhancement in the dibaryon (pΛ[over ¯]) system is observed, consistent with that observed in similar B decays.

19.
Opt Express ; 23(8): 9994-10001, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25969040

RESUMO

We report a high-efficiency hard-X-ray resonator with inclined-incidence geometry. A beam incident at 36.87° with respect to [3 1 0] excites Bragg back diffraction along (12 4 0) at 14.4388 keV for resonance in a Si-based resonator to produce intense resonance fringes. The experimental results showed the visibility enhanced by nearly 30 times compared with normal incidence. Also numerical calculations of the inclined-incidence resonator demonstrate ultrahigh efficiency and extremely narrow resolving power (sub-meV) with low background. This geometry surpasses the intrinsic limits of normal-incidence crystal-based resonators and enables ultrahigh-resolution X-ray optics for X-ray diffraction, spectroscopy, and imaging applications.

20.
Eur J Neurol ; 22(5): 845-52, e59-60, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25690304

RESUMO

BACKGROUND AND PURPOSE: Although parkinsonism after carbon monoxide (CO) intoxication is well known, neurotransmitter deficient networks that are responsible for the severity of parkinsonism have rarely been systemically evaluated. METHODS: Eighteen patients with CO-related parkinsonism and nine age- and sex-matched controls were enrolled for detailed neurological examinations, three-dimensional T1-weighted images, diffusion tensor imaging and (18)F-9-fluoropropyl-(+)-dihydrotetrabenzazine ((18)F-FP-(+)-DTBZ) positron emission tomography (PET). The structural analysis included voxel-based morphometry to assess grey matter atrophy and tract-based spatial statistics related to white matter involvement. For presynaptic monoaminergic assessment, volume of interest analysis in six subcortical regions and non-parametric voxel-wise comparison were performed on PET images with estimation of registration parameters from magnetic resonance images. All the imaging modalities were compared between the patients and controls. For the patients, a regression model for correlation with cognitive behaviour and Unified Parkinson's Disease Rating Scale (UPDRS) score was used. RESULTS: In the patients, monoaminergic deficit networks were found in the caudate, anterior putamen, anterior insular, thalamus and anterior cingulate cortex. The UPDRS revealed significant correlations with the prefrontal white matter fractional anisotropy values and with the (18)F-FP-(+)-DTBZ uptake values in the caudate nucleus, insular, medial prefrontal and dorsomedial thalamus. The neuropsychiatric inventory score correlated with the (18)F-FP-(+)-DTBZ uptake values in the anterior cingulate cortex and dorsolateral prefrontal cortex. CONCLUSIONS: Our study demonstrated monoaminergic deficits and white matter damage networks in CO-related parkinsonism that determined the severity of parkinsonism or behaviour changes. As the substantia nigra was spared, the monoaminergic topography of involvement suggests a different pathophysiology in CO-related parkinsonism.


Assuntos
Monoaminas Biogênicas/metabolismo , Intoxicação por Monóxido de Carbono/complicações , Doença de Parkinson Secundária , Tomografia por Emissão de Pósitrons/métodos , Substância Branca/patologia , Adulto , Feminino , Radioisótopos de Flúor/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/metabolismo , Doença de Parkinson Secundária/patologia , Doença de Parkinson Secundária/fisiopatologia , Índice de Gravidade de Doença , Tetrabenazina/análogos & derivados , Tetrabenazina/metabolismo
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