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1.
Phys Rev Lett ; 131(9): 091801, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37721818

RESUMEN

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.

2.
Phys Rev Lett ; 127(8): 081802, 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34477436

RESUMEN

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.

3.
Phys Rev Lett ; 127(6): 061801, 2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34420312

RESUMEN

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.

4.
Br J Dermatol ; 183(1): 146-154, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31605618

RESUMEN

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.


Asunto(s)
Laceraciones , Traumatismos de los Tejidos Blandos , Humanos , Laceraciones/diagnóstico , Reproducibilidad de los Resultados , Piel/lesiones , Encuestas y Cuestionarios
6.
Zhonghua Yi Xue Za Zhi ; 99(45): 3574-3580, 2019 Dec 03.
Artículo en Zh | MEDLINE | ID: mdl-31826574

RESUMEN

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.


Asunto(s)
Neuromielitis Óptica , Alelos , Expresión Génica , Humanos , Leucocitos Mononucleares , Esclerosis Múltiple
7.
Phys Rev Lett ; 121(5): 051301, 2018 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-30118251

RESUMEN

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.

8.
Int J Dent Hyg ; 16(2): e88-e95, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-28984068

RESUMEN

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.


Asunto(s)
Actitud Frente a la Salud , Atención Dental para Niños/estadística & datos numéricos , Caries Dental/prevención & control , Conductas Relacionadas con la Salud , Promoción de la Salud/organización & administración , Servicios de Salud Escolar/organización & administración , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Psicometría , Encuestas y Cuestionarios , Taiwán
9.
Clin Genet ; 92(2): 217-220, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28139839

RESUMEN

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.


Asunto(s)
Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/genética , Pruebas Genéticas , Diagnóstico Prenatal , Adulto , Alelos , Femenino , Síndrome del Cromosoma X Frágil/diagnóstico , Síndrome del Cromosoma X Frágil/patología , Tamización de Portadores Genéticos/métodos , Humanos , Recién Nacido , Masculino , Mutación , Embarazo
11.
Opt Express ; 23(8): 9994-10001, 2015 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-25969040

RESUMEN

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.

12.
Phys Rev Lett ; 115(22): 221803, 2015 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-26650291

RESUMEN

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.

13.
Eur J Neurol ; 22(1): 211-4, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24641183

RESUMEN

BACKGROUND AND PURPOSE: Spastic paraplegia type 5 (SPG5) is an autosomal recessive (AR) hereditary spastic paraplegia (HSP) associated with pure or complicated phenotypes. This study aimed to screen SPG5 in Taiwanese HSP patients. METHODS: Sequencing of the SPG5 gene, CYP7B1, was performed in a cohort of 25 ethnic Han Taiwanese patients with AR or sporadic HSP. Clinical information and magnetic resonance imaging (MRI) were analyzed in confirmed SPG5 patients. RESULTS: One (33%) AR kindred and four (18%) sporadic cases had CYP7B1 mutations. All of the SPG5 cases carried the mutation c.334 C>T (R112X). Haplotype analysis suggested a 'founder effect' in ethnic Hans for this mutation. The phenotype was either pure or complicated by cerebellar ataxia. For the primary HSP phenotype, there were profound dorsal column sensory deficits in all patients. Spine MRI showed thoraco-lumbar cord atrophy in some patients. CONCLUSIONS: Spastic paraplegia type 5 is a common cause of AR and sporadic HSPs that has a higher frequency in Taiwanese than in other ethnic groups. It is associated with a CYP7B1 founder mutation and its phenotype is characterized by pronounced dorsal column sensory loss, with cerebellar ataxia in some patients.


Asunto(s)
Fenotipo , Paraplejía Espástica Hereditaria/genética , Esteroide Hidroxilasas/genética , Adolescente , Adulto , Ataxia Cerebelosa/genética , Familia 7 del Citocromo P450 , Femenino , Efecto Fundador , Haplotipos , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Mutación , Linaje , Paraplejía Espástica Hereditaria/patología , Paraplejía Espástica Hereditaria/fisiopatología , Taiwán , Adulto Joven
14.
Eur J Neurol ; 22(5): 845-52, e59-60, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25690304

RESUMEN

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.


Asunto(s)
Monoaminas Biogénicas/metabolismo , Intoxicación por Monóxido de Carbono/complicaciones , Enfermedad de Parkinson Secundaria , Tomografía de Emisión de Positrones/métodos , Sustancia Blanca/patología , Adulto , Femenino , Radioisótopos de Flúor/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/metabolismo , Enfermedad de Parkinson Secundaria/patología , Enfermedad de Parkinson Secundaria/fisiopatología , Índice de Severidad de la Enfermedad , Tetrabenazina/análogos & derivados , Tetrabenazina/metabolismo
16.
J Sci Med Sport ; 27(1): 16-19, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37923648

RESUMEN

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.


Asunto(s)
Conmoción Encefálica , Natación , Humanos , Conmoción Encefálica/complicaciones
19.
Pharmacopsychiatry ; 46(7): 281-5, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24057776

RESUMEN

INTRODUCTION: The impact of using antidepressant on the occurrence of tardive syndrome is rarely studied. Here we aimed to investigate the prevalence of various types of antidepressant induced tardive syndrome. METHODS: This study was conducted by means of a retrospective survey. Subjects receiving antidepressant(s) for over 6 months, but no other agents that may cause involuntary movements, were consecutively recruited. Tardive syndrome was evaluated in every included subject. Possible confounding medical conditions were carefully ruled out. RESULTS: Of the 158 included subjects, 22 (14.0 %) were found to have at least one tardive syndrome. The prevalence of subtypes of tardive syndromes was: tardive dystonia: 10.8 %, tardive dykinesia: 3.2 %, tardive tremor: 1.3 %, tardive parkinsonism: 1.3 %, tardive tics: 1.3 %, tardive sensory syndrome: 1.3 %, and tardive myoclonus: 0.6 %. Using serotonin-norepinephrine reuptake inhibitors and previous marital status significantly increase the risk of tardive syndrome. DISCUSSION: This study showed that antidepressants may induce various types of tardive syndrome, of which tardive dystonia is the predominant form. Clinicians should be cautious of this infrequent but distressing adverse effect when using antidepressants.


Asunto(s)
Acatisia Inducida por Medicamentos/epidemiología , Antidepresivos/efectos adversos , Discinesia Inducida por Medicamentos/epidemiología , Trastornos del Movimiento/epidemiología , Enfermedad de Parkinson Secundaria/epidemiología , Trastornos de la Sensación/epidemiología , Acatisia Inducida por Medicamentos/complicaciones , Discinesia Inducida por Medicamentos/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Movimiento/complicaciones , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/complicaciones , Prevalencia , Estudios Retrospectivos , Trastornos de la Sensación/inducido químicamente , Trastornos de la Sensación/complicaciones , Síndrome , Taiwán/epidemiología
20.
J Clin Pharm Ther ; 38(2): 81-4, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23216626

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: The deleterious effect of vitamin D deficiency on bone health has long been known. More recent studies suggest a deleterious effect of low vitamin D (hypovitaminosis D) on general health. And specific studies propose an association between hypovitaminosis D and the aetiology and progression of type 2 diabetes (T2DM). Given a commonly assumed lack of toxicity of vitamin D, routine measurement of plasma vitamin D and supplementation is rapidly becoming accepted general practice. COMMENT: Authoritative practice guidelines have raised the level of vitamin D that is to be considered minimal for optimum health. This recommendation was based on a wealth of information and definitive evidence for skeletal benefits of vitamin D, but there was a lack of compelling evidence that hypovitaminosis D is causally related to extra-skeletal health outcomes such as diabetes. Hence, vitamin D supplementation for the purpose of achieving a level consistent with good health is evidence based, but measurement and supplementation for the purpose of preventing or treating T2DM is not. WHAT IS NEW AND CONCLUSION: Although the maintenance of adequate vitamin D levels is desirable for all patients, we conclude that routine measurement of vitamin D level in every patient or initiating high-dose supplementation for the purpose of preventing or treating T2DM is not evidence based.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Deficiencia de Vitamina D/metabolismo , Vitamina D/administración & dosificación , Vitamina D/sangre , Diabetes Mellitus Tipo 2/sangre , Suplementos Dietéticos , Humanos , Guías de Práctica Clínica como Asunto , Vitamina D/efectos adversos , Deficiencia de Vitamina D/sangre
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