Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Front Public Health ; 12: 1419886, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39360263

RESUMEN

Introduction: We described how COVID-19 fatality and symptoms varied by dominant variant and vaccination in the US. Methods: Using the Restricted Access Dataset from the US CDC (1/1/2020-10/20/2022), we conducted a cross-sectional study assessing differences in COVID-19 deaths, severity indicators (hospitalization, ICU, pneumonia, abnormal X-ray, acute respiratory distress syndrome, mechanical ventilation) and 12 mild symptoms by dominant variant/vaccination periods using logistic regression after controlling for confounders. Results: We found the highest fatality during the dominant periods of Wild (4.6%) and Delta (3.4%). Most severe symptoms appeared when Delta was dominant (Rate range: 2.0-9.4%). Omicron was associated with higher mild symptoms than other variants. Vaccination showed consistent protection against death and severe symptoms for most variants (Risk Ratio range: 0.41-0.93). Boosters, especially the second, provided additional protection, reducing severe symptoms by over 50%. Discussion: This dataset may serve as a useful tool to monitor temporospatial changes of fatality and symptom for case management and surveillance.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , COVID-19/mortalidad , Estados Unidos/epidemiología , Estudios Transversales , Persona de Mediana Edad , Masculino , Femenino , Eficacia de las Vacunas/estadística & datos numéricos , Adulto , Anciano , Índice de Severidad de la Enfermedad
2.
Theranostics ; 14(13): 5184-5199, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39267774

RESUMEN

Rationale: Chemoresistance is a key factor contributing to the failure of anti-breast cancer chemotherapy. Although abnormal glycosylation is closely correlated with breast cancer progression, the function of glycoconjugates in chemoresistance remains poorly understood. Methods: Levels and regulatory roles of bisecting N-acetylglucosamine (GlcNAc) in chemoresistant breast cancer cells were determined in vitro and in vivo. Glycoproteomics guided identification of site-specific bisecting GlcNAc on P-glycoprotein (P-gp). Co-immunoprecipitation coupled mass spectrometry (Co-IP-MS) and proximity labelling MS identified the interactome of P-gp, and the biological function of site-specific bisecting GlcNAc was investigated by site/truncation mutation and structural simulations. Results: Bisecting GlcNAc levels were reduced in chemoresistant breast cancer cells, accompanied by an enhanced expression of P-gp. Enhanced bisecting GlcNAc effectively reversed chemoresistance. Mechanical study revealed that bisecting GlcNAc impaired the association between Ezrin and P-gp, leading to a decreased expression of membrane P-gp. Bisecting GlcNAc suppressed VPS4A-mediated P-gp recruitment into microvesicles, and chemoresistance transmission. Structural dynamics analysis suggested that bisecting GlcNAc at Asn494 introduced structural constraints that rigidified the conformation and suppressed the activity of P-gp. Conclusion: Our findings highlight the crucial role of bisecting GlcNAc in chemoresistance and suggest the possibility of reversing chemoresistance by modulating the specific glycosylation in breast cancer therapy.


Asunto(s)
Acetilglucosamina , Neoplasias de la Mama , Resistencia a Antineoplásicos , Humanos , Resistencia a Antineoplásicos/efectos de los fármacos , Acetilglucosamina/metabolismo , Animales , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/genética , Femenino , Línea Celular Tumoral , Glicosilación/efectos de los fármacos , Ratones , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Ratones Desnudos , Proteínas del Citoesqueleto
3.
J Psychiatr Res ; 174: 297-303, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38678687

RESUMEN

BACKGROUND: Biological rhythms denote the cyclical patterns of life activities anchored to a 24-hour cycle. Research shows that depression exhibits disturbances in biological rhythms. Yet, the relationship between these biological rhythms and concomitant anxiety symptoms is insufficiently investigated in structured clinical assessments. METHODS: This multicenter study, carried out in four Chinese hospitals, comprehensively examined the relationship between anxiety and disruptions in biological rhythms among patients with depression. The study encompassed 218 patients diagnosed with depression and 205 matched healthy controls. The Chinese version of the Biological Rhythms Interview of Assessment in Neuropsychiatry was utilized to evaluate the participants' biological rhythms, focusing on four dimensions: sleep, activity, social, and diet. RESULTS: In patients with depression, there is a significant positive correlation between the severity of anxiety symptoms and the disturbances in biological rhythms. The severity of anxiety and depression, along with the quality of life, are independently associated with disruptions in biological rhythms. The mediation model reveals that anxiety symptoms mediate the relationship between depressive symptoms and biological rhythms. CONCLUSION: This research highlights the role of anxiety within the spectrum of depressive disorders and the associated disturbances in biological rhythms. Our findings shed light on potential pathways towards more targeted preventive strategies and therapeutic interventions for individuals battling depression and anxiety.


Asunto(s)
Ansiedad , Humanos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Ansiedad/fisiopatología , Depresión/fisiopatología , Ritmo Circadiano/fisiología , Trastorno Depresivo/fisiopatología , Adulto Joven , Trastornos Cronobiológicos/fisiopatología
4.
Neuroreport ; 35(9): 577-583, 2024 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-38687887

RESUMEN

Pyroptosis, a form of programmed cell death, drives inflammation in the context of cerebral ischemia/reperfusion. The molecular mechanism of pyroptosis underlying ischemia/reperfusion, however, is not fully understood. The transient middle cerebral artery occlusion was applied to wild-type and caspase-1 knockout mice. 2,3,5-Triphenyltetrazolium chloride-staining and immunohistochemistry were used to identify the ischemic region, and western blot and immunofluorescence for the examination of neuronal pyroptosis. The expression of inflammatory factors and the behavioral function assessments were further conducted to examine the effects of caspase-1 knockout on protection against ischemia/reperfusion injury. Ischemia/reperfusion injury increased pyroptosis-related signals represented by the overexpression of pyroptosis-related proteins including caspase-1 and gasdermin D (GSDMD). Meanwhile, the number of GSDMD positive neurons increased in penumbra by immunofluorescence staining. Compared with wild-type mice, those with caspase-1 knockout exhibited decreased levels of pyroptosis-related proteins following ischemia/reperfusion. Furthermore, ischemia/reperfusion attack-induced brain infarction, cerebral edema, inflammatory factors, and neurological outcomes were partially improved in caspase-1 knockout mice. The data indicate that pyroptosis participates in ischemia/reperfusion induced-damage, and the caspase-1 might be involved, it provides some new insights into the molecular mechanism of ischemia.


Asunto(s)
Caspasa 1 , Infarto de la Arteria Cerebral Media , Piroptosis , Daño por Reperfusión , Animales , Masculino , Ratones , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Caspasa 1/metabolismo , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/metabolismo , Neuronas/patología , Piroptosis/fisiología , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología
5.
Small ; 20(13): e2306767, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37990397

RESUMEN

Structured liquids in miscible fluids, due to ineffective resistance to withstand particle self-diffusion, differ from that in immiscible liquids because of interfacial interactions. Here, a kind of structured liquid, jammed by thiol-terminated polystyrene-modified gold nanorods (GNRs) within tetrahydrofuran and toluene (TOL), is developed by introducing electrostatic repulsion to counterbalance the self-diffusion of GNRs. First-principle calculations reveal charge transfer between the GNRs and TOL, resulting in the electrostatic repulsion. The structured liquids can be regarded as mimic "loading vehicles" to controllably carry and transport matter under electric or magnetic fields, where release rate can be adjusted by changing the concentration of the soluble matter for slow release and using the photothermal effect of the assembled GNRs for fast release. This work has developed a new assembly mechanism to form structured liquids, allowing the construction of a flexible and robust droplet platform with possible applications in microreactors, biomimetic permeable membranes, and functional liquid robots.

6.
Opt Express ; 31(15): 24623-24632, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37475284

RESUMEN

An all-fiber fiber coupler was demonstrated for pumping orbital angular momentum (OAM) modes amplification, which was fabricated by side-polishing and bonding a ring-core erbium-doped fiber (RC-EDF) and a pre-tapered side-polished single-mode fiber (SMF). With the selected phase-matching condition at 976 nm, the pumping laser was coupled into the RC-EDF from the SMF with optimized high efficiency, whereas the 1st to 3rd-order OAM mode signals were transmitted with the low insertion loss in the RC-EDF over a broadband wavelength range from 1530 to 1565 nm. This all-fiber wavelength division multiplexing coupler was optimized by the polished length and depth of the two coupled fibers. The insertion loss for the OAM signal modes was obtained lower than 0.58 dB with the pump power coupling ratio of above 90%. The proposed side-polished pumping coupler technique can ensure high-order OAM modes amplification, paving the way for the all-fiber optical amplifier in high-capacity modal-division multiplexing fiber communication systems.

8.
Medicine (Baltimore) ; 99(33): e20805, 2020 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-32871971

RESUMEN

Patients with acute coronary syndrome (ACS) have an increased serum level of calprotectin. The purpose of present study was to analyze the prognostic significance of serum calprotectin levels in elderly diabetic patients underwent percutaneous coronary intervention (PCI) due to ACS.A total of 273 consecutive elderly diabetic patients underwent PCI for primary ACS were enrolled. Serum calprotectin levels were measured before PCI, and baseline clinical characteristics of all patients were collected. All patients were followed up at regular interval for major adverse cardiovascular events (MACEs) during 1 year after PCI. MACEs include cardiovascular death, nonfatal myocardial infarction, and target vessel revascularization (TVR). The predicting value of serum calprotectin for MACEs was analyzed by using univariate and multivariate analysis and receiver-operating characteristic curve (ROC).At the endpoint of this study, 47 patients of all 273 patients had MACEs. According to optimal cutoff value of calprotectin for predicting MACEs by ROC analysis, all patients were stratified into a high calprotectin group and a low calprotectin group. The incidence rate of MACEs and TVR in high calprotectin group was prominently higher than that in low calprotectin group (21.9% vs 11.5%, P = .02). In multivariable COX regression analysis adjusting for potential confounders, serum calprotectin level remains as an independent risk predictor of MACE (hazard ratio, 1.56; 95% confidence interval [CI]: 1.08-4.62; P = .01).In diabetic patients with a comorbidity of ACS, a high serum level of calprotectin is associated to a higher MACE rate after PCI.


Asunto(s)
Síndrome Coronario Agudo/sangre , Síndrome Coronario Agudo/cirugía , Complicaciones de la Diabetes/sangre , Complejo de Antígeno L1 de Leucocito/sangre , Intervención Coronaria Percutánea , Síndrome Coronario Agudo/epidemiología , Anciano , Biomarcadores/sangre , Estudios de Cohortes , Comorbilidad , Complicaciones de la Diabetes/epidemiología , Complicaciones de la Diabetes/cirugía , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/sangre , Pronóstico
9.
Inorg Chem ; 59(1): 875-879, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31868353

RESUMEN

A novel metal-organic ligand (MOL 2) has been prepared by linking two V-shaped bis-terpyridines with one X-shaped tetrakis-terpyridine through the stable connectivity. The complexation between MOL 2, X-shaped tetrakis-terpyridine, and Zn2+ gave rise to a supramolecular C6-symmetrical six-pointed star quantitatively. In addition, a mixture of MOL 2, K-shaped tetrakis-terpyridine, and Zn2+ afforded a C2-symmetrical four-pointed star. These metallo-supramolecular architectures were adequately characterized by NMR, ESI-MS, TWIM-MS, and TEM analyses.

10.
Artículo en Inglés | MEDLINE | ID: mdl-31362347

RESUMEN

The Chinese government projected 30% of total consumed potatoes as a staple food (PSF) by 2020. We comprehensively assessed the potential impacts of PSF on rice and flour consumption, rice and wheat planting, energy and nutrient supply, irrigation-water, chemical nitrogen (N), phosphorus pentoxide (P2O5) and potassium oxide (K2O) fertilizer inputs and total greenhouse gases (GHG) emission for potatoes, rice and wheat, by assuming different proportions of potato substitutes for rice and flour. The results showed that per capita, 2.9 ± 0.3 and 4.7 ± 0.5 kg more potatoes per year would enter the Chinese staple-food diet, under the government's target. PSF consumed are expected to reach 5.2 ± 0.7 Tg yr-1, equivalent to substituting potatoes for 4.2 ± 0.8-8.5 ± 0.8 Tg yr-1 wheat and 5.1 ± 0.9-10.1 ± 1.8 Tg yr-1 rice under different scenarios. While this substitution can increase the nutrient supply index by 63% towards nutrient reference values, it may induce no significant effect on staple-food energy supply with lower chemical fertilizer (except for K2O) and irrigation-water inputs and GHG emissions in different substitution scenarios than the business as usual scenario. The reduction in rice and wheat demands lead to wheat in the North China Plain and early rice decrease by 6.1-11.4% and 12.1-24.1%, respectively. The total GHG reduction is equal to 1.1-9.0% of CO2 equivalent associated with CH4 and N2O emitted from the Chinese agroecosystem in 2005. The saved irrigation water for three crops compared to 2012 reaches the total water use of 17.9 ± 4.9-21.8 ± 5.9 million people in 2015. More N fertilizer, irrigation-water, and GHG can be reduced, if the PSF ratio is increased to 50% together with potato yield improves to the optimal level. Our results implied that the PSF policy is worth doing not only because of the healthier diets, but also to mitigate resource inputs and GHG emissions and it also supports agricultural structure adjustments in the areas of irrigated wheat on the North China Plain and early rice across China, designed to increase the adaptability to climate change.


Asunto(s)
Productos Agrícolas , Abastecimiento de Alimentos , Política Nutricional , Solanum tuberosum , Agricultura/métodos , China , Fertilizantes/análisis , Gases de Efecto Invernadero , Nitrógeno/química , Óxido Nitroso/análisis , Oryza , Triticum , Agua
11.
Inorg Chem ; 58(12): 7662-7666, 2019 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-31150212

RESUMEN

A shape-persistent metallosupramolecular multirhomboid that inlays a hexarhomboid polygon in a three-lobed flat structure was prepared by means of coordination-driven self-assembly. The key ligands were synthesized by a "reaction on complex" strategy that becomes accessible to troublesome metalloorganic ligand L3. The formation here consists of four different starting components and two metal ions. Complementarity of the shape and size drives molecular puzzling and results in the multicomponent, quantitative self-assembled construct.

12.
Water Res X ; 22019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30882067

RESUMEN

Urban water and wastewater utilities are striving to improve their environmental and economic performances due to multiple challenges such as increasingly stringent quality criterion, aging infrastructure, constraining financial burden, growing urban population, climate challenges and dwindling resources. Growing needs of holistic assessments of urban water systems are required to identify systems-level cross-domain solutions. This study evaluated the life cycle environmental and economic impacts of urban water and wastewater systems with two utilities in Greater Cincinnati region as a case study. The scope of this study includes the entire urban water and wastewater systems starting from raw water acquisition for drinking water to wastewater treatment and discharge. The detailed process-based life cycle models were developed based on the datasets provided by local water and wastewater utilities. The life cycle assessment indicated that the operation and maintenance of drinking water distribution was a dominating contributor for energy consumption (43%) and global warming potential (41%). Wastewater discharge from the wastewater treatment plant contributed to more than 80% of the total eutrophication potential. The cost analysis determined that labor and maintenance cost (19%) for wastewater collection, and electricity cost (13%) for drinking water distribution were major contributors. Electricity purchased by the utility was the driver for the majority of impact categories assessed with the exception of eutrophication, blue water use, and metal depletion. Infrastructure requirements had a negligible influence on impact results, contributing less than 3% to most categories, with the exception of metal depletion where it led to 68% of total burdens. Sensitivity analysis showed that the life cycle environmental results were more sensitive to the choice of the electricity mixes and electricity consumption than the rest of input parameters such as chemical dosages, and infrastructure life time. This is one of the first comprehensive studies of the whole urban water system using real case data. It elucidates a bigger picture of energy, resource and cost distributions in a typical urban centralized water system. Inherent to a modern city as large population centers, a significant expenditure has to be invested to provide water services function (moving water, treating water/wastewater) in order to avoid human and environmental health problems. This study provides insights for optimization potentials of overall treatment efficiency and can serve as a benchmark for communities considering adoption of alternative water systems.

13.
Bioresour Technol ; 254: 56-66, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29413939

RESUMEN

This study calculated the energy and greenhouse gas life cycle and cost profiles of transitional aerobic membrane bioreactors (AeMBR) and anaerobic membrane bioreactors (AnMBR). Membrane bioreactors (MBR) represent a promising technology for decentralized wastewater treatment and can produce recycled water to displace potable water. Energy recovery is possible with methane generated from AnMBRs. Scenarios for these technologies were investigated for different scale systems serving various population densities under a number of climate conditions with multiple methane recovery options. When incorporating the displacement of drinking water, AeMBRs started to realize net energy benefits at the 1 million gallons per day (MGD) scale and mesophilic AnMBRs at the 5 MGD scale. For all scales, the psychrophilic AnMBR resulted in net energy benefits. This study provides insights into key performance characteristics needed before an informed decision can be made for a community to transition towards the adoption of MBR technologies.


Asunto(s)
Reactores Biológicos , Gases de Efecto Invernadero , Metano , Anaerobiosis , Clima , Membranas Artificiales , Densidad de Población , Eliminación de Residuos Líquidos , Aguas Residuales , Purificación del Agua
14.
Chem Commun (Camb) ; 53(50): 6732-6735, 2017 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-28589204

RESUMEN

Self-assembly of a metallo-organic ligand, composed of an inner uncomplexed 120°-bis(terpyridine) and an outer extended free 120°-bis(terpyridine) linked by a triple 〈-tpy-Ru2+-tpy-〉 connector, and complexed with Zn2+, gave rise to a discrete planar supramolecular honeycomb patterned fractal. The central metallo-hexagon was surrounded by six identical metallo-hexagons which perfectly mimicked the natural simple honeycomb structure.

15.
Inorg Chem ; 56(7): 4065-4071, 2017 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-28333445

RESUMEN

Three approaches have been carefully examined in order to develop a terpyridine-based dendritic metallotriangle: (1) direct self-assembly of two types of organic polyterpyridines with metal ions; (2) assembly of flexible metallo-organic ligands containing two uncomplexed free terpyridines with a possible 60°-V-shaped orientation; (3) assembly of functionalized metallotriangles possessing a fixed 60°-bent uncoordinated bisterpyridine. Only the third approach has successfully given rise to the desired first-generation dendritic metallotriangle. Structural characterization was accomplished by NMR, ESI-TWIM-MS, and AFM.

16.
Water Res ; 109: 186-195, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-27888775

RESUMEN

We compared water and sanitation system options for a coastal community across selected sustainability metrics, including environmental impact (i.e., life cycle eutrophication potential, energy consumption, and global warming potential), equivalent annual cost, and local human health impact. We computed normalized metric scores, which we used to discuss the options' strengths and weaknesses, and conducted sensitivity analysis of the scores to changes in variable and uncertain input parameters. The alternative systems, which combined centralized drinking water with sanitation services based on the concepts of energy and nutrient recovery as well as on-site water reuse, had reduced environmental and local human health impacts and costs than the conventional, centralized option. Of the selected sustainability metrics, the greatest advantages of the alternative community water systems (compared to the conventional system) were in terms of local human health impact and eutrophication potential, despite large, outstanding uncertainties. Of the alternative options, the systems with on-site water reuse and energy recovery technologies had the least local human health impact; however, the cost of these options was highly variable and the energy consumption was comparable to on-site alternatives without water reuse or energy recovery, due to on-site reuse treatment. Future work should aim to reduce the uncertainty in the energy recovery process and explore the health risks associated with less costly, on-site water treatment options.


Asunto(s)
Calentamiento Global , Saneamiento , Eutrofización , Humanos , Eliminación de Residuos Líquidos/economía , Aguas Residuales , Agua
17.
Opt Lett ; 41(22): 5397-5400, 2016 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-27842141

RESUMEN

A Faraday anomalous dispersion optical filter (FADOF) and an atomic resonant absorption filter are used in tandem to demonstrate a low-frequency shift Raman measurement down to few cm-1. The FADOF, with an ultralow bandwidth of 0.08 cm-1 at 780 nm, serves as a bandpass filter, while the rubidium atomic cell acts as a notch filter which has a bandwidth of 0.3 cm-1. A proof-of-concept study to measure a Raman signal generated from a silica optical fiber is performed, demonstrating a low-frequency measurement of both the Stokes and the anti-Stokes shift down to 3 cm-1 at an equivalent signal level. These results indicate the prospect for gigahertz-terahertz low-energy Raman spectroscopy based on atomic filters.

18.
Sci Rep ; 6: 29882, 2016 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-27418112

RESUMEN

The Faraday anomalous dispersion optical filter (FADOF), which has acquired wide applications, is mainly limited to some gaseous elements and low melting-point metals before, for the restriction of the attainable atomic density. In conventional FADOF systems a high atomic density is usually achieved by thermal equilibrium at the saturated vapor pressure, hence for elements with high melting-points a high temperature is required. To avoid this restriction, we propose a scheme of FADOF based on the hollow cathode lamp (HCL), instead of atomic vapor cells. Experimental results in strontium atoms verified this scheme, where a transmission peak corresponding to the (88)Sr (5s(2))(1)S0 - (5s5p)(1)P1 transition (461 nm) is obtained, with a maximum transmittance of 62.5% and a bandwith of 1.19 GHz. The dependence of transmission on magnetic field and HCL discharge current is also studied. Since the state-of-art commercial HCLs cover about 70 elements, this scheme can greatly expand the applications of FADOFs, and the abundant atomic transitions they provide bring the HCL based FADOFs potential applications for frequency stabilization.

19.
Water Res ; 77: 155-169, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25864006

RESUMEN

Planning for sustainable community water systems requires a comprehensive understanding and assessment of the integrated source-drinking-wastewater systems over their life-cycles. Although traditional life cycle assessment and similar tools (e.g. footprints and emergy) have been applied to elements of these water services (i.e. water resources, drinking water, stormwater or wastewater treatment alone), we argue for the importance of developing and combining the system-based tools and metrics in order to holistically evaluate the complete water service system based on the concept of integrated resource management. We analyzed the strengths and weaknesses of key system-based tools and metrics, and discuss future directions to identify more sustainable municipal water services. Such efforts may include the need for novel metrics that address system adaptability to future changes and infrastructure robustness. Caution is also necessary when coupling fundamentally different tools so to avoid misunderstanding and consequently misleading decision-making.


Asunto(s)
Conservación de los Recursos Naturales , Eliminación de Residuos Líquidos/métodos , Recursos Hídricos/provisión & distribución , Planificación de Ciudades , Monitoreo del Ambiente , Modelos Teóricos , Abastecimiento de Agua/métodos , Abastecimiento de Agua/estadística & datos numéricos
20.
ScientificWorldJournal ; 2015: 614737, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25734183

RESUMEN

Considering the strong inhomogeneous spatial polarization and intensity distribution of spontaneous decay fluorescence due to the Hanle effect, we propose and demonstrate a universe Hanle detection configuration of electron-shelving method for optical clocks. Experimental results from Ca atomic beam optical frequency standard with electron-shelving method show that a designed Hanle detection geometry with optimized magnetic field direction, detection laser beam propagation and polarization direction, and detector position can improve the fluorescence collection rate by more than one order of magnitude comparing with that of inefficient geometry. With the fixed 423 nm fluorescence, the improved 657 nm optical frequency standard signal intensity is presented. The potential application of the Hanle detection geometry designed for facilitating the fluorescence collection for optical lattice clock with a limited solid angle of the fluorescence collection has been discussed. The Hanle detection geometry is also effective for ion detection in ion optical clock and quantum information experiments. Besides, a cylinder fluorescence collection structure is designed to increase the solid angle of the fluorescence collection in Ca atomic beam optical frequency standard.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA