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1.
Thyroid ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38757581

RESUMEN

Background: Although childhood exposure to radioactive iodine-131 (I-131) is an established risk factor for thyroid cancer, evidence for an association with thyroid nodules is less clear. The objective of this study is to evaluate the association between childhood I-131 exposure and prevalence of ultrasound-detected thyroid nodules overall and by nodule histology/cytology (neoplastic/suspicious/non-neoplastic), size (<10 mm/≥10 mm), and number (single/multiple). Methods: This is a cross-sectional study of radiation dose (mean = 0.53 gray, range: 0.0003-31 gray) and screen-detected thyroid nodules conducted in 1998-2000 (median population age 21.5 years) in a cohort of 13,243 residents of Ukraine who were under 18 years at the time of the Chornobyl accident on April 26, 1986. Excess odds ratios per gray (excess odds ratio [EOR]/Gy) and confidence intervals (CIs) were estimated using logistic regression. Results: Among 13,078 eligible individuals, we identified 358 (2.7%) with at least one thyroid nodule. Significantly increased dose-response associations were found for all nodules and nodule groups with doses <5 Gy except individuals with non-neoplastic nodules. Among individuals with doses <5 Gy, the EOR/Gy for neoplastic nodules (5.35; CI: 2.19-15.5) was significantly higher than for non-neoplastic nodules (0.24; CI: 0.07-0.74), but the EOR/Gy did not vary by nodule size or number. Conclusions: Childhood exposure to I-131 is associated with an increased risk of thyroid nodules detected 12-14 years following exposure, and the risk for neoplastic nodules is higher than for non-neoplastic nodules. Analyses of incident thyroid nodules may help clarify dose-response patterns by nodule characteristics and provide insights into thyroid nodule etiology.

2.
Opt Lett ; 49(7): 1794-1797, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38560865

RESUMEN

In this work, we design and experimentally demonstrate the first, to the best of our knowledge, integrated polarization splitters and rotators at blue wavelengths. We develop compact and efficient designs for both a polarization splitter and rotator at a 422-nm wavelength, an important laser-cooling transition for 88Sr+ ions. These devices are fabricated in a 200-mm wafer-scale process and experimentally demonstrated, resulting in a measured polarization-splitter transverse-electric thru-port coupling of 98.0% and transverse-magnetic tap-port coupling of 77.6% for a compact 16-µm-long device and a polarization-rotator conversion efficiency of 92.2% for a separate compact 111-µm-long device. This work paves the way for more sophisticated integrated control of trapped-ion and neutral-atom quantum systems.

3.
Acta Cytol ; 68(1): 34-44, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38246154

RESUMEN

INTRODUCTION: The Chernobyl nuclear accident exposed residents of contaminated territories to substantial quantities of radioiodines and was followed by an increase in thyroid cancer, primarily papillary thyroid cancer (PTC), among exposed children and adolescents. Although thyroid biopsy is an essential component of screening programs following accidental exposure to radioiodines, it is unknown whether the predictive value of biopsy is affected by different levels of environmental exposure. METHODS: A cohort of 11,732 Belarusians aged ≤18 years at the time of the Chernobyl accident with individual thyroid radiation dose estimates was screened at least once 11-22 years later. Paired cytologic conclusions and histopathologic diagnoses were possible for 258 thyroid nodules from 238 cohort members. Cytologic conclusions were divided into five reporting categories, with all follicular lesion aspirates combined into a single indeterminate category. Standard performance indicators, risk of malignancy (ROM), and odds ratios for a correct cytologic conclusion were calculated, both overall and according to quintile of thyroid radiation dose. RESULTS: The arithmetic mean thyroid dose estimate for the study group was 1.73 Gy (range: 0.00-23.64 Gy). The final histopathologic diagnosis was cancer for 136 of 258 biopsies (52.7%; 135 papillary and 1 follicular). The overall ROM was 96.7% for cytologies definite for PTC, 83.7% for suspicious for PTC, 33.0% for indeterminate, 8.1% for benign, and 31.0% for non-diagnostic. The ROM showed little change according to level of radiation exposure. Overall, there was no association between thyroid radiation dose and the odds ratio for a correct cytologic conclusion (p = 0.24). When analyzed according to dose quintile, the odds ratio for a correct conclusion increased two-fold at 0.10-0.29 Gy compared to a dose of 0.00-0.09 Gy and decreased at doses of 0.3-24 Gy (p value for linear trend = 0.99). CONCLUSIONS: At radiation doses received by a cohort of young Belarusians exposed to radioiodines by the Chernobyl accident, the predictive value of thyroid biopsy for diagnosing PTC was not significantly affected by level of radiation exposure.


Asunto(s)
Carcinoma Papilar , Accidente Nuclear de Chernóbil , Pueblos de Europa Oriental , Neoplasias de la Tiroides , Adolescente , Niño , Humanos , Biopsia , Carcinoma Papilar/patología , Dosis de Radiación , Cáncer Papilar Tiroideo/diagnóstico , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/patología , Adulto
4.
Phys Rev Lett ; 131(17): 170602, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37955505

RESUMEN

We present experimental demonstrations of accurate and unambiguous single-shot discrimination between three quantum channels using a single trapped ^{40}Ca^{+} ion. The three channels cannot be distinguished unambiguously using repeated single channel queries, the natural classical analogue. We develop techniques for using the six-dimensional D_{5/2} state space for quantum information processing, and we implement protocols to discriminate quantum channel analogues of phase shift keying and amplitude shift keying data encodings used in classical radio communication. The demonstrations achieve discrimination accuracy exceeding 99% in each case, limited entirely by known experimental imperfections.

5.
Opt Express ; 31(16): 25507-25514, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37710435

RESUMEN

The use of averaging has long been known to reduce noise in statistically independent systems that exhibit similar levels of stochastic fluctuation. This concept of averaging is general and applies to a wide variety of physical and man-made phenomena such as particle motion, shot noise, atomic clock stability, measurement uncertainty reduction, and methods of signal processing. Despite its prevalence in use for reducing statistical uncertainty, such averaging techniques so far remain comparatively undeveloped for application to light. We demonstrate here a method for averaging the frequency uncertainty of identical laser systems as a means to narrow the spectral linewidth of the resulting radiation. We experimentally achieve a reduction of frequency fluctuations from 40 Hz to 28 Hz by averaging two separate laser systems each locked to a fiber resonator. Only a single seed laser is necessary here as acousto-optic modulation is used to enable independent control of the second path. This technique of frequency averaging provides an effective solution to overcome the linewidth constraints of a single laser alone, particularly when limited by fundamental noise sources such as thermal noise, irrespective of the spectral shape of noise.

6.
BMJ Support Palliat Care ; 13(e2): e291-e293, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-33593869

RESUMEN

A 62-year-old man with metastatic duodenal cancer was admitted to a hospice for a trial of ketamine to manage complex neuropathic abdominal pain. The patient was incrementally established on a dose of 150 mg orally four times day with no adverse effects. Following treatment of hypomagnesaemia intravenously, the patient experienced marked symptoms of ketamine toxicity, known as a 'K-hole' amongst recreational users, following the next dose of ketamine. Ketamine and magnesium are both antagonists of the N-methyl-D-aspartate receptor, which plays a part in central sensitisation to pain. There is some evidence that correction of hypomagnesaemia may improve analgesia and that there is synergism between ketamine and magnesium in analgesia, but this relationship is poorly understood. This is the first report suggesting that blood magnesium levels may affect the side effects of a stable dose of ketamine.


Asunto(s)
Analgesia , Ketamina , Neuralgia , Masculino , Humanos , Persona de Mediana Edad , Ketamina/efectos adversos , Magnesio/uso terapéutico , Neuralgia/inducido químicamente , Neuralgia/tratamiento farmacológico , Analgésicos/efectos adversos
7.
Artículo en Inglés | MEDLINE | ID: mdl-36522142

RESUMEN

OBJECTIVES: Palliative care needs to embrace research to guide service development and effective symptom management. Healthcare professionals often feel research is too burdensome for patients who have poor performance status or are near the end of life. Many studies exclude these groups from participating.We aimed to identify whether specialist palliative care inpatients would wish to take part in research and whether preference varies according to study design, demographics, diagnosis, performance status and prognosis. METHODS: 100 inpatients in two National Health Service specialist palliative care units and one independent hospice in the Northeast of England completed a short questionnaire about preferences for involvement in research. RESULTS: 92% of participants stated they were interested in being involved in research. This was mostly unaffected by age, diagnosis, prognosis, performance and socioeconomic status. Three-quarters were within the last 3 months of life. Simple questions or interviews were the preferred methodology, whereas only half of patients would want further investigations or additional medications and fewer still wanted to participate in online activities, lifestyle change or group activities. CONCLUSIONS: Palliative care inpatients welcome the opportunity to be involved in research and should not be excluded on the grounds of advanced disease, poor prognosis and low performance status.

8.
Opt Express ; 30(13): 22562-22571, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-36224951

RESUMEN

Photonically integrated resonators are promising as a platform for enabling ultranarrow linewidth lasers in a compact form factor. Owing to their small size, these integrated resonators suffer from thermal noise that limits the frequency stability of the optical mode to ∼100 kHz. Here, we demonstrate an integrated stimulated Brillouin scattering (SBS) laser based on a large mode-volume annulus resonator that realizes an ultranarrow thermal-noise-limited linewidth of 270 Hz. In practice, yet narrower linewidths are required before integrated lasers can be truly useful for applications such as optical atomic clocks, quantum computing, gravitational wave detection, and precision spectroscopy. To this end, we employ a thermorefractive noise suppression technique utilizing an auxiliary laser to reduce our SBS laser linewidth to 70 Hz. This demonstration showcases the possibility of stabilizing the thermal motion of even the narrowest linewidth chip lasers to below 100 Hz, thereby opening the door to making integrated microresonators practical for the most demanding future scientific endeavors.

9.
Phys Rev Lett ; 129(10): 100502, 2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36112432

RESUMEN

Integrated technologies greatly enhance the prospects for practical quantum information processing and sensing devices based on trapped ions. High-speed and high-fidelity ion state readout is critical for any such application. Integrated detectors offer significant advantages for system portability and can also greatly facilitate parallel operations if a separate detector can be incorporated at each ion-trapping location. Here, we demonstrate ion quantum state detection at room temperature utilizing single-photon avalanche diodes (SPADs) integrated directly into the substrate of silicon ion trapping chips. We detect the state of a trapped Sr^{+} ion via fluorescence collection with the SPAD, achieving 99.92(1)% average fidelity in 450 µs, opening the door to the application of integrated state detection to quantum computing and sensing utilizing arrays of trapped ions.

10.
Environ Health ; 21(1): 5, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34996456

RESUMEN

BACKGROUND: While there is a robust literature on environmental exposure to iodine-131 (131I) in childhood and adolescence and the risk of thyroid cancer and benign nodules, little is known about its effects on thyroid volume. METHODS: To assess the effect of 131I dose to the thyroid on the volume of the thyroid gland, we examined the data from the baseline screening of the Belarusian-American Cohort Study of residents of Belarus who were exposed to the Chernobyl fallout at ages ≤18 years. Thyroid dose estimates were based on individual thyroid activity measurements made shortly after the accident and dosimetric data from questionnaires obtained 10-15 years later at baseline screening. During baseline screening, thyroid gland volume was assessed from thyroid ultrasound measurements. The association between radiation dose and thyroid volume was modeled using linear regression where radiation dose was expressed with power terms to address non-linearity. The model was adjusted for attained age, sex, and place of residence, and their modifying effects were examined. RESULTS: The analysis was based on 10,703 subjects. We found a statistically significant positive association between radiation dose and thyroid volume (P < 0.001). Heterogeneity of association was observed by attained age (P < 0.001) with statistically significant association remaining only in the subgroup of ≥18 years at screening (P < 0.001). For this group, increase in dose from 0.0005 to 0.15 Gy was associated with a 1.27 ml (95% CI: 0.46, 2.07) increase in thyroid volume. The estimated effect did not change with increasing doses above 0.15 Gy. CONCLUSIONS: This is the first study to examine the association between 131I dose to the thyroid gland and thyroid volume in a population of individuals exposed during childhood and systematically screened 10-15 years later. It provides evidence for a moderate statistically significant increase in thyroid volume among those who were ≥ 18 years at screening. Given that this effect was observed at very low doses and was restricted to a narrow dose range, further studies are necessary to better understand the effect.


Asunto(s)
Accidente Nuclear de Chernóbil , Neoplasias Inducidas por Radiación , Neoplasias de la Tiroides , Adolescente , Estudios de Cohortes , Relación Dosis-Respuesta en la Radiación , Humanos , Radioisótopos de Yodo/efectos adversos , República de Belarús/epidemiología , Neoplasias de la Tiroides/epidemiología , Ucrania
11.
Nature ; 588(7837): 244-249, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33299197

RESUMEN

Microwave atomic clocks have traditionally served as the 'gold standard' for precision measurements of time and frequency. However, over the past decade, optical atomic clocks1-6 have surpassed the precision of their microwave counterparts by two orders of magnitude or more. Extant optical clocks occupy volumes of more than one cubic metre, and it is a substantial challenge to enable these clocks to operate in field environments, which requires the ruggedization and miniaturization of the atomic reference and clock laser along with their supporting lasers and electronics4,7,8,9. In terms of the clock laser, prior laboratory demonstrations of optical clocks have relied on the exceptional performance gained through stabilization using bulk cavities, which unfortunately necessitates the use of vacuum and also renders the laser susceptible to vibration-induced noise. Here, using a stimulated Brillouin scattering laser subsystem that has a reduced cavity volume and operates without vacuum, we demonstrate a promising component of a portable optical atomic clock architecture. We interrogate a 88Sr+ ion with our stimulated Brillouin scattering laser and achieve a clock exhibiting short-term stability of 3.9 × 10-14 over one second-an improvement of an order of magnitude over state-of-the-art microwave clocks. This performance increase within a potentially portable system presents a compelling avenue for substantially improving existing technology, such as the global positioning system, and also for enabling the exploration of topics such as geodetic measurements of the Earth, searches for dark matter and investigations into possible long-term variations of fundamental physics constants10-12.

12.
Artículo en Inglés | MEDLINE | ID: mdl-32958503

RESUMEN

Long-term dependence on non-invasive ventilation (NIV) without time for advance care planning can result in significant complications that may require innovative management strategies. We present the case of a man who was admitted with respiratory failure and required NIV. Despite effective treatment for community acquired pneumonia, attempts to wean NIV failed. While dependent on NIV, a diagnosis of motor neuron disease was made. Time without ventilation was not tolerated and consequently complications of: facial pressure ulceration, nasal septal prolapse, inspissated secretions and failure to feed occurred. This case illustrates the severity of complications that can result from NIV dependence; however, it also details how these can be effectively managed by the hospice multidisciplinary team, with support from experts both within and external to the hospice enabling the acquisition of appropriate skills and knowledge.

13.
Br J Neurosurg ; 34(3): 339-341, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29433336

RESUMEN

Spinal Atypical Teratoid/Rhabdoid Tumour (AT/RT) is a highly malignant tumour, and its prognosis is dismal especially for very young patients. In this article, we present the case of a teenage boy with AT/RT in the cervical spine and its multimodality management. A review of the literature on ATRT of the spine is also presented.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Tumor Rabdoide , Teratoma , Adolescente , Humanos , Masculino , Pronóstico , Tumor Rabdoide/diagnóstico por imagen , Tumor Rabdoide/cirugía , Columna Vertebral , Teratoma/diagnóstico por imagen , Teratoma/cirugía
14.
Oncologist ; 25(5): 398-403, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31740569

RESUMEN

BACKGROUND: Ultrasound plays a critical role in evaluating thyroid nodules. We compared the performance of the two most popular ultrasound malignancy risk stratification systems, the 2015 American Thyroid Association (ATA) guidelines and the American College of Radiology Thyroid Imaging and Reporting Data System (ACR TI-RADS). MATERIALS AND METHODS: We retrospectively identified 250 thyroid nodules that were surgically removed from 137 patients. Their ultrasound images were independently rated using both ATA and ACR TI-RADS by six raters with expertise in ultrasound interpretation. For each system, we generated a receiver operating characteristic curve and calculated the area under the curve (AUC). RESULTS: Sixty-five (26%) nodules were malignant. There was "fair agreement" among raters for both ATA and ACR TI-RADS. Our observed malignancy risks for ATA and ACR TI-RADS categories were similar to expected risk thresholds with a few notable exceptions including the intermediate ATA risk category and the three highest risk categories for ACR TI-RADS. Biopsy of 226 of the 250 nodules would be indicated by ATA guidelines based on nodule size and mean ATA rating. One hundred forty-six nodules would be biopsied based on ACR TI-RADS. The sensitivity, specificity, and negative and positive predictive values were 92%, 10%, 79%, and 27%, respectively, for ATA and 74%, 47%, 84%, and 33%, respectively, for ACR TI-RADS. The AUC for ATA was 0.734 and for ACR TI-RADS was 0.718. CONCLUSION: Although both systems demonstrated good diagnostic performance, ATA guidelines resulted in a greater number of thyroid biopsies and exhibited more consistent malignancy risk prediction for higher risk categories. IMPLICATIONS FOR PRACTICE: With the rising incidence of thyroid nodules, the need for accurate detection of malignancy is important to avoid the overtreatment of benign nodules. Ultrasonography is one of the key tools for the evaluation of thyroid nodules, although the use of many different ultrasound risk stratification systems is a hindrance to clinical collaboration in everyday practice and the comparison of data in research. The first step toward the development of a universal thyroid nodule ultrasound malignancy risk stratification system is to better understand the strengths and weaknesses of the current systems in use.


Asunto(s)
Radiología , Neoplasias de la Tiroides , Nódulo Tiroideo , Sistemas de Datos , Humanos , Estudios Retrospectivos , Medición de Riesgo , Glándula Tiroides/diagnóstico por imagen , Nódulo Tiroideo/diagnóstico por imagen , Ultrasonografía , Estados Unidos
15.
AWWA Water Sci ; 1(1): e1125, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31001606

RESUMEN

The U.S. Safe Drinking Water Act required states to develop source water assessment programs identifying existing and potential contamination sources; however, comprehensive risk prioritization and management approaches for surface water supplies have seen limited application. This participatory study assessed which permutation(s) of risk management frameworks and tools might benefit U.S. utilities by combining a literature review with external utility interviews. Qualitative data provided a basis for categorical assignments of goodness of fit with each of 24 framework evaluation criteria across five categories. Weighted integration using stakeholder input provided a relative ranking of applicability, later validated at a decision-making workshop. Hybridization of the American National Standards Institute/American Water Works Association (ANSI/AWWA G300) source water protection standard and World Health Organization Water Safety Plan guidance was recommended to develop a comprehensive risk management approach for U.S. source waters. Cost-benefit components of other guidance materials were recommended to incorporate financial considerations into risk ranking and mitigation decisions.

16.
Clin Chem Lab Med ; 56(5): 796-802, 2018 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-29220880

RESUMEN

BACKGROUND: Apolipoprotein E (APOE) is a key player in lipid transport and metabolism and exists in three common isoforms: APOE2, APOE3 and APOE4. The presence of the E4 allelic variant is recognized as a major genetic risk factor for dementia and other chronic (neuro)degenerative diseases. The availability of a validated assay for rapid and reliable APOE4 classification is therefore advantageous. METHODS: Biochip array technology (BAT) was successfully applied to identify directly the APOE4 status from plasma within 3 h, through simultaneous immunoassay-based detection of both specific APOE4 and total APOE levels. RESULTS: Samples (n=432) were first genotyped by polymerase chain reaction (PCR), and thereafter, using BAT, the corresponding plasma was identified as null, heterozygous or homozygous for the E4 allele by calculating the ratio of APOE4 to total APOE protein. Two centers based in Austria and Ireland correctly classified 170 and 262 samples, respectively, and achieved 100% sensitivity and specificity. CONCLUSIONS: This chemiluminescent biochip-based sandwich immunoarray provides a novel platform to detect rapidly and accurately an individual's APOE4 status directly from plasma. The E4 genotype of individuals has been shown previously to affect presymptomatic risk, prognosis and treatment response for a variety of diseases, including Alzheimer's disease. The biochip's potential for being incorporated in quantitative protein biomarker arrays capable of analyzing disease stages makes it a superior alternative to PCR-based APOE genotyping and may deliver additional protein-specific information on a variety of diseases in the future.


Asunto(s)
Apolipoproteína E4/sangre , Inmunoensayo , Mediciones Luminiscentes , Anciano , Anciano de 80 o más Años , Alelos , Apolipoproteína E4/genética , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
17.
Environ Res ; 156: 801-809, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28505591

RESUMEN

BACKGROUND: Serum thyroglobulin (Tg) is associated with the presence of thyroid disease and has been proposed as a biomarker of iodine status. Few studies have examined factors related to serum Tg in populations environmentally exposed to ionizing radiation and living in regions with endemic mild-to-moderate iodine deficiency. METHODS: We screened 10,430 individuals who were living in Ukraine and under 18 years of age at the time of the 1986 Chernobyl Nuclear Power Plant accident for thyroid disease from 2001 to 2003. We estimated the percent change (PC) in serum Tg associated with demographic factors, iodine-131 thyroid dose, and indicators of thyroid structure and function using linear regression. We also examined these relationships for individuals with and without indications of thyroid abnormality. RESULTS: Mean and median serum Tg levels were higher among participants with abnormal thyroid structure/function. Percent change in serum Tg increased among females, smokers and with older age (p-values<0.001), and Tg increased with increasing thyroid volume, and serum thyrotropin (p-values for trend<0.001). We found no evidence of significant associations between iodine-131 thyroid dose and Tg. Serum Tg levels were inversely associated with iodized salt intake (PC=-7.90, 95% confidence interval: -12.08, -3.52), and over the range of urinary iodine concentration, the odds of having elevated serum Tg showed a U-shaped curve with elevated Tg at low and high urinary iodine concentrations. CONCLUSION: Serum Tg may be a useful indicator of population iodine status and a non-specific biomarker of structural and functional thyroid abnormalities in epidemiological studies.


Asunto(s)
Accidente Nuclear de Chernóbil , Radioisótopos de Yodo , Exposición a la Radiación , Tiroglobulina/sangre , Adolescente , Adulto , Factores de Edad , Dieta , Femenino , Humanos , Yodo/orina , Masculino , Dosis de Radiación , Fumar/sangre , Fumar/orina , Glándula Tiroides/anatomía & histología , Tirotropina/sangre , Ucrania , Adulto Joven
18.
J Clin Endocrinol Metab ; 102(7): 2207-2217, 2017 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28368520

RESUMEN

Context: Although radiation exposure is an important predictor of thyroid cancer on diagnosis of a thyroid nodule, the relationship between childhood radiation exposure and thyroid nodules has not been comprehensively evaluated. Objective: To examine the association between internal I-131 thyroid dose and thyroid nodules in young adults exposed during childhood. Design, setting, and participants: In this cross-sectional study, we screened residents of Belarus aged ≤18 years at the time of the Chernobyl nuclear accident for thyroid disease (median age, 21 years) with thyroid palpation, ultrasonography, blood/urine analysis, and medical follow-up when appropriate. Eligible participants (N = 11,421) had intact thyroid glands and doses based on direct individual thyroid activity measurements. Main outcome measures: Excess odds ratios per Gray (EOR/Gy, scaled at age 5 years at exposure) for any thyroid nodule and for nodules grouped by cytology/histology, diameter size, and singularity. Results: Risk of any thyroid nodule increased significantly with I-131 dose and, for a given dose, with younger age at exposure. The EOR/Gy (95% confidence intervals) for neoplastic nodules (3.82; 0.87 to 15.52) was significantly higher than for nonneoplastic nodules (0.32; <0.03 to 0.70) and did not vary by size; whereas the EOR/Gy for nonneoplastic nodules did vary by size (P = 0.02) and was 1.55 (0.36 to 5.46) for nodules ≥10 mm and 0.02 (<-0.02 to 0.70) for nodules <10 mm. EORs/Gy for single and multiple nodules were comparable. Conclusions: Childhood exposure to internal I-131 is associated with increased risk of neoplastic thyroid nodules of any size and nonneoplastic nodules ≥10 mm.


Asunto(s)
Accidente Nuclear de Chernóbil , Neoplasias Inducidas por Radiación/etiología , Nódulo Tiroideo/etiología , Adolescente , Niño , Preescolar , Relación Dosis-Respuesta en la Radiación , Detección Precoz del Cáncer/métodos , Femenino , Humanos , Lactante , Recién Nacido , Radioisótopos de Yodo/efectos adversos , Masculino , Neoplasias Inducidas por Radiación/epidemiología , República de Belarús/epidemiología , Medición de Riesgo/métodos , Factores de Riesgo , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/epidemiología , Nódulo Tiroideo/patología , Ultrasonografía
19.
Nat Nanotechnol ; 11(12): 1066-1070, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27501316

RESUMEN

The long coherence times and strong Coulomb interactions afforded by trapped ion qubits have enabled realizations of the necessary primitives for quantum information processing and the highest-fidelity quantum operations in any qubit to date. Although light delivery to each individual ion in a system is essential for general quantum manipulations and readout, experiments so far have employed optical systems that are cumbersome to scale to even a few tens of qubits. Here we demonstrate lithographically defined nanophotonic waveguide devices for light routing and ion addressing that are fully integrated within a surface-electrode ion trap chip. Ion qubits are addressed at multiple locations via focusing grating couplers emitting through openings in the trap electrodes to ions trapped 50 µm above the chip; using this light, we perform quantum coherent operations on the optical qubit transition in individual 88Sr+ ions. The grating focuses the beam to a diffraction-limited spot near the ion position with 2 µm 1/e2 radius along the trap axis, and we measure crosstalk errors between 10-2 and 4 × 10-4 at distances 7.5-15 µm from the beam centre. Owing to the scalability of the planar fabrication technique employed, together with the tight focusing and stable alignment afforded by the integration of the optics within the trap chip, this approach presents a path to creating the optical systems required for large-scale trapped-ion quantum information processing.

20.
Nat Commun ; 7: 13005, 2016 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-27677357

RESUMEN

Two-dimensional arrays of trapped-ion qubits are attractive platforms for scalable quantum information processing. Sufficiently rapid reloading capable of sustaining a large array, however, remains a significant challenge. Here with the use of a continuous flux of pre-cooled neutral atoms from a remotely located source, we achieve fast loading of a single ion per site while maintaining long trap lifetimes and without disturbing the coherence of an ion quantum bit in an adjacent site. This demonstration satisfies all major criteria necessary for loading and reloading extensive two-dimensional arrays, as will be required for large-scale quantum information processing. Moreover, the already high loading rate can be increased by loading ions in parallel with only a concomitant increase in photo-ionization laser power and no need for additional atomic flux.

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