Under seeing limited conditions very high resolution spectroscopy becomes very difficult for extremely large telescopes (ELTs). Using adaptive optics (AO) the stellar image size decreases proportional with the telescope diameter. This makes the spectrograph optics and hence its resolution independent of the telescope diameter. However AO for use with ELTs at visible wavelengths require deformable mirrors with many elements. Those are not likely to be available for quite some time. We propose to use the pupil slicing technique to create a number of sub-pupils each of which having its own deformable mirror. The images from all sub-pupils are combined incoherently with a diameter corresponding to the diffraction limit of the sub-pupil. The technique is referred to as "Pupil Slicing Adaptive Optics" or PSAO.
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http://dx.doi.org/10.1364/oe.15.001983 | DOI Listing |
Nano Lett
January 2025
Key Lab for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics, School of Electronics, Peking University, Beijing 100871, China.
One-time programmable (OTP) memory is an essential component in chips, which has extremely high security to protect the stored critical information from being altered. However, traditional OTP memory based on the thermal breakdown of the dielectric has a large programming current, which leads to high power consumption. Here, we report a gate tunneling-induced "cold" breakdown phenomenon in carbon nanotube (CNT) field-effect transistors, and based on this we construct a "cold" fuse (C-fuse) memory where applying a mild gate voltage can break down the CNT channel without damaging the gate dielectric.
View Article and Find Full Text PDFAlkaptonuria (AKU) is an extremely rare autosomal recessive metabolic disorder caused by deficiency of homogentisic acid oxidase and resulting in accumulation of homogentisic acid in collagenous structures. It is characterized by a triad of homogentisic aciduria, bluish-black discoloration of connective tissues (ochronosis) and arthropathy of large weight bearing joints. We report on a middle-aged female patient with bilateral severe ochronotic arthritis of both hips and shoulder joints requiring total joint replacements as staged procedures which were done without complications offering a complete pain relief and a satisfactory clinical and functional outcome.
View Article and Find Full Text PDFPurpose: To examine the physiological, power-duration, nutritional intake and training characteristics of the recent lightweight (- 75 kg) 50+, 60+ and 70 + yr world champion indoor rowers.
Methods: Laboratory assessments, undertaken over 2 visits, examined body composition, pulmonary function, blood lactate/ventilatory landmarks, efficiency, fat/carbohydrate oxidation, primary component time-constant to steady-state [𝜏pc]) and peak oxygen consumption (V̇O2peak). Training, performance and nutritional intake were also reported.
Pediatr Res
January 2025
Division of Neonatal and Developmental Medicine, Department of Pediatrics, Stanford University School of Medicine, Palo Alto, CA, USA.
Background: Unbound bilirubin (UB) was measured on day 5 ± 1 in 1101 ELBW newborns in the Aggressive vs Conservative Phototherapy randomized controlled trial. We accessed this dataset to quantify the UB-mediated risk of severe neurodevelopmental impairment (sNDI) in extremely low birthweight (ELBW) newborns.
Methods: UB levels were standardized within laboratories as z-score percentiles.
Heart
January 2025
Department of Environmental Health, Harvard T H Chan School of Public Health, Boston, Massachusetts, USA.
Background: Kuwait, one of the world's hottest countries, faces increasing temperatures due to climate change. With a large migrant population predominantly employed in physically demanding jobs, the exact effects and burdens of temperature exposure on cardiovascular risk among this population remain unknown. This study aimed to investigate the relationship between temperature and myocardial infarction (MI) risk among migrants in Kuwait.
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