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The first time astrophysicists detected a planet outside of our Solar System around a Sunlike star was in 1995, and since then, more than 5,000 extrasolar planets (or exoplanets) have [...]

Loop-Mediated Isothermal Loop-Mediated Isothermal Amplification (LAMP) is a widely used technique for nucleic acid amplification due to its high specificity, sensitivity, and rapid results. Advances in microfluidic lab-on-chip (LOC) technology have enabled the integration of LAMP into miniaturized devices, known as μ -LAMP, which require precise thermal control for optimal DNA amplification. This paper introduces a novel thermal bed design using PCB copper traces and F R − 4 dielectric materials, providing a reliable, modular, and repairable heating platform. The system achieves accurate and stable temperature control, which is critical for μ -LAMP applications, with temperature deviations within ±1.0 °C. The thermal bed's performance is validated through finite element method (FEM) simulations, showing uniform temperature distribution and a rapid thermal response of 2.5 s to reach the target temperature. These results highlight the system's potential for applications such as disease diagnostics, biological safety, and forensic analysis, where precision and reliability are paramount. [ABSTRACT FROM AUTHOR]

We previously proposed that the optical centroid efficiency (OCE) might be a preferred figure-of-merit to the enclosed energy of a rectangular pixel (EOD) for an instrument subject to unpredictable environmental jitter and alignment conditions. Here we follow the same symbols for the corresponding quantities, particularly the width of the pixel as being equal to 2d. Here we analyze the performance of the OCE vs. the EOD for the three Seidel primary aberrations of an optical component: spherical, coma, and astigmatism, plus defocus. We show that the OCE has an approximate U-shape when graphed against the EOD, for the aberrations ranging from 0 to 1.25λ. We conclude that for pixels larger than 2d = 3λF/#, a small pixel will feature better performance when expecting jitter, misalignment, and other environmental and unpredictable conditions. When evaluating the performance of low-aberration instruments in dynamic and unpredictable environments, the choice of the lager pixel 2d = 7λF/# might be advantageous. Its selection will result in the deterioration of image resolution. [ABSTRACT FROM AUTHOR]

Over the past few years, one can scarcely open a prestigious national magazine or newsletter without coming across a sordid story about plagiarism at the highest echelons of science. There [...]

Sigma Xi is a multidisciplinary scientific research honor society that champions the principles of ethical scientific research and calls on members to introduce future scientists to the responsibilities incumbent in [...]

In the world of mice, with whom humans share a common ancestor according to one theory of evolution, an interesting experiment was performed more than 15 years ago. In the [...]

Paul was a particularly bright student. On the day of the defense of his doctoral dissertation, just before his committee started deliberations, I opened questions to the public. I am [...]

We describe the degradation states of vegetation using a CMOS camera with NIR narrow band filters. Infrared bands provide vegetation parameters through reflectance, such as the water content and the cell order inside the leaf. Therefore, we can observe cellulose decomposition. We observe these parameters by measuring the differential reflectance between 766 nm and 1064 nm. We conclude that the NIR narrow bands add essential information to distinguish the water content and the decomposition of vegetation. [ABSTRACT FROM AUTHOR]

The noise-equivalent power is used to predict performance of infrared (IR) sensors. In a general IR or remote sensing system, the axes of the incoming chief ray of each pixel in the optical system and the center of that detector pixel are slightly misaligned, due to optical tolerances, jitter, and other environmental conditions, leading to error in the sensor performance prediction and estimates. A new figure-of-merit, the optical centroid efficiency (OCE), considers the energy on the rectangular detector pixel, averaged over all positions on the pixel. We calculate the OCE as a function of energy on detector (EOD) for a popular IR imaging system, a three-mirror reflector. [ABSTRACT FROM AUTHOR]

Optical centroid efficiency (OCE) is the traditional enclosed energy by the square detector pixel (the energy on detector (EOD)) averaged over all misalignments between the optical system and the pixel center. We examine the relationship between the OCE and the EOD for two different pixel sizes, with one larger than the diameter of the Airy disc and the other smaller than three diameters of the Airy disc. We observed that the relationships could, in general, be described as having a U shape, with the OCE being proportional to the EOD for small amounts of aberrations and inversely proportional for large amounts. For the letter cases, the energy is distributed over several pixels. [ABSTRACT FROM AUTHOR]

The 17th International Workshop on Advanced Infrared Technology and Applications (AITA 2023) was held in Venice, Italy from 10-13 September 2023. The conference, which has been running since 1992, aims to assess the state of the art of infrared technology and present its applications. The event was organized by various institutions and received patronage from two organizations. The technical program included sessions on topics such as non-destructive testing, sensors, image processing, remote sensing, and biomedical applications. A plenary lecture was given on the role of light in infrared astronomy. The conference also featured the sixth Under 35 Best Paper Award, which was given to three authors for their contributions. The event received support from Teledyne FLIR and Telops. The 18th edition of AITA is scheduled to take place in Kobe, Japan in 2025. [Extracted from the article]

We evaluate the sensitivity and thermal resolution of the fluorescence of europium (III) thenoyltrifluoroacetonate (EuTTA) in order to convert absorbed thermal radiation into visible. We analyze the variation of the fluorescence properties of EuTTA (specifically, amplitude power and lifetime) after absorbed thermal radiation has caused a change in the local temperature of the material. We propose to analyze the thermal dependence of the fluorescence decay with an integral functional. Such operation correlates the variations of lifetime and amplitude in a single value. With this method of analysis, we study one parameter with increased thermal resolution and linear temperature dependence. The thermal resolution achieved with amplitude power is 0.11 K and with lifetime is 0.83 K at 305 K. The sensitivity of the integral functional is 25 nJ/K, yielding an increased thermal resolution of 0.07 K. OCIS codes: 120.6780, 160.1890, 160.2540.

A segmented or diluted aperture optical system will undergo phase errors as a result of errors in the positioning of the segments. The errors associated with a segmented primary mirror limit the image quality obtainable with synthetic aperture telescopes. Here we study the effects of segmentation errors on image quality, considering both the phase angle and the amplitude of the optical transfer function (OTF). We show that, in these kinds of telescope, phasing and alignment errors among segments reduce the amplitude and distort the phase angle of the OTF. OCIS codes: 110.6770, 110.4100, 110.4850.

A new method of phase determination from a single undersampled interferogram is described. Two low-fringe-density synthetic interferograms corresponding to the phase differences along orthogonal directions are obtained from neighboring pixels of the aliased measured data. The only assumption is that the illumination background, the modulation intensity, and the searched phase are smooth and continuous functions. The synthetic interferograms are demodulated by use of either standard frequency or spatial-domain procedures to obtain the phase differences. The phase is then recovered by integration of the phase differences with a least-squares method. The proposed method is demonstrated to be noise tolerant. OCIS codes: 120.0120, 120.2650, 120.3180, 120.5050, 120.6650, 220.4840.

We use the point spread function and the modulation transfer function (MTF) as two figures-of-merit to evaluate the performance of the multiaperture interferometric configurations for the detection of a faint planet in the vicinity of its bright star. We design nonredundant interferometric layouts that provide satisfactory coverage of the spatial frequencies of interest. We propose a design incorporating a rotating, rotationally shearing interferometer in a gravity-free environment and compare its performance with the Earth-based, fixed, linear configurations. The side peak of its MTF may be centered on the coordinate associated with a likely planet spatial frequency, resulting in planet signal enhancement and isolation. OCIS codes: 110.3080, 110.4280, 350.4600, 120.3180, 120.4570.

An analytical expression is derived for the tilt introduced into a wave front by a Dove prism with manufacturing errors in the prism's base angles and pyramidal angle. We found that the tilt decreases when the base angles are increased above the values of traditional design. The increase in the length-aperture ratio of a prism is detrimental to the prism's performance. However, a Dove prism with a widened aperture increases throughput and maintains a manageable prism weight for implementation in a rotational shearing interferometer. Thus we propose a Dove prism designed with a widened aperture to increase throughput in a rotational shearing interferometer and with larger base angles to minimize the wave-front tilt introduced by manufacturing errors. Experimental results implemented in a rotational shearing interferometer demonstrate the feasibility of this design. OCIS codes: 230.5480, 080.2740, 350.4600, 120.3180, 120.4570.

We analyze and predict the performance of a fiber-optic temperature sensor from the measured fluorescence spectrum to optimize its design. We apply this analysis to an erbium-doped silica fiber by employing the power-ratio technique. We develop expressions for the signal-to-noise ratio in a band to optimize sensor performance in each spectral channel. We improve the signal-to-noise ratio by a factor of 5 for each channel, compared with earlier results. We evaluate the analytical expression for the sensor sensitivity and predict it to be approximately 0.02 [degrees][C.sup.-1] for the temperature interval from room temperature to above 200 [degrees]C, increasing from 0.01 [degrees][C.sup.-1] at the edges of the interval to 0.03 [degrees][C.sup.-1] at the center, at 100-130 [degrees]C. The sensitivity again increases at temperatures higher than 300 [degrees]C, delineating its useful temperature intervals. OCIS codes: 120.5630, 120.6780, 060.2370, 060.2410, 300.2530.

We analyze the imaging performance of a number of diluted-aperture configurations, using the modulation transfer function. We select a single figure of merit, the practical cutoff frequency, rather than the traditional cutoff frequency, as the more useful frequency for the detection of details. Using this new parameter, we compare the performance of a number of published aperture configurations. On the basis of this analysis a new configuration is proposed for the Polar Stratospheric Telescope primary.

The vectorial shearing interferometer is based on the Mach-Zehnder configuration; it incorporates a displacement shearing system composed of a pair of wedge prisms that modify the optical path difference and the tilt of the sheared wave front with respect to that of the reference wave front. Variable shear and tilt can be implemented along any direction by choice of displacements [Delta]x and [Delta]y. The number of fringes and their orientation can be controlled with the vectorial shear. Knowledge of the prescribed displacements in the x and the y directions permits one to obtain a phase gradient in any direction. [C] 2000 Optical Society of America OCIS codes: 220.1000, 220.4840, 220.4830, 120.3180, 120.4820.

The sensitivity analysis indicates that the effective absorption coefficient is most sensitive to the concentration of oxygenated hemoglobin in spectral bands centered at 700 and 960 nm. We find that the highest temporal modulation due to heart function for a thick sample, like an arm, is at 940 nm, a significant shift from 710 nm measured for a finger. The most favorable spectral region for a thick transmission sample, such as a forearm, is the domain defined by intervals [900 nm = ≤ γ 1 ≤ 1000 nm and 650 nm ≤ γ 2 ≤ 720 nm]. We evaluated five near-infrared light-emitting diodes (LEDs) for their potential applications in oximetry. The LED with peak emission at 930 nm emits well in this spectral region. Here the temporal noise is low, and the effective absorption coefficient is strongly dependent on the concentration of the oxygenated hemoglobin. High-quality saturation results are obtained through the forearm during a short measurement (30 s). [ABSTRACT FROM AUTHOR]