Effectiveness of elastodontic appliances in the treatment of malocclusions: a review of the literature.

This paper aims to verify the effectiveness of using elastodontic devices in the treatment of malocclusions in growing patients. An English-language literature search was conducted. The following electronic databases were selected for searching from 2020 to June 2023: PubMed, Web of Science, and Scopus.

Efficacy of elastodontic devices in overjet and overbite reduction assessed by computer-aid evaluation.

Background: This study aimed to verify the efficacy of two elastodontic devices in overjet (OJ) and overbite (OB) reduction during treatment with the Equilibrator Series II (Eptamed) and Occlus-o-Guide (Sweden & Martina) devices.

Method: Sixty patients aged 7-15 years were enrolled in the study, and were divided into test and control groups. The test group included 30 patients (14 males, 16 females; mean age, 10.

Single-molecule FRET experiments with a red-enhanced custom technology SPAD.

Single-molecule fluorescence spectroscopy of freely diffusing molecules in solution is a powerful tool used to investigate the properties of individual molecules. Single-Photon Avalanche Diodes (SPADs) are the detectors of choice for these applications. Recently a new type of SPAD detector was introduced, dubbed red-enhanced SPAD (RE-SPAD), with good sensitivity throughout the visible spectrum and with excellent timing performance.

New silicon technologies enable high-performance arrays of Single Photon Avalanche Diodes.

In order to fulfill the requirements of many applications, we recently developed a new technology aimed at combining the advantages of traditional thin and thick silicon Single Photon Avalanche Diodes (SPAD). In particular we demonstrated single-pixel detectors with a remarkable improvement in the Photon Detection Efficiency at the longer wavelengths (e.g.

Development of new photon-counting detectors for single-molecule fluorescence microscopy.

Two optical configurations are commonly used in single-molecule fluorescence microscopy: point-like excitation and detection to study freely diffusing molecules, and wide field illumination and detection to study surface immobilized or slowly diffusing molecules. Both approaches have common features, but also differ in significant aspects. In particular, they use different detectors, which share some requirements but also have major technical differences.

Photonics for life.

Light is strictly connected with life, and its presence is fundamental for any living environment. Thus, many biological mechanisms are related to light interaction or can be evaluated through processes involving energy exchange with photons. Optics has always been a precious tool to evaluate molecular and cellular mechanisms, but the discovery of lasers opened new pathways of interactions of light with biological matter, pushing an impressive development for both therapeutic and diagnostic applications in biomedicine.

New photon-counting detectors for single-molecule fluorescence spectroscopy and imaging.

Solution-based single-molecule fluorescence spectroscopy is a powerful new experimental approach with applications in all fields of natural sciences. Two typical geometries can be used for these experiments: point-like and widefield excitation and detection. In point-like geometries, the basic concept is to excite and collect light from a very small volume (typically femtoliter) and work in a concentration regime resulting in rare burst-like events corresponding to the transit of a single-molecule.

Ultra high-throughput single molecule spectroscopy with a 1024 pixel SPAD.

Single-molecule spectroscopy is a powerful approach to measuring molecular properties such as size, brightness, conformation, and binding constants. Due to the low concentrations in the single-molecule regime, measurements with good statistical accuracy require long acquisition times. Previously we showed a factor of 8 improvement in acquisition speed using a custom-CMOS 8x1 SPAD array.

High-throughput FCS using an LCOS spatial light modulator and an 8 × 1 SPAD array.

We present a novel approach to high-throughput Fluorescence Correlation Spectroscopy (FCS) which enables us to obtain one order of magnitude improvement in acquisition time. Our approach utilizes a liquid crystal on silicon spatial light modulator to generate dynamically adjustable focal spots, and uses an eight-pixel monolithic single-photon avalanche photodiode array. We demonstrate the capabilities of this system by showing FCS of Rhodamine 6G under various viscosities, and by showing that, with proper calibration of each detection channel, one order of magnitude improvement in acquisition speed is obtained.

High-throughput single-molecule fluorescence spectroscopy using parallel detection.

Solution-based single-molecule fluorescence spectroscopy is a powerful new experimental approach with applications in all fields of natural sciences. The basic concept of this technique is to excite and collect light from a very small volume (typically femtoliter) and work in a concentration regime resulting in rare burst-like events corresponding to the transit of a single-molecule. Those events are accumulated over time to achieve proper statistical accuracy.

High-throughput multispot single-molecule spectroscopy.

Solution-based single-molecule spectroscopy and fluorescence correlation spectroscopy (FCS) are powerful techniques to access a variety of molecular properties such as size, brightness, conformation, and binding constants. However, this is limited to low concentrations, which results in long acquisition times in order to achieve good statistical accuracy. Data can be acquired more quickly by using parallelization.

Dual-color microchip electrophoresis with single-photon avalanche diodes: application to mutation detection.

A novel microchip electrophoresis instrument based on single-photon avalanche diodes was used for the molecular characterization of mutations in disease genes. The identification of the main mutation causing cystic fibrosis, named DeltaF508, by the Amplification Refractory Mutation System was used to validate the technology. In our implemented protocol the wild-type and mutant allele-specific primers are labeled with Cy5 and Cy5.

Optical crosstalk in single photon avalanche diode arrays: a new complete model.

One of the main issues of Single Photon Avalanche Diode arrays is optical crosstalk. Since its intensity increases with reducing the distance between devices, this phenomenon limits the density of integration within arrays. In the past optical crosstalk was ascribed essentially to the light propagating from one detector to another through direct optical paths.

Time-resolved diffuse reflectance using small source-detector separation and fast single-photon gating.

We demonstrate the feasibility of time-resolved diffuse reflectance measurements at small source-detector separations using a single-photon avalanche diode operated in time-gated mode. Photon time distributions at an interfiber distance of 2 mm were obtained on a homogeneous tissue phantom with a dynamic range of 10(6) and collecting photons at arrival times up to 4 ns. Moreover, we were able to detect a local inhomogeneity deeply buried within a diffusive medium with better spatial resolution, higher signal intensity, and same contrast of a larger (20 mm) interfiber distance.

Time-of-Flight Optical Ranging System Based on Time-Correlated Single-Photon Counting.

The design and implementation of a prototype time-of-flight optical ranging system based on the time-correlated single-photon-counting technique are described. The sensor is characterized in terms of its longitudinal and transverse spatial resolution, single-point measurement time, and long-term stability. The system has been operated at stand-off distances of 0.

Self-suppression of reset induced triggering in picosecond SPAD timing circuits.

We present a new photon timing circuit that achieves a time resolution of 35 ps full width at half maximum with single photon avalanche diodes having active area diameters up to 200 microm. The timing circuit is based on a double avalanche current sensing network that makes it particularly suited to operation at high photon counting rates. Thanks to its self-adjusting capabilities, no trimming is needed even when changing the photodetector operating conditions over a wide range.

Operation of silicon single photon avalanche diodes at cryogenic temperature.

This article reports a complete characterization of single photon avalanche diodes (SPADs) at temperatures down to 120 K. We show that deep cooling of the device by means of a compact liquid-nitrogen Dewar brings several advantages, such as extremely low dark counting rates (down to 1 counts/s), better time resolution, and higher quantum efficiency in the visible range. By using a special current pick-off circuit, we achieved a time resolution of 20 ps full width at half maximum at 120 K for a 50 mum diameter SPAD.

Enhanced performance photon-counting time-of-flight sensor.

We describe improvements to a time-of-flight sensor utilising the time-correlated single-photon counting technique employing a commercially-available silicon-based photon-counting module. By making modifications to the single-photon detection circuitry and the data analysis techniques, we experimentally demonstrate improved resolution between multiple scattering surfaces with a minimum resolvable separation of 1.7 cm at ranges in excess of several hundred metres.

Microchips and single-photon avalanche diodes for DNA separation with high sensitivity.

Modern techniques for DNA and protein analysis and separation rely on measurements of LIF and face a trend toward employing progressively smaller samples. The currently employed detectors that provide the required ultrahigh sensitivity, e.g.

Monolithic active quenching and picosecond timing circuit suitable for large-area single-photon avalanche diodes.

A new integrated active quenching circuit (i-AQC) designed in a standard CMOS process is presented, capable of operating with any available single photon avalanche diode (SPAD) over wide temperature range. The circuit is suitable for attaining high photon timing resolution also with wide-area SPADs. The new i-AQC integrates the basic active-quenching loop, a patented low-side timing circuit comprising a fast pulse pick-up scheme that substantially improves time-jitter performance, and a novel active-load passive quenching mechanism (consisting of a current mirror rather than a traditional high-value resistor) greatly improves the maximum counting rate.

Single-photon imaging at 20,000 frames/s.

A complete two-dimensional imaging system based on a silicon monolithic array of 60 single-photon counters is presented. The fabricated solid-state array is rugged and operates at low voltages. Detection efficiency is higher than 40% in the visible range, and cross talk among 50 microm pixels is lower than 10(-4).

Complete single-photon counting and timing module in a microchip.

A complete module for single-photon counting and timing is demonstrated in a single chip. Features comparable with or better than commercially available macroscopic modules are obtained by integration of an active-quenching and active-reset circuit in complementary metal-oxide semiconductor technology together with a single-photon avalanche diode (SPAD). The integrated SPAD has a 12-microm-diameter sensitive area and operates with an overvoltage above breakdown adjustable up to 20 V.

Quantum key distribution system clocked at 2 GHz.

An improved quantum key distribution test system operating at clock rates of up to 2GHz using a specially adapted commercially-available silicon single-photon counting module is presented. The use of an enhanced detector has improved the fiber-based quantum key distribution test system performance in terms of transmission distance and quantum bit error rate.

Use of high-molecular-mass polyacrylamides as matrices for microchip electrophoresis of DNA fragments.

DNA fragment analysis requires the use of polymer solutions as sieving matrices. Generally, such matrices are constituted of high-molar-weight polymers employed at a concentration higher than their entanglement threshold concentration. These polymer solutions are highly viscous and difficult to use in the narrow channels of a microchip.

Protein conformational dynamics probed by single-molecule electron transfer.

Electron transfer is used as a probe for angstrom-scale structural changes in single protein molecules. In a flavin reductase, the fluorescence of flavin is quenched by a nearby tyrosine residue by means of photo-induced electron transfer. By probing the fluorescence lifetime of the single flavin on a photon-by-photon basis, we were able to observe the variation of flavin-tyrosine distance over time.