photons

..In this exciting era of transitioning from in vitro to in vivo and in situ conditions, it is anticipated that SM fluorescence methodology will become a common tool of molecular biology...

..Both photon-based and electron-based imaging methods will ultimately need highly automated data analysis, because the manual tracing of most networks of interest would require hundreds to tens of thousands of years in human labor...

..Two-photon excitation of fluorophores results from the simultaneous absorption of two photons. This excitation process has a number of unique advantages, such as reduced specimen photodamage and enhanced ..

To provide a comparison between radiotherapy with photons, protons and carbon-ions in the treatment of Non-Small-Cell Lung Cancer (NSCLC), performing a meta-analysis of observational studies.

..To investigate the visual outcomes of patients with advanced sinonasal malignancies treated with proton/photon accelerated fractionated radiation (AFR)...

..To image the trabecular meshwork (TM) in its native unfixed state using a non-invasive, non-destructive technique...

..035 g cm(-3)), enhanced for the most energetic beam. For denser, and more clinical, densities a better agreement among the sophisticated algorithms with respect to MC was observed...

..The achieved imaging depth approaches the theoretical limit set by excitation of out-of-focus fluorescence...

..Additional tests were carried out for enhanced dynamic wedges with results comparable to previous results. The basic dosimetric validation of the AAA was therefore considered satisfactory...

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..We compared dosimetry of proton (PR), intensity modulated radiation therapy (IMRT) photon (PH), and combined PR and IMRT PH (PP) irradiation of skull base chordomas to determine the most optimal technique...

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..The precision of localization scales as the inverse square root of the number of photons in the spot for the shot noise limited case and as the inverse of the number of photons for the background noise ..

..Particle therapy has potentially a better therapeutic ratio than photon therapy. However, investment costs are much higher. This study provides an estimation and comparison of the costs of these therapies...

..The aim of this treatment planning study was to investigate the potential advantages of intensity-modulated (IM) proton therapy (IMPT) compared with IM photon therapy (IMRT) in nasopharyngeal carcinoma (NPC)...

..Furthermore, we experimentally demonstrate that there is a one-to-one correlation between achieving strange weak values and violating the Leggett-Garg inequality...

..The data are corrected for the variations of the pulse duration and the beam profile with the excitation wavelength, and are applicable as reference standards for 2PA measurements...

..However, the use of intensity modulated protons provided the only method by which critical structures could be spared at all dose levels, whilst simultaneously providing acceptable dose homogeneity within the target volume...

..VMC + + can be used for photon beam MC patient dose computations without a clinically significant loss in accuracy...

..From the analysis of experimental results, it is concluded that, in principle, an operating limit of 92 MPa in pressure could be achieved with 0.0003% of full scale resolution...

..To investigate the potential of a novel deterministic solver, Attila, for external photon beam radiotherapy dose calculations...

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..The presented method was found to be accurate in a wide range of conditions making it suitable for clinical planning purposes...

..Additionally, since Acuros calculation times are only weakly dependent on the number of beams, Acuros may ideally be suited to arc therapies, where current clinical algorithms may incur long calculation times...

..The basic validation of the Acuros XB algorithm was therefore considered satisfactory for both conventional photon beams as well as for FFF beams of new generation linacs such as the Varian TrueBeam...

..Thus, our results demonstrate the suitability of this technique for real-time analyses of intact neuronal circuits with the resolution of individual cells...

..Particular progress was made with respect to the penumbra and low dose regions. In heterogeneous materials, improvements are substantial and more pronounced for high (18 MV) than for low (6 MV) energies...

To compare retrospectively radiotherapy with neutrons, photons, and a photon/neutron mixed beam in patients with advanced adenoid cystic carcinoma of the head and neck...

..This review illustrates these principles, using as an example action potential recording with optical voltage reporters...

..To evaluate efficacy and tolerance of external fractionated combination of photon and proton radiation therapy (RT) for intracranial benign meningiomas...

..Using highly sensitive cameras, it is now possible to remotely image spontaneous luminescence with a good spatial resolution, providing a new non-invasive tool for mapping oxidative stress and lipid peroxidation in plants...

..The determination of gamma throughout the measured dose distribution provides a presentation that quantitatively indicates the calculation accuracy. Examples of a 6 MV beam penumbra are used to illustrate the gamma index...

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..The developed procedure is applicable to a wide range of accelerators, and has an acceptable accuracy and processing time...

..The hypothesis is that proton radiotherapy decreases the dose and the volume of irradiated normal tissues even when escalating to the maximum tolerable dose of one or more of the organs at risk (OAR)...

..The dissection of the various signal components in bulk-loaded tissue as demonstrated here will enable further studies of signal flow through cortical networks...

To compare advanced treatment techniques with photons and protons as a stereotactic body radiation therapy (SBRT) for adrenal glands metastases.

..The measured system detection efficiency at 1556 nm is 95 % +/- 2 %, which to our knowledge is the highest system detection efficiency reported for a near-infrared single-photon detector...

..To investigate the feasibility and potential benefits of combining electron and photon intensity modulated radiotherapy (IMRT) for patients with malignant pleural mesothelioma (MPM)...

..Furthermore, we discuss labeling strategies, acquisition parameters, and temporal and spatial resolution. The ultimate step of data acquisition and data processing can be performed in seconds to minutes...

..2PFM was used to demonstrate lysosomal tracking with LT1...

..To synthesize and compare available evidence considering the effectiveness of carbon-ion, proton and photon radiotherapy for head and neck cancer...

..work provides a review of the recently published data and the knowledge of the RBE of low energy electrons and photons. The review presents RBE values derived from experimental data and model calculations including cell inactivation,..

..By counting the number of photons emitted from a specimen, BLI can quantify biological events such as tumour growth, gene expression and drug ..

We report the design of a single-molecule nanomotor driven by photons. The nanomotor is a DNA hairpin-structured molecule incorporated with azobenzene moieties to facilitate reversible photocontrollable switching...

..Pre-computed energy spectra for 60Co to 24 MV are used to compute the dose ratios for these photon beams and to determine an effective energy for evaluation of the dose ratio...

..To image the conventional aqueous outflow pathway and adjacent structures within the intact enucleated mouse eye using a noninvasive microscopy technique...

..This process is both of fundamental interest and relevant for applications in future ultra-efficient photovoltaic devices...

..This study reveals the involvement of ROS generation in biophoton emission in the process of HR through the determination of the inhibitory effect of an antioxidant (Tiron) on biophoton emission...

..Recent work has begun to achieve this goal through a combination of modern imaging methods with genetic labeling and perturbation...

Since scattered photons carry degraded spatial information, scatter is typically considered a source of contamination in SPECT...

..for the induction of single-strand breaks (SSB) and double-strand breaks (DSB) in plasmid DNA by low-energy photons and provide estimates for the energy dependence of strand-break formation important for track-structure ..

..This approach offers the needed ability to concurrently image multiple colored, spectrally overlapping marker proteins within living cells...

..The ability to monitor biophoton emission from whole plants in real time should allow detailed dissection of plant defence responses...

..The ability to assay R responses nondestructively in real time and a chosen genetic background makes this technique amenable to subtle genetic dissection of plant defense responses...

..are useful for studying SPECT imaging, this study investigates the MC simulation of 90Y bremsstrahlung photons in SPECT...

..We investigated antidepressant responses to light using two light-emitting diode (LED) sources, each emitting substantial short-wavelength light, but <2500 lux...

..These observations provide direct evidence that singlet oxygen is involved in biophoton emission from radish root cells...

..Quantitative (124)I PET imaging is challenging as (124)I has a complex decay scheme. In this study the performance of a Philips Gemini dual GS PET/CT system was optimized and assessed for (124)I...

..Imaging is based on a complete-angle projection tomographic technique that utilizes transmitted early photons. Results are contrasted with measurements obtained at later gates as well as pseudocontinuous-wave data...

..A comparison was made for a conventional low photon energy (6 MV) and 50 MV photons for the treatment of a lung tumour...

..Measured coincidences between annihilation photons and this cascade gamma radiation are essentially true coincidences and the standard PET corrections do not ..

..g. DIBH) are assumed for treatment. In contrast, CC and AAA manifested a high degree of consistency against the Monte Carlo method and provided stable results over the entire range of clinically relevant densities...

..To describe the preliminary results after intraoperative radiotherapy (IORT) with the photon radiosurgery system in children with recurrent brain tumors treated at the first dose level (10 Gy) of a Phase I protocol...

..Our simulations capture the major features of the data with the theoretical framework developed in our group to separately calculate the response functions and population dynamics...

..However, the late effects of photon radiation compromise function and cosmetic outcome. Proton radiation can provide excellent tumor dose distributions while sparing normal tissues better than photon irradiation...

..The multicolor multiphoton microscope is suitable for highly sensitive, real-time, spectrally-resolved three-dimensional imaging in biomedical applications...

..We conclude that PRS IR is effective in the treatment of metastases while it provides lower benefit in malignant gliomas. It could play a major role in low-grade astrocytomas...

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..In addition, the application of the MC method for dose calculations in radiotherapy with 60Co photons was recommended.

..were also measured using nearly monoenergetic X-ray beams which were designed to simulate the mean energies of photons emitted by 125I and 103Pd and also using a clinical 250 kVp X-ray beam...

..The same trend brings us closer to understanding how defects in photoreceptor signaling can lead to cell death and retinal degeneration...

..We successfully resolved this mixture of fusion proteins with a single dual-color PCH measurement. These results highlight the potential of dual-color PCH to directly detect and quantify protein mixtures in living cells...

..The treatment planning comparison was extended by varying the number of fields to study its effect on the performance of each modality. Risks of secondary cancer induction were also calculated for all modalities...

..Protons have superior dose distributional qualities compared to photons, as dose deposition occurs in a modulated narrow zone, called the Bragg peak...

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..We find that there are two noncascading exciton energy relaxation pathways...

..Finally, a 10% and 20% dose escalation with IM protons was planned, and the consequential organ at risk (OAR) irradiation was evaluated...

..In the current work, we investigated the impact that our method has on the quantitative accuracy of small-animal PET...

..In the future, radiochromic film based commissioning might provide a more accurate data set for dose modeling...

High atomic number (Z) heterogeneities in tissue exposed to photons with energies of up to about 1 MeV can cause significant dose perturbations in their immediate vicinity...

..The ability to visualize when, where, and how tumor cells are killed in vivo offers new perspectives for understanding how immune effectors survey cancer cells and how local tumor microenvironments may subvert immune responses...

..D., and F. Rieke. 2002. Neuron. 35:733-747.), also argue strongly against either feedback (including Ca2+-feedback) or depletion of any molecular species downstream to R* as the dominant cause of SPR reproducibility...

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..This approach represents a tool to analyze point-wise signaling dynamics without requiring averaging over the entire cell by global Michaelis-Menten kinetics...

..Although the clinical value needs further investigations, PRS IR seems to be effective in metastases while it provides less benefit in malignant gliomas. PRS IR could have a major role in the treatment of low-grade astrocytomas...

..TPCLSM images obtained from stained cells indicate preferential RNA staining by Cyan 40 compared with DNA...

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..Two-photon microscopy, in combination with newly developed indicator molecules, promises to extend single-cell approaches to the in vivo setting and to reveal in detail the cellular collaborations that underlie the immune response...

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..The proposed pulse sequences may also be applied to reveal information on the robustness of quantum states in the presence of fluctuating environments in other nanoscopic complexes and devices...

..Antigenic challenge changed T cell trajectories from random walks to "swarms" and stable clusters. Real-time two-photon imaging reveals lymphocyte behaviors that are fundamental to the initiation of the immune response...

..We analyzed outcome after a carbon ion boost in combination with precision photon radiation therapy in patients with meningiomas...

..Determine the radiobiological effectiveness (RBE) for low-energy X-rays (average energy of 23 KeV) produced by the Photon Radiosurgery System (PRS)...

..The data definitively show that the stratum corneum acid mantle results from the presence of aqueous acidic pockets within the lipid-rich extracellular matrix...

..Cell cycle studies have shown that in G1 cells, a significant fraction of multiphoton laser-induced prompt DSBs persists for > 4 h in addition to those induced at replication...

..Thus, we can report the development of DNA probes in the form of photon-controllable (thrombin) inhibitors, termed PCIs, and we expect that this approach will be highly beneficial in future biomedical and pharmaceutical applications...

..In addition, cytotoxicity tests showed that the low-micromolar concentrations of Zn(S)(2)L did not cause significant reduction in cell viability over a period of at least 24 h and should be safe for further biological studies...

..Any light, including both singly and multiply scattered photons, contributes to the imaging signal; as a result, the imaging depth in fPAT is better than in OCT...

..receptors for light (photoreceptors) are the basis of all forms of vision where the energy from absorbed single photons is used to bring about a conformational change in the chromophore, usually the isomerization of a double bond ..

..Any light, including both singly and multiply scattered photons, contributes to the imaging signal; as a result, the imaging depth in fPAT is better than in OCT...

..These technologies take advantage of known non-linear optical affects that occur when high intensity photons generated by ultrafast lasers interact with tissue...

..acquire projection data simultaneously from two or more pharmaceuticals each labeled with a radioisotope emitting photons with different energies, allowing simultaneous measurement of multiple physiological processes such as rest/..

..acquire projection data simultaneously from two or more pharmaceuticals each labeled with a radioisotope emitting photons with different energies, allowing simultaneous measurement of multiple physiological processes such as rest/..

..SPR is collective oscillation of delocalized noble metal electrons polarized by incident resonant photons. It yields absorption cross-sections >106-fold higher than fluorescent dyes, allowing label-free detection of ..

..Arabidopsis contains several photoreceptors that monitor photons at different wavelengths...

..non-consensual sex? 2) When viewed as colposcopic photons, what is the difference in number, type and location of injury to the female genitalia and/or anus after ..

The primary objective is to develop new inorganic scintillators for detecting 511 keV photons with exceptional detection efficiency (similar to BGO), response time (1 ns), and energy resolution (3% fwhm)...

..v.-absorbing chromophores. Uncaging using such lasers is produced by the simultaneous absorption of two red photons of equivalent energy to one blue photon...

..During daylight, a continual rain of photons bleaches visual pigments in photoreceptor cells of our retinas to initiate phototransduction...

When photons of light enter the eye, the retina converts them into an electrical signal through a biochemical process called phototransduction...

When photons of light enter the eye, the retina converts them into an electrical signal through a biochemical process called phototransduction...

When photons of light enter the eye, the retina converts them into an electrical signal through a biochemical process called phototransduction. This signal is then relayed to the visual cortex of the brain, where visual perception occurs...

..Upon activation by photons, 11-cis retinal is photo-isomerized to all-trans retinal, which triggers the activation of the phototransduction ..

..Upon activation by photons, 11-cis retinal is photo-isomerized to all-trans retinal, which triggers the activation of the phototransduction ..

..At each decay event, the electron avalanche produces gaseous scintillation; for argon, approximately 35 photons are produced per keV of beta particle energy with the output centered at 280 nm...

..with structures determined by the local type and activity of steroidogenic system, as well as the access to UVB photons. To test this hypothesis the following specific aims have been designed. 1...

..with structures determined by the local type and activity of steroidogenic system, as well as the access to UVB photons. To test this hypothesis the following specific aims have been designed. 1...

..with structures determined by the local type and activity of steroidogenic system, as well as the access to UVB photons. To test this hypothesis the following specific aims have been designed. 1...

..detection unit will consist of two stacked surface barrier detectors; the first device detects beta particles and photons, while the rear detector only detects photons (due to the shielding effects of the front detector)...

..The difference in the images yields the "polarized image". Such imaging accepts photons backscattered from the subsurface and superficial layers of skin, but rejects surface glare and deeply ..

..Solid organic scintillators convert energy absorbed from ionizing radiation fields into blue fluorescent photons, creating a measurable optical signal related to absorbed dose in the surrounding medium...

..high- speed time-gated photon counting detection of the earliest-transmitted and therefore least scattered photons through animals, thereby allowing imaging resolution approaching 250 5m without loss of sensitivity or accuracy, ..

..100 femtosecond) pulses generated by mode-locked lasers allow simultaneous absorption of two or more photons from bright pulsed illumination for molecular excitation as in the multiphoton laser scanning fluorescence ..

..In our approach, we propose to implement a novel technology where the incoming x-ray photons are energy-separated...

..Both of the technologies depend primarily on singly backscattered photons for spatial resolution...

One unique feature of SPECT is the ability to use two pharmaceuticals labeled with different isotopes emiting photons with different energies to make simultaneous measurements of different physiological processes...

One unique feature of SPECT is the ability to use two pharmaceuticals labeled with different isotopes emitting photons with different energies to make simultaneous measurements of different physiological processes...