904 research outputs found
THE SCATTERING OF POSITRONS BY ATOMIC HYDROGEN: FORMULATION
The derivation of the coupled systems of second-order integrodifferential equations which must be solved numerically in order to obtain the cross sections for the elastic and inelastic scattering of positrons by atomic hydrogen and the cross sections for the formation of positronium into the 1s and 2s states is considered. The numerical method to be used to solve the equations at incident energies above excitation thresholds is also discussed. (auth
Generating intravital super-resolution movies with conventional microscopy reveals actin dynamics that construct pioneer axons
Super-resolution microscopy is broadening our in-depth understanding of cellular structure. However, super-resolution approaches are limited, for numerous reasons, from utilization in longer-term intravital imaging. We devised a combinatorial imaging technique that combines deconvolution with stepwise optical saturation microscopy (DeSOS) to circumvent this issue and image cells in their native physiological environment. Other than a traditional confocal or two-photon microscope, this approach requires no additional hardware. Here, we provide an open-access application to obtain DeSOS images from conventional microscope images obtained at low excitation powers. We show that DeSOS can be used in time-lapse imaging to generate super-resolution movies in zebrafish. DeSOS was also validated in live mice. These movies uncover that actin structures dynamically remodel to produce a single pioneer axon in a 'top-down' scaffolding event. Further, we identify an F-actin population - stable base clusters - that orchestrate that scaffolding event. We then identify that activation of Rac1 in pioneer axons destabilizes stable base clusters and disrupts pioneer axon formation. The ease of acquisition and processing with this approach provides a universal technique for biologists to answer questions in living animals
Long-term outcome data from 121 patients treated with Gamma Knife stereotactic radiosurgery as salvage therapy for focally recurrent high-grade gliomas.
Introduction: We examined patient outcomes after Gamma Knife stereotactic radiosurgery (GKSRS) salvage therapy for recurrent high-grade gliomas (HGGs) to determine whether tumor grade or lesion size affected overall survival (OS) and progression-free survival (PFS).
Methods: This single-center retrospective study assessed radiographic response and clinical outcomes following GKSRS salvage treatment of recurrent malignant gliomas (January 2005-March 2014).
Results: A total of 121 patients (67 female) with 132 tumors were treated. Median (range) PFS was 4.7 (3.9-5.4) months for the cohort, 6.8 (4.6-8.9) months for initial grade 2 tumors, 4.2 (1.9-6.5) months for initial grade 3 tumors, and 4.3 (3.7-4.9) months for initial grade 4 tumors. Patients with small lesions (≤6.7 cm
Conclusions: GKSRS offers meaningful salvage therapy with minimal morbidity in appropriately selected patients with focally recurrent HGGs
MicroRNA Function in Human Diseases
MicroRNAs are emerging as a hot topic in research, and rightfully so. They show great promise as targets of treatment and as markers for common human diseases, such as cancer and metabolic diseases. In this review, we address some of the basic questions regarding micro- RNA function in human disease and the clinical significance of microRNAs. Specifically, micro- RNAs in epigenetics, cancer, and metabolic diseases are discussed, with examples taken from cholangiocarcinoma and nonalcoholic fatty liver disease
MicroRNA Function in Human Diseases
MicroRNAs are emerging as a hot topic in research, and rightfully so. They show great promise as targets of treatment and as markers for common human diseases, such as cancer and metabolic diseases. In this review, we address some of the basic questions regarding micro- RNA function in human disease and the clinical significance of microRNAs. Specifically, micro- RNAs in epigenetics, cancer, and metabolic diseases are discussed, with examples taken from cholangiocarcinoma and nonalcoholic fatty liver disease
Observation of Quantum Effects in sub Kelvin Cold Reactions
There has been a long-standing quest to observe chemical reactions at low
temperatures where reaction rates and pathways are governed by quantum
mechanical effects. So far this field of Quantum Chemistry has been dominated
by theory. The difficulty has been to realize in the laboratory low enough
collisional velocities between neutral reactants, so that the quantum wave
nature could be observed. We report here the first realization of merged
neutral supersonic beams, and the observation of clear quantum effects in the
resulting reactions. We observe orbiting resonances in the Penning ionization
reaction of argon and molecular hydrogen with metastable helium leading to a
sharp increase in the absolute reaction rate in the energy range corresponding
to a few degrees kelvin down to 10 mK. Our method is widely applicable to many
canonical chemical reactions, and will enable a breakthrough in the
experimental study of Quantum Chemistry
Use of Complete-feed Diets RAMP™ and Test Starter for Receiving Cattle
Performance of newly arrived 576 lb steer calves, fed two complete feeds or a control ration was evaluated. Treatment diets were fed for 30 or 31 days and includeda control receiving diet consisting of alfalfa hay, Sweet Bran® , dry-rolled corn, and supplement or one of two complete feeds: RAMP and Test Starter which contained a high level of Sweet Bran and a minimal amount of forage. RAMP increased ADG when compared with the control diet. Cattle fed Test Starter had similar performance to the control receiving diet
High-speed, long-term, 4D in vivo lifetime imaging in intact and injured zebrafish and mouse brains by instant FLIM
Traditional fluorescence microscopy is blind to molecular microenvironment information that is present in the emission decay lifetime. With fluorescence lifetime imaging microscopy (FLIM), physiological parameters such as pH, refractive index, ion concentration, dissolved gas concentration, and fluorescence resonance energy transfer (FRET) can be measured. Despite these benefits, existing FLIM techniques are typically slow, noisy, and hard to implement due to expensive instrumentation and complex post-processing. To overcome these limitations, we present instant FLIM, a method that allows real-time acquisition and display of two-photon intensity, lifetime, and phasor imaging data. Using analog signal processing, we demonstrate in vivo four-dimensional (4D) FLIM movies by imaging mouse and zebrafish glial cell response to injury over 12 hours through intact skulls. Instant FLIM can be implemented as an upgrade to an existing multiphoton microscope using cost-effective off-the-shelf components, requires no data post-processing, and is demonstrated to be compatible with FD-FLIM super-resolution techniques
Concert recording 2021-11-15
[Track 1] Growth / Cole Powledge -- [Track 2] Day tripper ; Lady Madonna / Lennon/McCartney ; arranged by Tommy Emmanuel -- [Track 3] Disappear / Joshua Larson -- [Track 4] Sirabhorn / Pat Metheny -- [Track 5] Parisienne walkways / Gary Moore -- [Track 6] Songbird / Kenny G -- [Track 7] Drifting / Cody Lucas -- [Track 8] Slow dancing in a burning room / John Mayer -- [Track 9] Suites of morning
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