730 research outputs found
Familial Micronodular Adrenocortical Disease, Cushing Syndrome, and Mutations of the Gene Encoding Phosphodiesterase 11A4 ( PDE11A)
We present the pathologic findings in the adrenal glands of 4 patients, aged 10 to 38 years, with Cushing syndrome and germline inactivating mutations of the gene PDE11A4 that encodes phosphodiesterase11A4. The gene is expressed in the adrenal cortex and catalyses the hydrolysis of cyclic adenosine monophosphate and cyclic guanosine monophosphate. Two of the patients were mother and daughter; the third had no affected relative; the fourth patient inherited the mutation from her father. Three of the group, including the mother and daughter, had the same pathology, primary pigmented nodular adrenocortical disease, a disorder known to be caused by inactivating mutations of the PRKAR1A gene. In these cases, the adrenal glands were small and the pathologic change was deep in the cortex in which numerous pigmented micronodules developed. In the remaining patient, the glands were slightly enlarged primarily owing to a diffuse hyperplasia of the superficial cortex that extended into the epi-adrenal fat
Accelerator performance analysis of the Fermilab Muon Campus
Fermilab is dedicated to hosting world-class experiments in search of new
physics that will operate in the coming years. The Muon g-2 Experiment is one
such experiment that will determine with unprecedented precision the muon
anomalous magnetic moment, which offers an important test of the Standard
Model. We describe in this study the accelerator facility that will deliver a
muon beam to this experiment. We first present the lattice design that allows
for efficient capture, transport, and delivery of polarized muon beams. We then
numerically examine its performance by simulating pion production in the
target, muon collection by the downstream beam line optics, as well as
transport of muon polarization. We finally establish the conditions required
for the safe removal of unwanted secondary particles that minimizes
contamination of the final beam.Comment: 10 p
Dynamics of ripple formation on silicon surfaces by ultrashort laser pulses in sub-ablation conditions
An investigation of ultrashort pulsed laser induced surface modification due
to conditions that result in a superheated melted liquid layer and material
evaporation are considered. To describe the surface modification occurring
after cooling and resolidification of the melted layer and understand the
underlying physical fundamental mechanisms, a unified model is presented to
account for crater and subwavelength ripple formation based on a synergy of
electron excitation and capillary waves solidification. The proposed
theoretical framework aims to address the laser-material interaction in
sub-ablation conditions and thus minimal mass removal in combination with a
hydrodynamics-based scenario of the crater creation and ripple formation
following surface irradiation with single and multiple pulses, respectively.
The development of the periodic structures is attributed to the interference of
the incident wave with a surface plasmon wave. Details of the surface
morphology attained are elaborated as a function of the imposed conditions and
results are tested against experimental data
Primary pigmented nodular adrenocortical disease presenting with a unilateral adrenocortical nodule treated with bilateral laparoscopic adrenalectomy: a case report
<p>Abstract</p> <p>Introduction</p> <p>Primary pigmented nodular adrenocortical disease is a rare cause of adrenocorticotropic hormone-independent Cushing's syndrome. We report an uncommon primary pigmented nodular adrenocortical disease case presenting with a unilateral adrenocortical nodule and provide a brief overview of the existing literature.</p> <p>Case presentation</p> <p>A 27-year-old Caucasian woman was admitted to our Department with adrenocorticotropic hormone-independent Cushing's syndrome. Its cause was initially considered a left adrenocortical adenoma based on computer tomography imaging. The patient underwent left laparoscopic adrenalectomy and histological examination revealed pigmented micronodular adrenal hyperplasia. Evaluation for the presence of Carney complex was negative. Six months later recurrence of hypercortisolism was documented and a right laparoscopic adrenalectomy was performed further establishing the diagnosis of primary pigmented nodular adrenocortical disease. After a nine-year follow-up there is no evidence of residual disease.</p> <p>Conclusions</p> <p>Even though primary pigmented nodular adrenocortical disease is a rare cause of Cushing's syndrome, it should be included in the differential diagnosis of adrenocorticotropic hormone-independent Cushing's syndrome, especially because adrenal imaging can be misleading mimicking other adrenocortical diseases. Bilateral laparoscopic adrenalectomy is the preferred treatment in these subjects.</p
Post-melting encapsulation of glass microwires for multipath light waveguiding within phosphate glasses
Glass waveguides remain the fundamental component of advanced photonic
circuits and with a significant role in other applications such as quantum
information processing, light generation, imaging, data storage, and sensing
platforms. Up to date, the fabrication of glass waveguides relies mainly on
demanding chemical processes or on the employment of expensive ultrafast laser
equipment. In this work, we demonstrate the feasibility of a simple,
low-temperature, post-melting encapsulation procedure for the development of
advanced glass waveguides. Namely, silver iodide phosphate glass microwires
(MWs) are drawn from typical splat-quenched samples. Following this, the MWs
are incorporated in a controlled manner within previously prepared transparent
silver phosphate glass rectangular prisms. The composition of the employed
glasses is chosen so that the host phosphate glass has a lower refractive index
than the embedded MWs. In such case, the waveguide mechanism relies on the
propagation of light inside the encapsulated higher refractive index MWs.
Moreover, the presence of silver nanoparticles within the MWs enhances the
light transmission due to scattering effects. Waveguide devices with either one
or two incorporated MWs were fabricated. Remarkably, in the latter case, the
transmission of light of different colors and in multipath direction is
possible, rendering the developed waveguides outstanding candidates for various
photonic circuits, optoelectronic, and smart sign glass applications
End-to-end beam simulations for the new muon G-2 experiment at Fermilab
The aim of the new muon g-2 experiment at Fermilab is to measure the anomalous magnetic moment of the muon with an unprecedented uncertainty of 140 ppb. A beam of positive muons required for the experiment is created by pion decay. Detailed studies of the beam dynamics and spin polarization of the muons are important to predict systematic uncertainties in the experiment. In this paper, we present the results of beam simulations and spin tracking from the pion production target to the muon storage ring. The end-to-end beam simulations are developed in Bmad and include the processes of particle decay, collimation (with accurate representation of all apertures) and spin tracking
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