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Glucagon Secreting Tumors and Glucagonoma Syndrome
Glucagonomas are the functioning neuroendocrine tumors. These arise from pancreatic islet α-cells. These tumors are extremely rare and have an annual incidence of 1 per 20-40 million population 80% of glucagon-expressing tumors are sporadic, and 20% are associated with genetic syndromes such as Multiple Endocrine Neoplasia-type 1. Glucagonoma typically occurs in the distal pancreas, and around 85% are in the body or tail. It tends to be large at the time of diagnosis. Most reported cases of glucagonoma are malignant and about 65-75% patients present with metastatic disease. The liver is usually the first site of metastases, followed by the involvement of peripancreatic lymph nodes. The term Glucagonoma syndrome and glucagonoma are often interchangeably used, but in fact, these are two distinct entities. Glucagonoma syndrome comprises of necrolytic migratory erythema, hyperglucagonemia, diabetes mellitus, anemia, weight loss, glossitis, diarrhea, venous thrombosis and neuropsychiatric disturbances in the presence of a glucagon-producing tumor of the pancreas. Tumors secreting glucagon can occur without the glucagonoma syndrome. The glucagonoma secretion depends on the expression of protein convertase enzyme PC1/3 or PC2 within the tumor itself. As a result of this expression, the clinical manifestations can be variable. The tumor can either present with hyperinsulinemic hypoglycemia in a patient with a previous history of diabetes or with the features of the glucagonoma syndrome. In cases where a tumor is localized surgery is the curative treatment. Reduction of the tumor bulk, removal of the primary by surgery and targeted therapy for the hepatic metastases are the favored approach even when there is the metastasis
Injection Scheme with Deflecting Cavity for Ultimate Storage Ring
We suggest a new on-axis injection scheme that uses two deflecting cavities
to remove the tilt of the stored beam, and to kick the injected beam into the
ring. In this new injection scheme, an injected beam with a certain angle is
overlaid on the stored beam position in transverse phase space through the
second deflecting cavity. (Note that the injected beam has separated phase with
the stored beam in longitudinal phase space). We present theoretical analysis
and numerical simulations of the stored beam and injected beam with the new
injection scheme
Chromophore Ordering by Confinement into Carbon Nanotubes
International audienceWe report an experimental study on the confinement of oligothiophene derivatives into single-walled carbon nanotubes over a large range of diameter (from 0.68 to 1.93 nm). We evidence by means of Raman spectroscopy and transmission electron microscopy that the supramolecular organizations of the confined oligothiophenes depend on the nanocontainer size. The Raman Radial Breathing Mode frequency is shown to be monitored by both the number of confined molecules into a nanotube section and the competition between oligothiophene/oligothiophene and oligothiophene/tube wall interactions. We finally propose simple Raman criteria to characterize oligothiophene supramolecular organization at the nanoscale
Structure near ++ threshold in the in-flight He reaction
To search for an S= -1 di-baryonic state which decays to , the reaction was studied at 1.0 GeV/.
Unobserved neutrons were kinematically identified from the missing mass
of the reaction in order to have a large
acceptance for the final state. The observed events,
distributed widely over the kinematically allowed region of the Dalitz plot,
establish that the major component comes from a three nucleon absorption
process. A concentration of events at a specific neutron kinetic energy was
observed in a region of low momentum transfer to the . To account
for the observed peak structure, the simplest S-wave pole was assumed to exist
in the reaction channel, having Breit-Wigner form in energy and with a Gaussian
form-factor. A minimum method was applied to deduce its mass
2355 (stat.) (syst.) MeV/c, and decay-width
110 (stat.) (syst.) MeV/c,
respectively. The form factor parameter 400 MeV/ implies that the
range of interaction is about 0.5Comment: 12pages, 8 figure
Using irregularly spaced current peaks to generatean isolated attosecond X-ray pulse in free-electron lasers
A method is proposed to generate an isolated attosecond X-ray pulse in free-electron lasers, using irregularly spaced current peaks induced in an electron beam through interaction with an intense short-pulse optical laser. In comparison with a similar scheme proposed in a previous paper, the irregular arrangement of current peaks significantly improves the contrast between the main and satellite pulses, enhances the attainable peak power and simplifies the accelerator layout. Three different methods are proposed for this purpose and achievable performances are computed under realistic conditions. Numerical simulations carried out with the best configuration show that an isolated 7.7keV X-ray pulse with a peak power of 1.7TW and pulse length of 70as can be generated. In this particular example, the contrast is improved by two orders of magnitude and the peak power is enhanced by a factor of three, when compared with the previous scheme.1152Ysciescopu
Anastomotic leak management after a low anterior resection leading to recurrent abdominal compartment syndrome: a case report and review of the literature
<p>Abstract</p> <p>Introduction</p> <p>Low anterior resection is usually the procedure of choice for rectal cancer, but a series of complications often accompany this procedure. This case report describes successful management of an intricate anastomotic leak after a low anterior resection.</p> <p>Case presentation</p> <p>A 66-year-old Caucasian man was admitted to our hospital and diagnosed with a low rectal adenocarcinoma. He underwent a low anterior resection but subsequently developed fecal peritonitis due to an anastomotic leak. He was operated on again but developed abdominal compartment syndrome, multi-organ failure and sepsis. He was aggressively treated in the intensive care unit and in the operating room. Overall, the patient underwent four laparotomies and stayed in the intensive care unit for 75 days. He was discharged after 3 months of hospitalization.</p> <p>Conclusion</p> <p>Abdominal compartment syndrome may present as a devastating complication of damage control laparotomy. Prompt recognition and goal-directed management are the cornerstones of treatment.</p
A Long Baseline Neutrino Oscillation Experiment Using J-PARC Neutrino Beam and Hyper-Kamiokande
Document submitted to 18th J-PARC PAC meeting in May 2014. 50 pages, 41 figuresDocument submitted to 18th J-PARC PAC meeting in May 2014. 50 pages, 41 figuresDocument submitted to 18th J-PARC PAC meeting in May 2014. 50 pages, 41 figuresHyper-Kamiokande will be a next generation underground water Cherenkov detector with a total (fiducial) mass of 0.99 (0.56) million metric tons, approximately 20 (25) times larger than that of Super-Kamiokande. One of the main goals of Hyper-Kamiokande is the study of asymmetry in the lepton sector using accelerator neutrino and anti-neutrino beams. In this document, the physics potential of a long baseline neutrino experiment using the Hyper-Kamiokande detector and a neutrino beam from the J-PARC proton synchrotron is presented. The analysis has been updated from the previous Letter of Intent [K. Abe et al., arXiv:1109.3262 [hep-ex]], based on the experience gained from the ongoing T2K experiment. With a total exposure of 7.5 MW 10 sec integrated proton beam power (corresponding to protons on target with a 30 GeV proton beam) to a -degree off-axis neutrino beam produced by the J-PARC proton synchrotron, it is expected that the phase can be determined to better than 19 degrees for all possible values of , and violation can be established with a statistical significance of more than () for () of the parameter space
Fermi level shift in carbon nanotubes by dye confinement
International audienceDye confinement into carbon nanotube significantly affects the electronic charge density distribution of the final hybrid system. Using the electron-phonon coupling sensitivity of the Raman G-band, we quantify experimentally how charge transfer from thiophene oligomers to single walled carbon nanotube is modulated by the diameter of the nano-container and its metallic or semiconducting character. This charge transfer is shown to restore the electron-phonon coupling into defected metallic nanotubes. For sub-nanometer diameter tube, an electron transfer optically activated is observed when the excitation energy matches the HOMO-LUMO transition of the confined oligothiophene. This electron doping accounts for an important enhancement of the photoluminescence intensity up to a factor of nearly six for optimal confinement configuration. This electron transfer shifts the Fermi level, acting on the photoluminescence efficiency. Therefore, thiophene oligomer encapsulation allows modulating the electronic structure and then the optical properties of the hybrid system
Charge transfer in conjugated oligomers encapsulated into carbon nanotubes
This study deals with a hybrid system consisting in quaterthiophene derivative encapsulated inside single-walled and multi-walled carbon nanotubes. Investigations of the encapsulation step are performed by transmission electron microscopy. Raman spectroscopy data point out different behaviors depending on the laser excitation energy with respect to the optical absorption of quaterthiophene. At low excitation energy (far from the oligomer resonance window) there is no significant modification of the Raman spectra before and after encapsulation. By contrast, at high excitation energy (close to the oligomer resonance window), Raman spectra exhibit a G-band shift together with an important RBM intensity loss, suggesting a significant charge transfer between the inserted molecule and the host nanotubes. Those results suggest a photo induced process leading to a significant charge transfer.Peer reviewe
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