126 research outputs found
Imaging of urgencies and emergencies in the lung cancer patient
Lung cancer patients often experience potentially life-threatening medical urgencies and emergencies, which may be a direct or indirect result of the underlying malignancy. This pictorial review addresses the most common thoracic, neurological and musculoskeletal medical emergencies in lung cancer patients, including superior vena cava syndrome, pulmonary embolism, spontaneous pneumothorax, cardiac tamponade, massive haemoptysis, central airway obstruction, oesophagorespiratory fistula, malignant spinal cord compression, carcinomatous meningitis, cerebral herniation and pathological fracture. Emphasis is placed on imaging findings, the role of different imaging techniques and a brief discussion of epidemiology, pathophysiology and therapeutic options. Since early diagnosis is important for adequate patient management and prognosis, radiologists have a crucial role in recognising and communicating these urgencies and emergencies. Teaching points Multiplanar multidetector computed tomography is the imaging examination of choice for thoracic urgencies and emergencies. Magnetic resonance imaging is the imaging modality of choice for investigating central nervous system emergencies. Urgencies and emergencies can be the initial manifestation of lung cancer. Radiologists have a crucial role in recognising and in communicating these urgencies/emergencies
The Sariçiçek Howardite Fall in Turkey: Source Crater of HED Meteorites on Vesta and İmpact Risk of Vestoids
The Sariçiçek howardite meteorite shower consisting of 343 documented stones
occurred on 2 September 2015 in Turkey and is the first documented howardite fall. Cosmogenic
isotopes show that Sariçiçek experienced a complex cosmic ray exposure history, exposed during
~12–14 Ma in a regolith near the surface of a parent asteroid, and that an ~1 m sized meteoroid
was launched by an impact 22 ± 2 Ma ago to Earth (as did one third of all HED meteorites). SIMS
dating of zircon and baddeleyite yielded 4550.4 ± 2.5 Ma and 4553 ± 8.8 Ma crystallization ages
for the basaltic magma clasts. The apatite U-Pb age of 4525 ± 17 Ma, K-Ar age of ~3.9 Ga, and
the U,Th-He ages of 1.8 ± 0.7 and 2.6 ± 0.3 Ga are interpreted to represent thermal metamorphic
and impact-related resetting ages, respectively. Petrographic, geochemical and O-, Cr- and Tiisotopic
studies confirm that Sariçiçek belongs to the normal clan of HED meteorites. Petrographic
observations and analysis of organic material indicate a small portion of carbonaceous chondrite
material in the Sariçiçek regolith and organic contamination of the meteorite after a few days on
soil. Video observations of the fall show an atmospheric entry at 17.3 ± 0.8 kms-1 from NW,
fragmentations at 37, 33, 31 and 27 km altitude, and provide a pre-atmospheric orbit that is the
first dynamical link between the normal HED meteorite clan and the inner Main Belt. Spectral data
indicate the similarity of Sariçiçek with the Vesta asteroid family (V-class) spectra, a group of
asteroids stretching to delivery resonances, which includes (4) Vesta. Dynamical modeling of
meteoroid delivery to Earth shows that the complete disruption of a ~1 km sized Vesta family
asteroid or a ~10 km sized impact crater on Vesta is required to provide sufficient meteoroids ≤4
m in size to account for the influx of meteorites from this HED clan. The 16.7 km diameter Antonia
impact crater on Vesta was formed on terrain of the same age as given by the 4He retention age of
Sariçiçek. Lunar scaling for crater production to crater counts of its ejecta blanket show it was
formed ~22 Ma ago
Dipolar Characteristics of the Imine-group and its Hydrogen-bonds - a Quantum-chemical and Experimental Approach
The dipole moments of two aliphatic imines and their hydrogen bonded phenol complexes were determined experimentally. A value of 1.63 D was found for isopropyl, N isopropyl imine and 1.60 D for tertio butyl, N isobutyl imine. Their complexes with phenol, 3,5 dichloro- and para nitro phenol are respectively of 3.45, 4.57 and 6.99 D for the first and 3.69, 4.67 and 7.10 D for the second. This experimental study was completed by a theoretical study of model imines and their complexes with watermethanol and formic acid. The theoretical results explain through structural and electronic arguments the variation of the dipole moments. They furnish also values of the angles which are indispensable for the discussion of experimental dipole increments. The dipole increments obtained show clearly the strength of the H-bond obtained with imine bases as well as its sensibility to the strength of the associated acid
Fourier transform infrared and theoretical study of alkylimines complexed with hydroxylic proton donors
Fourier transform infrared and theoretical study of alkylimines complexed with hydroxylic proton donor
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