Absorption in Ultra-Peripheral Nucleus-Atom Collisions in Crystal

The Glauber theory description of particle- and nucleus-crystal Coulomb interactions at high-energy is developed. The allowance for the lattice thermal vibrations is shown to produce strong absorption effect which is of prime importance for quantitative understanding of the coherent Coulomb excitation of ultra-relativistic particles and nuclei passing through the crystal.Comment: 8 pages, LaTe

Limit on Lorentz and CPT violation of the bound Neutron Using a Free Precession 3He/129Xe co-magnetometer

We report on the search for Lorentz violating sidereal variations of the frequency difference of co-located spin-species while the Earth and hence the laboratory reference frame rotates with respect to a relic background field. The co-magnetometer used is based on the detection of freely precessing nuclear spins from polarized 3He and 129Xe gas samples using SQUIDs as low-noise magnetic flux detectors. As result we can determine the limit for the equatorial component of the background field interacting with the spin of the bound neutron to be bn < 3.7 x 10^{-32} GeV (95 C.L.).Comment: 5 pages, 4 figure

Characterisation of urban environment and activity across space and time using street images and deep learning in Accra

The urban environment influences human health, safety and wellbeing. Cities in Africa are growing faster than other regions but have limited data to guide urban planning and policies. Our aim was to use smart sensing and analytics to characterise the spatial patterns and temporal dynamics of features of the urban environment relevant for health, liveability, safety and sustainability. We collected a novel dataset of 2.1 million time-lapsed day and night images at 145 representative locations throughout the Metropolis of Accra, Ghana. We manually labelled a subset of 1,250 images for 20 contextually relevant objects and used transfer learning with data augmentation to retrain a convolutional neural network to detect them in the remaining images. We identified 23.5 million instances of these objects including 9.66 million instances of persons (41% of all objects), followed by cars (4.19 million, 18%), umbrellas (3.00 million, 13%), and informally operated minibuses known as tro tros (2.94 million, 13%). People, large vehicles and market-related objects were most common in the commercial core and densely populated informal neighbourhoods, while refuse and animals were most observed in the peripheries. The daily variability of objects was smallest in densely populated settlements and largest in the commercial centre. Our novel data and methodology shows that smart sensing and analytics can inform planning and policy decisions for making cities more liveable, equitable, sustainable and healthy

Characterisation of urban environment and activity across space and time using street images and deep learning in Accra

The urban environment influences human health, safety and wellbeing. Cities in Africa are growing faster than other regions but have limited data to guide urban planning and policies. Our aim was to use smart sensing and analytics to characterise the spatial patterns and temporal dynamics of features of the urban environment relevant for health, liveability, safety and sustainability. We collected a novel dataset of 2.1 million time-lapsed day and night images at 145 representative locations throughout the Metropolis of Accra, Ghana. We manually labelled a subset of 1,250 images for 20 contextually relevant objects and used transfer learning with data augmentation to retrain a convolutional neural network to detect them in the remaining images. We identified 23.5 million instances of these objects including 9.66 million instances of persons (41% of all objects), followed by cars (4.19 million, 18%), umbrellas (3.00 million, 13%), and informally operated minibuses known as tro tros (2.94 million, 13%). People, large vehicles and market-related objects were most common in the commercial core and densely populated informal neighbourhoods, while refuse and animals were most observed in the peripheries. The daily variability of objects was smallest in densely populated settlements and largest in the commercial centre. Our novel data and methodology shows that smart sensing and analytics can inform planning and policy decisions for making cities more liveable, equitable, sustainable and healthy

Dosimetric precision of an ion beam tracking system

<p>Abstract</p> <p>Background</p> <p>Scanned ion beam therapy of intra-fractionally moving tumors requires motion mitigation. GSI proposed beam tracking and performed several experimental studies to analyse the dosimetric precision of the system for scanned carbon beams.</p> <p>Methods</p> <p>A beam tracking system has been developed and integrated in the scanned carbon ion beam therapy unit at GSI. The system adapts pencil beam positions and beam energy according to target motion.</p> <p>Motion compensation performance of the beam tracking system was assessed by measurements with radiographic films, a range telescope, a 3D array of 24 ionization chambers, and cell samples for biological dosimetry. Measurements were performed for stationary detectors and moving detectors using the beam tracking system.</p> <p>Results</p> <p>All detector systems showed comparable data for a moving setup when using beam tracking and the corresponding stationary setup. Within the target volume the mean relative differences of ionization chamber measurements were 0.3% (1.5% standard deviation, 3.7% maximum). Film responses demonstrated preserved lateral dose gradients. Measurements with the range telescope showed agreement of Bragg peak depth under motion induced range variations. Cell survival experiments showed a mean relative difference of -5% (-3%) between measurements and calculations within the target volume for beam tracking (stationary) measurements.</p> <p>Conclusions</p> <p>The beam tracking system has been successfully integrated. Full functionality has been validated dosimetrically in experiments with several detector types including biological cell systems.</p

Development of a duodenal gallstone ileus with gastric outlet obstruction (Bouveret syndrome) four months after successful treatment of symptomatic gallstone disease with cholecystitis and cholangitis: a case report

<p>Abstract</p> <p>Introduction</p> <p>Cases of gallstone ileus account for 1% to 4% of all instances of mechanical bowel obstruction. The majority of obstructing gallstones are located in the terminal ileum. Less than 10% of impacted gallstones are located in the duodenum. A gastric outlet obstruction secondary to a gallstone ileus is known as Bouveret syndrome. Gallstones usually enter the bowel through a biliary enteral fistula. Little is known about the formation of such fistulae in the course of gallstone disease.</p> <p>Case presentation</p> <p>We report the case of a 72-year-old Caucasian woman born in Germany with a gastric outlet obstruction due to a gallstone ileus (Bouveret syndrome), with a large gallstone impacted in the third part of the duodenum. Diagnostic investigations of our patient included plain abdominal films, gastroscopy and abdominal computed tomography, which showed a biliary enteric fistula between the gallbladder and the duodenal bulb. Our patient was successfully treated by laparotomy, duodenotomy, extraction of the stone, cholecystectomy, and resection of the fistula in a one-stage surgical approach. Histopathological examination showed chronic and acute cholecystitis, with perforated ulceration of the duodenal wall and acute purulent inflammation of the surrounding fatty tissue. Four months prior to developing a gallstone ileus our patient had been hospitalized for cholecystitis, a large gallstone in the gallbladder, cholangitis and a small obstructing gallstone in the common biliary duct. She had been treated with endoscopic retrograde cholangiopancreatography, endoscopic biliary sphincterotomy, balloon extraction of the common biliary duct gallstone, and intravenous antibiotics. At the time of her first presentation, abdominal ultrasound and endoscopic examination (including esophagogastroduodenoscopy and endoscopic retrograde cholangiopancreatography) had not shown any evidence of a biliary enteral fistula. In the four months preceding the gallstone ileus our patient had been asymptomatic.</p> <p>Conclusion</p> <p>In patients known to have gallstone disease presenting with symptoms of ileus, the differential diagnosis of a gallstone ileus should be considered even in the absence of preceding symptoms related to the gallbladder disease. Gallstones large enough to cause intestinal obstruction usually enter the bowel by a biliary enteral fistula. During the formation of such a fistula, patients can be asymptomatic.</p

Structural study of GaSb/AlSb strained-layer superlattice

Owing to the lattice mismatch between GaSb and AlSb, a superlattice consisting of alternating layers of these materials will be strained. We have carried out ion-channeling measurements by backscattering of 1.76-MeV He ions, and present an experimental procedure and a data-analysis technique to measure the difference in strain between the two individual layers of the superlattice. The data analysis is based on computer simulations of channeling, the accuracy of which is supported by the many fine details of the experiments reproduced in the simulations. X-ray rocking-curve analysis yielded detailed profiles of strains in directions perpendicular and parallel to the surface. The x-ray value for the strain present at an unirradiated spot on the crystal is in excellent agreement with the value calculated by elasticity theory. In the bombarded region, the values of strain are less than the value calculated by elasticity theory. It appears that bombardment by the He ions reduced the strain by 50% and created lateral inhomogeneities in the crystal structure

FDG-PET/CT in infections: the imaging method of choice?

[No abstract available

Standardising Clinical Caremaps: Model, Method and Graphical Notation for Caremap Specification

Standardising care can improve patient safety and outcomes, and reduce the cost of providing healthcare services. Caremaps were developed to standardise care, but contemporary caremaps are not standardised. Confusion persists in terms of terminology, structure, content and development process. Unlike existing methods in the literature, the approach, model and notation presented in this chapter pays special attention to incorporation of clinical decision points as first-class citizens within the modelling process. The resulting caremap with decision points is evaluated through creation of a caremap for women with gestational diabetes mellitus. The proposed method was found to be an effective way for comprehensively specifying all features of caremaps in a standardised way that can be easily understood by clinicians. This chapter contributes a new standardised method, model and notation for caremap content, structure and development