We live in a visual culture, and visual evidence is increasingly central to social research. In this collection an international range of experts explain how they have used visual methods in their ...own research, examine their advantages and limitations, and show how they have been used alongside other research techniques. Contributors explore the following ideas: * self and identity * visualizing domestic space * visualizing urban landscapes * visualizing social change. The collection showcases different methods in different contexts through the examination of a variety of topical issues. Methods covered include photo and video diaries, the use of images produced by respondents, the use of images as prompts in interviews and focus groups, documentary photography, photographic inventory and visual ethnography. The result is an exciting and original collection that will be indispensable for any student, academic or researcher interested in the use of visual methods.
Introduction Working With Visible Evidence: An Invitation and Some Practical Advice Part 1: Picturing the Self, Identity and Domesticated Space 1. My Visual Diary 2. Reflecting the Self 3. Mapping the Spatial in Shared Household Life: A Missed Opportunity? 4. Imaging the Intangible 5. Wednesday-Night Bowling: Reflections on Cultures of a Rural Working Class Part 2: Picturing the City, Sociality and Post-Industrial Change 6. Researching and Writing Everyday Accounts of the City: An Introduction to the Diary-Photo Diary-Interview Method 7. Listening with our Eyes: Portrait as Urban Encounter 8. Amsterdam and Chicago: Seeing the Macro-Characteristics of Gentrification 9. The Visual & the Verbal: The Interaction of Images and Discussion in Exploring Cultural Change 10. Telling the Story of Linda Lord Through Photographs Afterword
Evaluation of a first seizure Adams, Stephen M; Knowles, Paul D
American family physician,
2007-May-01, 20070501, Letnik:
75, Številka:
9
Journal Article
Recenzirano
Seizure is a common presentation in the emergency care setting, and new-onset epilepsy is the most common cause of unprovoked seizures. The patient history and physical examination should direct the ...type and timing of laboratory and imaging studies. No single sign, symptom, or test dearly differentiates a seizure from a nonseizure event (e.g., syncope, pseudoseizure). Electroencephalography is recommended for patients presenting with a first seizure, and neuroimaging is recommended for adults. Neuroimaging also should be performed in children with risk factors such as head trauma, focal neurologic deficits, or a history of malignancy. Magnetic resonance imaging is preferred over computed tomography except when acute intracranial bleeding is suspected. The most common laboratory findings associated with a seizure are abnormal sodium and glucose levels. Patients with a normal neurologic examination, normal test results, and no structural brain disease do not require hospitalization or antiepileptic medications. Treatment with antiepileptic medications reduces the one- to two-year risk of recurrent seizures but does not reduce the long-term risk of recurrence and does not affect remission rates. Regardless of etiology, a seizure diagnosis severely limits a patient's driving privileges, although laws vary by state.
Clogging is a major operational and maintenance issue associated with the use of subsurface flow wetlands for wastewater treatment, and can ultimately limit the lifetime of the system. This review ...considers over two decades of accumulated knowledge regarding clogging in both vertical and horizontal subsurface flow treatment wetlands. The various physical, chemical and biological factors responsible for clogging are identified and discussed. The occurrence of clogging is placed into the context of various design and operational parameters such as wastewater characteristics, upstream treatment processes, intermittent or continuous operation, influent distribution, and media type. This information is then used to describe how clogging develops within, and subsequently impacts, common variants of subsurface flow treatment wetland typically used in the U.S., U.K., France and Germany. Comparison of these systems emphasized that both hydraulic loading rate and solids loading rate need to be considered when designing systems to operate robustly, i.e. hydraulic overloading makes horizontal-flow tertiary treatment systems in the U.K. more susceptible to clogging problems than vertical-flow primary treatment systems in France. Future research should focus on elucidating the underlying mechanisms of clogging as they relate to the design, operation, and maintenance of subsurface flow treatment wetlands.
In this work we demonstrate the potential of permanent magnet based magnetic resonance sensors to monitor and assess the extent of pore clogging in water filtration systems. The performance of the ...sensor was tested on artificially clogged gravel substrates and on gravel bed samples from constructed wetlands used to treat wastewater. Data indicate that the spin lattice relaxation time is linearly related to the hydraulic conductivity in such systems. In addition, within biologically active filters we demonstrate the ability to determine the relative ratio of biomass to abiotic solids, a measurement which is not possible using alternative techniques.
This paper reviews the state of the art in measuring, modeling, and managing clogging in subsurface-flow treatment wetlands. Methods for measuring in situ hydraulic conductivity in treatment wetlands ...are now available, which provide valuable insight into assessing and evaluating the extent of clogging. These results, paired with the information from more traditional approaches (e.g., tracer testing and composition of the clog matter) are being incorporated into the latest treatment wetland models. Recent finite element analysis models can now simulate clogging development in subsurface-flow treatment wetlands with reasonable accuracy. Various management strategies have been developed to extend the life of clogged treatment wetlands, including gravel excavation and/or washing, chemical treatment, and application of earthworms. These strategies are compared and available cost information is reported.
► Critical review of current knowledge on clogging measurement and management. ► The combination of in situ and laboratory tests provide the best information. ► Mathematical models available for predicting clogging still in development. ► Preventative and corrective strategies are employed to manage wetland clogging.
Laser spectroscopy of muonic deuterium Pohl, Randolf; Nez, François; Fernandes, Luis M. P. ...
Science (American Association for the Advancement of Science),
08/2016, Letnik:
353, Številka:
6300
Journal Article
Recenzirano
Odprti dostop
The deuteron is the simplest compound nucleus, composed of one proton and one neutron. Deuteron properties such as the root-mean-square charge radius rd and the polarizability serve as important ...benchmarks for understanding the nuclear forces and structure. Muonic deuterium μd is the exotic atom formed by a deuteron and a negative muon μ⁻. We measured three 2S-2P transitions in μd and obtain rd = 2.12562(78) fm, which is 2.7 times more accurate but 7.5σ smaller than the CODATA-2010 value rd = 2.1424(21) fm. The μd value is also 3.5σ smaller than the rd value from electronic deuterium spectroscopy. The smaller rd, when combined with the electronic isotope shift, yields a "small" proton radius rp, similar to the one from muonic hydrogen, amplifying the proton radius puzzle.
Accurate knowledge of the charge and Zemach radii of the proton is essential, not only for understanding its structure but also as input for tests of bound-state quantum electrodynamics and its ...predictions for the energy levels of hydrogen. These radii may be extracted from the laser spectroscopy of muonic hydrogen (μp, that is, a proton orbited by a muon). We measured the $2{\mathrm{S}}_{1/2}^{\mathrm{F}=0}-2{\mathrm{P}}_{3/2}^{\mathrm{F}=1}$ transition frequency in μp to be 54611.16(1.05) gigahertz (numbers in parentheses indicate one standard deviation of uncertainty) and reevaluated the $2{\mathrm{S}}_{1/2}^{\mathrm{F}=1}-2{\mathrm{P}}_{3/2}^{\mathrm{F}=1}$ transition frequency, yielding 49881.35(65) gigahertz. From the measurements, we determined the Zemach radius, r Z = 1.082(37) femtometers, and the magnetic radius, r M = 0.87(6) femtometer, of the proton. We also extracted the charge radius, r E = 0.84087(39) femtometer, with an order of magnitude more precision than the 2010-CODATA value and at 7σ variance with respect to it, thus reinforcing the proton radius puzzle.
The size of the proton dos Santos, Joaquim M. F; Fernandes, Luis M. P; Liu, Yi-Wei ...
Nature (London),
07/2010, Letnik:
466, Številka:
7303
Journal Article
Recenzirano
The proton is the primary building block of the visible Universe, but many of its properties—such as its charge radius and its anomalous magnetic moment—are not well understood. The root-mean-square ...charge radius, rp, has been determined with an accuracy of 2 per cent (at best) by electron–proton scattering experiments. The present most accurate value of rp (with an uncertainty of 1 per cent) is given by the CODATA compilation of physical constants. This value is based mainly on precision spectroscopy of atomic hydrogen and calculations of bound-state quantum electrodynamics (QED; refs 8, 9). The accuracy of rp as deduced from electron–proton scattering limits the testing of bound-state QED in atomic hydrogen as well as the determination of the Rydberg constant (currently the most accurately measured fundamental physical constant). An attractive means to improve the accuracy in the measurement of rp is provided by muonic hydrogen (a proton orbited by a negative muon); its much smaller Bohr radius compared to ordinary atomic hydrogen causes enhancement of effects related to the finite size of the proton. In particular, the Lamb shift (the energy difference between the 2S1/2 and 2P1/2 states) is affected by as much as 2 per cent. Here we use pulsed laser spectroscopy to measure a muonic Lamb shift of 49,881.88(76) GHz. On the basis of present calculations of fine and hyperfine splittings and QED terms, we find rp = 0.84184(67) fm, which differs by 5.0 standard deviations from the CODATA value of 0.8768(69) fm. Our result implies that either the Rydberg constant has to be shifted by −110 kHz/c (4.9 standard deviations), or the calculations of the QED effects in atomic hydrogen or muonic hydrogen atoms are insufficient.
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