69 research outputs found
Flight Dreams
When I was a child, I wanted to fly. Not in airplanes, helicopters, hot-air balloons, or rockets, but of my own volition - as birds and bats and butterflies flew. I was envious of their ability to fly out of harm\u27s way at a moment\u27s notice and their defiance of gravity\u27s pull. But most of all I wanted to experience the sensation of flight - the lightness, the uplift of air first beneath my arms as I took off and then beneath my horizontal body. I wanted to roll, dive, rise, and bank. I didn\u27t expect to fly above the clouds. But I did expect to skim the tree tops, to roost on chimneys and steeples, and to glide above my earthbound classmates trudging to school, one foot in front of the other. I wanted to be above it all, even if that meant wind-blown hair, dry eyes, and bugs between my teeth
Household Words
The Germanic words for home may have been derived from two Indo-European words: kei, which means lying or settling down, a bed or couch, as well as something beloved, and ksêmas, which means safe dwelling. These linguistic ancestors also yield the Greek koiman, to put to sleep, which is the root of koimeterion, a sleeping place or cemetery. In time, the word for home in several European languages (ham in Anglo-Saxon; heimr in Old Norse; háims in Gothic; kemas or kaímas in Lithuanian; caymis in Old Prussian, etc.) also came to mean a village, town, or collection of dwellings. Home is both a community and a safe beloved place to lay down your living or dead body for the night or for eternity.
Now, we use the word home to refer to one\u27s fixed residence, the center of domestic life and interests as well as the center of the neighborhood, city or town, state and region to which one properly belongs, in which one\u27s affections center, in which one finds refuge or rest. But in the past several decades in the United States, Australia, and increasingly elsewhere, home also has come to designate a building that is a place of private residence. According to the real estate industry\u27s limited and desacralized definition of the word, home is just a physical structure, one\u27s mailing address, for the time being. This makes light of the fact that some of the despair felt by people living in refugee camps or homeless shelters is that they are not homeless. They know where home is or was or should be. They know it as the place where they would most prefer to lay their bodies down, the place they dream of when they sleep, a place and circumstance that can\u27t be bought or sold, that persists even when taken from them by bombs, tanks, tornadoes, eviction notices, or wrecking balls
Nine-Mile Prairie
I’m going there today. But I can’t find the right preposition to capture the experience. Will I go onto the prairie, as if it were the upper surface of something, a plane or a platform to pass over? Will I go into the prairie, as if it were something that can surround or envelop me like an economic recession or a waiting room? Will I go through the prairie, as if it were a substance like water or an ordeal like menopause to move into and beyond? Or will I go around the prairie, metaphorically skirting its edges, since it is an enigma whose meaning I’ve yet to discover?
And what of the articles a or the? Will I go to a prairie, a being a fragment of the once vast grassland in the center of North America, or will I go to the prairie, the whole from which the relict is preserved or somehow escaped destruction, a whole that still exists, even if only in the imagination? What I can say: I’m going there today
The Activities and Program of the American Association of Law Libraries
Denna rapport kommer att behandla konstruktion och design av ett småskaligt portabelt solvärmesystem. Rapportens första del är en teoretisk referensram som ligger till grund för byggandet av en prototyp av den behandlade solvärmetypen som har testats för att se vilken prestanda som uppnåtts och hur systemet förhåller sig till en given målfunktion. Prototypen togs fram med hjälp av produktutvecklingsmetodik, vilken även finns utförligt förklarad i rapporten. Verkningsgraden för den byggda prototypen beräknades efter tester till 65 % och är dimensionerad för 70 liter vatten. Solvärmesystemet som uppvärmningsalternativ och dess konkurrenskraft bland andra uppvärmningsalternativ har också studerats och slutsatsen dragits att solvärme har många miljömässigt positiva aspekter men lång pay off-tid per utvunnen kWh vilket gör att det kan anses som ett mindre attraktivt alternativ i Sverige jämfört med länder med högre solinstrålning
A Deep Learning Approach for Burned Area Segmentation with Sentinel-2 Data
Wildfires have major ecological, social and economic consequences. Information about the extent of burned areas is essential to assess these consequences and can be derived from remote sensing data. Over the last years, several methods have been developed to segment burned areas with satellite imagery. However, these methods mostly require extensive preprocessing, while deep learning techniques - which have successfully been applied to other segmentation tasks - have yet to be fully explored. In this work, we combine sensor-specific and methodological developments from the past few years and suggest an automatic processing chain, based on deep learning, for burned area segmentation using mono-temporal Sentinel-2 imagery. In particular, we created a new training and validation dataset, which is used to train a convolutional neural network based on a U-Net architecture. We performed several tests on the input data and reached optimal network performance using the spectral bands of the visual, near infrared and shortwave infrared domains. The final segmentation model achieved an overall accuracy of 0.98 and a kappa coefficient of 0.94
Proximal tubule morphology after single nephron obstruction in the rat kidney
Proximal tubule morphology after single nephron obstruction in the rat kidney. This study examined the effects on proximal tubule morphology of blocking single nephrons with paraffin wax for one day, one week, or one month in the rat. Proximal tubule lumens were blocked with a short column of wax using micropuncture. Chronically blocked and control (normal) tubules were fixed by either intravascular or intraluminal perfusion of glutaraldehyde solution. Proximal tubule segments down-stream to the wax block were examined by light and transmission electron microscopy. Intraluminal Alcian blue dye, serial sectioning, and nephron microdissection techniques were used to identify nephrons. One day after obstruction, all proximal tubule cells downstream to the block were injured. Some recovery was seen. S1 and S2 segments showed more severe damage than S3 segments. Alcian blue, which normally is excluded from cells, entered the cytoplasm of some damaged S1-S2 cells. After one week of obstruction, the tubule appeared to have reconstituted itself, but cells were less differentiated than normal. One month after obstruction, blocked tubules were atrophied. Tubule cells were simplified and were surrounded by a thickened basement membrane. The results suggest that prolonged proximal tubule blockade produces injury and atrophy of the proximal tubule probably due to ischemia and interruption of normal reabsorptive activity
Improving reliability in flood mapping by generating a global seasonal reference water mask using Sentinel-1/2 time-series data
Variable intra-annual climatic and hydrologic conditions result in many regions of the world in a strong seasonality of the water extent throughout the year. This behaviour, however, is usually not reflected in satellite-based flood emergency mapping. This may lead to non-reliable representations of the flood extent and to misleading information within disaster management activities. In order to be able to separate flooding from normally present seasonal water coverage, up-to-date, high-resolution information on the seasonal water cover is crucial. In this work, we present an automatic methodology to generate a global and consistent permanent and seasonal reference water product based on high resolution Earth Observation data, specifically designed for the use within flood mapping activities. The water masks are primarily based on the time-series analysis of optical Sentinel-2 imagery, which are complemented by Sentinel-1 Synthetic Aperture Radar-based information in data scarce regions. The methodology has been
developed based on data of five globally distributed study areas (Australia, Germany, India, Mozambique, and Sudan). Within this work results for Australia and India are demonstrated and are systematically compared with external reference water products. Results show, that by using the proposed product it is possible to give a more reliable picture on flood-affected areas in the frame of disaster response
The Woody Guthrie Centennial Bibliography
This bibliography updates two extensive works designed to include comprehensively all significant works by and about Woody Guthrie. Richard A. Reuss published A Woody Guthrie Bibliography, 1912–1967 in 1968 and Jeffrey N. Gatten\u27s article “Woody Guthrie: A Bibliographic Update, 1968–1986” appeared in 1988. With this current article, researchers need only utilize these three bibliographies to identify all English-language items of relevance related to, or written by, Guthrie
Efficacy and safety of statin therapy in older people: a meta-analysis of individual participant data from 28 randomised controlled trials
Background:
Statin therapy has been shown to reduce major vascular events and vascular mortality in a wide range of individuals, but there is uncertainty about its efficacy and safety among older people. We undertook a meta-analysis of data from all large statin trials to compare the effects of statin therapy at different ages.
Methods:
In this meta-analysis, randomised trials of statin therapy were eligible if they aimed to recruit at least 1000 participants with a scheduled treatment duration of at least 2 years. We analysed individual participant data from 22 trials (n=134 537) and detailed summary data from one trial (n=12 705) of statin therapy versus control, plus individual participant data from five trials of more intensive versus less intensive statin therapy (n=39 612). We subdivided participants into six age groups (55 years or younger, 56–60 years, 61–65 years, 66–70 years, 71–75 years, and older than 75 years). We estimated effects on major vascular events (ie, major coronary events, strokes, and coronary revascularisations), cause-specific mortality, and cancer incidence as the rate ratio (RR) per 1·0 mmol/L reduction in LDL cholesterol. We compared proportional risk reductions in different age subgroups by use of standard χ2 tests for heterogeneity when there were two groups, or trend when there were more than two groups.
Findings:
14 483 (8%) of 186 854 participants in the 28 trials were older than 75 years at randomisation, and the median follow-up duration was 4·9 years. Overall, statin therapy or a more intensive statin regimen produced a 21% (RR 0·79, 95% CI 0·77–0·81) proportional reduction in major vascular events per 1·0 mmol/L reduction in LDL cholesterol. We observed a significant reduction in major vascular events in all age groups. Although proportional reductions in major vascular events diminished slightly with age, this trend was not statistically significant (ptrend=0·06). Overall, statin or more intensive therapy yielded a 24% (RR 0·76, 95% CI 0·73–0·79) proportional reduction in major coronary events per 1·0 mmol/L reduction in LDL cholesterol, and with increasing age, we observed a trend towards smaller proportional risk reductions in major coronary events (ptrend=0·009). We observed a 25% (RR 0·75, 95% CI 0·73–0·78) proportional reduction in the risk of coronary revascularisation procedures with statin therapy or a more intensive statin regimen per 1·0 mmol/L lower LDL cholesterol, which did not differ significantly across age groups (ptrend=0·6). Similarly, the proportional reductions in stroke of any type (RR 0·84, 95% CI 0·80–0·89) did not differ significantly across age groups (ptrend=0·7). After exclusion of four trials which enrolled only patients with heart failure or undergoing renal dialysis (among whom statin therapy has not been shown to be effective), the trend to smaller proportional risk reductions with increasing age persisted for major coronary events (ptrend=0·01), and remained non-significant for major vascular events (ptrend=0·3). The proportional reduction in major vascular events was similar, irrespective of age, among patients with pre-existing vascular disease (ptrend=0·2), but appeared smaller among older than among younger individuals not known to have vascular disease (ptrend=0·05). We found a 12% (RR 0·88, 95% CI 0·85–0·91) proportional reduction in vascular mortality per 1·0 mmol/L reduction in LDL cholesterol, with a trend towards smaller proportional reductions with older age (ptrend=0·004), but this trend did not persist after exclusion of the heart failure or dialysis trials (ptrend=0·2). Statin therapy had no effect at any age on non-vascular mortality, cancer death, or cancer incidence.
Interpretation:
Statin therapy produces significant reductions in major vascular events irrespective of age, but there is less direct evidence of benefit among patients older than 75 years who do not already have evidence of occlusive vascular disease. This limitation is now being addressed by further trials.
Funding:
Australian National Health and Medical Research Council, National Institute for Health Research Oxford Biomedical Research Centre, UK Medical Research Council, and British Heart Foundation
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