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We analyzed the chemical compositions of dust and sea‐salt particles in the EPICA Dome C (EDC) ice core during 26–7 kyr BP using an ice‐sublimation technique and compared the results with existing data of the Dome Fuji (DF) ice core. Combined with ion concentration data, our data suggested similar sea‐salt fluxes in both cores and significantly lower dust flux in the EDC core. The differences in modal size and aspect ratio of dust particles between the two cores support the dominance of Patagonian source suggested by earlier works. The compositions of calcic dust showed major change at ~17 kyr BP, possibly reflecting a relative increase in dust transported via the upper troposphere. The calcium sulfate fraction was higher in the DF core than in the EDC core after ~17 kyr BP, suggesting that higher Patagonian dust contribution to the DF region. Abundant NaCl particles were found in the DF core in comparison with the EDC core from the LGM to early Holocene, possibly because of the high concentration of terrestrial dust in the DF core that reduced acid availability for sea‐salt modification. During the Holocene, the lower NaCl fraction and Cl−/Na+ ratio in the EDC core suggested that most Cl− was lost to the atmosphere from snow at Dome C, while it was preserved at Dome Fuji as NaCl and solid solution. Key Points: Dust flux in the Dome C core is significantly lower than in the Dome Fuji core from the LGM to the early HoloceneComparison of dust size and aspect ratio between the two cores suggest dominance of Patagonian dust source during the LGMMost Cl was lost to the atmosphere from snow at Dome C, while it was preserved at Dome Fuji as NaCl and in solid solution in the Holocene [ABSTRACT FROM AUTHOR]

Investigation of organic compounds in ice cores can potentially unlock a wealth of new information in these climate archives. We present results from the first ever ice core drilled on sub‐Antarctic island Bouvet, representing a climatologically important but understudied region. We analyze a suite of novel and more familiar organic compounds in the ice core, alongside commonly measured ions. Methanesulfonic acid shows a significant, positive correlation to winter sea ice concentration, as does a fatty acid compound, oleic acid. Both may be sourced from spring phytoplankton blooms, which are larger following greater sea ice extent in the preceding winter. Oxalate, formate, and acetate are positively correlated to sea ice concentration in summer, but sources of these require further investigation. This study demonstrates the potential application of organic compounds from the marine biosphere in generating multiproxy sea ice records, which is critical in improving our understanding of past sea ice changes. Plain Language Summary: Ice cores are vertical cylinders of ice drilled from an ice sheet, younger at the top and older at the bottom. Particles emitted from plants and animals on land and in the ocean, containing organic chemical compounds, are carried by atmospheric circulation, deposited on the ice surface, and become trapped inside ice layers. They are a record of environmental conditions at the location and time the particles originally formed. Here, we look for a number of these organic compounds in an ice core from Bouvet Island in the sub‐Antarctic. We find the amounts of some are related to amounts of sea ice around the island in the spring. This is because the particles are originally emitted by phytoplankton, for which the amount of sea ice that year controls the amount of phytoplankton (more sea ice in the winter = greater area of sea ice break up in spring = more phytoplankton in spring). We find other organic compounds are related to amounts of sea ice in summer, but their sources are less well known. Combining these records with their relationships to sea ice will be useful in helping us to better understand sea ice changes in the past. Key Points: We analyzed a suite of organic compounds,alongside commonly measured ions, in the first ever shallow ice core from Bouvet IslandMultiple marine‐sourced organic compounds are detected throughout the coreOrganic compounds, alongside MSA, show significant positive correlations with sea ice [ABSTRACT FROM AUTHOR]

Viscous and other damping devices are often used as elements of seismic isolation systems. Despite the widespread application of nonlinear viscous systems particularly in Japan (with fewer applications in the USA and Taiwan), the application of viscous damping devices in isolation systems in the USA progressed intentionally toward the use of supplementary linear viscous devices due to the advantages offered by these devices. This paper presents experimental results on the behavior of seismically isolated structures with low damping elastomeric (LDE) and single friction pendulum (SFP) bearings with and without linear and nonlinear viscous dampers. The isolation systems are tested within a six-story structure configured as moment frame and then again as braced frame. Emphasis is placed both on the acquisition of data related to the structural system (drifts, story shear forces, and isolator displacements) and on non-structural systems (floor accelerations, floor spectral accelerations, and floor velocities). Moreover, the accuracy of analytical prediction of response is investigated based on the results of a total of 227 experiments, using 14 historic ground motions of far-fault and near-fault characteristics, on flexible moment frame and stiff braced frame structures isolated with LDE or SFP bearings and linear or nonlinear viscous dampers. It is concluded that when damping is needed to reduce displacement demands in the isolation system, linear viscous damping results in the least detrimental effect on the isolated structure. Moreover, the study concludes that the analytical prediction of peak floor accelerations and floor response spectra may contain errors that need to be considered when designing secondary systems. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Between 1989 and 2003, 100 transplants were performed in 96 patients at the pediatric nephrology unit of the Calvo Mackenna Children's Hospital. Mean age 10.9 ± 3.9 yr (1–17.6), 30% from LD. Donors were younger than 5 yr in five patients and all recipients received an ‘ en bloc’ graft. Original disease was hypo/dysplasia 27%, reflux nephropathy 22 and 17% chronic glomerulonephritis. The immunosuppressive protocol during the first period (n = 56, 1989–2000): Cyclosporine, steroids and azathioprine, and during the second period (n = 44, 2001–2003): FK, steroids, MMF and anti-CD25 antibody (mAbs). AR was reported in 22 patients, 11% in LD, 31% in DD (p < 0.01). The AR rate decreased from 40 to 8% after anti-CD25 monoclonal induction. Patient actuarial survival rate at 1, 3 and 5 yr was 100% for LD and 96% for DD. The overall actuarial graft survival at 1,3, and 5 yr was 96.7, 96.7 and 71% for LD and 89, 76 and 73% for DD donors. Graft survival rate improved from the first period (1989–2000) to the second period (2001–2003; p = 0.05). No difference in graft survival rate with HLA-A,B,DR matching was found. Graft survival rate was better when cold ischemia time was <24 h (p < 0.01). CMV infections increased from 19 to 40% when MMF and anti-CD25 Ab were introduced (p < 0.01). The height/age Z score at 1, 3 and 5 yr post-transplant was −2.2, −2.1, −2.2, respectively, for children older than 7 yr and −1.8, −1.9, −2.1 for those transplanted younger than 7 yr of age who were switched to alternate day steroids (p < 0.01). The cause of graft lost was: chronic rejection eight, non-adherence four, AR four and vascular thrombosis two. The cause of death in two patients was fungus septicemia and accelerated rejection. Pediatric renal transplantation can be performed in our group with acceptable morbidity, low mortality and graft survival rates similar to other reports in North America and Western Europe. Graft survival rate improved with newer immunosuppression and greater experience at the center. Management of non-adherence and chronic rejection remain the major challenges. [ABSTRACT FROM AUTHOR]

Two conflicting predictions have emerged regarding the effect of low–cost information on price. The first states that all Internet retailers will charge the same low price for mass produced goods. The second states that Internet retailers will differentiate to avoid intense price competition. Using data collected in April 1999 on the prices of 107 books in thirteen online and two physical bookstores, we find similar average prices online and in physical stores and substantial price dispersion online. Analysis of product differentiation yields no clear results. The substantial premium charged by Amazon provides indirect evidence of product differentiation. [ABSTRACT FROM AUTHOR]

Summary The microstructure and location of impurities in polar ice are of great relevance to ice core studies. We describe a reliable method to examine ice in the scanning electron microscope (SEM). Specimens were cut in a cold room and could have their surfaces altered by sublimation either before (pre-etching) or after (etching) introduction to the cryo-chamber of the SEM. Pre-etching was used to smooth surfaces, whilst etching stripped away layers from the specimen surface, aiding the location of particles in situ , and allowing embedded structures to be revealed. X-ray analysis was used to determine the composition of localized impurities, which in some cases had been concentrated on the surface by etching. Examining uncoated surfaces was found to be advantageous and did not detract from qualitative X-ray analysis. Imaging uncoated was performed at low accelerating voltages and probe currents to avoid problems of surface charging. [ABSTRACT FROM AUTHOR]

- Renographic studies under standardised conditions of maximal diuresis provoked by infusion of hypotonic saline and frusemide were made on 51 patients with 54 dilated upper urinary tract systems in order to distinguish obstructed from non-obstructed systems. Of the 23 systems judged on clinical and radiological grounds to be obstructed only 12 were in fact obstructed following infusion of hypotonic saline and frusemide. In 10 of these systems (1 0 patients) an Anderson-Hynes pyeloplasty was carried out. All systems showed improved renal function after operation and the renographic pattern became non-obstructed. [ABSTRACT FROM AUTHOR]

- Renographic studies under standardised conditions of maximal diuresis provoked by hypotonic saline infusion and frusemide were used in 17 patients with dilatation of the upper urinary tract in order to distinguish between obstructed and non-obstructed urinary tracts. Of the six patients who were obstructed on clinical and X-ray evidence only three showed an obstructed pattern on the renographic curves after maximal diuresis. After operation these three patients showed improvement in both renographic curve and functional images of the renal parenchyma. A new method of identifying the parenchymal area is described. [ABSTRACT FROM AUTHOR]

BSTRACT An NMR method was developed for detection of the sublimation period endpoint during the freeze-drying of potato pieces. Longitudinal (T1 and transverse (T2) relaxation times were estimated using rapid NMR methods. Samples were immediately examined to determine presence of a frozen core. The plot of T1 vs T2 showed an abrupt increase at a point corresponding to the complete elimination of the frozen core. Similar Tj vs T2 curves were observed when monitoring freeze-drying of a single potato piece inside the NMR probe-head. The detection of an anomalous freeze-drying is possible by monitoring the T1 the T2 or the free induction decay signal. [ABSTRACT FROM AUTHOR]

We have developed a method of diuretic renography for the assessment of upper urinary tract obstruction in children. A maximal diuresis under standardised conditions is obtained by forced intravenous hydration over a 2-h period prior to renography. We evaluated the predictive value of this method for the clinical and functional outcome in 73 children with apparent unilateral pelviureteric junction obstruction. The predictive value of a nonobstructive pattern was 94%, while the predictive value of an obstructive pattern could not be assessed accurately because the patients concerned subsequently underwent operation. The method is safe and reliable and offers advantages over conventional diuretic renography. [ABSTRACT FROM AUTHOR]