| 1. |
- Fretwell, P., et al.
(författare)
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Bedmap2 : improved ice bed, surface and thickness datasets for Antarctica
- 2013
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Ingår i: The Cryosphere. - : Copernicus GmbH. - 1994-0416 .- 1994-0424. ; 7:1, s. 375-393
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Tidskriftsartikel (refereegranskat)abstract
- We present Bedmap2, a new suite of gridded products describing surface elevation, ice-thickness and the seafloor and subglacial bed elevation of the Antarctic south of 60 degrees S. We derived these products using data from a variety of sources, including many substantial surveys completed since the original Bedmap compilation (Bedmap1) in 2001. In particular, the Bedmap2 ice thickness grid is made from 25 million measurements, over two orders of magnitude more than were used in Bedmap1. In most parts of Antarctica the subglacial landscape is visible in much greater detail than was previously available and the improved data-coverage has in many areas revealed the full scale of mountain ranges, valleys, basins and troughs, only fragments of which were previously indicated in local surveys. The derived statistics for Bedmap2 show that the volume of ice contained in the Antarctic ice sheet (27 million km(3)) and its potential contribution to sea-level rise (58 m) are similar to those of Bedmap1, but the mean thickness of the ice sheet is 4.6% greater, the mean depth of the bed beneath the grounded ice sheet is 72m lower and the area of ice sheet grounded on bed below sea level is increased by 10 %. The Bedmap2 compilation highlights several areas beneath the ice sheet where the bed elevation is substantially lower than the deepest bed indicated by Bedmap1. These products, along with grids of data coverage and uncertainty, provide new opportunities for detailed modelling of the past and future evolution of the Antarctic ice sheets.
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| 2. |
- Janssens-Maenhout, G., et al.
(författare)
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Toward an operational anthropogenic CO2 emissions monitoring and verification support capacity
- 2020
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Ingår i: Bulletin of the American Meteorological Society. - 0003-0007. ; 101:8, s. 1439-1451
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Tidskriftsartikel (refereegranskat)abstract
- Under the Paris Agreement (PA), progress of emission reduction efforts is tracked on the basis of regular updates to national greenhouse gas (GHG) inventories, referred to as bottom-up estimates. However, only top-down atmospheric measurements can provide observation-based evidence of emission trends. Today, there is no internationally agreed, operational capacity to monitor anthropogenic GHG emission trends using atmospheric measurements to complement national bottom-up inventories. The European Commission (EC), the European Space Agency, the European Centre for Medium-Range Weather Forecasts, the European Organisation for the Exploitation of Meteorological Satellites, and international experts are joining forces to develop such an operational capacity for monitoring anthropogenic CO2 emissions as a new CO2 service under the EC's Copernicus program. Design studies have been used to translate identified needs into defined requirements and functionalities of this anthropogenic CO2 emissions Monitoring and Verification Support (CO2MVS) capacity. It adopts a holistic view and includes components such as atmospheric spaceborne and in situ measurements, bottom-up CO2 emission maps, improved modeling of the carbon cycle, an operational data-assimilation system integrating top-down and bottom-up information, and a policy-relevant decision support tool. The CO2MVS capacity with operational capabilities by 2026 is expected to visualize regular updates of global CO2 emissions, likely at 0.05° x 0.05°. This will complement the PA's enhanced transparency framework, providing actionable information on anthropogenic CO2 emissions that are the main driver of climate change. This information will be available to all stakeholders, including governments and citizens, allowing them to reflect on trends and effectiveness of reduction measures. The new EC gave the green light to pass the CO2MVS from exploratory to implementing phase.
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| 3. |
- Ballantyne, Kaye N., et al.
(författare)
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Toward Male Individualization with Rapidly Mutating Y-Chromosomal Short Tandem Repeats
- 2014
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Ingår i: Human Mutation. - : John Wiley & Sons. - 1059-7794 .- 1098-1004. ; 35:8, s. 1021-1032
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Tidskriftsartikel (refereegranskat)abstract
- Relevant for various areas of human genetics, Y-chromosomal short tandem repeats (Y-STRs) are commonly used for testing close paternal relationships among individuals and populations, and for male lineage identification. However, even the widely used 17-loci Yfiler set cannot resolve individuals and populations completely. Here, 52 centers generated quality-controlled data of 13 rapidly mutating (RM) Y-STRs in 14,644 related and unrelated males from 111 worldwide populations. Strikingly, greater than99% of the 12,272 unrelated males were completely individualized. Haplotype diversity was extremely high (global: 0.9999985, regional: 0.99836-0.9999988). Haplotype sharing between populations was almost absent except for six (0.05%) of the 12,156 haplotypes. Haplotype sharing within populations was generally rare (0.8% nonunique haplotypes), significantly lower in urban (0.9%) than rural (2.1%) and highest in endogamous groups (14.3%). Analysis of molecular variance revealed 99.98% of variation within populations, 0.018% among populations within groups, and 0.002% among groups. Of the 2,372 newly and 156 previously typed male relative pairs, 29% were differentiated including 27% of the 2,378 father-son pairs. Relative to Yfiler, haplotype diversity was increased in 86% of the populations tested and overall male relative differentiation was raised by 23.5%. Our study demonstrates the value of RMY-STRs in identifying and separating unrelated and related males and provides a reference database.
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| 4. |
- Budelmann, D., et al.
(författare)
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Antiferromagnetic and superconducting proximity effects in YBa2Cu3O7-delta/PrBa2Cu3O7-delta superlattices
- 2003
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Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 67, s. 140507-
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Tidskriftsartikel (refereegranskat)abstract
- We investigate the interplay between the antiferromagnetic and superconducting order parameters in YBa2Cu3O7-delta/PrBa2Cu3O7-delta superlattices by inelastic light scattering. The ratio of superconducting to antiferromagnetic order is varied through different modulations 4/6, 4/9, and 4/12 of (Y/Pr)Ba2Cu3O7-delta layers. This allows us to identify the proximity effect of the superconducting order parameter into the antiferromagnetic barrier as signified, e.g., by the sharpening of the two-magnon excitation. This proximity effect as well as gap feature and phonon anomalies reveals the delicate interplay between superconducting and antiferromagnetic order parameters.
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| 5. |
- Claesson, B, et al.
(författare)
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Biliary microflora in acute cholecystitis and the clinical implications
- 1984
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Ingår i: Acta Chirurgica Scandinavica. - 0001-5482. ; 150:3, s. 229-237
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Tidskriftsartikel (refereegranskat)abstract
- A prospective bacteriologic investigation was made in 43 consecutive patients (mean age 63 years) operated on for acute cholecystitis. Gallbladder bile and wall were cultured, using four methods and with special attention to optimal anaerobic technique. Cultures were positive in 72% of the patients, yielding a wide variety of species (21 species among 48 isolates). Anaerobes constituted 23% of the isolates. Cultures from gallbladder bile and from gallbladder wall gave almost identical results, as did sampling at the beginning and at the end of cholecystectomy. Bactibilia was found in all patients operated on within 48 hours after the onset of symptoms. Bactibilia and postoperative septic complications showed statistically significant correlation with high patient age. Bactibilia and gallbladder gangrene were significantly correlated with preoperative temperature greater than 38.5 degrees C. There was coincidence of strains isolated from local wound sepsis and from peroperatively sampled gallbladder bile. Adequate preoperative or peroperative antibiotic therapy according to susceptibility testing was associated with significantly reduced rate of postoperative septic complications. The study indicates that bacteria are present early in the course of acute cholecystitis and that they are causally important for postoperative morbidity and mortality.
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| 6. |
- Claesson, B E, et al.
(författare)
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Microflora of the gallbladder related to duration of acute cholecystitis
- 1986
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Ingår i: Surgery Gynecology and Obstetrics. - 0039-6087. ; 162:6, s. 531-535
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Tidskriftsartikel (refereegranskat)abstract
- The microflora of the bile and wall of the gallbladder was prospectively investigated in 104 nonselected consecutive patients treated with early cholecystectomy for acute cholecystitis after an average hospital stay of 1.8 days. The chief purpose was to relate the findings of cultures to duration of the illness. Special attention was paid to anaerobic isolation techniques. The cultures yielded 107 strains, representing 36 species, with overall agreement between four different sampling procedures. Aerobic gram-negative rods predominated, followed by streptococci and anaerobes (48, 31 and 15 per cent, respectively). The incidence of positive culture results (always greater than or equal to 10(6) colon forming units per milliliter) was 81 per cent among the patients who underwent operation within two days from the onset of symptoms and 50 to 65 per cent after longer preoperative intervals. The shorter interval was significantly more often associated with growth solely of anaerobes (p = 0.03). Postoperative sepsis was caused by biliary bacteria and not related to preoperative duration of illness. Appropriate perioperative antibiotic coverage significantly reduced sepsis--3 versus 20 per cent (p = 0.05).
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| 7. |
- Claesson, B E, et al.
(författare)
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Selective cefuroxime prophylaxis following colorectal surgery based on intra-operative dipslide culture
- 1986
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Ingår i: British Journal of Surgery. - : Oxford University Press (OUP). - 1365-2168 .- 0007-1323. ; 73:12, s. 953-957
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Tidskriftsartikel (refereegranskat)abstract
- The concept of a very limited effective period for prophylactic antibiotic action was challenged in a prospective, controlled and randomized study featuring a simplified method for assessing the degree of contamination in the operative field during colorectal surgery. The 226 patients were given 1 g metronidazole IV on induction of anaesthesia and 12 h postoperatively. Following standardized saline irrigation of the abdominal cavity, a uriculture dipslide was dipped in the residual fluid just before abdominal closure. The dipslide was incubated for 18 h, and colony counts of coliforms and Staphylococcus aureus were made. The number of colony-forming units (CFU) was classified as 0, 1-4 or greater than or equal to 5 (n = 123, 33 and 70). The patients with CFU greater than or equal to 5 were randomized to receive cefuroxime (1.5 g IV/8 h for 2 days) or no more antibiotics. In the patients given only metronidazole, the incidence of postoperative infections rose with the colony counts (5.7, 9.1 and 41.2 per cent with CFU 0, 1-4 and greater than or equal to 5). Addition of cefuroxime reduced the 41.2 per cent infection rate to 8.3 per cent (P = 0.003). The method thus identified a high-risk group in which a short postoperative course of cefuroxime significantly lowered the rate of sepsis.
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| 8. |
- Eklund, Anders, et al.
(författare)
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The Pressure Difference between Eye and Brain Changes with Posture
- 2016
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Ingår i: Annals of Neurology. - : Wiley. - 0364-5134 .- 1531-8249. ; 80:2, s. 269-276
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The discovery of a posture-dependent effect on the difference between intraocular pressure (IOP) and intracranial pressure (ICP) at the level of lamina cribrosa could have important implications for understanding glaucoma and idiopathic intracranial hypertension and could help explain visual impairments in astronauts exposed to microgravity. The aim of this study was to determine the postural influence on the difference between simultaneously measured ICP and IOP.Methods: Eleven healthy adult volunteers (age = 46 ± 10 years) were investigated with simultaneous ICP, assessed through lumbar puncture, and IOP measurements when supine, sitting, and in 9° head-down tilt (HDT). The trans–lamina cribrosa pressure difference (TLCPD) was calculated as the difference between the IOP and ICP. To estimate the pressures at the lamina cribrosa, geometrical distances were estimated from magnetic resonance imaging and used to adjust for hydrostatic effects.Results: The TLCPD (in millimeters of mercury) between IOP and ICP was 12.3 ± 2.2 for supine, 19.8 ± 4.6 for sitting, and 6.6 ± 2.5 for HDT. The expected 24-hour average TLCPD on earth—assuming 8 hours supine and 16 hours upright—was estimated to be 17.3mmHg. By removing the hydrostatic effects on pressure, a corresponding 24-hour average TLCPD in microgravity environment was simulated to be 6.7mmHg.Interpretation: We provide a possible physiological explanation for how microgravity can cause symptoms similar to those seen in patients with elevated ICP. The observed posture dependency of TLCPD also implies that assessment of the difference between IOP and ICP in upright position may offer new understanding of the pathophysiology of idiopathic intracranial hypertension and glaucoma.
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| 9. |
- Holmlund, Petter, et al.
(författare)
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Human jugular vein collapse in the upright posture : implications for postural intracranial pressure regulation
- 2017
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Ingår i: Fluids and Barriers of the CNS. - : BioMed Central. - 2045-8118. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- Background: Intracranial pressure (ICP) is directly related to cranial dural venous pressure (P-dural). In the upright posture, P-dural is affected by the collapse of the internal jugular veins (IJVs) but this regulation of the venous pressure has not been fully understood. A potential biomechanical description of this regulation involves a transmission of surrounding atmospheric pressure to the internal venous pressure of the collapsed IJVs. This can be accomplished if hydrostatic effects are cancelled by the viscous losses in these collapsed veins, resulting in specific IJV cross-sectional areas that can be predicted from flow velocity and vessel inclination. Methods: We evaluated this potential mechanism in vivo by comparing predicted area to measured IJV area in healthy subjects. Seventeen healthy volunteers (age 45 +/- 9 years) were examined using ultrasound to assess IJV area and flow velocity. Ultrasound measurements were performed in supine and sitting positions. Results: IJV area was 94.5 mm(2) in supine and decreased to 6.5 +/- 5.1 mm(2) in sitting position, which agreed with the predicted IJV area of 8.7 +/- 5.2 mm(2) (equivalence limit +/- 5 mm(2), one-sided t tests, p = 0.03, 33 IJVs). Conclusions: The agreement between predicted and measured IJV area in sitting supports the occurrence of a hydrostatic-viscous pressure balance in the IJVs, which would result in a constant pressure segment in these collapsed veins, corresponding to a zero transmural pressure. This balance could thus serve as the mechanism by which collapse of the IJVs regulates P-dural and consequently ICP in the upright posture.
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| 10. |
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