1,116 research outputs found
Cotton Flea Hopper, 'Psallus Seriatus' (Reut.) in Oklahoma
The Oklahoma Agricultural Experiment Station periodically issues revisions to its publications. The most current edition is made available. For access to an earlier edition, if available for this title, please contact the Oklahoma State University Library Archives by email at [email protected] or by phone at 405-744-6311
Atmospheric dynamics over Europe during the Younger Dryas revealed by palaeoglaciers
A dataset of 120 palaeoglaciers ranging from Morocco in the south to Svalbard in the north and from Ireland in
the west to Turkey in the east, has been assembled from the literature. A robust quality control on the chronology
was undertaken and, when derived from cosmogenic nuclides, ages were recalculated using the most up-to-date
production rates. All the reconstructed glaciers date to the Younger Dryas. Frontal moraines/limits were used to
initiate the palaeoglacier reconstructions using GlaRe, a GIS tool which generates an equilibrium profile ice surface
along a single flowline and extrapolates this to out to a 3D ice surface. From the resulting glacier surfaces
palaeo-ELAs were calculated within the GIS. Where multiple glaciers were reconstructed within in a region, a
single ELA value was generated. Results show that ELAs decrease with latitude but have a more complex pattern
with longitude. A database of 121 sites, spanning the same geographical range as the palaeoglaciers, was compiled
for Younger Dryas temperature, determined from palaeoproxies, for example pollen, diatoms, coleoptera,
chironimids etc. These proxy data were merged and interpolated to generate maps of average temperature for the
warmest and coldest months and annual average temperature. Results show that, in general, temperature decreases
with latitude. Temperature at the palaeo-ELAs were determined from the temperature maps using a lapse rate of
0.65C/100m and the precipitation required for equilibrium was calculated. Positive precipitation anomalies are
found along much of the western seaboard of Europe, with the most striking positive anomalies present in the
eastern Mediterranean. Negative precipitation anomalies appear on the northern side of the Alps. This pattern is
interpreted to represent a southward displaced polar frontal jet stream with a concomitant track of Atlantic midlatitude depressions, leading to more frequent incursions of low pressure systems especially over the relatively
warm eastern Mediterranean, enhancing cyclogenesis. This is similar to the modern Scandinavia (SCAND) pattern
which, in its positive phase, is characterised by a high pressure anomaly over Fennoscandia and western Russia,
negative pressure anomalies around the Iberian Peninsula and enhanced cyclogenesis in the central and eastern
Mediterranean. During the YD the Fennoscandian Ice Sheet and permafrost across much of northern continental
Europe and Russia would have generated a high pressure region leading to a persistent, enhanced SCAND
circulation
The Local Volume HI Survey: star formation properties
We built a multi-wavelength dataset for galaxies from the Local Volume HI
Survey (LVHIS), which comprises 82 galaxies. We also select a sub-sample of ten
large galaxies for investigating properties in the galactic outskirts. The
LVHIS sample covers nearly four orders of magnitude in stellar mass and two
orders of magnitude in HI mass fraction (fHI). The radial distribution of HI
gas with respect to the stellar disc is correlated with fHI but with a large
scatter. We confirm the previously found correlations between the total HI mass
and star formation rate (SFR), and between HI surface densities and SFR surface
densities beyond R25. However, the former correlation becomes much weaker when
the average surface densities rather than total mass or rate are considered,
and the latter correlation also becomes much weaker when the effect of stellar
mass is removed or controlled. Hence the link between SFR and HI is
intrinsically weak in these regions, consistent with what was found on kpc
scales in the galactic inner regions. We find a strong correlation between the
SFR surface density and the stellar mass surface density, which is consistent
with the star formation models where the gas is in quasi-equilibrium with the
mid-plane pressure. We find no evidence for HI warps to be linked with
decreasing star forming efficiencies.Comment: 31 pages, 20 figures, 4 tables. Accepted for publication at MNRA
Frictional behaviour of three critical geosynthetic interfaces
This paper’s scope is the shear interaction mechanisms of three critical geosynthetic interfaces (geotextile/geomembrane; drainage geocomposite/geomembrane and soil/geomembrane) typically used for lined containment facilities such as landfills. A large direct shear machine was used to carry out 159 geosynthetic interface tests. The results showed strain softening behaviour, a very small dilatancy, 0.1–1 mm, and non-linear failure envelopes at normal stress range of 25–500 kPa. The three types of interfaces present the same main interaction mechanisms: interlocking and friction. For geotextile/geomembrane and drainage geocomposite/geomembrane interfaces, the higher the asperity height, the higher the interface shear strength.Whereas for soil/geomembrane interfaces, the higher the soil shear strength, the higher the interface shear strength. The drainage geocomposite/geomembrane interface showed the lowest friction angles, followed by the geotextile/geomembrane and the soil/geomembrane interfaces
Survival Differences in Pediatric Pulmonary Arterial Hypertension Clues to a Better Understanding of Outcome and Optimal Treatment Strategies
ObjectivesIn order to describe survival and treatment strategies in pediatric pulmonary arterial hypertension (PAH) in the current era of PAH-targeted drugs and to identify predictors of outcome, we studied uniformly defined contemporary patient cohorts at 3 major referral centers for pediatric PAH (New York [NY], Denver, and the Netherlands [NL]).BackgroundIn pediatric PAH, discrepancies exist in reported survival rates between North American and European patient cohorts, and robust data for long-term treatment effects are lacking.MethodsAccording to uniform inclusion criteria, 275 recently diagnosed consecutive pediatric PAH patients who visited the 3 referral centers between 2000 and 2010 were included.ResultsUnadjusted survival rates differed between the center cohorts (1-, 3-, and 5-year transplantation-free survival rates: 100%, 96%, and 90% for NY; 95%, 87%, and 78% for Denver; and 84%, 71%, and 62% for NL, respectively; p < 0.001). Based on World Health Organization (WHO) functional class and hemodynamic parameters, disease severity at diagnosis differed between the center cohorts. Adjustment for diagnosis, WHO functional class, indexed pulmonary vascular resistance, and pulmonary-to-systemic arterial pressure ratio resolved the observed survival differences. Treatment with PAH-targeted dual and triple therapy during the study period was associated with better survival than treatment with PAH-targeted monotherapy.ConclusionsSurvival rates of pediatric PAH patients differed between 3 major referral centers. This could be explained by differences between the center cohorts in patients’ diagnoses and measures of disease severity, which were identified as important predictors of outcome. In this study, treatment with PAH-targeted combination therapy during the study period was independently associated with improved survival
The Role of Bile in the Regulation of Exocrine Pancreatic Secretion
As early as 1926 Mellanby (1) was able to show that introduction of bile into the duodenum of anesthetized cats produces a copious flow of pancreatic juice. In conscious dogs, Ivy & Lueth (2) reported, bile is only a weak stimulant of pancreatic secretion. Diversion of bile from the duodenum, however, did not influence pancreatic volume secretion stimulated by a meal (3,4). Moreover, Thomas & Crider (5) observed that bile not only failed to stimulate the secretion of pancreatic juice but also abolished the pancreatic response to intraduodenally administered peptone or soap
Investigation of the Proteolytic Functions of an Expanded Cercarial Elastase Gene Family in Schistosoma mansoni
Schistosome parasites are a major cause of disease in the developing world. The larval stage of the parasite transitions between an intermediate snail host and a definitive human host in a dramatic fashion, burrowing out of the snail and subsequently penetrating human skin. This process is facilitated by secreted proteases. In Schistosoma mansoni, cercarial elastase is the predominant secreted protease and essential for host skin invasion. Genomic analysis reveals a greatly expanded cercarial elastase gene family in S. mansoni. Despite sequence divergence, SmCE isoforms show similar expression profiles throughout the S. mansoni life cycle and have largely similar substrate specificities, suggesting that the majority of protease isoforms are functionally redundant and therefore their expansion is an example of gene dosage. However, activity-based profiling also indicates that a subset of SmCE isoforms are activated prior to the parasite's exit from its intermediate snail host, suggesting that the protease may also have a role in this process
Onset of the Thermic Effect of Feeding (TEF): a randomized cross-over trial
<p>Abstract</p> <p>Background</p> <p>The purpose of this investigation was to identify the onset of the thermic effect of feeding (TEF) after ingestion of a high carbohydrate (CHO) and a high protein (PRO) 1255 kJ (300 kcal) drink.</p> <p>Methods</p> <p>Resting metabolic rate (RMR) and TEF were measured over 30-minute periods via indirect calorimetry using a ventilated hood technique. Eighteen subjects (7 men and 11 women) completed two randomized, double-blind trials. Data were collected in 1-minute measurement intervals. RMR was subtracted from TEF and the time of onset was obtained when two consecutive data points exceeded 5% and 10% of resting metabolic rate.</p> <p>Results</p> <p>At 5% above RMR the onset of TEF for CHO was 8.4 ± 6.2 minutes and was not different as compared to PRO, 8.6 ± 5.2 minutes (p = 0.77). Likewise, no differences were found with a 10% increase above RMR: CHO, 14.1 ± 7.5 min; PRO, 16.7 ± 6.7 min (p = 0.36). Several subjects did not show a 10% increase within 30-min.</p> <p>Conclusion</p> <p>We conclude that the onset of TEF is variable among subjects but is initiated within about 5 to 20-min for most subjects after ingestion of a 1255 kJ liquid meal. No differences were found between CHO or PRO liquid meals.</p
Chinese-style pragmatic objectivity in war reporting
China plays an increasing role in the wars and conflicts around the world with its expanding political and economic interests overseas, and its diplomatic role in international affairs. More and more Chinese journalists go to the frontlines overseas to cover distant conflicts for domestic audiences. Based on semi-structured in-depth interviews with sixteen Chinese correspondents who have covered conflicts outside China, this study examines Chinese journalists’ perceptions and reflections on objectivity in the war zones. The author adopts a term of Chinese-style pragmatic objectivity to mean that objectivity is a convenient approach for Chinese journalists to do war journalism in the field. At the level of objectivity-as-a- value, objectivity is defined as a pragmatic value and a practical ritual for Chinese journalists to do news within the scope they can reach, to protect themselves from criticisms, and to justify their version of the truth. It promotes allegiance and patriotism. At the level of objectivity-as-a-practice, objectivity in war coverage is compromised by China’s foreign policies, military constraints, the press’s political orientations and editorial polices, and journalists’ personal experiences and values. Chinese journalists use Chinese-style objectivity to negotiate their roles in the power struggle with the state, foreign militaries, the newsroom and journalists
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