Approximately 50% of fatal and 15% of nonfatal burn-injured patients have detectable blood alcohol content (BAC) at the time of admission, and it is hypothesized that alcohol exacerbates burn-related ...immunosuppression. The purpose of this study was to evaluate the association between BAC and infectious complications in burn patients. The study population consisted of 1161 burn patients admitted to a large academic burn center between January 1998 and June 2007. Patients were categorized into no BAC (0.0 g/100 ml), low/moderate BAC (>0.0 and <0.1 g/100 ml) and high BAC (> or =0.1 g/100 ml) groups based on BAC at time of admission. Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated for associations between pneumonia, sepsis, urinary tract infection, line infection, and wound infection and BAC, adjusted for total burn surface area and inhalation injury. Relative to no BAC patients, both low/moderate and high BAC patients had nonsignificantly increased risk for most infectious complications. High BAC patients were at significantly increased risk for any infectious complication (RR 2.06, CI 1.25-3.41) and pneumonia (RR 2.06, CI 1.04-4.09) and a nonsignificantly increased risk of urinary tract infection (RR 2.12, CI 0.0.94-4.78). Results suggest that preinjury alcohol consumption places patients at an increased risk for infectious complications, most notably pneumonia. Further studies examining the relationship between alcohol and pneumonia among burn patients will help elucidate the reason for the increased risk observed in the current study and suggest ways to prevent infection for this particular subgroup of burn patients.
Both satellite water vapor measurements and in situ aircraft measurements indicate that the southern hemisphere lower stratosphere is drier than that of the northern hemisphere in an annual average ...sense. This is the result of a combination of factors. At latitudes poleward of ∼50°S, dehydration in the Antarctic polar vortex lowers water vapor mixing ratios relative to those in the north during late winter and spring. Equatorward of ∼50°S, water vapor in the lower stratosphere is largely controlled by the tropical seasonal cycle in water vapor coupled with the seasonal cycle in extratropical descent. During the tropical moist period (June, July, and August), air ascending in the Indian monsoon region influences the northern hemisphere more than the southern hemisphere, resulting in a moister northern hemisphere lower stratosphere. This tropical influence is confined to levels beneath 60 mbar at low latitudes, and beneath 90 mbar at high latitudes. During the tropical dry period (December, January, and February), dry air spreads initially into both hemispheres. However, the stronger northern hemisphere wintertime descent that exists relative to that of southern hemisphere summer transports the dry air out of the northern hemisphere lower stratosphere more quickly than in the south. This same hemispheric asymmetry in winter descent (greater descent rates during northern hemisphere winter than during southern hemisphere winter) brings down a greater quantity of “older” higher water vapor content air in the north, which also acts to moisten the northern hemisphere lower stratosphere relative to the southern hemisphere. These factors all act together to produce a drier southern hemisphere lower stratosphere as compared to that in the north. The overall picture that comes from this study in regards to transport characteristics is that the stratosphere can be divided into three regions. These are (1) the “overworld” where mass transport is controlled by nonlocal dynamical processes, (2) the “tropically controlled transition region” made up of relatively young air that has passed through (and been dehydrated by) the cold tropical tropopause, and (3) the stratospheric part of the “middleworld” or “lowermost stratosphere”, where troposphere‐stratosphere exchange can occur adiabatically. Satellite water vapor measurements indicate that the base of the “overworld” is near 60 mbar in the tropics, or near the 450 K isentropic surface.
•The type of vegetation influences the distribution of brGDGTs in soils.•New calibrations have been developed for soils with vegetation.•These temperature calibrations more closely reflect actual ...temperatures.•The newly calibrated LGM temperature reconstruction is consistent with other records.•Our calibrations enhance precision of temperature reconstruction during the past.
Distributions of branched glycerol dialkyl glycerol tetraether (brGDGT) lipids are sensitive to environmental parameters, which enables their use in paleoenvironmental studies. In particular, the degree of methylation of brGDGTs (MBT and MBT′) and the cyclization ratio of brGDGTs (CBT) are often used to estimate changes in temperature in paleoclimate studies. Application of these proxies requires reliable and precise calibrations to temperature. However, available calibrations of brGDGT proxies to temperature have large calibration errors in arid areas which suggests that other environmental variables influence brGDGT distributions in these areas. Here we analyze brGDGT distributions in soils from the Tibetan Plateau, an arid/semi-arid region with gradients in vegetation cover (forest, grassland, and desert) to examine: (1) the applicability of MBT′/CBT calibrations to reconstruct mean annual air temperature (MAAT); and (2) the effects of vegetation cover on temperature calibrations. We show that temperatures reconstructed using the global soil MBT′/CBT calibrations are warmer than instrumentally observed temperature, and that the calibrations are significantly influenced by the presence or absence of vegetation. Excluding sample sites without vegetation (bare soil) from temperature calibrations substantially improves the correlation between observed and reconstructed temperatures. Within the vegetated soils, we reanalyzed published global soil calibration datasets, including results of analyses that either did or did not separate 5- and 6-methyl brGDGT isomers, and find that the correlation between MBT′5Me and MBT′ and temperature varies for different vegetation types (grass and forest) and that the error of temperature calibrations is reduced if calibrations are separated by the type of vegetative cover (grass or forest). We test these new calibrations in sequences from the Lantian and Mangshan loess of the Chinese Loess Plateau and find that reconstructed temperatures from both modern and Last Glacial Maximum sediments are more consistent with other reconstructions and climate model simulations when vegetation-specific calibrations are applied to the brGDGT data. The results indicate that changes in vegetation should be taken into consideration when applying brGDGT proxies to reconstruct past changes in climate.
Severe stratospheric ozone depletion is the result of perturbations of chlorine chemistry owing to the presence of polar stratospheric clouds (PSCs) during periods of limited exchange of air between ...the polar vortex and midlatitudes and partial exposure of the vortex to sunlight. These conditions are consistently encountered over Antarctica during the austral spring. In the Arctic, extensive PSC formation occurs only during the coldest winters, when temperatures fall as low as those regularly found in the Antarctic,,. Moreover, ozone levels in late winter and early spring are significantly higher than in the corresponding austral season,,, and usually strongly perturbed by atmospheric dynamics. For these reasons, chemical ozone loss in the Arctic is difficult to quantify. Here we use the correlation between CH4 and O3 in the Arctic polar vortex to discriminate between changes in ozone concentration due to chemical and dynamical effects. Our results indicate that 120-160 Dobson units (DU) of ozone were chemically destroyed between January and March 1996-a loss greater than observed in Antarctica in 1985, when the 'ozone hole' was first reported,. This loss outweighs the expected increase in total ozone over the same period through dynamical effects, leading to an observed net decrease of about 50 DU. This ozone loss arises through the simultaneous occurrence of extremely low Arctic stratospheric temperatures, and large stratospheric chlorine loadings. Comparable depletion is likely to recur because stratospheric cooling, and elevated chlorine concentrations, are expected to persist for several decades.
The American Heart Association and the American Stroke Association recommend intravenous (IV) thrombolysis up to 4.5 h from acute ischemic stroke symptom onset based on its proven benefit in ...improving patient outcomes. We analyzed data from the Minnesota Stroke Registry to assess the rates of IV thrombolytic utilization and the process of care in this expanded window.
We identified patients who had received IV recombinant tissue plasminogen activator (rt-PA) at any of the 19 participating hospitals from January 1, 2008 till December 31, 2010. Treatment groups were those actually treated by IV rt-PA in 0-3 h and those treated by IV rt-PA in 3-4.5 h. Duration from symptom onset to arrival in the emergency department (ED) was dichotomized to cohorts of 0-2 and 2-3.5 h. We determined the overall utilization of IV rt-PA in the expanded window and calculated door-to-needle times for the two treatment windows. We also ascertained the rates of symptomatic intracerebral hemorrhage between the two treatment groups.
Out of the total 519 patients who received IV rt-PA for acute ischemic stroke, 433 (83%) were treated within 0-3 h and 86 (17%) within 3-4.5 h. Of all the patients who received IV rt-PA within 3-4.5 h, 45% arrived at the ED within 2 h of symptom onset. Median door-to-needle time for the 0- to 3-hour window was 74.5 min interquartile range (IQR) 57-90 and 54 min (IQR 43.5-70.5) for the 3- to 4.5-hour window. Based on arrival time to the ED, door-to-needle time of ≤60 min was achieved by only 31% (142/458) of patients who arrived within 0-2 h of their symptom onset compared to 61% (37/61) of those who arrived at the ED within 2-3.5 h of their symptom onset. Fifty-nine (14%) patients in the 0- to 3-hour group and 17 (20%) patients in the 3- to 4.5-hour group received a combination of IV rt-PA and endovascular treatments. Among patients with documented admission National Institutes of Health Stroke Scale scores, the values (median with IQR) were different between the 0- to 3- and the 3- to 4.5-hour group, i.e. 10 (IQR 5-18) and 7 (IQR 4-14), respectively.
Patients who received IV rt-PA within the 3- to 4.5-hour window comprised 17% of all IV rt-PA cases treated in the Minnesota Stroke Registry hospitals after the new guidelines recommended a time window expansion. Almost half of these patients would have qualified for treatment within the 0- to 3-hour window as they presented within 0-2 h of symptom onset. Patients arriving 2-3.5 h after symptom onset received thrombolysis on average 20 min faster than patients arriving within 2 h of symptom onset.
The Cloud Imaging and Particle Size (CIPS) instrument on the Aeronomy of Ice in the Mesosphere (AIM) satellite provides an opportunity to study the longitudinal variation in polar mesospheric cloud ...(PMC). We examined the longitudinal variation in PMC albedo using 8 years (2007–2014) of observations from the CIPS instrument. The results show that the PMC albedo in the Southern Hemisphere (SH), especially in the latitude band of 80°S–85°S, is persistently low (~65% relative to the rest of the hemisphere) within 60°W to 150°W longitude. In the Northern Hemisphere (NH), however, PMC albedo is found to be relatively zonally asymmetry. Harmonic analyses show that the persistent longitudinal variation in the SH PMC albedo is due to zonal wave numbers 1 through 4 (WN1–WN4) processes with minima in the longitude range of 60°W–150°W. The influence of temperature and H2O on the longitudinal variation of the PMC albedo is discussed based on results obtained using a simple 0‐D PMC model and temperature from the Microwave Limb Sounder (MLS) and the Sounding of the Atmosphere with Broadband Emission Radiometry (SABER) and H2O from MLS. The modeled region of low ice mass in the SH is generally consistent with that of low PMC albedo seen in CIPS. Tidal analyses using the SABER temperatures indicate that the nonmigrating semidiurnal tides with modes of S0, W1, and E1 might be the main drivers of the persistent longitudinal variations of PMC albedo in the SH. Nonmigrating tides are much weaker in the NH and consistent with the observed lack of longitudinal variability in PMC albedo.
Key Points
Persistent weak PMC albedo was found in 60°W–150°W of the SH but not in the NH
Weak PMC coincides with higher T from MLS and lower modeled ice density
Weak PMC coincides with warm phases of strong nonmigrating 12 h tides from SABER
Glycerol monoalkyl glycerol tetraethers (GMGTs) are a group of membrane spanning lipids produced by some species of archaea and bacteria. They differ from the more commonly studied glycerol dialkyl ...glycerol tetraethers (GDGTs) in having an additional covalent carbon-carbon bond connecting the two alkyl chain. The relative abundance and distribution of bacterial branched GMGTs (brGMGTs) in surface sediments from a set of East African lakes were studied. The abundance of brGMGTs relative to the brGDGTs is positively correlated to measured mean annual air temperature (MAAT), although with a significant amount of scatter. BrGMGT abundance was not correlated to lake water pH. Seven major brGMGTs that vary in degree of methylation were identified, with m/z 1020, 1034 and 1048. Further, the mass chromatograms of the m/z 1020 and 1034 brGMGTs show an interesting distribution of peaks, which likely relates to the occurrence of distinct brGMGT isomers. This structural complexity is higher than previously observed in peats and marine sediments. Principal component analysis of the fractional abundance of bacterial tetraether lipids revealed the brGMGTs behave similarly to one another but differently from both the 5- or 6-methyl brGDGTs. This suggests the brGMGTs are produced by a common source organism and are methylated at a different position. The distribution of the seven brGMGTs showed considerable correlation with MAAT. This variability was captured in a new proxy index (the brGMGTI), which showed a strong positive linear relationship with MAAT. Lacustrine brGMGTs show potential to be applied to ancient settings to provide information about paleoclimate.
ABSTRACT
Objective: To examine the relationship between global functional impairment and the treatment of anxious symptoms and painful somatic symptoms (PSS) in patients with generalized anxiety ...disorder (GAD).
Research design and methods: Data from two double-blind, placebo-controlled trials in adult outpatients meeting DSM-IV criteria for GAD were pooled. In the first trial (9-week, fixed-dose treatment period), patients were randomized to duloxetine 60 mg QD (n = 168), duloxetine 120 mg QD (n = 170), or placebo (n = 175). In the second trial (10-week, flexible-dose treatment period), patients were randomized to 60-120 mg QD of duloxetine (n = 168) or placebo (n = 159). Path analysis was used to assess the relative contributions of changes in psychic and somatic anxiety and PSS on improved functional outcomes. Clinical trial registration information: Study 1: NCT00122824; Study 2: study completed before registration required.
Main outcome measures: Sheehan Disability Scale (SDS), Hamilton Anxiety Rating Scale (HAMA), and Visual Analog Scale for overall pain (VAS).
Results: There was a moderate correlation (0.45, p < 0.05) at endpoint between changes in global functional impairment and changes in psychic anxiety (controlling for somatic anxiety and PSS); whereas the correlation between changes in global functional impairment and changes in somatic anxiety (controlling for psychic anxiety and PSS) was weak (0.09, p < 0.05). The correlation between changes in global functional impairment and changes in PSS (controlling for psychic and somatic anxiety) was weak (0.27, p < 0.05). Path analysis revealed that 37% of the total improvement in functional impairment (Sheehan Disability Scale total score) due to duloxetine treatment was independent of improvement in the Hamilton Anxiety Rating Scale (HAMA) psychic and somatic anxiety subscale scores or Visual Analog Scale for overall pain (VAS) score. Improvement in psychic anxiety accounted for 47% of the total treatment effect on improvement of functional impairment, whereas 7% and 9% of the improvement in functional impairment was accounted for by improvements in somatic anxiety and overall pain, respectively.
Limitations: This was a post-hoc exploratory analysis. Patients with co-morbid Major Depressive Disorder (MDD) or significant depressive symptoms were excluded from these GAD studies.
Conclusions: In patients with GAD, there was a moderate correlation between improvement in psychic anxiety symptoms and improvement in global functional impairment, whereas the correlation between improvements in somatic anxiety or PSS and improvement in global functional impairment was low. Most of the treatment effect of duloxetine in improvement of functional impairment was mediated through improvement in psychic anxiety, with smaller contributions through improvement in somatic anxiety and PSS. Some of the improvement in functional impairment for duloxetine-treated patients was independent of improvement through any of these domains.
The World Heritage Convention could make a bigger and more systematic contribution to global wilderness conservation by: (1) ensuring the World Heritage List includes full coverage of Earth's ...wilderness areas with outstanding universal value and (2) more effectively protecting the ecological integrity of existing World Heritage sites. Here, we assess current coverage of globalâscale wilderness areas within natural World Heritage sites and identify broad gaps where new wilderness sites should be identified for inclusion in the World Heritage List. We also consider how existing mechanisms under the Convention can improve the ecological integrity of existing sites by expanding or buffering them, and by promoting connectivity between World Heritage sites, between World Heritage sites and other protected areas, or both. We suggest that the Convention should consider a new mechanism called a âWorld Heritage Wilderness Complexâ to facilitate a wilderness approach. Finally, we map three landscapes and one seascape to illustrate how World Heritage Wilderness Complexes might be implemented.