Identifying Outflow Regions of North American Monsoon Anticyclone-Mediated Meridional Transport of Convectively Influenced Air Masses in the Lower Stratosphere.

We analyzed the effect of the North American monsoon anticyclone (NAMA) on the meridional transport of summertime cross-tropopause convective outflow by applying a trajectory analysis to a climatology of convective overshooting tops (OTs) identified in GOES satellite images, which covers the domain from 29°S to 68°N and from 205°W to 1.25°W for the time period of May to September, 2013. From this analysis, we identify seasonal development of geographically distinct outflow regions of convectively influenced air masses (CIAMs) from the NAMA circulation to the global stratosphere and quantify the associated meridional displacement of CIAMs. We find that prior to the development of the NAMA, the majority of CIAMs exit the study area in a southeastern region between 5°N and 35°N at 45°W (75.5% in May). During July and August, when the NAMA is strongest, two additional outflow regions develop that constitute the majority of outflow: 68.1% in a northeastern region between 35°N and 60°N at 45°W and 13.4% in a southwestern region between 5°N and 35°N at 145°W. The shift in the location of most CIAM outflow from the pre-NAMA southeastern region to NAMA-dependent northeastern and southwestern regions corresponds to a change in average meridional displacement of CIAMs from 3.3° northward in May to 24.5° northward in July and August. Meridional transport of CIAMs through persistent outflow regions from the NAMA circulation to the global stratosphere has the potential to impact global stratospheric composition beyond convective source regions.

Obesity, dieting, and multiple sclerosis.

BACKGROUND: Obesity is common in the United States and is associated with a higher risk of relapse and comorbidities, and increased disease progression, in people with MS. METHODS: We examined the prevalence of overweight and obesity in the MS Sunshine Study, a matched case-control study of multiple sclerosis in Southern California (470 cases, 519 controls). We reported the proportion of participants who adopted a specific diet for nutrition or weight loss purposes, and identified independent predictors of dieting. RESULTS: In the total population, 32% and 37% were overweight and obese, respectively. Case participants were no more likely to adopt a specific diet for nutrition or weight loss purposes than control participants (10% and 11%, respectively). Being obese, younger, female or non-Hispanic were independently associated with dieting. CONCLUSION: Despite the evidence that obesity can worsen MS prognosis, and the high prevalence of overweight/obesity, case participants were no more likely to adopt a specific diet than control participants. Improved nutrition education may help people with MS make healthy dietary changes for nutrition or weight loss purposes.

Identifying Source Regions and the Distribution of Cross-Tropopause Convective Outflow Over North America During the Warm Season.

We analyzed the interaction between the North American monsoon anticyclone (NAMA) and summertime cross-tropopause convective outflow by applying a trajectory analysis to a climatology of convective overshooting tops (OTs) identified in GOES satellite images, which covers the domain from 29°S to 68°N and from 205 to 1.25°W for the time period of May through September 2013. With this analysis we identified seasonally, geographically, and altitude-dependent variability in NAMA strength and in cross-tropopause convection that control their interaction. We find that the NAMA has the strongest impact on the circulation of convectively influenced air masses in August. Over the entire time period examined the intertropical convergence zone contributes the majority of OTs with a larger fraction of total OTs at 370 K (on average 70%) than at 400 K (on average 52%). During August at 370 K, the convectively influenced air masses within the NAMA circulation, as determined by the trajectory analysis, are primarily sourced from the intertropical convergence zone (monthly average of 66.1%), while at 400 K the Sierra Madres and the Central United States combined constitute the dominant source region (monthly average of 44.1%, compared to 36.6% of the combined Intertropical Convergence Zone regions). When evaluating the impact of cross-tropopause convection on the composition and chemistry of the upper troposphere and lower stratosphere, the effects of the NAMA on both the distribution of convective outflow and the residence time of convectively influenced air masses within the NAMA region must be considered.

Evaluation of UT/LS hygrometer accuracy by intercomparison during the NASA MACPEX mission.

Acquiring accurate measurements of water vapor at the low mixing ratios (< 10 ppm) encountered in the upper troposphere and lower stratosphere (UT/LS) has proven to be a significant analytical challenge evidenced by persistent disagreements between high-precision hygrometers. These disagreements have caused uncertainties in the description of the physical processes controlling dehydration of air in the tropical tropopause layer and entry of water into the stratosphere and have hindered validation of satellite water vapor retrievals. A 2011 airborne intercomparison of a large group of in situ hygrometers onboard the NASA WB-57F high-altitude research aircraft and balloons has provided an excellent opportunity to evaluate progress in the scientific community toward improved measurement agreement. In this work we intercompare the measurements from the Midlatitude Airborne Cirrus Properties Experiment (MACPEX) and discuss the quality of agreement. Differences between values reported by the instruments were reduced in comparison to some prior campaigns but were nonnegligible and on the order of 20% (0.8 ppm). Our analysis suggests that unrecognized errors in the quantification of instrumental background for some or all of the hygrometers are a likely cause. Until these errors are understood, differences at this level will continue to somewhat limit our understanding of cirrus microphysical processes and dehydration in the tropical tropopause layer.

A new direct absorption tunable diode laser spectrometer for high precision measurement of water vapor in the upper troposphere and lower stratosphere.

We present a new instrument for the measurement of water vapor in the upper troposphere and lower stratosphere (UT∕LS), the Harvard Herriott Hygrometer (HHH). HHH employs a tunable diode near-IR laser to measure water vapor via direct absorption in a Herriott cell. The direct absorption technique provides a direct link between the depth of the observed absorption line and the measured water vapor concentration, which is calculated based on spectroscopic parameters in the HITRAN database. While several other tunable diode laser (TDL) instruments have been used to measure water vapor in the UT∕LS, HHH is set apart by its use of an optical cell an order of magnitude smaller than those of other direct absorption TDLs in operation, allowing for a more compact, lightweight instrument. HHH is also unique in its integration into a common duct with the Harvard Lyman-α hygrometer, an independent photo-fragment fluorescence instrument which has been thoroughly validated over 19 years of flight measurements. The instrument was flown for the first time in the Mid-latitude Airborne Cirrus Properties Experiment (MACPEX) on NASA's WB-57 aircraft in spring, 2011, during which it demonstrated in-flight precision of 0.1 ppmv (1 s) with 1-sigma uncertainty of 5% ± 0.7 ppmv. Since the campaign, changes to the instrument have lead to improved accuracy of 5% ± 0.2 ppmv as demonstrated in the laboratory. During MACPEX, HHH successfully measured water vapor at concentrations from 3.5 to 600 ppmv in the upper troposphere and lower stratosphere. HHH and Lyman-α, measuring independently but under the same sampling conditions, agreed on average to within 1% at water vapor mixing ratios above 20 ppmv and to within 0.3 ppmv at lower mixing ratios. HHH also agreed with a number of other in situ water vapor instruments on the WB-57 to within their stated uncertainties, and to within 0.7 ppmv at low water. This agreement constitutes a significant improvement over past in situ comparisons, in which differences of 1.5-2 ppmv were routinely observed, and demonstrates that the accuracy of HHH is consistent with other instruments which use a range of detection methods and sampling techniques.

Acute urinary retention secondary to a urethral calculus in a bladder-drained kidney pancreas transplant patient - a metallic clip nidus.

Urological expertise is usually required for the management of any urological complications of bladder-drained pancreatic allografts whether they are the result of simultaneous pancreas-kidney transplants, pancreas after kidney transplants, or pancreas transplants alone. This study presents a case of urinary retention secondary to prostatic urethra calculus impaction, the nidus of which was found to be metallic staples from the donor duodenal segment of a pancreatic allograft. Knowledge of the pre-transplant benchwork gave a high index of suspicion to the urological sequelae of this case and, in particular, the presence of calculi should suggest a metal clip nidus. We examine the methods of exocrine pancreatic drainage, donor duodenum preparation and case management.

Proximal radial artery ligation after distalization of a high flow brachio-cephalic fistula. A novel approach to inflow reduction.

High flow fistulae present a common challenge to vascular access (VA) surgeons and many strategies have been described, each with their benefits and limitations. There are no NK-DOQI guidelines for the management of high flow fistulae or indeed the management of those refractory to more conventional approaches. We discuss a novel technique to inflow reduction in a previously distalized brachiocephalic fistula and recommend the technique of proximal radial artery ligation.

A new photolysis laser-induced fluorescence instrument for the detection of H2O and HDO in the lower stratosphere.

We present a new instrument, Hoxotope, for the in situ measurement of H(2)O and its heavy deuterium isotopologue (HDO) in the upper troposphere and lower stratosphere aboard the NASA WB-57. Sensitive measurements of deltaD are accomplished through the vacuum UV photolysis of water followed by laser-induced fluorescence detection of the resultant OH and OD photofragments. The photolysis laser-induced fluorescence technique can obtain S/N>20 for 1 ppbv HDO and S/N>30 for 5 ppmv H(2)O for 10 s data, providing the sensitivity required for deltaD measurements in the tropopause region. The technique responds rapidly to changing water concentrations due to its inherently small sampling volume, augmented by steps taken to minimize water uptake on instrument plumbing. Data from the summer 2005 Aura Validation Experiment Water Isotope Intercomparison Flights (AVE-WIIF) out of Houston, TX show agreement for H(2)O between Hoxotope and the Harvard water vapor instrument and for HDO between Hoxotope and the Harvard ICOS water isotope instrument, to within stated instrument uncertainties. The successful intercomparison validates Hoxotope as a credible source of deltaD data in the upper troposphere and lower stratosphere.

National study of physical and sexual assault among women with disabilities.

OBJECTIVE: To examine the association between the level of disability impairment and physical and sexual assault in a sample of US women at least 18 years of age. DESIGN, SETTING AND PARTICIPANTS: Retrospective longitudinal study of 6273 non-institutionalized US women from 8000 women participating in the 1995-1996 National Violence Against Women (NVAW) Survey. MAIN OUTCOME MEASURE: Women's experiences of physical and sexual assault in the 12 months before the NVAW interview. RESULTS: Most women reported having no disability (n = 5008, 79.8%) and/or not experiencing an assault in the year before their interview (n = 6018, 95.9%). Less than 5% (n = 280) reported having a disability that severely limited daily activities, and 15.7% (n = 985) reported having a disability that moderately limited activities. Less than 4% (n = 218) of the women reported a physical-only assault, and less than 1% (n = 37) reported being sexually assaulted. Women with severe disability impairments were four times more likely to be sexually assaulted than women with no reported disabilities (RR = 4.0, 95% CI 1.5 to 10.6). Little difference in the risk of sexual assault was found between women with moderate disability impairments and those reporting no disabilities (RR = 1.0, 95% CI 0.3 to 2.8). Women with severe (RR = 1.6, 95% CI 0.9 to 3.0) and moderate (RR = 1.2, 95% CI 0.8 to 1.9) disability impairments were at greater risk, although not quite significantly so, of physical-only assault than were women without a disability. CONCLUSION: The findings suggest that women with disabilities that severely limit activities of daily living are at increased risk of sexual assault.

A tool for assessing 'readiness' in emergency obstetric care: the room-by-room 'walk-through'.

This article presents a tool that can be used to assess the readiness of a health facility to provide emergency obstetric care. The 'walk-through' tool is a checklist that follows the physical path that a woman and her caregivers might follow. The items on the checklist are critical to an enabling environment in which skilled providers can save lives. The article explains how the tool can be used and by whom, and it describes several experiences in the field.

Multiple separations facilitate identification of protein variants by mass spectrometry.

Identification of variant proteins from complex biological samples promises to contribute much to our understanding the etiology of pathological states. Characterization of variants, either due to genetic mutations in protein sequences or to post-translational modifications, is considerably more difficult than the simple protein identifications typical of most current proteomic investigations. Identification of a few peptides by database retrieval is not adequate when the goal is to have a complete understanding of the modifications of the protein. Although one advantage of mass spectrometry is its ability to obtain specific responses to several components, the complexity of biological samples is often overwhelming, resulting in spectra lacking useful information. For complex mixtures, isolation procedures before mass spectrometric analysis may need to include a variety of chromatographic and electrophoretic separation techniques. In this report, we illustrate how several preparative steps were essential for obtaining information about modified human lens beta-crystallins. The preparative techniques prior to mass spectrometry included size exclusion chromatography, reversed phase chromatography, two-dimensional gel electrophoresis, in situ digestion of the proteins and peptide trapping and washing before a final reversed phase high performance liquid chromatographic separation on-line to the mass spectrometer. This approach for isolation and analysis, when customized for other proteins, should find application in many studies where protein variants of complex mixtures are to be identified.

Resistance of human betaB2-crystallin to in vivo modification.

Post-translational modifications and/or structural changes induced by modifications are likely causes of the decrease in crystallin solubility associated with aging and the development of cataract. Characterization of human lens crystallins by mass spectrometry has demonstrated that betaB2-crystallin undergoes less modification than any of the other crystallins. As the lens ages, betaB2-crystallin retains its hydrophilic N-terminus while the hydrophilic C-termini of alpha-crystallins and large portions of the N-termini of betaA3/A1 and betaB1 are truncated. The hydrophilic terminal regions of crystallins contribute to their solubility. Furthermore, deamidation and disulfide bond formation, other modifications that may affect solubility by altering conformation, are less extensive in betaB2 than in the other crystallins. This resistance to modification results in higher levels of betaB2 compared with the other crystallins in the water-soluble fraction of older lenses. The solubility of betaB2 and its propensity to form non-covalent associations with less soluble beta-crystallins may contribute to the solubility of the other beta-crystallins. A current hypothesis is that the chaperone-like properties of alpha-crystallins contribute to lens crystallin solubility, particularly in younger lenses. In older lenses, where most of the alpha-crystallins have become water-insoluble, betaB2-crystallins may play a dominant role in lens crystallin solubility.

A giant sauropod dinosaur from an Upper Cretaceous mangrove deposit in Egypt.

We describe a giant titanosaurid sauropod dinosaur discovered in coastal deposits in the Upper Cretaceous Bahariya Formation of Egypt, a unit that has produced three Tyrannosaurus-sized theropods and numerous other vertebrate taxa. Paralititan stromeri is the first tetrapod reported from Bahariya since 1935. Its 1.69-meter-long humerus is longer than that of any known Cretaceous sauropod. The autochthonous scavenged skeleton was preserved in mangrove deposits, raising the possibility that titanosaurids and their predators habitually entered such environments.

Estimates of the maternal mortality ratio in two districts of the Brong-Ahafo region, Ghana.

OBJECTIVE: To estimate the maternal mortality ratio (MMR) by the sisterhood method in two districts of the Brong-Ahafo region of Ghana, and to determine the impact of different assumptions and analytical decisions on these estimates. METHODS: Indirect estimates of the MMR were calculated from data collected in 1995 by Family Health International (FHI) on 5202 women aged 15-49 years, using a household screen of randomly selected areas in the two districts. Other data from the nationally representative 1994 Ghana Infant, Child and Maternal Mortality Survey (ICMMS) and from the 1997 Kassena-Nankana District study were also used for comparison. FINDINGS: Based on the FHI data, the MMR was estimated to be 269 maternal deaths per 100,000 live births for both districts combined, a figure higher than ICMMS estimates. Biases during data collection may account for this difference, including the fact that biases underestimating mortality are more common than those overestimating it. Biases introduced during data analysis were also considered, but only the total fertility rate used to calculate the MMR seemed to affect the estimates significantly. CONCLUSIONS: The results indicate that the sisterhood method is still being refined and the extent and impact of biases have only recently received attention. Users of this method should be aware of limitations when interpreting results. We recommend using confidence limits around estimates, both to dispel false impressions of precision and to reduce overinterpretation of data.

Ischemia-reperfusion of rat myocardium activates nuclear factor-KappaB and induces neutrophil infiltration via lipopolysaccharide-induced CXC chemokine.

BACKGROUND: Mechanisms by which neutrophils are attracted to the myocardium in ischemia/reperfusion are not fully defined. Lipopolysaccharide-induced CXC chemokine (LIX), cytokine-induced neutrophil chemoattractant (KC), and macrophage inflammatory protein-2 (MIP-2) are rodent chemokines with potent neutrophil-chemotactic activity. The goals of the present study were to evaluate the roles of these chemokines in a rat model of ischemia/reperfusion and to examine the mechanisms of chemokine induction by oxidative stress and cytokines in cultured cardiomyocytes. METHODS AND RESULTS: Male Wistar-Kyoto rats underwent 45 minutes of ligation of the left anterior descending coronary artery, followed by reperfusion for various periods. Compared with sham-operated controls, myocardium from reperfused animals had higher levels of free radicals, increased neutrophil infiltration evidenced histologically and by elevated myeloperoxidase activity, and increased nuclear factor (NF)-kappaB DNA binding activity. Ischemia-reperfusion also induced the expression of interleukin-1beta, tumor necrosis factor (TNF)-alpha, LIX, KC, and MIP-2 mRNA and protein. LIX expression was localized to resident myocardial cells, whereas KC and MIP-2 were expressed only in infiltrating inflammatory cells. Neutralization of LIX inhibited 79% of neutrophil infiltration into previously ischemic myocardium. In contrast, neutralization of KC and MIP-2 reduced neutrophil infiltration by only 28% and 37%, respectively. In cultured cardiomyocytes, LIX expression was induced by oxidative stress or TNF-alpha and was blocked by the NF-kappaB inhibitor pyrrolidinedithiocarbamate. CONCLUSIONS: LIX is expressed by resident myocardial cells during ischemia-reperfusion and is induced in cultured cardiomyocytes by oxidative stress or TNF-alpha via NF-kappaB activation. Although KC and MIP-2 are expressed by inflammatory cells infiltrating the myocardium during reperfusion after ischemia, neutrophil recruitment to reperfused rat myocardium is mainly due to cardiomyocyte expression of LIX.

In vivo carbamylation and acetylation of water-soluble human lens alphaB-crystallin lysine 92.

Several post-translational modifications of lysine residues of lens proteins have been implicated in cataractogenesis. In the present study, the molecular weight of an alpha-crystallin isolated from the water-soluble portion of a cataractous human eye lens indicated that it was a modified alphaB-crystallin. Further analysis by mass spectrometry of tryptic digests of this modified protein showed that Lys 92 was modified and that the sample was structurally heterogeneous. Lys 92 was acetylated in one population and carbamylated in another. Although carbamylation of lens crystallins has been predicted, this is the first documentation of in vivo carbamylation of a specific site. These results are also the first documentation of in vivo lysine acetylation of alphaB-crystallin. Both modifications alter the net charge on alphaB-crystallin, a feature that may have significance to cataractogenesis.

Using metadata to create navigation paths in the HealthInsite Internet gateway.

The objective of this study was to evaluate the HealthInsite topic query technique, which uses a dynamic database search to assign resources to a topic. It is an alternative to the explicit classification technique, which relies on the classification of each resource using a predefined classification scheme. We performed a recall-precision analysis on all topics within the broad topic area of Child Health. Recall and precision errors were checked to determine which part of the information retrieval process was at fault. We then compared the topic query technique with the explicit classification technique. The results show errors or problems at every stage of the information retrieval process. This has initiated a review of all the tools used in the process, from indexing guidelines to the search engine. While many errors could be corrected, there were still features of the explicit classification technique that could not be achieved by the topic query technique. In conclusion, the topic query technique has the advantage of flexibility, but close co-operation between the different information retrieval specialists is needed to get the best results. The HealthInsite topic navigation structure should be regarded as an organized set of predefined searches rather than a full classified listing.

Potentiation of thromboxane A2-induced platelet secretion by Gi signaling through the phosphoinositide-3 kinase pathway.

Platelet activation results in shape change, aggregation, generation of thromboxane A2, and release of granule contents. We have recently demonstrated that secreted ADP is essential for thromboxane A2-induced platelet aggregation (J. Biol. Chem. 274: 29108-29114, 1999). The aim of this study was to investigate the role of secreted ADP interacting at P2 receptor subtypes in platelet secretion. Platelet secretion induced by the thromboxane A2 mimetic U46619 was unaffected by adenosine-3'phosphate-5'-phosphate, a P2Y1 receptor selective antagonist. However, AR-C66096, a selective antagonist of the P2T(AC) receptor, inhibited U46619-induced platelet secretion, indicating an important role for Gi signaling in platelet secretion. Selective activation of either the P2T(AC) receptor or the alpha2A adrenergic receptor did not cause platelet secretion, but potentiated U46619-induced platelet secretion. SC57101, a fibrinogen receptor antagonist, failed to inhibit platelet secretion, demonstrating that outside-in signaling was not required for platelet secretion. Since Gi signaling results in reduction of basal cAMP levels through inhibition of adenylyl cyclase, we investigated whether this is the signaling event that potentiates platelet secretion. SQ22536 or dideoxyadenosine, inhibitors of adenylyl cyclase, failed to potentiate U46619-induced primary platelet secretion, indicating that reduction in cAMP levels does not directly contribute to platelet secretion. Wortmannin, a selective inhibitor of PI-3 kinase, minimally inhibited U46619-induced platelet secretion when it was solely mediated by Gq, but dramatically ablated the potentiation of Gi signaling. We conclude that signaling through the P2T(AC) receptor by secreted ADP causes positive feedback on platelet secretion through a PI-3 kinase pathway.