Northern hemispheric winter warming pattern after tropical volcanic eruptions: Sensitivity to the ozone climatology

An important key for the understanding of the dynamic response to large tropical volcanic eruptions is the warming of the tropical lower stratosphere and the concomitant intensification of the polar vortices. Although this mechanism is reproduced by most general circulation models today, most models still fail in producing an appropriate winter warming pattern in the Northern Hemisphere. In this study ensemble sensitivity experiments were carried out with a coupled atmosphere-ocean model to assess the influence of different ozone climatologies on the atmospheric dynamics and in particular on the northern hemispheric winter warming. The ensemble experiments were perturbed by a single Tambora-like eruption. Larger meridional gradients in the lower stratospheric ozone favor the coupling of zonal wind anomalies between the stratosphere and the troposphere after the eruption. The associated sea level pressure, temperature, and precipitation patterns are more pronounced and the northern hemispheric winter warming is highly significant. Conversely, weaker meridional ozone gradients lead to a weaker response of the winter warming and the associated patterns. The differences in the number of stratosphere-troposphere coupling events between the ensembles experiments indicate a nonlinear response behavior of the dynamics with respect to the ozone and the volcanic forcing.

Neurogranin controls the spatiotemporal pattern of postsynaptic Ca2+/CaM signaling.

Neurogranin (Ng) is a postsynaptic IQ-motif containing protein that accelerates Ca(2+) dissociation from calmodulin (CaM), a key regulator of long-term potentiation and long-term depression in CA1 pyramidal neurons. The exact physiological role of Ng, however, remains controversial. Two genetic knockout studies of Ng showed opposite outcomes in terms of the induction of synaptic plasticity. To understand its function, we test the hypothesis that Ng could regulate the spatial range of action of Ca(2+)/CaM based on its ability to accelerate the dissociation of Ca(2+) from CaM. Using a mathematical model constructed on the known biochemistry of Ng, we calculate the cycle time that CaM molecules alternate between the fully Ca(2+) saturated state and the Ca(2+) unbound state. We then use these results and include diffusion of CaM to illustrate the impact that Ng has on modulating the spatial profile of Ca(2+)-saturated CaM within a model spine compartment. Finally, the first-passage time of CaM to transition from the Ca(2+)-free state to the Ca(2+)-saturated state was calculated with or without Ng present. These analyses suggest that Ng regulates the encounter rate between Ca(2+) saturated CaM and its downstream targets during postsynaptic Ca(2+) transients.

Is there a common pattern of future gas-phase air pollution in Europe under diverse climate change scenarios?

Climate change alone influences future levels of tropospheric ozone and their precursors through modifications of gas-phase chemistry, transport, removal, and natural emissions. The goal of this study is to determine at what extent the modes of variability of gas-phase pollutants respond to different climate change scenarios over Europe. The methodology includes the use of the regional modeling system MM5 (regional climate model version)-CHIMERE for a target domain covering Europe. Two full-transient simulations covering from 1991–2050 under the SRES A2 and B2 scenarios driven by ECHO-G global circulation model have been compared. The results indicate that the spatial patterns of variability for tropospheric ozone are similar for both scenarios, but the magnitude of the change signal significantly differs for A2 and B2. The 1991–2050 simulations share common characteristics for their chemical behavior. As observed from the NO2 and α-pinene modes of variability, our simulations suggest that the enhanced ozone chemical activity is driven by a number of parameters, such as the warming-induced increase in biogenic emissions and, to a lesser extent, by the variation in nitrogen dioxide levels. For gas-phase pollutants, the general increasing trend for ozone found under A2 and B2 forcing is due to a multiplicity of climate factors, such as increased temperature, decreased wet removal associated with an overall decrease of precipitation in southern Europe, increased photolysis of primary and secondary pollutants as a consequence of lower cloudiness and increased biogenic emissions fueled by higher temperatures.

Intron involvement in the regulation of MuSVts110 RNA splicing

The murine sarcoma virus MuSVts110 exhibits an alternative RNA splicing pattern. Like other simple retroviruses, MuSVts110 pre-mRNA splicing is balanced to allow the production of both spliced and unspliced RNA during the replicative cycle. In addition to balance, MuSVts110 RNA splicing exhibits a unique growth-temperature restriction to splicing; temperatures below 33$\sp\circ$C are permissive for splicing while temperatures of 37$\sp\circ$C or above are non-permissive. Previous work has established that this thermosensitive splicing phenotype is mediated in cis by viral transcript features. Here we show that at least three sequence elements regulate the MuSVts110 splicing phenotype. First, the MuSVts110 branchpoint (BP) and poly-pyrimidine tract (PPT) were found to be determinants of overall splicing efficiency. Wild-type MuSVts110 possesses a weak BP and PPT adjacent to the 3$\sp\prime$ splice site. Introduction of a strong BP caused MuSVts110 splicing to proceed to virtual completion in vivo, thus losing any vestige of balance or thermosensitivity. In in vitro splicing extracts, the strong BP overcame a blockade to wt MuSVts110 splicing at both the first and second catalytic steps. Weakening the consensus nature of the strong BP allowed the recovery of thermosensitive splicing in vivo, and reinstated the blockades to splicing in vitro, arguing that a suboptimal BP is an unusual manifestation of the proportional splicing pattern of retroviruses. The PPT is essential for accurate recognition of the BP sequence by the splicing machinery. Lengthening the PPT of MuSVts110 from 9 to 19 consecutive pyrimidines increased the overall efficiency of splicing in vivo dramatically, but was less effective than the strong BP in overriding the restriction on splicing imposed by high growth temperatures. Finally, decreasing gradually the overall size of the intron unexpectedly reduced splicing efficiency at growth temperatures permissive for splicing, suggesting that non-conserved sequences within the intron of MuSVts110 participate in splicing regulation as well. Taken together, these results suggest a mechanism of control in which MuSVts110 splicing is modulated by the entire intron, but principally by suboptimal signals at the splice acceptor site. Furthermore, this retroviral system provides a powerful genetic method for selection and analysis of mutations that affect splicing. ^

An examination of the rate of high school completion experienced by handicapped and nonhandicapped students in the state of Texas

This research examines the graduation rate experienced by students receiving public education services in the state of Texas. Special attention is paid to that subgroup of Texas students who meet Texas Education Agency criteria for handicapped status. The study is guided by two research questions: What are the high school completion rates experienced by handicapped and nonhandicapped students attending Texas public schools? and What are the predictors of graduation for handicapped and nonhandicapped students?^ In addition, the following hypotheses are explored. Hypothesis 1: Handicapped students attending a Texas public school will experience a lower rate of high school completion than their nonhandicapped counterparts. Hypothesis 2: Handicapped and nonhandicapped students attending school in a Texas public school with a budget above the median budget for Texas public schools will experience a higher rate of high school completion than similar students in Texas public schools with a budget below the median budget. Hypothesis 3: Handicapped and nonhandicapped students attending school in large Texas urban areas will experience a lower rate of high school completion than similar students in Texas public schools in rural areas. Hypothesis 4: Handicapped and nonhandicapped students attending a Texas public school in a county which rates above the state median for food stamps and AFDC recipients will experience a lower rate of high school completion than students living in counties below the median.^ The study will employ extant data from the records of the Texas Education Agency for the 1988-1989 and the 1989-1990 school years, from the Texas Department of Health for the years of 1989 and 1990, and from the 1980 Census.^ The study reveals that nonhandicapped students are graduating with a two year average rate of.906, while handicapped students following an Individualized Educational Program (IEP) achieve a two year average rate of.532, and handicapped students following the regular academic program present a two year average graduation rate of only.371. The presence of other handicapped students, and the school district's average expense per student are found to contribute significantly to the completion rates of handicapped students. Size groupings are used to elucidate the various impacts of these variables on different school districts and different student groups.^ Conclusions and implications are offered regarding the need to reach national consensus on the definition and computation of high school completion for both handicapped and nonhandicapped students, and the need for improved statewide tracking of handicapped completion rates. ^

ICESat Measurements Reveal Complex Pattern of Elevation Changes on Siple Coast Ice Streams, Antarctica

We compare ICESat data (2003-2004) to airborne laser altimetry data (1997-98 and 1999-2000) to monitor surface changes over portions of Van der Veen (VdVIS), Whillans (WIS) and Kamb ice streams (KIS) in the Ross Embayment of the West Antarctic Ice Sheet. The spatial pattern of detected surface changes is generally consistent with earlier observations. However, important changes have occurred during the past decade. For example, areas on the VdVIS and WIS, where large thinning was detected by the airborne surveys, are now closer to being in balance. The upper trunk of KIS continues to build up with thickening rates reaching 0.4 m/year. Our results provide new evidence that the overall mass balance of the region is becoming more positive, but a significant spatial variability exists. They also demonstrate the potential of ICESat data for detecting spatial patterns of surface elevation change in Antarctica.

Unconscious word stem completion priming in a mirror-masking paradigm

The aim of this study was to investigate unconscious priming by the use of a spatial mirror-masking paradigm. Words and nonwords with no under-length letters are mirrored at their horizontal axis. The results are figures of geometric-like forms that contain letters in their upper part. In the three experiments reported in this study, a priming procedure used such mirrored words and nonwords as primes. Participants were ignorant of the nature of the construction of the stimuli. Perceptual reports of the participants revealed that they did not realize that words were hidden in the primes. Nevertheless, they showed priming in all three experiments. Priming effects were replicated with prime–target SOAs of between 1 and 3 s. Functional dissociations were found between ignorant and informed participants. Informed groups showed perceptual and semantic priming, while ignorant groups showed only perceptual priming.

Effects of Thoratec pulsatile ventricular assist device (PVAD) timing on the abdominal aortic wave intensity pattern

Arterial waves are seen as possible independent mediators of cardiovascular risks, and the wave intensity analysis (WIA) has therefore been proposed as a method for patient selection for ventricular assist device (VAD) implantation. Interpreting measured wave intensity (WI) is challenging and complexity is increased by the implantation of a VAD. The waves generated by the VAD interact with the waves generated by the native heart, and this interaction varies with changing VAD settings. Eight sheep were implanted with a pulsatile VAD (PVAD) through ventriculo-aortic cannulation. The start of PVAD ejection was synchronized to the native R-wave and delayed between 0 % - 90 % of the cardiac cycle in 10 % steps or phase shifts (PS). Pressure and velocity signals were registered, using a combined Doppler and pressure wire positioned in the abdominal aorta, and used to calculate the WI. Depending on the PS, different wave interference phenomena occurred. Maximum unloading of the left ventricle (LV) coincided with constructive interference and maximum blood flow pulsatility, and maximum loading of the LV coincided with destructive interference and minimum blood flow pulsatility. We believe, that non-invasive WIA could potentially be used clinically to assess the mechanical load of the LV, and to monitor the peripheral hemodynamics such as blood flow pulsatility and risk of intestinal bleeding.

Influence of hormone replacement therapy on proteomic pattern in serum of postmenopausal women

OBJECTIVES: Proteomics approaches to cardiovascular biology and disease hold the promise of identifying specific proteins and peptides or modification thereof to assist in the identification of novel biomarkers. METHOD: By using surface-enhanced laser desorption and ionization time of flight mass spectroscopy (SELDI-TOF-MS) serum peptide and protein patterns were detected enabling to discriminate between postmenopausal women with and without hormone replacement therapy (HRT). RESULTS: Serum of 13 HRT and 27 control subjects was analyzed and 42 peptides and proteins could be tentatively identified based on their molecular weight and binding characteristics on the chip surface. By using decision tree-based Biomarker Patternstrade mark Software classification and regression analysis a discriminatory function was developed allowing to distinguish between HRT women and controls correctly and, thus, yielding a sensitivity of 100% and a specificity of 100%. The results show that peptide and protein patterns have the potential to deliver novel biomarkers as well as pinpointing targets for improved treatment. The biomarkers obtained represent a promising tool to discriminate between HRT users and non-users. CONCLUSION: According to a tentative identification of the markers by their molecular weight and binding characteristics, most of them appear to be part of the inflammation induced acute-phase response

Early co-occurrence of a neurologic-psychiatric disease pattern in Niemann-Pick type C disease: a retrospective Swiss cohort study

BackgroundNiemann-Pick disease type C (NP-C) is a rare autosomal recessive disorder of lysosomal cholesterol transport. The objective of this retrospective cohort study was to critically analyze the onset and time course of symptoms, and the clinical diagnostic work-up in the Swiss NP-C cohort.MethodsClinical, biochemical and genetic data were assessed for 14 patients derived from 9 families diagnosed with NP-C between 1994 and 2013. We retrospectively evaluated diagnostic delays and period prevalence rates for neurological, psychiatric and visceral symptoms associated with NP-C disease. The NP-C suspicion index was calculated for the time of neurological disease onset and the time of diagnosis.ResultsThe shortest median diagnostic delay was noted for vertical supranuclear gaze palsy (2y). Ataxia, dysarthria, dysphagia, spasticity, cataplexy, seizures and cognitive decline displayed similar median diagnostic delays (4¿5y). The longest median diagnostic delay was associated with hepatosplenomegaly (15y). Highest period prevalence rates were noted for ataxia, dysarthria, vertical supranuclear gaze palsy and cognitive decline. The NP-C suspicion index revealed a median score of 81 points in nine patients at the time of neurological disease onset which is highly suspicious for NP-C disease. At the time of diagnosis, the score increased to 206 points.ConclusionA neurologic-psychiatric disease pattern represents the most characteristic clinical manifestation of NP-C and occurs early in the disease course. Visceral manifestation such as isolated hepatosplenomegaly often fails recognition and thus highlights the importance of a work-up for lysosomal storage disorders. The NP-C suspicion index emphasizes the importance of a multisystem evaluation, but seems to be weak in monosymptomatic and infantile NP-C patients.

Comparison of energy expenditure, eating pattern and physical activity of grazing and zero-grazing dairy cows at different time points during lactation

An experiment was conducted to determine the effect of grazing versus zero-grazing on energy expenditure (EE), feeding behaviour and physical activity in dairy cows at different stages of lactation. Fourteen Holstein cows were subjected to two treatments in a repeated crossover design with three experimental series (S1, S2, and S3) reflecting increased days in milk (DIM). At the beginning of each series, cows were on average at 38, 94 and 171 (standard deviation (SD) 10.8) DIM, respectively. Each series consisted of two periods containing a 7-d adaptation and a 7-d collection period each. Cows either grazed on pasture for 16–18.5 h per day or were kept in a freestall barn and had ad libitum access to herbage harvested from the same paddock. Herbage intake was estimated using the double alkane technique. On each day of the collection period, EE of one cow in the barn and of one cow on pasture was determined for 6 h by using the 13C bicarbonate dilution technique, with blood sample collection done either manually in the barn or using an automatic sampling system on pasture. Furthermore, during each collection period physical activity and feeding behaviour of cows were recorded over 3 d using pedometers and behaviour recorders. Milk yield decreased with increasing DIM (P<0.001) but was similar with both treatments. Herbage intake was lower (P<0.01) for grazing cows (16.8 kg dry matter (DM)/d) compared to zero-grazing cows (18.9 kg DM/d). The lowest (P<0.001) intake was observed in S1 and similar intakes were observed in S2 and S3. Within the 6-h measurement period, grazing cows expended 19% more (P<0.001) energy (319 versus 269 kJ/kg metabolic body size (BW0.75)) than zero-grazing cows and differences in EE did not change with increasing DIM. Grazing cows spent proportionally more (P<0.001) time walking and less time standing (P<0.001) and lying (P<0.05) than zero-grazing cows. The proportion of time spent eating was greater (P<0.001) and that of time spent ruminating was lower (P<0.05) for grazing cows compared to zero-grazing cows. In conclusion, lower feed intake along with the unchanged milk production indicates that grazing cows mobilized body reserves to cover additional energy requirements which were at least partly caused by more physical activity. However, changes in cows׳ behaviour between the considered time points during lactation were too small so that differences in EE remained similar between treatments with increasing DIM.

Completion and Publication Rates of Randomized Controlled Trials in Surgery: An Empirical Study.

OBJECTIVE: To investigate the prevalence of discontinuation and nonpublication of surgical versus medical randomized controlled trials (RCTs) and to explore risk factors for discontinuation and nonpublication of surgical RCTs. BACKGROUND: Trial discontinuation has significant scientific, ethical, and economic implications. To date, the prevalence of discontinuation of surgical RCTs is unknown. METHODS: All RCT protocols approved between 2000 and 2003 by 6 ethics committees in Canada, Germany, and Switzerland were screened. Baseline characteristics were collected and, if published, full reports retrieved. Risk factors for early discontinuation for slow recruitment and nonpublication were explored using multivariable logistic regression analyses. RESULTS: In total, 863 RCT protocols involving adult patients were identified, 127 in surgery (15%) and 736 in medicine (85%). Surgical trials were discontinued for any reason more often than medical trials [43% vs 27%, risk difference 16% (95% confidence interval [CI]: 5%-26%); P = 0.001] and more often discontinued for slow recruitment [18% vs 11%, risk difference 8% (95% CI: 0.1%-16%); P = 0.020]. The percentage of trials not published as full journal article was similar in surgical and medical trials (44% vs 40%, risk difference 4% (95% CI: -5% to 14%); P = 0.373). Discontinuation of surgical trials was a strong risk factor for nonpublication (odds ratio = 4.18, 95% CI: 1.45-12.06; P = 0.008). CONCLUSIONS: Discontinuation and nonpublication rates were substantial in surgical RCTs and trial discontinuation was strongly associated with nonpublication. These findings need to be taken into account when interpreting surgical literature. Surgical trialists should consider feasibility studies before embarking on full-scale trials.

Labour Market Prospects of Swiss Career Entrants after Completion of Vocational Education and Training

This study seeks to find the reasons for the rising risk of unemployment for people who have completed basic vocational education and training (VET) in Switzerland. We focus on the long-term structural shift on the demand side of the labour market and its consequences for new entrants? chances of employment in the labour force. A detailed analysis of the development of vacancies for such ?career entrants? in the time period 2001 to 2011 suggests that neither a growing occupational mismatch nor a general shift in the level of education to the disadvantage of workers with vocational education can be made responsible for the rising unemployment of labour market entrants. Instead, the available evidence indicates that a diminishing part of the vacancies suited for VET graduates remains open to entrants because of the increasing job requirements with regard to work experience and further education. Basic vocational education and training alone is increasingly less a guarantee for a smooth entry into the working world.