540 research outputs found

    Two-particle interference of electron pairs on a molecular level

    Full text link
    We investigate the photo-doubleionization of H2H_2 molecules with 400 eV photons. We find that the emitted electrons do not show any sign of two-center interference fringes in their angular emission distributions if considered separately. In contrast, the quasi-particle consisting of both electrons (i.e. the "dielectron") does. The work highlights the fact that non-local effects are embedded everywhere in nature where many-particle processes are involved

    Searching for Lee-Wick Gauge Bosons at the LHC

    Get PDF
    In an extension of the Standard Model(SM) based on the ideas of Lee and Wick, Grinstein, O'Connell and Wise have found an interesting way to remove the usual quadratically divergent contributions to the Higgs mass induced by radiative corrections. Phenomenologically, the model predicts the existence of Terascale, negative-norm copies of the usual SM fields with rather unique properties: ghost-like propagators and negative decay widths, but with otherwise SM-like couplings. The model is both unitary and causal on macroscopic scales. In this paper we examine whether or not such states with these unusual properties can be uniquely identified as such at the LHC. We find that in the extended strong and electroweak gauge boson sector of the model, which is the simplest one to analyze, such an identification can be rather difficult. Observation of heavy gluon-like resonances in the dijet channel offers the best hope for this identification.Comment: 17 pages, 4 figs; discussion adde

    Developing core sets for persons following amputation based on the International Classification of Functioning, Disability and Health as a way to specify functioning

    Get PDF
    Amputation is a common late stage sequel of peripheral vascular disease and diabetes or a sequel of accidental trauma, civil unrest and landmines. The functional impairments affect many facets of life including but not limited to: Mobility; activities of daily living; body image and sexuality. Classification, measurement and comparison of the consequences of amputations has been impeded by the limited availability of internationally, multiculturally standardized instruments in the amputee setting. The introduction of the International Classification of Functioning, Disability and Health (ICF) by the World Health Assembly in May 2001 provides a globally accepted framework and classification system to describe, assess and compare function and disability. In order to facilitate the use of the ICF in everyday clinical practice and research, ICF core sets have been developed that focus on specific aspects of function typically associated with a particular disability. The objective of this paper is to outline the development process for the ICF core sets for persons following amputation. The ICF core sets are designed to translate the benefits of the ICF into clinical routine. The ICF core sets will be defined at a Consensus conference which will integrate evidence from preparatory studies, namely: (a) a systematic literature review regarding the outcome measures of clinical trails and observational studies, (b) semi-structured patient interviews, (c) international experts participating in an internet-based survey, and (d) cross-sectional, multi-center studies for clinical applicability. To validate the ICF core sets field-testing will follow. Invitation for participation: The development of ICF Core Sets is an inclusive and open process. Anyone who wishes to actively participate in this process is invited to do so

    Identification of the Rem-responsive element of mouse mammary tumor virus

    Get PDF
    Mouse mammary tumor virus (MMTV) has previously been shown to encode a functional homolog of the human immunodeficiency virus-1 (HIV-1) nuclear export protein Rev, termed Rem. Here, we show that deletion of the rem gene from a MMTV molecular clone interfered with the nucleo-cytoplasmic transport of genomic length viral mRNA and resulted in a loss of viral capsid (Gag) protein production. Interestingly, nuclear export of single-spliced env mRNA was only moderately affected, suggesting that this transcript is, at least to some extent, transported via a distinct, Rem-independent export mechanism. To identify and characterize a cis-acting RNA element required for Rem responsiveness (RmRE), extensive computational and functional analyses were performed. By these means a region of 490 nt corresponding to positions nt 8517–nt 9006 in the MMTV reference strain was identified as RmRE. Deletion of this fragment, which spans the env-U3 junction region, abolished Gag expression. Furthermore, insertion of this sequence into a heterologous HIV-1-based reporter construct restored, in the presence of Rem, HIV-1 Gag expression to levels determined for the Rev/RRE export system. These results clearly demonstrate that the identified region, whose geometry resembles that of other retroviral-responsive elements, is capable to functionally substitute, in the presence of Rem, for Rev/RRE and thus provide unequivocal evidence that MMTV is a complex retrovirus

    The inpatient burden of abdominal and gynecological adhesiolysis in the US

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Adhesions are fibrous bands of scar tissue, often a result of surgery, that form between internal organs and tissues, joining them together abnormally. Postoperative adhesions frequently occur following abdominal surgery, and are associated with a large economic burden. This study examines the inpatient burden of adhesiolysis in the United States (i.e., number and rate of events, cost, length of stay [LOS]).</p> <p>Methods</p> <p>Hospital discharge data for patients with primary and secondary adhesiolysis were analyzed using the 2005 Healthcare Cost and Utilization Project's Nationwide Inpatient Sample. Procedures were aggregated by body system.</p> <p>Results</p> <p>We identified 351,777 adhesiolysis-related hospitalizations: 23.2% for primary and 76.8% for secondary adhesiolysis. The average LOS was 7.8 days for primary adhesiolysis. We found that 967,332 days of care were attributed to adhesiolysis-related procedures, with inpatient expenditures totaling 2.3billion(2.3 billion (1.4 billion for primary adhesiolysis; 926millionforsecondaryadhesiolysis).Hospitalizationsforadhesiolysisincreasedsteadilybyageandwerehigherforwomen.Ofsecondaryadhesiolysisprocedures,46.3926 million for secondary adhesiolysis). Hospitalizations for adhesiolysis increased steadily by age and were higher for women. Of secondary adhesiolysis procedures, 46.3% involved the female reproductive tract, resulting in 57,005 additional days of care and 220 million in attributable costs.</p> <p>Conclusions</p> <p>Adhesiolysis remain an important surgical problem in the United States. Hospitalization for this condition leads to high direct surgical costs, which should be of interest to providers and payers.</p

    Imaging the square of the correlated two-electron wave function of a hydrogen molecule

    Get PDF
    The toolbox for imaging molecules is well-equipped today. Some techniques visualize the geometrical structure, others the electron density or electron orbitals. Molecules are many-body systems for which the correlation between the constituents is decisive and the spatial and the momentum distribution of one electron depends on those of the other electrons and the nuclei. Such correlations have escaped direct observation by imaging techniques so far. Here, we implement an imaging scheme which visualizes correlations between electrons by coincident detection of the reaction fragments after high energy photofragmentation. With this technique, we examine the H2two-electron wave function in which electron-electron correlation beyond the mean-field level is prominent. We visualize the dependence of the wave function on the internuclear distance. High energy photoelectrons are shown to be a powerful tool for molecular imaging. Our study paves the way for future time resolved correlation imaging at FELs and laser based X-ray sourcesThis work was funded by the Deutsche Forschungsgemeinschaft, the BMBF, the European Research Council under the European Union Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement 290853 XCHEM, the MINECO projects FIS2013-42002-R and FIS2016-77889-R, and the European COST Action XLIC CM1204. All calculations were performed at the CCC-UAM and Mare Nostrum Supercomputer Centers. We are grateful to the staff of PETRA III for excellent support during the beam time. K.M. and M.M. would like to thank the DFG for support via SFB925/A3. A.K. and V.S. thank the Wilhelm und Else Heraeus-Foundation for support. J.L. would like to thank the DFG for support. S.K. acknowledges support from the European Cluster of Advanced Laser Light Sources (EUCALL) project which has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 654220. T.W. was supported by the U.S. Department of Energy Basic Energy Sciences under Contract No. DE-AC02-05CH11231. A.P. acknowledges a Ramón y Cajal contract from the Ministerio de Economa y Competitivida

    Adhesion Awareness: A National Survey of Surgeons

    Get PDF
    Contains fulltext : 87943.pdf (publisher's version ) (Closed access)BACKGROUND: Postoperative adhesions are the most frequent complication of abdominal surgery, leading to high morbidity, mortality, and costs. However, the problem seems to be neglected by surgeons for largely unknown reasons. METHODS: A survey assessing knowledge and personal opinion about the extent and impact of adhesions was sent to all Dutch surgeons and surgical trainees. The informed-consent process and application of antiadhesive agents were questioned in addition. RESULTS: The response rate was 34.4%. Two thirds of all respondents (67.7%) agreed that adhesions exert a clinically relevant, negative effect. A negative perception of adhesions correlated with a positive attitude regarding adhesion prevention (rho = 0.182, p < 0.001). However, underestimation of the extent and impact of adhesions resulted in low knowledge scores (mean test score 37.6%). Lower scores correlated with more uncertainty about indications for antiadhesive agents which, in turn, correlated with never having used any of these agents (rho = 0.140, p = 0.002; rho = 0.095, p = 0.035; respectively). Four in 10 respondents (40.9%) indicated that they never inform patients on adhesions and only 9.8% informed patients routinely. A majority of surgeons (55.9%) used antiadhesive agents in the past, but only a minority (13.4%) did in the previous year. Of trainees, 82.1% foresaw an increase in the use of antiadhesive agents compared to 64.5% of surgeons (p < 0.001). CONCLUSIONS: The magnitude of the problem of postoperative adhesions is underestimated and informed consent is provided inadequately by Dutch surgeons. Exerting adhesion prevention is related to the perception of and knowledge about adhesions.1 december 201

    Establishing the baseline level of repetitive element expression in the human cortex

    Get PDF
    Background: Although nearly half of the human genome is comprised of repetitive sequences, the expression profile of these elements remains largely uncharacterized. Recently developed high throughput sequencing technologies provide us with a powerful new set of tools to study repeat elements. Hence, we performed whole transcriptome sequencing to investigate the expression of repetitive elements in human frontal cortex using postmortem tissue obtained from the Stanley Medical Research Institute. Results: We found a significant amount of reads from the human frontal cortex originate from repeat elements. We also noticed that Alu elements were expressed at levels higher than expected by random or background transcription. In contrast, L1 elements were expressed at lower than expected amounts. Conclusions: Repetitive elements are expressed abundantly in the human brain. This expression pattern appears to be element specific and can not be explained by random or background transcription. These results demonstrate that our knowledge about repetitive elements is far from complete. Further characterization is required to determine the mechanism, the control, and the effects of repeat element expression

    Ser/Thr/Tyr Protein Phosphorylation in the Archaeon Halobacterium salinarum—A Representative of the Third Domain of Life

    Get PDF
    In the quest for the origin and evolution of protein phosphorylation, the major regulatory post-translational modification in eukaryotes, the members of archaea, the “third domain of life”, play a protagonistic role. A plethora of studies have demonstrated that archaeal proteins are subject to post-translational modification by covalent phosphorylation, but little is known concerning the identities of the proteins affected, the impact on their functionality, the physiological roles of archaeal protein phosphorylation/dephosphorylation, and the protein kinases/phosphatases involved. These limited studies led to the initial hypothesis that archaea, similarly to other prokaryotes, use mainly histidine/aspartate phosphorylation, in their two-component systems representing a paradigm of prokaryotic signal transduction, while eukaryotes mostly use Ser/Thr/Tyr phosphorylation for creating highly sophisticated regulatory networks. In antithesis to the above hypothesis, several studies showed that Ser/Thr/Tyr phosphorylation is also common in the bacterial cell, and here we present the first genome-wide phosphoproteomic analysis of the model organism of archaea, Halobacterium salinarum, proving the existence/conservation of Ser/Thr/Tyr phosphorylation in the “third domain” of life, allowing a better understanding of the origin and evolution of the so-called “Nature's premier” mechanism for regulating the functional properties of proteins
    corecore