964 research outputs found
Time spent in hospital after liver transplantation: Effects of primary liver disease and comorbidity.
AIM: To explore the effect of primary liver disease and comorbidities on transplant length of stay (TLOS) and LOS in later admissions in the first two years after liver transplantation (LLOS). METHODS: A linked United Kingdom Liver Transplant Audit - Hospital Episode Statistics database of patients who received a first adult liver transplant between 1997 and 2010 in England was analysed. Patients who died within the first two years were excluded from the primary analysis, but a sensitivity analysis was also performed including all patients. Multivariable linear regression was used to evaluate the impact of primary liver disease and comorbidities on TLOS and LLOS. RESULTS: In 3772 patients, the mean (95%CI) TLOS was 24.8 (24.2 to 25.5) d, and the mean LLOS was 24.2 (22.9 to 25.5) d. Compared to patients with cancer, we found that the largest difference in TLOS was seen for acute hepatic failure group (6.1 d; 2.8 to 9.4) and the largest increase in LLOS was seen for other liver disease group (14.8 d; 8.1 to 21.5). Patients with cardiovascular disease had 8.5 d (5.7 to 11.3) longer TLOS and 6.0 d (0.2 to 11.9) longer LLOS, compare to those without. Patients with congestive cardiac failure had 7.6 d longer TLOS than those without. Other comorbidities did not significantly increase TLOS nor LLOS. CONCLUSION: The time patients spent in hospital varied according to their primary liver disease and some comorbidities. Time spent in hospital of patients with cancer was relatively short compared to most other indications. Cardiovascular disease and congestive cardiac failure were the comorbidities with a strong impact on increased LOS
Bichromatic dressing of a quantum dot detected by a remote second quantum dot
We demonstrate an information transfer mechanism between two dissimilar remote InAs/GaAs quantum dots weakly coupled to a common photonic crystal microcavity. Bichromatic excitation in the s state of one of the dots leads to the formation of dressed states due to the coherent coupling to the laser field, in resonance with the quantum dot. Information on the resulting dressed structure is read out through the photoluminescence spectrum of the other quantum dot, as well as the cavity mode. The effect is also observed upon exchange of the excitation and detection quantum dots. This quantum dot intertalk is interpreted in terms of a cavity-mediated coupling involving acoustic phonons. A master equation for a three-level system coherently pumped by the two lasers quantitatively describes the behavior of our system. Our result presents an important step towards scalable solid-state quantum networking based on coupled multi-quantum-dot-cavity systems, without the need to use identical quantum emittersThis work was supported by the Spanish MINECO under Contract No. MAT2011-22997, by CAM under Contract No. S2009/ESP-1503, and by the FP7 ITN Spin-optronics (237252). C.S-M. and E.C. acknowledge FPI gran
Primary therapy and survival in patients over 70 years old with primary central nervous system lymphoma:a contemporary, nationwide, population-based study in the Netherlands
A guide to evaluating linkage quality for the analysis of linked data.
Linked datasets are an important resource for epidemiological and clinical studies, but linkage error can lead to biased results. For data security reasons, linkage of personal identifiers is often performed by a third party, making it difficult for researchers to assess the quality of the linked dataset in the context of specific research questions. This is compounded by a lack of guidance on how to determine the potential impact of linkage error. We describe how linkage quality can be evaluated and provide widely applicable guidance for both data providers and researchers. Using an illustrative example of a linked dataset of maternal and baby hospital records, we demonstrate three approaches for evaluating linkage quality: applying the linkage algorithm to a subset of gold standard data to quantify linkage error; comparing characteristics of linked and unlinked data to identify potential sources of bias; and evaluating the sensitivity of results to changes in the linkage procedure. These approaches can inform our understanding of the potential impact of linkage error and provide an opportunity to select the most appropriate linkage procedure for a specific analysis. Evaluating linkage quality in this way will improve the quality and transparency of epidemiological and clinical research using linked data
Gamma-Ray Spectra & Variability of the Crab Nebula Emission Observed by BATSE
We report ~ 600 days of BATSE earth-occultation observations of the total
gamma-ray (30 keV to 1.7 MeV) emission from the Crab nebula, between 1991 May
24 (TJD 8400) and 1994 October 2 (TJD 9627). Lightcurves from 35-100, 100-200,
200-300, 300-400, 400-700, and 700-1000 keV, show that positive fluxes were
detected by BATSE in each of these six energy bands at significances of
approximately 31, 20, 9.2, 4.5, 2.6, and 1.3 sigma respectively per day. We
also observed significant flux and spectral variations in the 35-300 keV energy
region, with time scales of days to weeks. The spectra below 300 keV, averaged
over typical CGRO viewing periods of 6-13 days, can be well described by a
broken power law with average indices of ~ 2.1 and ~ 2.4 varying around a
spectral break at ~ 100 keV. Above 300 keV, the long-term averaged spectra,
averaged over three 400 d periods (TJD 8400-8800, 8800-9200, and 9200-9628,
respectively) are well represented by the same power law with index of ~ 2.34
up to ~ 670 keV, plus a hard spectral component extending from ~ 670 keV to ~
1.7 MeV, with a spectral index of ~ 1.75. The latter component could be related
to a complex structure observed by COMPTEL in the 0.7-3 MeV range. Above 3 MeV,
the extrapolation of the power-law continuum determined by the low-energy BATSE
spectrum is consistent with fluxes measured by COMPTEL in the 3-25 MeV range,
and by EGRET from 30-50 MeV. We interpret these results as synchrotron emission
produced by the interaction of particles ejected from the pulsar with the field
in different dynamical regions of the nebula system, as observed recently by
HST, XMM-Newton, and Chandra.Comment: To be published in the November 20, 2003, Vol 598 issue of the
Astrophysical Journa
Insight into the neurophysiological processes of melodically intoned language with functional MRI
Background: Melodic Intonation Therapy (MIT) uses the melodic elements of speech to improve language production in severe nonfluent aphasia. A crucial element of MIT is the melodically intoned auditory input: the patient listens to the therapist singing a target utterance. Such input of melodically intoned language facilitates production, whereas auditory input of spoken language does not. Methods: Using a sparse sampling fMRI sequence, we examined the differential auditory processing of spoken and melodically intoned language. Nineteen right-handed healthy volunteers performed an auditory lexical decision task in an event related design consisting of spoken and melodically intoned meaningful and meaningless items. The control conditions consisted of neutral utterances, either melodically intoned or spoken. Results: Irrespective of whether the items were normally spoken or melodically intoned, meaningful items showed greater activation in the supramarginal gyrus and inferior parietal lobule, predominantly in the left hemisphere. Melodically intoned language activated both temporal lobes rather symmetrically, as well as the right frontal lobe cortices, indicating that these regions are engaged in the acoustic complexity of melodically intoned stimuli. Compared to spoken language, melodically intoned language activated sensory motor regions and articulatory language networks in the left hemisphere, but only when meaningful language was used. Discussion: Our results suggest that the facilitatory effect of MIT may - in part - depend on an auditory input which combines melody and meaning. Conclusion: Combined melody and meaning provide a sound basis for the further investigation of melodic language processing in aphasic patients, and eventually the neurophysiological processes underlying MIT. Compared to spoken language, melodically intoned language activated sensory motor regions and articulatory language networks in the left hemisphere, but only when meaningful language was used. Our results suggest that the facilitatory effect of MIT may - in part - depend on an auditory input which combines melody and meaning. As such, they provide a sound basis for further investigation of melodic language processing in aphasic patients, and eventually the neurophysiological processes underlying MIT
The effect of induction therapy with infliximab or vedolizumab on hepcidin and iron status in patients with Inflammatory Bowel Disease
Background Differentiating absolute iron deficiency from functional iron restriction is challenging in active Inflammatory Bowel Disease (IBD). Hepcidin, the systemic iron regulator, could be the key in the diagnosis and management of absolute iron deficiency. In this study, we assessed hepcidin as a diagnostic iron deficiency marker and we explored the relationship between hepcidin, inflammation, hypoxia, and iron deficiency in patients receiving induction therapy with infliximab (IFX) or vedolizumab (VEDO). Methods 130 patients with IBD, who received induction therapy with IFX or VEDO for active disease, were included in this study. Clinical and biochemical data were extracted from medical records. Serum samples at baseline and week 6 of induction therapy were retrieved from the University Medical Center Groningen (UMCG) biobank and analysed for: hepcidin, inflammation (e.g., interleukins [IL] 6, 10, and Tumour Necrosis Factor-α [TNFα]), oxidative stress (free thiols), and hypoxia (e.g., erythropoietin [EPO], Macrophage Inflammatory Protein-3α [MIP3α]). For comparison, serum samples from 50 age- and gender-matched healthy controls were obtained from pre-donation biobank at the UMCG. Response to therapy was defined by either General Physicianâs Assessment at week 14 of induction therapy, normalisation or at least a three-point decrease in clinical scores: Harvey-Bradshaw Index (HBI) for Crohnâs Disease, Simple Clinical Colitis Activity Index (SCCAI) for ulcerative colitis. Results Hepcidin correlated with ferritin and sTfR/log ferritin index [Ï = 0.74 and Ï = -0.79, respectively; P<0.001 for both markers], while inflammation- and hypoxia-associated markers showed only marginal correlations. Hepcidin accurately identified absolute iron deficiency: AUC(hepcidin) = 0.89 [95% CI: 0.82â0.95; P<0.001]. Induction with either IFX or VEDO decreased hepcidin [13.5 ng/mL vs. 9.5 ng/mL; P<0.001], ferritin [45.5 ug/L vs. 37.0 ug/L, P<0.05], and inflammatory markers at week 6, while transferrin increased [2.4 g/L vs. 2.5 g/L, P<0.001]. In total, 75.4% of patients responded to the induction therapy. Hepcidin and ferritin decreased, while transferrin increased (P<0.001 for all changes) in patients who responded to the therapy. In addition, hypoxia (EPO and MIP3α) and inflammatory markers such as faecal calprotectin, IL-6, IL-22, and TNFα improved significantly. In contrast, none of these improvements were observed in patients who did not respond to the therapy. Conclusion Hepcidin reflects iron deficiency in active IBD, but inflammation masks the severity of the deficiency. Induction therapy with either IFX or VEDO modulates hepcidin and iron indices, especially in patients who respond to the therapy
Photodissociation of the OD radical at 226 and 243 nm
The photodissociation dynamics of state selected OD radicals has been examined at 243 and 226 nm using velocity map imaging to probe the angleâspeed distributions of theD(2S) and O(3P2) products. Both experiment and complementary first principle calculations demonstrate that photodissociation occurs by promotion of OD from high vibrational levels of the ground Xâ2Î state to the repulsive 1â2ÎŁâ state
Scaling in a continuous time model for biological aging
In this paper we consider a generalization to the asexual version of the
Penna model for biological aging, where we take a continuous time limit. The
genotype associated to each individual is an interval of real numbers over
which Dirac --functions are defined, representing genetically
programmed diseases to be switched on at defined ages of the individual life.
We discuss two different continuous limits for the evolution equation and two
different mutation protocols, to be implemented during reproduction. Exact
stationary solutions are obtained and scaling properties are discussed.Comment: 10 pages, 6 figure
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