3,119 research outputs found
High-fidelity transmission of entanglement over a high-loss freespace channel
Quantum entanglement enables tasks not possible in classical physics. Many
quantum communication protocols require the distribution of entangled states
between distant parties. Here we experimentally demonstrate the successful
transmission of an entangled photon pair over a 144 km free-space link. The
received entangled states have excellent, noise-limited fidelity, even though
they are exposed to extreme attenuation dominated by turbulent atmospheric
effects. The total channel loss of 64 dB corresponds to the estimated
attenuation regime for a two-photon satellite quantum communication scenario.
We confirm that the received two-photon states are still highly entangled by
violating the CHSH inequality by more than 5 standard deviations. From a
fundamental point of view, our results show that the photons are virtually not
subject to decoherence during their 0.5 ms long flight through air, which is
encouraging for future world-wide quantum communication scenarios.Comment: 5 pages, 3 figures, replaced paper with published version, added
journal referenc
Procollagen type 1 N-terminal propeptide is associated with adverse outcome in acute chest pain of suspected coronary origin
Background: Extracellular matrix (ECM) is an integral player in the pathophysiology
of a variety of cardiac diseases. Cardiac ECM is composed mainly of collagen, of
which type 1 is the most abundant with procollagen type 1 N-terminal
Propeptide (P1NP) as a formation marker. P1NP is associated with mortality in
the general population, however, its role in myocardial infarction (MI) is still
uncertain, and P1NP has not been investigated in acute chest pain. The
objective of the current study was to assess the role of P1NP in undifferentiated
acute chest pain of suspected coronary origin.
Methods and results: 813 patients from the Risk in Acute Coronary Syndromes
study were included. This was a single-center study investigating biomarkers in
consecutively enrolled patients with acute chest pain of suspected coronary
origin, with a follow-up for up to 7 years. Outcome measures were a composite
endpoint of all-cause death, new MI or stroke, as well as its individual
components at 1, 2, and 7 years, and cardiac death at 1 and 2 years. In
multivariable Cox regression analysis, quartiles of P1NP were significantly
associated with the composite endpoint at 1 year of follow-up with a hazard
ratio for Q4 of 1.82 (95% CI, 1.12β2.98). There was no other significant
association with outcomes at any time points.
Conclusion: P1NP was found to be an independent biomarker significantly
associated with adverse clinical outcome at one year in patients admitted to
hospital for acute chest pain of suspected coronary origin. This is the first report
in the literature on the prognostic value of P1NP in this clinical setting
Antifungal prophylaxis in chemotherapy-associated neutropenia: a retrospective, observational study
<p>Abstract</p> <p>Background</p> <p>In August 2002, the antifungal prophylaxis algorithm for neutropenic hematology/oncology (NHO) patients at the Medical Center was changed from conventional amphotericin (AMB) to an azole (AZ) based regimen (fluconazole [FLU] in low-risk and voriconazole [VOR] in high-risk patients). The aim of our study was to compare outcomes associated with the two regimens, including breakthrough fungal infection, adverse drug events, and costs.</p> <p>Methods</p> <p>Adult, non-febrile, NHO patients who received prophylactic AMB from 8/01/01-7/30/02 or AZ from 8/01/02-7/30/03 were retrospectively evaluated.</p> <p>Results</p> <p>A total of 370 patients (AMB: n = 181; AZ: n = 216) associated with 580 hospitalizations (AMB: n = 259; AZ: n = 321) were included. The incidence of probable/definite breakthrough Aspergillus infections was similar among regimens (AMB: 1.9% vs AZ: 0.6%; p=0.19). A greater incidence of mild/moderate (24.7% vs. 5.3%; p < 0.0001) and severe renal dysfunction (13.5% vs. 4.4%; p < 0.0012) was observed with AMB. In contrast, patients treated with VOR were found to have an increased rate of severe hepatic toxicity (32.5%) compared with patients treated with either AMB (22.6%) or FLU (21.4%) (p = 0.05). While the AZ period was associated with a >947/hospitalization more than AMB.</p> <p>Conclusion</p> <p>While an AZ-based regimen is associated with increased cost, the reduced rate of nephrotoxicity and availability of oral dosage forms, suggests that azoles be used preferentially over AMB. However, an increased rate of severe hepatic toxicity may be associated with VOR.</p
Effect of preoperative thoracic duct drainage on canine kidney transplantation
Chronic drainage of the thoracic duct to the esophagus was developed in dogs, and its efficacy in immunomodulation was tested using kidney transplantation. Compared to 9.7 days in the control, the mean animal survival was prolonged to 9.9 days, 17.8 days, and 18.5 days when TDD was applied preoperatively for 3 weeks, 6 weeks, and 9 weeks, respectively. Prolongation was significant after 6 weeks. Patency of the fistula was 93.5, 80.4, and 76.1% at respective weeks. Number of peripheral T-lymphocytes determined by a new monoclonal antibody diminished after 3 weeks. All animals were in normal health, requiring no special care for fluid, electrolyte, or protein replacement
Abnormalities in autonomic function in obese boys at-risk for insulin resistance and obstructive sleep apnea.
Study objectivesCurrent evidence in adults suggests that, independent of obesity, obstructive sleep apnea (OSA) can lead to autonomic dysfunction and impaired glucose metabolism, but these relationships are less clear in children. The purpose of this study was to investigate the associations among OSA, glucose metabolism, and daytime autonomic function in obese pediatric subjects.MethodsTwenty-three obese boys participated in: overnight polysomnography; a frequently sampled intravenous glucose tolerance test; and recordings of spontaneous cardiorespiratory data in both the supine (baseline) and standing (sympathetic stimulus) postures.ResultsBaseline systolic blood pressure and reactivity of low-frequency heart rate variability to postural stress correlated with insulin resistance, increased fasting glucose, and reduced beta-cell function, but not OSA severity. Baroreflex sensitivity reactivity was reduced with sleep fragmentation, but only for subjects with low insulin sensitivity and/or low first-phase insulin response to glucose.ConclusionsThese findings suggest that vascular sympathetic activity impairment is more strongly affected by metabolic dysfunction than by OSA severity, while blunted vagal autonomic function associated with sleep fragmentation in OSA is enhanced when metabolic dysfunction is also present
Misconceptions about Aerobic and Anaerobic Energy Expenditure
The measurement of gas exchange has played an invaluable role in metabolic interpretation. The uptake of 1 liter of oxygen is often converted into an energy expenditure estimate of 21.1 kilojoules (e.g., 1 L O2 = 21.1 kJ or ~5 kcal). This article demonstrates both the importance of such a conversion and the potential for misinterpretation. Oxygen uptake during heavy and severe exercise will also be discussed
Towards W b bbar + j at NLO with an automatized approach to one-loop computations
We present results for the O(alpha_s) virtual corrections to q g -> W b bbar
q' obtained with a new automatized approach to the evaluation of one-loop
amplitudes in terms of Feynman diagrams. Together with the O(alpha_s)
corrections to q q' -> W b bbar g, which can be obtained from our results by
crossing symmetry, this represents the bulk of the next-to-leading order
virtual QCD corrections to W b bbar + j and W b + j hadronic production,
calculated in a fixed-flavor scheme with four light flavors. Furthermore, these
corrections represent a well defined and independent subset of the 1-loop
amplitudes needed for the NNLO calculation of W b bbar. Our approach was tested
against several existing results for NLO amplitudes including selected
O(alpha_s) one-loop corrections to W + 3 j hadronic production. We discuss the
efficiency of our method both with respect to evaluation time and numerical
stability.Comment: 14 pages, 3 figure
Is lymphadenectomy a prognostic marker in endometrioid adenocarcinoma of the human endometrium?
<p>Abstract</p> <p>Background</p> <p>During surgery for endometrial cancer, a pelvic lymphadenectomy with or without para-aortic lymphadenectomy is performed at least in patients with risk factors (stage I, grading 2 and/or histological subtypes with higher risk of lymphatic spread), and is hence recommended by the International Federation of Obstetrics and Gynecology (FIGO). Although lymph node metastases are important prognostic parameters, it has been contentious whether a pelvic lymph node dissection itself has a prognostic impact in the treatment of endometrial cancer, especially in endometrioid adenocarcinoma. Therefore, this study evaluated whether lymphadenectomy has a prognostic impact in patients with endometrioid adenocarcinoma.</p> <p>Methods</p> <p>The benefits of lymphadenectomy were examined in 214 patients with a histological diagnosis of endometrial adenocarcinoma. Tumour characteristics were analysed with respect to the surgical and pathological stage.</p> <p>Results</p> <p>Of the 214 patients with endometrial adenocarcinoma, 171 (79.9%) were classified as FIGO stage I, 15 (7.0%) FIGO stage II, 21 (9.8%) FIGO stage III and 7 (3.3%) FIGO stage IV. One hundred and thirty four (62.6%) of the patients had a histological grade 1 tumour, while 56 (26.2%) and 24 (11.2%) had a histological grade 2 or grade 3 tumour, respectively. Lymphadenectomy was performed in 151 (70.6%) patients. Only 11 (5.1%) patients showed metastatic disease in the lymph nodes. The performance of a lymphadenectomy resulted in significantly increased cause-specific and overall survival, while progression-free survival was not affected by this operative procedure.</p> <p>Conclusions</p> <p>The performance of an operative lymphadenectomy resulted in better survival of patients with endometrioid adenocarcinoma. This increase was significant for cause-specific and overall survival, while there was a tendency only towards increased progression-free survival. Therefore, even in endometrioid adenocarcinoma, a pelvic and/or para-aortic lymphadenectomy should be performed.</p
The Role of Innate APOBEC3G and Adaptive AID Immune Responses in HLA-HIV/SIV Immunized SHIV Infected Macaques
This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Serotonin and corticosterone rhythms in mice exposed to cigarette smoke and in patients with COPD:implication for COPD-associated neuropathogenesis
The circadian timing system controls daily rhythms of physiology and behavior, and disruption of clock function can trigger stressful life events. Daily exposure to cigarette smoke (CS) can lead to alteration in diverse biological and physiological processes. Smoking is associated with mood disorders, including depression and anxiety. Patients with chronic obstructive pulmonary disease (COPD) have abnormal circadian rhythms, reflected by daily changes in respiratory symptoms and lung function. Corticosterone (CORT) is an adrenal steroid that plays a considerable role in stress and anti-inflammatory responses. Serotonin (5-hydroxytryptamine; 5HT) is a neurohormone, which plays a role in sleep/wake regulation and affective disorders. Secretion of stress hormones (CORT and 5HT) is under the control of the circadian clock in the suprachiasmatic nucleus. Since smoking is a contributing factor in the development of COPD, we hypothesize that CS can affect circadian rhythms of CORT and 5HT secretion leading to sleep and mood disorders in smokers and patients with COPD. We measured the daily rhythms of plasma CORT and 5HT in mice following acute (3 d), sub-chronic (10 d) or chronic (6 mo) CS exposure and in plasma from non-smokers, smokers and patients with COPD. Acute and chronic CS exposure affected both the timing (peak phase) and amplitude of the daily rhythm of plasma CORT and 5HT in mice. Acute CS appeared to have subtle time-dependent effects on CORT levels but more pronounced effects on 5HT. As compared with CORT, plasma 5HT was slightly elevated in smokers but was reduced in patients with COPD. Thus, the effects of CS on plasma 5HT were consistent between mice and patients with COPD. Together, these data reveal a significant impact of CS exposure on rhythms of stress hormone secretion and subsequent detrimental effects on cognitive function, depression-like behavior, mood/anxiety and sleep quality in smokers and patients with COPD
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