Optimal Lower Bounds for Projective List Update Algorithms

The list update problem is a classical online problem, with an optimal competitive ratio that is still open, known to be somewhere between 1.5 and 1.6. An algorithm with competitive ratio 1.6, the smallest known to date, is COMB, a randomized combination of BIT and the TIMESTAMP algorithm TS. This and almost all other list update algorithms, like MTF, are projective in the sense that they can be defined by looking only at any pair of list items at a time. Projectivity (also known as "list factoring") simplifies both the description of the algorithm and its analysis, and so far seems to be the only way to define a good online algorithm for lists of arbitrary length. In this paper we characterize all projective list update algorithms and show that their competitive ratio is never smaller than 1.6 in the partial cost model. Therefore, COMB is a best possible projective algorithm in this model.Comment: Version 3 same as version 2, but date in LaTeX \today macro replaced by March 8, 201

Imaging of nanoparticle-labeled stem cells using magnetomotive optical coherence tomography, laser speckle reflectometry, and light microscopy

Cell transplantation and stem cell therapy are promising approaches for regenerative medicine and are of interest to researchers and clinicians worldwide. However, currently, no imaging technique that allows three-dimensional in vivo inspection of therapeutically administered cells in host tissues is available. Therefore, we investigate magnetomotive optical coherence tomography (MM-OCT) of cells labeled with magnetic particles as a potential noninvasive cell tracking method. We develop magnetomotive imaging of mesenchymal stem cells for future cell therapy monitoring. Cells were labeled with fluorescent iron oxide nanoparticles, embedded in tissue-mimicking agar scaffolds, and imaged using a microscope setup with an integrated MM-OCT probe. Magnetic particle-induced motion in response to a pulsed magnetic field of 0.2 T was successfully detected by OCT speckle variance analysis, and cross-sectional and volumetric OCT scans with highlighted labeled cells were obtained. In parallel, fluorescence microscopy and laser speckle reflectometry were applied as two-dimensional reference modalities to image particle distribution and magnetically induced motion inside the sample, respectively. All three optical imaging modalities were in good agreement with each other. Thus, magnetomotive imaging using iron oxide nanoparticles as cellular contrast agents is a potential technique for enhanced visualization of selected cells in OCT

FDG-PET underscores the key role of the thalamus in frontotemporal lobar degeneration caused by C9ORF72 mutations

C9ORF72 mutations are the most common cause of familial frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). MRI studies have investigated structural changes in C9ORF72-associated FTLD (C9FTLD) and provided first insights about a prominent involvement of the thalamus and the cerebellum. Our multicenter, F-18-fluorodeoxyglucose positron-emission tomography study of 22 mutation carriers with FTLD, 22 matched non-carriers with FTLD, and 23 cognitively healthy controls provided valuable insights into functional changes in C9FTLD: compared to non-carriers, mutation carriers showed a significant reduction of glucose metabolism in both thalami, underscoring the key role of the thalamus in C9FTLD. Thalamic metabolism did not correlate with disease severity, duration of disease, or the presence of psychotic symptoms. Against our expectations we could not demonstrate a cerebellar hypometabolism in carriers or non-carriers. Future imaging and neuropathological studies in large patient cohorts are required to further elucidate the central role of the thalamus in C9FTLD

Optimal projective algorithms for the list update problem

The list update problem is a classical online problem, with an optimal competitive ratio that is still open, known to be somewhere between 1.5 and 1.6. An algorithm with competitive ratio 1.6, the smallest known to date, is COMB, a randomized combination of BIT and TIMESTAMP(0). This and many other known algorithms, like MTF, are projective in the sense that they can be defined by looking only at any pair of list items at a time. Projectivity simplifies both the description of the algorithm and its analysis, and so far seems to be the only way to define a good online algorithm for lists of arbitrary length. In this paper we characterize all projective list update algorithms and show that their competitive ratio is never smaller than 1.6 in the partial cost model. Therefore, COMB is a best possible projective algorithm in this model

Non-cancer patients in specialized palliative care in Germany: What are the problems?

To determine the role of non-cancer palliative care in inpatient services in Germany, data from the Hospice and Palliative Care Evaluation (HOPE) were analysed. Since 1999, a three-month census has been conducted annually in German palliative care units. Pooled data from 2002–2005 were tested for differences between non-cancer patients (NCs) and cancer patients (Cs). A total of 4182 patients (NC: 3.5%; C: 96.5%) were documented; functional status (using Eastern Cooperative Oncology Group (ECOG) measures) in NCs was lower compared to Cs (p = 0.009). NCs suffered more often from dyspnoea (40%; C: 29%; p = 0.004), weakness (92,3%; C: 84,5%; p = 0.011) and tiredness (75.4%; C: 66.7%; p = 0.03) and less from nausea (17.1%; C: 28.9%; p = 0.002), vomiting (8.2%; C: 19.4%; p = 0.001) or loss of appetite (55.5%; C: 67.9%; p = 0.002). There were no differences in pain and constipation. Other problems (nursing, psychological) were more frequent for NCs, in particular the need for support in the activities of daily life (90.3%; C: 72.8%; p < 0.001) and disorientation/confusion (32.1%; C: 17.2%; p < 0.001). There were no differences in social problems. NCs are still rare in specialized inpatient palliative care institutions in Germany. The palliative care needs in patients with non-malignant disease will challenge the health care system as the workload for these services will grow over proportionally

EffenDys-Fentanyl Buccal Tablet for the Relief of Episodic Breathlessness in Patients With Advanced Cancer: A Multicenter, Open-Label, Randomized, Morphine-Controlled, Crossover, Phase II Trial

Context. Episodic breathlessness is a frequent and burdensome symptom in cancer patients but pharmacological treatment is limited. Objectives. To determine time to onset, efficacy, feasibility, and safety of transmucosal fentanyl in comparison to immediate-release morphine for the relief of episodic breathlessness. Methods. Phase II, investigator-initiated, multicenter, open-label, randomized, morphine-controlled, crossover trial with openlabel titration of fentanyl buccal tablet (FBT) in inpatients with incurable cancer. The primary outcome was time to onset of meaningful breathlessness relief. Secondary outcomes were efficacy (breathlessness intensity difference at 10 and 30 minutes; sum of breathlessness intensity difference at 15 and 60 minutes), feasibility, and safety. Study was approved by local ethics committees. Results. Twenty-five of 1341 patients were eligible, 10 patients agreed to participate (four female, mean age 58 +/- 11, mean Karnofsky score 67 +/- 11). Two patients died before final visits and two patients dropped-out because of disease progression leaving six patients for analysis with 61 episodes of breathlessness. Mean time to onset was for FBT 12.7 +/- 10.0 and for immediate-release morphine 23.6 +/- 15.1 minutes with a mean difference of -10.9 minutes (95% CI - -24.5 to 2.7, P = 0.094). Efficacy measures were predominately in favor for FBT. Both interventions were safe. Feasibility failed because of too much study demands for a very ill patient group. Conclusion. The description of a faster and greater relief of episodic breathlessness by transmucosal fentanyl versus morphine justifies further evaluation by a full-powered trial. (C) 2016 Published by Elsevier Inc. on behalf of American Academy of Hospice and Palliative Medicine

Pre-surgery optimization of patients' expectations to improve outcome in heart surgery: Study protocol of the randomized controlled multi-center PSY-HEART-II trial

The PSY-HEART-I trial indicated that a brief expectation-focused intervention prior to heart surgery improves disability and quality of life 6 months after coronary artery bypass graft surgery (CABG). However, to investigate the clinical utility of such an intervention, a large multi-center trial is needed to generalize the results and their implications for the health care system. The PSY-HEART-II study aims to examine whether a preoperative psychological intervention targeting patients' expectations (EXPECT) can improve outcomes 6 months after CABG (with or without heart valve replacement). EXPECT will be compared to Standard of Care (SOC) and an intervention providing emotional support without targeting expectations (SUPPORT). In a 3-arm multi-center randomized, controlled, prospective trial (RCT), N = 567 patients scheduled for CABG surgery will be randomized to either SOC alone or SOC and EXPECT or SOC and SUPPORT. Patients will be randomized with a fixed unbalanced ratio of 3:3:1 (EXPECT: SUPPORT: SOC) to compare EXPECT to SOC and EXPECT to SUPPORT. Both psychological interventions consist of 2 in-person sessions (a 50 minute), 2 phone consultations (a 20 minute) during the week prior to surgery, and 1 booster phone consultation post-surgery 6 weeks later. Assessment will occur at baseline approx. 3-10 days before surgery, preoperatively the day before surgery, 4-6 days later, and 6 months after surgery. The study's primary end point will be patients' illness-related disability 6 months after surger y. Secondar y outcomes will be patients' expectations, subjective illness beliefs, quality of life, length of hospital stay and blood sample parameters (eg, inflammatory parameters such as IL-6, IL-8, CRP). This large multi-center trial has the potential to corroborate and generalize the promising results of the PSY-HEART-I trial for routine care of cardiac surgery patients, and to stimulate revisions of treatment guidelines in heart surgery. (Am Heart J 2022;254:1-11.

Cortical Amyloid Burden Relates to Basal Forebrain Volume in Subjective Cognitive Decline.

BACKGROUND Atrophy of cholinergic basal forebrain (BF) nuclei is a frequent finding in magnetic resonance imaging (MRI) volumetry studies that examined patients with prodromal or clinical Alzheimer's disease (AD), but less clear for individuals in earlier stages of the clinical AD continuum. OBJECTIVE To examine BF volume reductions in subjective cognitive decline (SCD) participants with AD pathologic changes. METHODS The present study compared MRI-based BF volume measurements in age- and sex-matched samples of N = 24 amyloid-positive and N = 24 amyloid-negative SCD individuals, based on binary visual ratings of Florbetaben positron emission tomography (PET) measurements. Additionally, we assessed associations of BF volume with cortical amyloid burden, based on semiquantitative Centiloid (CL) analyses. RESULTS Group differences approached significance for BF total volume (p = 0.061) and the Ch4 subregion (p = 0.059) only, showing the expected relative volume reductions for the amyloid-positive subgroup. There were also significant inverse correlations between BF volumes and CL values, which again were most robust for BF total volume and the Ch4 subregion. CONCLUSIONS The results are consistent with the hypothesis that amyloid-positive SCD individuals, which are considered to represent a transitional stage on the clinical AD continuum, already show incipient alterations of BF integrity. The negative association with a continuous measure of cortical amyloid burden also suggests that this may reflect an incremental process. Yet, further research is needed to evaluate whether BF changes already emerge at "grey zone" levels of amyloid accumulation, before amyloidosis is reliably detected by PET visual readings