Ion acoustic waves in a collisional plasma

Damping of ion-acoustic waves by Coulomb collisions of ion and electron combination

Soft Tissue Substitutes at Immediate Postextractive Implants to Reduce Tissue Shrinkage – 3-year Results From a Randomized Controlled Trial

PURPOSE. The aim of this parallel randomized controlled trial (RCT) was to evaluate whether placement of a soft tissue graft substitute (STGS) could decrease peri-implant tissue shrinkage at immediate post-extractive implants. MATERIALS AND METHODS. Twenty patients with one missing tooth between two adja-cent healthy teeth in aesthetic areas and at least 4 mm of bone apically to the tooth apex were randomly allocated after tooth extraction to receive or not a subepithelial buccal STGS. Implants were inserted with a torque of at least 30 Ncm and sites were grafted with a cancellous particulate allograft. Ten patients received a buccal STGS and 10 patients did not (control group). All patients were restored with non-occluding immediate provisional screw-retained crowns, replaced after 6 months by definitive metal-ceramic crowns, and were followed to 3-year after grafting/loading. RESULTS. Three-year after loading, no drop-out, crown or implant failure or complication occurred. No statistically significant difference or trends in aesthetics (difference = 0.2, 95% CI:-0.81 to 1.21; P = 0.97), peri-implant marginal bone loss (difference = 0.14 mm; 95% CI:-0.27 to 0.57; P = 0.58) and keratinized mucosa heights (difference = 0.8 mm; 95% CI:-1.79 to 3.39; P = 0.57) between the two groups were observed. CONCLUSIONS. Acknowledging that the sample size was small, no clinical benefits could be observed using a soft tissue graft substitute at immediate post-extractive implants up to 3-year after grafting. CONFLICT OF INTEREST STATEMENT. The manufacturer (BEGO Implant Systems, Bremen, Germany) of the implants used in this investigation, partially supported this trial, however data belonged to the authors and by no means the sponsor interfered with the conduct of the trial or the publication of its results

Return current instability and its effects on beam-plasma system

The return current induced in a plasma by a relativisitc electron beam generates a new electron-ion two-stream instability (return current instability). Although the effect of these currents on the beam-plasma e-e instability is negligible, there exists a range of wave numbers which is unstable only to return current (RC) instability and not to e-e instability. The electromagnetic waves propagating along the direction of the external magnetic field, in which the plasma is immersed, are stabilized by these currents but the e.m. waves with frequencies,ω2≪Ω e 2 ≪ω pe 2 (Ω e and ω pe being cyclotron and plasma frequency for the electrons of the plasma respectively) propagating transverse to the magnetic field get destabilized. Heuristic estimates of plasma heating, due to RC instability and due to decay of ion-acoustic turbulence generated by the return current, are made. The fastest time scale on which the return current delivers energy to the plasma due to the scattering of ion-sound waves by the electrons can be ∼ω pi -1 (ω pi being the plasma frequency for the ions)

Bernstein modes in a weakly relativistic electron-positron plasma

The kinetic theory of weakly relativistic electron-positron plasmas, producing dispersion relations for the electrostatic Bernstein modes was addressed. The treatment presented preserves the full momentum dependence of the cyclotron frequency, albeit with a relaxation on the true relativistic form of the distribution function. The implications of this new treatment were confined largely to astrophysical plasmas, where relativistic electronpositron plasmas occur naturally

Validation of a new prognostic model to easily predict outcome in renal cell carcinoma: The GRANT score applied to the ASSURE trial population

Background: Prognostic scores have been developed to estimate the risk of recurrence and the probability of survival after nephrectomy for renal cell carcinoma (RCC). The use of these tools, despite being helpful to plan a customized schedule of follow-up, to the patient's tailored counselling and to select individuals who could potentially benefit from adjuvant treatment, currently is not routine, due to their relative complexity and to the lack of histological data (i.e. necrosis).Patients and methods: We developed a simple score called GRade, Age, Nodes and Tumor (GRANT) based on four easily obtained parameters: Fuhrman grade, age, pathological nodal status and pathological tumor size. Patients with 0 or 1 factor are classified as favorable risk, whereas patients with two or more risk factors as unfavorable risk. The large population of RCC patients from the ASSURE adjuvant trial was used as independent dataset for this external validation, to investigate the prognostic value of the new score in terms of disease-free survival and overall survival and to evaluate its possible application as predictive tool. Statistical analyses were carried out by the Department of Biostatistics & Computational Biology, Dana-Farber Cancer Institute (Boston, USA) for the ASSURE trial patients' population.Results: The performance of the new model is similar to that of the already validated score systems, but its strength, compared with the others already available, is the ease and clarity of its calculation, with great speed of use during the clinical practice. Limitations are the use of the Fuhrman nuclear grade, not valid for rare histologies, and the TNM classification modifications over time.Conclusion: The GRANT score demonstrated its potential usefulness for clinical practice

Hepatitis B e antigen status and hepatitis B DNA levels in women of childbearing age with chronic hepatitis B infection screening for clinical trials

BACKGROUND: Perinatal or mother-to-child transmission of hepatitis B virus (HBV) results in a high frequency of chronic infection. Risk of mother-to-child transmission is associated with maternal viral factors including hepatitis B e antigen (HBeAg) positivity and viral load. AIM: To investigate associations between age, HBeAg status, HBV DNA levels and genotype in female patients screened for inclusion into two contemporary, randomized HBV trials. METHODS: Retrospective analyses focused on differences between women of childbearing age (≤44 years) and older women. Female patients (N = 355; 18-69 years) were included in the analysis: 41.7% of patients were Asian. In total, 44.4% were HBeAg-positive. RESULTS: Significantly more women aged ≤44 years were HBeAg-positive compared to women ≥45 years (57.2% versus 27.5%, respectively, p108 copies mL: ≤44 years 46.0% vs ≥45 years 25.5%, respectively; p CONCLUSIONS: Women of childbearing age with CHB are more likely to have high HBV viral load and HBeAg positivity than older women; this likelihood decreases with age. Maternal serological and virological status should therefore be established early in pregnancy, taking into account age and genotype, and a risk-reducing strategy implemented in any patient who is HBeAg positive and has a high viral load

CEA and CYFRA 21-1 as prognostic biomarker and as a tool for treatment monitoring in advanced NSCLC treated with immune checkpoint inhibitors

Aims: To assess prognostic value of pre-therapy carcinoembryonic antigen (CEA) and cytokeratin-19 fragments (CYFRA 21-1) blood levels in non-small cell lung cancer (NSCLC) patients treated with immune-checkpoint inhibitors (ICIs) and their early change as predictor of benefit. Materials and methods: This is a retrospective cohort study including patients with stage IIIB–IV NSCLC who received anti PD-1/PD-L1 in first or advanced lines of therapy in two institutions. A control cohort of patients treated only with chemotherapy has been enrolled as well. Results: A total of 133 patients treated with nivolumab or atezolizumab were included in the test set, 74 treated with pembrolizumab first line in the validation set and 89 in the chemotherapy only cohort. CYFRA 21-1 >8 ng/mL was correlated with overall survival (OS) in the test set, validation set and in univariate and multivariate analysis (pooled cohort hazard ratio (HR) 1.90, 95% confidence interval (CI) 1.24–2.93, p 0.003). Early 20% reduction after the third cycle was correlated with OS for CEA (HR 0.12; 95% CI 0.04–0.33; p < 0.001), and for CYFRA 21-1 (HR 0.19; 95% CI 0.07–0.55; p 0.002) Conclusions: CYFRA 21-1 pre-therapy assessment provides clinicians with relevant prognostic information about patients treated with ICI. CEA and CYFRA 21-1 repeated measures could be useful as an early marker of benefit

The (p,n) Reaction at Intermediate Energies with the Isotopes of Oxygen (16,17,18-O) and 9-Be as Part of a Unified Approach to the Study of These Nuclei

This work was supported by the National Science Foundation Grant NSF PHY 78-22774 A02 & A03 and by Indiana Universit