Design and application of magneto-rheological fluid

Magneto-Rheological Fluid (MRF) technology is an old “newcomers” coming to the market at high speed. Various industries including the automotive industry are full of potential MRF applications. Magneto-Rheological Fluid technology has been successfully employed already in various low and high volume applications. A structure based on MRF might be the next generation in design for products where power density, accuracy and dynamic performance are the key features. Additionally, for products where is a need to control fluid motion by varying the viscosity, a structure based on MRF might be an improvement in functionality and costs. Two aspects of this technology, direct shear mode (used in brakes and clutches) and valve mode (used in dampers) have been studied thoroughly and several applications are already present on the market. Excellent features like fast response, simple interface between electrical power input and mechanical power output, and precise controllability make MRF technology attractive for many applications. This paper presents the state of the art of an actuator with a control arrangement based on MRF technology. The study shows that excellent features like fast response, simple interface between electrical power input and the mechanical power output, and controllability make MRF the next technology of choice for many applications

SU(2) Cosmological Solitons

We present a class of numerical solutions to the SU(2) nonlinear $\sigma$-model coupled to the Einstein equations with cosmological constant $\Lambda\geq 0$ in spherical symmetry. These solutions are characterized by the presence of a regular static region which includes a center of symmetry. They are parameterized by a dimensionless ``coupling constant'' $\beta$, the sign of the cosmological constant, and an integer ``excitation number'' $n$. The phenomenology we find is compared to the corresponding solutions found for the Einstein-Yang-Mills (EYM) equations with positive $\Lambda$ (EYM$\Lambda$). If we choose $\Lambda$ positive and fix $n$, we find a family of static spacetimes with a Killing horizon for $0 \leq \beta < \beta_{max}$. As a limiting solution for $\beta = \beta_{max}$ we find a {\em globally} static spacetime with $\Lambda=0$, the lowest excitation being the Einstein static universe. To interpret the physical significance of the Killing horizon in the cosmological context, we apply the concept of a trapping horizon as formulated by Hayward. For small values of $\beta$ an asymptotically de Sitter dynamic region contains the static region within a Killing horizon of cosmological type. For strong coupling the static region contains an ``eternal cosmological black hole''.Comment: 20 pages, 6 figures, Revte

45. Impact of Hb level during postoperative radiotherapy of patients with larynx cancer

AimAssessment the influence of low level of Hgb on the locoregional outcome of postoperative radiotherapy patients with advanced cancer of larynx.Material and methodsAn retrospective analysis of two hundred fifty four patients with larynx carcinoma with stage III or IV squamous cell carcinoma of larynx who were treated between January 1993 and December 1996 was performed. Postoperative radiotherapy was performed in coventional way to total dose of 60 Gy, 5 times a week. Of 254 patients, 86 patients (34%) were considered to have a low level of hemoglobin (below 13 g/dl) prior the beginning of radiotherapy and 56 patients (22%) at the end of treatment. We have noted also 38 patients (15%) of 254 patients, with deacresing hemoglobin level during treatment higher than 1 g/dl.ResultsNo impact on outcome of treatment was observed in the group of patients with low level of Hgb before irradiation. Inrease of locoregional failure of postoperative radiotherapy was noted in group of patients with Hgb level at the end of irradiation below 13 g/dl (p = 0,004) and also in group of patients with decreasing of Hgb level during treatment (p = 0,038).ConclusionsLow Hgb levels at the end of postoperative irradiation and decreasing during irradiation were associated with a statistically significant an increase in locoregional failure of patients with advanced carcinoma of larynx

58. Influence of total time of surgery and postoperative radiotherapy on the outcome patients with advanced laryngeal carcinoma

AimTo evaluate influence of total time of combined treatment on locoregional outcome of treatment in group patients with larynx cancer.Material/MethodsWe performed retrospective analysis of 254 patients with with stage III or IV squamous cell carcinoma of larynx who were treated between 1993 and 1996. There were 236 men, 18 women, median age was 56.3 years. Surgery consisted of total laryngectomy and elective/selective neck dissection. Patients postoperativly were irradiated in coventional way with total dose of 60 Gy. We used shrinking field technique with lateral opposed photon fields to tumor bed and upper-mid neck nodes. Supraclavicular regions (lower neck lymph nodes) were treated with an anterior field. Total time of combined treatment (from the surgery to the end of radiotherapy) was an average 92 days (range, 65–131 days). The interval between surgery and the beginning of radiotherapy was an average 45 days (range, 22–78 days) and time of irradiation was an average 45 day (range, 40–74 days).ResultsProlongation overall time of combined treatment beyond 90 days is strongly correlated with decreasing of locoregional outcome of treatment (p=0.00036). Also decreasing in outcome of treatment was noted when interval time between surgery and beginning of radiotherapy was more than 50 days (p=0.022) and when the time of irradiation was longer than 44 days (p=0.0026).ConclusionsDecreasing of total time of combined treatment (surgery and postoperative radiotherapy) is crucial in patients with advanced cancer of larynx

13. Immunogenetherapy combined with brain metastases irradiation in melanoma patients

AimsTo assess toxicity and results of melanoma brain metastases irradiation in patients treated with genetically modified tumour vaccine.Materials/methodsA group of 45 melanoma stage IV (AJCC) patients was treated with vaccine consisted of autologic melanoma cells admixed with allogeneic cells modified with IL-6 and slL-6R genes. During the treatment 14 patients developed symptoms of brain metastases. 5 patients had solitary metastases, 9 multiple lesions. 4 patients with single metastasis were treated surgically. All 14 patients were irradiated with the doses 30–39 Gy, using 3 Gy/fracion, 5 fractions/week. Toxicity of cranial irradiation (clinically, CT) and clinical results (CT, survival) were evaluated. Immunological cellular responses were assessed in vitro.ResultsAcute effects of irradiation were tolerable and manageable using standard dexamethasone treatment. There was no radiation encephalopathy or radiation necrosis. In 7/14 patients stabilization or partial remission of brain lesions was observed. Overall survival measured from brain metastases diagnosis ranged from 2 to 21 months (2 patients are still alive), median survival was 316 days. In 4 treated patients radiation enhanced immune responses to the vaccine.ConclusionsPalliative cranial irradiation is well tolerated by patients treated with novel systemic approaches such as immunogene therapy, relives symptoms and may extend survival. Radiation of metastases modulates immune responses to melanoma cells

Denosumab for the prevention of skeletal complications in metastatic castration-resistant prostate cancer: comparison of skeletal-related events and symptomatic skeletal events

Abstract Background In a phase III trial in patients with castration-resistant prostate cancer (CRPC) and bone metastases, denosumab was superior to zoledronic acid in reducing skeletal-related events (SREs; radiation to bone, pathologic fracture, surgery to bone, or spinal cord compression). This study reassessed the efficacy of denosumab using symptomatic skeletal events (SSEs) as a prespecified exploratory end point. Patients and methods Patients with CRPC, no previous bisphosphonate exposure, and radiographic evidence of bone metastasis were randomized to subcutaneous denosumab 120 mg plus i.v. placebo every 4 weeks (Q4W), or i.v. zoledronic acid 4 mg plus subcutaneous placebo Q4W during the blinded treatment phase. SSEs were defined as radiation to bone, symptomatic pathologic fracture, surgery to bone, or symptomatic spinal cord compression. The relationship between SSE or SRE and time to moderate/severe pain was assessed using the Brief Pain Inventory Short Form. Results Treatment with denosumab significantly reduced the risk of developing first SSE [HR, 0.78; 95% confidence interval (CI) 0.66–0.93; P = 0.005] and first and subsequent SSEs (rate ratio, 0.78; 95% CI 0.65–0.92; P = 0.004) compared with zoledronic acid. The treatment differences in the number of patients with SSEs or SREs were similar (n = 48 and n = 45, respectively). Among patients with no/mild pain at baseline, both SSEs and SREs were associated with moderate/severe pain development (P < 0.0001). Fewer patients had skeletal complications, particularly fractures, when defined as SSE versus SRE. Conclusion In patients with CRPC and bone metastases, denosumab reduced the risk of skeletal complications versus zoledronic acid regardless of whether the end point was defined as SSE or SRE

The results of salvage surgery combined with reirradiation in nodal recurrence of larynx cancer

The recurrence in the regional lymph nodes of patients after total laryngectomy and postoperative radiotherapy is a still serious therapeutic problem. The conditions that are altered following the combined primary treatment make it difficult to achieve satisfactory results of the second surgical treatment.The aim of our study was to evaluate the outcome of a salvage operation (lymphadenectomy) and reirradiation in 50 patients with recurrence in regional lymph nodes (rN). Beetwen 1991 and 1996, 650 patients with larynx carcinoma were treated in our institiutions. All patients during the primary irradiation received a total dose of about 60 Gy. In the case of regional recurrence (rN) patients had selective lymphadenectomy and reirradiation (total dose 40 Gy) when capsulae were found to be infiltrated. The survival rates were for 1, 2 and 3 years : 34 (68%), 22 (44%), only 9 (18%) respectivly. This strategy of a second combined treatment had a good tolerance level, without any unacceptable side effects (complications)

88. Comparison results of different strategies of radiotherapy in nasopharyngeal carcinoma

Aim: Evaluation results of radiotherapy in nasopharyngeal carcinoma in years; 1980–1990 (before CT era) vs 1991–1995.Material/methods: One hundred eighty eight patients treated in our centre were included in this analysis. Two groups of patients were distinguished: I-st – 128 patients (treated between 1980–1990) and II-nd – 60 (treated between 1991–1995). The possibilities of diagnosis and radiotherapy techniques were diffrent in both groups. In the II-nd group; the shrinking field technique, CT in diagnosis and target delineation and also higher total dose (mean 66 Gy) were applied.Results: For all patients 5-years disease free-survival was 30%. During follow-up the first two years were crucial, because 80% of failures occured. The causes of failures were as follow: the local recurrence (43%), metastases to lymph nodes (39%) and distant metastases (18%).Conclusions: Introducing CT into diagnosis and target delineation, the shrinking field technique and higher total dose of irradiation caused in improvement of results of radiotherapy in nasopharyngeal carcinoma

79. The effectivness of pain treatment with Strontium 89 in patient with osseous metastases

Aimof this study was to assessment of 89 Sr therapy as pain treatment modality in the group of patients with multiple bone metastases.Material and methodsFrom January 2000 to October 2000 in our center were treated 41 patients; 17 – prostate cancer and 24 – breast cancer patients. All patients had applied only one dose of 150 MBq of 89 Sr. Before and follow-up each patient has been evaluated; performance status according to the Karnofsky Scale and paro intensity according the VAS scale. We did not observe any clinical important haematological side effects. The ionisation dosemetric monitoring of the sources and the radioactive refuse were recorded. The radioactive refuse was storage in special container when the activity decreased to the background.ResultsWe noted relief of paro as follow:-“complete” 18 of 41 patients (8-prostate cancer, 10 – breast cancer),-“partial” 12 of 41 patients (3- prostate cancer, 9- breast cancer),-“no effect” 11 of 41 patients (6-prostate cancer, 5- breast cancer).ConclusionsWe suggest that therapy of painful multiple bone metastases with application of 89 Sr is effective nd safe

Randomized, Double-Blind, Placebo-Controlled Phase III Study of Tasquinimod in Men With Metastatic Castration-Resistant Prostate Cancer

PURPOSE: Tasquinimod, a novel oral therapy targeting the tumor microenvironment, significantly improved progression-free survival (PFS) in a randomized, placebo-controlled phase II trial in men with metastatic castration-resistant prostate cancer (mCRPC). This phase III study was conducted to confirm the phase II results and to detect an overall survival (OS) benefit. PATIENTS AND METHODS: Men with chemotherapy-naïve mCRPC and evidence of bone metastases were assigned (2:1) to receive tasquinimod once per day or placebo until progression or toxicity. The primary end point was radiographic PFS (rPFS; time from random assignment to radiologic progression or death) per Prostate Cancer Working Group 2 criteria and RECIST 1.1. The study had 99.9% power to detect an rPFS hazard ratio (HR) of 0.6 with a two-sided alpha error of .05 and 80% power to detect a target HR of 0.8 for OS, the key secondary end point. RESULTS: In all, 1,245 patients were randomly assigned to either tasquinimod (n = 832) or placebo (n = 413) between March 2011 and December 2012 at 241 sites in 37 countries. Baseline characteristics were balanced between groups: median age, 71 years; Karnofsky performance status ≥ 90%, 77.3%; and visceral metastases, 21.1%. Estimated median rPFS by central review was 7.0 months (95% CI, 5.8 to 8.2 months) with tasquinimod and 4.4 months (95% CI, 3.5 to 5.5 months) with placebo (HR, 0.64; 95% CI, 0.54 to 0.75; P < .001). Median OS was 21.3 months (95% CI, 19.5 to 23.0 months) with tasquinimod and 24.0 months (95% CI, 21.4 to 26.9 months) with placebo (HR, 1.10; 95% CI, 0.94 to 1.28; P = .25). Grade ≥ 3 adverse events were more frequent with tasquinimod (42.8% v 33.6%), the most common being anemia, fatigue, and cancer pain. CONCLUSION: In chemotherapy-naïve men with mCRPC, tasquinimod significantly improved rPFS compared with placebo. However, no OS benefit was observed