36 research outputs found
Features of gravitational waves in higher dimensions
There are several fundamental differences between four-dimensional and
higher-dimensional gravitational waves, namely in the so called braneworld
set-up. One of them is their asymptotic behavior within the Cauchy problem.
This study is connected with the so called Hadamard problem, which aims at the
question of Huygens principle validity. We investigate the effect of braneworld
scenarios on the character of propagation of gravitational waves on FRW
background.Comment: to appear in ERE09 proceeding
Our first clinical experience with radiosynoviorthesis by means of 166Ho-holmium-boro-macroaggregates
BACKGROUND: In this paper, we evaluate the therapeutic and
adverse effects of the application of 166-holmium-boro-macroaggregates
(HMBA) in radiosynovectomy (RSO) of the knees.
We assessed the efficacy and safety of 166Ho-HBMA in a prospective
clinical trial in patients suffering from chronic synovitis.
MATERIAL AND METHODS: An effective component of radiopharmaceutical
166Ho-boro-macroaggregates is radionuclide
166Ho which has both β-emission and γ-emission. The physical
half-life time of 166Ho is 26.8 hours. After application of the radiopharmaceutical
into a joint cavity, the effect of β-emission
causes radiation necrosis of pathologically changed (inflamed)
synovial membrane. From 15th April 2005, we have started RSO
of knees by means of new radiopharmaceutical 166Ho-boro-macroaggregates
in patients with gonarthrosis, rheumatoid arthritis,
chronic synovitis, psoriatic arthritis, gout arthropathy. Seventeen
intra-articular injections were performed in fifteen patients
receiving a mean activity of 972 MBq (range: 904-1057 MBq)
166Ho-HMBA. The patients were hospitalized for three days. Side
effects were evaluated during hospital stay and after 6-8 weeks.
Static scintigraphy of knee joints and measurements of blood
radioactivity were performed. Therapeutic effects were evaluated
after 6-8 weeks.
RESULTS: In 2 hours and 2 days after application, we proved,
by means of knee and inguinal scintigraphy, only insignificant
radiopharmaceutical leakage from the joint cavity to the inguinal
lymph nodes in four patients. In treated patients, no serious
adverse effects occurred. Nine patients were without complaints;
4 patients had slight knee exsudation and 2 patients had great
exsudation. Therapeutic effects after 6-8 weeks were as follows:
2 patients were without pain, 9 with lower pain, 3 with the
same pain and 1 patient with increased pain. Joint motion was
improved in 7 patients, remained the same in 7 patients and
was impaired in 1 patient. Analgesics consumption was lower
in 5 patients, the same in 9 patients and greater in 1 patient.
Knee exsudation was absent in 2 patients, lower in 4 patients,
the same in 6 patients and greater in 3 patients.
CONCLUSIONS: We proved only insignificant radiopharmaceutical
leakage from the joint cavity to the inguinal lymph nodes.
Six patients had early slight or great radiation synovitis. The
possible cause could be rather high applicated activity. One
can take into consideration its reduction. Therapeutic effects
can be precisely evaluated after a longer time interval than was
possible for us (6-8 weeks after RSO). 166Ho-boro-macroaggregates
can extend the scale of clinically used radiopharmaceuticals
for RSO.
This paper is presented in the scope of the first stage of clinical
evaluation of synovectomy application of holmium-boro-macroaggregates
Local Optical Probe of Motion and Stress in a multilayer graphene NEMS
Nanoelectromechanical systems (NEMSs) are emerging nanoscale elements at the
crossroads between mechanics, optics and electronics, with significant
potential for actuation and sensing applications. The reduction of dimensions
compared to their micronic counterparts brings new effects including
sensitivity to very low mass, resonant frequencies in the radiofrequency range,
mechanical non-linearities and observation of quantum mechanical effects. An
important issue of NEMS is the understanding of fundamental physical properties
conditioning dissipation mechanisms, known to limit mechanical quality factors
and to induce aging due to material degradation. There is a need for detection
methods tailored for these systems which allow probing motion and stress at the
nanometer scale. Here, we show a non-invasive local optical probe for the
quantitative measurement of motion and stress within a multilayer graphene NEMS
provided by a combination of Fizeau interferences, Raman spectroscopy and
electrostatically actuated mirror. Interferometry provides a calibrated
measurement of the motion, resulting from an actuation ranging from a
quasi-static load up to the mechanical resonance while Raman spectroscopy
allows a purely spectral detection of mechanical resonance at the nanoscale.
Such spectroscopic detection reveals the coupling between a strained
nano-resonator and the energy of an inelastically scattered photon, and thus
offers a new approach for optomechanics
The IDENTIFY study: the investigation and detection of urological neoplasia in patients referred with suspected urinary tract cancer - a multicentre observational study
Objective
To evaluate the contemporary prevalence of urinary tract cancer (bladder cancer, upper tract urothelial cancer [UTUC] and renal cancer) in patients referred to secondary care with haematuria, adjusted for established patient risk markers and geographical variation.
Patients and Methods
This was an international multicentre prospective observational study. We included patients aged ≥16 years, referred to secondary care with suspected urinary tract cancer. Patients with a known or previous urological malignancy were excluded. We estimated the prevalence of bladder cancer, UTUC, renal cancer and prostate cancer; stratified by age, type of haematuria, sex, and smoking. We used a multivariable mixed-effects logistic regression to adjust cancer prevalence for age, type of haematuria, sex, smoking, hospitals, and countries.
Results
Of the 11 059 patients assessed for eligibility, 10 896 were included from 110 hospitals across 26 countries. The overall adjusted cancer prevalence (n = 2257) was 28.2% (95% confidence interval [CI] 22.3–34.1), bladder cancer (n = 1951) 24.7% (95% CI 19.1–30.2), UTUC (n = 128) 1.14% (95% CI 0.77–1.52), renal cancer (n = 107) 1.05% (95% CI 0.80–1.29), and prostate cancer (n = 124) 1.75% (95% CI 1.32–2.18). The odds ratios for patient risk markers in the model for all cancers were: age 1.04 (95% CI 1.03–1.05; P < 0.001), visible haematuria 3.47 (95% CI 2.90–4.15; P < 0.001), male sex 1.30 (95% CI 1.14–1.50; P < 0.001), and smoking 2.70 (95% CI 2.30–3.18; P < 0.001).
Conclusions
A better understanding of cancer prevalence across an international population is required to inform clinical guidelines. We are the first to report urinary tract cancer prevalence across an international population in patients referred to secondary care, adjusted for patient risk markers and geographical variation. Bladder cancer was the most prevalent disease. Visible haematuria was the strongest predictor for urinary tract cancer