4,567 research outputs found
Fractal Conductance Fluctuations of Classical Origin
In mesoscopic systems conductance fluctuations are a sensitive probe of
electron dynamics and chaotic phenomena. We show that the conductance of a
purely classical chaotic system with either fully chaotic or mixed phase space
generically exhibits fractal conductance fluctuations unrelated to quantum
interference. This might explain the unexpected dependence of the fractal
dimension of the conductance curves on the (quantum) phase breaking length
observed in experiments on semiconductor quantum dots.Comment: 5 pages, 4 figures, to appear in PR
Information-theoretic determination of ponderomotive forces
From the equilibrium condition applied to an isolated
thermodynamic system of electrically charged particles and the fundamental
equation of thermodynamics () subject
to a new procedure, it is obtained the Lorentz's force together with
non-inertial terms of mechanical nature. Other well known ponderomotive forces,
like the Stern-Gerlach's force and a force term related to the Einstein-de
Haas's effect are also obtained. In addition, a new force term appears,
possibly related to a change in weight when a system of charged particles is
accelerated.Comment: 10 page
Evolutionary advantages of adaptive rewarding
Our wellbeing depends as much on our personal success, as it does on the
success of our society. The realization of this fact makes cooperation a very
much needed trait. Experiments have shown that rewards can elevate our
readiness to cooperate, but since giving a reward inevitably entails paying a
cost for it, the emergence and stability of such behavior remain elusive. Here
we show that allowing for the act of rewarding to self-organize in dependence
on the success of cooperation creates several evolutionary advantages that
instill new ways through which collaborative efforts are promoted. Ranging from
indirect territorial battle to the spontaneous emergence and destruction of
coexistence, phase diagrams and the underlying spatial patterns reveal
fascinatingly reach social dynamics that explains why this costly behavior has
evolved and persevered. Comparisons with adaptive punishment, however, uncover
an Achilles heel of adaptive rewarding that is due to over-aggression, which in
turn hinders optimal utilization of network reciprocity. This may explain why,
despite of its success, rewarding is not as firmly weaved into our societal
organization as punishment.Comment: 14 pages, 8 figures; accepted for publication in New Journal of
Physic
Magnetic Resonance Imaging Target Fusion Biopsy vs. Transrectal Ultrasound-Guided Biopsy - A Comparative Study of ISUP Score Upgrading Risk in the Final Radical Prostatectomy Specimen
Objectives: The aim of this study was to com-pare the risk of International Society of Urological Pathology (ISUP) score upgrading between magnetic resonance imaging targeted fusion biopsy (MRI-TB) and tran-srectal ultrasound-guided biopsy (TRUS-B) in the final radical prostatectomy (RP) specimen pathological report.
Materials and methods: This retrospective single center study included 51 patients with prostate cancer (PCa) diagnosed with MRI-TB and 83 patients diagnosed with TRUS-B between October/2019 and July/2021. We compared the rates of ISUP score upgrading between both groups after robotic-assisted radi-cal prostatectomy (RARP) and the specific transition of each ISUP score based on biopsy modality. The rate of ISUP score concordance and downgrading were also assessed. To define the intra and interobserver concordance for each ISUP score in biopsy and RP specimen for each biopsy modality, the Cohen's Kappa coefficient was calculated. ISUP scores and biopsy modal-ity were selected for multivariate analysis and a logistic regres-sion model was built to provide independent risk factors of ISUP score upgrading.
Results: The difference of the rate of upgrading between MRI-TB group and TRUS-B group was statistically significant (p = 0.007) with 42.2% of patients of TRUS-B group experiencing an upgrade in their ISUP score while only 19.6% in MRI-TB group. Concordance and downgrading rates did not statistically differ between the two groups. Strength of concordance using Cohen's Kappa coefficient was fair in both groups but higher in MRI-TB group (TRUS-B group k = 0.230; p < 0.001; concordance: 47%vs. MRI/TB group k = 0.438; p < 0.001; concordance: 62.7%). Biopsy modality and ISUP 1 on biopsy were independent predic-tors of ISUP upgrading after RP.
Conclusions: MRI-TB is highly accurate with lower risk of PCa upgrading after RP than TRUS-B. Patients with ISUP 1 on biopsy have greater susceptibility to upgrading their ISUP score.info:eu-repo/semantics/publishedVersio
The Role of Accessory Obturator Arteries in Prostatic Arterial Embolization
In 9 of 491 patients (1.8%) who underwent prostatic arterial embolization (PAE) for benign prostatic hyperplasia from March 2009-November 2013, prostatic arteries arose from the external iliac artery via an accessory obturator artery (AOA). Computed tomography angiography performed before the procedure identified the variant and allowed planning before the procedure. The nine AOAs were catheterized from a contralateral femoral approach. Bilateral PAE was technically successful in the nine patients. There was a mean decrease in international prostate symptom score of 6.5 points and a mean prostate volume reduction of 15.1% (mean follow-up, 4.8 mo) in the nine patients
Prostatic Artery Embolization in the Treatment of Benign Prostatic Hyperplasia: Short and Medium Follow-Up
To evaluate the short and mid-term results of prostatic artery embolization in patients with benign prostatic embolization. Retrospective study between March 2009 and June 2011 with 103 patients (mean age 66.8 years, 50-85) that met our inclusion criteria with symptomatic benign prostatic hyperplasia. The clinical outcome was evaluated by the International Prostate Symptom Score (IPSS), quality of life (QoL), International Index of Erectile Function, prostate volume (PV), prostate-specific antigen (PSA), peak urinary flow (Q(max)), and post-void residual volume (PVR) measurements at 3 and 6 months, 1 year, 18 months, and 2 years after PAE and comparison with baseline values was made. Technical and clinical successes, as well as poor clinical outcome definitions, were previously defined. In this review, we evaluate the short and mid-term clinical outcomes and morbidity of patients treated only with non-spherical polyvinyl alcohol. Six months after the procedure, the PV decreased about 23%, IPSS changed to a mean value of 11.95 (almost 50% reduction), the QoL improved slightly more than 2 points, the Q(max) changed to a mean value of 12.63mL/s, the PVR underwent a change of almost half of the baseline value, and the PSA decreased about 2.3ng/mL. In the mid-term follow-up and comparing to the baseline values, we still assisted to a reduction in PV, IPSS, QoL, PVR, and PSA, and an increase in Q(max). Prostatic Artery Embolization is a safe procedure with low morbidity that shows good short- and mid-term clinical outcome in our institution
Embolisation of Prostatic Arteries as Treatment of Moderate to Severe Lower Urinary Symptoms (LUTS) Secondary to Benign Hyperplasia: Results of Short- and Mid-Term Follow-Up
OBJECTIVES: To evaluate the short- and medium-term results of prostatic arterial embolisation (PAE) for benign prostatic hyperplasia (BPH).
METHODS: This was a prospective non-randomised study including 255 patients diagnosed with BPH and moderate to severe lower urinary tract symptoms after failure of medical treatment for at least 6 months. The patients underwent PAE between March 2009 and April 2012. Technical success is when selective prostatic arterial embolisation is completed in at least one pelvic side. Clinical success was defined as improving symptoms and quality of life. Evaluation was performed before PAE and at 1, 3, 6 and every 6 months thereafter with the International Prostate Symptom Score (IPSS), quality of life (QoL), International Index of Erectile Function (IIEF), uroflowmetry, prostatic specific antigen (PSA) and volume. Non-spherical polyvinyl alcohol particles were used.
RESULTS: PAE was technically successful in 250 patients (97.9 %). Mean follow-up, in 238 patients, was 10 months (range 1-36). Cumulative rates of clinical success were 81.9 %, 80.7 %, 77.9 %, 75.2 %, 72.0 %, 72.0 %, 72.0 % and 72.0 % at 1, 3, 6, 12, 18, 24, 30 and 36 months, respectively. There was one major complication.
CONCLUSIONS: PAE is a procedure with good results for BPH patients with moderate to severe LUTS after failure of medical therapy.
KEY POINTS: • Prostatic artery embolisation offers minimally invasive therapy for benign prostatic hyperplasia. • Prostatic artery embolisation is a challenging procedure because of vascular anatomical variations. • PAE is a promising new technique that has shown good results
Cellulose nanofibers produced from banana peel by chemical and enzymatic treatments: characterization and in vitro cytotoxicity assessment
info:eu-repo/semantics/publishedVersio
Effective Non-Hermitian Hamiltonians for Studying Resonance Statistics in Open Disordered Systems
We briefly discuss construction of energy-dependent effective non-hermitian
hamiltonians for studying resonances in open disordered systemsComment: Latex, 20 pages, 1 fig. Expanded version of a talk at the Workshop on
Pseudo-Hermitian Hamiltonians in Quantum Physics IX, June 21-24 2010,
Zhejiang University, Hangzhou, China. Accepted for publication in the
Internationa Journal of Theoretical Physics (Springer Verlag
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