Geometry of mixed states for a q-bit and the quantum Fisher information tensor

After a review of the pure state case, we discuss from a geometrical point of view the meaning of the quantum Fisher metric in the case of mixed states for a two-level system, i.e. for a q-bit, by examining the structure of the fiber bundle of states, whose base space can be identified with a co-adjoint orbit of the unitary group. We show that the Fisher Information metric coincides with the one induced by the metric of the manifold of SU(2), i.e. the 3-dimensional sphere $S^3$, when the mixing coefficients are varied. We define the notion of Fisher Tensor and show that its anti-symmetric part is intrinsically related to the Kostant Kirillov Souriau symplectic form that is naturally defined on co-adjoint orbits, while the symmetric part is nontrivially again represented by the Fubini Study metric on the space of mixed states, weighted by the mixing coefficients.Comment: 20 pages; Abstract and Introduction modified, references added. Final published versio

Efficacy of hormonal suppression in a patient with chyluria due to lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare lung disease affecting almost exclusively young women, characterised by abnormal proliferation of atypical smooth muscle cells. We describe a young woman presenting with chyluria secondary to the presence of a large retroperitoneal lymphangioleiomyoma. Immunohistochemical analysis revealed HMB45-negative LAM cells (HMB45 staining is absent only in rare cases) expressing low levels of estrogen receptors. Estrogen suppressive treatment with triptoreline, a synthetic analogue of Gn-RH, resulted in dramatic reduction of the retroperitoneal mass size. The role of estrogens in the pathogenesis of LAM remains poorly understood, and hormonal therapy is still debated, but this case suggests that at least in some LAM patients, possibly those with HMB45-negative disease and estrogen receptor expression, hormonal therapy may be effective in controlling the disease process

BV equivalence with boundary

An extension of the notion of classical equivalence of equivalence in the Batalin–Vilkovisky (BV) and Batalin–Fradkin–Vilkovisky (BFV) frameworks for local Lagrangian field theory on manifolds possibly with boundary is discussed. Equivalence is phrased in both a strict and a lax sense, distinguished by the compatibility between the BV data for a field theory and its boundary BFV data, necessary for quantisation. In this context, the first- and second-order formulations of nonabelian Yang–Mills and of classical mechanics on curved backgrounds, all of which admit a strict BV–BFV description, are shown to be pairwise equivalent as strict BV–BFV theories. This in particular implies that their BV complexes are quasi-isomorphic. Furthermore, Jacobi theory and one-dimensional gravity coupled with scalar matter are compared as classically equivalent reparametrisation-invariant versions of classical mechanics, but such that only the latter admits a strict BV–BFV formulation. They are shown to be equivalent as lax BV–BFV theories and to have isomorphic BV cohomologies. This shows that strict BV–BFV equivalence is a strictly finer notion of equivalence of theories

On the geometry of mixed states and the Fisher information tensor

In this paper, we will review the co-adjoint orbit formulation of finite dimensional quantum mechanics, and in this framework, we will interpret the notion of quantum Fisher information index (and metric). Following previous work of part of the authors, who introduced the definition of Fisher information tensor, we will show how its antisymmetric part is the pullback of the natural Kostant-Kirillov-Souriau symplectic form along some natural diffeomorphism. In order to do this, we will need to understand the symmetric logarithmic derivative as a proper 1-form, settling the issues about its very definition and explicit computation. Moreover, the fibration of co-adjoint orbits, seen as spaces of mixed states, is also discussed.Comment: 27 pages; Accepted Manuscrip

Looking for hotspots of marine metacommunity connectivity: a methodological framework

Seascape connectivity critically affects the spatiotemporal dynamics of marine metacommunities. Understanding how connectivity patterns emerge from physically and biologically-mediated interactions is therefore crucial to conserve marine ecosystem functions and biodiversity. Here, we develop a set of biophysical models to explore connectivity in assemblages of species belonging to a typical Mediterranean community (Posidonia oceanica meadows) and characterized by different dispersing traits. We propose a novel methodological framework to synthesize species-specific results into a set of community connectivity metrics and show that spatiotemporal variation in magnitude and direction of the connections, as well as interspecific differences in dispersing traits, are key factors structuring community connectivity. We eventually demonstrate how these metrics can be used to characterize the functional role of each marine area in determining patterns of community connectivity at the basin level and to support marine conservation planning

Does technetium-99m diethylenetriaminepentaacetate clearance predict the clinical course of idiopathic pulmonary fibrosis?

Clearance of inhaled technetium-99m diethylenetriaminepentaacetate (99mTc-DTPA) is a potential indicator of disease activity and progression in idiopathic pulmonary fibrosis (IPF). The objective of the present study was to evaluate the prognostic value of 99mTc-DTPA scans in IPF. A total of 22 patients (18 males), aged 33 to 80 years with IPF were followed for six to 20 months (mean 13 months). At diagnosis, high resolution computed tomography (HRCT) scans showed a honeycomb pattern with bibasilar reticular opacities in all cases. At T0 (diagnosis) and T1 (follow-up), each patient had pulmonary function tests (forced vital capacity, diffusing capacity of the lung for carbon monoxide and partial arterial O2 pressure), extension of fibrosis evaluated by HRCT visual score and 99mTc-DTPA lung clearance. Results at T0 and T1 were compared, taking into account the whole population and patients with relatively fast and slow 99mTc-DTPA wash-out. 99mTc-DTPA clearance did not show any significant correlation with functional tests or HRCT score. These findings indicate that clearance of inhaled 99mTc-DTPA is not of value in following the progress of IPF

Complications After Systematic, Random and Image-guided Prostate Biopsy

CONTEXT: Prostate biopsy (PB) represents the gold standard method to confirm the presence of cancer. In addition to traditional random or systematic approaches, a magnetic resonance imaging (MRI)-guided technique has been introduced recently. OBJECTIVE: To perform a systematic review of complications after transrectal ultrasound (TRUS)-guided, transperineal, and MRI-guided PB. EVIDENCE ACQUISITION: We performed a systematic literature search of Web of Science, Embase, and Scopus databases up to October 2015, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Complications and mortality following random, systematic, and image-guided PBs were reviewed. Eighty-five references were included. EVIDENCE SYNTHESIS: The most frequent complication after PB was minor and self-limiting bleeding (hematuria and hematospermia), regardless of the biopsy approach. Occurrence of rectal bleeding was comparable for traditional TRUS-guided and image-guided PBs. Almost 25% of patients experienced lower urinary tract symptoms, but only a few had urinary retention, with higher rates after a transperineal approach. Temporary erectile dysfunction was not negligible, with a return to baseline after 1-6 mo. The incidence of infective complications is increasing, with higher rates among men with medical comorbidities and older age. Transperineal and in-bore MRI-targeted biopsy may reduce the risk of severe infectious complications. Mortality after PB is uncommon, regardless of biopsy technique. CONCLUSIONS: Complications after PB are frequent but often self-limiting. The incidence of hospitalization due to severe infections is continuously increasing. The patient's general health status, risk factors, and likelihood of antimicrobial resistance should be carefully appraised before scheduling a PB. PATIENT SUMMARY: We reviewed the variety and incidence of complications after prostate biopsy. Even if frequent, complications seldom represent a problem for the patient. The most troublesome complications are infections. To minimize this risk, the patient's medical condition should be carefully evaluated before biopsy

Comparison between "In-bore" MRI guided prostate biopsy and standard ultrasound guided biopsy in the patient with suspicious prostate cancer: Preliminary results.

OBJECTIVES: To evaluate the detection rate of prostate cancer (PCa) in patients who underwent to "in bore" Magnetic Resonance Imaging -guided prostate (MRI-GB) biopsy compared to the standard transrectal ultrasound guided prostate biopsy (TRUS-GB). MATERIALS AND METHODS: Between January 2017 and March 2015 a cohort of 39 consecutive patients was prospectively enrolled. All the patients underwent an "in-bore" guided MRI prostatic biopsy and subsequently ultrasound-guided standard prostate biopsy. RESULTS: Median age of patients was 65.5 years (SD \ub1 6.6), median total PSA serum level was 6.6 ng/ml (SD \ub1 4.1), median prostate total volume was 51.1 cc (SD \ub1 26.7). Thirty of 39 (76.9%) were biopsy-na\uefve patients while 7/39 (17.9%) had at least one previous negative random TRUS-GB; 2/39 (5.1%) patients were already diagnosed as PCa and were on active surveillance. In 18/39 (53.8%) men Pca was diagnosed; as regards the MRI-GB results related to the PI-RADS score, biopsies of PIRADS 3 lesions were positive in 5/18 cases (27.8%), while the number of positive cases of PI-RADS 4 and 5 lesions was 7/11 (63.6%) and 6/10 (60%)respectively. At the histological examination, 4/39 (10.3%) had a PCa ISUP grade group 1, 11/39 (28.2%) had a ISUP 2, 6/39(15.4%) had a ISUP grade group 3 and 2/39 (5.1%) had a ISUP 4-5. CONCLUSIONS: MRI-GB represents a promising technique that may offer some of advantages compared to standard systematic TRUSGB. Our preliminary experience in MRI-GB resulted safe and feasible and represents a viable procedure for the diagnosis and characterization of PCa

T-L technique for HoLEP: perioperative outcomes of a large single-centre series

Introduction: The aim of this article was to describe, step-by-step, an original technique (T-L technique) in a single centre series of patients who underwent holmium laser enucleation of the prostate (HoLEP) for symptomatic benign prostatic hyperplasia and analyze perioperative outcomes. Material and methods: We retrospectively analyzed data of 567 patients who underwent HoLEP. The T-L technique consists of a series of incisions used as landmarks, performed at the beginning of the procedure before enucleation. Two T-shape incisions are performed at the level of bladder neck (at the 5-7 and 12 o'clock positions); two L-shape incisions are performed at the level of verumontanum, bilaterally, to mark the apex and to limit the sphincter. Another T-shape incision is performed on the bladder neck at the 12 o'clock position posterior to the level of verumontanum. Results: The median operative time (OT) was 80 minutes (IQR 64-105); 50 minutes (IQR 35-70) and 15 minutes (IQR 10-20) for enucleation and the morcellation phase, respectively. Conversion to transurethral resection of the prostate (TURP) was necessary in 3/567 (0.6%) patients. Intraoperative complications occurred in 3.4% of cases, capsule perforation occurred in 12/567 (2%) of cases, while bladder perforation during morcellation occurred in 8/567 (1.4%) of cases. Postoperative complications were observed in 20/567 (3.5%) of patients. Specifically, grade 1-2 occurred in 19/567 (3.3%) and grade 3 was recorded in 1/567 (0.2%). Conclusions: The T-L technique for HoLEP is safe and reproducible with a low rate of perioperative complications. The positioning of some landmarks before enucleation allows for the better orientation during enucleation and could be very useful in case of large prostates

Mini-invasive robotic assisted pyelolithotomy: Comparison between the transperitoneal and retroperitoneal approach.

OBJECTIVE: To compare the retroperitoneal with the transperitoneal approach in a series of patients underwent to robotic-assisted pyelolithotomy (RP). MATERIALS AND METHODS: From January 2015 to December 2018 we evaluated 20 patients subjected to robotic pyelolithotomy; 11 patients were treated with retroperitoneal approach (RRP) and 9 with transperitoneal approach (TRP). For each patient intra and perioperative data were recorded: operative time (OT), blood loss (BL), length of hospital stay (LOS), stone clearance, post-operative complications and time to remove the drain. The presence of stone fragments < 4 mm was considered as stone free rate. RESULTS: The principal stone burden was greater in the TRP group than in the RRP group (48 ± 10 mm vs 32 ± 14 mm, p = 0.12). Preoperative hydronephrosis was present in 7 (64%) patients in RRP group and a mild hydronephrosis in 3 of TRP group (p = 0.04). The average operative time was higher in the RRP group than in the TRP group (203 ± 45 min vs 137 ± 31 min, p = 0.002). The average blood loss was 305 ± 175 ml in the RRP group versus 94 ± 104 ml in the TRP group (p = 0.005). The stone free rate was similar between the two groups, 36% (4 patients) in the RRP group and 44% (4 patients) in the TRP (p = 0.966). CONCLUSIONS: RP appears to be a safe and effective minimally invasive treatment for some patients with renal staghorn calculi or urinary tract malformations. The TRP may give lower operative time and better results in terms of blood loss and length of hospital stay