156 research outputs found
AdS/CFT correspondence via R-current correlation functions revisited
Motivated by realizing open/closed string duality in the work by Gopakumar
[Phys. Rev. D70:025009,2004], we study two and three-point correlation
functions of R-current vector fields in N=4 super Yang-Mills theory. These
correlation functions in free field limit can be derived from the worldline
formalism and written as heat kernel integrals in the position space. We show
that reparametrizing these integrals converts them to the expected AdS
supergravity results which are known in terms of bulk to boundary propagator.
We expect that this reparametrization corresponds to transforming open string
moduli parameterization to the closed string ones.Comment: 23 pages, v2: calculations clarified, references added, v3: sections
re-arranged with more explanations, 4 figures and an appendix adde
Enhancing legacy in palliative care: study protocol for a randomized controlled trial of Dignity Therapy focused on positive outcomes.
BackgroundDignity Therapy is a brief psychotherapy that can enhance a sense of legacy while addressing the emotional and existential needs of patients receiving hospice or palliative care. In Dignity Therapy, patients create a formalized "legacy" document that records their most cherished memories, their lessons learned in life, as well as their hopes and dreams for loved ones in the future. To date, this treatment has been studied for its impact on mitigating distress within hospice and palliative care populations and has provided mixed results. This study will instead focus on whether Dignity Therapy enhances positive outcomes in this population.Methods/designIn this study, 90 patients with cancer receiving hospice or palliative care will complete a mixed-methods randomized controlled trial of Dignity Therapy (n = 45) versus Supportive Attention (n = 45). The patients will be enrolled in the study for 3 weeks, receiving a total of six study visits. The primary outcomes examine whether the treatment will quantitatively increase levels of positive affect and a sense of life closure. Secondary outcomes focus on gratitude, hope, life satisfaction, meaning in life, resilience, and self-efficacy. Using a fixed, embedded dataset design, this study will additionally use qualitative interviews to explore patients' perceptions regarding the use of positive outcome measures and whether these outcomes are appropriately matched to their experiences in therapy.DiscussionDignity Therapy has shown mixed results when evaluating its impact on distress, although no other study to date has solely focused on the potential positive aspects of this treatment. This study is novel in its use of mixed methods assessments to focus on positive outcomes, and will provide valuable information about patients' direct experiences in this area.Trial registrationISRCTN91389194
Provenance and environmental risk of windblown materials from mine tailing ponds, Murcia, Spain
Atmospheric particulates play a vital role in the transport of potentially toxic metals, being an important exposure pathways of people to toxic elements, which is faster and can occur in a much larger scale than water, soil and biota transport. Windblown materials in abandoned tailing ponds have not been well examined. The objectives of this investigation were: to study the major physical and geochemical properties of the materials eroded by wind inside the tailing ponds, and to understand the relative contribution of different sources to its heavy metals concentration. Study area is located in Cartagena-La Union mining district (SE Spain), where metallic mining of Fe, Pb and Zn has been developed for more than 2500 years. Wind-eroded particulates were monthly collected at 3 different heights (20, 50, and 80 cm) from the ground for a period of a full year using 4 dust collectors. Four tailing samples and 4 surface soil samples from the surrounding hills were also taken. Dust, soil, and tailing samples were examined for pH, particle size distribution, electrical conductivity, calcium carbonate content, Pb, Cu, Zn, Cd, Mn, Co, Ni, Ti and Zr concentrations. The results indicated that very coarse textured, slightly saline, and almost neutral wind-eroded deposits were generated with a very high temporal variability throughout the year. They also showed that the concentration of Cd, Mn, Pb and Zn, in the dust samples is extraordinarily high (18, 1254, 1831, and 5747 mg kg-1 respectively), whereas Co, Ni, and Cu had concentrations into the range of background concentrations found in the Earth’s crust (3.8, 12, and 60 mg kg-1 respectively). Besides, the concentration of both categories of heavy metals in the dust samples was higher than that in tailing and less than that of the soils. The barren surfaces of tailing ponds and also the surface soils of the surrounding area seem to be the major contributors to the dust collected. Therefore, abandoned mines as well as their tailing ponds should be rehabilitated by proper technologies and then well stabilized and /or covered by appropriate plant vegetation to control the transfer, particularly by air, of environmentally hazardous materials to other areas.Este artículo fue financiado por las universidades Isfahan University of Technology y Shahrood University of Technology (Irán) a través de las estancias de los profesores Khademi y Abbaspour, así como por la empresa propietaria de los terrenos donde se realizó el estudio. Este artículo se desarrolló en la zona de estudio del proyecto CP-IP 213968-2 IRIS, financiado por la European Union FP7, y la Dirección General de Industria, Energía y Minas de la Región de Murcia
Prognostic value of T1 substaging on oncological outcomes in patients with non-muscle-invasive bladder urothelial carcinoma : a systematic literature review and meta-analysis
Non-Supersymmetric Attractors in Gravities
We investigate the attractor mechanism for spherically symmetric extremal
black holes in a theory of general gravity in 4-dimensions, coupled to
gauge fields and moduli fields. For the general theory, we look for
solutions which are analytic near the horizon, show that they exist and enjoy
the attractor behavior. The attractor point is determined by extremization of
an effective potential at the horizon. This analysis includes the backreaction
and supports the validity of non-supersymmetric attractors in the presence of
higher derivative interactions. To include a wider class of solutions, we
continue our analysis for the specific case of a Gauss-Bonnet theory which is
non-topological, due to the coupling of Gauss-Bonnet terms to the moduli
fields. We find that the regularity of moduli fields at the horizon is
sufficient for attractor behavior. For the non-analytic sector, this regularity
condition in turns implies the minimality of the effective potential at the
attractor point.Comment: 19 pages, 2 figure
Branes in Time-Dependent Backgrounds and AdS/CFT Correspondence
We study supergravity solutions of Dp-branes in the time-dependent orbifold
background. We show that worldvolume theories decouple from the bulk gravity
for p less than six. Along AdS/CFT correspondence, these solutions could
provide the gravity description of noncommutative field theory with
time-dependent noncommutative parameter. Type II NS5-brane (M5-brane) in the
presence of RR n-form for n=0,..., 4 (C field) in this time-dependent
background have also been studied.Comment: 15 pages, latex file, v2: typos corrected, ref added, v3: references
added, minor change
A systematic review and meta-analysis on delaying surgery for urothelial carcinoma of bladder and upper tract urothelial carcinoma: Implications for the COVID19 pandemic and beyond
© 2022 Leow, Tan, Tan, Tan, Chan, Tikkinen, Kamat, Sengupta, Meng, Shariat, Roupret, Decaestecker, Vasdev, Chong, Enikeev, Giannarini, Ficarra and Teoh. This is an openaccess article distributed under the terms of the Creative Commons Attribution License (CC BY). https://creativecommons.org/licenses/by/4.0/Purpose: The COVID-19 pandemic has led to competing strains on hospital resources and healthcare personnel. Patients with newly diagnosed invasive urothelial carcinomas of bladder (UCB) upper tract (UTUC) may experience delays to definitive radical cystectomy (RC) or radical nephro-ureterectomy (RNU) respectively. We evaluate the impact of delaying definitive surgery on survival outcomes for invasive UCB and UTUC. Methods: We searched for all studies investigating delayed urologic cancer surgery in Medline and Embase up to June 2020. A systematic review and meta-analysis was performed. Results: We identified a total of 30 studies with 32,591 patients. Across 13 studies (n = 12,201), a delay from diagnosis of bladder cancer/TURBT to RC was associated with poorer overall survival (HR 1.25, 95% CI: 1.09–1.45, p = 0.002). For patients who underwent neoadjuvant chemotherapy before RC, across the 5 studies (n = 4,316 patients), a delay between neoadjuvant chemotherapy and radical cystectomy was not found to be significantly associated with overall survival (pooled HR 1.37, 95% CI: 0.96–1.94, p = 0.08). For UTUC, 6 studies (n = 4,629) found that delay between diagnosis of UTUC to RNU was associated with poorer overall survival (pooled HR 1.55, 95% CI: 1.19–2.02, p = 0.001) and cancer-specific survival (pooled HR of 2.56, 95% CI: 1.50–4.37, p = 0.001). Limitations included between-study heterogeneity, particularly in the definitions of delay cut-off periods between diagnosis to surgery. Conclusions: A delay from diagnosis of UCB or UTUC to definitive RC or RNU was associated with poorer survival outcomes. This was not the case for patients who received neoadjuvant chemotherapy.Peer reviewe
En-Bloc Transurethral Resection of Non-Muscle-Invasive Bladder Cancer. Current Evidence and Glimpses into the Future
n/
Enhancing legacy in palliative care: study protocol for a randomized controlled trial of Dignity Therapy focused on positive outcomes
BACKGROUND: Dignity Therapy is a brief psychotherapy that can enhance a sense of legacy while addressing the emotional and existential needs of patients receiving hospice or palliative care. In Dignity Therapy, patients create a formalized “legacy” document that records their most cherished memories, their lessons learned in life, as well as their hopes and dreams for loved ones in the future. To date, this treatment has been studied for its impact on mitigating distress within hospice and palliative care populations and has provided mixed results. This study will instead focus on whether Dignity Therapy enhances positive outcomes in this population. METHODS/DESIGN: In this study, 90 patients with cancer receiving hospice or palliative care will complete a mixed-methods randomized controlled trial of Dignity Therapy (n = 45) versus Supportive Attention (n = 45). The patients will be enrolled in the study for 3 weeks, receiving a total of six study visits. The primary outcomes examine whether the treatment will quantitatively increase levels of positive affect and a sense of life closure. Secondary outcomes focus on gratitude, hope, life satisfaction, meaning in life, resilience, and self-efficacy. Using a fixed, embedded dataset design, this study will additionally use qualitative interviews to explore patients’ perceptions regarding the use of positive outcome measures and whether these outcomes are appropriately matched to their experiences in therapy. DISCUSSION: Dignity Therapy has shown mixed results when evaluating its impact on distress, although no other study to date has solely focused on the potential positive aspects of this treatment. This study is novel in its use of mixed methods assessments to focus on positive outcomes, and will provide valuable information about patients’ direct experiences in this area. TRIAL REGISTRATION: ISRCTN9138919
Loss of the Urothelial Differentiation Marker FOXA1 Is Associated with High Grade, Late Stage Bladder Cancer and Increased Tumor Proliferation
Approximately 50% of patients with muscle-invasive bladder cancer (MIBC) develop metastatic disease, which is almost invariably lethal. However, our understanding of pathways that drive aggressive behavior of MIBC is incomplete. Members of the FOXA subfamily of transcription factors are implicated in normal urogenital development and urologic malignancies. FOXA proteins are implicated in normal urothelial differentiation, but their role in bladder cancer is unknown. We examined FOXA expression in commonly used in vitro models of bladder cancer and in human bladder cancer specimens, and used a novel in vivo tissue recombination system to determine the functional significance of FOXA1 expression in bladder cancer. Logistic regression analysis showed decreased FOXA1 expression is associated with increasing tumor stage (p<0.001), and loss of FOXA1 is associated with high histologic grade (p<0.001). Also, we found that bladder urothelium that has undergone keratinizing squamous metaplasia, a precursor to the development of squamous cell carcinoma (SCC) exhibited loss of FOXA1 expression. Furthermore, 81% of cases of SCC of the bladder were negative for FOXA1 staining compared to only 40% of urothelial cell carcinomas. In addition, we showed that a subpopulation of FOXA1 negative urothelial tumor cells are highly proliferative. Knockdown of FOXA1 in RT4 bladder cancer cells resulted in increased expression of UPK1B, UPK2, UPK3A, and UPK3B, decreased E-cadherin expression and significantly increased cell proliferation, while overexpression of FOXA1 in T24 cells increased E-cadherin expression and significantly decreased cell growth and invasion. In vivo recombination of bladder cancer cells engineered to exhibit reduced FOXA1 expression with embryonic rat bladder mesenchyme and subsequent renal capsule engraftment resulted in enhanced tumor proliferation. These findings provide the first evidence linking loss of FOXA1 expression with histological subtypes of MIBC and urothelial cell proliferation, and suggest an important role for FOXA1 in the malignant phenotype of MIBC
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