306 research outputs found
On the Representation of General Interest Rate Models as Square Integrable Wiener Functionals
In the setting proposed by Hughston & Rafailidis (2005) we consider general
interest rate models in the case of a Brownian market information filtration
. Let be a square-integrable
-measurable random variable, and assume the non-degeneracy
condition that for all the random variable is not
-measurable. Let denote the integrand appearing in
the representation of as a stochastic integral, write for the
conditional variance of at time , and set .
Then is a potential, and as such can act as a model for a pricing
kernel (or state price density), where is the associated interest rate.
Under the stated assumptions, we prove the following: (a) that the money market
account process defined by is finite almost
surely at all finite times; and (b) that the product of the money-market
account and the pricing kernel is a local martingale, and is a martingale
provided a certain integrability condition is satisfied. The fact that a
martingale is thus obtained shows that from any non-degenerate element of
Wiener space satisfying the integrability condition we can construct an
associated interest-rate model. The model thereby constructed is valid over an
infinite time horizon, with strictly positive interest, and satisfies the
relevant intertemporal relations associated with the absence of arbitrage. The
results thus stated pave the way for the use of Wiener chaos methods in
interest rate modelling, since any such square-integrable Wiener functional
admits a chaos expansion, the individual terms of which can be regarded as
parametric degrees of freedom in the associated interest rate model to be fixed
by calibration to appropriately liquid sectors of the interest rate derivatives
markets.Comment: 17 page
Making for Change: Waltham Forest showcase
Making for Change: Waltham Forest is a partnership project developed by London College of Fashion, UAL (LCF) and Waltham Forest Council for London Borough of Culture 2019 and the Great Place scheme. The project uses fashion activism as a catalyst for positive change in the borough, aiming to ensure a lasting legacy within the community.
Led by Dr Francesco Mazzarella (Post-Doctoral Research Fellow at Centre for Sustainable Fashion, UAL), this exhibition comprises of three main areas – education, manufacturing and community – all of which examine the narrative of the artefacts, the makers and the stories.
The education theme showcases Making for Change: Waltham Forest’s contribution to embedding sustainability and future thinking in young people’s education. This section displays the teaching resources developed by LCF staff and a number of works produced by students from Waltham Forest schools.
Paying attention to issues of social, cultural, environmental and economic sustainability within the manufacturing industry, the second theme presents the research of three LCF staff members who have undertaken residencies across three (micro, medium and large) textile and fashion businesses – Cactus Leather, Blackhorse Lane Ateliers and Wagland Textiles.
The final area of the exhibition focuses on the local community, and those who participated in a number of making activities and creative workshops. On display are slogan t-shirt designs, upcycled garments from the art performance ‘I Wanna be me, I Wanna be (E)U’, and embroidery work, all of which showcase the creative skills gained by local people.
This exhibition is kindly funded by the Sheepdrove Trust. The Making for Change: Waltham Forest project is part-funded by London Borough of Culture 2019, Waltham Forest Council and Great Place: Creative Connections, a programme supported by Arts Council England and the National Lottery Heritage Fund. The Great Place Scheme is designed to put arts, culture and heritage at the heart of the local community.
‘Making for Change:
Waltham Forest’ Project Manager
Dr Francesco Mazzarella,
Centre for Sustainable Fashion, UAL
Curator
Fiona McKay,
Centre for Sustainable Fashion, UAL
Exhibition Coordinator
Mina Jugovic,
Centre for Sustainable Fashion, UAL
Graphic Design
LP Studio
Exhibition Design
Dean Slydell
Technical and AV Install:
Matt Carter
Photography
Andrew Mallinson
Francesco Mazzarella
Adam Razvi
Guillaume Valli
Nicole Zisman
Film
Short For
Learning Lines with Ordinal Constraints
We study the problem of finding a mapping f from a set of points into the real line, under ordinal triple constraints. An ordinal constraint for a triple of points (u,v,w) asserts that |f(u)-f(v)| < |f(u)-f(w)|. We present an approximation algorithm for the dense case of this problem. Given an instance that admits a solution that satisfies (1-?)-fraction of all constraints, our algorithm computes a solution that satisfies (1-O(?^{1/8}))-fraction of all constraints, in time O(n?) + (1/?)^{O(1/?^{1/8})} n
Intestinal Strongyle Genera in Different Typology of Donkey Farms in Tuscany, Central Italy
Intestinal strongyles are common helminths of donkeys, in which they may be responsible for disease and poor performance. This study aimed to identify intestinal strongyle genera in 55 naturally infected donkeys from three different farm typologies in Tuscany, central Italy, using morphological and metrical analysis of third stage larvae (L3) obtained from faecal cultures. Larvae were identified using two previous reported morphological identification keys. Moreover, eggs per gram (EPG) data were also evaluated to assess differences, if any, according to the farm typology, sex, and age of the examined donkeys. The results showed that small strongyles were prevalent in all donkey farms. In all examined farms, most (92-100%) of L3 were identified as cyathostomin species of the genera Cylicocyclus spp. and Cylicostephanus spp. Large strongyles of the genera Strongylus spp. and Triodontophorus spp., were identified at low percentage (8%), only in the single organic farm included in the study. A high agreement was observed between the two different morphometric keys used. No significant differences were found for EPG according to farm typology, and sex and age from the examined donkeys. This is the first report about genera identification of intestinal strongyles infecting donkeys in Tuscany, Italy
Mesenteric cystic lymphangioma mimicking an ileo-colic intussusception
Lymphangioma accounts for 5% of benign pediatric tumors and less than 1% is located in the abdomen. Indeed mesenteric cystic lymphangioma is a rare benign abdominal mass and its pathogenesis is still unknown.Mesenteric cystic lymphangioma is often diagnosed incidentally. Nevertheless, in some cases its clinical presentation can mimic several common surgical pathologies. Here we describe a case of mesenteric cystic lymphangioma mimicking an ileo-colic intussusception
Artificial Protein Coronas Enable Controlled Interaction with Corneal Epithelial Cells: New Opportunities for Ocular Drug Delivery
Topical administration is the most convenient route for ocular drug delivery, but only a minor fraction is retained in the precorneal pocket. To overcome this limitation, numerous drug delivery systems (DDS) have been developed. The protein corona (PC) is the layer of biomolecules (e.g., proteins, sugars, lipids, etc.) that forms around DDS in physiological environments by non-covalent interaction. The PC changes the DDS physical–chemical properties, providing them with a completely novel biological identity. The specific involvement of PC in ocular drug delivery has not been addressed so far. To fulfill this gap, here we explored the interaction between a library of four cationic liposome-DNA complexes (lipoplexes) and mucin (MUC), one of the main components of the tear film. We demonstrate that MUC binds to the lipoplex surface shifting both their size and surface charge and reducing their absorption by primary corneal epithelial cells. To surpass such restrictions, we coated lipoplexes with two different artificial PCs made of Fibronectin (FBN) and Val-Gly-Asp (VGA) tripeptide that are recognized by receptors expressed on the ocular surface. Both these functionalizations remarkedly boosted internalization in corneal epithelial cells with respect to pristine (i.e., uncoated) lipoplexes. This opens the gateway for the exploitation of artificial protein corona in targeted ocular delivery, which will significantly influence the development of novel nanomaterials
Pharmacological memory modulation to augment trauma-focused psychotherapy for PTSD: a systematic review of randomised controlled trials
Trauma-focused psychotherapy (tf-PT) is the first-line treatment for posttraumatic stress disorder (PTSD). Tf-PT focuses on processing and modulating trauma memories. Not all patients benefit, however, and there is room for improvement of efficacy. Pharmacologically augmenting trauma memory modulation in the context of tf-PT may help optimise treatment outcome. To systematically review effects of pharmacologically augmented memory modulation in the context of tf-PT for PTSD (PROSPERO preregistration ID: CRD42021230623). We conducted a systematic review of randomised controlled trials of psychotherapy treatment for PTSD. We included placebo-controlled studies that augmented at least one treatment session pharmacologically targeting memory extinction or reconsolidation. We calculated post-treatment between group (pharmacological augmentation vs placebo control) effect sizes of PTSD symptom severity. We included 13 RCTs. There was large heterogeneity in augmentation procedure and methodological quality. Four studies showed significantly greater PTSD symptom reduction in the pharmacological augmentation group (propranolol, hydrocortisone, dexamethasone, D-cycloserine) compared to placebo. Seven studies showed no significant effect of pharmacological augmentation compared to placebo (D-cycloserine, rapamycin, mifepristone, propranolol, mifepristone combined with D-cycloserine, methylene blue). Two studies showed significantly smaller PTSD symptom reduction in the pharmacological augmentation group (D-cycloserine, dexamethasone) compared to placebo. Results of pharmacological augmentation were mixed overall and heterogenous for the pharmacological agents tested in more than one study. Additional studies and replications are needed to identify which pharmacological agents work, in which combination and to identify patient groups that benefit most to tailor PTSD treatment
Donor Cell Acute Myeloid Leukemia after Hematopoietic Stem Cell Transplantation for Chronic Granulomatous Disease: A Case Report and Literature Review
The patient reported here underwent hematopoietic stem cell transplantation (HSCT) due to chronic granulomatous disease (CGD) caused by biallelic mutations of the NCF1 gene. Two years later, he developed AML, which was unexpected and was recognized via sex-mismatched chromosomes as deriving from the donor cells; the patient was male, and the donor was his sister. Donor cell leukemia (DCL) is very rare, and it had never been reported in patients with CGD after HSCT. In the subsequent ten years, the AML relapsed three times and the patient underwent chemotherapy and three further HSCTs; donors were the same sister from the first HSCT, an unrelated donor, and his mother. The patient died during the third relapse. The DCL was characterized since onset by an acquired translocation between chromosomes 9 and 11, with a molecular rearrangement between the MLL and MLLT3 genes-a quite frequent cause of AML. In all of the relapses, the malignant clone had XX sex chromosomes and this rearrangement, thus indicating that it was always the original clone derived from the transplanted sister's cells. It exhibited the ability to remain quiescent in the BM during repeated chemotherapy courses, remission periods and HSCT. The leukemic clone then acquired different additional anomalies during the ten years of follow-up, with cytogenetic results characterized both by anomalies frequent in AML and by different, non-recurrent changes. This type of cytogenetic course is uncommon in AML
Matrix Model as a Mirror of Chern-Simons Theory
Using mirror symmetry, we show that Chern-Simons theory on certain manifolds
such as lens spaces reduces to a novel class of Hermitian matrix models, where
the measure is that of unitary matrix models. We show that this agrees with the
more conventional canonical quantization of Chern-Simons theory. Moreover,
large N dualities in this context lead to computation of all genus A-model
topological amplitudes on toric Calabi-Yau manifolds in terms of matrix
integrals. In the context of type IIA superstring compactifications on these
Calabi-Yau manifolds with wrapped D6 branes (which are dual to M-theory on G2
manifolds) this leads to engineering and solving F-terms for N=1 supersymmetric
gauge theories with superpotentials involving certain multi-trace operators.Comment: harvmac, 54 pages, 13 figure
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