426 research outputs found
Transcriptomic analysis of the response of Acropora millepora to hypo-osmotic stress provides insights into DMSP biosynthesis by corals
© 2017 The Author(s). Background: Dimethylsulfoniopropionate (DMSP) is a small sulphur compound which is produced in prodigious amounts in the oceans and plays a pivotal role in the marine sulfur cycle. Until recently, DMSP was believed to be synthesized exclusively by photosynthetic organisms; however we now know that corals and specific bacteria can also produce this compound. Corals are major sources of DMSP, but the molecular basis for its biosynthesis is unknown in these organisms. Results: Here we used salinity stress, which is known to trigger DMSP production in other organisms, in conjunction with transcriptomics to identify coral genes likely to be involved in DMSP biosynthesis. We focused specifically on both adults and juveniles of the coral Acropora millepora: after 24 h of exposure to hyposaline conditions, DMSP concentrations increased significantly by 2.6 fold in adult corals and 1.2 fold in juveniles. Concomitantly, candidate genes enabling each of the necessary steps leading to DMSP production were up-regulated. Conclusions: The data presented strongly suggest that corals use an algal-like pathway to generate DMSP from methionine, and are able to rapidly change expression of the corresponding genes in response to environmental stress. However, our data also indicate that DMSP is unlikely to function primarily as an osmolyte in corals, instead potentially serving as a scavenger of ROS and as a molecular sink for excess methionine produced as a consequence of proteolysis and osmolyte catabolism in corals under hypo-osmotic conditions
Pricing Exotic Options in a Path Integral Approach
In the framework of Black-Scholes-Merton model of financial derivatives, a
path integral approach to option pricing is presented. A general formula to
price European path dependent options on multidimensional assets is obtained
and implemented by means of various flexible and efficient algorithms. As an
example, we detail the cases of Asian, barrier knock out, reverse cliquet and
basket call options, evaluating prices and Greeks. The numerical results are
compared with those obtained with other procedures used in quantitative finance
and found to be in good agreement. In particular, when pricing at-the-money and
out-of-the-money options, the path integral approach exhibits competitive
performances.Comment: 21 pages, LaTeX, 3 figures, 6 table
Use of the infra hyoid musculo-cutaneous flap in soft palate reconstruction.
To review a series of 23 consecutive patients with squamous cell carcinomas arising from oropharynx who underwent infra hyoid musculo-cutaneous flap reconstruction including soft palate in alternative to free radial forearm flap or maxillofacial prosthesis. Post operative radiotherapy was performed for all patients.Every reconstruction healed quickly without major wound complications. The functional results evaluated by speech and swallowing capacities, were good for 17 patients, fair for 4 patients and bad for 2.The infra hyoid musculo-cutaneous flap is a versatile, reliable and convenient flap suitable for repairing small and medium sized defects; it can be used in combination with other flaps, and in selected cases obviates the need for a microvascular free radial forearm flap or maxillofacial prosthesis
Finite one dimensional impenetrable Bose systems: Occupation numbers
Bosons in the form of ultra cold alkali atoms can be confined to a one
dimensional (1d) domain by the use of harmonic traps. This motivates the study
of the ground state occupations of effective single particle states
, in the theoretical 1d impenetrable Bose gas. Both the system on a
circle and the harmonically trapped system are considered. The and
are the eigenvalues and eigenfunctions respectively of the one body
density matrix. We present a detailed numerical and analytic study of this
problem. Our main results are the explicit scaled forms of the density
matrices, from which it is deduced that for fixed the occupations
are asymptotically proportional to in both the circular
and harmonically trapped cases.Comment: 22 pages, 8 figures (.eps), uses REVTeX
A buccal mucosa carcinoma treated with high dose rate brachytherapy
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135251/1/acm20008.pd
Quadratic optimal functional quantization of stochastic processes and numerical applications
In this paper, we present an overview of the recent developments of
functional quantization of stochastic processes, with an emphasis on the
quadratic case. Functional quantization is a way to approximate a process,
viewed as a Hilbert-valued random variable, using a nearest neighbour
projection on a finite codebook. A special emphasis is made on the
computational aspects and the numerical applications, in particular the pricing
of some path-dependent European options.Comment: 41 page
Emapalumab in children with primary hemophagocytic lymphohistiocytosis
Primary hemophagocytic lymphohistiocytosis is a rare syndrome characterized by immune dysregulation and hyperinflammation. It typically manifests in infancy and is associated with high mortality. METHODS We investigated the efficacy and safety of emapalumab (a human anti-interferon-γ antibody), administered with dexamethasone, in an open-label, single-group, phase 2-3 study involving patients who had received conventional therapy before enrollment (previously treated patients) and previously untreated patients who were 18 years of age or younger and had primary hemophagocytic lymphohistiocytosis. The patients could enter a long-term follow-up study until 1 year after allogeneic hematopoietic stem-cell transplantation or until 1 year after the last dose of emapalumab, if transplantation was not performed. The planned 8-week treatment period could be shortened or extended if needed according to the timing of transplantation. The primary efficacy end point was the overall response, which was assessed in the previously treated patients according to objective clinical and laboratory criteria. RESULTS At the cutoff date of July 20, 2017, a total of 34 patients (27 previously treated patients and 7 previously untreated patients) had received emapalumab; 26 patients completed the study. A total of 63% of the previously treated patients and 65% of the patients who received an emapalumab infusion had a response; these percentages were significantly higher than the prespecified null hypothesis of 40% (P=0.02 and P=0.005, respectively). In the previously treated group, 70% of the patients were able to proceed to transplantation, as were 65% of the patients who received emapalumab. At the last observation, 74% of the previously treated patients and 71% of the patients who received emapalumab were alive. Emapalumab was not associated with any organ toxicity. Severe infections developed in 10 patients during emapalumab treatment. Emapalumab was discontinued in 1 patient because of disseminated histoplasmosis. CONCLUSIONS Emapalumab was an efficacious targeted therapy for patients with primary hemophagocytic lymphohistiocytosis
Emapalumab in children with primary hemophagocytic lymphohistiocytosis
Primary hemophagocytic lymphohistiocytosis is a rare syndrome characterized by immune dysregulation and hyperinflammation. It typically manifests in infancy and is associated with high mortality
Effects of Black Leaf Streak Disease and Sigatoka Disease on fruit quality and maturation process of bananas produced in the subtropical conditions of southern Brazil
Banana fruits are harvested at the green-mature stage (pre-climacteric) in order to allow sufficient time for transport and marketing. The time between the harvest and the initiation of the natural ripening process is called green life (GL), which is closely correlated to physiological age. Sigatoka Disease (SD: also called yellow Sigatoka) and Black Leaf Streak Disease (BLSD; also called black Sigatoka) are the main foliar diseases affecting banana production. The aim of this work was to investigate the influence of these diseases on banana GL and postharvest behavior in subtropical conditions (southeastern Brazil). The results showed that both diseases shortened the banana's GL when compared to control bananas of the same physiological age. Moreover, fruits from infested plots showed higher values of CO2 (+100% for SD and +300% for BLSD) and C2H4 production (+30% for SD and +60% for BLSD) at the climacteric peak. BLSD caused 40% reduction in fruit weight. Fruits from plants with a high degree of SD or BLSD undergo an altered maturation process. (C) 2011 Elsevier Ltd. All rights reserved.MA
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