Search results for "bioengineering"
showing 10 items of 1963 documents
Energy calibration of the NEXT-White detector with 1% resolution near Q ββ of 136Xe
2019
Excellent energy resolution is one of the primary advantages of electroluminescent high pressure xenon TPCs, and searches for rare physics events such as neutrinoless double-beta decay ($\beta\beta0\nu$) require precise energy measurements. Using the NEXT-White detector, developed by the NEXT (Neutrino Experiment with a Xenon TPC) collaboration, we show for the first time that an energy resolution of 1% FWHM can be achieved at 2.6 MeV, establishing the present technology as the one with the best energy resolution of all xenon detectors for $\beta\beta0\nu$ searches.
Characterization of softwood and hardwood lignoboost kraft lignins with emphasis on their antioxidant activity
2014
Fractionation of softwood and hardwood LignoBoost kraft lignins, using sequential extraction with organic solvents of increasing hydrogen-bonding ability (dichloromethane, n-propanol, and methanol), was carried out. Using SEC, analytical pyrolysis, FTIR and UV/VIS spectroscopy, and chemical analytical methods, four fractions were obtained and characterized in terms of their yield, composition, functionality, lignin structural features, and antioxidant properties. In tests with free radicals (ABTS●+, DPPH●, O2●-) and the ORAC (oxygen radical absorbance capacity) assay, the high radical scavenging capacity of the lignin’s soluble fractions was demonstrated. The antioxidant activity of the fra…
Real-time control strategy for nitrogen removal via nitrite in a SHARON reactor using pH and ORP sensors
2012
This paper presents a real-time control strategy for nitrogen removal via nitrite in a continuous flow SHARON reactor using on-line available and industrially feasible sensors (pH and ORP). The developed control strategy optimizes the length of aerobic and anoxic phases as well as the external carbon source addition. This strategy, implemented in a laboratory-scale SHARON reactor fed with synthetic wastewater and real dewatering sludge supernatant, was able to cope with step variations in influent flow rate and ammonium concentration. The main advantages of this control strategy over the traditional operation mode with fixed carbon source dosification and fixed length cycle operation were: …
Modeling the decay of nitrite oxidizing bacteria under different reduction potential conditions
2018
[EN] Autotrophic growth and decay rates of ammonium and nitrite oxidizing bacteria (AOB and NOB, respectively) have a significant impact on the design and on the process performance of wastewater treatment systems where nitrification occurs. Literature data on the separate decay rates of AOB and NOB is scarce and inconsistent. In this study, batch experiments based on respirometric techniques were conducted to determine the NOB decay rates under different oxidation-reduction potential conditions, in order to widen the understanding of nitrite dynamics. The decay rate measured under anoxic conditions was 85% lower than under aerobic conditions, whereas under anaerobic conditions the decay ra…
Optimization of a decellularized protocol of porcine tracheas. Long-term effects of cryopreservation. A histological study
2021
[EN] Objective: The aim of this study was to optimize a decellularization protocol in the trachea of Sus scrofa domestica (pig) as well as to study the effects of long-term cryopreservation on the extracellular matrix of decellularized tracheas. Methods: Porcine tracheas were decellularized using Triton X-100, SDC, and SDS alone or in combination. The effect of these detergents on the extracellular matrix characteristics of decellularized porcine tracheas was evaluated at the histological, biomechanical, and biocompatibility level. Morphometric approaches were used to estimate the effect of detergents on the collagen and elastic fibers content as well as on the removal of chondrocytes from …
Role of Positron Emission Tomography for the Monitoring of Response to Therapy in Breast Cancer
2015
Abstract This review considers the potential utility of positron emission tomography (PET) tracers in the setting of response monitoring in breast cancer, with a special emphasis on glucose metabolic changes assessed with 18F-fluorodeoxyglucose (FDG). In the neoadjuvant setting of breast cancer, the metabolic response can predict the final complete pathologic response after the first cycles of chemotherapy. Because tumor metabolic behavior highly depends on cancer subtype, studies are ongoing to define the optimal metabolic criteria of tumor response in each subtype. The recent multicentric randomized AVATAXHER trial has suggested, in the human epidermal growth factor 2-positive subtype, a …
Positron emission tomography and neoadjuvant therapy of breast cancer
2011
The increasing use of neoadjuvant therapy for breast cancer has led to the development of early surrogate markers of response. Positron emission tomography (PET) allows noninvasive study of fundamental biologic processes in the tumor; furthermore, PET provides various markers to assess tumor response early in the course of therapy. Numerous studies have shown that changes in tumor glucose metabolism during therapy are significantly correlated with final response and patient outcome. Moreover, new PET tracers that are currently being developed or under evaluation, providing specific information on tumor characteristics or receptor expression, will assist the development of new targeted antic…
Absolute volume of the rectum and AUC from rectal DVH between 25Gy and 50Gy predict acute gastrointestinal toxicity with IG-IMRT in prostate cancer
2016
International audience; Background: To determine whether dose/volume specific endpoints (DVSE) or Area under the rectal DVH curve (rAUC) better predict acute gastrointestinal (GI) toxicity in prostate cancer patients treated with IMRT in the era of daily image guidance (IG-IMRT). Methods: A set of DVSE was recorded from V25 to V75 (increments of 5Gy) (both in % and in cc) for 180 men. The rAUC was calculated for doses ranging between 25Gy and 50Gy (rAUC(25-50)). Univariate and multivariate logistic regressions were performed to determine the relationship between DVSE or rAUC(25-50) and the appearance of any acute GI toxicity. Results: The rates of acute grade 1 (G1), G2 and G3 GI toxicities…
18F-FDG PET-Derived Tumor Blood Flow Changes After 1 Cycle of Neoadjuvant Chemotherapy Predicts Outcome in Triple-Negative Breast Cancer
2016
International audience; Previous studies have suggested that early changes in blood flow (BF) in response to neoadjuvant chemotherapy and evaluated with 150-water are a surrogate biomarker of outcome in women with breast cancer. This study investigates, in the triple-negative breast cancer subtype, the prognostic relevance of tumor BF changes (Delta BF) in response to chemotherapy, assessed using a short dynamic F-18-FDG PET acquisition. Methods: Forty-six consecutive women with triple-negative breast cancer and an indication for neoadjuvant chemotherapy were prospectively included. Women benefited from a baseline F-18-FDG PET examination with a 2-min chest-centered dynamic acquisition, sta…
Association de radiothérapie externe et de curiethérapie pour les cancers de la prostate
2017
International audience; Brachytherapy as sole treatment is standard of care for D’Amico classification low-risk prostate cancer. For intermediate and high-risk patients, brachytherapy can be associated to external beam radiation therapy to better take into account the risk of extracapsular effraction and/or seminal vesicle involvement. Three randomized studies have shown that this association increases freedom from relapse survival compared to exclusive external beam radiation therapy. This benefit is not shown for overall survival. The addition of a hormonal therapy to this association is most likely mandatory for high-risk patients, and needs to be confirmed for intermediate risk patients…