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1.
Cureus ; 16(2): e53701, 2024 Feb.
Article En | MEDLINE | ID: mdl-38455812

Ankyloglossia can be related to a number of complications, such as breastfeeding difficulties or alterations in craniofacial development. Treatment can involve surgery to correct the altered lingual frenulum and can be performed by various techniques. The purpose of this paper is to present two case reports of ankyloglossia in pediatric patients of different ages, the diagnostic criteria, and the treatment decision rationale, which led to a lingual frenotomy performed with a diode laser.

2.
Biology (Basel) ; 12(7)2023 Jun 29.
Article En | MEDLINE | ID: mdl-37508366

Microalgae are a promising feedstock for bioethanol production, essentially due to their high growth rates and absence of lignin. Hydrolysis-where the monosaccharides are released for further fermentation-is considered a critical step, and its optimization is advised for each raw material. The present study focuses on the thermal acid hydrolysis (with sulfuric acid) of Aurantiochytrium sp. through a response surface methodology (RSM), studying the effect of acid concentration, hydrolysis time and biomass/acid ratio on both sugar concentration of the hydrolysate and biomass conversion yield. Preliminary studies allowed to establish the range of the variables to be optimized. The obtained models predicted a maximum sugar concentration (18.05 g/L; R2 = 0.990) after 90 min of hydrolysis, using 15% (w/v) biomass/acid ratio and sulfuric acid at 3.5% (v/v), whereas the maximum conversion yield (12.86 g/100 g; R2 = 0.876) was obtained using 9.3% (w/v) biomass/acid ratio, maintaining the other parameters. Model outputs indicate that the biomass/acid ratio and time are the most influential parameters on the sugar concentration and yield models, respectively. The study allowed to obtain a predictive model that is very well adjusted to the experimental data to find the best saccharification conditions for the Aurantiochytrium sp. microalgae.

3.
Phys Med Biol ; 67(13)2022 06 27.
Article En | MEDLINE | ID: mdl-35561700

Presumably, intensity-modulated proton radiotherapy (IMPT) is the most powerful form of proton radiotherapy. In the current state of the art, IMPT beam configurations (i.e. the number of beams and their directions) are, in general, chosen subjectively based on prior experience and practicality. Beam configuration optimization (BCO) for IMPT could, in theory, significantly enhance IMPT's therapeutic potential. However, BCO is complex and highly computer resource-intensive. Some algorithms for BCO have been developed for intensity-modulated photon therapy (IMRT). They are rarely used clinically mainly because the large number of beams typically employed in IMRT renders BCO essentially unnecessary. Moreover, in the newer form of IMRT, volumetric modulated arc therapy, there are no individual static beams. BCO is of greater importance for IMPT because it typically employs a very small number of beams (2-4) and, when the number of beams is small, BCO is critical for improving plan quality. However, the unique properties and requirements of protons, particularly in IMPT, make BCO challenging. Protons are more sensitive than photons to anatomic changes, exhibit variable relative biological effectiveness along their paths, and, as recently discovered, may spare the immune system. Such factors must be considered in IMPT BCO, though doing so would make BCO more resource intensive and make it more challenging to extend BCO algorithms developed for IMRT to IMPT. A limited amount of research in IMPT BCO has been conducted; however, considerable additional work is needed for its further development to make it truly effective and computationally practical. This article aims to provide a review of existing BCO algorithms, most of which were developed for IMRT, and addresses important requirements specific to BCO for IMPT optimization that necessitate the modification of existing approaches or the development of new effective and efficient ones.


Proton Therapy , Radiotherapy, Intensity-Modulated , Photons/therapeutic use , Protons , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted
4.
Clin Nephrol ; 89(2): 120-122, 2018 Feb.
Article En | MEDLINE | ID: mdl-29231161

Peritoneopleural shunt is an uncommon complication of peritoneal dialysis (PD) usually presenting early as a right pleural transudate. Peritoneopericardial shunt is an even rarer entity in PD, almost never occurring spontaneously. We present the case of a 37-year-old woman on PD for 24 months exhibiting a left pleural and pericardial effusion following pneumonia. Pleural fluid was initially compatible with an exudate with a high glucose concentration and later with a transudate. In order to clarify the suspicion of an ongoing shunt an abdominal scintigraphy was performed confirming the diagnosis of a peritoneopleuropericardial communication. This case underlines the importance of considering this unusual diagnosis in a patient on long-term PD. Its timely diagnosis is important to stop PD and start hemodialysis.
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Pericardial Effusion/diagnosis , Pericardial Effusion/etiology , Peritoneal Dialysis/adverse effects , Pleural Effusion/diagnosis , Pleural Effusion/etiology , Renal Insufficiency, Chronic/therapy , Adult , Female , Humans
5.
Phys Med Biol ; 58(9): 2939-53, 2013 May 07.
Article En | MEDLINE | ID: mdl-23574810

Generally, the inverse planning of radiation therapy consists mainly of the fluence optimization. The beam angle optimization (BAO) in intensity-modulated radiation therapy (IMRT) consists of selecting appropriate radiation incidence directions and may influence the quality of the IMRT plans, both to enhance better organ sparing and to improve tumor coverage. However, in clinical practice, most of the time, beam directions continue to be manually selected by the treatment planner without objective and rigorous criteria. The goal of this paper is to introduce a novel approach that uses beam's-eye-view dose ray tracing metrics within a pattern search method framework in the optimization of the highly non-convex BAO problem. Pattern search methods are derivative-free optimization methods that require a few function evaluations to progress and converge and have the ability to better avoid local entrapment. The pattern search method framework is composed of a search step and a poll step at each iteration. The poll step performs a local search in a mesh neighborhood and ensures the convergence to a local minimizer or stationary point. The search step provides the flexibility for a global search since it allows searches away from the neighborhood of the current iterate. Beam's-eye-view dose metrics assign a score to each radiation beam direction and can be used within the pattern search framework furnishing a priori knowledge of the problem so that directions with larger dosimetric scores are tested first. A set of clinical cases of head-and-neck tumors treated at the Portuguese Institute of Oncology of Coimbra is used to discuss the potential of this approach in the optimization of the BAO problem.


Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Intensity-Modulated/methods , Head and Neck Neoplasms/radiotherapy , Humans
6.
Bioresour Technol ; 100(24): 6355-61, 2009 Dec.
Article En | MEDLINE | ID: mdl-19664916

The objective of the present work was: (i) to enable biodiesel production from acid waste lard; (ii) to study the esterification reaction as possible pre-treatment at different temperatures, catalyst amount and reaction times; (iii) to evaluate biodiesel quality according to EN 14214 after basic transesterification of the pre-treated fat; and (iv) to predict the impact of using such waste as raw material in mixture with soybean oil. Temperature and catalyst amount were the most important reaction conditions which mostly affected biodiesel quality, namely viscosity and purity. The selected pre-treatment conditions were 65 degrees C, 2.0 wt% H(2)SO(4) and 5 h, which allowed obtaining a product with a viscosity of 4.81 mm(2) s(-1) and a purity of 99.6 wt%. The proposed pre-treatment was effective to enable acid wastes as single raw materials for biodiesel production with acceptable quality; however, low yields were obtained (65 wt%). Alkali transesterification of a mixture of waste lard and soybean oil resulted in a product with a purity of 99.8 wt% and a yield of 77.8 wt%, showing that blending might be an interesting alternative to recycle such wastes. Also, because in addition to using conventional and relatively economical processes, some biodiesel properties depending on the raw material composition (such as the iodine value) might even be improved.


Bioelectric Energy Sources , Dietary Fats/analysis , Waste Products/analysis , Acids , Catalysis , Chromatography, Gas , Esterification , Esters/analysis , Soybean Oil/chemistry , Temperature , Viscosity
7.
J Environ Manage ; 85(4): 833-46, 2007 Dec.
Article En | MEDLINE | ID: mdl-17884280

Commercial activated carbon is a preferred adsorbent for the removal of micropollutants from the aqueous phase; however, its widespread use is restricted due to high associated costs. To decrease treatment costs, attempts have been made to find inexpensive alternative activated carbon (AC) precursors, such as waste materials. Some reviews report the use of waste materials for the preparation of AC; however, these studies are restricted to either type of wastes, preparation procedures, or specific aqueous-phase applications. The present work reviews and evaluates literature dedicated both to the preparation of AC by recycling different types of waste materials and also to its application in various aqueous-phase treatments. It is clear that conventional (from agriculture and wood industry) and non-conventional (from municipal and industrial activities) wastes can be used to prepare AC, that can be applied in various aqueous treatment processes, namely to remove organic pollutants, dyes, volatile organic compounds, and heavy metals. Moreover, high surface areas can be obtained using either physical or chemical activation; however, combined treatments might enhance the surface properties of the adsorbent, therefore increasing its adsorption capacity. It is evident from the revision made that AC prepared from both conventional and non-conventional wastes might effectively compete with the commercial ones. This happens mostly when the activation procedures are optimized considering both the raw material used to produce the carbons and the contaminants to be removed.


Charcoal/chemistry , Waste Products , Metals, Heavy/chemistry , Waste Disposal, Fluid/methods , Waste Management/methods
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