Transition effects from laparocscopic to robotic surgery skills in small cavities.

Conventional laparoscopic surgery (LS) is being challenged by the ever-increasing use of robotic surgery (RS) to perform reconstructive procedures. The purpose of this study was to assess the acquisition of skills in both techniques and the potential transfer of skills from one technique to the other when restricted spaces are involved. A preclinical randomized crossover study design was implemented. Twelve subjects performed two different reproducible drill procedures: "Thread the Ring" (TR) and "Transfer the Plot" (TP). To assess surgical proficiency in confined workspaces, these exercises were performed with LS and RS technology in a pediatric laparoscopic surgery (PLS) simulator. Each performance was recorded and evaluated by two reviewers using objective structured assessment of technical skills (OSATS). The times to complete the TP and the TR procedure were significantly shorter with RS compared to LS (64 s vs. 319 s; p < 0.0001 for both TP and TR). A significant transfer effect of skills between LS and RS was noted for the TP exercise (p = 0.006). The percentage improvement was greater overall with LS, meaning a higher number of trials were required to adequately master the procedure. This study demonstrated that RS performed significantly better compared to LS on pediatric simulation devices. A transfer effect was identified from LS to RS exclusively. The learning curves showed that progression was definitely longer with LS. These results, indicate that novice surgeons should be encouraged to persist with learning LS, and they support the use of a pediatric robotic simulation device.

Megapixel multi-elemental imaging by Laser-Induced Breakdown Spectroscopy, a technology with considerable potential for paleoclimate studies.

Paleoclimate studies play a crucial role in understanding past and future climates and their environmental impacts. Current methodologies for performing highly sensitive elemental analysis at micrometre spatial resolutions are restricted to the use of complex and/or not easily applied techniques, such as synchrotron radiation X-ray fluorescence micro-analysis (µ-SRXRF), nano secondary ion mass spectrometry (nano-SIMS) or laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Moreover, the analysis of large samples (>few cm²) with any of these methods remains very challenging due to their relatively low acquisition speed (~1-10 Hz), and because they must be operated in vacuum or controlled atmosphere. In this work, we proposed an imaging methodology based on laser-induced breakdown spectroscopy, to perform fast multi-elemental scanning of large geological samples with high performance in terms of sensitivity (ppm-level), lateral resolution (up to 10 µm) and operating speed (100 Hz). This method was successfully applied to obtain the first megapixel images of large geological samples and yielded new information, not accessible using other techniques. These results open a new perspective into the use of laser spectroscopy in a variety of geochemical applications.

Qualitative and quantitative analysis of milk for the detection of adulteration by Laser Induced Breakdown Spectroscopy (LIBS).

The present work focuses on the development of a fast and cost effective method based on Laser Induced Breakdown Spectroscopy (LIBS) to the quality control, traceability and detection of adulteration in milk. Two adulteration cases have been studied; a qualitative analysis for the discrimination between different milk blends and quantification of melamine in adulterated toddler milk powder. Principal Component Analysis (PCA) and neural networks (NN) have been used to analyze LIBS spectra obtaining a correct classification rate of 98% with a 100% of robustness. For the quantification of melamine, two methodologies have been developed; univariate analysis using CN emission band and multivariate calibration NN model obtaining correlation coefficient (R2) values of 0.982 and 0.999 respectively. The results of the use of LIBS technique coupled with chemometric analysis are discussed in terms of its potential use in the food industry to perform the quality control of this dairy product.

Identification and Discrimination of Brands of Fuels by Gas Chromatography and Neural Networks Algorithm in Forensic Research.

The detection of adulteration of fuels and its use in criminal scenes like arson has a high interest in forensic investigations. In this work, a method based on gas chromatography (GC) and neural networks (NN) has been developed and applied to the identification and discrimination of brands of fuels such as gasoline and diesel without the necessity to determine the composition of the samples. The study included five main brands of fuels from Spain, collected from fifteen different local petrol stations. The methodology allowed the identification of the gasoline and diesel brands with a high accuracy close to 100%, without any false positives or false negatives. A success rate of three blind samples was obtained as 73.3%, 80%, and 100%, respectively. The results obtained demonstrate the potential of this methodology to help in resolving criminal situations.

Classification of red wine based on its protected designation of origin (PDO) using Laser-induced Breakdown Spectroscopy (LIBS).

This work reports on a simple and fast classification procedure for the quality control of red wines with protected designation of origin (PDO) by means of Laser Induced Breakdown Spectroscopy (LIBS) technique combined with Neural Networks (NN) in order to increase the quality assurance and authenticity issues. A total of thirty-eight red wine samples from different PDO were analyzed to detect fake wines and to avoid unfair competition in the market. LIBS is well known for not requiring sample preparation, however, in order to increase its analytical performance a new sample preparation treatment by previous liquid-to-solid transformation of the wine using a dry collagen gel has been developed. The use of collagen pellets allowed achieving successful classification results, avoiding the limitations and difficulties of working with aqueous samples. The performance of the NN model was assessed by three validation procedures taking into account their sensitivity (internal validation), generalization ability and robustness (independent external validation). The results of the use of a spectroscopic technique coupled with a chemometric analysis (LIBS-NN) are discussed in terms of its potential use in the food industry, providing a methodology able to perform the quality control of alcoholic beverages.

Rapid identification and discrimination of bacterial strains by laser induced breakdown spectroscopy and neural networks.

Identification and discrimination of bacterial strains of same species exhibiting resistance to antibiotics using laser induced breakdown spectroscopy (LIBS) and neural networks (NN) algorithm is reported. The method has been applied to identify 40 bacterial strains causing hospital acquired infections (HAI), i.e. Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Salmonella typhimurium, Salmonella pullurum and Salmonella salamae. The strains analyzed included both isolated from clinical samples and constructed in laboratory that differ in mutations as a result of their resistance to one or more antibiotics. Small changes in the atomic composition of the bacterial strains, as a result of their mutations and genetic variations, were detected by the LIBS-NN methodology and led to their identification and classification. This is of utmost importance because solely identification of bacterial species is not sufficient for disease diagnosis and identification of the actual strain is also required. The proposed method was successfully able to discriminate strains of the same bacterial species. The optimized NN models provided reliable bacterial strain identification with an index of spectral correlation higher than 95% for the samples analyzed, showing the potential and effectiveness of the method to address the safety and social-cost HAI-related issue.

Biomechanics of pivoting appliances.

The effects of fulcrum-type splints on the temporomandibular joints are unclear. An analysis of bilateral temporomandibular joint linear tomograms of 20 volunteers was made. This study was carried out to evaluate and quantify the condylar distraction caused by the use of interocclusal splints with pivots located simultaneously on second molars. Statistical results showed an average condylar lowering of 1.3 mm in 87.5% of the subjects (P < .05) while clenching with lips closed and wearing this splint. A real bilateral condylar distraction was shown in 30% of the subjects, 35% showed both condyles in a protruded position, and 35% of the subjects showed a combined situation.

Terapia con gamaglobulina

El esfuerzo de un nn número cada vez mayor de científicos que trabajan en el campo de la inmunología, les ha permitido entregar a la práctica clínica, dos generaciones de inmunoglobulina parenteral: la normal y la específica, ambas de aplicación intramuscular (IM) y la ultima, la gamaglobulina de uso intravenoso (IV). Este trabajo pretende dos objetivos, el uno, es hacer una revisión actualizada de sus usos, pasando por un breve camino de la evaluación investigativa de la inmunología, hasta llegar a la obtención y actual aplicación de la segunda generación de la inmunoglobulina, la de uso intravenoso. El segundo objetivo, es introducirnos en el tema como anticipo a un estudio de la aplicabilidad de esta terapia en Servicios como el de Neonatología del Hospital de Niños "Baca Ortiz"