Nosological Diagnosis, Theories of Categorization, and Argumentations by Analogy.

The nosological diagnosis is a particular type of nontheoretical diagnosis consisting of identifying the disease that afflicts the patient without explaining the underlying etiopathological mechanisms. Its origins are within the essentialist point of view on the nature of diseases, which dates back at least to 18th-century taxonomy studies. In this article, we propose a model of nosological diagnosis as a two-phase process composed of the categorization of inductive inferences and argumentations by analogy. In the inductive phase, disease entities are identified by means of typicality-based categorization processes, and meaningful clinical samples are learned (abstract clinical cases, i.e., syndromes and actual cases); in the subsequent phase, those samples are used as the bases of argumentations by analogy to obtain a diagnosis for a given patient. This model extends the prototype resemblance theory of disease including also the exemplar theory proposed in cognitive science and, moreover, it frames the clinical activity of nosological diagnosis and how it can be explained within the theory of argumentation. According to it, diagnosis based on the recognition of a typical syndrome is explained in terms of the prototype theory of categorization and the antisymmetrical argumentation by analogy, while diagnosis based on a comparison with a previous clinical case is explained by the exemplar theory of categorization and by the symmetrical argumentation by analogy.

Application of Near Infrared Spectroscopy for the Rapid Assessment of Nutritional Quality of Different Strawberry Cultivars.

Strawberry is the most cultivated berry fruit globally and it is really appreciated by consumers because of its characteristics, mainly bioactive compounds with antioxidant properties. During the breeding process, it is important to assess the quality characteristics of the fruits for a better selection of the material, but the conventional approaches involve long and destructive lab techniques. Near infrared spectroscopy (NIR) could be considered a valid alternative for speeding up the breeding process and is not destructive. In this study, a total of 216 strawberry fruits belonging to four different cultivars have been collected and analyzed with conventional lab analysis and NIR spectroscopy. In detail, soluble solid content, acidity, vitamin C, anthocyanin, and phenolic acid have been determined. Partial least squares discriminant analysis (PLS-DA) models have been developed to classify strawberry fruits belonging to the four genotypes according to their quality and nutritional properties. NIR spectroscopy could be considered a valid non-destructive phenotyping method for monitoring the nutritional parameters of the fruit and ensuring the fruit quality, speeding up the breeding program.

Nerve-sparing class III-IV radical hysterectomy: urodynamic study and surgical technique.

OBJECTIVE: The aim of this study was to demonstrate the impact of the nerve-sparing radical hysterectomy on the bladder function. METHODS: Patients with cervical cancer stage 1B1 to IIB, who underwent type 3 to 4 nerve-sparing radical hysterectomy, were evaluated with urodynamic test before and within 6 months from surgery. Stage IB2 to IIB patients were treated with platinum-based neoadjuvant chemotherapy. Bladder catheter was removed in postoperative day 4, and patients were educated to clean intermittent self-catheterization. Urinary symptoms were evaluated with a questionnaire administered before and 3, 6, and 12 months after surgery. Patients treated with adjuvant chemoradiotherapy were excluded from the study. RESULTS: Fifteen patients (stage IB1, 7; IB2, 3; and IIB, 5) completed the study. Eight (53%) patients were treated with neoadjuvant chemotherapy. Bilateral nerve sparing was feasible in 13 (87%) patients, unilateral in 2 (13%). At postoperative day 10, only 3 (20%) patients continued intermittent self-catheterization. Before surgery, 1 (6.2%) patient had urodynamic symptoms of incontinence, and 3 (20%) had overactive bladder detrusor. Postoperative urodynamic study (median, 4 months; range, 3-6) showed reduced detrusor activity in 8 (53%), overactive detrusor in 4 (27%), and normal profile in 3 (20%) patients. Reduced bladder sensation was observed in 2 (12.5%), and residual urine more than 30% of bladder capacity in 2 (12.5%) patients, respectively. No patient showed de novo incontinence. Bladder compliance was unchanged. CONCLUSIONS: The separation of the hypogastric nerve from the parametrium is a feasible surgical step, which can be implemented in the radical hysterectomy technique in different clinical settings. The comparative urodynamic study showed a mild functional impairment in the early postoperative period. The most frequent finding was the reduced detrusor activity observed during the voiding phase, consistent with the straining needed to void reported in the questionnaire. These data suggest that a mild bladder impairment occurs despite the conservation of the hypogastric nerve.

Mechanical and microstructural characterization of titanium gr.5 parts produced by different manufacturing routes.

Since a few decades, the aircraft industry has shifted its preference for metal parts to titanium and its alloys, such as the high-strength titanium grade 5 alloy. Because of titanium grade 5 limited formability at ambient temperature, forming operations on this material requires high temperatures. In these conditions, a peculiar microstructure evolves as a result of the heating and deformation cycles, which has a significant impact on formability and product quality. On the other hand, additive manufacturing technologies, such as selective laser melting and electron beam melting, are increasingly being used and are replacing more traditional approaches such as machining and forging. Fundamental part characteristics such as mechanical and microstructural properties, geometric accuracy, and surface quality strongly depend on the selection of the manufacturing method. The authors of this paper seek to identify the strengths and limitations imposed by the intrinsic characteristics of different manufacturing alternatives for the production of parts of aeronautical significance, providing guidelines for the choice of the most appropriate manufacturing route for a given application and part design.

Experimental Characterization of the Torsional Damping in CFRP Disks by Impact Hammer Modal Testing.

Composite materials are widely used for their peculiar combination of excellent structural, mechanical, and damping properties. This work presents an experimental study on the dissipation properties of disk-shaped composite specimens exploiting vibration tests. Two different polymer matrix composites with the same number of identical laminae, but characterized by different stacking sequences, namely unidirectional and quasi-isotropic configurations, have been evaluated. An ad-hoc steel structure was designed and developed to reproduce an in-plane torsional excitation on the specimen. The main idea of the proposed approach relies on deriving the damping properties of the disks by focusing on the modal damping of the overall vibrating structure and, in particular, using just the first in-plane torsional deformation mode. Experimental torsional damping evaluations were conducted by performing vibrational hammer excitation on the presented setup. Two methods were proposed and compared, both relying on a single-degree-of-freedom (SDOF) approximation of the measured frequency response function (FRF).

Application of the Non-Destructive NIR Technique for the Evaluation of Strawberry Fruits Quality Parameters.

The determination of strawberry fruit quality through the traditional destructive lab techniques has some limitations related to the amplitude of the samples, the timing and the applicability along all phases of the supply chain. The aim of this study was to determine the main qualitative characteristics through traditional lab destructive techniques and Near Infrared Spectroscopy (NIR) in fruits of five strawberry genotypes. Principal Component Analysis (PCA) was applied to search for spectral differences among all the collected samples. A Partial Least Squares regression (PLS) technique was computed in order to predict the quality parameters of interest. The PLS model for the soluble solids content prediction was the best performing-in fact, it is a robust and reliable model and the validation values suggested possibilities for its use in quality applications. A suitable PLS model is also obtained for the firmness prediction-the validation values tend to worsen slightly but can still be accepted in screening applications. NIR spectroscopy represents an important alternative to destructive techniques, using the infrared region of the electromagnetic spectrum to investigate in a non-destructive way the chemical-physical properties of the samples, finding remarkable applications in the agro-food market.

Instance-based classifiers applied to medical databases: diagnosis and knowledge extraction.

OBJECTIVE: The aim of this paper is to study the feasibility and the performance of some classifier systems belonging to family of instance-based (IB) learning as second-opinion diagnostic tools and as tools for the knowledge extraction phase in the process of knowledge discovery in clinical databases. MATERIALS AND METHODS: We consider three clinical databases: one relating to the differential diagnosis of erythemato-squamous diseases, the second to the diagnosis of the onset of diabetes mellitus and the third dealing with a problem of diagnostic imaging in nuclear cardiology. We apply five IB classifiers to each database; two are based on exemplars, one is based on prototypes and two are hybrid. One of the latter classifiers is a new classifier introduced here and is called prototype exemplar learning classifier (PEL-C). We use cross-validation techniques to evaluate and compare the performances of several classifier systems as diagnostic tools, considering indexes such as accuracy, sensitivity, specificity, and conciseness of class representations. Moreover we analyze the number and the type of instances that represent the diagnostic classes learnt by each classifier to evaluate and compare their knowledge extraction capabilities. RESULTS: An examination of the experimental results shows that classifiers with the best classification performances are the optimized k-nearest neighbour classifier (k-NNC) and PEL-C. The k-NNC uses the highest number of representative instances, 100% of the entire database, whereas PEL-C uses a far lesser number of representative instances: equal, on the average, to the 3% of the database. As tools for knowledge extraction, we interpret the kind of class representations obtained by IB classifiers as a form of nosological knowledge. Additionally, we report the most interesting diagnostic class representations to be those extracted by PEL-C because they are composed of a mixture of abstracted prototypical cases (syndromes) and selected atypical clinical cases. CONCLUSION: This study shows that IB methods - most notably, the optimized k-NNC and the PEL-C - can be used and may be advantageous for clinical decision support systems and that IB classifiers can be used for nosological knowledge extraction. Because PEL-C uses more compact and potentially meaningful class descriptions, it is preferable when the diagnostic problem at-hand needs smaller storage space or for knowledge extraction itself. The complexity and responsibility of diagnostic practice requires that these results be confirmed further within other clinical domains.