Federated Machine Learning

In recent times, machine gaining knowledge has transformed areas such as processer visualisation, morphological and speech identification and processing. The implementation of machine learning is frim built on data and gathering the data in confidentiality disturbing circumstances. The studying of amalgamated systems and methods is an innovative area of modern technological field that facilitates the training within models without gathering the information. As an alternative to transferring the information, clients co-operate together to train a model be only delivering weights updates to the server. While this concerning privacy is better and more adaptable in some circumstances very expensive. This thesis generally introduces some of the fundamental theories, structural design and procedures of federated machine learning and its prospective in numerous applications. Some optimisation methods and some privacy ensuring systems like differential privacy also reviewed

Parvalbumin interneuron subpopulations: genetic characterization and hippocampal connectivity

In this thesis, I focus on the heterogeneity of hippocampal CA1, uncovering molecular diversity in developmentally defined groups of parvalbumin expressing basket cells. This molecular diversity is then integrated, through findings on differential connectivity, with previously described populations of CA1 principal cells and with cell-type specific manipulations during behavioral testing

Heterogeneidad tumoral en imágenes PET-CT

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Físicas, Departamento de Estructura de la Materia, Física Térmica y Electrónica, leída el 28/01/2021Cancer is a leading cause of morbidity and mortality [1]. The most frequent cancers worldwide are non–small cell lung carcinoma (NSCLC) and breast cancer [2], being their management a challenging task [3]. Tumor diagnosis is usually made through biopsy [4]. However, medical imaging also plays an important role in diagnosis, staging, response to treatment, and recurrence assessment [5]. Tumor heterogeneity is recognized to be involved in cancer treatment failure, with worse clinical outcomes for highly heterogeneous tumors [6,7]. This leads to the existence of tumor sub-regions with different biological behavior (some more aggressive and treatment-resistant than others) [8-10]. Which are characterized by a different pattern of vascularization, vessel permeability, metabolism, cell proliferation, cell death, and other features, that can be measured by modern medical imaging techniques, including positron emission tomography/computed tomography (PET/CT) [10-12]. Thus, the assessment of tumor heterogeneity through medical images could allow the prediction of therapy response and long-term outcomes of patients with cancer [13]. PET/CT has become essential in oncology [14,15] and is usually evaluated through semiquantitative metabolic parameters, such as maximum/mean standard uptake value (SUVmax, SUVmean) or metabolic tumor volume (MTV), which are valuables as prognostic image-based biomarkers in several tumors [16-17], but these do not assess tumor heterogeneity. Likewise, fluorodeoxyglucose (18F-FDG) PET/CT is important to differentiate malignant from benign solitary pulmonary nodules (SPN), reducing so the number of patients who undergo unnecessary surgical biopsies. Several publications have shown that some quantitative image features, extracted from medical images, are suitable for diagnosis, tumor staging, the prognosis of treatment response, and long-term evolution of cancer patients [18-20]. The process of extracting and relating image features with clinical or biological variables is called “Radiomics” [9,20-24]. Radiomic parameters, such as textural features have been related directly to tumor heterogeneity [25]. This thesis investigated the relationships of the tumor heterogeneity, assessed by 18F-FDG-PET/CT texture analysis, with metabolic parameters and pathologic staging in patients with NSCLC, and explored the diagnostic performance of different metabolic, morphologic, and clinical criteria for classifying (malignant or not) of solitary pulmonary nodules (SPN). Furthermore, 18F-FDG-PET/CT radiomic features of patients with recurrent/metastatic breast cancer were used for constructing predictive models of response to the chemotherapy, based on an optimal combination of several feature selection and machine learning (ML) methods...El cáncer es una de las principales causas de morbilidad y mortalidad. Los más frecuentes son el carcinoma de pulmón de células no pequeñas (NSCLC) y el cáncer de mama, siendo su tratamiento un reto. El diagnóstico se suele realizar mediante biopsia. La heterogeneidad tumoral (HT) está implicada en el fracaso del tratamiento del cáncer, con peores resultados clínicos para tumores muy heterogéneos. Esta conduce a la existencia de subregiones tumorales con diferente comportamiento biológico (algunas más agresivas y resistentes al tratamiento); las cuales se caracterizan por diferentes patrones de vascularización, permeabilidad de los vasos sanguíneos, metabolismo, proliferación y muerte celular, que se pueden medir mediante imágenes médicas, incluida la tomografía por emisión de positrones/tomografía computarizada con fluorodesoxiglucosa (18F-FDG-PET/CT). La evaluación de la HT a través de imágenes médicas, podría mejorar la predicción de la respuesta al tratamiento y de los resultados a largo plazo, en pacientes con cáncer. La 18F-FDG-PET/CT es esencial en oncología, generalmente se evalúa con parámetros metabólicos semicuantitativos, como el valor de captación estándar máximo/medio (SUVmáx, SUVmedio) o el volumen tumoral metabólico (MTV), que tienen un gran valor pronóstico en varios tumores, pero no evalúan la HT. Asimismo, es importante para diferenciar los nódulos pulmonares solitarios (NPS) malignos de los benignos, reduciendo el número de pacientes que van a biopsias quirúrgicas innecesarias. Publicaciones recientes muestran que algunas características cuantitativas, extraídas de las imágenes médicas, son robustas para diagnóstico, estadificación, pronóstico de la respuesta al tratamiento y la evolución, de pacientes con cáncer. El proceso de extraer y relacionar estas características con variables clínicas o biológicas se denomina “Radiomica”. Algunos parámetros radiómicos, como la textura, se han relacionado directamente con la HT. Esta tesis investigó las relaciones entre HT, evaluada mediante análisis de textura (AT) de imágenes 18F-FDG-PET/CT, con parámetros metabólicos y estadificación patológica en pacientes con NSCLC, y exploró el rendimiento diagnóstico de diferentes criterios metabólicos, morfológicos y clínicos para la clasificación de NPS. Además, se usaron características radiómicas de imágenes 18F-FDG-PET/CT de pacientes con cáncer de mama recurrente/metastásico, para construir modelos predictivos de la respuesta a la quimioterapia, combinándose varios métodos de selección de características y aprendizaje automático (ML)...Fac. de Ciencias FísicasTRUEunpu

Teaching Community College Students Strategies For Learning Unknown Words As They Read Expository Text

The study reported here investigated methods that enable college students to learn the meaning of unknown words as they read discipline specific academic text. The ability to read and comprehend text is known to be positively correlated with academic success. However that ability is challenging to college students in part because of the sophisticated vocabulary encountered in academic text. The study reported here utilized an experimental design. Forty one participants read specific passages aloud during three sessions. Participants were randomly assigned to one of four intervention groups to investigate alternative methods of learning the meaning of unknown words. In the Strategies group, participants learned the use of context cues, morphological cues, and syntactic cues. Participants in the Definition group learned to use researcher supplied definitions. In the Strategies plus Definition group, participants learned to use both the strategies and definitions. Using a constructivist framework to create meaning while interacting with text, these three groups had time for practice and received feedback. Participants in the fourth group, the Control group, engaged in discussion of the passages. Intervention and outcome measures examined word learning and comprehension. All participants completed a transfer task to investigate the effects of treatment on independent text reading. It was expected that participants in the intervention groups would outperform participants in the Control group, and that participants in the Strategies plus Definition group would outperform participants in the other two intervention groups. Results were mixed. Analyses of data revealed that participants in all three intervention groups demonstrated significantly better word learning and comprehension as measured by definition recall, CLOZE and response to comprehension questions than participants in the Control group. Other measures did not support these hypotheses. There were also interaction effects involving time with treatment groups performing differently on intervention and outcome measures than on transfer task measures. In general participants in the intervention groups performed better during the first three training texts than during the final transfer task. Additionally, participants in the intervention groups did not perform significantly better on the transfer task than participants in the control group. Thus the word learning treatments and their impact on comprehension did not generalize to a novel task as was hypothesized. Results of this study contribute to the research by helping us understand the benefit of methods that enable college students to access academic text. Use of definitions and to a lesser extent, use of strategies, appear to have a positive impact on word learning and comprehension. The use of a combination of strategies and definitions also appears to have a positive impact but, with mixed results, this awaits further study