Tesi: "Skinks Classification"

1

Al-Anezi, Yousuf. "Computer based learning environment for mathematical classification skills". Thesis, University of Leeds, 1994. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.666890.

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2

Viana, Joaquim Mesquita da Cunha. "Classification of skin tumours through the analysis of unconstrained images". Thesis, De Montfort University, 2009. http://hdl.handle.net/2086/2400.

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Skin cancer is the most frequent malignant neoplasm for Caucasian individuals. According to the Skin Cancer Foundation, the incidence of melanoma, the most malignant of skin tumours, and resultant mortality, have increased exponentially during the past 30 years, and continues to grow. [1]. Although often intractable in advanced stages, skin cancer in general and melanoma in particular, if detected in an early stage, can achieve cure ratios of over 95% [1,55]. Early screening of the lesions is, therefore, crucial, if a cure is to be achieved. Most skin lesions classification systems rely on a human expert supported dermatoscopy, which is an enhanced and zoomed photograph of the lesion zone. Nevertheless and although contrary claims exist, as far as is known by the author, classification results are currently rather inaccurate and need to be verified through a laboratory analysis of a piece of the lesion’s tissue. The aim of this research was to design and implement a system that was able to automatically classify skin spots as inoffensive or dangerous, with a small margin of error; if possible, with higher accuracy than the results achieved normally by a human expert and certainly better than any existing automatic system. The system described in this thesis meets these criteria. It is able to capture an unconstrained image of the affected skin area and extract a set of relevant features that may lead to, and be representative of, the four main classification characteristics of skin lesions: Asymmetry; Border; Colour; and Diameter. These relevant features are then evaluated either through a Bayesian statistical process - both a simple k-Nearest Neighbour as well as a Fuzzy k-Nearest Neighbour classifier - a Support Vector Machine and an Artificial Neural Network in order to classify the skin spot as either being a Melanoma or not. The characteristics selected and used through all this work are, to the author’s knowledge, combined in an innovative manner. Rather than simply selecting absolute values from the images characteristics, those numbers were combined into ratios, providing a much greater independence from environment conditions during the process of image capture. Along this work, image gathering became one of the most challenging activities. In fact several of the initially potential sources failed and so, the author had to use all the pictures he could find, namely on the Internet. This limited the test set to 136 images, only. Nevertheless, the process results were excellent. The algorithms developed were implemented into a fully working system which was extensively tested. It gives a correct classification of between 76% and 92% – depending on the percentage of pictures used to train the system. In particular, the system gave no false negatives. This is crucial, since a system which gave false negatives may deter a patient from seeking further treatment with a disastrous outcome. These results are achieved by detecting precise edges for every lesion image, extracting features considered relevant according to the giving different weights to the various extracted features and submitting these values to six classification algorithms – k-Nearest Neighbour, Fuzzy k-Nearest Neighbour, Naïve Bayes, Tree Augmented Naïve Bayes, Support Vector Machine and Multilayer Perceptron - in order to determine the most reliable combined process. Training was carried out in a supervised way – all the lesions were previously classified by an expert on the field before being subject to the scrutiny of the system. The author is convinced that the work presented on this PhD thesis is a valid contribution to the field of skin cancer diagnostics. Albeit its scope is limited – one lesion per image – the results achieved by this arrangement of segmentation, feature extraction and classification algorithms showed this is the right path to achieving a reliable early screening system. If and when, to all these data, values for age, gender and evolution might be used as classification features, the results will, no doubt, become even more accurate, allowing for an improvement in the survival rates of skin cancer patients.

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3

Wan, Fengkai. "Deep Learning Method used in Skin Lesions Segmentation and Classification". Thesis, KTH, Medicinsk teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-233467.

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Malignant melanoma (MM) is a type of skin cancer that is associated with a very poor prognosis and can often lead to death. Early detection is crucial in order to administer the right treatment successfully but currently requires the expertise of a dermatologist. In the past years, studies have shown that automatic detection of MM is possible through computer vision and machine learning methods. Skin lesion segmentation and classification are the key methods in supporting automatic detection of different skin lesions. Compared with traditional computer vision as well as other machine learning methods, deep neural networks currently show the greatest promise both in segmentation and classification. In our work, we have implemented several deep neural networks to achieve the goals of skin lesion segmentation and classification. We have also applied different training schemes. Our best segmentation model achieves pixel-wise accuracy of \textbf{0.940}, Dice index of \textbf{0.867} and Jaccard index of \textbf{0.765} on the ISIC 2017 challenge dataset. This surpassed the official state of the art model whose pixel-wise accuracy was 0.934, Dice index 0.849 and Jaccard Index 0.765. We have also trained a segmentation model with the help of adversarial loss which improved the baseline model slightly. Our experiments with several neural network models for skin lesion classification achieved varying results. We also combined both segmentation and classification in one pipeline meaning that we were able to train the most promising classification model on pre-segmented images. This resulted in improved classification performance. The binary (melanoma or not) classification from this single model trained without extra data and clinical information reaches an area under the curve (AUC) of 0.684 on the official ISIC test dataset. Our results suggest that automatic detection of skin cancers through image analysis shows significant promise in early detection of malignant melanoma.

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4

Dhinagar, Nikhil J. "Non-Invasive Skin Cancer Classification from Surface Scanned Lesion Images". Ohio University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1366384987.

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5

Moulis, Armand. "Automatic Detection and Classification of Permanent and Non-Permanent Skin Marks". Thesis, Linköpings universitet, Datorseende, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-138132.

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When forensic examiners try to identify the perpetrator of a felony, they use individual facial marks when comparing the suspect with the perpetrator. Facial marks are often used for identification and they are nowadays found manually. To speed up this process, it is desired to detect interesting facial marks automatically. This master thesis describes a method to automatically detect and separate permanent and non-permanent marks. It uses a fast radial symmetry algorithm as a core element in the mark detector. After candidate skin mark extraction, the false detections are removed depending on their size, shape and number of hair pixels. The classification of the skin marks is done with a support vector machine and the different features are examined. The results show that the facial mark detector has a good recall while the precision is poor. The elimination methods of false detection were analysed as well as the different features for the classifier. One can conclude that the color of facial marks is more relevant than the structure when classifying them into permanent and non-permanent marks.
När forensiker försöker identifiera förövaren till ett brott använder de individuella ansiktsmärken när de jämför den misstänkta med förövaren. Dessa ansiktsmärken identifieras och lokaliseras oftast manuellt idag. För att effektivisera denna process, är det önskvärt att detektera ansiktsmärken automatiskt. I rapporten beskrivs en framtagen metod som möjliggör automatiskt detektion och separation av permanenta och icke-permanenta ansiktsmärken. Metoden som är framtagen använder en snabb radial symmetri algoritm som en huvuddel i detektorn. När kandidater av ansiktsmärken har tagits, elimineras alla falska detektioner utifrån deras storlek, form och hårinnehåll. Utifrån studiens resultat visar sig detektorn ha en god känslighet men dålig precision. Eliminationsmetoderna av falska detektioner analyserades och olika attribut användes till klassificeraren. I rapporten kan det fastställas att färgskiftningar på ansiktsmärkena har en större inverkan än formen när det gäller att sortera dem i permanenta och icke-permanenta märken.

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Ridell, Patric, e Henning Spett. "Training Set Size for Skin Cancer Classification Using Google’s Inception v3". Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209443.

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Today, computer aided diagnosis (CADx) is a common occurrence in hospitals. With image recognition, computers are able to detect signs of breast cancer and different kinds of lung diseases. For a convolutional neural network (CNN) that classifies images, the accuracy depends on the amount of data it is trained on and performs better as the amount of training data increase. This introduces a need for relevant images for the classes the classifier is supposed to differentiate between. However, when input data is increased, so does the computational cost, leading to a trade-off between accuracy and computational time. In a study by Cho et al. the accuracy improvement stagnates, when comparing the accuracy with different amounts of training data. This creates interests in finding that point of stagnation, since further increase of input data would lead to longer computational time but little effect on the accuracy. In this study, the pre-trained CNN Google Inception v3 is retrained with various amounts of skin lesion images. The objective is to detect whether the image represents a benign nevus or malignant melanoma. When comparing the accuracy for these different training sessions it is concluded that the accuracy increases when trained with more data. However, a stagnation point for the accuracy is not found.
Datorstödd diagnostik (CADx) är idag vanligt förekommande inom sjukvården. Med datorseende är det möjligt att undersöka huruvida bilder påvisar tecken för till exempel bröstcancer och lungsjukdomar. Träffsäkerheten för convolutional neural networks (CNN) klassificering av sjukdomar beror till viss del på hur mycket data det tränats på. Stora datamängder är en förutsättning för att CNN ska kunna ge pålitliga diagnoser. En stor mängd indata innebär dock att bräkningstiden ökar. Detta medför att det kan behöva göras en avvägning mellan träffsäkerhet och beräkningstid. Cho et al. har i en studie visat att träffsäkerhetens förbättring stagnerar när mängden indata ökar. Det finns därför ett intresse i att hitta den punkt där träffsäkerheten stagnerar, eftersom ytterligare ökning av indata skulle innebära längre beräkningstid men med liten förbättring i träffsäkerhet. I denna uppsats tränas Googles förtränade CNN om på varierade mängder bilder på hudfläckar, i syfte att avgöra om en bild föreställande en hudfläck visar tecken på malignt melanom eller om den bedöms vara godartad. Studiens resultat ger indikationer på att träffsäkerheten för klassificeraren förbättras när mängden träningsdata ökar. Däremot finns inte underlag för att fastställa en punkt då träffsäkerheten stagnerar.

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7

Boman, Joakim, e Alexander Volminger. "Evaluating a deep convolutional neural network for classification of skin cancer". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-229740.

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Computer-aided diagnosis (CAD) has become an important part of themedical field. Skin cancer is a common and deadly disease that a CADsystem could potentially detect. It is clearly visible on the skin andtherefore only images of skin lesions could be used in order to pro-vide a diagnosis. In 2017, a research group at Stanford University de-veloped a deep convolutional neural network (CNN) that performedbetter than dermatologists during classification of skin lesions.This thesis makes an attempt at implementing the method pro-vided in the Stanford report and evaluate the performance of the CNNduring classification of skin lesion comparisons not tested in their study.The previously unseen binary classification use cases are melanomaversus solar lentigo and melanoma versus seborrheic keratosis. Usingtransfer learning, Inception v3 was trained for various skin lesions.The CNN was trained with 16 training classes. During validation ofthe CNN, an accuracy of 68.3% was achieved during a 3-way classi-fication. Testing the same comparisons as the Stanford study an ac-curacy of 71% was achieved for melanoma versus nevus and 91% forseborrheic keratosis versus basal and squamous cell carcinoma. Theaccuracy results for the new comparisons were 84% for seborrheic ker-atosis versus melanoma and 83% for solar lentigo versus melanoma.The results suggest that out of the binary classifications performedin this study, nevus versus melanoma is the most difficult for the CNN.It should be noted that our results were different from the Stanfordstudy and that more statistical methods should have been used whenobtaining the results
Computer-aided diagnosis (CAD) har blivit en viktigt del av det medi-cinska området. Hudcancer är en vanlig och dödlig sjukdom som ett CAD system potentiellt kan upptäcka. Den är klart synlig på hudenoch därför skulle endast bilder av hudskador kunna användas för attge en diagnos. År 2017 utvecklade en forskningsgrupp från StanfordUniversity ett deep convolutional neural network (CNN) som preste-rade bättre än dermatologer vid klassificering av hudskador. Detta kandidatexamensarbete gör ett försök till att implementerametoden tillhandahållen i Stanford rapporten och utvärdera CNN:etsresultat vid klassifikation av hudskador som inte testades i deras stu-die. De binära fall som tidigare inte har testas är melanoma emot solarlentigo och melanoma emot seborrheic keratosis. Med hjälp av transferlearning tränades Inception v3 för olika hudskador. CNN:et tränadesmed 16 typer av hudförändringar. I valideringsprocessen uppmättesen korrekthet på 68.3% under 3-vals klassifikation. I tester av sammatyp av jämförelser som i Stanford studien uppmätes en korrekthet på71% för melanoma emot nevus och 91% för seborrheic keratosis emotbasal and squamous cell carcinoma. Resultatet av de nya jämförelser-na var 84% för seborrheic keratosis emot melanoma och 83% för solarlentigo emot melanoma. Resultaten tyder på att av de binära klassificeringarna utförda idenna studie, är nevus emot melanoma den svårast för CNN:et. Detbör noteras att våra resultat skilde sig från Stanford studien och attmer stat

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8

Sahlgren, Michaela, e Nour Alhunda Almajni. "Skin Cancer Image Classification with Pre-trained Convolutional Neural Network Architectures". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-259622.

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In this study we compare the performance of different pre-trained deep convolutional neural network architectures on classification of skin lesion images. We analyse the ISIC skin cancer image dataset. Our results indicate that the architectures analyzed achieve similar performance, with each algorithm reaching a mean five-fold cross-validation ROC AUC value between 0.82 and 0.89. The VGG-11 architecture achieved highest performance, with a mean ROC AUC value of 0.89, despite the fact that it performs considerably worse than some of other architectures on the ILSVRC task. Overall, our results suggest that the choice of architecture may not be as crucial on skin-cancer classification compared with the ImageNet classification problem.
I denna studie jämför vi hur väl olika förtränade konvolutionella neurala nätverksarkitekturer klassificerar bilder av potentiellt maligna födelsemärken. Detta med hjälp av datasetet ISIC, innehållande bilder av hudcancer. Våra resultat indikerar att alla arkitekturer som undersöktes gav likvärdiga resultat vad gäller hur väl de kan avgöra huruvida ett födelsemärke är malignt eller ej. Efter en femfaldig korsvalidering nådde de olika arkitekturerna ett ROC AUC-medelvärde mellan 0.82 och 0.89, där nätverket Vgg-11 gjorde allra bäst ifrån sig. Detta trots att samma nätvärk är avsevärt sämre på ILSVRC. Sammantaget indikterar våra resultat att valet av arkitektur kan vara mindre viktigt vid bildklassificering av hudcancer än vid klassificering av bilder på ImageNet.

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9

Almasiri, osamah A. "SKIN CANCER DETECTION USING SVM-BASED CLASSIFICATION AND PSO FOR SEGMENTATION". VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5489.

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Various techniques are developed for detecting skin cancer. However, the type of maligned skin cancer is still an open problem. The objective of this study is to diagnose melanoma through design and implementation of a computerized image analysis system. The dataset which is used with the proposed system is Hospital Pedro Hispano (PH²). The proposed system begins with preprocessing of images of skin cancer. Then, particle swarm optimization (PSO) is used for detecting the region of interest (ROI). After that, features extraction (geometric, color, and texture) is taken from (ROI). Lastly, features selection and classification are done using a support vector machine (SVM). Results showed that with a data set of 200 images, the sensitivity (SE) and the specificity (SP) reached 100% with a maximum processing time of 0.03 sec.

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Inal, Aydin. "Practical science process skills in physics, with special reference to test item assessment and classification". Master's thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/11566.

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Bibliography: leaves 207-218.
This study describes the development, validation, classification, administration and assessment of a compact programme of ten core practical task items chosen from a pool of 33 practical tasks developed for the purpose of this study in basic school physical science. The practical items encouraged and measured various science process skills laid out in the South African Revised National Curriculum Statement Draft. The derivation and classification of the specially designed diagnostic practical task items by experienced lecturers, teachers and academics constitutes an original and crucial part of the study. The objective is to assess the consensus of juries of four to eleven expert science educators on classification of the ten core practical activities, matching the categories. The investigation establishes whether there is a perceived relevant match or a perceived "irrelevant" mismatch between the science process skills tested by the current experimental programme of practical items and the descriptive theories of practical science and its classification schemes and criteria proposed by (a) Franus (1992), (b) Gardner (1983), (c) White (1988), (d) Solomon (1998), (e) Lock (1990), (t) Kapenda, Kandjeo-Marenga, Gaoseb, Kasanda and Lubben's (2001) the Cambridge-based International General Certificate of Education after Millar, Ie Marechal and Tiberghiea (1999), (g) Race (1997) and (h) OBE (Revised National Curriculum Statement Draft, 2001). Lock's assessment framework for practical tasks was found to be the most relevant scheme among the others. The study also identified eight process skills that are highly relevant to practical tasks of the compact programme. These skills included: (a) comprehension skills; (b) recognising given item of apparatus; (c) following instructions; (d) carrying out tasks and handling science apparatus; (e) observation skills; (t) interpretation of the observations; (g) making predictions; and (h) reporting and communicating scientific information.

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Samuelsson, Emil. "Classification of skin pixels in images : Using feature recognition and threshold segmentation". Thesis, Umeå universitet, Institutionen för datavetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-155400.

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The purpose of this report is to investigate and answer the research question: How can current skin segmentation thresholding methods be improved in terms of precision, accuracy, and efficiency by using feature recognition, pre- and post-processing? In this work, a novel algorithm is presented for classification of skin pixels in images. Different pre-processing methods were evaluated to improve the overall performance of the algorithm. Mainly, the methods of image smoothing, and histogram equalization were tested. Using a Gaussian kernel and contrast limited adaptive histogram equalization (CLAHE) was found to give the best result. A face recognition technique based on learned face features were used to identify a skin color range for each image. Threshold segmentation was then used, based on the obtained skin color range, to extract a skin map for each image. The skin maps were improved by testing a morphology method called closing and by using contour detection for an elimination of large false skin structures within skin regions. The skin maps were then evaluated by calculating the precision, recall, accuracy, and f-measure using a ground truth dataset called Pratheepan. This novel approach was compared to previous work in the field and obtained a considerable higher result. Thus, the algorithm is an improvement compared to previous work within the field.

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Poncet, T., e Cédric Vigier. "Traceability of hides and skins - 212: from field to leather". Verein für Gerberei-Chemie und -Technik e. V, 2019. https://slub.qucosa.de/id/qucosa%3A34315.

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Content: Quality of leather is deeply dependant on the origin of the livestock including breeding, transportation and slaughter. Ten years ago, the French leather industry have commissioned CTC, the French Leather, leather goods and footwear research centre to improve the quality of hides and skins. In order to improve raw material, a unitary link is required between the quality of leather and its origin that is to say the raw material. This was the beginning of a huge project: traceability of hides and skins through the supply chain, from breeding to wet-blue (and even leather). Data is captured from the animal’s ear tag at the point of slaughter which is then transfer on to a paper bar code. Hides and skins traders will then transfer definitively the code from the paper tag to the hides or skins thanks to an automatic high-pressure CO2 marking device on the hair side of the fresh or salted hide in the neck region. That unitary traceability is resistant to water, acid, alcalis, grease, solvents but also mechanical impacts such as splitting, shaving and even buffing. It is visible throughout all the process and fast enough. Once the permanent number code has been added, it can be visually or automatically read throughout the subsequent tanning process steps. The automatic code reader takes the algorithm of the number and the data is collected by mean of artificial intelligence. This technology has been implemented by several abattoirs, trader and tanners. Traceability is the essential tool for quality management throughout the supply chain. It helps the identification of the origin of defects for improvement and provides the origin of grade 1 hides and skins. This realistic industrial solution is a major issue for the leather industry whether it is for the improvement of quality or mastery of the supply chain and sustainability. Take-Away: In order to improve the quality of raw material, a unitary link is required between the quality of leather and its origin that is to say the raw material. This is the objective of that project: traceability of hides and skins through the supply chain, from breeding to wet-blue (and even leather) thanks to CO2 laser marquing.

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Nylund, Andreas. "To be, or not to be Melanoma : Convolutional neural networks in skin lesion classification". Thesis, KTH, Medicinsk teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-190000.

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Machine learning methods provide an opportunity to improve the classification of skin lesions and the early diagnosis of melanoma by providing decision support for general practitioners. So far most studies have been looking at the creation of features that best indicate melanoma. Representation learning methods such as neural networks have outperformed hand-crafted features in many areas. This work aims to evaluate the performance of convolutional neural networks in relation to earlier machine learning algorithms and expert diagnosis. In this work, convolutional neural networks were trained on datasets of dermoscopy images using weights initialized from a random distribution, a network trained on the ImageNet dataset and a network trained on Dermnet, a skin disease atlas. The ensemble sum prediction of the networks achieved an accuracy of 89.3% with a sensitivity of 77.1% and a specificity of 93.0% when based on the weights learned from the ImageNet dataset and the Dermnet skin disease atlas and trained on non-polarized light dermoscopy images. The results from the different networks trained on little or no prior data confirms the idea that certain features are transferable between different data. Similar classification accuracies to that of the highest scoring network are achieved by expert dermatologists and slightly higher results are achieved by referenced hand-crafted classifiers. The trained networks are found to be comparable to practicing dermatologists and state-of-the-art machine learning methods in binary classification accuracy, benign – melanoma, with only little pre-processing and tuning.

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Akhavan, S., C. Uran, B. Bozok, K. Gungor, Y. Kelestemur, V. Lesnyak, N. Gaponik, A. Eychmüller e H. V. Demir. "Flexible and fragmentable tandem photosensitive nanocrystal skins". Royal Society of Chemistry, 2016. https://tud.qucosa.de/id/qucosa%3A36332.

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We proposed and demonstrated the first account of large-area, semi-transparent, tandem photosensitive nanocrystal skins (PNSs) constructed on flexible substrates operating on the principle of photogenerated potential buildup, which avoid the need for applying an external bias and circumvent the currentmatching limitation between junctions. We successfully fabricated and operated the tandem PNSs composed of single monolayers of colloidal water-soluble CdTe and CdHgTe nanocrystals (NCs) in adjacent junctions on a Kapton polymer tape. Owing to the usage of a single NC layer in each junction, noise generation was significantly reduced while keeping the resulting PNS films considerably transparent. In each junction, photogenerated excitons are dissociated at the interface of the semi-transparent Al electrode and the NC layer, with holes migrating to the contact electrode and electrons trapped in the NCs. As a result, the tandem PNSs lead to an open-circuit photovoltage buildup equal to the sum of those of the two single junctions, exhibiting a total voltage buildup of 128.4 mV at an excitation intensity of 75.8 μW cm⁻² at 350 nm. Furthermore, we showed that these flexible PNSs could be bent over 3.5 mm radius of curvature and cut out in arbitrary shapes without damaging the operation of individual parts and without introducing any significant loss in the total sensitivity. These findings indicate that the NC skins are promising as building blocks to make low-cost, flexible, large-area UV/visible sensing platforms with highly efficient full-spectrum conversion.

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Nurrito, Eugenio. "Scattering networks: efficient 2D implementation and application to melanoma classification". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/12261/.

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Machine learning is an approach to solving complex tasks. Its adoption is growing steadily and the several research works active on the field are publishing new interesting results regularly. In this work, the scattering network representation is used to transform raw images in a set of features convenient to be used in an image classification task, a fundamental machine learning application. This representation is invariant to translations and stable to small deformations. Moreover, it does not need any sort of training, since its parameters are fixed and only some hyper-parameters must be defined. A novel, efficient code implementation is proposed in this thesis. It leverages on the power of GPUs parallel architecture in order to achieve performance up to 20× faster than earlier codes, enabling near real-time applications. The source code of the implementation is also released open-source. The scattering network is then applied on a complex dataset of textures to test the behaviour in a general classification task. Given the conceptual complexity of the database, this unspecialized model scores a mere 32.9 % of accuracy. Finally, the scattering network is applied to a classification task of the medical field. A dataset of images of skin lesions is used in order to train a model able to classify malignant melanoma against benign lesions. Malignant melanoma is one of the most dangerous skin tumor, but if discovered in early stage there are generous probabilities to recover. The trained model has been tested and an interesting accuracy of 70.5 % (sensitivity 72.2 %, specificity 70.0 %) has been reached. While not being values high enough to permit the use of the model in a real application, this result demonstrates the great capabilities of the scattering network representation.

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Rastgoo, Mojdeh. "An approach to melanoma classification exploiting polarization information". Doctoral thesis, Universitat de Girona, 2016. http://hdl.handle.net/10803/392141.

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Malignant melanoma is the deadliest of skin cancers and causes the majority of deaths in comparison to other skin-related malignancies. Yet it is the most treatable type of cancer, thanks to its early diagnosis. Subsequently, early diagnosis is crucial for patient survival rate and numerous Computer-Aided Diagnosis (CAD) systems have been proposed by the research community to assist dermatologists in early diagnosis. These systems are based on the most common skin imaging modality, cross-polarized dermoscopy. Cross-polarized dermoscopes (PD) allow for the visualization of the subsurface anatomic structure of the epidermis and papillary dermis and eliminate the specular reflection of the surface. Although this modality has been used extensively, the full potential of polarized measurements has not been realized in the field of skin imaging. This research first extensively analyzes different aspects of the automated classification of pigmented skin lesions (PSLs) and proposes a CAD system for automatic recognition of melanoma lesions based on the PD images. The proposed CAD system is evaluated over extensive experiments on two dermoscopic datasets. Later for further investigation of polarized imaging, a novel partial Stokes polarimeter system is proposed. This system is able to acquire polarized images of in-vivo PSLs and capture the epidermis and superficial dermal layers, where skin lesions are often originated. The polarized and dermoscopy properties of the acquired images are then analyzed to propose a new CAD system based on image polarimetry. The initial tests with the first prototype of Stokes polarimeter revealed the potential and benefits of such systems for providing additional information beyond RGB images acquired with PD devices. In order to acquire a wider clinical dataset and identify the drawbacks of the first prototype, this device is currently being used in the Melanoma Unit at the Clinic Hospital of Barcelona.
El melanoma maligne és el més mortal dels càncers de pell i provoca la majoria de les morts en comparació amb altres tumors malignes relacionats amb la pell. No obstant això, és el tipus més tractable de càncer, gràcies al seu diagnòstic precoç. Per tant, el diagnòstic precoç és crucial per a la supervivència dels pacients. Nombrosos sistemes de diagnòstic assistit per ordinador (CAD, de l’anglés Computer Aided Diagnosis) han estat proposats per la comunitat investigadora per ajudar als dermatòlegs en el diagnósstic precoç. Aquests sistemes es basen en la modalitat més emprada d’adquisició d’imatges de pell, la dermatoscòpia de polarització creuada (PD, de l’angl`es Polarized Dermatoscopy). La dermatoscòpia de polarització creuada permet la visualització de l’estructura anatòmica del subsòl de l’epidermis i la dermis papil·lar, eliminant les reflexions especulars de la superfíıcie. Tot i que aquesta modalitat ha estat utilitzada àmpliament, no tot el potencial de les mesures polaritzades ha estat aprofitat en el camp de la imatge de pell. Aquest treball de recerca analitza, en primer lloc, diversos aspectes de la classificació automatitzada de les lesions cutànies pigmentades (PSLs, de l’anglès Pigmented Skin Lesions) i proposa un sistema CAD per al reconeixement automàtic de lesions de melanoma en base a les imatges de PD. El sistema CAD proposat es va avaluar en el transcurs d’extensos experiments en dos conjunts de dades dermatoscòpiques. Posteriorment, en una investigació més extensa pel que fa a la formació d’imatges polaritzades, es proposa un nou sistema de partial Stokes polarimeter. Aquest sistema és capaç d’adquirir imatges polaritzades dels PSLs en viu, capturant l’epidermis i les capes d´ermiques superficials, on sovint s’originen les lesions de la pell. Les propietats de polarització i dermoscopia de la imatge són analitzades a continuació, proposant un nou sistema CAD basat en la imatge de polarimetria. Les proves inicials, amb el primer prototip d’Stokes polarimeter, han revelat el potencial i els beneficis de tals sistemes per proporcionar informació addicional més enllà de les imatges RGB adquirides amb dispositius PD. Per tal d’adquirir un conjunt de dades clíniques més ampli i identificar els inconvenients del primer prototip, aquest dispositiu s’està utilitzant actualment a la Unitat de Melanoma de l’Hospital Clínic de Barcelona.

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17

Sharif, Monier A. Mohamed. "Epidemiology of skin tumor entities according to the new WHO classification in dogs and cats". Giessen VVB Laufersweiler, 2006. http://geb.uni-giessen.de/geb/volltexte/2006/2981/index.html.

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18

Haggerty, Juliana. "Computer aided classification of histopathological damage in images of haematoxylin and eosin stained human skin". Thesis, University of Newcastle upon Tyne, 2016. http://hdl.handle.net/10443/3288.

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Excised human skin can be used as a model to assess the potency, immunogenicity and contact sensitivity of potential therapeutics or cosmetics via the assessment of histological damage. The current method of assessing the damage uses traditional manual histological assessment, which is inherently subjective, time consuming and prone to intra-observer variability. Computer aided analysis has the potential to address issues surrounding traditional histological techniques through the application of quantitative analysis. This thesis describes the development of a computer aided process to assess the immune-mediated structural breakdown of human skin tissue. Research presented includes assessment and optimisation of image acquisition methodologies, development of an image processing and segmentation algorithm, identification and extraction of a novel set of descriptive image features and the evaluation of a selected subset of these features in a classification model. A new segmentation method is presented to identify epidermis tissue from skin with varying degrees of histopathological damage. Combining enhanced colour information with general image intensity information, the fully automated methodology segments the epidermis with a mean specificity of 97.7%, a mean sensitivity of 89.4% and a mean accuracy of 96.5% and segments effectively for different severities of tissue damage. A set of 140 feature measurements containing information about the tissue changes associated with different grades of histopathological skin damage were identified and a wrapper algorithm employed to select a subset of the extracted features, evaluating feature subsets based their prediction error for an independent test set in a Naïve Bayes Classifier. The final classification algorithm classified a 169 image set with an accuracy of 94.1%, of these images 20 were an unseen validation set for which the accuracy was 85.0%. The final classification method has a comparable accuracy to the existing manual method, improved repeatability and reproducibility and does not require an experienced histopathologist.

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19

Pulido, Kelly Cristina Strazzieri. "Adaptação cultural e validação do instrumento \"Star Skin Tear Classification System\", para a língua portuguesa no Brasil". Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/7/7139/tde-23122010-103305/.

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O objetivo do estudo foi realizar a adaptação cultural do STAR Skin Tear Classification System, para a língua portuguesa no Brasil e testar a validade de conteúdo e a confiabilidade inter-observadores da versão adaptada. O estudo é do tipo metodológico com abordagem quantitativa. A adaptação cultural foi desenvolvida em três fases: tradução, avaliação por comitê de juízes e retro-tradução. Foram testadas duas propriedades de medida: validade de conteúdo e confiabilidade inter-observadores. Para as análises estatísticas foi utilizado o índice kappa ponderado. A versão adaptada para o português obteve um nível regular de concordância (kw = 0,286), embora estatisticamente significativo (p = 0,000), quando de sua aplicação por enfermeiros em fotografias de lesão por fricção. Quando de sua aplicação na prática clínica, a versão adaptada em português obteve um nível moderado e estatisticamente significativo de concordância (kw = 0,596; p < 0,001). O estudo sobre o processo de adaptação cultural e validação das propriedades de medida do STAR Skin Tear Classification System possibilitou atestar a validade de conteúdo e a confiabilidade inter-observadores da versão adaptada para uso na língua portuguesa do Brasil
This study aims to perform a cultural adaptation of the STAR Skin Tear Classification System, to the Portuguese language spoken in Brazil and to test its contents validity and the reliability in the translated version. This is a methodological type of study with a quantitative approach. The cultural adaptation was developed in three stages: translation, evaluation by a judges committee and back translation. Two measures were tested: validity and reliability. The statistical analysis used the weighted kappa index. The adapted version had a regular concordance level (kw = 0,286), although statistically significant (p < 0,000) when tested by nurses in skin tears photographs. When tested in clinical practice, the adapted version achieved a moderate and statistically significant concordance level (kw = 0,596; p < 0,001). The study about the cultural adaptation process and validation of the measurements properties of the STAR Skin Tear Classification System confirmed the adapted Brazilian Portuguese version content validity and reliability

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20

Engelbrecht, Hanlie M. "Systematics of the Cape legless skink Acontias meleagris species complex". Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/79789.

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Thesis (MSc)--Stellenbosch University, 2013.
This study examined the biogeography and taxonomic status of the Cape legless skink, Acontias meleagris species complex using phylogenetic analyses, population genetics, demographic history aspects, time of lineage diversification estimation, environmental statistic analyses and a morphological evaluation. A total of 231 specimens from 55 localities were collected from the entire known distribution range of the A. meleagris complex throughout the Eastern, Northern and Western Cape, South Africa. Partial sequence data were collected from two mitochondrial DNA loci, 16S rRNA and cytochrome oxidase subunit one (COI), and one protein-coding nuclear DNA locus, exophilin 5 (EXPH 5). DNA sequences were analyzed for phylogenetic methods and biogeographical dating, while population genetic analyses were conducted on the COI sequences. Geographical boundaries amongst cryptic lineages were determined and evolutionary drivers of cladogenesis within the species complex were inferred. Marked genetic structure was observed within the A. meleagris complex, and five clades were retrieved, most of which were statistically well supported. These five clades were also evident within the haplotypic analyses and were characterized by demographic stability. Lineage diversification and the current biogeographical patterning observed for lineages within the A. meleagris species complex reflect the impact of sea level oscillations on historical coastal habitat availability. Additional historical evolutionary drivers within this subterranean species complex were inferred and discussed. The five clades within this species complex were considered discrete species, characterised by phylogenetic and biogeographic distinctiveness. While, morphological characters that could be used to identify the five species demonstrated widespread overlap for morphometric and meristic characters as well as colour pattering. Consequently, the phylogenetic species concept was employed for a taxonomical revision of A. meleagris sensu lato. Here, three of the previously recognised subspecies A. m. meleagris, A. m. orientalis and A. m. orientalis–'lineicauda' were elevated to full species, and two new species A. caurinus sp. nov. and A. parilis sp. nov. were described.
National Research Foundation (NRF)

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21

Curtaz, Kimjana, Barbara Dunkel, Ann-Katrin Jack, Davina Jacob, Timmo Joseph, Katrin Sach, Henning Staar, Caroline Verfürth e Monique Janneck. "Political Skills in virtuellen Netzwerken". Technische Universität Dresden, 2011. https://tud.qucosa.de/id/qucosa%3A28073.

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22

Guichard, Alexandre. "La puissance des dermocorticoïdes : Vers une nouvelle approche de la classification". Thesis, Besançon, 2014. http://www.theses.fr/2014BESA3014/document.

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Chaque cadre doit contenir un résumé de 1700 caractères maximum, espaces compris. En cas de dépassement, lacoupure sera automatique.Le doctorant adresse son texte sous forme électronique selon les recommandations de la bibliothèqueLes dermocorticoïdes (DC) sont des anti-inflammatoires topiques largement prescrits pour traiter de nombreuses dermatoses. Actuellement, leur puissance, classée en quatre groupes, est déterminée par leur effet vasoconstricteur basé sur un test empirique obsolète, subjectif et réducteur vis-à-vis des nombreux autres effets des DC. L'objectif de ce travail était de comparer la puissance des DC dans trois de leurs indications et de la confronter à la classification actuelle:• Anti-inflammatoire. Une étude clinique randomisée contrôlée en double aveugle a été réalisée sur 21 patients allergiques aunickel traités par quatre DC. Les différents paramètres de l'inflammation ont été mesurés objectivement par des outils debiométrologie. La hiérarchisation de la puissance des DC variait en fonction du temps et des paramètres de l'inflammationétudiés. Sur ce modèle, la classification peut être simplifiée en trois groupes.• Antiprolifératif. L'efficacité de six DC sur la prolifération, le cycle cellulaire et l'apoptose de kératinocytes hyperproliféranten culture a été comparée. La classification de la puissance antiproliférative divergeait de la classification actuelle.• Antiprurigineux à médiation histaminique. L'effet anti-histaminolibérateur de huit DC a été comparé sur des explants depeau à l'aide d'un dosage par microdialyse sous-cutanée. La classification de la puissance anti-histaminolibératrice divergeaitde la classification actuelle.Nous avons démontré que la classification actuelle des DC n'est pas exactement corrélée à leur effet anti-inflammatoire dansl'allergie de contact, à leur effet antiprolifératif ainsi qu'à leur effet sur la libération d'histamine. Notre nouvelle approche est deparler des puissances DC au pluriel. Une classification multimodale adaptée à la situation clinique permettrait une prescriptionplus efficiente et limiterait les échecs et effets indésirables
Topical corticosteroids (TCS) are topical anti-inflammatory widely prescribed to treat many skin diseases. Currently, their potency, ranged into four groups, is determined by their vasoconstrictor effect based on an empirical, outdated, subjective and too restrictive test. The aim of this work was to compare specifically the potency of TCS in three situations and to compare it to the current classification:• Anti-inflammatory. A randomized controlled double-blind clinical study was performed on 21 nickel-sensitive patientstreated by four TCS. Different inflammation parameters were objectively assessed with bioengineering tools. The ranking ofTCS potency varied according to time and parameters of the inflammation studied. According to this model, the classificationmay be simplified into three groups.• Antiproliferative. The efficacy of six TCS on immortal keratinocytes proliferation, cell cycle and apoptosis was compared. Theclassification of the antiproliferative potency differed from the current classification.• Antipruritic histamine-mediated. The histamine-release inhibition of eight TCS was compared on skin explants by asubcutaneous microdialysis dosage. The classification of the histamine-release inhibition potency differed from the currentclassification.We have demonstrated that the current classification of TCS potency is not strictly correlated to their anti-inflammatory effect in the context of allergie contact dermatitis, to their antiproliferative effect and to their histamine-release inhibitor effect. Our new approach is to talk about TCS potencies in the plural. A specifie classification adapted to the therapeutic target is needed to be more efficient and reduce side effects

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23

Breugnot, Josselin. "Modélisation surfacique et volumique de la peau : classification et analyse couleur". Phd thesis, Université Jean Monnet - Saint-Etienne, 2011. http://tel.archives-ouvertes.fr/tel-00693348.

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Grâce aux innovations technologiques récentes, l'exploration cutanée est devenue de plus en plus facile et précise. Le relevé topographique de la surface de peau par projection de franges ainsi que l'exploration des structures intradermiques par microscopie confocale in-vivo en sont des exemples parfaits. La mise en place de ces techniques et les développements sont présentés dans cette thèse. L'apport de l'imagerie est évident tant pour le traitement des acquisitions de ces appareils que pour l'évaluation de paramètres cutanés à partir de photographie par exemple. L'extension du modèle LIP niveaux de gris à la couleur a été réalisée pour apporter une évaluation proche de celle d'un expert grâce aux fondements logarithmiques du modèle, proches de la vision humaine. Enfin, la classification de données dans une image, sujet omniprésent dans le traitement d'images, a été abordée par les classifications hiérarchiques ascendantes, utilisant un cadre mathématique rigoureux grâce aux métriques ultramétriques.

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24

Li, Xiang. "Depth data improves non-melanoma skin lesion segmentation and diagnosis". Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/5867.

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Examining surface shape appearance by touching and observing a lesion from different points of view is a part of the clinical process for skin lesion diagnosis. Motivated by this, we hypothesise that surface shape embodies important information that serves to represent lesion identity and status. A new sensor, Dense Stereo Imaging System (DSIS) allows us to capture 1:1 aligned 3D surface data and 2D colour images simultaneously. This thesis investigates whether the extra surface shape appearance information, represented by features derived from the captured 3D data benefits skin lesion analysis, particularly on the tasks of segmentation and classification. In order to validate the contribution of 3D data to lesion identification, we compare the segmentations resulting from various combinations of images cues (e.g., colour, depth and texture) embedded in a region-based level set segmentation method. The experiments indicate that depth is complementary to colour. Adding the 3D information reduces the error rate from 7:8% to 6:6%. For the purpose of evaluating the segmentation results, we propose a novel ground truth estimation approach that incorporates a prior pattern analysis of a set of manual segmentations. The experiments on both synthetic and real data show that this method performs favourably compared to the state of the art approach STAPLE [1] on ground truth estimation. Finally, we explore the usefulness of 3D information to non-melanoma lesion diagnosis by tests on both human and computer based classifications of five lesion types. The results provide evidence for the benefit of the additional 3D information, i.e., adding the 3D-based features gives a significantly improved classification rate of 80:7% compared to only using colour features (75:3%). The three main contributions of the thesis are improved methods for lesion segmentation, non-melanoma lesion classification and lesion boundary ground-truth estimation.

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25

Dörr, Wolfgang. "Skin and Other Reactions to Radiotherapy – Clinical Presentation and Radiobiology of Skin Reactions". Karger, 2006. https://tud.qucosa.de/id/qucosa%3A27555.

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26

Bent, Julian, Joanna Lee e Tim Benson. "A T 2 D TDNMR study of skin". Diffusion fundamentals 14 (2010) 9, S. 1-5, 2010. https://ul.qucosa.de/id/qucosa%3A13859.

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T2D TDNMR data is used to improve the assignment of the location of water in in-vitro pig skin. Whilst the corresponding 1d experiments report broad distributions of T2 and D respectively, two water components are resolved in the T2D data and are assigned as intraand extra-cellular water by considering the peak intensities in; whole defatted skin, a dermatomed slice of the top 0.4mm (mostly epidermis) and the remaining sub layer (dermis). The relative proportion of fast relaxing/fast diffusing water is largest in the epidermis section (which has a close packed cellular structure) so is assigned as intra-cellular water. Whilst there is more slowly relaxing/slowly diffusing water in the dermis section (which has fewer cells within a collagen network) so this is assigned as extra-cellular water. The observation that intra-cellular water relaxes fastest, suggests that the skin cells contain more exchangeable species, through which the water can relax, than the extra-cellular network. This assignment is supported when resolution is lost on repeated freezing, i.e. the cell walls are broken. Resolution is also lost on increasing the diffusion time from 50 to 100 and 150ms. This is likely partly due to relaxation but also due to diffusion through the cell membranes during the experiment and gives a measure of the cell wall permeability.

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27

Diaz-Ayil, Gilberto. "Spectroscopie optique multi-modalités in vivo : instrumentation, extraction et classification diagnostique de tissus sains et hyperplasiques cutanés". Thesis, Vandoeuvre-les-Nancy, INPL, 2009. http://www.theses.fr/2009INPL085N/document.

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L’incidence des cancers cutanés est en constante progression. Leur diagnostic précoce et leur caractérisation in vivo constituent donc un enjeu important. Une approche multimodale et non invasive en spectroscopie fibrée résolue spatialement a été implémentée. L’instrumentation développée permet des mesures co-localisées en multiple excitation d’AutoFluorescence (AF, 7 pics entre 360 et 430 nm) et en Réflectance Diffuse (RD, 390 à 720 nm) résolues spatialement à 5 distances inter-fibres (entre 271 et 1341 µm). Le protocole expérimental a porté sur les stades précoces de cancers cutanés UV-induits sur un modèle pré-clinique. L’analyse histopathologique a permis de définir 4 classes de référence de tissus cutanés : Sain (S), Hyperplasie Compensatoire (HC), Hyperplasie Atypique (HA) et Dysplasie (D), menant à 6 combinaisons de paires histologiques à discriminer. Suite au prétraitement des spectres bruts acquis, puis à l’extraction, la sélection et la réduction de jeux de caractéristiques spectroscopiques, les performances de trois algorithmes de classification supervisée ont été comparées : k-Plus Proches Voisins, Analyse Discriminante Linéaire et Machine à Vecteur de Support. Différentes modalités ont également été évaluées : mono-excitation d’AF seule, Matrices d’Excitation-Emission en AF seules (EEMs), RD seule, couplage EEMs – RD et couplage EEMs – RD résolue spatialement. L’efficacité finale de notre méthode diagnostique a été évaluée en termes de sensibilité (Se) et de spécificité (Sp). Les meilleures résultats obtenus sont : Se et Sp ≈ 100% pour discriminer HC vs autres ; Sp ≈ 100% et Se > 95% pour discriminer S vs HA ou D ; Sp ≈ 74% et Se ≈ 63% pour HA vs D
The incidence of skin cancers is steadily increasing. Their in vivo early diagnosis and characterization is an important issue. An approach noninvasive: the spatially resolved multi-modality spectroscopy has been implemented. The instrumentation developed allows to co-localized measures in multiple AutoFluorescence excitation (AF, 7 peaks between 360 and 430 nm) and Diffuse Reflectance (DR, 390 to 720 nm) spatially resolved at 5 inter-fiber distances (between 271 and 1341 μm). The experimental protocol was focused on the early stages of skin cancer UV-induced in a preclinical model. Four reference classes were defined based on the histopathological analysis of the skin samples: Healthy (H), Compensatory Hyperplasia (CH), Atypical Hyperplasia (AH) and Dysplasia (D), leading to 6 combinations of class pairs to be discriminated. After preprocessing of the raw spectra, extraction, selection and reduction of the most discriminative spectroscopic data set were performed. Then, the efficacy of three supervised classification algorithms was compared: k-Nearest Neighbors, Linear Discriminant Analysis and Support Vector Machine. The contribution of the different modalities was also evaluated: single AF excitation alone, Excitation-Emission Matrices AF (EEMs) alone, DR alone, coupling of EEMs and RD, coupling of EEMs and DR with spatial resolution. The final efficiency of our diagnostic method was evaluated in terms of sensitivity (Se) and specificity (Sp). The best results obtained are: Se and Sp ≈ 100% for discriminating CH vs others; Sp ≈ 100% and Se> 95% for discriminating AH or D vs H; Sp ≈ 74% and Se ≈ 63% to discriminate AH vs D

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28

Sharif, Monier A. Mohamed [Verfasser]. "Epidemiology of skin tumor entities according to the new WHO classification in dogs and cats / eingereicht von Monier A. Mohamed Sharif". Wettenberg : VVB Laufersweiler, 2006. http://d-nb.info/981573649/34.

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29

Aizikovitsh, Einav, e Miriam Amit. "An innovative model for developing critical thinking skills throughmathematical education". Proceedings of the tenth International Conference Models in Developing Mathematics Education. - Dresden : Hochschule für Technik und Wirtschaft, 2009. - S. 19 - 22, 2012. https://slub.qucosa.de/id/qucosa%3A1665.

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In a challenging and constantly changing world, students are required to develop advanced thinking skills such as critical systematic thinking, decision making and problem solving. This challenge requires developing critical thinking abilities which are essential in unfamiliar situations. A central component in current reforms in mathematics and science studies worldwide is the transition from the traditional dominant instruction which focuses on algorithmic cognitive skills towards higher order cognitive skills. The transition includes, a component of scientific inquiry, learning science from the student''s personal, environmental and social contexts and the integration of critical thinking. The planning and implementation of learning strategies that encourage first order thinking among students is not a simple task. In an attempt to put the importance of this transition in mathematical education to a test, we propose a new method for mathematical instruction based on the infusion approach put forward by Swartz in 1992. In fact, the model is derived from two additional theories., that of Ennis (1989) and of Libermann and Tversky (2001). Union of the two latter is suggested by the infusion theory. The model consists of a learning unit (30h hours) that focuses primarily on statistics every day life situations, and implemented in an interactive and supportive environment. It was applied to mathematically gifted youth of the Kidumatica project at Ben Gurion University. Among the instructed subjects were bidimensional charts, Bayes law and conditional probability; Critical thinking skills such as raising questions, seeking for alternatives and doubting were evaluated. We used Cornell tests (Ennis 1985) to confirm that our students developed critical thinking skills.

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30

Stefanidis, Angelos. "Undergraduate information systems in the UK : analysing curriculum skills and industry needs". Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/14267.

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In recent years there have been repeated calls for universities to better equip students with skills which are relevant to business and industry. The field of Information Systems (IS), along with the wider discipline of computing, has often been described as outdated, slow to adopt new technologies and unable to keep up with the fast pace of change of the real world . Exacerbating the issue of academic relevance in relation to industry needs, universities around the world have experienced a growing disinterest in the study of IS and computing, resulting in worryingly low levels of new graduates who do not meet industry demands. To understand the contentious relationship between academia and business in relation to IS, the research presented in this thesis investigates the current IS undergraduate provision in the UK and its alignment with the skill requirements of the IS industry. This is achieved through a two-stage approach of examining the position and expectations of each stakeholder, followed by the development of a method to facilitate the alignment of their inter-related needs. As part of the first stage, the investigation into the academic stakeholder undertakes a holistic analysis of IS curriculum to quantify its content. This leads to the identification of original Career Tracks which specify the IS careers promoted by the curriculum. The second stage involves the investigation of the business stakeholder measuring the careers in demand and the skills that support them. The resulting findings from these investigations show that it is possible to determine the skills required by IS graduates in the UK to meet the demands of industry. This is achieved through the use of a newly developed IS Course Survey Framework that enables the configuration of IS courses to align to specific career tracks, thus mapping directly to the needs of industry as expressed through their job requirements and associated skills demand.

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31

Naffa, Rafea, C. Maidment, G. Holmes e G. Norris. "Strong skin, not always thick - 30: Comparative structural and molecular analysis of deer skin and cow hide". Verein für Gerberei-Chemie und -Technik e. V, 2019. https://slub.qucosa.de/id/qucosa%3A34089.

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Content: A comprehensive analysis of the molecular and structural components of deer skin and cow hide was undertaken. These skins known to be strong, however they derive their strength from diﬀerent combinations of molecular and structural properties. Firstly, the physical properties of deer skin and cow hide including the tensile strength, tear strength and denaturation temperature were measured. Secondly, the structure of the collagen ﬁbrils and glycosaminoglycans was investigated using transmission electron microscopy (TEM), and small angle X-ray scattering (SAXS). Finally, the chemical composition of deer skin and cow hide such as amino acids, crosslinks and glycosaminoglycans were analysed. Our results showed that physical properties of deer skin and cow hide are derived from diﬀerent combinations of several chemical components resulting in diﬀerent architecture. It was found that the large and “wavy” collagen ﬁbres in deer skin made up of collagen ﬁbrils with small diameters. Additionally, deer skin ﬁbrils appeared to be linked by regular arrays of ﬁlaments of large glycosaminoglycans that are distributed uniformly. Deer skin contained higher proportion of trivalent collagen crosslinks. In contrast, the collagen ﬁbrils in cow hide were large, contained a diverse glycosaminoglycan distribution and a higher proportion of tetravalent collagen crosslinks, resulting in straight collagen ﬁbres. This study suggests that although deer skin and cow hide are both strong, they have diﬀerent structural and molecular features. Take-Away: Deer skin and cow hide have different structural and molecular make up which are reflected in their physical properties particularly strength. Glycosaminoglycans are important for the organisation of collagen fibrils in deer skin and cow hide. Deer skin and cow hide contain different ratios of collagen natural crosslinks which are essential collagen stability.

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Galarza, Betina, M. L. Garro, N. Ferreri, L. Elíades e R. Hours. "A new fungal isolates applicated to bovine skin in beamhouse processes - 307". Verein für Gerberei-Chemie und -Technik e. V, 2019. https://slub.qucosa.de/id/qucosa%3A34210.

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Content: Beamhouse area is an important step in leather technology, either in the final quality of the leather or in the contribution to the contamination of effluents. In unhairing process, the use of enzymes as sulphide assistants can reduce sulfhidric gas emissions to reach permitted levels for health. The characterization of enzymatic extracts allows controlling the proteolysis mechanism so that its action does not attack the reticular structure. A new fungal enzyme extracts were applied on submerged bovine skin in the soaking and unhairing steps. Fungal strains were isolated from alkaline soils of coast of Buenos Aires province and enzymatic extracts (EE) were obtained by submerged culture with bovine hair waste from hair-saving unhairing process as inducer in the production of keratinolytic enzymes. This activity was determined by quantitative test and the most productive strains were selected: Clonostachys rosea (CR), Emericellopsis minima (EM), Paecilomyces lilacinus (PL), Penicillium sp (Psp), Fusarium oxysporum (FO), Acremonium sp (A) and an unidentified filamentous fungus strain with sterile yellow mycelium (SYM). EE were tested at laboratory scale on submerged bovine skin with biocide 0,2% w/w wet skin, anionic 0,1% and non-ionic 0,5% tensioactives in soaking and unhairing respectively and incubated 48 h at 37°C in shaking thermostatic bath. Controls were tested in the same conditions without EE. Morphological changes in the skin were observed by scanning electron microscopy (SEM). Pieces of bovine skin were fixed, post-fixed in formaldehyde 4% and dehydrated in alcohol solutions, treated by critical point drying, metalized and analyzed in SEM. It was observed with FO, EM and A extracts empty hair follicles, absence of epidermis, papillary layer of dermis exposed, hairs enclosed by detached hair follicle sheaths and collagen fibers without characteristic patterns. With PL and SYM EE some hairs were detached while Psp and CR EE did not produce changes. In control samples epidermis and hair without modification were observed. In the quantitative test, keratinolytic activities increased in the following order: A

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33

Peters, Karsten, Johannes Quaas e Nicolas Bellouin. "Effects of absorbing aerosols in cloudy skies: a satellite study over the Atlantic Ocean". Copernicus Publication, 2011. https://ul.qucosa.de/id/qucosa%3A12777.

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We present a method for deriving the radiative effects of absorbing aerosols in cloudy scenes from satellite retrievals only. We use data of 2005–2007 from various passive sensors aboard satellites of the “A-Train” constellation. The study area is restricted to the tropical- and subtropical Atlantic Ocean. To identify the dependence of the local planetary albedo in cloudy scenes on cloud liquid water path and aerosol optical depth (AOD), we perform a multiple linear regression. The OMI UV-Aerosolindex serves as an indicator for absorbing-aerosol presence. In our method, the aerosol influences the local planetary albedo through direct- (scattering and absorption) and indirect (Twomey) aerosol effects. We find an increase of the local planetary albedo (LPA) with increasing AOD of mostly scattering aerosol and a decrease of the LPA with increasing AOD of mostly absorbing aerosol. These results allow us to derive the direct aerosol effect of absorbing aerosols in cloudy scenes, with the effect of cloudy-scene aerosol absorption in the tropical- and subtropical Atlantic contributing (+21.2±11.1)×10−3 Wm−2 to the global top of the atmosphere radiative forcing.

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Cavalcanti, Pablo Gautério. "Automated prescreening of melanocytic skin lesions using standard camera images". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/72926.

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Melanoma é um tipo maligno de lesão de pele pigmentada, e atualmente está entre os tipos de câncer existentes mais perigosos. Entretanto, diferenciar casos malignos de benignos é uma tarefa difícil mesmo para experientes especialistas, e um sistema de diagnóstico auxiliado por computador pode ser uma ferramenta bastante útil. Normalmente, este sistema inicia por um pré-processamento da imagem, isto é, remoção de artefatos indesejados, como pelos, sardas ou efeitos de sombreamento. A seguir, o sistema executa uma etapa de segmentação, identificando as bordas da lesão. Por fim, baseando-se na área da imagem identificada como lesão, diversas feições são computadas e uma classificação é gerada. Neste tese, apresentada na forma de uma coleção de artigos publicados, nós apresentamos técnicas para automaticamente executar todos estes passos, resultando em um pré-diagnóstico para uma lesão de pele pigmentada baseado apenas em uma imagem convencional (uma simples fotografia). Nós testamos nossos métodos em bases de imagens públicas e atingimos melhores resultados de segmentação e classificação que os demais métodos presentes na literatura.
Melanoma is a type of malignant pigmented skin lesion, and currently is among the most dangerous existing cancers. However, differentiating malignant and benign cases is a hard task even for experienced specialists, and a computer-aided diagnosis system can be an useful tool. Usually, the system starts by pre-processing the image, i.e. removing undesired artifacts such as hair, freckles or shading effects. Next, the system performs a segmentation step to identify the lesion boundaries. Finally, based on the image area identified as lesion, several features are computed and a classification is provided. In this Thesis, presented as a collection of published papers, we detail approaches to automatically execute all these steps, resulting in a pre-diagnosis for a pigmented skin lesion based only in a standard camera image (i.e. a simple color photograph). We tested our methods on publicly available datasets and achieved better segmentation and classification results than methods previously proposed in the literature.

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Eckhardt, Jennifer. "Vermittlung von digitalen Fähigkeiten in außerschulischen Lernorten. Das europäische Kooperationsprojekt Codemob an der Schnittstelle zwischen Forschung und Praxis". TUDpress, 2017. https://tud.qucosa.de/id/qucosa%3A30898.

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Der Beitrag gibt einen Einblick in die zweijährige Arbeit des europäischen Kooperationsprojektes Codemob (Laufzeit Oktober 2015 – Oktober 2017), das sich der Entwicklung eines Kurrikulums für Vermittler digitaler Kompetenzen in Internet-Erfahrungsorten und deren Adressat_innen widmet. Mit einem multidisziplinären Team aus fünf Ländern wurden, gefördert durch das EU-Rahmenprogramm Erasmus+, zwei Module ausgearbeitet, die Grundkenntnisse in Programmiersprachen (Coding) und in der Nutzung mobiler Endgeräte (Mobile) vermitteln. Die Kurse gehören zu einem Gesamtkurrikulum aus 13 Modulen, die unterschiedliche digitale Themen behandeln (z.B. Bildbearbeitung, Netzsicherheit). Der Beitrag fokussiert die Kooperationswege innerhalb des Projektteams zwischen Anwender_innen, Forschenden und intermediären Organisationen.

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36

Hashem, M. A., M. Hasan, M. A. Momen e S. Payel. "Minus salt goat skin preservation - 43: Extreme chloride reduction in tannery wastewater". Verein für Gerberei-Chemie und -Technik e. V, 2019. https://slub.qucosa.de/id/qucosa%3A34143.

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Content: Animal skins, a byproduct of the meat industry is the basic raw materials for the tanning industry. Just after flaying, animal skins have to preserve protecting it from microbiological destruction. Globally, sodium chloride is mostly used as popular preserving agents for the animal skins. It preserves the skin by its dehydrating ability. Nevertheless, sodium chloride is cost-effective, available, and easy to apply but the method suffers greatly in terms of environmental context. To reduce the pollution load, especially chloride in soaking operation several works have been carried out to preserve animal skins with various agents. This study is intended to preserve the goat skin with Sphagneticola trilobata leaf paste without sodium chloride for reducing the chloride in the soaking liquor. The plant has antimicrobial activity, widely distributed tropical and subtropical regions. The anticipated preservation method was assessed monitoring different parameters e.g., shrinkage temperature, hair slip, putrefaction, odour, moisture content, extractable nitrogen, and bacterial count on fresh (raw), 1st, 4th, 7th, 14th, 21st and 28th day in comparison to the conventional wet salting method. The physical properties of the processed leathers e.g., tensile strength, percentage of elongation, and ball burst of the crust leathers were fulfilled the required values. The chemical parameters like chloride, total dissolved solids (TDS), biochemical oxygen demand (BOD), and chemical oxygen demand (COD) of soaking liquor were investigated. The proposed preservation method was reduced pollution loads: chloride, TDS, BOD, and COD in soaking operation by 98.04%, 92.9%, 90.2% and 85.5%, respectively. The scanning electron microscope (SEM) photographs of both the present and conventional preservation methods processed crust leathers revealed similar texture and quality to each other. The anticipated preservation method could be a sustainable option to preserve goat skin, which could reduce the pollution loads during leather processing. Take-Away: 1. Sphagneticola trilobata leaf paste preserved goat skin up to 28 days 2. Reduction of chloride and TDS were 98.04% and 92.9% in soaking liquor 3. Lessening of BOD and COD were 90.2% and 85.5% in soaking liquor

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Ben, Amor Heni. "Imitation Learning of Motor Skills for Synthetic Humanoids". Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2010. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-62877.

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This thesis addresses the question of how to teach dynamic motor skills to synthetic humanoids. A general approach based on imitation learning is presented and evaluated on a number of synthetic humanoids, as well as a number of different motor skills. The approach allows for intuitive and natural specification of motor skills without the need for expert knowledge. Using this approach we show that various important problems in robotics and computer animation can be tackled, including the synthesis of natural grasping, the synthesis of locomotion behavior or the physical interaction between humans and robots.

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38

Ghouse, Shanawaz Mohammed. "Role of Mast cells in HPV-induced skin cancer". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-229004.

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Mast cells (MCs) are long-lived immune cells, which were reported to play an important role in initiating innate and adaptive immune responses against various infections. MCs accumulate in high numbers in the stroma and at the invasion front of various human cancers, suggesting a possible contribution by MCs to tumour growth. Experimental studies using crosses of MC-deficient Kit-mutant mouse strains with mouse models of epithelial cancers have provided evidence for important MC tumour-promoting functions. However, the complex alterations of the immune system that characterize Kit-mutant mice in addition to their MC deficiency, limit the interpretation of these findings. Numerous key observations made in Kit mutant mice were not reproduced in novel, Kit-independent mouse models of MC deficiency. Thus, the impact of MCs on tumour biology remains unclear. The aim of this study is to clarify the contribution of MCs to the biology of Human papilloma virus (HPV)-induced skin cancer in a Kit-independent mouse model of MC deficiency. In K14-HPV16 transgenic mice, HPV oncogenes are constitutively expressed in the epidermis resulting in epidermal hyperplasia with 100% penetrance and squamous cell carcinoma in about 50% of the animals. A cross to a Kit-mutant line suggested that MCs are important tumour promoters in this model. We crossed K14-HPV16 mice to M5Cre R-DTA line, in which MCs are constitutively depleted with high efficiency and selectivity. Unexpectedly, the loss of MCs neither affected keratinocyte proliferation indices nor altered keratinocyte apoptosis at any stage of HPV-induced neoplasia. Furthermore, the loss of MCs did not result in any detectable changes in composition and gene expression of the inflammatory hematopoietic cell infiltrate in the tumour stroma. This shows that, contrary to current belief, MCs have no important function in orchestrating the tumour micro milieu. In keeping with this finding, MC deficiency resulted in no detectable difference in the incidence growth or grading of SSC in K14-HPV16 transgenic mice. Collectively, these results show that, despite their high density in HPV-induced neoplasia, MC have no role in cancerogenesis or neoplastic progression in the K14-HPV16 mouse model. Our findings also emphasize the importance of novel Kitindependent mouse models in the investigation of MC in vivo functions.

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Triyono, Moch Bruri, Thomas Köhler e Lilis Trianingsih. "Technical working skills of vocational high school students at the interface between digital workplaces and school. An empirical study about construction engineering drawings in Indonesia". TUDpress, 2018. https://tud.qucosa.de/id/qucosa%3A33835.

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Recent studies report about the need for and difficulties in measuring technical working skills among vocational high school students worldwide (Mabed & Köhler, 2018). Often the discussion is linked to the question of skills versus competencies, not only in the context of new digitized forms of measurement. Furthermore, a growing number of completely new or updated measurement procedures is about to reach the TVET sector in the context of the digitization of TEL (Köhler & Drummer, 2018; Hariyanto & Köhler, 2017). This study aimed at investigating the differences of the technical skills of vocational high school students majoring in construction drawings engineering in industrial working practices. As an empirical approach for their evaluation study authors used a discrepancy evaluation model. The population of this study consisted of 195 students in Yogyakarta and Sleman, Indonesia. A proportional random sampling was used to select 124 students from the population with both, the industrial work and the students becoming the sources of the information. The data analysis process was done using descriptive analysis and Wilcoxon matched pairs test analysis to describe and find the gap/discrepancy of students’ technical skills based on the predetermined standard. The results of the study show that the technical skills of vocational high school students in their industrial working practices are categorized as good with a low discrepancy based on the industrial assessment, and even better based on the students’ self-assessment. Yet there is a significant difference of technical skills among the vocational high school students in their industrial working practices based on the industrial work and students’ assessment with a significant value of 0.000 < 0,05.

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40

Kutsche, Kerstin, Walter Werner, Oliver Bartsch, der Wense Axel von, Peter Meinecke e Andreas Gal. "Microphthalmia with linear skin defects syndrome (MLS): a male with a mosaic paracentric inversion of Xp". Karger, 2002. https://tud.qucosa.de/id/qucosa%3A27747.

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The microphthalmia with linear skin defects syndrome (MLS) is an X-linked dominant disorder with male lethality. In the majority of the patients reported, the MLS syndrome is caused by segmental monosomy of the Xp22.3 region. To date, five male patients with MLS and 46,XX karyotype (“XX males”) have been described. Here we report on the first male case with MLS and an XY complement. The patient showed agenesis of the corpus callosum, histiocytoid cardiomyopathy, and lactic acidosis but no microphthalmia, and carried a mosaic subtle inversion of the short arm of the X chromosome in 15% of his peripheral blood lymphocytes, 46,Y,inv(X)(p22.13∼22.2p22.32∼22.33)[49]/46,XY[271]. By fluorescence in situ hybridization (FISH), we showed that YAC 225H10 spans the breakpoint in Xp22.3. End-sequencing and database analysis revealed a YAC insert of at least 416 kb containing the genes HCCS and AMELX, and exons 2–16 of ARHGAP6. Molecular cytogenetic data suggest that the Xp22.3 inversion breakpoint is located in intron 1 of ARHGAP6, the gene encoding the Rho GTPase activating protein 6. Future molecular studies in karyotypically normal female MLS patients to detect submicroscopic rearrangements including the ARHGAP6 gene as well as mutation screening of ARHGAP6 in patients with no obvious chromosomal rearrangements will clarify the role of this gene in MLS syndrome.
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

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Nguyen, Truong Giang, Thi Nga Nguyen, Thi Tuyet Vu e Thi Ngoan Bui. "Survey on the effects of pre-treatment process with acid on the capacity of gelatin extraction from pork skin". Technische Universität Dresden, 2016. https://tud.qucosa.de/id/qucosa%3A32630.

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Gelatin is increasingly becoming an important raw material in many different fields. The pretreatment stage of the production of gelatin from pork skin plays an important role, it has big effect on the quality of obtained products. A survey on 5 types of acid HCl, H2SO4, H3PO4, CH3COOH, Citric was conducted. It showed that the influence of these types of acid on the pretreatment process was different. Acetic acid made the best result with the protein after extraction reaching 54.88 mg/ml, the product bloom reached 223. The most appropriate proportion of acetic acid was 3%. A survey on the effect of soaking time on the capacity of extraction was conducted. The result showed that the 16-hour extraction brought the best result reaching 56.16 mg/ml, the product bloom reached 245. The most suitable proportion of soaking pork skin:acid was 1:2. The most appropriate temperature of acid immersion was 15°C, at which the protein after extraction reached 68.39 mg/ml, the product bloom reached 299, the viscosity reached 23 mPas.
Gelatin ngày càng trở thành nguồn nguyên liệu quan trọng trong nhiều lĩnh vực khác nhau. Giai đoạn tiền xử lý của việc sản xuất gelatin từ bì lợn đóng vai trò quan trọng và có ảnh hưởng lớn tới chất lượng sản phẩm thu được. Khảo sát 5 loại axit: HCl, H2SO4, H3PO4, CH3COOH, Citric, thấy rằng ảnh hưởng của các loại axit này trong quá trình tiền xử lý là khác nhau. Axit axetic cho kết quả tốt nhất với hàm lượng protein sau trích ly đạt 54,88 mg/ml, độ bloom sản phẩm đạt 223. Nồng độ thích hợp nhất của axit axetic là 3%. Khảo sát ảnh hưởng của thời gian ngâm đến khả năng trích ly thấy rằng 16 giờ cho kết quả tốt nhất đạt 56,16 mg/ml, độ bloom sản phẩm đạt 245. Tỷ lệ ngâm bì lợn: axit thích hợp nhất là 1:2. Nhiệt độ ngâm axit thích hợp nhất là 15oC, tại đó hàm lượng protein sau trích ly đạt 68,39 mg/ml, độ bloom sản phẩm đạt 299, độ nhớt đạt 23 mPs.

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Meissner, Hartwig, e Annabella Diephaus. "Paper&Pencil Skills in the 21st Century, a Dichotomy?" Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-80642.

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There is a worldwide development, better to say a non-development: We teach paper & pencil skills in primary schools almost like we did 30 or 50 or 100 years ago. Till today the primary school teachers spend up to more than 100 hours in the class room to teach and to train old fashioned algorithms though in daily life situations and for business purposes everybody uses a calculator. Why do we waste so much time of our children to teach them things which later on they will not need? We see an emotional dichotomy. Despite the research results from many research projects in many countries there still is the fear that the use of calculators in primary grades will harm mental arithmetic and estimation skills. To explain and to overcome that fear we will reflect the nature of number sense and of paper&pencil skills more carefully. We realize that the development of number sense is an intuitive and unconscious mental process while the ability to get an exact calculation result is trained logically and consciously. To overcome the above dichotomy we must solve the hidden dichotomy number sense versus precise calculation result. We need a new balance. Different types of examples will be given how we can further the development of number sense in a technology dominated curriculum.

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43

Golightly, Christopher Robert. "Engineering properties of carbonate sands : the geological origins, classification, engineering, shear and triaxial stress path properties of four carbonate sands. The analysis of the transfer function for pile skin friction". Thesis, University of Bradford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285066.

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44

Maurer, Patrick, Antonia Christine Raida, Ernst Lücker e Sander Münster. "Visual media as a tool to acquire soft skills — cross-disciplinary teaching-learning project SUFUvet". TUDpress, 2016. https://tud.qucosa.de/id/qucosa%3A33985.

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Purpose – SUFUvet is a cross-disciplinary teaching-learning project designed to adapt students’ soft skills and track usability and the concrete surplus value of work techniques in the field of visual media design. Design/methodology/approach – For SUFUvet, a collaboration between the Institute of Food Hygiene/University of Leipzig and the Media Center/Technische Universität Dresden was initiated. Bachelor students of media informatics generate 3D visualisations in the framework of SCRUM: Undergraduate veterinary students issue instructions in order to create an e-learning class. During the project, questionnaires, group discussions, and feedback methods are used to detect changes in selected soft skills. Originality/value – This design is meant to increase knowledge and employability by adapting student’s media, communication, and project management competences. Using SCRUM appears to be a new approach, not only in the field of programming, but for media production as well. Additionally, it offers an interdisciplinary work environment, which is rare but considered fruitful within university studies. Practical implications – The outcomes of the application are a 3D-visualised meat inspection e-learning class for veterinary students plus a documentation of SCRUM as a framework for visual media design. It is seen as an experiment for future applications in a variety of cross-disciplinary learning and media design cases.

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45

Swersky, Liz. "Developing Skills for Successful Learning". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-83124.

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Julian, Pauline. "Méthodes variationnelles pour la segmentation avec application à la réalité augmentée". Phd thesis, Toulouse, INPT, 2012. http://oatao.univ-toulouse.fr/17822/7/Julian_P.pdf.

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Dans cette thèse, nous nous intéressons au problème de la segmentation de portraits numériques. Nous appelons portrait numérique la photographie d’une personne avec un cadre allant grossièrement du gros plan au plan poitrine. Le problème abordé dans ce travail est un cas spécifique de la segmentation d’images où il s’agit notamment de définir précisément la frontière de la région « cheveux ». Ce problème est par essence très délicat car les attributs de la région « cheveux » (géométrie, couleur, texture) présentent une grande variabilité à la fois entre les personnes et au sein de la région. Notre cadre applicatif est un système d’« essayage virtuel » de lunettes à destination du grand public, il n’est pas possible de contrôler les conditions de prise de vue comme l’éclairage de la scène ou la résolution des images, ce qui accroît encore la diculté du problème. L’approche proposée pour la segmentation de portraits numériques est une approche du plus grossier au plus fin procédant par étapes successives. Nous formulons le problème comme celui d’une segmentation multi-régions, en introduisant comme « régions secondaires », les régions adjacentes à la région « cheveux » , c.-à-d. les régions « peau » et « fond ». La méthode est fondée sur l’apparence (appearance-based method) et a comme spécificité le fait de déterminer les descripteurs de régions les plus adaptés à partir d’une base d’images d’apprentissage et d’outils statistiques. À la première étape de la méthode, nous utilisons l’information contextuelle d’un portrait numérique — connaissances a priori sur les relations spatiales entre régions— pour obtenir des échantillons des régions « cheveux », « peau » et « fond ». L’intérêt d’une approche fondée sur l’apparence est de pouvoir s’adapter à la fois aux conditions de prises de vue ainsi qu’aux attributs de chaque régions. Au cours de cette étape, nous privilégions les modèles de forme polygonaux couplés aux contours actifs pour assurer la robustesse du modèle. Lors de la seconde étape, à partir des échantillons détectés à l’étape précédente, nous introduisons un descripteur prenant en compte l’information de couleur et de texture. Nous proposons une segmentation grossière par classification en nous appuyant à nouveau sur l’information contextuelle : locale d’une part grâce aux champs de Markov, globale d’autre part grâce à un modèle a priori de segmentation obtenu par apprentissage qui permet de rendre les résultats plus robustes. La troisième étape ane les résultats en définissant la frontière des « cheveux » comme une région de transition. Cette dernière contient les pixels dont l’apparence provient du mélange de contributions de deux régions (« cheveux »et « peau » ou «fond »). Ces deux régions de transition sont post-traitées par un algorithme de «démélange » (digital matting) pour estimer les coecients de transparence entre « cheveux » et « peau », et entre « cheveux » et « fond ». À l’issue de ces trois étapes, nous obtenons une segmentation précise d’un portrait numérique en trois « calques », contenant en chaque pixel l’information de transparence entre les régions « cheveux », « peau » et « fond ». Les résultats obtenus sur une base d’images de portraits numériques ont mis en évidence les bonnes performances de notre méthode.

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Ashrafi, Parivash. "Predicting the absorption rate of chemicals through mammalian skin using machine learning algorithms". Thesis, University of Hertfordshire, 2016. http://hdl.handle.net/2299/17310.

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Machine learning (ML) methods have been applied to the analysis of a range of biological systems. This thesis evaluates the application of these methods to the problem domain of skin permeability. ML methods offer great potential in both predictive ability and their ability to provide mechanistic insight to, in this case, the phenomena of skin permeation. Historically, refining mathematical models used to predict percutaneous drug absorption has been thought of as a key factor in this field. Quantitative Structure-Activity Relationships (QSARs) models are used extensively for this purpose. However, advanced ML methods successfully outperform the traditional linear QSAR models. In this thesis, the application of ML methods to percutaneous absorption are investigated and evaluated. The major approach used in this thesis is Gaussian process (GP) regression method. This research seeks to enhance the prediction performance by using local non-linear models obtained from applying clustering algorithms. In addition, to increase the model's quality, a kernel is generated based on both numerical chemical variables and categorical experimental descriptors. Monte Carlo algorithm is also employed to generate reliable models from variable data which is inevitable in biological experiments. The datasets used for this study are small and it may raise the over-fitting/under-fitting problem. In this research I attempt to find optimal values of skin permeability using GP optimisation algorithms within small datasets. Although these methods are applied here to the field of percutaneous absorption, it may be applied more broadly to any biological system.

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Benešová, Daniela, Uwe Lange, Janine Oelze, Václav Salcman, Henry Schulz, Simone Schuster e Petr Valach. "Přeshraniční srovnávací analýza motorických schopností dětí mladšího školního věku - pilotní studie". Technische Universität Chemnitz, 2014. https://monarch.qucosa.de/id/qucosa%3A19147.

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Vzrůstající nedostatek pohybu dětí a mladistvých v průmyslových státech se v minulých desetiletích rozvinul ve zdravotně-politický problém. V souladu s touto problematikou zároveň klesá i úroveň motorických schopností a dovedností, což představuje citelné omezení dětského vývoje, fyzické i psychické komponenty. Důsledkem jsou rostoucí náklady na zdravotní péči, které posléze výrazně zatěžují zdravotnictví v jednotlivých zemích. Cílem vědeckých týmů Západočeské Univerzity v Plzni a Technické Univerzity Chemnitz je v rámci pilotní studie pod názvem „Přeshraniční srovnávací analýza motorických schopností dětí mladšího školního věku“ stanovit a porovnat aktuální zdravotní situaci školáků v České republice a Německu.
Der gestiegene Bewegungsmangel der Kinder und Jugendlichen in den Industriestaaten hat sich in den vergangenen Jahrzehnten zu einem gesundheitspolitischen Problem entwickelt. Das darüber hinaus sinkende Niveau motorischer Fähigkeiten und Fertigkeiten zieht Beeinträchtigungen der kindlichen Entwicklung auf physischer und psychischer Ebene mit entsprechenden Folgekosten für die Gesundheitssysteme der Länder nach sich. Die Wissenschaftler der Westböhmischen Universität Pilsen und der Technischen Universität Chemnitz haben sich aus diesem Grund zum Ziel gesetzt, in der Pilotstudie „Grenzüberschreitende Vergleichsanalyse der motorischen Fähigkeiten von Kindern des jüngeren Schulalters“ die gesundheitliche Situation von Schulanfängern in der Tschechischen Republik und in Deutschland zu untersuchen und gegenüber zu stellen.
The increased sedentary lifestyle of children and adolescents in industrialized countries has evolved into a public health problem over the past decades. In addition, the declining level of motor abilities and skills draws impairment of children development on physical and psychological level, with appropriate follow-up costs for the health systems of countries. Scientists at the University of West Bohemia Pilsen and the Chemnitz University of Technology have for this reason the goal to investigate and to contrast the health situation of children starting school in the Czech Republic and in Germany with the pilot study "Cross-border comparative analysis of the motor skills of children of younger school age".

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49

Rall, Kathrin. "Untersuchungen zur Rolle von Vaspin in der Psoriasis". Doctoral thesis, Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-89762.

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Die Psoriasis ist eine meist schubweise verlaufende, chronisch-entzündliche Erkrankung der Haut. Sie ist genetisch determiniert und charakterisiert durch eine Dysregulation der Keratinozytenproliferation und der zellulären Immunabwehr. Patienten mit Psoriasis weisen meist noch weitere Begleiterkrankungen auf. So konnte in verschiedenen klinischen Studien ein Zusammenhang zwischen Psoriasis und Adipositas hergestellt werden. Die Zellen des weißen Fettgewebes sekretieren sowohl pro- als auch antiinflammatorische Mediatoren (Adipokine), die Einfluss auf verschiedene metabolische Prozesse und auch Entzündungsreaktionen nehmen können. In der vorliegenden Dissertation wurde ein möglicher Einfluss des Adipokins Vaspin auf die Pathogenese der Psoriasis untersucht. Literaturbekannte Daten belegen im Tiermodell eine antiinflammatorische Wirksamkeit von Vaspin. Obgleich der Pathomechanismus der Psoriasis bislang nicht vollständig aufgeklärt wurde, ist derzeit eine bedeutende Rolle von dendritischen Zellen unbestritten. Als antigenpräsentierende Zellen nehmen sie in der initialen Phase der Erkrankung Einfluss auf deren weiteren Verlauf. So lag ein Schwerpunkt der vorliegenden Arbeit darin, die Wirkung von Vaspin auf dendritische Zellen bezüglich der Expression von Oberflächenmarkern und der Sekretion von Zytokinen zu untersuchen. Weitere Versuche waren darauf ausgerichtet, die Serumkonzentrationen von Vaspin in Psoriatikern mit denen einer Referenzgruppe in Abhängigkeit des BMI zu vergleichen. Darüber hinaus wurde die Expression von Vaspin auf mRNA-Ebene unter Verwendung von Hautbioptaten aus psoriatrischen Läsionen und gesunden Kontrollen evaluiert. Unter Verwendung eines spezifischen Antikörpers gelang in der Immunhistochemie erstmals der Nachweis von Vaspin auf Proteinebene in histologischen Schnittpräparaten gesunder und psoriatrisch veränderter Haut.

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50

Ranner, Tamara, e Gabi Reinmann. "Videoreflexion und Wissenskooperation in der Fahrlehrerausbildung". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-76450.

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Videotechnologien werden in der Lehrerbildung häufig eingesetzt, um die Lehrkompetenz zu fördern. Auch in der Fahrlehrerausbildung werden sie schon lange genutzt, hauptsächlich jedoch als Demonstrationsmaterial in Präsenzsitzungen. Eine aktiv-konstruktive Bearbeitung der Videos mit Hilfe digitaler Technologien findet nicht statt. Mittels internetgestützter Videoreflexion wurde im Rahmen eines EU-Projektes versucht, die Lehrkompetenz angehender Fahrlehrer zu fördern. Dabei hat sich gezeigt, dass ein Austausch unter den Ausbildern darüber, wie sie Videotechnologien in der Fahrlehrerausbildung einsetzen, sehr wichtig ist, um Standards zu entwickeln. In der Praxis tauschen sich Ausbilder verschiedener Einrichtungen kaum untereinander aus. Ausgehend von den Erkenntnissen aus dem EU-Projekt beschreibt dieser Beitrag ein geplantes Vorhaben zum Aufbau einer Professional Community, in der Ausbilder gemeinsam Standards für eine videobasierte Lehrkompetenzförderung entwickeln sollen.

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