Information overload in structured data

Information overload refers to the difficulty of making decisions caused by too much information. In this dissertation, we address information overload problem in two separate structured domains, namely, graphs and text. Graph kernels have been proposed as an efficient and theoretically sound approach to compute graph similarity. They decompose graphs into certain sub-structures, such as subtrees, or subgraphs. However, existing graph kernels suffer from a few drawbacks. First, the dimension of the feature space associated with the kernel often grows exponentially as the complexity of sub-structures increase. One immediate consequence of this behavior is that small, non-informative, sub-structures occur more frequently and cause information overload. Second, as the number of features increase, we encounter sparsity: only a few informative sub-structures will co-occur in multiple graphs. In the first part of this dissertation, we propose to tackle the above problems by exploiting the dependency relationship among sub-structures. First, we propose a novel framework that learns the latent representations of sub-structures by leveraging recent advancements in deep learning. Second, we propose a general smoothing framework that takes structural similarity into account, inspired by state-of-the-art smoothing techniques used in natural language processing. Both the proposed frameworks are applicable to popular graph kernel families, and achieve significant performance improvements over state-of-the-art graph kernels. In the second part of this dissertation, we tackle information overload in text. We first focus on a popular social news aggregation website, Reddit, and design a submodular recommender system that tailors a personalized frontpage for individual users. Second, we propose a novel submodular framework to summarize videos, where both transcript and comments are available. Third, we demonstrate how to apply filtering techniques to select a small subset of informative features from virtual machine logs in order to predict resource usage

Naive Attempt of Quantum Mechanics: Axonal Membrane

Quantum mechanics -by using what we know about the system now- provides us information about the future of the system. Quantum physics and biology have been regarded as unrelated disciplines, describing nature at the inanimate micro level on the one hand and living species on the other hand. However, currently it is known that quantum mechanics is necessary in the description and understanding of natural phenomena. In fact, phenomena, which occur on a very small scale, cannot be explained outside the framework of quantum physics. It leads naturally to the question: Can quantum mechanics play a role in biology? In many ways it is clear that it already does.The concept of tunneling is as old as quantum mechanics. The electrons have a finite probability of tunneling through the insulator without having enough energy to mount it. Although quantum effects are subtle, quantum mechanical tunneling may be important in understanding many membrane processes. This paper is a naive attempt to understand the potassium current characteristics from the quantum mechanical point of view

Clinical features and prognostic significance of splenic involvement in sarcoidosis

Sarcoidosis is a systemic disease characterized by noncasefied granulomas in various organs. Incidence of splenic disease is variable and is reported to occur in 6.7 to 77 percent of the patients. Firm data establishing the clinical features and the association of splenic involvement with prognosis in sarcoidosis is scant. The aim of our study was to investigate the clinical features and the consequence of splenic involvement on the prognostic outcome of sarcoidosis patients. We evaluated the clinical and laboratory findings in 82 sarcoidosis patients. Forty-two patients with splenic involvement were compared to 48 sarcoidosis patients without splenic disease in regard to laboratory findings, endobronchial disease, extrapulmonary organ involvement, and prognosis. Lung biopsy sample was considered positive if it demonstrated noncaseating granulomas with negative fungal and mycobacterial cultures. Splenic sarcoidosis was identified by ultrasound or computed tomography and was designated as limited, diffuse or without splenic involvement. Extrapulmonary organ sarcoidosis was classified as extensive and limited. Endobronchial disease was categorized as limited or diffuse involvement. The most commonly comprised organ was lung in 95% of the cases followed by lymph nodes, skin, eye, spleen and liver in the order of frequency. Splenic disease was diffuse in 22 patients. Of these patients, 14 had extensive extrapulmonary organ involvement while 16 had diffuse endobronchial disease. There was no significant difference between the three groups for FEV1, FVC, TLC, DLCO/VA, serum and 24h urinary calcium levels. Serum ACE was higher in patients with diffuse splenic involvement (p<0.001). Incidence of persistent chronic disease was significantly higher (p<0.001) in patients with diffuse splenic sarcoidosis. Extensive extrapulmonary organ involvement and diffuse endobronchial disease were more common (p<0.001) in this group. Extensive extrapulmonary organ involvement and diffuse endobronchial disease were more frequent in patients with diffuse splenic sarcoidosis. Patients with diffuse splenic granulomas had a worse prognosis than the patients without splenic involvement or patients with limited splenic disease. Diffuse splenic involvement emerges to be a significant risk factor for persistent chronic sarcoidosis. Extensive granuloma burden in an organ may be the decisive clinical marker for the prognostic outcome of sarcoidosis patients.

Detection of α-Thalassemia by Using Multiplex Ligation-Dependent Probe Amplification as an Additional Method for Rare Mutations in Southern Turkey

α-thalassemia is the most common single gene disorder in the Cukurova Region in Turkey. It is therefore routinely screened, including premaritally, in our region. The heterogeneous molecular basis of the disease makes α-thalassemia mutation detection difficult and complex. Besides well established methods, multiplex ligation dependent probe amplification (MLPA) is known as an effective, simple and specific method for the detection and characterization of deletions and duplications. We employed MLPA testing to 30 patients with hematological parameters suggestive of α-thalassemia carrier status but was negative for α-thalassemia with conventional reverse dot blot hybridization (RDB). We found α-globin gene deletions in 3 out of 30 (10 %) patients with MLPA. We propose that MLPA can be used as a second tier test in addition to other techniques such as RDB to identify α-thalassemia carriers in high prevalence regions such as ours, thereby allowing clinicians to provide accurate genetic counselling

Anti-tyrosinase, anti-elastase, and antioxidant activities of some symmetric bisthiocarbohydrazone compounds

Symmetric bisthiocarbohydrazone compounds (1, 2, 3) were obtained by the condensation of thiocarbohydrazide with carbonyl compounds such as isatin (a heterocyclic ketone) and two hydroxyl aldehydes (2-hydroxybenzaldehyde, 2-hydroxy-1-naphthaldehyde) respectively, according to the previously reported methods. These synthesized compounds were evaluated in terms of their anti-tyrosinase, anti-elastase and antioxidant potentials in vitro. All of the tested compounds exhibited anti-tyrosinase and anti-elastase activities. It was observed that the inhibition increased with the increase of bisthiocarbohydrazone concentrations. Compound 1 showed the highest anti-tyrosinase activity. The anti-tyrosinase activity is decreasing in the following order; 2&lt;3&lt;1. Compound 1 showed also the highest anti-elastase activity. The anti-elastase activity is decreasing as 3&lt;2&lt;1. As a result, the most effective compound in terms of anti-tyrosinase and anti-elastase activities is bisthiocarbohydrazone derived from isatin. Compounds 2 and 3 with the hydroxyl substitution showed antioxidant activity close to Trolox. These compounds were found to have significant reducing effects and to be effective scavengers of DPPH