Practical OCR system based on state of art neural networks

Již dávno bylo jasné že OCR (Optical Character Recognition) je kýženým cí- lem. Na dosažení tohoto cíle bylo vyna- loženo v průběhu desetiletí značné úsilí. V současnosti je tento problém poklá- dán za více méně vyřešený, vzhledem k tomu že na první pohled dnes OCR fun- guje relativně dobře. Bohužel, při bliž- ším pohledu se ukazuje, že momentálně dostupné nástroje spoléhají na kontrole výstupu za pomoci slovníku, případně jazykových modelů. Toto těmto nástro- jům umožňuje porovnávat různé prav- děpodobné interpretace vstupních dat s ohledem na to, jaké výstupy jsou nej- pravděpodobnější na základě toho zda dávají jazykově smysl. Výkonnost těchto nástrojů je ale na nejazyčných datech jako jsou různé alfanumerické kódy pod- statně horší. Tato práce se pokouší o im- plementaci struktury datasetu, syntetic- kého generátoru dat pro výrobu realis- tických trénovacích dat, a konečně o im- plementaci klasifikátoru na bázi strojo- vého učení schopného fungovat na neja- zykových datech lépe než momentálně dostupná řešení.Optical Character Recognition has been recognised as a desirable task since long ago, with much engineering effort put towards its solution over the span of decades with the current general con- sensus considering it to be a more or less "solved" as a problem as by most obvi- ous metrics OCR has been performing well for a long time. At closer inspec- tion of attainable performance with the currently available tools, it turns out that they generally rely on cross referencing results obtained from the visual data with a dictionary or some sophisticated linguistic model. This allows them to probabilistically evalu- ate various interpretations of the visual input and ensure data sanity. Their performance on non-linguistic data like codified alphanumerical strings is sig- nificantly worse. This work attempts to implement a dataset structure, a syn- thetic data generator for the generation of realistic training data and ultimately a deep neural net based classifier capa- ble of outperforming available tools in non-linguistic text recognition

Determination of the spatial and temporal variation of tropospheric water vapour using CGPS networks

Tropospheric water vapour is the main limiting factor in using GPS to determine crustal deformation at highest accuracy. On the other hand, it is an important variable to monitor meteorological and climatic processes. This paper discusses both aspects: the modelling of tropospheric water vapour using meteorological data as well as the determination of the integrated amount of water vapour and its spatiotemporal variation using GPS data. Switzerland has been chosen as experiment area. The Swiss continuous GPS (CGPS) network AGNES is used as a reference network, which represents a realistic scenario for GPS-based water vapour determination. Data of the Swiss numerical weather model aLMo are used for systematic comparison and validation. For the first aspect, integrated tropospheric wet refractivity values are determined from meteorological measurements and compared with GPS path delays. An overall agreement of 1 cm of zenith wet path delay was achieved. For the second aspect a tomographic approach has been developed. A total of 6720 GPS-determined profiles are compared with data of the numerical weather model and radio soundings. The results are statistically evaluated and systematically compared with each other. A correlation between the accuracy and the weather situation was found. Overall, an agreement of 5-7 ppm (refractivity unit) was obtained compared to aLMo. The use of GPS-determined path delays from a permanent GPS network is the recommended method to correct GPS measurements. In all other cases, the two methods presented (COITROPA, COMEDIE) are a feasible alternative to determine path delays accurately. Furthermore, GPS is a convenient application to determine the amount of water vapour in the troposphere. It is demonstrated that the vertical distribution of water vapour can be deduced by applying the tomographic approac

Determination of the spatial and temporal variation of tropospheric water vapour using CGPS networks

Tropospheric water vapour is the main limiting factor in using GPS to determine crustal deformation at highest accuracy. On the other hand, it is an important variable to monitor meteorological and climatic processes. This paper discusses both aspects: the modelling of tropospheric water vapour using meteorological data as well as the determination of the integrated amount of water vapour and its spatiotemporal variation using GPS data. Switzerland has been chosen as experiment area. The Swiss continuous GPS (CGPS) network AGNES is used as a reference network, which represents a realistic scenario for GPS-based water vapour determination. Data of the Swiss numerical weather model aLMo are used for systematic comparison and validation. For the first aspect, integrated tropospheric wet refractivity values are determined from meteorological measurements and compared with GPS path delays. An overall agreement of 1 cm of zenith wet path delay was achieved. For the second aspect a tomographic approach has been developed. A total of 6720 GPS-determined profiles are compared with data of the numerical weather model and radio soundings. The results are statistically evaluated and systematically compared with each other. A correlation between the accuracy and the weather situation was found. Overall, an agreement of 5-7 ppm (refractivity unit) was obtained compared to aLMo. The use of GPS-determined path delays from a permanent GPS network is the recommended method to correct GPS measurements. In all other cases, the two methods presented (COITROPA, COMEDIE) are a feasible alternative to determine path delays accurately. Furthermore, GPS is a convenient application to determine the amount of water vapour in the troposphere. It is demonstrated that the vertical distribution of water vapour can be deduced by applying the tomographic approac

Down-regulation of porin M35 in Moraxella catarrhalis by aminopenicillins and environmental factors and its potential contribution to the mechanism of resistance to aminopenicillins

Objectives The outer membrane protein M35 of Moraxella catarrhalis is an antigenically conserved porin. Knocking out M35 significantly increases the MICs of aminopenicillins. The aim of this study was to determine the biological mechanism of this potentially new antimicrobial resistance mechanism of M. catarrhalis and the behaviour of M35 in general stress situations. Methods PCR using m35-specific primers was used to detect the m35 gene in clinical isolates. The m35 mRNA expression of strains 300, O35E and 415 after exposure to amoxicillin and different stress conditions was measured by real-time PCR and normalized in relation to their 16S rRNA expression. The expression of M35 protein was analysed by SDS-PAGE and western blotting. Results Screening of 52 middle ear isolates resulted in positive PCR products for all tested strains. The analysis of m35 mRNA expression after amoxicillin treatment showed 24%-85% down-regulation compared with the respective amoxicillin-free controls in all three strains tested. Also, analysis of protein concentrations revealed lower M35 expression after growth with amoxicillin. Investigation of M35 during general stress responses showed down-regulation of the porin with growth at 26°C and 42°C, under hyperosmolar stress and under iron restriction. Conclusions The reduced expression of M35 after aminopenicillin exposure indicates a novel resistance mechanism against aminopenicillins in M. catarrhalis, which may be relevant in vivo. The differences in expression after different stress treatments demonstrate that M35 is involved in general stress response

A Reservoir of Moraxella catarrhalis in Human Pharyngeal Lymphoid Tissue

Background. Early exposure of infants and long-term immunity suggest that colonization with Moraxella catarrhalis is more frequent than is determined by routine culture. We characterized a reservoir of M. catarrhalis in pharyngeal lymphoid tissue. Methods. Tissue from 40 patients (median age, 7.1 years) undergoing elective tonsillectomy and/or adenoidectomy was analyzed for the presence of M. catarrhalis by culture, real-time DNA and RNA polymerase chain reaction (PCR), immunohistochemical analysis (IHC), and fluorescent in situ hybridization (FISH). Histologic sections were double stained for M. catarrhalis and immune cell markers, to characterize the tissue distribution of the organism. Intracellular bacteria were identified using confocal laser scanning microscopy (CLSM). Results. Twenty-nine (91%) of 32 adenoids and 17 (85%) of 20 tonsils were colonized with M. catarrhalis. Detection rates for culture, DNA PCR, RNA PCR, IHC, and FISH were 7 (13%) of 52, 10 (19%) of 52, 21 (41%) of 51, 30 (61%) of 49, and 42 (88%) of 48, respectively (P < .001). Histologic analysis identified M. catarrhalis in crypts, intraepithelially, subepithelially, and (using CLSM) intracellularly. M. catarrhalis colocalized with macrophages and B cells in lymphoid follicles. Conclusions. Colonization by M. catarrhalis is more frequent than is determined by surface culture, because the organism resides both within and beneath the epithelium and invades host cell

Physiologic Cold Shock Increases Adherence of Moraxella catarrhalis to and Secretion of Interleukin 8 in Human Upper Respiratory Tract Epithelial Cells

Moraxella catarrhalis, a major nasopharyngeal pathogen of the human respiratory tract, is exposed to rapid and prolonged downshifts of environmental temperature when humans breathe cold air. In the present study, we show that a 26°C cold shock up-regulates the expression of UspA1, a major adhesin and putative virulence factor of M. catarrhalis, by prolonging messenger RNA half-life. Cold shock promotes M. catarrhalis adherence to upper respiratory tract cells via enhanced binding to fibronectin, an extracellular matrix component that mediates bacterial attachment. Exposure of M. catarrhalis to 26°C increases the outer membrane protein-mediated release of the proinflammatory cytokine interleukin 8 in pharyngeal epithelial cells. Furthermore, cold shock at 26°C enhances the binding of salivary immunoglobulin A on the surface of M. catarrhalis. These data indicate that cold shock at a physiologically relevant temperature of 26°C affects the nasopharyngeal host-pathogen interaction and may contribute to M. catarrhalis virulenc

Topical curcumin can inhibit deleterious effects of upper respiratory tract bacteria on human oropharyngeal cells in vitro: potential role for patients with cancer therapy induced mucositis?

Purpose: Curcumin exerts its anti-inflammatory activity via inhibition of nuclear factor κB. Oropharyngeal epithelia and residing bacteria closely interact in inflammation and infection. This in vitro model investigated the effects of curcumin on bacterial survival, adherence to, and invasion of upper respiratory tract epithelia, and studied its anti-inflammatory effect. We aimed to establish a model, which could offer insights into the host-pathogen interaction in cancer therapy induced mucositis. Methods: Moraxella catarrhalis (Mcat) and the oropharyngeal epithelial cell line Detroit 562 were used. Time-kill curves assessed the inhibition of bacterial growth and adherence assays and gentamicin protection assays determined the effect of curcumin-preincubated cells on bacterial adherence and invasion. Curcumin-mediated inhibition of pro-inflammatory activation by Mcat was determined via interleukin-8 concentrations in the supernatants. The synergistic role of secretory IgA (sIgA) on adherence was investigated. Results: Curcumin was bactericidal at concentrations >50µM. Preincubation of Detroit cells for 60min demonstrated that concentrations >100µM inhibited bacterial adherence. Together with sIgA, curcumin inhibited adherence at concentrations ≥50µM. Both 100 and 200µM curcumin significantly inhibited Mcat cell invasion. Finally, curcumin inhibited Mcat-induced pro-inflammatory activation by strongly suppressing IL-8 release. At a concentration of 200µM, 10min of curcumin exposure inhibited IL-8 release significantly, and complete suppression required a pre-exposure time of ≥45min. Conclusion: Curcumin, in clinically relevant concentrations for topical use, displayed strong antibacterial effect against a facultative upper respiratory tract pathogen by inhibiting bacterial growth, adherence, invasion, and pro-inflammatory activation of upper respiratory tract epithelial cells in vitr

Unveiling electrotransformation of Moraxella catarrhalis as a process of natural transformation

The human respiratory tract pathogen Moraxella catarrhalis is a naturally competent microorganism. However, electrotransformation has long been used to introduce foreign DNA into this organism. This study demonstrated that electrotransformants obtained with linear or circular nonreplicating plasmid DNA originated exclusively from natural transformation processes taking place during the recovery phase after the application of current. Only replicating plasmid DNA could be introduced into M. catarrhalis by electrotransformation, in a type IV pilus-independent manner. Electrotransformation with homologous genomic DNA indicated that restriction of double-stranded DNA was independent of type III restriction-methylation systems. Nontransformability of M. catarrhalis by electrotransformation was observed using double- as well as single-stranded DNA. In addition, the study showed that natural competence is a very constant feature of M. catarrhali

Psychosocial Deprivation, Executive Functions, and the Emergence of Socio-Emotional Behavior Problems

Early psychosocial deprivation can negatively impact the development of executive functions (EFs). Here we explore the impact of early psychosocial deprivation on behavioral and physiological measures (i.e., event-related potentials; ERPs) of two facets of EF, inhibitory control and response monitoring, and their associations with internalizing and externalizing outcomes in the Bucharest Early Intervention Project (BEIP; Zeanah et al., 2003). This project focuses on two groups of children placed in institutions shortly after birth and then randomly assigned in infancy to either a foster care intervention or to remain in their current institutional setting. A group of community controls was recruited for comparison. The current study assesses these children at 8-years of age examining the effects of early adversity, the potential effects of the intervention on EF and the role of EF skills in socio-emotional outcomes. Results reveal exposure to early psychosocial deprivation was associated with impaired inhibitory control on a flanker task. Children in the foster care intervention exhibited better response monitoring compared to children who remained in the institution on the error-related positivity (Pe). Moreover, among children in the foster care intervention those who exhibited larger error-related negativity (ERN) responses had lower levels of socio-emotional behavior problems. Overall, these data identify specific aspects of EF that contribute to adaptive and maladaptive socio-emotional outcomes among children experiencing early psychosocial deprivation

Immunosympathectomy and avoidance behaviour in mice

W. B. Cannon and his co-workers during the 1930's had purported to have demonstrated the non-essential character of the sympathetic nervous system's role in mediating emotion, but later workers using behavioural studies have tended to implicate the system in emotional behaviour. In this thesis an immunological technique was used to induce hypotrophic growth in the sympathetic nervous system of neonatal rodents. The injection technique used a split- litter design with the control neonates being injected with normal horse serum (NHS) .Following failure to obtain behavioural separation between the immunosympathectomized (IS) and the control (NHS) litter- mates using standard active and passive avoidance tasks it was argued that the time course of these procedures allowed ample opportunity for internal compensatory mechanisms to mask any essential differences. Accordingly an avoidance task (startle response) with a very short time course was used to test the animals. This task also failed to show unequivocal behavioural separation. Measuring the catecholamine metabolism of the adrenals some evidence was obtained which showed that IS mice metabolized larger amounts of the sympathetic nervous system's transmitter substance, noradrenaline, when subjected to a novel or an avoidance task. Evidence was examined on the essential interaction between the sympatho-adrenal medulla and the pituitary-adrenal cortex axis. It was concluded that certain controls are essential if an unambiguous demonstration is to be made of these two important central nervous system's efferent outflows in emotional states. IS mice were placed on free operant avoidance schedules in specially constructed apparatus. The final experiment reported concerns an attempt to further reduce the range of IS mice adaptive responses by the use of an inclined alleyway avoidance task interpolated between two equal periods of free operant avoidance responding. It was finally concluded that unequivocal behavioural separation, using avoidance tasks, has not been shown between IS and control litterraate mice either in this thesis or other published work. Hypotheses are discussed as to why this should be so