944 resultados para False spider mites
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We propose a robust method for mosaicing of document images using features derived from connected components. Each connected component is described using the Angular Radial Tran. form (ART). To ensure geometric consistency during feature matching, the ART coefficients of a connected component are augmented with those of its two nearest neighbors. The proposed method addresses two critical issues often encountered in correspondence matching: (i) The stability of features and (ii) Robustness against false matches due to the multiple instances of characters in a document image. The use of connected components guarantees a stable localization across images. The augmented features ensure a successful correspondence matching even in the presence of multiple similar regions within the page. We illustrate the effectiveness of the proposed method on camera captured document images exhibiting large variations in viewpoint, illumination and scale.
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The present challenge in drug discovery is to synthesize new compounds efficiently in minimal time. The trend is towards carefully designed and well-characterized compound libraries because fast and effective synthesis methods easily produce thousands of new compounds. The need for rapid and reliable analysis methods is increased at the same time. Quality assessment, including the identification and purity tests, is highly important since false (negative or positive) results, for instance in tests of biological activity or determination of early-ADME parameters in vitro (the pharmacokinetic study of drug absorption, distribution, metabolism, and excretion), must be avoided. This thesis summarizes the principles of classical planar chromatographic separation combined with ultraviolet (UV) and mass spectrometric (MS) detection, and introduces powerful, rapid, easy, low-cost, and alternative tools and techniques for qualitative and quantitative analysis of small drug or drug-like molecules. High performance thin-layer chromatography (HPTLC) was introduced and evaluated for fast semi-quantitative assessment of the purity of synthesis target compounds. HPTLC methods were compared with the liquid chromatography (LC) methods. Electrospray ionization mass spectrometry (ESI MS) and atmospheric pressure matrix-assisted laser desorption/ionization MS (AP MALDI MS) were used to identify and confirm the product zones on the plate. AP MALDI MS was rapid, and easy to carry out directly on the plate without scraping. The PLC method was used to isolate target compounds from crude synthesized products and purify them for bioactivity and preliminary ADME tests. Ultra-thin-layer chromatography (UTLC) with AP MALDI MS and desorption electrospray ionization mass spectrometry (DESI MS) was introduced and studied for the first time. Because of the thinner adsorbent layer, the monolithic UTLC plate provided 10 100 times better sensitivity in MALDI analysis than did HPTLC plates. The limits of detection (LODs) down to low picomole range were demonstrated for UTLC AP MALDI and UTLC DESI MS. In a comparison of AP and vacuum MALDI MS detection for UTLC plates, desorption from the irregular surface of the plates with the combination of an external AP MALDI ion source and an ion trap instrument provided clearly less variation in mass accuracy than the vacuum MALDI time-of-flight (TOF) instrument. The performance of the two-dimensional (2D) UTLC separation with AP MALDI MS method was studied for the first time. The influence of the urine matrix on the separation and the repeatability was evaluated with benzodiazepines as model substances in human urine. The applicability of 2D UTLC AP MALDI MS was demonstrated in the detection of metabolites in an authentic urine sample.
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A critical assessment of a published paper (by Agrawal) is presented. The procedure proposed and used by Agrawal to distinguish a false compensation effect from a true one is shown not to be correct.
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The main question of my doctoral thesis is whether ufology and UFO experiences are or can be explained as religious phenomena. My research is theoretical in the sense that I combine and systematise cultural scientific knowledge concerning the religiosity of ufology and UFO experiences and complete this theoretical effort with empirical subject matter. The research material for my study consists of theoretical literature and empirical texts written by ufologists and those who have had UFO experiences. I defined the material in a way that it became full and extensive with regard to ufology, stories about UFO experiences and the cultural scientific literature concerning them. In addition, I present a source criticism for the literature because it is in part informal. The method is analysing and synthesising the material in the context of spiral of hermeneutic inferential process. Definitions of religion, ufology and UFO experience, developed by myself, serve as guide lines for the process. The conclusions of my research are as follows. For the most part, ufology and UFO experiences belong to the category of religion and only a fraction of these instances can be explained as something else, for example psychiatric phenomena. From the religious viewpoint I explain ufology and UFO experiences on four different but interlinked levels: historical, comparative, sociological and psychological. Historically ufology and UFO experiences include esoteristic, Christian and folk religious elements. In addition UFO experiences have significant similarities with folk religious stories and shamanistic experiences. From the perspective of the sociology, of religion ufology and UFO experiences can be analysed as products of our scientific and technological Western culture. Social crisis and social psychological group mechanisms affect the appearance of ufological ideas and UFO experiences. Psychologically, in the background of religious UFO experiences there can be found several factors, such as wishful thinking. Concerning UFO sightings these are misinterpretations of certain ordinary and some rare or exotic natural and technical phenomena. Intense UFO experiences, such as UFO abductions, are stimulated for the most part by hallucinations, sleep paralysis disorders, lively fantasies (in case of fantasy prone personalities) and false memories. In group cases social pressure, small group delusion and the guilt of exposing the true nature of a story come into play. A UFO experience can be traumatising because of certain inferential mechanisms and cognitive dissonance involved in the process of conversion as a UFO experiencer. UFO religiosity is a cross cultural, widespread and a significant field of phenomena, which can offer insight about religious developments in the future. However, UFO religiosity has not been studied extensively. This research is one effort to address this lack of documentation. The motivation behind my thesis was to make ufology and UFO experiences more understandable.
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Yao, Begg, and Livingston (1996, Biometrics 52, 992-1001) considered the optimal group size for testing a series of potentially therapeutic agents to identify a promising one as soon as possible for given error rates. The number of patients to be tested with each agent was fixed as the group size. We consider a sequential design that allows early acceptance and rejection, and we provide an optimal strategy to minimize the sample sizes (patients) required using Markov decision processes. The minimization is under the constraints of the two types (false positive and false negative) of error probabilities, with the Lagrangian multipliers corresponding to the cost parameters for the two types of errors. Numerical studies indicate that there can be a substantial reduction in the number of patients required.
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Background Epidemiological and clinical studies suggest comorbidity between prostate cancer (PCA) and cardiovascular disease (CVD) risk factors. However, the relationship between these two phenotypes is still not well understood. Here we sought to identify shared genetic loci between PCA and CVD risk factors. Methods We applied a genetic epidemiology method based on conjunction false discovery rate (FDR) that combines summary statistics from different genome-wide association studies (GWAS), and allows identification of genetic overlap between two phenotypes. We evaluated summary statistics from large, multi-centre GWA studies of PCA (n = 50 000) and CVD risk factors (n = 200 000) [triglycerides (TG), low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol, systolic blood pressure, body mass index, waist-hip ratio and type 2 diabetes (T2D)]. Enrichment of single nucleotide polymorphisms (SNPs) associated with PCA and CVD risk factors was assessed with conditional quantile-quantile plots and the Anderson-Darling test. Moreover, we pinpointed shared loci using conjunction FDR. Results We found the strongest enrichment of P-values in PCA was conditional on LDL and conditional on TG. In contrast, we found only weak enrichment conditional on HDL or conditional on the other traits investigated. Conjunction FDR identified altogether 17 loci; 10 loci were associated with PCA and LDL, 3 loci were associated with PCA and TG and additionally 4 loci were associated with PCA, LDL and TG jointly (conjunction FDR < 0.01). For T2D, we detected one locus adjacent to HNF1B. Conclusions We found polygenic overlap between PCA predisposition and blood lipids, in particular LDL and TG, and identified 17 pleiotropic gene loci between PCA and LDL, and PCA and TG, respectively. These findings provide novel pathobiological insights and may have implications for trials using targeting lipid-lowering agents in a prevention or cancer setting.
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We consider the problem of tracking a maneuvering target in clutter. In such an environment, missed detections and false alarms make it impossible to decide, with certainty, the origin of received echoes. Processing radar returns in cluttered environments consists of three functions: 1) target detection and plot formation, 2) plot-to-track association, and 3) track updating. Two inadequacies of the present approaches are 1) Optimization of detection characteristics have not been considered and 2) features that can be used in the plot-to-track correlation process are restricted to a specific class. This paper presents a new approach to overcome these limitations. This approach facilitates tracking of a maneuvering target in clutter and improves tracking performance for weak targets.
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Stallard (1998, Biometrics 54, 279-294) recently used Bayesian decision theory for sample-size determination in phase II trials. His design maximizes the expected financial gains in the development of a new treatment. However, it results in a very high probability (0.65) of recommending an ineffective treatment for phase III testing. On the other hand, the expected gain using his design is more than 10 times that of a design that tightly controls the false positive error (Thall and Simon, 1994, Biometrics 50, 337-349). Stallard's design maximizes the expected gain per phase II trial, but it does not maximize the rate of gain or total gain for a fixed length of time because the rate of gain depends on the proportion: of treatments forwarding to the phase III study. We suggest maximizing the rate of gain, and the resulting optimal one-stage design becomes twice as efficient as Stallard's one-stage design. Furthermore, the new design has a probability of only 0.12 of passing an ineffective treatment to phase III study.
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The aim of this dissertation is to provide conceptual tools for the social scientist for clarifying, evaluating and comparing explanations of social phenomena based on formal mathematical models. The focus is on relatively simple theoretical models and simulations, not statistical models. These studies apply a theory of explanation according to which explanation is about tracing objective relations of dependence, knowledge of which enables answers to contrastive why and how-questions. This theory is developed further by delineating criteria for evaluating competing explanations and by applying the theory to social scientific modelling practices and to the key concepts of equilibrium and mechanism. The dissertation is comprised of an introductory essay and six published original research articles. The main theses about model-based explanations in the social sciences argued for in the articles are the following. 1) The concept of explanatory power, often used to argue for the superiority of one explanation over another, compasses five dimensions which are partially independent and involve some systematic trade-offs. 2) All equilibrium explanations do not causally explain the obtaining of the end equilibrium state with the multiple possible initial states. Instead, they often constitutively explain the macro property of the system with the micro properties of the parts (together with their organization). 3) There is an important ambivalence in the concept mechanism used in many model-based explanations and this difference corresponds to a difference between two alternative research heuristics. 4) Whether unrealistic assumptions in a model (such as a rational choice model) are detrimental to an explanation provided by the model depends on whether the representation of the explanatory dependency in the model is itself dependent on the particular unrealistic assumptions. Thus evaluating whether a literally false assumption in a model is problematic requires specifying exactly what is supposed to be explained and by what. 5) The question of whether an explanatory relationship depends on particular false assumptions can be explored with the process of derivational robustness analysis and the importance of robustness analysis accounts for some of the puzzling features of the tradition of model-building in economics. 6) The fact that economists have been relatively reluctant to use true agent-based simulations to formulate explanations can partially be explained by the specific ideal of scientific understanding implicit in the practise of orthodox economics.
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Degradation of RNA in diagnostic specimens can cause false-negative test results and potential misdiagnosis when tests rely on the detection of specific RNA sequence. Current molecular methods of checking RNA integrity tend to be host species or group specific, necessitating libraries of primers and reaction conditions. The objective here was to develop a universal (multi-species) quality assurance tool for determining the integrity of RNA in animal tissues submitted to a laboratory for analyses. Ribosomal RNA (16S rRNA) transcribed from the mitochondrial 16S rDNA was used as template material for reverse transcription to cDNA and was amplified using polymerase chain reaction (PCR). As mitochondrial DNA has a high level of conservation, the primers used were shown to reverse transcribe and amplify RNA from every animal species tested. Deliberate degradation of rRNA template through temperature abuse of samples resulted in no reverse transcription and amplification. Samples spiked with viruses showed that single-stranded viral RNA and rRNA in the same sample degraded at similar rates, hence reverse transcription and PCR amplification of 16S rRNA could be used as a test of sample integrity and suitability for analysis that required the sample's RNA, including viral RNA. This test will be an invaluable quality assurance tool for determination of RNA integrity from tissue samples, thus avoiding erroneous test results that might occur if degraded target RNA is used unknowingly as template material for reverse transcription and subsequent PCR amplification.
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This study evaluates the effectiveness and social implications of home monitoring of 31 infants at risk of sudden infant death syndrome (SIDS). Thirteen siblings of children dying of SIDS, nine near miss SIDS infants and nine preterm infants with apnoea persisting beyond 40 weeks post conceptual age were monitored from a mean age of 15 days to a mean of 10 months. Chest movement detection monitors were used in 27 and thoracic impedance monitors in four. Genuine apnoeic episodes were reported by 21 families, and 13 infants required resuscitation. Apnoeic episodes occurred in all nine preterm infants but in only five (38%) of the siblings of SIDS (P<0.05). Troublesome false alarms were a major problem occurring with 61% of the infants and were more common with the preterm infants than the siblings of SIDS. All but two couples stated that the monitor decreased anxiety and improved their quality of life. Most parents accepted that the social restrictions imposed by the monitor were part of the caring process but four couples were highly resentful of the changes imposed on their lifestyle. The monitors used were far from ideal with malfunction occurring in 17, necessitating replacement in six, repair in six and cessation of monitoring in three. The parents became ingenious in modifying the monitors to their own individual requirements Although none of these 31 ‘at risk’ infants died the study sample was far too small to conclude whether home monitoring prevented any cases of SIDS.
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Talking about symptoms during medical consultation. A conversation analytical study of doctors questions This linguistically oriented conversation analytic study investigates doctors questions and patients answers during medical consultation. The focus is on 1) the syntactic constructions of the doctors questions concerning the patients symptoms, 2) the function of different types of syntactic constructions, and 3) the sequential placement of the questions. The data used in the study consist of 57 videotaped doctor patient encounters in Finnish primary health care. The study shows that the traditional division between open and closed questions is vague and needs to be examined further. Open wh-questions and closed yes/no questions form heterogeneous classes: some of the closed questions can be treated as open and vice versa. Wh-questions which occur during the physical examination are often constructed to elicit short answers. These questions can consist of one word (e.g. milloin when ) which does not move to a new topic but supports the unfinished activity of palpation. During the verbal examination, wh-questions are formulated to elicit long descriptions as answers. For example, by asking mites + X ( what about + X), the doctor can open up a new topic and simultaneously give the patient the opportunity to discuss the topic from his/her perspective. Almost half of the yes/no questions project longer than just a minimal answer (e.g. a short confirmation or rejection). In these questions, the doctors use verbal elements which show that more than just a minimal answer is required. They can, for example, add an indefinite element (joku some or mitään any ) to a yes/no question, add a conjunctive vai ( or ) to the end of the question and thus open a space for various types of answers, or add a suggested answer to the question. In addition, the results show that declarative questions not only check understanding, but display the doctor s diagnosing process, check whether the doctor can move on to the next topic or action, and display implicitly the doctor s idea of what is connected and what is relevant. One aim of the study is to describe how different syntactic structures work together. A typical question chain consists of two or three questions. The first question is an open wh-question that elicits a new topic and creates different types of presuppositions. Contingent questions are constructed as yes/no questions that seek an affirmative answer or as declarative sentences that seek confirmation. Contingent questions can function as repair initiators and thus support achieving mutual understanding. Therefore, they are tools for the doctor to construct a description of the medical problem collaboratively with the patient. The results add to the results of previous studies on questions in medical consultation, but also suggest some corrections. They provide additional evidence for the idea that different types of syntactic constructions are useful in different types of settings. However, they also show that the variety of questions that doctors use is more manifold and diverse than the variety introduced in earlier studies and textbooks.
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Vilho Helanen (1899 1952) was a right-wing opinion leader in interwar Finland. But following the Second World War, the political situation in the country changed dramatically, and Helanen lost his job as well as his influential social station. He began to write detective fiction, and between 1946 and 1952 published seven novels (one had already been published in 1941). The novels protagonist is Kaarlo Rauta, a lawyer who acts as a private investigator. This doctoral dissertation analyzes the Rauta series from three different points of view. It investigates the extent to which the author s life and his strong political background appears in the series. The study also situates the series within Finnish society during and after the war. Finally, the study examines the Rauta series in terms of the genre conventions of detective fiction, that is, the study compares the Rauta series with other Finnish crime fiction and international crime fiction written during the 1940s. The Iron and The Cross Spider uses the term citizenship education when analyzing how Helanen implicitly continued his political teaching when writing crime fiction. The series includes a didactic register, which instructs the middle class in appropriate behaviour and manners, and the social roles entailed by gender. A special area of focus in this didacticism are norms of correct masculinity and femininity. The study devotes specific attention to the status of character in the series. The masculine detective and his beautiful wife are prominent, as is the fictive community and the tensions that criss-cross it. After the war, the Rauta series takes on a positive tone. Men can earn their place in society by fighting at the front, and after the war a homosocial bond exists between all the former soldiers. Women are shut out of the war experience. The detective hero has served in the war, but he is physically and psychologically untouched by it. The community is threatened by artists and immoral bohemians, but not the working class. Artists have affairs outside of marriage and abnormal sexual habits. The members of the upper class are also described as immoral in the series. Sadistic sexuality is often characteristic of the criminals, who are mostly femme fatales in the fashion of hard-boiled detective stories and film noir. Also, strong feelings have a negative connotation in the series, and showing them is forbidden behaviour. Men become criminals when they are insufficiently masculine or when they have not carried out their duty by fighting in the war. Helanen portrayed the communists, his political opponents from the 1930s, as criminals in his post-war series, but they were not openly represented as Russians or communists. Instead, Helanen used the cross spider as their symbol, a symbol which the readers of the time would recognize.
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Forest health surveillance (FHS) of hardwood plantations commenced in Queensland in 1997 as plantations expanded following a state government planting initiative arising from the national 2020 forest policy vision. The estate was initially characterised by a large number of small plantations (10-50 ha), although this has changed more recently with the concentration of larger plantations in the central coast and South Burnett regions. Due to the disparate nature of the resource, drive- and walkthrough surveys of subsets of plantations have been undertaken in preference to aerial surveys. FHS has been effective in detecting a number of new hardwood pests in Queensland including erinose mites (Rhombacus and Acalox spp.), western white gum plate galler (Ophelimus sp.), Creiis psyllid and bronzing bug (Thaumastocoris sp.), in evaluating their potential impact and assisting in focussing future research efforts. Since 2003 there has been an increased emphasis on training operational staff to take a greater role in identifying and reporting on forest health issues. This has increased their awareness of forest health issues, but their limited time to specifically survey and report on pests and diseases, and high rates of staff turnover, necessitate frequent ongoing training. Consequently, common and widespread problems such as quambalaria shoot blight (Quambalaria pitereka), chrysomelid leaf beetles (mainly Paropsis atomaria) and erinose mites may be under-reported or not reported, and absence data may often not be recorded at all. Comment is made on the future directions that FHS may take in hardwood plantations in Queensland.
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This paper presents a Multi-Hypotheses Tracking (MHT) approach that allows solving ambiguities that arise with previous methods of associating targets and tracks within a highly volatile vehicular environment. The previous approach based on the Dempster–Shafer Theory assumes that associations between tracks and targets are unique; this was shown to allow the formation of ghost tracks when there was too much ambiguity or conflict for the system to take a meaningful decision. The MHT algorithm described in this paper removes this uniqueness condition, allowing the system to include ambiguity and even to prevent making any decision if available data are poor. We provide a general introduction to the Dempster–Shafer Theory and present the previously used approach. Then, we explain our MHT mechanism and provide evidence of its increased performance in reducing the amount of ghost tracks and false positive processed by the tracking system.