Frequency and severity of myocardial perfusion abnormalities using Tc-99m MIBI SPECT in cardiac syndrome X

BACKGROUND: Cardiac syndrome X is defined by a typical angina pectoris with normal or near normal (stenosis <40%) coronary angiogram with or without electrocardiogram (ECG) change or atypical angina pectoris with normal or near normal coronary angiogram plus a positive none-invasive test (exercise tolerance test or myocardial perfusion scan) with or without ECG change. Studies with myocardial perfusion imaging on this syndrome have indicated some abnormal perfusion scan. We evaluated the role of myocardial perfusion imaging (MPI) and also the severity and extent of perfusion abnormality using Tc-99m MIBI Single Photon Emission Computed Tomography (SPECT) in these patients. METHODS: The study group consisted of 36 patients with cardiac syndrome X. The semiquantitative perfusion analysis was performed using exercise Tc-99m MIBI SPECT. The MPI results were analyzed by the number, location and severity of perfusion defects. RESULTS: Abnormal perfusion defects were detected in 13 (36.10%) cases, while the remaining 23 (63.90%) had normal cardiac imaging. Five of 13 (38.4%) abnormal studies showed multiple perfusion defects. The defects were localized in the apex in 3, apical segments in 4, midventricular segments in 12 and basal segments in 6 cases. Fourteen (56%) of all abnormal segments revealed mild, 7(28%) moderate and 4 (16%) severe reduction of tracer uptake. No fixed defects were identified. The vessel territories were approximately the same in all subjects. The Exercise treadmill test (ETT) was positive in 25(69%) and negative in 11(30%) patients. There was no consistent pattern as related to the extent of MPI defects or exercise test results. CONCLUSION: Our study suggests that multiple perfusion abnormalities with different levels of severity are common in cardiac syndrome X, with more than 30 % of these patients having at least one abnormal perfusion segment. Our findings suggest that in these patients microvascular angina is probably more common than is generally believed

New Techniques for Estimation of Source Parameters : Applications to Airborne Gravity and Pseudo-Gravity Gradient Tensors

Gravity gradient tensor (GGT) data contains the second derivatives of the Earth’s gravitational potential in three orthogonal directions. GGT data can be measured either using land, airborne, marine or space platforms. In the last two decades, the applications of GGT data in hydrocarbon exploration, mineral exploration and structural geology have increased considerably. This work focuses on developing new interpretation techniques for GGT data as well as pseudo-gravity gradient tensor (PGGT) derived from measured magnetic field. The applications of developed methods are demonstrated on a GGT data set from the Vredefort impact structure, South Africa and a magnetic data set from the Särna area, west central Sweden. The eigenvectors of the symmetric GGT can be used to estimate the position of the causative body as well as its strike direction. For a given measurement point, the eigenvector corresponding to the maximum eigenvalue points approximately toward the center of mass of the source body. For quasi 2D structures, the strike direction of the source can be estimated from the direction of the eigenvectors corresponding to the smallest eigenvalues. The same properties of GGT are valid for the pseudo-gravity gradient tensor (PGGT) derived from magnetic field data assuming that the magnetization direction is known. The analytic signal concept is applied to GGT data in three dimensions. Three analytic signal functions are introduced along x-, y- and z-directions which are called directional analytic signals. The directional analytic signals are homogenous and satisfy Euler’s homogeneity equation. Euler deconvolution of directional analytic signals can be used to locate causative bodies. The structural index of the gravity field is automatically identified from solving three Euler equations derived from the GGT for a set of data points located within a square window with adjustable size. For 2D causative bodies with geometry striking in the y-direction, the measured gxz and gzz components of GGT can be jointly inverted for estimating the parameters of infinite dike and geological contact models. Once the strike direction of 2D causative body is estimated, the measured components can be transformed into the strike coordinate system. The GGT data within a set of square windows for both infinite dike and geological contact models are deconvolved and the best model is chosen based on the smallest data fit error.Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 73

Window constrained inversion of gravity gradient tensor data using dike and contact models

We have developed a constrained inversion technique for interpretation of gravity gradient tensor data. For dike and contact models striking in the y-direction, the measured g(xz) and g(zz) components can be jointly inverted for estimating the model parameters horizontal position, depth to the top, thickness, dip angle, and density contrast. For a given measurement point, the strike direction of the gravity gradient tensor caused by a quasi 2D structure can be estimated from the eigenvector corresponding to the smallest eigenvalue. Then, the measured components can be transformed into the strike coordinate system. It is assumed that the maximum of g(zz) is approximately located above the causative body. In the case of gridded data, all measurement points enclosed by a square window centered at the maximum of g(zz) are used to estimate the source parameters. The number of data points used for estimating source parameters is increased by increasing the size of the window. Solutions with the smallest data-fit error were selected as the most reliable solutions from any set of solutions. The gravity gradient tensor data are deconvolved using both dike and contact models within a set of square windows. Then, the model with the smallest data-fit error is chosen as the best model. We studied the effect of random noise and interfering sources using synthetic examples. The method is applied to a gravity gradient tensor data set from the Vredefort impact structure in South Africa. In this particular case, the dike model provides solutions with smaller data-fit errors than the contact model. This supports the idea that in the central dome area there is a predominance of vertical structures related to the formation of the transient crater and subsequent central uplift of the lower and middle crustal material

Copywriting trends in Latvian russian-speaking newspapers in 2000-2007

Šis darbs apraksta mūsdienu tendences divu svarīgu komunikācijas zinātnes jomu– klasiskās krievu – franču virziena avīžu žurnālistikas un mūsdienu sabiedrisko attiecību (Public Relations) mijiedarbībā. Darbā ir aplūkota tēma par sabiedrisko attiecību speciālistu iedarbību uz žurnālistiem, lai samazinātu iespiestās preses komerciālo nozīmīgumu visā plašsaziņas līdzekļu tirgū. Pētījuma pamatā ir pamatotās teorijas (Grounded theory) metodes, kas tiek izmantotas, lai iegūtu objektīvu informāciju par žurnālistu nodomiem un motivāciju no vienas puses, un lielo kompāniju sabiedrisko attiecību dienestiem no otras puses. Kā konkrēts piemērs pētījumiem tika paņemts tāds jēdziens, kā „reklāmas tekstu sastādīšana”, kas nodrošina pētījuma vēsturisko, informatīvo un ekonomisko bāzi.This scientific research is about Public Relations and their interaction with the common journalistic practice in Latvia. It is based on modern qualitative research methods, and it’s goal is to discover, how the modern public relations are influencing the work of press. The emphasis has been put on the conceived attempts to influence the media. Therefore a deep investigationary method – grounded theory-based qualitative research was used to convey a series of special interviews with the journalists. The idea was to uncover the existence of influence by using the keyword denotation method. Other important aspects of interation between media and Public Relations were also uncovered and studied during this research

Construction and validation of the scale of dysfunctional motivational beliefs in high school students

Background: Ineffective motivational beliefs refer to the tendency of people to evaluate performance according to low criteria and lack of effort and perseverance to succeed in homework. Dysfunctional motivational beliefs lead to depression, anxiety, decreased self-esteem, academic self-efficacy, and other psychological problems. Although identifying and measuring dysfunctional motivational beliefs is essential to prevent psychological problems, there is a research gap in the construction and validation of the scale of dysfunctional motivational beliefs in the study population. Aims: This study aimed to construct and validate the scale of dysfunctional motivational beliefs in high school students. Methods: The method of the study was a combination of exploratory type and instrument development model. For this purpose, the foundation was first established through a qualitative study (in the previous study) based on data theorizing, using a semi-structured interview technique that was selected and interviewed with a sample of 15 students. The text of the interviews identified dysfunctional coding and motivational beliefs in behavioral, motivational, emotional, cognitive, personal, school, and family components using 12 methods of exercise, selection, and selectivity (Strauss & Corbin, 2015). In the next stage (the present study), based on the codes obtained from the qualitative part of the research, it became a tool for measuring the dysfunctional motivational beliefs of high school students and validating them. They were studying in 1399. They were selected using Purposive sampling and responded to the dysfunctional motivational beliefs scale. Results: The results of the confirmatory factor analysis showed that the dysfunctional motivational beliefs scale contained 40 questions and consisted of 4 validated factors. Items 1 to 8 related to the factor of academic self-efficacy; Items 9 to 18 related to the testing anxiety factor; Items 19 to 31 related to the factor of academic credentials, and items 32 to 40 were related to the factor of homework value. Indicators of model fit in confirmatory factor analysis confirmed the validity of this scale. Conclusion: In general, the results of the study provided evidence for the validity and reliability of the researcher-made questionnaire of ineffective motivational beliefs as a tool for measuring defective and inhibiting beliefs in the path of academic success of students, and it can be used as a reliable and valid tool for diagnosis used by researchers, therapists, and counselors, teachers should be placed

Successful application of technetium-99m-labeled octreotide acetate scintigraphy in the detection of ectopic adrenocorticotropin-producing bronchial carcinoid lung tumor: a case report

Abstract Introduction The diagnostic efficacy of somatostatin receptor scintigraphy labeling with 111 indium in the localization of tumors has been assessed in a limited number of patients with contradictory outcomes. Here, we describe the case of a patient with an ectopic adrenocorticotropic hormone-producing bronchial carcinoid tumor diagnosed preoperatively using technetium-99m-labeled octreotide acetate scintigraphy. Case presentation A 29-year-old Asian man presented to our hospital with the typical clinical features of Cushing's syndrome, which he had had for a duration of 18 months. The results of a biochemical evaluation revealed he had adrenocorticotropic hormone-dependent Cushing's syndrome. The results of a spiral abdominal computed tomography scan showed he had bilateral adrenal hypertrophy. A magnetic resonance image of the patient's brain showed he had a normal hypophysis. Whole body technetium-99m-labeled octreotide acetate scintigraphy was performed to check for the presence of an ectopic adrenocorticotropic hormone-producing tumor. The scan results showed a small focal increase in uptake in the lower lobe of our patient's right lung, just above his diaphragm. A spiral chest computed tomography scan also revealed a small non-specific lesion in the same region. A transthoracic biopsy was then performed. Pathological evaluation confirmed the diagnosis of a carcinoid tumor, of the adrenocorticotropic hormone-producing type. After surgical removal, the patient's symptoms resolved and significant clinical improvement was achieved. Conclusions This case report shows that technetium-99m-labeled octreotide acetate scintigraphy can effectively detect an ectopic adrenocorticotropic hormone-producing bronchial carcinoid.</p