The prediction of porosity in the Permian (Zechstein 2) carbonate of eastern Netherlands using seismic data

Geophysics ◽  
1979 ◽  
Vol 44 (9) ◽  
pp. 1502-1517 ◽  
Author(s):  
G. T. F. R. Maureau ◽  
D. H. van Wijhe
Keyword(s):  
Seismic Data ◽  
Acoustic Impedance ◽  
Phase 1 ◽  
Depositional Environments ◽  
Complex Nature ◽  
High Porosity ◽  
Two Phase ◽  
Seismic Section ◽  
Model Study ◽  
Phase Study

The depositional model of the Zechstein 2 carbonate section is of such a complex nature that it is not possible to predict high‐porosity zones solely from geologic data. We describe a two‐phase study into determination and prediction of porosities in the Zechstein 2 carbonate in the eastern Netherlands. Phase 1 was the basic feasibility study and consisted of two parts, namely, a model study followed by a well‐log study. In both parts, acoustic impedance logs were filtered to test the feasibility of resolving porosity changes within the frequency range of seismic data. Based on our comprehensive model of the environment of deposition of the Zechstein evaporites, a number of acoustic impedance logs were constructed, each log representing a particular environment. These logs then were filtered with a suite of band‐pass filters. It was our observation that the gross changes in porosity were easily recognized. The model study was followed by a study of acoustic impedance logs from actual downhole measurements taken over intervals with depositional environments similar to those represented in the model study. In spite of geologic variations, the changes in porosity were easily observable. Phase 2 involved the prediction and verification of porosity. An exploration well, planned to penetrate the Zechstein 2 carbonate, was connected to a previously drilled carbonate test by a good quality seismic section. In the previous well, porous limestone approximately 60 m in thickness was penetrated. From the combined well and seismic data, we predicted that a similar development of porosity could be expected in the new location. Subsequent drilling proved the presence of porous carbonate approximately 50 m in thickness developed in an environment of deposition similar to that encountered in the other well. This technique has allowed us to predict reservoir porosity and will be used to develop new structural/stratigraphic prospects.

Endometrial Adenocarcinoma in SurePath™ Cervical Samples: Cytological Features Revisited

2016 ◽  
Vol 60 (1) ◽  
pp. 46-52 ◽  
Author(s):  
Nalini Gupta ◽  
John Crossley ◽  
Nick Dudding ◽  
John H.F. Smith
Keyword(s):  
Phase 1 ◽  
Endometrial Adenocarcinoma ◽  
Nuclear Chromatin ◽  
Phase 2 ◽  
Cervical Lesions ◽  
Two Phase ◽  
Endometrial Cells ◽  
Phase Study ◽  
Cytological Features ◽  
Liquid Based Cytology

Objective: The cytomorphological criteria of malignant endometrial lesions in cervical samples are less well described than those of cervical lesions. We wished to investigate if there were features in SurePath™ liquid-based cytology samples that would facilitate more accurate differentiation between benign and malignant endometrial cells. Study Design: This was a two-phase study, with a review of all SurePath™ samples reported as endometrial adenocarcinoma (n = 42) evaluating 12 cytological features in the first phase. In phase 2 (test set), all initial cases plus an additional 83 cases were reviewed using these 12 cytological features to predict the outcome. Results: Out of 12 cytological features evaluated in phase 1 (training set), nuclear chromatin pattern, apoptotic bodies and tingible body macrophages were found to be the most significant features determining malignant histological outcome. These 12 cytological features were re-evaluated in phase 2 (n = 125). Of 125 cases, 54 had a benign and 71 had a malignant or premalignant histological outcome, with a positive predictive value of 56.8%. Conclusion: Granular nuclear chromatin, tingible body macrophages and apoptosis in the background are the most significant factors in determining whether endometrial cells present in cervical samples represent malignancy or are benign. Using these features, relatively accurate predictions of endometrial pathology can be made.

scholarly journals Evaluation of the clinical practice of aminoglycoside use in paediatric patients in Kenya: findings and implications for lower-middle income countries

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Elias Joseph Onyango ◽  
Faith Okalebo ◽  
Margaret Oluka ◽  
Rosaline Kinuthia ◽  
Loice Achieng ◽  
...  
Keyword(s):  
Phase 1 ◽  
Therapeutic Index ◽  
Therapeutic Drug ◽  
National Guidelines ◽  
Two Phase ◽  
Middle Income ◽  
Face To Face ◽  
Skill Gaps ◽  
Aminoglycoside Therapy ◽  
Phase Study

Abstract Objectives To evaluate the practice of aminoglycoside use/monitoring in Kenya and explore healthcare worker (HCW) perceptions of aminoglycoside monitoring to identify gaps and opportunities for future improvements, given the low therapeutic index of aminoglycosides. Methods This was a two-phase study whereby we reviewed patients’ medical records at Kenyatta National Hospital (October–December 2016) in Phase 1 and interviewed HCWs face to face in Phase 2. Outcome measures included describing and evaluating the practice of aminoglycoside use and monitoring and compliance to guidelines. Data were analysed using descriptive and inferential analysis. Results Overall, out of the 2318 patients admitted, 192 patients (8.3%) were prescribed an aminoglycoside, of which 102 (53.1%) had aminoglycoside doses that did not conform to national guidelines. Aminoglycoside-related adverse effects were suspected in 65 (33.9%) patients. Monitoring of aminoglycoside therapy was performed in only 17 (8.9%) patients, with no therapeutic drug monitoring (TDM), attributed mainly to knowledge and skill gaps and lack of resources. Out of the 28 recruited HCWs, 18 (64.3%) needed training in how to perform and interpret TDM results. Conclusions The practice of using and monitoring aminoglycosides was suboptimal, raising concerns around potential avoidable harm to patients. The identified gaps could form the basis for developing strategies to improve the future use of aminoglycosides, not only in Kenya but also in other countries with similar settings and resources.

Epidemiological aspects of psychiatric disorder in a Dutch health area

1987 ◽  
Vol 17 (2) ◽  
pp. 495-505 ◽  
Author(s):  
Paul Hodiamont ◽  
Nelly Peer ◽  
No Syben
Keyword(s):  
Psychiatric Disorder ◽  
Phase 1 ◽  
Epidemiological Data ◽  
Chronically Ill ◽  
Industrialized Countries ◽  
Two Phase ◽  
Health Area ◽  
Phase Study ◽  
Dutch Health ◽  
The Unemployed

SynopsisA two-phase study of psychiatric prevalence has been carried out among the inhabitants (aged 18–64) of a Dutch health area (Nijmegen). In phase 1, a random sample of 3232 persons answered the GHQ–30 (response rate:75%). In phase 2,486 of the respondents were interviewed withthe full PSE within two weeks. The relationship of PSE-‘caseness’ (ID ≥ 5) and GHQ score was expressed in a logistic regression model, the parameters of which showed strong agreement with the Canberra results, for all socio-demographic variables examined, except for urbanization. means of the logistic model the point-prevalence of PSE cases was calculated at 7·3% (range5·5%-9·2%).Prevalence did not differ significantly in men and women. Higher case rates were found in age category of 55–59 years, among divorced and widowed persons, the lower educational and occupational levels, the unemployed, chronically ill and unable to work, and with city people. This study adds further evidence to a growing body of epidemiological data suggesting similar rates and patterns of psychiatric disorder in populations in industrialized countries.

High-resolution acoustic impedance inversion to characterize turbidites at Marlim Field, Campos Basin, Brazil

2014 ◽  
Vol 2 (3) ◽  
pp. T143-T153 ◽  
Author(s):  
Tatiane M. Nascimento ◽  
Paulo T. L. Menezes ◽  
Igor L. Braga
Keyword(s):  
High Resolution ◽  
Seismic Data ◽  
Acoustic Impedance ◽  
Structural Information ◽  
Low Frequency ◽  
Seismic Inversion ◽  
Background Model ◽  
Rock Properties ◽  
High Porosity ◽  
Campos Basin

Seismic inversion is routinely used to determine rock properties, such as acoustic impedance and porosity, from seismic data. Nonuniqueness of the solutions is a major issue. A good strategy to reduce this inherent ambiguity of the inversion procedure is to introduce stratigraphic and structural information a priori to better construct the low-frequency background model. This is particularly relevant when studying heterogeneous deepwater turbidite reservoirs that form prolific, but complex, hydrocarbon plays in the Brazilian offshore basins. We evaluated a high-resolution inversion workflow applied to 3D seismic data at Marlim Field, Campos Basin, to recover acoustic impedance and porosity of the turbidites reservoirs. The Marlim sandstones consist of an Oligocene/Miocene deepwater turbidite system forming a series of amalgamated bodies. The main advantage of our workflow is to incorporate the interpreter’s knowledge about the local stratigraphy to construct an enhanced background model, and then extract a higher resolution image from the seismic data. High-porosity zones were associated to the reservoirs facies; meanwhile, the nonreservoir facies were identified as low-porosity zones.

scholarly journals Use of Attributes on 3D Seismic Data for Studying Mishrif Formation in East Abu-Amoud Field, South-Eastern Iraq

2021 ◽  
pp. 4802-4809
Author(s):  
Mohammed H. Al-Aaraji ◽  
Hussein H. Karim
Keyword(s):  
Seismic Data ◽  
Acoustic Impedance ◽  
Seismic Attributes ◽  
3D Seismic ◽  
Seismic Section ◽  
Reflected Waves ◽  
South Eastern ◽  
Seismic Sections ◽  
Sonic Logs ◽  
3D Seismic Data

      The seismic method depends on the nature of the reflected waves from the interfaces between layers, which in turn depends on the density and velocity of the layer, and this is called acoustic impedance. The seismic sections of the East Abu-Amoud field that is located in Missan Province, south-eastern Iraq, were studied and interpreted for updating the structural picture of the major Mishrif Formation for the reservoir in the field. The Mishrif Formation is rich in petroleum in this area, with an area covering about 820 km2. The horizon was calibrated and defined on the seismic section with well logs data (well tops, check shot, sonic logs, and density logs) in the interpretation process to identify the upper and lower boundaries of the Formation.  Seismic attributes were used to study the formation, including instantaneous phase attributes and relative acoustic impedance on time slice of 3D seismic data . Also, relative acoustic impedance was utilized to study the top of the Mishrif Formation. Based on these seismic attributes, karst features of the formation were identified. In addition, the nature of the lithology in the study area and the change in porosity were determined through the relative acoustic impedance The overlap of the top of the Mishrif Formation with the bottom of the Khasib Formation was determined because the Mishrif Formation is considered as an unconformity surface.

scholarly journals Development and Feasibility of a Kinect-Based Constraint-Induced Therapy Program in the Home Setting for Children With Unilateral Cerebral Palsy

2021 ◽  
Vol 9 ◽  
Author(s):  
Hao-Ling Chen ◽  
Szu-Yu Lin ◽  
Chun-Fu Yeh ◽  
Ren-Yu Chen ◽  
Hsien-Hui Tang ◽  
...  
Keyword(s):  
Cerebral Palsy ◽  
Phase 1 ◽  
Training System ◽  
Phase 2 ◽  
Two Phase ◽  
Clinical Trial Registration ◽  
Home Setting ◽  
Therapy Program ◽  
Phase Study ◽  
Block Test

Introduction: Cerebral palsy (CP) is the leading cause of childhood-onset physical disability. Children with CP often have impaired upper limb (UL) function. Constraint-induced therapy (CIT) is one of the most effective UL interventions for children with unilateral CP. However, concerns about CIT for children have been repeatedly raised due to frustration caused by restraint of the child’s less-affected UL and lack of motivation for the intensive protocol. Virtual reality (VR), which can mitigate the disadvantages of CIT, potentially can be used as an alternative mediator for implementing CIT. Therefore, we developed a VR-based CIT program for children with CP using the Kinect system.Aims: The feasibility of the Kinect-based CIT program was evaluated for children with unilateral CP using a two-phase study design.Materials and Methods: In phase 1, ten children with unilateral CP were recruited. To confirm the achievement of the motor training goals, maximal UL joint angles were evaluated during gameplay. To evaluate children’s perceptions of the game, a questionnaire was used. In phase 2, eight children with unilateral CP were recruited and received an 8 weeks Kinect-based CIT intervention. Performance scores of the game and outcomes of the box and block test (BBT) were recorded weekly.Results: In phase 1, results supported that the design of the program was CIT-specific and was motivational for children with unilateral CP. In phase 2, game performance and the BBT scores began showing stable improvements in the fifth week of intervention.Conclusion: It suggested the Kinect-based CIT program was beneficial to the motor function of the affected UL for children with unilateral CP. According to the results of this feasibility study, larger and controlled effectiveness studies of the Kinect-based CIT program can be conducted to further improve its clinical utility.Clinical Trial Registration: ClinicalTrials.gov, NCT02808195; Comparative effectiveness of a Kinect-based unilateral arm training system vs. CIT for children with CP

scholarly journals Texting Older Sisters to Step: The TOSS Study

2018 ◽  
Vol 41 (3) ◽  
pp. 388-408 ◽  
Author(s):  
Pamela G. Bowen ◽  
Olivio J. Clay ◽  
Loretta T. Lee ◽  
Wesley Browning ◽  
Yu-Mei Schoenberger ◽  
...  
Keyword(s):  
Physical Activity ◽  
African American Women ◽  
Phase 1 ◽  
Text Messages ◽  
Phase 2 ◽  
Two Phase ◽  
Contemplation Stage ◽  
Phase Study ◽  
Older African American Women ◽  
The Mean

The purpose of our two-phase study was to develop acceptable text messages to increase physical activity. Four focus groups (two for each phase) were conducted with older African American women who had access to texting-capable mobile phones and were in the contemplation stage for physical activity. The mean age of Phase 1 participants ( n = 12) was 71 and ranged from 65 to 86 years. Content analysis was used to identify fundamental themes that were later used to develop text messages. Six categories emerged from the data and 31 text messages were developed based on focus group input and national recommendations. The mean age of Phase 2 participants ( n = 9) was 67 and ranged from 65 to 75 years. Descriptive statistics revealed 100% of participants understood all messages. When messages were evaluated individually, a minimum of 78% felt each message motivated activity and 67% said lengths were perfect. Findings identified messages that were relevant and potentially motivational to stimulate physical activity among this population.

THE G-LOG* SEISMIC INVERSION PROCESS

1981 ◽  
Vol 21 (1) ◽  
pp. 155
Author(s):  
D. B. Hays ◽  
J. Wardell
Keyword(s):  
Wave Equation ◽  
Seismic Data ◽  
Acoustic Impedance ◽  
Mean Squared Error ◽  
Seismic Inversion ◽  
Synthetic Seismogram ◽  
Inversion Method ◽  
Multiple Reflections ◽  
Seismic Section ◽  
Impedance Model

The G-LOG process is a method of seismic inversion which provides direct estimates of subsurface acoustic impedance from wavelet process stacked or migrated data. The fundamentals and characteristics of the inversion method will be discussed and examples of its use on Australian seismic data will be presented.G-LOG functions are derived by an iterative subsurface modelling technique based on a rigorous inversion of one- dimensional wave equation. This process finds the acoustic impedance model, or log, whose resulting wave-equation- consistent synthetic seismogram best matches the input seismic data in a least mean squared error sense. Multiple reflections are included in the synthetic seismogram, so that they become useful information in the determination of the log.Interval velocity logs are derived from the acoustic impedance logs. The results can be displayed in various forms, including detailed velocity logs, and colour-coded log 'sections' to match with the seismic section. Several examples of such results are presented.The G-LOG process is a revolutionary technique of subsurface modelling, and the logs it provides are strong indicators of subsurface lithology and will be an important tool in the evaluation and re-evaluation of potential hydrocarbon-bearing prospects.*Trademark of G.S.I.

Establishment of a Disaster-Related Psychological Screening Test

2003 ◽  
Vol 37 (1) ◽  
pp. 97-103 ◽  
Author(s):  
Frank Huang-Chih Chou ◽  
Tom Tung-Ping Su ◽  
Wen-Chen Ou-Yang ◽  
I-Chia Chien ◽  
Ming-Kun Lu ◽  
...  
Keyword(s):  
Screening Test ◽  
Phase 1 ◽  
Rapid Screening ◽  
Operating Characteristics ◽  
Symptom Scale ◽  
Two Phase ◽  
Psychological Screening ◽  
Phase Study ◽  
Long Term Follow Up ◽  
Subset Regression

Objective: To create a short screening scale for the detection of posttraumatic stress disorder (PTSD) and major depressive disorder (MDE) in earthquake survivors in Taiwan. Method: Trained research assistants used the Disaster-Related Psychological Screening Test (DRPST) to assess 461 residents of a village that had experienced a major earthquake. The participants were also evaluated by psychiatrists using the Mini-International Neuropsychiatric Interview (MINI). Best subset regression analysis and the receiver operating characteristics curve were used to select a subset of items and cut-off points from the DRPST. Results: A seven-symptom scale and a three-symptom analogue were selected for PTSD and MDE screening, respectively. Scores of three or more on the PTSD scale and two or more on the MDE scale were used to define a group of positive cases that provide useful information for the patient cohort and will be valuable in long-term follow-up studies of the prevalence of psychiatric diseases following a natural disaster. However, higher scores could also be used to define positive cases under limited psychiatric care resources. Conclusion: The DRPST, which was administered for phase 1 of this two-phase study, may be used for effective and rapid screening for PTSD and MDE after an earthquake, despite the usual limitations on resources following a disaster.

Nonbright‐spot AVO: Two examples

Geophysics ◽  
1995 ◽  
Vol 60 (5) ◽  
pp. 1398-1408 ◽  
Author(s):  
Christopher P. Ross ◽  
Daniel L. Kinman
Keyword(s):  
Seismic Data ◽  
Acoustic Impedance ◽  
Normal Incidence ◽  
Bright Spot ◽  
Seismic Section ◽  
Amplitude Variation With Offset ◽  
Avo Analysis ◽  
Impedance Contrast ◽  
Seismic Anomalies ◽  
Low Amplitude

The use of amplitude variation with offset (AVO) attribute sections such as the product of the normal incidence trace (A) and the gradient trace (B) have been used extensively in bright spot AVO analysis and interpretation. However, while these sections have often worked well with low acoustic impedance bright spot responses, they are not reliable indicators of nonbright‐spot seismic anomalies. Analyzing nonbright‐spot seismic data with common AVO attribute sections will: (1) not detect the gas‐charged reservoir because of near‐zero acoustic impedance contrast between the sands and encasing shales, or (2) yield an incorrect (negative) AVO product if the normal incidence and gradient values are opposite in sign. We divide nonbright‐spot AVO offset responses into two subcategories: those with phase reversals and those without. An AVO analysis procedure for these anomalies is presented through two examples. The procedure exploits the nature of the prestack response, yielding a more definitive AVO attribute section, and this technique is adaptive to both subcategories of nonbright‐spot AVO responses. This technique identifies the presence of gas‐charged pore fluids within the reservoir when compared to a conventionally processed, relative amplitude seismic section with characteristically low amplitude responses for near‐zero acoustic impedance contrast sands.

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