scholarly journals Difference picture algorithms for the analysis of extracellular components of histological images.

1985 ◽  
Vol 33 (4) ◽  
pp. 261-267 ◽  
Author(s):  
T F Knoll ◽  
L L Brinkley ◽  
E J Delp

A computer-assisted method for objectively identifying and displaying the distribution of molecules that can only be positively identified by a combination of staining characteristics and susceptibility to specific enzymatic digestion or chemical degradation is presented. The visual image of an enzymatically digested tissue section is subtracted from that of an adjacent buffer-incubated control section and the distribution of the extracellular molecules removed from the tissue section displayed. Photomicrographs are taken using white light and narrow bandwidth filters of wavelengths at or near the maximum absorbance for the dye products used to visualize the extracellular matrix and cells. Each negative is standardized using reference gray levels. The cell and matrix images of both digested and undigested sections are then registered. The locations of cells in both control and digested sections are identified and set to an undefined gray level value in the matrix images. The cell-removed images of the control and digested sections are then registered and the difference in gray levels between the two images calculated and displayed. The validity of results obtained is primarily dependent on the soundness of the histological visualization and digestion techniques used, but is independent of investigator interpretation.

1981 ◽  
Vol 29 (4) ◽  
pp. 25

CAPS. The Computer Assisted Problem Solving (CAPS) Project is in its second year of development in the Rochester (Minnesota) Public Schools. The primary goal of CAPS is to provide elementary school students (K-6) with opportunities to practice the skills involved in problem solving in order to improve their confidence and competence as problem solvers. In the first year of the project, the staff reviewed learning theory and problem-solving research in order to develop a problem-solving skill matrix. The matrix includes problem-solving techniques and aids in the areas of memory, cognitive skills, cognitive control strategies, and creativity. The major focus of the project this year is to develop and field test computer software and classroom activities in the area of memory. Inservice training will also be prepared for teachers with an emphasis on recognizing the difference between problem-solving exercises (practice) and novel problems (true problem solving). CAPS is funded by Title IV-C. For more information contact Donna Stanger, Project Director CAPS, Rochester Public Schools, 903 West Center, Rochester, MN 55901.


Author(s):  
R.A. Herring

Rapid thermal annealing (RTA) of ion-implanted Si is important for device fabrication. The defect structures of 2.5, 4.0, and 6.0 MeV As-implanted silicon irradiated to fluences of 2E14, 4E14, and 6E14, respectively, have been analyzed by electron diffraction both before and after RTA at 1100°C for 10 seconds. At such high fluences and energies the implanted As ions change the Si from crystalline to amorphous. Three distinct amorphous regions emerge due to the three implantation energies used (Fig. 1). The amorphous regions are separated from each other by crystalline Si (marked L1, L2, and L3 in Fig. 1) which contains a high concentration of small defect clusters. The small defect clusters were similar to what had been determined earlier as being amorphous zones since their contrast was principally of the structure-factor type that arises due to the difference in extinction distance between the matrix and damage regions.


Author(s):  
P B Parejiya ◽  
B S Barot ◽  
P K Shelat

The present study was carried out to fabricate a prolonged design for tramadol using Kollidon SR (Polyvinyl acetate and povidone based matrix retarding polymer). Matrix tablet formulations were prepared by direct compression of Kollidon SR of a varying proportion with a fixed percentage of tramadol. Tablets containing a 1:0.5 (Drug: Kollidon SR) ratio exhibited a rapid rate of drug release with an initial burst effect. Incorporation of more Kollidon SR in the matrix tablet extended the release of drug with subsequent minimization of the burst effect as confirmed by the mean dissolution time, dissolution efficiency and f2 value. Among the formulation batches, a direct relationship was obtained between release rate and the percentage of Kollidon SR used. The formulation showed close resemblance to the commercial product Contramal and compliance with USP specification. The results were explored and explained by the difference of micromeritic characteristics of the polymers and blend of drug with excipients. Insignificant effects of various factors, e.g. pH of dissolution media, ionic strength, speed of paddle were found on the drug release from Kollidon-SR matrix. The formulation followed the Higuchi kinetic model of drug release. Stability study data indicated stable character of Batch T6 after short-term stability study.


2018 ◽  
Vol 146 (12) ◽  
pp. 3949-3976 ◽  
Author(s):  
Herschel L. Mitchell ◽  
P. L. Houtekamer ◽  
Sylvain Heilliette

Abstract A column EnKF, based on the Canadian global EnKF and using the RTTOV radiative transfer (RT) model, is employed to investigate issues relating to the EnKF assimilation of Advanced Microwave Sounding Unit-A (AMSU-A) radiance measurements. Experiments are performed with large and small ensembles, with and without localization. Three different descriptions of background temperature error are considered: 1) using analytical vertical modes and hypothetical spectra, 2) using the vertical modes and spectrum of a covariance matrix obtained from the global EnKF after 2 weeks of cycling, and 3) using the vertical modes and spectrum of the static background error covariance matrix employed to initiate a global data assimilation cycle. It is found that the EnKF performs well in some of the experiments with background error description 1, and yields modest error reductions with background error description 3. However, the EnKF is virtually unable to reduce the background error (even when using a large ensemble) with background error description 2. To analyze these results, the different background error descriptions are viewed through the prism of the RT model by comparing the trace of the matrix , where is the RT model and is the background error covariance matrix. Indeed, this comparison is found to explain the difference in the results obtained, which relates to the degree to which deep modes are, or are not, present in the different background error covariances. The results suggest that, after 2 weeks of cycling, the global EnKF has virtually eliminated all background error structures that can be “seen” by the AMSU-A radiances.


1894 ◽  
Vol 1 (11) ◽  
pp. 496-499
Author(s):  
Henry H. Howorth

Mr. Deeley tells your readers that he has recently been to the summit of Mont Blanc, and has been studying the difference between névé and glacier ice. This is interesting; but we thought that a great many people had done the same thing during the last hundred years, and we thought that one of them, Forbes, had studied the famous Mountain and the phenomenoninquestion to good effect, not in a casual visit to the Alps, but in the course of many years of patient labour. Among other things we also thought he had shown that in a viscous body like ice, the slope of the upper surface necessary to make it begin to move is the same as the slope which, would be required to induce motion in the ice if its bed were inclined at an angle. He further collected considerable evidence to show what the least angle is upon which ice will begin to move. This is the slope, the least slope, available. It is nothing less than astounding to me that anyone should venture to postulate a Scand in avian ice-sheet in the North Sea until he had considered this necessary factor, and how it would operate.The Scand in avian ice-sheet was, I believe, the invention of Croll, who, sittinginhis arm-chair and endowed with a brilliant imagination, imposed upon sober science this extraordinary postulate. He did not dream of testing it by an examination of the coasts of Norway, or even of Britain, but put it forward apparently as a magnificent deduction. All deductions untested by experiment are dangerous. Thus it came about that the great monster which is said to have come from Norway, goodness knows by what mechanical process, speedily dissolved away on the application of inductive methods. Of course it still maintained its hold upon that section, of geologists who dogmatiseinprint a great deal about the Glacial period before they have ever seen a glacier at work at all; but I am speaking of those who have studied the problem inductively. First Mr. James Geikie, a disciple of Croll, was obliged to confess that this ice-sheet, which is actually said to have advanced as far as the hundred-fathom line in the Atlantic, and there presented a cliff of ice like the Antarctic continent, never can have reached the Faroes, which had an ice-sheet of their own. Next Messrs. Peach and Home were constrained to admit that no traces of it of any kind occur in the Orkneys, or in Eastern Scotland. They still maintained its presence in the Shetlands; however, this was upon evidence which is somewhat extraordinary. I do not mean the evidence as to the direction of the striation, which was so roughly handled by Mr. Milne-Home, but I mean the evidence they adduce that the boulders found on the islands are apparently all local ones, and that, contrary to the deposits of glaciers, they diminish in number as we recede from the matrix whence they were derived.


Telematika ◽  
2020 ◽  
Vol 17 (1) ◽  
pp. 26
Author(s):  
Afif Irfan Abdurrahman ◽  
Bambang Yuwono ◽  
Yuli Fauziah

Flood disaster is a dangerous disaster, an event that occurs due to overflow of water resulting in submerged land is called a flood disaster. Almost every year Bantul Regency is affected by floods due to high rainfall. The flood disaster that struck in Bantul Regency made the Bantul District Disaster Management Agency (BPBD) difficult to handle so that it needed a mapping of the level of the impact of the flood disaster to minimize the occurrence of floods and provide information to the public.This study will create a system to map the level of impact of floods in Bantul Regency with a decision support method namely Multi Attribute Utility Theory (MAUT). The MAUT method stage in determining the level of impact of flood disasters through the process of normalization and matrix multiplication. The method helps in determining the areas affected by floods, by managing the Indonesian Disaster Information Data (DIBI). The data managed is data on criteria for the death toll, lost victims, damage to houses, damage to public facilities, and damage to roads. Each criteria data has a value that can be used to determine the level of impact of a flood disaster. The stages for determining the level of impact of a disaster require a weighting calculation process. The results of the weighting process display the scoring value which has a value of 1 = low, 2 = moderate, 3 = high. To assist in determining the affected areas using the matrix normalization and multiplication process the process is the application of the Multi Attribute Utility Theory (MAUT) method.This study resulted in a mapping of the level of impact displayed on google maps. The map view shows the affected area points and the level of impact of the flood disaster in Bantul Regency. The mapping produced from the DIBI data in 2017 produced the highest affected area in the Imogiri sub-district. The results of testing the data can be concluded that the results of this study have an accuracy rate of 95% when compared with the results of the mapping previously carried out by BPBD Bantul Regency. The difference in the level of accuracy is because the criteria data used are not the same as the criteria data used by BPBD in Bantul Regency so that the accuracy rate is 95%.


Author(s):  
T. A. Akhmetov ◽  
V. K. Merinov ◽  
N. V. Kargapolova

The possibility of using the deposited suspended particles of electric arc furnaces as heat-resistant modifying additives for friction composites is considered. It is shown that the precipitated particles obtained during the smelting of steel of different grades have identical morphology and are a homogeneous mechanical mixture consisting mainly of spherical particles of no more than 1 µm in size.It is established that the composites on the basis of the fluoropolymer, modified by precipitated particles obtained in the smelting of steel of various sizes have different tribological properties. This is due to the difference in the chemical composition of the deposited particles.It was found that the use of deposited particles in composite materials allows to vary the value of the dynamic friction coefficient in a wider range, in particular to obtain higher and stable values, while the wear resistance of modified friction composites is more than 500 times higher than the same index of the matrix polymer – polytetrafluoroethylene.


Author(s):  
I.V. Frolov ◽  
◽  
V.A. Sergeev ◽  
A.M. Hodakov ◽  
S.A. Zaytsev ◽  
...  

The paper presents the results of studies of changes in the characteristics of LED COB matrices of the GW P9LR31.EM - DURIS S 8 type as part of a LED luminaire when tested under the direct current in a continuous mode and in an electrocycling mode. The arrays consist of eight InGaN/GaN LED dies connected in series, coated with a phosphor. Calculation in the Comsol Multiphtsics environment of the temperature field of the luminaire at the rated operating current and free convection heat transfer showed that the maximum overheating of the matrices does not exceed 46 K, and the difference in their temperatures is 2 K. At the same time, the experimental values of the thermal resistances of the matrices of a real lamp vary from 42 to 58 K/W. Before testing, the I-V characteristics of the matrices differ markedly in the level of leakage current in the voltage range from 14 V to 19 V, and the LEDs in the luminaire matrices have a significant spread in the brightness of emission in the microcurrent mode. The degree of this scatter within each matrix was estimated by measuring the luminescence brightness of each die of the matrix and calculating the coefficient of variation γ. It was found that the coefficient of variation of the emission brightness of the COB matrix dies measured at a current of 100 nA strongly correlates with the leakage current. When testing a luminaire under the direct current, the most significant changes in the electrophysical and optical characteristics of COB matrices are observed in the range of microcurrents: the distribution of the emission brightness of the matrix dies at a current of 100 nA becomes more uniform. The greatest changes in matrix characteristics were observed after the first 700 hours of testing, that is, at the running-in stage. At the same time, no correlation was found between the degree of change in the characteristics of the matrices during tests and their thermal resistances.


2021 ◽  
Vol 11 ◽  
Author(s):  
Henriette L. Möllmann ◽  
Laura Apeltrath ◽  
Nadia Karnatz ◽  
Max Wilkat ◽  
Erik Riedel ◽  
...  

ObjectivesThis retrospective study compared two mandibular reconstruction procedures—conventional reconstruction plates (CR) and patient-specific implants (PSI)—and evaluated their accuracy of reconstruction and clinical outcome.MethodsOverall, 94 patients had undergone mandibular reconstruction with CR (n = 48) and PSI (n = 46). Six detectable and replicable anatomical reference points, identified via computer tomography, were used for defining the mandibular dimensions. The accuracy of reconstruction was assessed using pre- and postoperative differences.ResultsIn the CR group, the largest difference was at the lateral point of the condyle mandibulae (D2) -1.56 mm (SD = 3.8). In the PSI group, the largest difference between preoperative and postoperative measurement was shown at the processus coronoid (D5) with +1.86 mm (SD = 6.0). Significant differences within the groups in pre- and postoperative measurements were identified at the gonion (D6) [t(56) = -2.217; p = .031 <.05]. In the CR group, the difference was 1.5 (SD = 3.9) and in the PSI group -1.04 (SD = 4.9). CR did not demonstrate a higher risk of plate fractures and post-operative complications compared to PSI.ConclusionFor reconstructing mandibular defects, CR and PSI are eligible. In each case, the advantages and disadvantages of these approaches must be assessed. The functional and esthetic outcome of mandibular reconstruction significantly improves with the experience of the surgeon in conducting microvascular grafts and familiarity with computer-assisted surgery. Interoperator variability can be reduced, and training of younger surgeons involved in planning can be reaching better outcomes in the future.


2021 ◽  
Vol 98 (6) ◽  
pp. 5-19
Author(s):  
VL.I. KOLCHUNOV ◽  
◽  
O.I. AL-HASHIMI ◽  
M.V. PROTCHENKO ◽  
◽  
...  

The authors developed a model for single reinforced concrete strips in block wedge and arches between inclined cracks and approximated rectangular cross-sections using small squares in matrix elements. From the analysis of the works of N.I. Karpenko and S.N. Karpenko the "nagel" forces in the longitudinal tensile reinforcement and crack slip , as a function of the opening width and concrete deformations in relation to the cosine of the angle . The experimental " nagel " forces and crack slip dependences for the connection between and in the form of an exponent for the reinforcement deformations and spacing are determined. The forces have been calculated for two to three cross-sections (single composite strips) of reinforced concrete structures. On the bases of accepted hypothesis, a new effect of reinforced concrete and a joint modulus in a strip of composite single local shear zone for the difference of mean relative linear and angular deformations of mutual displacements of concrete (or reinforcement) are developed. The hypothesis allows one to reduce the order of the system of differential equations of Rzhanitsyn and to obtain in each joint the total angular deformations of concrete and the "nagel" effect of reinforcement. The curvature of the composite bars has a relationship from the total bending moment of the bars to the sum of the rigidities. The stiffness physical characteristics of the matrix from the compressed concrete area and the working reinforcement are obtained in a system of equations of equilibrium and deformation, as well as physical equations.


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