scholarly journals The method of pneumoperitoneum in the diagnosis and determination of the operability of cancer of the upper stomach

2021 ◽  
Vol 43 (2) ◽  
pp. 18-24
Author(s):  
E. G. Kucherkov
Keyword(s):  
Large Percentage ◽  
Surrounding Tissue

Although radical operations for cancer of the upper part of the stomach have become widespread, a large percentage of operations for such lesions ends with a trial laparotomy due to the extensive spread of the tumor to the surrounding tissue organs, which has not been clarified before the operation.

The effect of transection of the duck blastoderm on the orientation of the embryo

Development ◽  
1968 ◽  
Vol 20 (3) ◽  
pp. 237-245
Author(s):  
Teresa Rogulska
Keyword(s):  
Large Percentage ◽  
Control Material ◽  
Extensive Information

Von Baer (1828) formulated a rule according to which the cephalo-caudal axis is perpendicular to the long axis of the shell, and the head of the embryo is directed forwards when the egg is placed with the blunt end to the left. This law has been checked in several species of bird: hen, duck, pigeon, goose, turkey (see Clavert, 1960, for references) and quail (Fargeix, 1963, 1964). Embryos obeying von Baer's rule were found to constitute the most numerous class, but considerable interspecific as well as intraspecific differences were observed. The studies by Lutz (1949) supply extensive information on the regulative capacities of the duck blastoderm, but do not provide any data concerning the determination of the presumptive axis of the blastoderm. The control material of this author revealed a large percentage of embryos obeying von Baer's rule. In consequence Lutz defines transections perpendicular to the long axis of the shell as ‘parallel to the presumptive axis’, and transections parallel to the long axis as ‘perpendicular to the presumptive axis’.

scholarly journals Influence of Glucose Supply and Demand on Determination of Brain Glucose Content with Labeled Methylglucose

1996 ◽  
Vol 16 (3) ◽  
pp. 439-449 ◽  
Author(s):  
Hajime Nakanishi ◽  
Nancy F. Cruz ◽  
Keiji Adachi ◽  
Louis Sokoloff ◽  
Gerald A. Dienel
Keyword(s):  
Glucose Level ◽  
Distribution Ratio ◽  
Plasma Glucose ◽  
Glucose Concentration ◽  
Surrounding Tissue ◽  
Metabolic Demand ◽  
Glucose Content ◽  
Brain Glucose ◽  
Glucose Levels

The equilibrium brain/plasma distribution ratio for 3- O-methyl-D-glucose (methylglucose) varies with plasma and tissue glucose contents and can be used to determine local glucose levels in brain. This ratio was previously found to rise as brain glucose concentration fell in response to lowered plasma glucose content. The ratios, however, differed with the same tissue glucose levels in conscious and pentobarbital-sedated rats, suggesting that changes in metabolic demand might alter the quantitative relationship between the methylglucose distribution ratio and brain glucose concentration. To examine this possibility, metabolic rate was varied by focal drug application, and hexose concentrations measured in treated and surrounding tissue. When tissue glucose levels were reduced by raised metabolic demand, methylglucose distribution ratios also fell. When brain glucose levels rose due to reduced consumption, the methylglucose distribution ratio also rose. Thus, in contrast to the inverse relationship between brain/plasma methylglucose ratio and brain glucose concentration when brain glucose content is altered secondarily to changes in plasma glucose level, changes in brain glucose content induced by altered glucose utilization cause the brain glucose level and methylglucose distribution ratio to rise and fall in a direct relationship. Determination of brain glucose content from methylglucose distribution ratios must take into account rates of glucose delivery and consumption.

Intravascular oxygen distribution in subcutaneous 9L tumors and radiation sensitivity

1997 ◽  
Vol 82 (6) ◽  
pp. 1939-1945 ◽  
Author(s):  
George J. Cerniglia ◽  
David F. Wilson ◽  
Marek Pawlowski ◽  
Sergei Vinogradov ◽  
John Biaglow
Keyword(s):  
Tumor Vasculature ◽  
Radiation Sensitivity ◽  
Surrounding Tissue ◽  
Oxygen Distribution ◽  
Tissue Oxygen ◽  
Phosphorescence Quenching ◽  
Tumor Identification ◽  
Oxygen Measurements

Cerniglia, George J., David F. Wilson, Marek Pawlowski, Sergei Vinogradov, and John Biaglow. Intravascular oxygen distribution in subcutaneous 9L tumors and radiation sensitivity. J. Appl. Physiol. 82(6): 1939–1945, 1997.—Phosphorescence quenching was evaluated as a technique for measuring [Formula: see text] in tumors and for determining the effect of increased[Formula: see text] on sensitivity of the tumors to radiation. Suspensions of cultured 9L cells or small pieces of solid tumors from 9L cells were injected subcutaneously on the hindquarter of rats, and tumors were grown to between 0.2 and 1.0 cm in diameter. Oxygen-dependent quenching of the phosphorescence of intravenously injected Pd-meso-tetra-(4-carboxyphenyl) porphine was used to image the in vivo distribution of [Formula: see text] in the vasculature of small tumors and surrounding tissue. Maps (512 × 480 pixels) of tissue oxygen distribution showed that the[Formula: see text] within 9L tumors was low (2–12 Torr) relative to the surrounding muscle tissue (20–40 Torr). When the rats were given 100% oxygen or carbogen (95% O2-5% CO2) to breathe, the[Formula: see text] in the tumors increased significantly. This increase was variable among tumors and was greater with carbogen compared with 100% oxygen. Based on irradiation and regrowth studies, carbogen breathing increased the sensitivity of the tumors to radiation. This is consistent with the measured increase in[Formula: see text] in the tumor vasculature. It is concluded that phosphorescence quenching can be used for noninvasive determination of the oxygenation of tumors. This method for oxygen measurements has great potential for clinical application in tumor identification and therapy.

scholarly journals Thermo-mechanical stresses distribution on bone drilling: Numerical and experimental procedures

2017 ◽  
Vol 233 (4) ◽  
pp. 637-646 ◽  
Author(s):  
Maria G Fernandes ◽  
Elza M Fonseca ◽  
Renato N Jorge
Keyword(s):  
Numerical Model ◽  
Bone Tissue ◽  
Experimental Tests ◽  
Mechanical Stresses ◽  
Surrounding Tissue ◽  
Drilling Process ◽  
Bone Drilling ◽  
Drilling Parameters ◽  
Drilling Conditions

In bone drilling, the temperature and the level of stresses at the bone tissue are function of the drilling parameters. If certain thresholds are exceeded, irreversible damages may occur on the bone tissue. One of the main challenges in the drilling process is to control the associated parameters and even more important, to avoid the surrounding tissue damage. In this study, a dynamic numerical model is developed to determine the thermo-mechanical stresses generated during the bone drilling, using the finite element method. The numerical model incorporates the geometric and dynamic characteristics involved in the drilling processes, as well the developed temperature inside the material. The numerical analysis has been validated by experimental tests using polyurethane foam materials with similar mechanical properties to the human bone. Results suggest that a drill bit with lower drill speed and higher feed rate can reduce the strains and stresses in bone during the drilling process. The proposed numerical model reflected adequately the experimental results and could be useful in determination of optimal drilling conditions that minimise the bone injuries.

Investigation of the Thermal Conductivity of Rubber

1938 ◽  
Vol 11 (2) ◽  
pp. 359-371 ◽  
Author(s):  
L. Frumkin ◽  
Yu Dubinker
Keyword(s):  
Thermal Conductivity ◽  
Zinc Oxide ◽  
Carbon Black ◽  
Natural Rubber ◽  
Considerable Increase ◽  
Large Percentage ◽  
K Value ◽  
Synthetic Rubber ◽  
Coefficient Of Thermal Conductivity

Abstract 1. The apparatus for the determination of the coefficients of thermal conductivity which is described is satisfactory for the investigation of rubber mixtures. 2. A review of the results of the determinations of K values of various mixtures leads to the following conclusions: (a) The thermal conductivity of rubber mixtures containing synthetic rubber is greater than that of mixtures containing natural rubber. (b) The addition of zinc oxide even in considerable quantities to rubber mixtures containing a large percentage (55 per cent) of carbon black does not substantially increase thermal conductivity. (c) In the case of carcass mixtures a considerable increase in the coefficient of thermal conductivity is observed when the content of zinc oxide is increased from 7.5 to 15 per cent by weight; on further increase in the zinc oxide K increases but little. (d) The K value of carcass mixtures before vulcanization is smaller than that of the same mixtures after vulcanization by an average of 23 per cent. (e) The thermal conductivity of uncured tread mixtures is the same as that of vulcanized mixtures. (f) The coefficient of vulcanization has no effect on the K value of unloaded mixtures and mixtures containing fillers. (g) The K value of rubber mixtures increases sharply with addition up to 60 per cent by volume of fillers with good thermal conductivity (zinc oxide and graphite), but only slowly with the addition of fillers of medium thermal conductivity (carbon black). In other words, the curve of the relation between the coefficient of thermal conductivity and the percentage by volume of graphite and of zinc oxide is convex to the filler axis and is concave in the case of carbon black.

Joint petrophysical inversion of electromagnetic and full-waveform seismic data

Geophysics ◽  
2012 ◽  
Vol 77 (3) ◽  
pp. WA3-WA18 ◽  
Author(s):  
Guozhong Gao ◽  
Aria Abubakar ◽  
Tarek M. Habashy
Keyword(s):  
Bulk Modulus ◽  
Seismic Data ◽  
Joint Inversion ◽  
Large Percentage ◽  
Rock Matrix ◽  
Petrophysical Parameters ◽  
Electromagnetic Data ◽  
Full Waveform ◽  
Fluid Saturation

Accurate determination of reservoir petrophysical parameters is of great importance for reservoir monitoring and characterization. We developed a joint inversion approach for the direct estimation of in situ reservoir petrophysical parameters such as porosity and fluid saturations by jointly inverting electromagnetic and full-waveform seismic measurements. Full-waveform seismic inversions allow the exploitation of the full content of the data so that a more accurate geophysical model can be inferred. Electromagnetic data are linked to porosity and fluid saturations through Archie’s equations, whereas seismic data are linked to them through rock-physics fluid-substitution equations. For seismic modeling, we used an acoustic approximation. Sensitivity studies combined with inversion tests show that seismic data are mainly sensitive to porosity distribution, whereas electromagnetic data are more sensitive to fluid-saturation distribution. The separate inversion of electromagnetic or seismic data is highly nonunique and thus leads to great ambiguity in the determination of porosity and fluid saturations. In our approach, we used a Gauss-Newton algorithm equipped with the multiplicative regularization and proper data-weighting scheme. We tested the implemented joint petrophysical inversion method using various synthetic models for surface and crosswell measurements. We found that the joint inversion approach provides substantial advantage for an improved estimation of porosity and fluid-saturation distributions over the one obtained from the separate inversion of electromagnetic and seismic data. This advantage is achieved by significantly reducing the ambiguity on the determination of porosity and fluid saturations using multiphysics measurements. We also carried out a study on the effects of using inaccurate petrophysical transform parameters on the inversion results. Our study demonstrated that up to 20% errors in the saturation and porosity exponents in Archie’s equations do not cause significant errors in the inversion results. On the other hand, if the bulk modulus and density of the rock matrix have a large percentage of errors (i.e., more than 5%), the inversion results will be significantly degraded. However, if the density of the rock matrix has an error of less than 2%, the joint inversion can tolerate a large percentage of errors in the bulk modulus of the rock matrix.

scholarly journals DNA-based determination of suitable pollinating cultivars for the pear cultivar 'Carola' (Pyrus communis)

2007 ◽  
Vol 13 (1) ◽  
Author(s):  
H. Nybom ◽  
J. Sehic ◽  
H. Mattisson
Keyword(s):  
Fruit Set ◽  
Large Percentage ◽  
Maximum Distance ◽  
Pollen Transfer ◽  
Long Distance ◽  
Maternal Parent ◽  
Pear Cultivar ◽  
Pear Orchard ◽  
S Allele

Pollen-limited fruit set has long been suspected in some relatively low-yielding orchards with the Swedish pear cultivar 'Carola'. Fruit was therefore harvested on 23 'Carola' trees in a commercial pear orchard. The seeds were germinated and five seedlings from each tree were sampled to determine which of the surrounding cultivars had been the most successful pollinators. Leaves of 'Carola', the 7 putative pollinating cultivars and the 115 seedlings were analysed with 6 RAPD primers. By comparison of the band patterns, paternity could be ascertained for 74 seedlings. The by far most successful pollinator was 'Clara Frijs' which had sired approx. half of the seedlings, followed by 'Herzogin Elsa', `Skanskt Sockerpiiron', 'Alexandre Lucas', 'Coloree de Juillet' and 'Doyenne du Cornice'. The latter is the maternal parent of 'Carola', and these two cultivars must therefore share one S-allele and hence can only be semi-compatible. In addition, 6% of the seedlings were in all likelihood derived from selling_ since they showed no bands that did not occur also in 'Carola'. Maximum distance between 'Carola' trees and suitable pollinators should not exceed 15-20 tn. Longer distances may produce a serious dearth of compatible pol­len as evidenced by the large percentage of seedlings derived either from selling. (25%) or from long-distance (> 40 m) pollen transfer (25%) when 'Carola' trees were surrounded by non-preferred pollinators.

scholarly journals Ti(C, N) as Barrier Coatings

Coatings ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 432 ◽  
Author(s):  
Katarzyna Banaszek ◽  
Leszek Klimek
Keyword(s):  
Precious Metal ◽  
Biomedical Applications ◽  
Protective Coatings ◽  
Artificial Saliva ◽  
Corrosion Process ◽  
The Body ◽  
Metal Alloys ◽  
Surrounding Tissue ◽  
Barrier Coatings

Metals and their alloys are materials that have long been used in stomatological prosthetics and orthodontics. The side effects of their application include reactions of the body such as allergies. Their source can be corrosion products as well as metal ions released in the corrosion process, which penetrate the surrounding tissue. In order to prevent the harming effect of metal alloys, intensive research has been performed to purify metal prosthetic restorations by way of modifying their surface. The study presents the investigation results of Ti(C, N)-type coatings applied to alloy Ni–Cr by means of the magnetronic method. Five coatings differing in the nitrogen and carbon content were investigated. The studies included the determination of the coatings’ chemical composition, construction, as well as the amount of ions released into the environment: distilled water, 0.9% NaCl and artificial saliva. The performed investigations showed that, in reference to an alloy without a coating, each coating constitutes a barrier reducing the amount of ions transferred into the examined solutions. So, Ti(C, N)-type coatings can be considered for biomedical applications as protective coatings of non-precious metal alloys.

scholarly journals Failure and failure mechanisms of wood during longitudinal compression monitored by synchrotron micro-computed tomography

Holzforschung ◽  
2016 ◽  
Vol 70 (2) ◽  
pp. 179-185 ◽  
Author(s):  
Michaela Zauner ◽  
Marco Stampanoni ◽  
Peter Niemz
Keyword(s):  
Computed Tomography ◽  
Plastic Deformation ◽  
Uniaxial Compression ◽  
Failure Mechanisms ◽  
Surrounding Tissue ◽  
Micro Computed Tomography ◽  
Longitudinal Compression ◽  
Spruce Wood

Abstract The lasting plastic deformation of the cellular elements of beech, fir, and spruce wood under uniaxial compression has been investigated by the combination of in situ loading and synchrotron micro-computed tomography. The deformation of singular elements embedded in the tissue and their influence on the deformation lines and surrounding tissue was examined by tomographic reconstructions. An automatic observation of the failure area was applied in the case of the softwoods, which permitted the determination of the densification degree. The development of failure lines differed from the expected pattern by often showing branching. However, the 3D observations confirmed the effects known from 2D examinations in many cases.

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