Distribution In Positions Research Articles

Detection of olive oil adulteration using principal component analysis applied on total and regio FA content

AbstractPrincipal component analysis (PCA) has been used to establish a new method for the detection of olive oil adulteration. The data set, composed of values obtained from the determination of the mole percentage of total FA and their regiospecific distribution in positions 1 and 3 in TG of oils (pure or mixtures) by GC analysis, was subjected to PCA. 3‐D scatter plots showed clearly that it is possible to distinguish the pure oils from the mixtures. Moreover it is possible to discriminate the different types of seed oil used for the adulteration.

Terrain controls on depressional soil distribution in a hummocky morainal landscape

In hummocky morainal landscapes, soil distribution in well-drained landscape positions tends to follow a consistent pattern. Soils in depressions, however, are more difficult to predict reliably. This study had two objectives: (1) to determine the parent material and landscape properties controlling the formation of the different depressional soils; and (2) to use these controls to identify quantitative, terrain-based predictors of soil type in depressions. Only two terrain attributes, specific dispersal area (SDA) and elevation relative to open water bodies, were required to distinguish three main soil groups: Gley Recharge, Non-gley Recharge, and Discharge soils. Specific dispersal area is the downslope area draining flow from a given grid cell. Gley Recharge soils occur primarily at points with SDA of less than 2 m 2 m −1, regardless of elevation within a given site, because most of the runoff flowing to a point with very low SDA values will pond or infiltrate vertically rather than flow downslope. Non-gley Recharge soils and Discharge soils both occur at points with SDA of greater than 2 m 2 m −1. The majority of the Non-gley Recharge soils occur above 5-m elevation relative to an open water body and the majority of the Discharge soils occur below 5-m elevation relative to an open water body, reflecting the importance of solute cycling in the development of discharge conditions. Buried and depositional soils could not be predicted from current terrain attributes because their profile characteristics were derived from the paleosurface.

Promoting women. Mentoring is a helpful tool not only for helping women to climb the career ladder but also to make men more aware of the specific problems women face.

‘Our chief want in life is someone who will make us do what we can.’—Ralph Waldo Emerson Uta Mackensen ![][1] All human beings are supposedly equal. But by looking at the gender distribution in high‐level management positions in industry, academia and public services, one cannot escape the fact that men seem to be more equal than women. This is not a satisfactory situation, particularly in an economy that depends on well‐trained and educated professionals, who are increasingly in short supply. Numerous strategies are being employed to close the gender gap, either through legislation or through raising awareness and training. Here, we would like to describe our company's experiences with introducing mentoring programmes that aim to increase the number of women in leading positions. This strategy actually works both ways by providing better training for women while acquainting their male superiors with the specific problems faced by the opposite sex. The European Technology Assessment Network report clearly illustrates the situation of women in academia. ‘The status quo [of women in science] is wasteful and inequitable. The abuse of the “old boys’ network” in some of our scientific institutions is an anachronism. The emphasis on gender in hiring and promoting has no place in modern institutions. It is not only bad for science but it denies many women the benefits of a scientific career that are enjoyed by men, such as the satisfaction of curiosity, setting one's own priorities, some status, and a certain degree of autonomy.’ (ETAN report, 2000). The main reason for this unsatisfactory situation is the ‘glass ceiling’, symbolising all invisible structural and cultural barriers that prevent a woman from climbing the career ladder. But women are equally capable of meeting all the requirements a leading position demands, a fact that is supported by numerous studies. In the real … [1]: /embed/graphic-1.gif

Ce, Er, Yb:YCa 4O(BO 3) 3 crystals

The YCa 4O(BO 3) 3 and YCa 4O(BO 3) 3: Yb; Yb and Er; Yb, Er and Ce crystals have been grown by the Czochralski technique. The YCa 4O(BO 3) 3 structure has been investigated by X-ray diffraction study. The refined composition of (Y,Ca)(Ca,Y) 2Ca 2O(BO 3) 3 is (Y 0.792Ca 0.208(6))(Ca 0.938Y 0.062(4)) 2Ca 2O 0.96(2)[ ] 0.04(BO 3) 3 ([ ]-oxygen vacancy). It was found that superstructure reflections with a doubled a-parameter are present for YCa 4O(BO 3) 3 and absent for doped crystals. The known and own structure data of LnCa 4O(BO 3) 3 crystals can be used to obtain a relation between mean interatomic cation–anion distances of (Ln,Ca)(1) and (Ca,Ln)(2) sites and rare-earth (Ln) elements distribution in cation positions ( x 1 and x 2) upon the ionic radii of Ln. Similar equations were derived for dependence of unit cell a, b, c parameters upon the “radius” of the (Ln,Ca)(1) and (Ca,Ln)(2) cation positions The equations enable the distribution of Y, Ca and dopants on cation sites to be proposed.

Circular asymmetry of the paleomagnetic directions observed at low latitude volcanic sites

The shape of the distribution in field directions and VGP positions was studied by Bingham statistics applied to a paleomagnetic dataset from lavas for the last 5 my by McElhinny and McFadden (1997), which includes those with VGP latitude higher than 45°. Data from Hawaii clearly show an oval shaped distribution of field directions, elongated along the meridian plane, while distribution of VGP is almost circular. Analysis on the global data divided by latitudinal bands also indicate more elongation in field directions for low latitude bands. This feature was interpreted as a general indication of dipole nature of the paleomagnetic field. For Hawaii data, however, possibility of the Pacific Nondipole Low is also suggested due to the large elongation parameter and very high significance of Fisher distribution to describe the VGP positions together with the small ASD. Although this elongated shape in the distribution of field directions is not clear for most of the individual site, the directions of the principal axes are sensitive enough to depict this feature at almost all sites.

FDTD analysis of field distribution in an elevatorcar byusing various antenna positions and orientations

In indoor coverage planning the lift car is considered to be one of the most difficult propagation environments. The authors have studied radiowave propagation in this environment by means of an FDTD simulation. The lift shaft and the transmitting antenna are also modelled. A short dipole antenna is placed at various orientations and positions and the influence of these factors on the electric field distribution in a lift car is examined. It is found that for practical lift car coverage planning purposes, the placement and orientation of a short dipole antenna are not of any significant importance.

Molecular evolution and host adaptation of Bordetella spp.: phylogenetic analysis using multilocus enzyme electrophoresis and typing with three insertion sequences.

A total of 188 Bordetella strains were characterized by the electrophoretic mobilities of 15 metabolic enzymes and the distribution and variation in positions and copy numbers of three insertion sequences (IS). The presence or absence of IS elements within certain lineages was congruent with estimates of overall genetic relationships as revealed by multilocus enzyme electrophoresis. Bordetella pertussis and ovine B. parapertussis each formed separate clusters, while human B. parapertussis was most closely related to IS1001-containing B. bronchiseptica isolates. The results of the analysis provide support for the hypothesis that the population structure of Bordetella is predominantly clonal, with relatively little effective horizontal gene flow. Only a few examples of putative recombinational exchange of an IS element were detected. Based on the results of this study, we tried to reconstruct the evolutionary history of different host-adapted lineages.

Species identification by the positional analysis of fatty acid composition in triacylglyceride of adipose and bone tissues

In a new attempt at species identification, the total composition and positional distribution of fatty acid in triacylglyceride (TG) of adipose and bone tissues were analyzed in human, bovine, pig, dog, cat and chicken tissues. Although the total fatty acid compositions of bovine and pig tissues were significantly different from those of human (different in more than half the fatty acids tested), dog, cat and chicken tissues showed a comparatively similar composition to human fatty acids composed of TG in both tissues. The TG in these tissues was also subjected to stereospecific analysis using pancreatic lipase, that is, the fatty acid distribution in positions 1,3 (not distinguished between 1 and 3) and 2 of the TG were determined. The distribution of fatty acids among the positions 1,3 and 2 in the TG of animal adipose and bone tissues was non-random. The distribution between position 2 and positions 1,3 seems to be governed by chain length and unsaturation in each animal. The shorter and more unsaturated fatty acids showed a greater tendency to occupy position 2 of TG. Although this rule appeared in all animals except the pig, the distribution of each fatty acid into position 2 was species-specific. The positional distribution of fatty acid in TG was identical among the same species and in different regions of the same body. Thus, even when species identification is difficult using the pattern of total fatty acid composition, the analysis of the positional distribution of fatty acid makes it possible to determine the species. From the present results, the evaluation of positional distribution of fatty acid in the TG is a useful tool for the identification of human tissues.

A finite element analysis of the effects of the abdomen on regional lung expansion

A finite element model of the dog lung, heart and abdomen, consisting of three solid linearly elastic bodies, was developed to study the effects of gravity on the vertical stress distribution and lung volume in different body positions at functional residual capacity (FRC). The geometry of the lung was obtained from an isolated dried dog lung after inflation to total lung capacity (TLC). The compliance of the rib cage, diaphragm and the abdomen was simulated by spring elements located on their surfaces. In the prone position, gravitational forces acting only on the lung contributed to the vertical gradient (0.19 cmH 2O/cm) in transpulmonary pressure (Ptp). This result was independent of chest wall compliance. In the supine position, the addition of the heart and abdomen with a compliant diaphragm and abdominal walls increased the vertical Ptp gradient to 0.53 cmH 2O/cm. In the head-up (upright) position, both heart and abdominal weight contributed to the vertical gradient (0.47 cmH 2O/cm). Diaphragmatic compliance was of less importance to the vertical gradient in the head-up and head-down positions in the absence of the abdomen. The smallest vertical gradient (0.11 cmH 2O/cm) was obtained in the head-down position with abdominal weight reducing the gradient caused by lung weight. Lung volume at FRC was virtually unaffected by gravity in the prone body position, was reduced by gravity in the supine and head-down positions but increased in the head-up position. The effects of a compliant diaphragm and abdominal weight are important contributors to the distribution of stress and volume in the intact lung.

1H-[13C] NMR measurements of [4-13C]glutamate turnover in human brain.

A limitation of previous methods for studying human brain glucose metabolism, such as positron emission tomography, is that metabolic steps beyond glucose uptake cannot be studied. Nuclear magnetic resonance (NMR) has the advantage of allowing the nondestructive measurement of 13C distribution in specific carbon positions of metabolites. In this study 1H-[13C] NMR spectroscopy in conjunction with volume localization was used to measure the rate of incorporation of 13C isotope from infused enriched [1-13C]glucose to human brain [4-13C]glutamate. In three studies C4 glutamate turnover time constants of 25, 20, and 17 min were measured in a 21-cm3 volume centered in the region of the visual cortex. Based on an analysis of spectrometer sensitivity the spatial resolution of the method can be improved to < 4 cm3. In conjunction with metabolic modeling and other NMR measurements this method can provide a measure of regional rates of the brain tricarboxylic acid cycle and other metabolic pathways.

Assessment of skin dose and its relation to cosmesis in conservative treatment of early breast cancer

A conservation technique has been developed for the treatment of early breast cancer which involved removal of the tumor, axillary clearance, tumor site implantation with Iridium-192 wires for a boost dose and subsequent treatment of the breast with radical megavoltage external beam therapy. Although the cosmetic results were satisfactory in the majority of the patients, for some it was rated as fair or poor. One variable factor which could have carried some morbidity was the dose of radiation received by the skin. In 51 patients, doses were measured at several points over the treated breast using Thermoluminescent Dosimetry (TLD) at the time of the iridium implant and during the subsequent external beam therapy. Development of skin pigmentation, oedema, and fibrosis were unrelated to the dose received by the skin but the findings suggested that doses greater than 50 Gy to the skin increased the possibility of late (>24 months) telangiectasia over the boosted area. Treatment of tumors in the lower half of the breast, or in large breasts, was associated with a higher incidence of poor cosmesis. This may have been the result of varying posture on the interstitial dose distribution from the Iridium-192 wires and comparison of dose distribution in both supine and erect positions was carried out.

Sonographic evidence of intraperitoneal fluid. An experimental study and its clinical implications.

In order to evaluate the sensitivity of ultrasound to intraperitoneal fluid, such as ascites or blood, an experimental study was performed in the pig. Various amounts of fluid were injected into the peritoneal cavity to investigate distribution and diagnostic criteria in different positions. As little as 10 ml of fluid was visualized around the urinary bladder in an upright position. In the supine position, 20 ml could be detected around the bladder and 30 ml around the liver. The injection of at least 60 ml resulted in a pattern of free-floating bowel loops. The sonographic findings of fluid distribution were correlated to radiological studies. As different amounts of fluid produce characteristic sonographic patterns, an approximate estimation of the intraperitoneal fluid volume can be made.

Superexchange interactions and magnetic microstructures of oxyfluoride ferrospinels

A Mossbauer study has been performed on a series of oxyfluoride ferrites based on nickel ferrite. Anion substitution results in new magnetically nonequivalent positions for the iron ions, which are characterized by lower local magnetic fields at the nucleus. The ratios between the different types of cations affect the cation distribution in the octahedral positions. The Neel temperatures calculated in this way describe the experimental values satisfactorily and indicate that the fluorine weakens the superexchange interaction between sublattices, which is confirmed also by the temperature dependence of the local magnetic fields at the iron ions with different anionic environments.

Positional distribution of fatty acids in triglycerides of animal depot fats

Several animal depot fats were subjected to stereospecific analysis, i.e., the fatty acid distribution in positions 1, 2, and 3 of the triglycerides were determined. The distribution of fatty acids among the positions 1, 2, and 3 in the triglycerides of animal depot fats is non-random. The distribution between position 2 and positions 1 and 3 seems to be governed by chain length and unsaturation. The shorter and the more unsaturated fatty acids show a greater tendency to occupy the position 2. This rule applies also to the apparent exceptions, the fats of pig and marine mammals, but in these the influence of chain length overrides that of unsaturation. On the other hand, in the three birds investigated unsaturation seems to be the only directing factor. We found fats with asymmetrical distribution of fatty acids as well as symmetrical fats. All mammalian fats were asymmetrical, as were the fats of one amphibian, one fish, and one arthropod, whereas the fats of one fish, one arthropod, and three birds were symmetrical. All asymmetrical fats have an excess of palmitic acid in position 1 and of oleic acid in position 3,

Effect of body posture on gas distribution in the lungs.

Postural changes of functional residual capacity (FRC) and pulmonary N2 clearance efficiency were studied in six male subjects placed supine on a tilting table, in head-up, horizontal and head-down positions. FRC varied linearly with the angle of tilt. The lung clearance index (LCI) increased significantly in the supine and head-down positions, compared to the head-up positions, which indicates less uniform gas distribution in the former postures. This was confirmed by analysis of semilogarithmic graphs of N2 washout. Inhalation of epinephrine did not affect the postural changes of FRC and LCI, but caused a small increase of LCI irrespective of posture. The increased uneven distribution in head-down and supine positions is probably a consequence of the lung volume decrease in these postures, and may be explained by mechanical factors such as surface tension, which tend to close lung units when the lungs are deflated. Bronchomotor tone has no appreciable influence on these postural changes in normal subjects. Submitted on July 13, 1961