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PubMedDate not supplied

Comparison of polarimetric retinal nerve fiber analyzer parameters for a single high quality image and the mean image from three high quality images.

BACKGROUND: To find the correlations and differences between the nerve fiber layer parameters of a GDx (polarimetric retinal nerve fiber analyzer) in single high quality images and those in the mean image from three high quality images. METHODS: The results of scanning laser polarimetry were selected from 63 eyes of 63 patients (31 male and 32 female). Complete ophthalmic examinations included slit-lamp biomicroscopy, dilated pupil for vitreous and ocular fundus examination, applanation tonometry, and subjective or objective refraction. There were no significant ophthalmic disorders other than glaucoma and mild lens opacity. Nerve fiber layer thickness of each eye was measured with GDx and at least three high quality images (passing the software's quality criteria) were obtained. The best of these three high quality images was selected as a single high quality image (Group One). The mean image (Group Two) was calculated from the same three high quality images. RESULTS: We found that there was a high correlation in all nerve fiber layer parameters between Group One and Group Two. There was no significant difference in the seven relative values of nerve fiber layer parameters (Number, Ellipse Modulation, Symmetry, Superior Ratio, Inferior Ratio, Superior/Nasal and Maximal Modulation) between Group One and Group Two. Group One had significantly higher values compared with Group Two in the other seven absolute values of nerve fiber layer parameters (Average Thickness, Ellipse Average, Superior Average, Inferior Average, Superior Integral, Superior Maximal and Inferior Maximal). CONCLUSION: It is reasonable to take a mean image from three good quality images from a cooperative patient. If only one high quality image can be obtained in repeated acquisition of GDx, the seven relative values of nerve fiber layer parameters in this high quality image can be used as a base-line image for detecting retinal nerve fiber layer defects and for determining changes of retinal nerve fiber layer thickness in sequential images of GDx.

Adolescent↗
PubMed1994

Diet quality index: capturing a multidimensional behavior.

OBJECTIVE: Data for 5,484 adults (aged 21 years and older) who participated in the 1987-88 Nationwide Food Consumption Survey (NFCS) were used to develop an index of overall dietary intake that related to the major, diet-related, chronic diseases in the United States. The low response rate of the 1987-88 NFCS has raised concerns about potential bias, but this large data set is useful for methodologic studies and research that does not attempt to generalize the results to the US population. ANALYSES: Dietary recommendations from the 1989 National Academy of Sciences publication Diet and Health were stratified into three levels of intake for scoring. Individuals who met a dietary goal were given a score of zero. Those who did not meet a goal, but had a fair diet, were given one point, and those who had a poor diet were given two points. These points were summed across eight diet variables to score the index from zero (excellent diet) to 16 (poor diet). RESULTS: Lower index scores were positively associated with high intakes of other important measures of diet quality (eg, fiber, vitamin C). We found that single nutrients (such as dietary fat) were not necessarily associated with other measures of diet quality. CONCLUSION: We concluded that this index ranking of overall dietary patterns was reflective of total diet quality, though substantial misclassification can result from using single nutrients or foods as indicators of diet quality.

Adult↗
PubMed2007

High-power 83 W holmium-doped silica fiber laser operating with high beam quality.

A high-power 83 W cladding-pumped Tm3+-Ho3+-doped silica fiber laser is reported. Using bidirectional 793 nm diode pumping, a maximum slope efficiency of 42% was produced after a threshold launched pump power of 12 W was exceeded. The laser operated at wavelengths near 2105 nm with moderate beam quality, i.e., M2 approximately 1.5. Further power scaling of the fiber laser was limited by thermal failure of the fiber ends.

Journal Article↗
PubMed2003

Quantity and quality of dietary fat, carbohydrate, and fiber intake in the German EPIC cohorts.

AIM: This evaluation aims to describe the quantity and quality of dietary fat, carbohydrate and fiber intake in both German cohorts participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). METHODS: Estimates are based on standardized computer-guided 24-hour dietary recalls from 1,078 women and 1,013 men in Heidelberg and 898 women and 1,032 men in Potsdam. In a subsample, plasma phospholipid (PL) fatty acids were analyzed as well. RESULTS: Adjusted mean dietary intake estimates demonstrated that the contribution of fat as well as n-6 and n-3 polyunsaturated fatty acids (PUFA) to the total daily energy intake was higher in both women and men of EPIC-Potsdam compared to EPIC-Heidelberg. Surprisingly, the dietary n-6/n-3 PUFA ratio was lower in the Potsdam cohort. These results were confirmed by means of the PL fatty acid pattern. Besides the higher contribution of polysaccharides to total energy intake in EPIC-Heidelberg, women of the Heidelberg cohort revealed a significantly lower contribution of mono- and disaccharides (sucrose) to total energy intake. Although total fiber intake data were similar in both cohorts, analysis by food groups showed differences in dietary fiber intake originating from the food groups cereals, fruits and potatoes. CONCLUSION: The results demonstrate distinct differences in the dietary fat, carbohydrate and fiber intake between both German EPIC cohorts, which contribute to the exposure variation in the whole of EPIC.

Adult↗
PubMed1991

Effects of dietary neutral detergent fiber concentration and alfalfa hay quality on chewing, rumen function, and milk production of dairy cows.

Six ruminally fistulated Holstein cows (80 d postpartum) were used in a 6 x 6 Latin square to evaluate the effects of dietary NDF concentration and alfalfa hay quality on chewing activities, digestive parameters, and productivity of dairy cattle. Cows received one of six diets formulated to provide three concentrations of dietary NDF (31, 34, and 37%) and two sources of first-cutting, long alfalfa hay. Alfalfa hay was harvested either in early bloom (19.4% CP, 38.8% NDF) or midbloom (16.7% CP, 47.6% NDF) stages of maturity. Dietary NDF concentrations were achieved by adjusting the forage to concentrate ratios. Mean ad libitum DMI was 22.3 kg/d. Increased NDF concentration of the diet corresponded to a linear decrease in milk production (from 26.5 to 24.8 kg/d) and a linear increase in the fat content of milk (from 2.68 to 3.30%). Hay quality had no effect on milk production and composition when diets were formulated for specific NDF concentrations. Total chewing time increased from 767 to 796 and 853 min/d as fiber content of the diet increased from 31 to 34 and 37%, mainly because of increased time spent eating. Rumination time adjusted for fiber intake decreased linearly from 59.0 to 54.2 min/kg NDF as fiber intake increased, and it was higher for the early bloom than for the midbloom hay (57.3 vs. 55.5 min/kg NDF). Effects of decreased forage quality because of the increased maturity of the alfalfa hay can be minimized by formulating diets for specific NDF concentration. For diets formulated with barley-based concentrates, dietary NDF concentrations should be higher than currently recommended with allowance for greater proportions of NDF from concentrates.

Ammonia↗
PubMed1995

Effects of growth hormone and ovariectomy on performance, serum hormones, insulin-like growth factor-binding proteins, and muscle fiber properties of prepubertal Friesian heifers.

Sixteen prepubertal Friesian heifers were used to examine the effect of bovine growth hormone (GH) and ovariectomy (OVX) at 2.5 mo of age (2 x 2 factorial design) on growth, carcass quality, and fiber types, capillarization, and metabolic potentials of the longissimus muscle, and serum concentrations of estradiol-17beta (E2beta), insulin, GH, IGF-I, and IGF-binding proteins (IGFBP). Treatment with GH (15 mg/d) started at 147 +/- 3 kg BW and lasted for 15 wk. Heifers were fed a mixed roughage-based diet. Growth hormone increased ADG (P < .001), improved gain:feed (P < .007), and had a small but positive influence on lean accretion. Growth hormone reduced fat thickness (P < .009), carcass fat trim (P < .009) and i.m. fat (P < .09). Ovariectomy did not affect performance but increased dressing percentage (P < .03), full rib weight (P < .003), and fat thickness (P < .04). Ovariectomy reduced E2beta (P < .001) and insulin (P < .02), and increased the 32-kDa IGFBP (IGFBP-2) (P < .09). Growth hormone treatment increased GH, IGF-I, the 28-kDa IGFBP, and the 40- to 43-kDa IGFBP (IGFBP-3) (P < .004 or P < .001). Neither GH nor ovariectomy affected the proportion and relative area of the individual muscle fiber types, but GH tended to increase type I fiber area (P < .10). Number of capillaries per fiber increased in OVX GH-treated heifers (GH x OVX interaction, P < .02). Activities of citrate synthetase were higher in GH-treated (P < .05) and OVX (P < .02) heifers, indicating increased oxidative capacity of the longissimus muscle. The effects of GH on performance and carcass fattening were in accordance with the observed hormonal changes. When slaughter occurs before puberty, ovariectomy has no effect on performance, only few effects on carcass quality, and small effects on hormone concentrations.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed2006

Partial least squares regression calibration for determining wax content in processed flax fiber by near-infrared spectroscopy.

The quality of flax fiber in the textile industry is closely related to the wax content remaining on the fiber after the cleaning process. Extraction by organic solvents, which is currently used for determining wax content, is very time consuming and produces chemical waste. In this study, near-infrared (NIR) spectroscopy was used as a rapid analytical technique to develop models for wax content associated with flax fiber. Calibration samples (n=11) were prepared by manually mixing dewaxed fiber and isolated wax to provide a range of wax content from 0 to 5%. A total of fourteen flax fiber samples obtained after a cleaning process were used for prediction. Principal component analysis demonstrated that one principal component is enough to separate the flax fibers by their wax content. The most highly correlated wavelengths were 2312, 2352, 1732, and 1766 nm, in order of significance. Partial least squares models were developed with various chemometric preprocessing approaches to obtain the best model performance. Two models, one using the entire region (1100-2498 nm) and the other using the selected wavelengths, were developed and the accuracies compared. For the model using the entire region, the correlation coefficient (R2) between actual and predicted values was 0.996 and the standard error of prediction (RMSEP) was 0.289%. For the selected-wavelengths model, the R2 was 0.997 and RMSEP was 0.272%. The results suggested that NIR spectroscopy can be used to determine wax content in very clean flax fiber and that development of a low-cost device, using few wavelengths, should be possible.

Calibration↗
PubMed2000

[Studies on relationship between exposure to low concentration of mixed benzene and lower quality of semen and very early fetal loss].

OBJECTIVE: To study the effects of exposure to low concentration of mixed benzene on their semen quality and very early fetal loss (VEFL) in the occupational population. METHODS: Environmental monitoring and biological monitoring were conducted in 126 employees exposed to mixed benzene and 60 unexposed ones selected from a large petrochemical corporation and a large chemical fiber corporation. Quality of semen in 70 male workers in the exposed group and 90 male internal controls and 132 male external controls were analyzed, and urinary beta-human chorionic gonadotropin (beta-hCG) was determined for 42 female exposed workers and 49 female internal controls and 118 external controls. RESULTS: 1. Exposure to mixed benzene mainly existed in low concentrations (0.7-27.0 mg/m3) in the petrochemical corporation, and urine concentration of t, t-MA in the workers correlated significantly to benzene concentration in ambient air of the workshops (r = 0.64, P = 0.03). 2. The sperm progression and motility in the exposed (1.97 +/- 0.63 and 0.55 +/- 0.16) and the internal control (1.97 +/- 0.69 and 0.55 +/- 0.17) groups were significantly (P < 0.05) lower than those in the external control group (2.56 +/- 0.61 and 0.60 +/- 0.13), however, the sperm abnormality rates in the exposed and internal control groups were significantly (P < 0.01) higher than those in the external control group, and the summary abnormality rate of sperm in the exposed group (85.71%) was higher than that in the internal (70.00%) and external control (76.51%) groups (P < 0.05). 3. The incidence rates of the VEFL in female workers and the cyclic occurrence of VEFL both in the exposed and internal control groups (10.42% and 9.60%) were higher than those in the external control group (5.09%), with statistical significance (P < 0.05). CONCLUSIONS: Exposure to low concentration of mixed benzene maybe correlated with the declined quality of semen and VEFL in occupational workers, and urinary t, t-MA and beta-hCG can be used as biomarkers of exposure and effect, respectively.

Abortion, Spontaneous↗
PubMed2003

Temporal characterization of short pulses stretched by fiber Bragg gratings.

Short femtosecond pulses at 1054 nm are stretched up to 400 ps by long broadband chirped-fiber Bragg gratings. The temporal profile of the reflected pulses is measured with a cross-correlation scheme. The advantage of this technique over the usual spectral measurements is its high sensitivity, since the temporal profile of reflected pulses is revealed to be strongly affected by the presence of defects in the grating. We show that this method is a good test of the quality of fiber Bragg gratings.

Journal Article↗
PubMed2006

Potato glycoalkaloids and metabolites: roles in the plant and in the diet.

Potatoes, members of the Solanaceae plant family, serve as major, inexpensive low-fat food sources providing energy (starch), high-quality protein, fiber, and vitamins. Potatoes also produce biologically active secondary metabolites, which may have both adverse and beneficial effects in the diet. These include glycoalkaloids, calystegine alkaloids, protease inhibitors, lectins, phenolic compounds, and chlorophyll. Because glycoalkaloids are reported to be involved in host-plant resistance and to have a variety of adverse as well as beneficial effects in cells, animals, and humans, a need exists to develop a clearer understanding of their roles both in the plant and in the diet. To contribute to this effort, this integrated review presents data on the (a) history of glycoalkaloids; (b) glycoalkaloid content in different parts of the potato plant, in processed potato products, and in wild, transgenic, and organic potatoes; (c) biosynthesis, inheritance, plant molecular biology, and glycoalkaloid-plant phytopathogen relationships; (d) dietary significance with special focus on the chemistry, analysis, and nutritional quality of low-glycoalkaloid potato protein; (e) pharmacology and toxicology of the potato glycoalkaloids comprising alpha-chaconine and alpha-solanine and their hydrolysis products (metabolites); (f) anticarcinogenic and other beneficial effects; and (g) possible dietary consequences of concurrent consumption of glycoalkaloids and other biologically active compounds present in fresh and processed potatoes. An enhanced understanding of the multiple and overlapping aspects of glycoalkaloids in the plant and in the diet will benefit producers and consumers of potatoes.

Animals↗
PubMed1995

Advantages and limits of in vivo screening tests.

Several methods have been proposed to ascertain the potential toxicity of man-made vitreous fibres (MMVF) in animals. The most frequently used in vivo methods include inhalation (IH) (whole body and nose-only), intratracheal (IT) instillation, intrapleural injection-implantation and intraperitoneal (IP) injection. This report compares reports of studies using these methods in terms of their: (1) relevance to humans; (2) standardization of technique; (3) validation of method; (4) need for fibre preparation; (5) estimation of maximum tolerated dose; (6) determination of 'overload'; (7) exposure regimen; (8) pathology requirements; (9) quality control procedures; (10) extent and type of peer review; and (11) value of data for risk assessment. The results of this investigation showed that the inhalation method was clearly superior to the other exposure methods in all respects, although it is the most expensive. The intratracheal instillation method was considered a second choice, while injection-implantation methods were fraught with scientific and practical problems and the data derived from studies using these techniques were considered of value only for the study of specific mechanistic issues.

Animals↗
PubMed2004

Analysis of biologically active compounds in potatoes (Solanum tuberosum), tomatoes (Lycopersicon esculentum), and jimson weed (Datura stramonium) seeds.

Potatoes and tomatoes, members of the Solanaceae plant family, serve as major, inexpensive low-fat food sources providing for energy, high-quality protein, fiber, vitamins, pigments, as well as other nutrients. These crops also produce biologically active secondary metabolites, which may have both adverse and beneficial effects in the diet. This limited overview, based largely on our studies with the aid of HPLC, TLC, ELISA, GC-MS, and UV spectroscopy, covers analytical aspects of two major potato trisaccharide glycoalkaloids, alpha-chaconine and alpha-solanine, and their hydrolysis products (metabolites) with two, one, and zero carbohydrate groups; the potato water-soluble nortropane alkaloids calystegine A3 and B2; the principal potato polyphenolic compound chlorogenic acid; potato inhibitors of digestive enzymes; the tomato tetrasaccharide glycoalkaloids dehydrotomatine and alpha-tomatine and hydrolysis products; the tomato pigments beta-carotene, lycopene, and chlorophyll; and the anticholinergic alkaloids atropine and scopolamine present in Datura stramonium (jimson weed) seeds that contaminate grain and animal feed. Related studies by other investigators are also mentioned. Accurate analytical methods for these food ingredients help assure the consumer of eating a good-quality and safe diet.

Chromatography, High Pressure Liquid↗
PubMed2004

Biological natural retting for determining the hierarchical structuration of banana fibers.

Extraction processes of natural fibers can be performed by different procedures that include mechanical, chemical and biological methods. Each method presents different advantages or drawbacks according to the amount of fiber produced or the quality and properties of fiber bundles obtained. In this study, biological natural retting was satisfactorily used for obtaining banana fibers from plant bunches. However, the most important contribution of this work refers to the description of the hierarchical microstructural ordering present in banana fiber bundles in both bundle surface and inner region. The chemical composition of banana fiber bundles has been evaluated by FTIR spectroscopy. Through exposure time, the fiber bundle configuration presents small variations in composition. The main changes are related to hemicellulose and pectins as they conform the outer walls of the bundle. Hierarchical helicoidal ordering in the bundle surface as well as orientation on the longitudinal axis of the bundle were observed by optical microscopy (OM) and scanning electron microscopy (SEM) for 3-4 microm surface fibers and 10-15 microm inner elementary fibers, respectively. With increasing exposure time, fiber bundle walls lose integrity, as reflected in their mechanical behavior.

Biological Products↗
PubMed2005

Chemical characterization of pitch deposits produced in the manufacturing of high-quality paper pulps from hemp fibers.

The composition of pitch deposits occurring in pulp sheets and mill circuits during soda/anthraquinone pulping and elemental chlorine-free pulp bleaching of bast fibers of industrial hemp (Cannabis sativa) was studied. Pitch deposits were extracted with acetone, and the extracts analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). Acetone extracts (15-25% of pitch deposits) were constituted by the defoamers used at the mill and by lipophilic extractives from hemp fibers. Acetone-insoluble residues (75-85% of pitch deposits) were analyzed by pyrolysis-GC/MS in the presence and absence of tetramethylammonium hydroxide. These residues were constituted by salts of fatty acids (arising from hemp fibers) with calcium, magnesium, aluminum and other cations that were identified in the deposits. It was concluded that inappropriate use of defoamer together with the presence of multivalent ions seemed to be among the causes of hemp extractives deposition in the pitch problems reported here.

Acetone↗
PubMed1998

Interventional nutrition for the cancer patient.

Dogs and cats with cancer have significant alterations in carbohydrate, protein, and fat metabolism, which can result in cancer cachexia and subsequently can decrease quality of life, reduce response to therapy, and shorten survival time. Nutritional modulation may be beneficial in the treatment of cancer patients to reverse these metabolic alterations. There is evidence that foods relatively low in simple carbohydrates with moderate amounts of high-quality protein, fiber, and fat (especially fats of the omega-3 fatty acid series) are beneficial for pets with cancer. In addition, certain supplemental nutrients may have potential to reduce the risk of developing cancer, or the growth and metastases of established malignant disease. Nutritional intervention can be a powerful tool for controlling malignant disease and for reducing toxicity associated with chemotherapy and radiation therapy.

Animals↗
PubMed2003

Seasonal, spatial, and interspecific variation in quercetin in Apocynum venetum and Poacynum hendersonii, Chinese traditional herbal teas.

Quercetin is of particular importance as it has been found to have functions of suppressing tumors, reducing blood pressure, and scavenging free radicals. It is one of the major flavonoids in Apocynum venetum and Poacynum hendersonii, whose leaves have long been used as traditional herbal teas in China and Japan. Both species are also cultivated as fiber plants because of their outstanding quality of phloem fiber in stems. To obtain high output of both quercetin and fiber, it is necessary to optimize harvesting time for their leaves. Thus, understanding the developmental patterns of quercetin in leaves and fiber in stems is crucial to achieving this goal. In the present study, temporal and interspecific variations in quercetin in the leaves between A. venetum and P. hendersonii and spatial variation among P. hendersonii populations were studied by HPLC during the period from April to October in 1999. The results show that the content of quercetin in both species reached its highest level in summer and its lowest in autumn. The quercetin content in the leaves of P. hendersonii was generally higher than that of A. venetum no matter when their leaves were harvested. There was significant difference in quercetin content among three geographical populations of P. hendersonii, which might be the result of climatic difference-cooler climate might favor accumulation of quercetin in the leaves of P. hendersonii. Furthermore, the developmental patterns of total phenolics in the leaves of the two species were the same as that of the quercetin, that is, summer is an optimal harvesting season for both quercetin and other phenolics. The results obtained here suggest that P. herdersonii is a better material for herbal tea or pharmaceutical purposes, and that the best harvest time of its leaves should be summer.

Apocynum↗
PubMed2001

A proposal for harmonising laboratory performance assessment criteria in national asbestos fibre counting schemes.

Four European national asbestos fibre counting proficiency testing schemes have been studied in order to compare their criteria for the assessment of laboratory performance. Performance assessment is based on each laboratory's results after counting a certain number of samples. Two methods are currently being applied. To be classified 'satisfactory' laboratories must obtain at least 75% of normalised counts lying within defined performance limits (in three schemes), or the median and coefficient of variation of normalised counts must be within performance limits (in the fourth scheme). Differences in the numbers of test samples mean that the schemes are operating with different selectivity in assessing their laboratories' performances. Differences in the percentage of laboratory results falling within performance limits indicate that the schemes do not operate the same confidence probability in correctly assessing individual counts. It means that some schemes may be more lenient than others. This paper discusses two proposals to move towards harmonisation of the asbestos fibre counting proficiency testing schemes: (i) standardisation of the number of samples used for laboratory assessment and (ii) changes to the criteria to establish the limits of satisfactory performance.

Asbestos↗
PubMed2003

A deformable finite element derived finite difference method for cardiac activation problems.

We present a finite element (FE) derived finite difference (FD) technique for solving cardiac activation problems over deforming geometries using a bidomain framework. The geometry of the solution domain is defined by a FE mesh and over these FEs a high resolution FD mesh is generated. The difference points are located at regular intervals in the normalized material space within each of the FEs. The bidomain equations are then transformed to the embedded FD mesh which provides a solution space that is both regular and orthogonal. The solution points move in physical space with any deformation of the solution domain, but the equations are set up in such a way that the solution is invariant as it is constructed in material space. The derivation of this new solution technique is presented along with a series of examples that demonstrate the accuracy of this bidomain framework.

Action Potentials↗