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Quantitative Imaging Ion Microscopy: A Short Review, G. A. Valaskovic, G. H. Morrison Mar 1992

Quantitative Imaging Ion Microscopy: A Short Review, G. A. Valaskovic, G. H. Morrison

Scanning Microscopy

A short review of recent efforts being made in the quantification of images in ion microscopy is given. Special aspects of instrumentation, detection and acquisition, which are unique to direct imaging secondary ion mass spectrometry, are discussed in relation to the successful application of traditional empirical quantification schemes. Application of such quantification schemes requires proper sample preparation, standardization, analysis, and quite often, special techniques in image processing and the correlation of ion microscopy with other microscopies. Quantification within this technique is a difficult goal which can only be realized if the analyst pays strict attention to every step of the …


The Mayfly Newsletter, Peter M. Grant Mar 1992

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Development Of Mass-Rearing Techniques For Aphelinus Asychis Walker For Use In A Biological Control Program Against Russian Wheat Aphid, Robin Lynn Whitaker-Deerberg Mar 1992

Development Of Mass-Rearing Techniques For Aphelinus Asychis Walker For Use In A Biological Control Program Against Russian Wheat Aphid, Robin Lynn Whitaker-Deerberg

Theses and Dissertations - UTB/UTPA

Mass-rearing techniques were developed for the parasitoid Aphelinus asychis Walker (Hymenoptera:Aphelinidae) for use in a biological control program against the Russian wheat aphid, Diuraphis noxia (Mordvilko) (Homoptera:Aphididae). Daily ovipositional activity, host-feeding behavior, effects of population density in the rearing cages and effects of cold storage on mummies were determined.

Daily ovipositional activity peaked at day 5 after emergence of the parasitoid. Ninety-two percent of mummies resulting from ovipositional activity were oviposited the first 13 days of the parasitoid’s life. Since mummification occurred 11 days after oviposition and emergence occurred 11 days after mummification, day 24 was determined to be the …


Lek Formation In Sage Grouse: The Effect Of Female Choice On Male Territory Settlement, Robert M. Gibson Mar 1992

Lek Formation In Sage Grouse: The Effect Of Female Choice On Male Territory Settlement, Robert M. Gibson

School of Biological Sciences: Faculty Publications

Previous studies of female choice in sage grouse, Centrocercus urophasianus, have identified two processes that could drive the local clustering of male territories at leks: (1) fidelity of females to previous mating sites (“temporal spillover” hypothesis), and (2) “spatial spillover” of matings from an attractive male to his immediate neighbors (“hotshot” hypothesis). The effects of each process on male territory settlement were investigated using observations of the resettlement of vacant territories and of individual site fidelity during a 7-year field study. The frequency with which vacant territories were resettled both within and between seasons increased with mating success of …


Correlative Transmission Electron Microscopy And High Resolution Scanning Electron Microscopy Studies On The Fine Structural Organization Of The Chicken Pituitary Gland, Susan Tai Feb 1992

Correlative Transmission Electron Microscopy And High Resolution Scanning Electron Microscopy Studies On The Fine Structural Organization Of The Chicken Pituitary Gland, Susan Tai

Scanning Microscopy

The present study employs transmission (TEM) and high-resolution scanning electron microscopy (HR-SEM) to examine the inter- and intra-cellular organization of the pars distalis of the chicken anterior pituitary gland. The overall view of the cryofractured surface of the par distalis illustrates the arrangement of different pituitary cells and tissues in the follicles. Fine structural examination by HR-SEM shows that the membrane of the mitochondria has a similar configuration to that of the rough endoplasmic reticulum. Granule-like structures, on the surface of the mitochondrial membrane, are similar in size to ribosomes. Standard imaging and three-dimensional imaging demonstrated the formation of developing …


The Ionic Composition Of Ion Transporting Cells In Stonefly Nymphs, W. T. W. Potts, I. Bricknell Feb 1992

The Ionic Composition Of Ion Transporting Cells In Stonefly Nymphs, W. T. W. Potts, I. Bricknell

Scanning Microscopy

Freshwater stonefly larvae take up sodium and chloride ions from low concentrations in water and concentrate them into haemolymph. The ions are transported by mitochondria rich cells (MRITCs) which are easily identified by their windows in the cuticle. Sodium uptake is generally inhibited at low pH but a few species of stoneflies live in acid waters. Acid tolerance is associated with presence of caviform or bulbiform MRITCs while nymphs possessing only the more common coniform cells are sensitive to acid conditions.

The intracellular concentrations of Na, K, Cl and P in coniform cells of Perla bipunctata and bulbiform cells of …


A Light, Transmission And Scanning Electron Microscope Study Of Snuff-Treated Hamster Cheek Pouch Epithelium, S. H. Ashrafi, A. Das, R. Worowongvasu, B. Mehdinejad, J. P. Waterhouse Feb 1992

A Light, Transmission And Scanning Electron Microscope Study Of Snuff-Treated Hamster Cheek Pouch Epithelium, S. H. Ashrafi, A. Das, R. Worowongvasu, B. Mehdinejad, J. P. Waterhouse

Scanning Microscopy

The effects of smokeless tobacco (snuff) on hamster cheek mucosa were studied by light microscopy, transmission (TEM) and scanning electron microscopy (SEM). Two grams of commercially available smokeless tobacco were placed into the blind end of the right cheek pouch of each experimental animal, once a day and five days a week for 24 months. The control animals did not receive smokeless tobacco. After 24 months treatment with smokeless tobacco, hamster cheek mucosal epithelium lost its translucency and had become whitish in color. By light microscopy hyperorthokeratosis, prominent granular cell layers with increased keratohyalin granules and hyperplasia were seen. At …


Nitrogen And Carbon Isotope Studies Of A Bat Guano Core From Eagle Creek Cave, Arizona, Usa, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya Feb 1992

Nitrogen And Carbon Isotope Studies Of A Bat Guano Core From Eagle Creek Cave, Arizona, Usa, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya

WM Keck Science Faculty Papers

Nitrogen and carbon isotope ratios were studied in a stratified deposit of guano of Mexican Free-tailed bats in Eagle Creek Cave, Arizona, U.S.A. Little diagenetic change was observed over the 25-year time span of the guano deposit. High aridity and reduced circulation of air in the cave are hypothesized to have slowed the normally rapid decomposition of the excreta and the subsequent escape of resultant ammonia. The results suggest the high dependency of the speed of diagenetic change on specific physical and other conditions of the caves and indicate that great care need be exercised in the interpretation of the …


Carbon And Nitrogen Isotopic Signatures Of Bat Guanos As A Record Of Past Environments, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya Feb 1992

Carbon And Nitrogen Isotopic Signatures Of Bat Guanos As A Record Of Past Environments, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya

WM Keck Science Faculty Papers

Carbon and nitrogen isotope ratios were measured for various ecogeochemical samples relevant to bat guano ecosystems. In particular, ca. 800-year-old subfossil guano from Jackson's Bay Cave Compex, Jamaica, yielded ratios similar to the modern guano from other Jamaican bat caves but quite different from modern guano of the same area. Diagenetic change and differences in bat food habits were unlikely explanations for the observation. Instead, insects that feed on C4 and CAM plants were the main prey for the bats in present Jackson's Bay area, while the ultimate source of organic matter for bats in other Jamaican caves and for …


Model Of Dietary Fiber Utilization By Small Mammalian Herbivores, With Empirical Results For Neotoma, Felisa A. Smith, Keith E. Justice Feb 1992

Model Of Dietary Fiber Utilization By Small Mammalian Herbivores, With Empirical Results For Neotoma, Felisa A. Smith, Keith E. Justice

Biology Faculty & Staff Publications

Allometric considerations have suggested that small herbivores are inefficient at or incapable of extracting energy from the microbial fermentation of structural carbohydrates. This notion is at odds with accumulating empirical evidence that demonstrates well-developed fiber digestion abilities for a number of small rodent genera. To examine the apparent inconsistency, we have constructed a model of plant fiber utilization tailored specifically for hindgut fermenters. Computer simulations provide estimates of fiber and overall dry-matter digestibilities as a function of body size, energy demand, and diet. Our calculations indicate that small mammals can obtain significant benefit from fiber fermentation, especially at moderate fiber …


Structural Artifacts And Advantages Of Cytocentrifugation Of Cells As Viewed By Scanning Electron Microscopy, Mário N. D. Peão, Artur P. Águas, Carlos Moreira De Sá, Nuno R. Grande Jan 1992

Structural Artifacts And Advantages Of Cytocentrifugation Of Cells As Viewed By Scanning Electron Microscopy, Mário N. D. Peão, Artur P. Águas, Carlos Moreira De Sá, Nuno R. Grande

Scanning Microscopy

Cytocentrifugation of cell suspensions onto glass slides is a widely used procedure in contemporary cytology. We employed here scanning electron microscopy (SEM) to investigate putative morphological changes induced in cells submitted to cytocentrifugation. The fine structure of murine pleural exudate cells (macrophages mainly) processed by spinning was compared with that of similar cells treated without centrifugation (poly-L-lysine attachment of the cells to glass slides at 1 g). Cells of cytocentrifuged preparations showed a significant increase in diameter and smoothening of the cell surface as compared with the morphology of non-centrifuged cells. Cytocentrifugation also induced the formation of thin elongations coming …


Idiopathic Calcium Oxalate Nephrolithiasis: A Cellular Disease, Giovanni Gambaro, Bruno Baggio Jan 1992

Idiopathic Calcium Oxalate Nephrolithiasis: A Cellular Disease, Giovanni Gambaro, Bruno Baggio

Scanning Microscopy

Physico-chemical, metabolic and hormonal theories regarding the pathogenesis of calcium oxalate nephrolithiasis do not sufficiently explain many features of this disease. The recent findings of an abnormally faster oxalate self-exchange and higher phosphorylation of band 3 in erythrocytes of idiopathic calcium oxalate stone formers suggest the hypothesis that nephrolithiasis may be a cellular disease, characterized by a defect in the function of the anion-exchange. The cellular anomaly seems genetically controlled. Band 3 anion exchanger function seems to be biochemically regulated through modulation of band 3 phosphorylation, which depends on cyclic AMP- and phospholipid-sensitive Ca2+ independent protein kinases. In this …


Partial Characterization Of The Major Lipooligosaccharide From A Strain Of Haemophilus Ducreyi, The Causative Agent Of Chancroid, A Genital Ulcer Disease, William Melaugh, Nancy J. Phillips, A A. Campagnari, R Karalus, B W. Gibson Jan 1992

Partial Characterization Of The Major Lipooligosaccharide From A Strain Of Haemophilus Ducreyi, The Causative Agent Of Chancroid, A Genital Ulcer Disease, William Melaugh, Nancy J. Phillips, A A. Campagnari, R Karalus, B W. Gibson

Chemistry Faculty Publications

The first preliminary structure of a surface lipooligosaccharide from Haemophilus ducreyi has been determined. The major oligosaccharide was released by mild acid hydrolysis and analyzed by liquid secondary ion and tandem mass spectrometry. The mass spectral data combined with composition and methylation analysis yielded the most probable structure; Gal1----4GlcNAc1----3Gal1----4Hep1----6Glc1----( Hep1----2Hep1----)3,4Hep1---- KDO, where the reducing terminal 3-deoxy-D-manno-octulosonic acid (or KDO) exists in an anhydro form. This anhydro species results from the elimination of a phosphate from C-4 of KDO during mild acid hydrolysis. The core heptose trisaccharide consists of L-glycero-D-manno-heptose, but analysis of the peracetylated sugars indicated that the 1,4-linked heptose …


Effects Of Moose Foraging On Browse Availability In New Hampshire Deer Yards, Michael T. Pruss, Peter J. Pekins Jan 1992

Effects Of Moose Foraging On Browse Availability In New Hampshire Deer Yards, Michael T. Pruss, Peter J. Pekins

New Hampshire Agricultural Experiment Station Publications

Food habits of moose (Alces alces) and white-tailed deer (Odocoileus virginianus) overlap in northern New Hampshire during autumn and winter. High moose and deer densities in deer yards, where deer may be confined for extended periods, could result in competition for limited deciduous forage. The purpose of this study was to investigate possible impacts by moose on browse availability in deer yards, and the potential effects on deer. Fifteen deer yards were studied in northern New Hampshire during spring and fall, 1990-91. Unbrowsed and browsed deciduous twigs, and deer and moose pellet groups were counted on 900 permanent plots to …


An Examination And Correction Of Plant Tissue Culture Basal Medium Formulations, Henry R. Owen, A. Raymond Miller Jan 1992

An Examination And Correction Of Plant Tissue Culture Basal Medium Formulations, Henry R. Owen, A. Raymond Miller

Faculty Research & Creative Activity

The inorganic formulations of fourteen common plant tissue culture basal media were examined from the primary literature. Inaccuracies and errors were found for molecular formulae, chemical hydrations, and molar equivalences for iron/EDTA complexation. A comparison with published basal medium formulations from six commercial suppliers uncovered additional inaccuracies, modifications, and errors, thereby emphasizing the need for investigators to examine and describe medium formulations precisely in future publications.


Confocal Microscopy And Three-Dimensional Reconstruction Of Thick, Transparent, Vital Tissue, Barry R. Masters Jan 1992

Confocal Microscopy And Three-Dimensional Reconstruction Of Thick, Transparent, Vital Tissue, Barry R. Masters

Scanning Microscopy

The three-dimensional visualization of the 400 micron thick, transparent, in situ cornea is described to demonstrate the use of confocal light microscopy for noninvasive imaging of living cells and thick tissues in their normal, vital conditions. Specimen preparation and physiological stability, as well as light attenuation corrections are critical to data acquisition. The technique to provide mechanical stability of the specimen during the duration of the image acquisition is explained. A laser scanning confocal light microscope (LSCM) was used to obtain optical serial sections from rabbit eyes that were freshly removed and placed in a physiological Ringer's solution. This study …


Aspects Of Air Pollution, And Its Effect On The Respiratory System, Jennifer Randall Jan 1992

Aspects Of Air Pollution, And Its Effect On The Respiratory System, Jennifer Randall

Presidential Scholars Theses (1990 – 2006)

This report centers around one of today's most prominent environmental issues-- air pollution. First, the major pollutants are defined and explained. Chloroflourocarbons, ozone, carbon monoxide, carbon dioxide, methane, sulfur dioxide, nitrogen oxides, and suspended particulate matter all receive attention.

Next, air pollution's effect on the Earth is explained. The "greenhouse effect", global warming, acid rain, and ozone depletion all have an enormous impact on Earth's climate and atmosphere.

The report proceeds on to discuss options for controlling and so lving the air pollution problem. Se+ective catalytic reduction, noncatalytic reduction, tradeable permits-- these three processes are examples of large scale attempts …


Localization Of A Collagenous Protein In The Organic Matrix Of Spicules From The Octocoral Leptogorgia Virgulata (Cnidaria: Gorgonacea), Jeffrey L. Dupree Jan 1992

Localization Of A Collagenous Protein In The Organic Matrix Of Spicules From The Octocoral Leptogorgia Virgulata (Cnidaria: Gorgonacea), Jeffrey L. Dupree

Master's Theses

Calcareous body inclusions are commonly found throughout the invertebrate taxa. Elaborately structured calcium carbonate spicules are the major mineralized body inclusions of the gorgonian, Leptogorgia virgulata. Spicule formation in this octocoral, as well as other calcium carbonate invertebrate structures, is apparently regulated by the intra-spicule organic matrix. Recent findings show that the insoluble fraction of the spicule organic matrix is collagenous. Collagen, although integral to calcium phosphate structures found in vertebrates is not usually associated with the formation of invertebrate calcium carbonate structures. Interestingly, collagen is present in the organic matrix during the summer but absent in winter. This suggests …


Further Analysis Of Allozyme Variation In The Northern Flicker, In Comparison With Mitochondrial Dna Variation, Stephen D. Fletcher, William S. Moore Jan 1992

Further Analysis Of Allozyme Variation In The Northern Flicker, In Comparison With Mitochondrial Dna Variation, Stephen D. Fletcher, William S. Moore

Biological Sciences Faculty Research Publications

No abstract provided.


Molecular Basis Of Loss-Of-Function Mutations In The Glp-1 Gene Of Caenorhabitis Elegans, Voula Kodoyianni, Eleanor M. Maine, Judith Kimble Jan 1992

Molecular Basis Of Loss-Of-Function Mutations In The Glp-1 Gene Of Caenorhabitis Elegans, Voula Kodoyianni, Eleanor M. Maine, Judith Kimble

Biology - All Scholarship

The glp-1 gene encodes a membrane protein required for inductive cell interactions during development of the nematode Caenorhabditis elegans. Here we report the molecular characterization of 15 loss-of-function (lf) mutations of glp-1. Two nonsense mutations appear to eliminate glp-1 activity; both truncate the glp-1 protein in its extracellular domain and have a strong loss-of-function phenotype. Twelve missense mutations and one in-frame deletion map to sites within the repeated motifs of the glp-1 protein (10 epidermal growth factor [EFG]-like and 3 LNG repeats extracellularly and 6 cdc10/SW16, or ankyrin, repeats intracellularly). We find that all three types of repeated motifs are …


Effect Of Temperature And Humidity On Evaporative Water Loss In Anna's Hummingbird (Calypte Anna), Donald R. Powers Jan 1992

Effect Of Temperature And Humidity On Evaporative Water Loss In Anna's Hummingbird (Calypte Anna), Donald R. Powers

Faculty Publications - Department of Biological & Molecular Science

Evaporative water loss (EWL), oxygen concumption (V0 ), and body temperature (Tb) of Anna's 2 Hummingbirds (Calypte anna; ca. 4.5 g) were measured at combinations of ambient temperature (T J and water vapor density (Qva) ranging from 20 to 37 °C and 2 to 27 g · m-3 , respectively. The EWL decreased linearly with increasing eva at all temperatures. The slopes ofleast squares regression lines relating EWL to Qva at different temperatures were not significantly different and averaged -0.50mg H20·m-3 ·g-2 ·h-1 (range: -0.39 to -0.61). Increased Qva restricted EWL in C. anna more than has been reported for …


Detection Of Dimethylallypyrophosphate : 5'Amp Transferase Enzyme In Saccharomyces Cerevisiae, Raymond J. Federico Jan 1992

Detection Of Dimethylallypyrophosphate : 5'Amp Transferase Enzyme In Saccharomyces Cerevisiae, Raymond J. Federico

Master's Theses

No abstract provided.


Modulation By Camp Of A Slowly Activating Potassium Channel Expressed In Xenopus Oocytes, Edward M. Blumenthal, Leonard K. Kaczmarek Jan 1992

Modulation By Camp Of A Slowly Activating Potassium Channel Expressed In Xenopus Oocytes, Edward M. Blumenthal, Leonard K. Kaczmarek

Biological Sciences Faculty Research and Publications

When expressed in the Xenopus oocyte, the minK protein induces a slowly activating voltage-dependent potassium current (Isk). We studied the modulation of this current by altering intracellular cAMP levels and found that the amplitude of Isk is dramatically increased by treatments that raise cAMP levels and decreased by agents that lower cAMP levels. Preinjection of a protein inhibitor of the cAMP-dependent protein kinase blocked the effects of increased cAMP levels. There were no changes in the voltage dependence or kinetics of Isk. Mutations that eliminate a potential phosphorylation site on the minK protein did …


The Costs Of Female Choice In A Lekking Bird, Robert M. Gibson, Gwendolyn C. Bachman Jan 1992

The Costs Of Female Choice In A Lekking Bird, Robert M. Gibson, Gwendolyn C. Bachman

School of Biological Sciences: Faculty Publications

We investigated the costs of active female choice in sage grouse, Centrocercus urophasianus, a lekking species in which females make repeated, lengthy visits to leks to assess males before mating. Several potential costs were measured by monitoring changes in hens' ranging behavior, time budgets, and encounter rates with predators when they visited leks. Two costs were identified: hens moved further per day and encountered golden eagles, Aquila chrysaetos, more frequently when visiting leks. However, extra travel due to visiting leks increased predicted daily energetic expenditure by only about 1%, and the risk of predation by golden eagles over …


Individualistic Perspectives On Plant Competition, Nancy J. Huntly Jan 1992

Individualistic Perspectives On Plant Competition, Nancy J. Huntly

Biology Faculty Publications

No abstract provided.


Effects Of Induced Cold Torpor And Hypoxia On Cardiac Mitochondrial Cytochrome Oxidase Activity, Phospholipid Content And Ultrastructure In The Fresh Water Turtle, Pseudemys Scripta, George Demos Jan 1992

Effects Of Induced Cold Torpor And Hypoxia On Cardiac Mitochondrial Cytochrome Oxidase Activity, Phospholipid Content And Ultrastructure In The Fresh Water Turtle, Pseudemys Scripta, George Demos

Master's Theses

No abstract provided.


The Effects Of Ingested Carbonation On Oxygen Transport And Ventilation In Trained Distance Runners, Stacy Jean Ingraham Jan 1992

The Effects Of Ingested Carbonation On Oxygen Transport And Ventilation In Trained Distance Runners, Stacy Jean Ingraham

Dissertations and Theses @ UNI

The purpose of this study was to examine the effect of consumption of carbonated beverages on maximal aerobic capacity, as measured by maximal oxygen consumption (VO2MAX), and respiratory physiology, as measured by ventilation frequency (f), ventilatory equivalent for oxygen and carbon dioxide (O2VE, co2VE), expired minute ventilation (VE), carbon dioxide output (VCO2), respiratory exchange ratio (RER), and tidal volume (VT).

Thirteen male high school, collegiate and post collegiate distance runners from the local community performed two maximal treadmill tests exactly one week apart, following two different fluid ingestion treatments. The subjects were randomly assigned to a carbonated beverage or noncarbonated …


Microbeam Studies Of The Sensitivity Of Structures Within Living Cells, L. A. Braby Dec 1991

Microbeam Studies Of The Sensitivity Of Structures Within Living Cells, L. A. Braby

Scanning Microscopy

Determining the biological effects of low doses of radiation with high linear energy transfer (LET) is complicated by the stochastic nature of charged-particle interactions. Populations of cells exposed to very low radiation doses contain a few cells which have been hit by a charged particle, while the majority of the cells receive no radiation damage. At somewhat higher doses, a few cells receive two or more events. Because the effects of damage produced by separate events can interact in the cell, we have had to make assumptions about the nature of these interactions in order to interpret the results of …


The Microvasculature Of Human Oral Mucosa Using Vascular Corrosion Casts And India Ink Injection I. Tongue Papillae, Q. X. Yu, W. Ran, K. M. Pang, H. P. Philipsen, J. Theilade, X. H. Chen, Y. C. Mok Dec 1991

The Microvasculature Of Human Oral Mucosa Using Vascular Corrosion Casts And India Ink Injection I. Tongue Papillae, Q. X. Yu, W. Ran, K. M. Pang, H. P. Philipsen, J. Theilade, X. H. Chen, Y. C. Mok

Scanning Microscopy

The microvasculature of human tongue papillae originating from 9 males and 6 females, aged 0.5 to 2 years was studied by scanning electron microscopy (SEM) of vascular corrosion casts and by light microscopy (LM) of India ink injected specimens. All papillae showed a microvasculature characterized by primary, secondary and tertiary capillary loops. In the filiform papillae the loops were generally arranged in a corolla-like pattern with the tertiary loops demonstrating a hair-pin shape. The fungiform papillae showed basically a similar architectural pattern although the loops were somewhat more compact and complex in structure. A small, shallow depression of the tertiary …


Tooth Tissues Of Certain Sharks And Lungfishes, Yasutomo Iwai-Liao, Yoshikage Higashi, Yoshitaka Tamada Dec 1991

Tooth Tissues Of Certain Sharks And Lungfishes, Yasutomo Iwai-Liao, Yoshikage Higashi, Yoshitaka Tamada

Scanning Microscopy

A comparative odontologic study was conducted on teeth and their supporting tissues from extant sharks, fossil sharks, and living lungfishes using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) X-ray microprobe to investigate evolutionary changes in tooth structure of the fishes.

No histological differences between the extant and fossil teeth of lamnoid sharks were observed. The weight percent of calcium in osteodentin of the fossil shark was higher than that in the extant shark. The weight percents of both P and Ca of tooth tissues in the giant extinct shark showed comparatively low values.

Both the upper and lower …