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2004

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Articles 3841 - 3870 of 3873

Full-Text Articles in Physical Sciences and Mathematics

Seasonal Activity Areas Of Coyotes In The Bear River Mountains Of Utah And Idaho, Glen F. Gantz, Frederick F. Knowlton Jan 2004

Seasonal Activity Areas Of Coyotes In The Bear River Mountains Of Utah And Idaho, Glen F. Gantz, Frederick F. Knowlton

United States Department of Agriculture Wildlife Services: Staff Publications

We studied the seasonal movement patterns and dispersal of coyotes (Canis latrans) in the Bear River Mountains of northern Utah and southern Idaho to determine whether coyotes in this montane region exhibit an altitudinal migration on a seasonal basis. We used 3 locational parameters to assess whether a seasonal altitudinal migration was evident, including overlap in seasonal activity areas, distance between harmonic mean centers of activity, and seasonal differences in mean elevations of locations. Winter and summer activity areas of every mature coyote overlapped, with mean distances between harmonic centers of seasonal activity of 1.5 km (range = 0.4–3.3 km). …


Pest Control: Rodents, Mark E. Tobin, Michael W. Fall Jan 2004

Pest Control: Rodents, Mark E. Tobin, Michael W. Fall

United States Department of Agriculture Wildlife Services: Staff Publications

Rodents are an important and ubiquitous group of mammals that occur as indigenous or introduced species throughout the world. The populations of a relatively few species that live in close association with humans sometimes cause economic damage or become threats to the health of humans or domestic animals. When rodent control efforts are contemplated, the type of problem and the objectives of these efforts should be carefully defined. Successful management of rodent problems depends upon correct identification of the rodent species involved and on obtaining information on the biology, ecology, and behavior of the species in the ecological setting where …


Coyote And Wolf Habitat Use In Northwestern Montana, Wendy M. Arjo, Daniel H. Peltscher Jan 2004

Coyote And Wolf Habitat Use In Northwestern Montana, Wendy M. Arjo, Daniel H. Peltscher

United States Department of Agriculture Wildlife Services: Staff Publications

Being a habitat generalist is an adaptation suategy that has allowed the coyote to expand its range. As wolves reestablish, or are reintroduced, resident populations of coyotes may change habitat use. We compared habitat use between coyotes and wolves in Glacier National Park after successful recolonization by wolves. Two wolf oacks and nine coyotes were monitored from June 1994 throueh June 1997 to determine habitat use in northwestern Montana. Wolves used habitat types within their home ranges in proportion to availability during the winter, but not the summer when more open areas and burned forests were used. Most coyotes used …


Trends In North American Vulture Populations, Michael L. Avery Jan 2004

Trends In North American Vulture Populations, Michael L. Avery

United States Department of Agriculture Wildlife Services: Staff Publications

In recent years, interactions between vultures and human activities have noticeably increased. These interactions include nuisance roosts, damage to homes and businesses, livestock depredation, and collisions with aircraft. One major factor contributing to the upsurge in vulture problems is higher numbers of these birds. Both turkey vultures and black vultures appear to be experiencing major population increases throughout much of their ranges in the United States. During 1990-2002, Christmas Bird Count (CBC) data revealed annual nationwide increases of 1.79% and 5.97% for turkey wltures and black vultures, respectively. Estimates *om Breeding Bird Survey (BBS) data were 1.99% and 4.97% for …


Managing Wolf Depredation In The United States: Past, Present, And Future, Stewart W. Breck, Tom Meier Jan 2004

Managing Wolf Depredation In The United States: Past, Present, And Future, Stewart W. Breck, Tom Meier

United States Department of Agriculture Wildlife Services: Staff Publications

With the successful recolonization and reintroduction of wolves (Canis lupus) in parts of the western United States (Bangs and Fritts, 1996; Bangs et al., 1998) and the natural expansion of wolves in the upper Midwest (Fuller et al., 1992; Thiel, 2001), managing conflicts between wolves and livestock is a growing issue for livestock producers, resource professionals, and the general public (Mech, 1996). Unlike the coyote, (Canis latrans) where a great deal is known regarding the biology and ecology of depredation and methods for managing it (Knowlton et al., 1999), very little is known regarding patterns and processes of wolves preying …


Usda Wildlife Services Image Collection: Creating An Online Database Of Digital Images Using Contentdmtmso Rware, Diana L. Dwyer Jan 2004

Usda Wildlife Services Image Collection: Creating An Online Database Of Digital Images Using Contentdmtmso Rware, Diana L. Dwyer

United States Department of Agriculture Wildlife Services: Staff Publications

Photographic images are valuable assets in wildlife damage management research. Photographs are used in ~resentation.s ~.. u bublicationsw, ehsites. and wsters to illustrate dama-ge mblems. the mcies involved and management solutions. & - 'However, organizing phot&aphic &llecions is time consuming, requires special storage, and locating individual images becomes difficult as collections grow. This article demonstrates the USDA Wildlife Senices Image Collection Database and describes the steps taken in creatingthe database, scanning the images, developing a conwolled vocabulary and metadata, and Internet search screens. The database allows users to search by keyword, +lay search results, and download selected images hectly into …


Relationship Of Raccoon Road-Kill Data To High-Density Marine Turtle Nesting, Richard M. Engeman, Henry T. Smith, William J.B. Miller Jan 2004

Relationship Of Raccoon Road-Kill Data To High-Density Marine Turtle Nesting, Richard M. Engeman, Henry T. Smith, William J.B. Miller

United States Department of Agriculture Wildlife Services: Staff Publications

Four ycars of data from a hiyh-density n~arine turtle nesting hcach at John D. MacArthur Beach Statc Park, Florida wcrc examined along with data on raccoon (Procyon lotor.) ruad-kills from adjaccnt roads, and data on park attendance (as an index of local traffic) to make infcrcnces about raccoon activity patterns relative to turtle ncsting. Raccoon road-kills were found Lo diminish subsiantially during turtle nesting, even though local traffic was constant or increasing. Opossums (Didelphis virginiana). the only other maminal consistcntly foluid as road-kills, did not show a decrease during ti~rtlen esting season, but they are not known as a primary …


Gopherus Berlandieri (Texas Tortoise). Mortality., Richard M. Engeman, Michael J. Pipas, Henry T. Smith Jan 2004

Gopherus Berlandieri (Texas Tortoise). Mortality., Richard M. Engeman, Michael J. Pipas, Henry T. Smith

United States Department of Agriculture Wildlife Services: Staff Publications

No abstract provided.


Using Geographic Information System (Gis) Software To Predict Blackbird Roosting Locations In North Dakota, Ryan L. Wimberly, Tony A. Slowik, H. Jeffrey Homan, Linda B. Penry Jan 2004

Using Geographic Information System (Gis) Software To Predict Blackbird Roosting Locations In North Dakota, Ryan L. Wimberly, Tony A. Slowik, H. Jeffrey Homan, Linda B. Penry

United States Department of Agriculture Wildlife Services: Staff Publications

Cattail stands provide roosting and staging areas for large congregations of blackbirds in North Dakota in late summer and early fall. Since 1991, the U.S. Depamnent of Agriculture, Ammal and Plant Health Inspection Service, Wildlife Services (WS) program has conducted a cattail management program in North Dakota to alleviate blackbird damage to ripening sunflower. To extend the capabilities of the program, a geographical mformation system (GIS) will be incorporated to help WS personnel find blackbird roosts more effectively. We will use the GIs to construct field maps showing the association between areas of moderate to hgh sunilower damage (>5%) …


Propane Exploders And Electronic Guards Were Ineffective At Reducing Deer Damage In Cornfields, Jason M. Gilsdorf, Scott E. Hygnstrom, Kurt C. Vercauteren, Erin E. Blankenship, Richard M. Engeman Jan 2004

Propane Exploders And Electronic Guards Were Ineffective At Reducing Deer Damage In Cornfields, Jason M. Gilsdorf, Scott E. Hygnstrom, Kurt C. Vercauteren, Erin E. Blankenship, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

White-tailed deer (Odocoileus virginianus) cause millions of dollars of damage to agricultural crops annually. We tested the effectiveness of propane exploders and Electronic Guards (Pocatello Supply Depot, Pocatello, Id.) for reducing deer damage in cornfields during the silking–tasseling stage of growth. Track-count indices (F2,7=0.70, P=0.532), corn yields (F2,6=0.14, P=0.873), and estimated damage levels (F2,12=1.45 P=0.272) did not differ between experimental and control fields. The size (F2,11=0.08, P=0.924), location (F2,9=0.30, P=0.750), and percent overlap (F2,9=0.46, P=0.644) of use-areas of radiomarked female deer in the vicinity of experimental fields did not differ among before, during, and after 18-day treatment periods. In a …


Use Of Roadkill Data To Index And Relate Raccoon Activity At A Heavily Predated, High-Density Marine Turtle Nesting Beach, Richard M. Engeman, Henry T. Smith, William J.B. Miller Jan 2004

Use Of Roadkill Data To Index And Relate Raccoon Activity At A Heavily Predated, High-Density Marine Turtle Nesting Beach, Richard M. Engeman, Henry T. Smith, William J.B. Miller

United States Department of Agriculture Wildlife Services: Staff Publications

Four years of data from a high-density marine turtle nesting beach at John D. MacArthur Beach State Park, Florida were examined along with data on raccoon road-kills from adjacent roads, and data on park attendance (as an index of local traffic) to make inferences about raccoon activity patterns relative to turtle nesting. Raccoon road-klls were found to diminish substantially during turtle nesting, even though local traffic was constant or increasing. Opossums, the only other mammal consistently found as road-kills, did not show a decrease during turtle nesting season, but they are not known as a primary predator of turtle nests. …


Leiocephalus Carinatus Armouri (Northern Curlytailed Lizard), Henry T. Smith, Richard M. Engeman Jan 2004

Leiocephalus Carinatus Armouri (Northern Curlytailed Lizard), Henry T. Smith, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

No abstract provided.


Solutions Through Science: Protecting Sunflowers From Blackbirds Jan 2004

Solutions Through Science: Protecting Sunflowers From Blackbirds

United States Department of Agriculture Wildlife Services: Staff Publications

In late summer, large flocks of blackbirds gather in the northern Great Plains to prepare for their strenuous migration to southern wintering grounds in the United States and Mexico. The birds acquire energy for their trip by feasting on energy-rich seeds and berries. Unfortunately for farmers, many of those seeds come from agricultural crops. Red-winged blackbirds, common grackles, and yellow-headed blackbirds cause most of the damage to commercial crops. Sunflower producers in North Dakota, South Dakota, and Minnesota suffer millions of dollars’ worth of losses annually due to blackbirds.

Reducing blackbird damage to sunflower crops continues to be a challenge …


Ninebanded Armadillo (Dasypus Novemcinctus), Michael T. Mengak Jan 2004

Ninebanded Armadillo (Dasypus Novemcinctus), Michael T. Mengak

United States Department of Agriculture Wildlife Services: Staff Publications

Scientists classify armadillos with anteaters and sloths. This tells us that they have poorly developed teeth and limited mobility. In fact, armadillos have small, peg-like teeth that are useful for grinding their food but of little value for capturing prey. No other mammal in Georgia has bony skin plates or a “shell”, which makes the armadillo easy to identify. Just like a turtle, the shell is called a carapace. Armadillos are common in central and southern Georgia and are moving northward. Only one species of armadillo lives in Georgia and the southeastern U.S. However, 20 recognized species are found throughout …


Evaluating The Disparity Of Female Breast Cancer Mortality Among Racial Groups - A Spatiotemporal Analysis, Chiehwen E. Hsu, Holly Jacobson, Francisco Soto Mas Jan 2004

Evaluating The Disparity Of Female Breast Cancer Mortality Among Racial Groups - A Spatiotemporal Analysis, Chiehwen E. Hsu, Holly Jacobson, Francisco Soto Mas

Faculty, Staff and Student Publications

Background The literature suggests that the distribution of female breast cancer mortality demonstrates spatial concentration. There remains a lack of studies on how the mortality burden may impact racial groups across space and over time. The present study evaluated the geographic variations in breast cancer mortality in Texas females according to three predominant racial groups (non-Hispanic White, Black, and Hispanic females) over a twelve-year period. It sought to clarify whether the spatiotemporal trend might place an uneven burden on particular racial groups, and whether the excess trend has persisted into the current decade.

Methods The Spatial Scan Statistic was employed …


Detecting Spatiotemporal Clusters Of Accidental Poisoning Mortality Among Texas Counties, Us, 1980 – 2001, Ella T. Nkhoma, Chiehwen E. Hsu, Victoria I. Hunt, Ann M. Harris Jan 2004

Detecting Spatiotemporal Clusters Of Accidental Poisoning Mortality Among Texas Counties, Us, 1980 – 2001, Ella T. Nkhoma, Chiehwen E. Hsu, Victoria I. Hunt, Ann M. Harris

Faculty, Staff and Student Publications

Background Accidental poisoning is one of the leading causes of injury in the United States, second only to motor vehicle accidents. According to the Centers for Disease Control and Prevention, the rates of accidental poisoning mortality have been increasing in the past fourteen years nationally. In Texas, mortality rates from accidental poisoning have mirrored national trends, increasing linearly from 1981 to 2001. The purpose of this study was to determine if there are spatiotemporal clusters of accidental poisoning mortality among Texas counties, and if so, whether there are variations in clustering and risk according to gender and race/ethnicity. The Spatial …


Transport Of Pesticides Through Soil Columns From Al-Ain Area, United Arab Emirates, Huda Ateeq Al Hassani Jan 2004

Transport Of Pesticides Through Soil Columns From Al-Ain Area, United Arab Emirates, Huda Ateeq Al Hassani

Theses

Proper management of pesticides application in the UAE is greatly lacking, causing waste of resources and environmental concerns due to the excessive use of these chemicals. It has been reported that the rate of pesticides use in UAE reaches about 10 kg/hectare/yr, posing a potential threat to the quality of water in underlying aquifers. Little, however, is known about the mobility of applied pesticides in the UAE subsurface environment and the impact of these pesticides on soil and groundwater quality.

The aim of this study was to gain an understanding of the fate and mobility of pesticides in the UAE …


Xml In Computational Science, George K. Thiruvathukal Jan 2004

Xml In Computational Science, George K. Thiruvathukal

Computer Science: Faculty Publications and Other Works

In this first article in a series about XML in computational science, I present some background and lightweight examples of XML usage, describe some XML component frameworksalong with their purpose and applicability to computational science, and discuss some technical obstacles to overcome for the language to be taken seriously in computational science.


Pperfgrid: A Grid Services-Based Tool For The Exchange Of Heterogeneous Parallel Performance Data, John Jared Hoffman Jan 2004

Pperfgrid: A Grid Services-Based Tool For The Exchange Of Heterogeneous Parallel Performance Data, John Jared Hoffman

Dissertations and Theses

This thesis details the approach taken in developing PPerfGrid. Section 2 discusses other research related to this project. Section 3 provides general background on the technologies utilized in PPerfGrid, focusing on the components that make up the Grid services architecture. Section 4 provides a description of the architecture of PPerfGrid. Section 5 details the implementation of PPerfGrid. Section 6 presents tests designed to measure the overhead and scalability of the PPerfGrid application. Section 7 suggests future work, and Section 8 concludes the thesis.


Groundwater Trends In The Kent-Frankland Sub-Region, Arjen Ryder Jan 2004

Groundwater Trends In The Kent-Frankland Sub-Region, Arjen Ryder

Natural resources published reports

The South Coast Regional Initiative Planning Team (SCRIPT) has divided the South Coast region of Western Australia into six sub-regions. Kent-Frankland covers the catchments of the Frankland, Gordon and Kent' Rivers. Approximately two-thirds (450,000 ha) has been cleared for agriculture. This publication describes the groundwater trends, risk of shallow watertables, and technical feasibility of salinity management on agricultural land.

Soil-landscape zones are spatial units based on geology and geomorphology. Since most groundwater processes in WA are controlled by the geologic and regolith properties, these zones can be used for allocating hydrological attributes, such as groundwater characteristics and trends. The hydrological …


Groundwater Trends In The Esperance Sandplain And Mallee Sub-Regions, John Andrew Simons, A Alderman Jan 2004

Groundwater Trends In The Esperance Sandplain And Mallee Sub-Regions, John Andrew Simons, A Alderman

Agriculture reports

The South Coast Regional Initiative Planning Team (SCRIPT) has divided the South Coast region of Western Australia into six sub-regions. The Esperance Sandplain and Mallee subregions encompass the Esperance agricultural district, which contains about 1.5 million hectares of agricultural land. This publication describes the groundwater trends, risk of shallow watertables, and technical feasibility of salinity management in the soil-landscape zones within the Esperance agricultural district.


Agricultural Sub-Regions Of The Avon River Basin, Paul D. Galloway Jan 2004

Agricultural Sub-Regions Of The Avon River Basin, Paul D. Galloway

Resource management technical reports

This report identifies, describes and locates nine sub-regions within the land cleared for agricultural uses in the Avon River Basin in Western Australia. The sub-regions are: Darling Range; Dale/Upper Avon; Avon Valley; Yealering Lakes; Mortlock; Northern Sandplain; south-east Lakes; Carrabin; Southern Cross. The sub-regions are described in terms of their distinguishing biophysical characteristics of: soils and related original vegetative cover; general topography; surface and sub-surface hyrdological stus; underlying geology; and rainfall and evapotranspiration range. Current dominant land use, economic drivers and land use pressures are identified for each sub-region.


Wheatbelt Waterwise = Saltwise : Gardening Guide, John Colwill, Juana Roe Jan 2004

Wheatbelt Waterwise = Saltwise : Gardening Guide, John Colwill, Juana Roe

Bulletins 4000 -

As a result of agricultural clearing, many country towns are now feeling the effects of rising groundwater and the salt that it carries. Salinity has been identified as Australia’s number one environmental problem. While most people think that salinity means land lost to agriculture, it also poses a serious threat to many country towns. A report for the Department of Agriculture in 2001 highlighted the need for simple and cost-effective salinity management strategies to be adopted in wheatbelt towns. These included water recycling, revegetation and more efficient water use.


Groundwater Trends In The Albany Hinterland Sub-Region, Arjen Ryder Jan 2004

Groundwater Trends In The Albany Hinterland Sub-Region, Arjen Ryder

Natural resources published reports

The South Coast Regional Initiative Planning Team (SCRIPT) has divided the South Coast region of Western Australia into six sub-regions The Albany Hinterland is in the western portion (see Figure 1). It is bounded by the Pallinup River in the east. Stirling Ranges to the north and the Kent River catchment boundary in the west. Two-thirds (580.000 ha) of the sub-region has been cleared for agriculture This publication describes the groundwater trends, risk of shallow watertables, and technical feasibility of salinity management within the agricultural land

Soil-landscape zones are spatial units based on geology and geomorphology. Since most groundwater processes …


High-Q2 Neutral Current Cross Sections In E+ P Deep Inelastic Scattering At √S = 318 Gev, S. Chekanov, M. Derrick, D. Krakauer, J. H. Loizides, S. Magill, S. Miglioranzi, B. Musgrave, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, A. Margotti, A. Montanari, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli Jan 2004

High-Q2 Neutral Current Cross Sections In E+ P Deep Inelastic Scattering At √S = 318 Gev, S. Chekanov, M. Derrick, D. Krakauer, J. H. Loizides, S. Magill, S. Miglioranzi, B. Musgrave, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, A. Margotti, A. Montanari, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli

Faculty Publications

Cross sections for e+ p neutral current deep inelastic scattering have been measured at a center-of-mass energy of √s = 318 GeV with the ZEUS detector at HERA using an integrated luminosity of 63.2 pb -1. The double-differential cross section, d2σ/ dxdQ2, is presented for 200 GeV2 < Q2 < 30 000 GeV2 and for 0.005 < x < 0.65. The single-differential cross sections dσ/dQ2, dσ/dx and dσ/dy are presented for Q2 > 200 GeV2. The effect of Z-boson-exchange is seen in dσ/dx measured for Q2 > 10 000 GeV2. The data presented here were combined with ZEUS e+ p neutral current data taken at √s = 300 GeV and the structure function F2em was extracted. All results agree well with the predictions of the Standard Model.


Influences On The Uptake Of Covenant Mechanisms For Nature Conservation On Private Lands In Australia, Thomas I. Kabii Jan 2004

Influences On The Uptake Of Covenant Mechanisms For Nature Conservation On Private Lands In Australia, Thomas I. Kabii

Theses: Doctorates and Masters

Globally management agreements have emerged as more effective in assuring long-term nature conservation on private land, than regulatory mechanisms alone. Restrictive permanent covenants in particular, which are legally binding management agreements in perpetuity, have been adopted in most States and Territories in Australia. However, there is reluctance among landholders to take them up. Sound understanding of the factors that influence the decisions of landholders regarding the uptake of permanent covenants is important in planning and strategizing for increased covenant uptake. The aim of this thesis is to further this understanding and to support the design of a coordinated covenant mechanism …


A Generalised Feedforward Neural Network Architecture And Its Applications To Classification And Regression, Ganesh Arulampalam Jan 2004

A Generalised Feedforward Neural Network Architecture And Its Applications To Classification And Regression, Ganesh Arulampalam

Theses: Doctorates and Masters

Shunting inhibition is a powerful computational mechanism that plays an important role in sensory neural information processing systems. It has been extensively used to model some important visual and cognitive functions. It equips neurons with a gain control mechanism that allows them to operate as adaptive non-linear filters. Shunting Inhibitory Artificial Neural Networks (SIANNs) are biologically inspired networks where the basic synaptic computations are based on shunting inhibition. SIANNs were designed to solve difficult machine learning problems by exploiting the inherent non-linearity mediated by shunting inhibition. The aim was to develop powerful, trainable networks, with non-linear decision surfaces, for classification …


Contrast Enhancement Of Ultrasound Images Using Shunting Inhibitory Cellular Neural Networks, Murali M. Gogineni Jan 2004

Contrast Enhancement Of Ultrasound Images Using Shunting Inhibitory Cellular Neural Networks, Murali M. Gogineni

Theses: Doctorates and Masters

Evolving from neuro-biological insights, neural network technology gives a computer system an amazing capacity to actually generate decisions dynamically. However, as the amount of data to be processed increases, there is a demand for developing new types of networks such as Cellular Neural Networks (CNN), to ease the computational burden without compromising the outcomes. The objective of this thesis is to research the capability of Shunting Inhibitory Cellular Neural Networks (SICNN) to solve the clarity problems in ultrasound imaging. In this thesis, we begin by reviewing a number of traditional enhancement techniques and measures. Since the entire work of this …


Outcomes Of A Participatory Approach To Interpretive Planning In The Shark Bay World Heritage Area, Western Australia, Kelly J. Chapman Jan 2004

Outcomes Of A Participatory Approach To Interpretive Planning In The Shark Bay World Heritage Area, Western Australia, Kelly J. Chapman

Theses: Doctorates and Masters

This thesis examines a participatory approach to interpretive planning, employed in the Shark Bay World Heritage Area, Western Australia. At the project outset relations between the conservation agency responsible for administering World Heritage and the local community were strained, and complicated by a history of conflict over the World Heritage listing and subsequent management of the area. A participatory approach to interpretive planning was adopted in the hope that doing so would achieve the following: improved relations between polarised stakeholder groups, increased community support for the plan and its implementation, and improved access to the variety of knowledge pools within …


The Distribution Of Radon Concentration In Caves, Arrigo A. Cigna Jan 2004

The Distribution Of Radon Concentration In Caves, Arrigo A. Cigna

International Journal of Speleology

Radon concentration in caves is known to vary within an extremely wide range. Here the distribution of the average values of radon concentration is examined and a power law describing is identified, i.e. radon concentration has a fractal dimension D=1.26. This fact means that concentrations are not grouped around a mean value, a characteristic common to many other phenomena.