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Index To Volume Two, Risk Editorial Board Sep 1991

Index To Volume Two, Risk Editorial Board

RISK: Health, Safety & Environment (1990-2002)

Index for Volume 2 (1991) of the peer-reviewed journal Risk: Issues in Health & Safety.


Table Of Contents, Volume Two, Number Four, Fall 1991, Risk Editorial Board Sep 1991

Table Of Contents, Volume Two, Number Four, Fall 1991, Risk Editorial Board

RISK: Health, Safety & Environment (1990-2002)

Table of contents for the multidisciplinary peer-reviewed journal Risk: Issues in Health & Safety (ISSN: 1073-8673).


Table Of Contents, Volume Two, Number Three, Summer 1991, Risk Editorial Board Jun 1991

Table Of Contents, Volume Two, Number Three, Summer 1991, Risk Editorial Board

RISK: Health, Safety & Environment (1990-2002)

Table of contents for the journal Risk: Issues in Health & Safety (ISSN: 1073-8673)


Call For Papers Editorial Advisory Board Update, Risk Editorial Board Jun 1991

Call For Papers Editorial Advisory Board Update, Risk Editorial Board

RISK: Health, Safety & Environment (1990-2002)

Editorial advisory board update and call for papers.


Regulating Air Toxics In Rhode Island: Policy Vs. Technical Decisions, Julie A. Roque Mar 1991

Regulating Air Toxics In Rhode Island: Policy Vs. Technical Decisions, Julie A. Roque

RISK: Health, Safety & Environment (1990-2002)

Dr. Roqu6 recounts her work as a doctoral candidate at Brown in developing standards for the regulation of airborne carcinogens. Based in part on this experience, she argues that care needs be taken lest those who regulate Risk bury key policy decisions within a mass of often irrelevant technical details.


Table Of Contents, Volume Two, Number Two, Spring 1991, Risk Editorial Board Mar 1991

Table Of Contents, Volume Two, Number Two, Spring 1991, Risk Editorial Board

RISK: Health, Safety & Environment (1990-2002)

Table of contents for the journal Risk: Issues in Health & Safety (ISSN: 1073-8673)


Tree Crops For Profit And Land Improvement, John Bartle Jan 1991

Tree Crops For Profit And Land Improvement, John Bartle

Journal of the Department of Agriculture, Western Australia, Series 4

Western Australian agriculture is deficient in good perennial species. The traditional segregation of agriculture and forestry has diverted attention from commercial wood producing trees as a potential perennial crop. Recently, scientists have made rapid progress in developing tree cropping systems suitable for extensive use in the wetter (more than 600 mm average annual rainfall) areas of the lower south-west. There is potential for a major industry based on fast-growing eucalypts for pulpwood. The foundations for this industry developed from work on agroforestry, forestry sharefarming and salinity control.


Wildlife Corridors In The Wheatbelt, Richard Hobbs, Denis Saunders Jan 1991

Wildlife Corridors In The Wheatbelt, Richard Hobbs, Denis Saunders

Journal of the Department of Agriculture, Western Australia, Series 4

Native vegetation in the Western Australian wheatbelt now persists mostly in small areas that remained uncleared for various reasons. (See 'Remnant vegetation on farms is a valuable resource' on page 43.) On their own, most of these remnant areas are difficult to manage, and too small to retain viable populations of many of the birds and other animals found in the wheatbelt. These patches of vegetation can be linked by wildlife corridors, which may increase the ability of the wildlife to move about and persist in the area


Whole-Farm Planning : Success At Wilgi Creek, Kevin Shanhun Jan 1991

Whole-Farm Planning : Success At Wilgi Creek, Kevin Shanhun

Journal of the Department of Agriculture, Western Australia, Series 4

Ian and Bev Lynch own Wilgi Creek, a 376 ha mixed farming property at West Mount Barker in the 700 mm rainfall zone. In 1983, they started a whole-farm plan to overcome the problems of declining production caused by waterlogging (their biggest problem), salinity and deterioration of the remnant native vegetation. Today, their property is an example of a successful, wholefarm land conservation plan based on agroforestry, timber production, water harvesting and improved pastures.


Revegetating Salt-Affected Land With Shrubs, Ed Barrett-Lennard, Fionnuala Frost, Steve Vlahos, Norm Richards Jan 1991

Revegetating Salt-Affected Land With Shrubs, Ed Barrett-Lennard, Fionnuala Frost, Steve Vlahos, Norm Richards

Journal of the Department of Agriculture, Western Australia, Series 4

The establishment of salt-tolerant shrubs such as saltbush and bluebush on salt-affected land reduces the risk of soil erosion, and can also fit into farm programmes as a profitable enterprise. Salt-tolerant shrubs can be used as forage for sheep in summer and autumn, when the availability of annual pastures is low or annual pastures are just beginning to emerge. This article describes three methods for establishing shrubs on salt-affected land and what affects shrub establishment.


Back Cover Jan 1991

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Index For Volume 98 Jan 1991

Index For Volume 98

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Auxin-Regulated Gene Expression, Tom J. Guilfoyle Jan 1991

Auxin-Regulated Gene Expression, Tom J. Guilfoyle

Journal of the Iowa Academy of Science: JIAS

A number of cDNA clones to independent mRNAs that increase in amount after brief exposure to auxins have been isolated. From soybean, sequenced, and characterized. Increases in mRNA abundance can be detected as early as 2.5 minutes after auxin application to excised elongating regions of soybean hypocotyls. Increased transcription rates on the genes which encode the auxin-responsive mRNAs account, at least partly, for the accumulation of mRNAs. A variety of auxins induce the accumulation of the mRNAs, but other plant hormones have no effect on the mRNA abundance. Some of the genes which encode the mRNAs are clustered in the …


Stimulus Response Coupling In Auxin Action, K. R. Libbenga Jan 1991

Stimulus Response Coupling In Auxin Action, K. R. Libbenga

Journal of the Iowa Academy of Science: JIAS

This paper not available at time of printing.


Lxodes Dammini (Acari, Ixodidae) And Borrelia Burgdorferi In Iowa, Mark G. Novak, Wayne A. Rowley, Kenneth B. Platt, David M. Bartholomew, Michelle D. Senne Jan 1991

Lxodes Dammini (Acari, Ixodidae) And Borrelia Burgdorferi In Iowa, Mark G. Novak, Wayne A. Rowley, Kenneth B. Platt, David M. Bartholomew, Michelle D. Senne

Journal of the Iowa Academy of Science: JIAS

A statewide study to evaluate the presence, distribution and abundance of the deer tick, Ixodes dammini, and the spirochete, Borrelia burgdorfen, in Iowa was initiated in 1989. Six hundred and seventy-one tick collections were received from health professionals, conservation employees and concerned citizens. Additional ticks were obtained by flagging, small mammal trapping and deer checks in selected areas of Iowa. Nine I. dammini were collected in 1989 from seven counties in the eastern half of the state. Six of these were tested for B. burgdorferi and all were negative. Flagging, small mammal trapping and deer checks in eastern Iowa failed …


Radon In Iowa Homes: Results Of Screening Measurements, Laurent Hodges, Lynne Gillette Jan 1991

Radon In Iowa Homes: Results Of Screening Measurements, Laurent Hodges, Lynne Gillette

Journal of the Iowa Academy of Science: JIAS

Homeowner-initiated short-term radon screening measurements in Iowa homes show that only about 30% of the homes have low enough radon levels - below 148 Bq/m (4.0 pC1/L) - that no follow-up measurements are necessary. Over 6 percent of the homes have screening measurements in excess of 740 Bq/m3 (20 pCi/L), a level at which prompt follow-up measurements are recommended. In all parts of the state, the range of radon results extends from low levels (below 37 Bq/m3 = 1 pCi/L) to high levels (above 740 Bq/m3). The average radon results tend to be higher than the …


Front Matter Jan 1991

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Table Of Contents, Volume Two, Number One, Winter 1991, Risk Editorial Board Jan 1991

Table Of Contents, Volume Two, Number One, Winter 1991, Risk Editorial Board

RISK: Health, Safety & Environment (1990-2002)

Table of contents for the journal Risk: Issues in Health & Safety (ISSN: 1073-8673)


Prospectus And Evaluation Copies Available, Additional Coverage In Indices, Risk Editorial Board Jan 1991

Prospectus And Evaluation Copies Available, Additional Coverage In Indices, Risk Editorial Board

RISK: Health, Safety & Environment (1990-2002)

Editorial announcements and news for the inactive journal Risk: Health, Safety & Environment (ISSN: 1073-8673).


Vascular Flora Of Arend's Kettle, Freda Haffner Kettlehole State Preserve, Dickinson County, Iowa, Edwin L. Freese, William J. Platt Jan 1991

Vascular Flora Of Arend's Kettle, Freda Haffner Kettlehole State Preserve, Dickinson County, Iowa, Edwin L. Freese, William J. Platt

Journal of the Iowa Academy of Science: JIAS

Arend's Kettle is a 5 ha glacial landform in Dickinson County, Iowa. The flora of this kettle was studied over two years prior to acquisition by the Nature Conservancy in 1973. The known vascular flora of Arend's Kettle as of 1973 consisted of 299 species, representing 177 genera and 59 families. The vegetation ranged from xeric short grass prairie along the rims of the kettle to mesic prairie along the middle and lower slopes. In the bottom of the kettle, there was a marsh/seasonal pond community that varied greatly in the amount of water present, depending on rainfall within the …


In Search Of A Gibberellin Receptor, Lalit M. Srivastava, Konrad A. Sechley Jan 1991

In Search Of A Gibberellin Receptor, Lalit M. Srivastava, Konrad A. Sechley

Journal of the Iowa Academy of Science: JIAS

Use of tritiated gibberellins ([3H] GA1, [3H] GA4) of high specific activity and purity has allowed the determination of GA-specific binding sites in several plant tissues both in vivo and in vitro. In cucumber hypocotyls and pea epicotyls which have been most investigated the binding of [3H] GA; occurs to soluble proteins. This binding is saturable ('n' =about 30 pmol. Mg-1 soluble protein), of high affinity (KD= about 70 nM), and is competed for by other GA, and derivatives in proportion to their biological activity in these …


Front Matter Jan 1991

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Planting Trees To Control Salinity, Nick Schofield, Phil Scott Jan 1991

Planting Trees To Control Salinity, Nick Schofield, Phil Scott

Journal of the Department of Agriculture, Western Australia, Series 4

Dense tree plantings covering at least 30 per cent of cleared land can lower groundwater levels by two metres or more in 10 years from the time of planting. This sizeable drop can be expected at sites receiving 700 to 800 mm of rain a year. Research by the Water Authority of Western Australia shows the most promising strategy when using trees is to put dense plantings on the discharge zone and on lower to midslopes. This strategy is successful where groundwaters contain less than 30,000 milligrams per litre total soluble salts (TSS).

This article discusses research in the 450 …


The Greening Of Australia, Martine Scheltema Jan 1991

The Greening Of Australia, Martine Scheltema

Journal of the Department of Agriculture, Western Australia, Series 4

Many urban Australians have little understanding of the problems of land degradation because it's an extremely slow process that doesn 't directly influence their day-to-day lives. Understandably, they would have trouble relating to sub-soil compaction, waterlogging, increased soil acidity and salinity. They also have trouble comprehending why fencing according to soil type is an important management tool for farmers, or what role contour banks, drainage systems, the addition of gypsum and planting trees have in reversing land degradation. But given that tree loss "has been at the core of almost every aspect of land degradation in Australia ", and that …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1991

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Iowa's Climate As Projected By The Global Climate Model Of The Goddard Institute For Space Studies For A Doubling Of Atmospheric Carbon Dioxide, E. S. Takle, S. Zhong Jan 1991

Iowa's Climate As Projected By The Global Climate Model Of The Goddard Institute For Space Studies For A Doubling Of Atmospheric Carbon Dioxide, E. S. Takle, S. Zhong

Journal of the Iowa Academy of Science: JIAS

Results of a global climate model that simulates climate under a doubling of atmospheric carbon dioxide (estimated to occur by the latter half of the twenty first century) have been interpolated to Iowa. Summer temperatures under such a doubling are projected to rise by 4 to 7°F (2.2 to 3.9°C) and winter temperatures by 10 to 11° (5.6 to 6.1°C). Estimates of space heating and cooling demands from these data suggest a 30 to 35% decrease in space heat demand and a 200 to 300% increase in space cooling demand. Temperature variability is projected to decrease. Precipitation estimates from global …


Comparison Of Dinitrogen Fixation And Nitrogen Transfer Potentials Of Four Red Clover Cultivars, D. E. Farnham, A. P. Mallarino, W. F. Wedin, I. T. Carlson Jan 1991

Comparison Of Dinitrogen Fixation And Nitrogen Transfer Potentials Of Four Red Clover Cultivars, D. E. Farnham, A. P. Mallarino, W. F. Wedin, I. T. Carlson

Journal of the Iowa Academy of Science: JIAS

The capacity to fix atmospheric N2 and thus reduce the use of N fertilizer is an important reason for including legumes in forage mixtures. Selection for more efficient N2 fixation could improve red clover (Trifolium prateme L.) (RC) production and its contribution to soil fertility. An isotope dilution study was conducted in two greenhouse experiments to compare the N2 fixation and N transfer potentials of three commercial and one experimental RC cultivars. The experimental cultivar APR-8701 was selected for traits related to increased N2 fixation (rate of acetylene reduction, root size and branch number, and nodule …


Annual Report Of The Iowa Academy Of Science, 1990-91, Paul E. Rider Jan 1991

Annual Report Of The Iowa Academy Of Science, 1990-91, Paul E. Rider

Journal of the Iowa Academy of Science: JIAS

Starting in 1976, annual reports have served as a continuing record of the activities of the Iowa Academy of Science. These augment a 100 year history of the Academy which was written in the centennial year of 1975.

This report covers the period from July 1, 1990 to June 30, 1991. It is based on the official records of the Academy (committee reports, Board minutes, correspondence) as well as the recollections, impressions and musings of the author.


Reclaiming Sandplain Seeps Planting Trees, Richard George Jan 1991

Reclaiming Sandplain Seeps Planting Trees, Richard George

Journal of the Department of Agriculture, Western Australia, Series 4

Sandplain seeps affect large areas of agricultural land in Western Australia's eastern and northern wheatbelt and in the Great Southern. These seeps are estimated to account for about 10 per cent of dryland salinity in the agricultural area. Research and field observations show that seeps may be cheaply and quickly reclaimed using various types of drains or small blocks of trees (George 1990). This article discusses results of reclamation methods associated with tree planting on sandplain seeps in the eastern wheatbelt.


Deep Tillage : Keep An Eye On Costs As Well As Yields, Amir Abadi, Andrew Bathgate Jan 1991

Deep Tillage : Keep An Eye On Costs As Well As Yields, Amir Abadi, Andrew Bathgate

Journal of the Department of Agriculture, Western Australia, Series 4

Deep tillage overcomes compaction of sandy soils caused by movement of heavy machinery. Many experiments since 1981 have shown cereal yields improve as a result of deep tillage. However, the increased yield does not necessarily mean more profit when costs are taken into account. To determine the profitability of deep tillage farmers must consider its impact on other farm operations. A whole-farm analysis is needed to accurately determine the increase in profit resulting from deep tillage