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2008

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Studying Gene Function In Caenorhabditis Elegans Using Rna-Mediated Interference, Eleanor M. Maine Jan 2008

Studying Gene Function In Caenorhabditis Elegans Using Rna-Mediated Interference, Eleanor M. Maine

Biology - All Scholarship

The RNA interference (RNAi) method for targeted gene silencing is widely used in Caenorhabditis elegans for large-scale functional genomic studies, analysis of limited gene sets and detailed analysis of individual gene function. The application of RNAi has identified genes that participate in various aspects of development, physiology and cell biology. In addition, RNAi has been used to identify interacting genes and to study functionally redundant genes. This review discusses the various applications of RNAi in C. elegans, focusing particularly on the analysis of developmental processes.

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Sagebrush Steppe: A Story Of Encroachment And Invasion Jan 2008

Sagebrush Steppe: A Story Of Encroachment And Invasion

Joint Fire Science Program Briefs (2007-2012)

Sagebrush steppe has been rapidly changing into woodlands of western juniper and pinyon pine since Euroamerican settlement of the West in the middle of the nineteenth century. The change from the dry scattered shrub and grasslands to woodlands has changed more than plants—it has also changed the fi re regime. Studies have revealed a threshold at which understory plants may not rebound after a disturbance—when trees have reached 40- to 50-percent cover. Disturbance—by fi re and overgrazing—also makes resources such as nutrients and soil water available for weeds to exploit, allowing invasives such as cheatgrass to establish and expand into …

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Testing The Conventional Wisdom: Fuel Management Approaches For The Central Hardwood Region, Jake Delwiche Jan 2008

Testing The Conventional Wisdom: Fuel Management Approaches For The Central Hardwood Region, Jake Delwiche

Joint Fire Science Program Briefs (2007-2012)

It’s not for nothing that Missouri calls itself the “Show Me State.” The name implies a common-sense insistence on seeing the evidence, an interest in seeing the proof. Thus, it is appropriate that an important long-term forestry research project is taking place in Southeastern Missouri. The goal is to test widely held opinions on the role and effectiveness of various forest fuel management strategies. Research results continue to be collected on the effects of overstory thinning and prescribed burning on forest fuelloads, and on using these tools to change the permanent character of the forest itself. The project began in …

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Forecast For The Southern Boreal Forest: An Increasing Incidence Of Severe Disturbance, Elise Lequire Jan 2008

Forecast For The Southern Boreal Forest: An Increasing Incidence Of Severe Disturbance, Elise Lequire

Joint Fire Science Program Briefs (2007-2012)

On Independence Day, 1999, a storm system that originated over the Gulf of Mexico and passed through North Dakota dealt a severe blow to nearly half a million acres of the Superior National Forest in northern Minnesota. The blowdown, or derecho, packed winds exceeding 90 miles per hour and left in its wake downed and damaged trees and a dangerously high fuel load. Nearly half a million acres of forest were affected, primarily in the Boundary Waters Canoe Area Wilderness (BWCAW) and the Gunfl int Trail Corridor, a strip of land in public and private ownership that supports a thriving …

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Pentimento: Fuels Reduction And Restoration In The Bosque Of The Middle Rio Grande, Lisa-Natalie Anjozian Jan 2008

Pentimento: Fuels Reduction And Restoration In The Bosque Of The Middle Rio Grande, Lisa-Natalie Anjozian

Joint Fire Science Program Briefs (2007-2012)

The Middle Rio Grande of New Mexico is the most extensive, remaining bosque, or cottonwood forest in the southwest. Alterations caused by humans—damming and channeling the river, controlling floods, and planting non-native trees—have disrupted the cycles of the earlier ecosystem. Without periodic flooding, native cottonwoods cannot regenerate. Invasive exotic plants such as Tamarisk, also known as salt cedar, and Russian olive have filled in the gaps and open spaces, increased fuel loads, and continue to replace native trees and shrubs after wildfires. Cottonwoods, not a fire-adapted species, are now at risk from wildfire and replacement by invasive plants. An array …

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Behavior Modification: Tempering Fire At The Landscape Level, Lisa-Natalie Anjozian Jan 2008

Behavior Modification: Tempering Fire At The Landscape Level, Lisa-Natalie Anjozian

Joint Fire Science Program Briefs (2007-2012)

With a history of management choices that have suppressed fire in the West, ecosystems in which fire would play a vital role have developed tremendous fuel loads. As a result, conditions are prime for fires to grow large, escape attack measures, and become catastrophic conflagrations that damage watersheds, forest resources, and homes. With a quiver of treatment options, land managers have successfully used prescribed burning and thinning to modify landscapes at the stand level. But planning treatments to modify fuel build up on a patch of forest is vastly different than planning treatments that could modify fire’s spread over larger …

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Fire And Climate In The Inland Pacific Northwest: Integrating Science And Management, Rachel Clark Jan 2008

Fire And Climate In The Inland Pacific Northwest: Integrating Science And Management, Rachel Clark

Joint Fire Science Program Briefs (2007-2012)

Climate is a vital force shaping much of life on Earth. People have long suspected a link between climate and susceptibility of forests to fire. But measuring such a relationship has been challenging without tools capable of taking into account climate, forest structure through space and time, and other variables. Managers and planners who make decisions to maintain forest health need an accurate understanding of how climate is linked to fire regimes, as well as tools to help them do it. Such tools would take complex information and allow it to be accessed in a straightforward and effective way. Don …

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Taking The Guesswork Out Of Lightning-Caused Wildfire, Marjie Brown Jan 2008

Taking The Guesswork Out Of Lightning-Caused Wildfire, Marjie Brown

Joint Fire Science Program Briefs (2007-2012)

Lightning is a natural source of wildfi re ignitions and causes a substantial portion of large wildfi res across the globe. Simple predictions of lightning activity don’t accurately determine fi re ignition potential because fuel conditions must be considered in addition to the fact that most lightning is accompanied by signifi cant rain. Fire operations managers need improved tools for prediction of widespread dry thunderstorms, which are those that occur without signifi cant rainfall reaching the ground. It is these dry storms that generate lightning most likely to result in multiple fi re ignitions, often in remote areas. In previous …

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How Does A Sierran Forest Grow? Fire, Thinning, And Regenerating Trees, Lisa-Natalie Anjozian Jan 2008

How Does A Sierran Forest Grow? Fire, Thinning, And Regenerating Trees, Lisa-Natalie Anjozian

Joint Fire Science Program Briefs (2007-2012)

Excluding fi re over the last century has allowed canopy cover to burgeon, to thicken, along with litter depth (dead needles and leaves accumulated on the forest fl oor), and tree density in western forests. These changes have altered the small scale (microsite) conditions that affect the ability of tree seedlings to establish. This study in a mixed-conifer forest in the Sierra Nevada revealed relationships between established understory trees and microsite quality, and examined the effect of fi re, thinning, and shrub cover on seedling establishment. Most of the conifer species grew on microsites with relatively high soil moisture and …

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Fire Is For The Birds In Northern Mixed-Grass Prairie, Marjie Brown Jan 2008

Fire Is For The Birds In Northern Mixed-Grass Prairie, Marjie Brown

Joint Fire Science Program Briefs (2007-2012)

Roughly 25,000 acres of grassland in the National Wildlife Refuges of North Dakota and eastern Montana are treated every year with prescribed fi re, mostly on northern mixed-grass prairie. Although this shrinking ecosystem is fi readapted, there have been very few studies of the effects of prescribed fi re on wildlife, introduced and native plants, and wildlife-habitat relationships in this delicate ecosystem. For this project, researchers documented short- and long-term fi re effects on abundance, productivity, nest site selection and nest predation in migratory birds, especially grassland songbirds. They also measured the impacts of encroaching woody shrubs and trees on …

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Something In The Air: Climate, Fire, And Ponderosa Pine In Southwestern Colorado, Lisa-Natalie Anjozian Jan 2008

Something In The Air: Climate, Fire, And Ponderosa Pine In Southwestern Colorado, Lisa-Natalie Anjozian

Joint Fire Science Program Briefs (2007-2012)

Strong, abrupt climate changes on a time scale of annual to decadal length, can have widespread and long-lasting effects on forest communities. Climate affects forests by creating conditions that kill trees through severe drought, or that promote tree establishment during rainy periods that foster seedlings and saplings. Climate also affects disturbance events that produce the conditions that allow, or limit, fi re occurrence. In studying a ponderosa pine forest in southwestern Colorado, scientists found few trees older than a regional “megadrought” that lasted over two decades in the late 1500s. In the 1600s, a long rainy period allowed trees to …

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Searching, Witnessing, Testing: Plants And Fire In Southern California, Lisa-Natalie Anjozian Jan 2008

Searching, Witnessing, Testing: Plants And Fire In Southern California, Lisa-Natalie Anjozian

Joint Fire Science Program Briefs (2007-2012)

Scant knowledge exists on how threatened, endangered, and sensitive (TES) plants on wildlands in southern California respond to fire. With little information to go on, land managers face diffi culties in deciding when to apply prescribed fire as a fuel reduction tool in sensitive habitats. By looking at the postfire landscape of the Manter Fire in the southern Sierra Nevada, which shares rare species with mountains farther south, scientists found the dramatic and dynamic effect of fire on short term recovery. Profuse wildflower displays and other annuals thrived in the first two years postfire, then diminished. Perennials persisted, including previously …

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The Impossible Summer Burn: Techniques For Fuel Reduction, Habitat Restoration And Happy Locals In Northeastern Pine Barrens, Marjie Brown Jan 2008

The Impossible Summer Burn: Techniques For Fuel Reduction, Habitat Restoration And Happy Locals In Northeastern Pine Barrens, Marjie Brown

Joint Fire Science Program Briefs (2007-2012)

New England pine barrens are highly fl ammable, fi re dependent and critically imperiled ecosystems. The last remaining pockets of this vegetation type are woven through cherished historic sites, prestigious resort communities and some of America’s most popular seashores. Fire exclusion has all but eliminated the periodic fi res this landscape requires for rejuvenation and maintenance. Unlike many other wildland-urban interface regions however, there are no regular, high profi le wildfi res to serve as reminders of the urgent need for fuels management. Because fi res are so infrequent, local governments, residents and visitors tend to think of wildfi re …

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Beetles And Severe Fire: Who’S On First? A Century Of Disturbance In Colorado’S Subalpine Forests, Marjie Brown Jan 2008

Beetles And Severe Fire: Who’S On First? A Century Of Disturbance In Colorado’S Subalpine Forests, Marjie Brown

Joint Fire Science Program Briefs (2007-2012)

Forests have evolved with and depend on natural cycles of wildfire, insect outbreaks, disease, and extreme weather for periodic rejuvenation. The subalpine forests of northwestern Colorado experienced an unusual sequence of disturbances in succession over the past 125 years. Severe wildfi res in 2002 were preceded by stand-replacing fi res a century before. These were followed by a record setting wind blowdown, subsequent salvage logging, and two separate bark beetle infestations. This study by University of Colorado researchers was the first to collectively analyze how a century of disturbances interacted with each other to shape ecosystem patterns and processes with …

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The Cone Fire: A Chance Reckoning For Fuel Treatments, Lisa-Natalie Anjozian Jan 2008

The Cone Fire: A Chance Reckoning For Fuel Treatments, Lisa-Natalie Anjozian

Joint Fire Science Program Briefs (2007-2012)

In late September 2002, an accidental fire ignited on Blacks Mountain in the dry pine forest of the Cascade Range of northeastern California. The fire burned through the Blacks Mountain Experimental Forest where a large-scale, long-term study was already underway to test ecological responses to two different stand structures the scientists had created using various treatments: high diversity, with and without prescribed fire, and low diversity, with and without prescribed fire. The study was not originally designed to test the effects of severe wildfires. The Cone Fire created an opportunity to evaluate the effects of different treatments on tree survival …

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The Tao Of Treating Weeds: Reaching For Restoration In The Northern Rocky Mountains, Lisa-Natalie Anjozian Jan 2008

The Tao Of Treating Weeds: Reaching For Restoration In The Northern Rocky Mountains, Lisa-Natalie Anjozian

Joint Fire Science Program Briefs (2007-2012)

Noxious weeds are a serious problem that is spreading across the West. Herbicides such as Picloram have proven to be powerful tools in reducing weed invaders, although use of this tool has often produced unintended consequences. Broadleaf herbicides kill forbs, such as the noxious knapweed, but also harm native forbs such as arrowleaf balsamroot. Removing weedy forbs from a landscape creates opportunities for grasses to thrive—native as well as nonnative. Because of herbicide treatment, study sites experienced great increases in cheatgrass, a non-native grass of poor forage that also alters fire intensity and frequency. Managers should consider that efforts to …

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Keep The Home Fires Burning: Rare Birds And Better Abodes In Southeastern Arizona, Lisa-Natalie Anjozian Jan 2008

Keep The Home Fires Burning: Rare Birds And Better Abodes In Southeastern Arizona, Lisa-Natalie Anjozian

Joint Fire Science Program Briefs (2007-2012)

The buff-breasted fl ycatcher is a rare bird that inhabits forests of the southwestern U.S. Long-term fire exclusion in these forests may have contributed to the buff-breasted fl ycatcher’s historical range contraction and recent population declines. Buff-breasted flycatchers today use less than 10% of their former U.S. breeding habitat. Researchers from the University of Arizona surveyed buff-breasted flycatchers along previously surveyed and new survey routes, some of which had burned during recent wildfires, within nine mountain ranges in southeastern Arizona. Sixty-three percent of the previously surveyed routes showed negative trends, a 10.5% annual decline in buff-breasted flycatcher numbers. Buffbreasted fl …

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In A Ponderosa Pine Forest, Prescribed Fires Reduce The Likelihood Of Scorched Earth, Elise Lequire Jan 2008

In A Ponderosa Pine Forest, Prescribed Fires Reduce The Likelihood Of Scorched Earth, Elise Lequire

Joint Fire Science Program Briefs (2007-2012)

The Malheur National Forest is located in the Blue Mountains on Oregon’s eastern side, the portion of the state that lies east of the Cascade Crest. In the mid 1990s, researchers and land managers conceived a suite of experiments to explore the effects of prescribed fi re on forest health. The studies were designed to coincide with prescribed burns conducted by the USDA Forest Service. The experiments took place in the Emigrant Creek Ranger District, a remote area dominated by ponderosa pine. One of the research projects aimed to assess soil health after different intervals of fire frequency and in …

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When Chaparral And Coastal Sage Scrub Burn: Consequences For Mammals, Management, And More, Rachel Clark Jan 2008

When Chaparral And Coastal Sage Scrub Burn: Consequences For Mammals, Management, And More, Rachel Clark

Joint Fire Science Program Briefs (2007-2012)

The massive Cedar and Otay fires of 2003 in southern California offered researchers an unexpected opportunity to examine the effects of fi re on mammal communities. Jay Diffendorfer and his colleagues had already been sampling small mammal communities at the Rancho Jamul Ecological Reserve where the Otay fi re broke out. There the researchers could see the difference in small mammal communities, pre- and postfire and the impacts of postfire, exotic grass invasion. At the Cleveland National Forest, where the Cedar fire occurred, the team examined whether the size and severity of the fire affected small mammal communities, as well …

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Fire And Ice: Fire Severity And Future Flammability In Alaskan Black Spruce Forests, Marjie Brown Jan 2008

Fire And Ice: Fire Severity And Future Flammability In Alaskan Black Spruce Forests, Marjie Brown

Joint Fire Science Program Briefs (2007-2012)

In Alaska, the unusually warm, dry summer of 2004 brought wildfires that burned a record setting 6.7 million acres, mostly in the flammable black spruce forests of the interior. Less fl ammable deciduous tree species were known to sometimes replace black spruce in areas where fire was severe enough to burn away the organic layer. Based on study of the 2004 fires, researchers developed methods for measuring the depth of pre-fi re organic layers, and predicting patterns of post-fire regeneration and future forest flammability. They investigated how variations in site moisture and organic layer consumption affect subsequent patterns of postfi …

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Have It Your Way: Open Source Software Brings Common Ground To Smoke Management And Emissions Inventories, Marjie Brown Jan 2008

Have It Your Way: Open Source Software Brings Common Ground To Smoke Management And Emissions Inventories, Marjie Brown

Joint Fire Science Program Briefs (2007-2012)

The Fire Emissions Production Simulator (FEPS) is an open source, user—friendly computer program designed for a wide range of users. The software manages data about consumption, emissions, and heat release characteristics of wildland fires and prescribed burns on an hourly basis. Designed for easy use by anyone with a working knowledge of Microsoft Windows applications, FEPS allows users with differing objectives, backgrounds and experience to come to scientifi cally sound, quantitative agreement regarding the emissions impacts of a given fire scenario. It incorporates fuels data from the most popular fuelbeds in the Fuel Characteristic Classifi cation System and fuel models …

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Chainsaws Or Driptorches: How Should Fire Risk Be Reduced?, Valerie Rapp Jan 2008

Chainsaws Or Driptorches: How Should Fire Risk Be Reduced?, Valerie Rapp

Joint Fire Science Program Briefs (2007-2012)

Forest managers have a standard set of tools they use to reduce fire hazard: mechanical thinning, brush clearing, mechanical treatment of slash (small woody debris), prescribed fire, and various combinations and timings of the use of these tools. Although these tools are widely used, the science is sketchy on the benefits and tradeoffs of the different treatments. In response, the national Fire and Fire Surrogates Study (FFS) set up a national network of research sites to study the effects of fire “surrogates,” such as mechanical thinning, mechanical slash treatments, and prescribed fire on forests. Early findings for the Sierra Nevada …

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Earth And Fire: Forests Rely On Healthy Soils For A Well-Rounded Diet, Elise Lequire Jan 2008

Earth And Fire: Forests Rely On Healthy Soils For A Well-Rounded Diet, Elise Lequire

Joint Fire Science Program Briefs (2007-2012)

Historically, frequent low-intensity, dormant-season fire shaped the landscape across a variety of forests in the United States, from eastern hardwood and hardwood/conifer mixtures to western coniferous forests. Decades of fire exclusion have resulted in heavy fuel loads and increased threat of severe wildfire compared to historic conditions in most forest types and also resulted in changes in forest composition compared to historic conditions. The Fire and Fire Surrogates Study (FFS) is the first to apply a standard experimental design to compare thinning, thinning followed by prescribed fire, and prescribed fire alone across a wide spectrum of ecological and economic variables. …

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Synthesis Of Knowledge Of Hazardous Fuels Management In Loblolly Pine Forests, Douglas J. Marshall, Michael Wimberly, Pete Bettinger, John Stanturf Jan 2008

Synthesis Of Knowledge Of Hazardous Fuels Management In Loblolly Pine Forests, Douglas J. Marshall, Michael Wimberly, Pete Bettinger, John Stanturf

Joint Fire Science Program Synthesis Reports

This synthesis provides an overview of hazardous fuels management in loblolly pine (Pinus taeda) forests, as well as a reference guide on prescribed burning and alternative fuel management treatments. Available information is presented on treatment feasibility, approximate costs, and effects on soil, water quality, and wildlife. The objectives of fuel management in loblolly pine forests are to reduce the density of some targeted plant vegetation and change the structural condition of the forest, or both. Prescribed burning is the most common tool for managing fuels in the South due to the relatively low cost per acre and the ability to …

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Synergistic Effects Of Climate-Related Variables Suggest Future Physiological Impairment In A Top Oceanic Predator, Rui Rosa, Brad A. Seibel Jan 2008

Synergistic Effects Of Climate-Related Variables Suggest Future Physiological Impairment In A Top Oceanic Predator, Rui Rosa, Brad A. Seibel

Biological Sciences Faculty Publications

By the end of this century, anthropogenic carbon dioxide (CO2) emissions are expected to decrease the surface ocean pH by as much as 0.3 unit. At the same time, the ocean is expected to warm with an associated expansion of the oxygen minimum layer (OML). Thus, there is a growing demand to understand the response of the marine biota to these global changes. We show that ocean acidification will substantially depress metabolic rates (31%) and activity levels (45%) in the jumbo squid, Dosidicus gigas, a top predator in the Eastern Pacific. This effect is exacerbated by high …

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Evolutionary Divergence In The Feeding Mechanism Of Fishes, Cheryl A.D. Wilga Jan 2008

Evolutionary Divergence In The Feeding Mechanism Of Fishes, Cheryl A.D. Wilga

Biological Sciences Faculty Publications

After the divergence of chondrichthyans and teleostomes, the structure of the feeding apparatus also diverged. Hyoid morphology varies considerably among fossil and extant elasmobranchs and has been hypothesized to be related to feeding style. How hyomandibular morphology affects function during feeding is of great interest since hyoid movement is a key component in the feeding mechanism. Cranial kinematics and buccal pressure during feeding was quantified in elasmobranchs and teleostomes. The feeding mechanism in elasmobranchs with anterior (AHY) or lateral (LHY) directed hyomandibulae differs from teleostomes primarily in hyoid movements due to morphological constraints. The hyoid expands ventrally during feeding in …

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Olininfo, January 2008, Olin Library Jan 2008

Olininfo, January 2008, Olin Library

OlinInfo

Newsletter of the Franklin W. Olin Library at Rollins College

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Actions Memo January 2008, Kutztown University Curriculum Committee Jan 2008

Actions Memo January 2008, Kutztown University Curriculum Committee

UCC Action Memos

No abstract provided.

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Making Research Guides More Useful And More Well Used, Michal Strutin Jan 2008

Making Research Guides More Useful And More Well Used, Michal Strutin

Staff publications, research, and presentations

In summer 2008, a small group of Santa Clara University librarians were charged with exploring ways of making online library research guides more user friendly and interactive. In order to know how to enhance our guides, we first asked the question, "What makes a research guide useful?" What follows is a detailed process of discovery. The process started with literature on guides, which suggests that research guides, particularly general subject guides, are not well used. Examining statistics for science guides supports the contention that course-specific guides are the most well used. Interviews with students told what they look for in …

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We All Teach The Nature Of Science - Whether Accurately Or Not, Michael P. Clough Jan 2008

We All Teach The Nature Of Science - Whether Accurately Or Not, Michael P. Clough

Iowa Science Teachers Journal

The phrase “nature of science” (NOS) is often used in referring to issues such as what science is, how it works, the assumptions underlying the doing of science, how scientists operate as a social group and how society itself both influences and reacts to scientific endeavors. These and many other thoughts regarding the NOS are informed by contributions from several disciplines including, but not limited to, the history, philosophy, sociology, and psychology of science.

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