bluuebunny/crossref_metadata_2025 huggingface dataset:
Forming Academic Identities: Accommodation without Assimilation among Involuntary Minorities
Authors: Hugh Mehan Professor, Coordinator  , Lea Hubbard Graduate Student  , Irene Villanueva Supervisor, Lecturer
Published: May 2005

Institutional mechanisms influence students' ideology, which in turn has a positive influence on their academic performance. Latino and African American students who have participated in an untracking program for their high school careers develop a critical consciousness about their educational and occupational futures. The Latino and African American students in this untracking program become academically successful without losing their ethnic identity. They adopt the strategy of “accommodating without assimilating,” a pattern that Gibson associates with voluntary minorities but not involuntary minorities.
Texts, Social Relations, and Work‐based Skepticism about Schooling: An Ethnographic Analysis
Authors: Deborah Mayne Brandau Reading Specialist, Coordinator  , James Collins Associate Professor, Director
Published: May 2005

The connection between schooling, work, and language has grown increasingly problematic in recent decades. This article explores that connection, addressing certain debates about cultural mismatch, social reproduction, and school resistance, while presenting an ethnographic analysis of school and community in a rural Northeastern setting. The analysis shows a disjunction between schooling and adult work and between schooling and experiences with literature, challenging the school's self‐understood mission.
Russian Refugee Families: Accommodating Aspirations through Education
Authors: Delgado‐Gaitan Concha
Published: May 2005

Historically, new immigrants to the United States have learned to conform to the new society largely through their experiences in the American educational system. The Russian refugee families in one city illustrate how this group with political‐refugee status learns coping strategies through support from community educational programs. Religious and social networks support their efforts to accommodate. New practices in new cultural settings are discussed in this article, as we observe Russian families realize some of their goals while they strive to make sense of obstacles to other aspirations.
Interactional Style and Nonverbal Meaning: Mazahua Children Learning How to Be Separate‐But‐Together
Authors: Paradise Ruth
Published: May 2005

Young children's experience with nonverbally organized social interaction constitutes a primary kind of enculturation. As they acquire the ability to participate in everyday interactions, they simultaneously learn the cultural meanings embedded in them. This article describes the acquisition by Mazahua children of a separate‐but‐together interactional style. An appreciation of the nonverbal meanings involved can further our understanding of the nature of culturally defined interactional styles and their impact on school learning.
Literacy, Social Movements, and Class Consciousness: Paths from Freire and the São Paulo Experience
Authors: del Pilar O'Cadiz María , Torres Carlos Alberto
Published: May 2005

During a socialist administration in São Paulo, Brazil, from 1989 to 1992, a movement for literacy training of youths and adults (MOVA) and for a curriculum reform was established in the city's elementary schools. This article describes the socialist educational projects and Freire's work in São Paulo. It provides both a theoretical discussion of the projects' Freirean premises and a narrative of the experience of a particular group of literacy learners in one São Paulo favela (shantytown). The authors demonstrate a special concern for the articulation between the public sector (i.e., a government agency) and various social movements, as manifested in the MOVA literacy movement. The conclusion calls for “long life” to the creative imagination that inspires and propels such projects of education for social change.
From Lay Teachers to University Students: The Path for Empowerment through Culturally Based Pedagogical Action
Authors: Lima Elvira Souza , Gazzetta Marineusa
Published: May 2005

Empowerment is becoming a fairly common theme of discussion in the education literature in many countries. In Brazil this theme has been relevant for over 30 years and has survived 20 years of dictatorship. From nonformal education to popular education to innovations within the formal system of education, our experience reveals that to provide situations to empower people through educational development is a complex activity. It demands more than giving people the time and space to express themselves as it was considered initially. Though expressing oneself is an important component of a process of empowerment, it cannot be accounted for as the main or only component. Empowerment depends greatly on oriented reflective action. In order to develop autonomy each individual must have knowledge about the instruments and processes through which one gains a voice in a given society. A successful example of empowerment through formal education is presented in order to illustrate the recent developments of culturally based pedagogy in Brazil.
Changing the Culture of Schooling: Navajo and Yup'ik Cases
Authors: Lipka Jerry , McCarty Teresa L.
Published: May 2005

Here we present two cases in which indigenous teacher groups are transforming the culture of schooling. Working within a community school and on the margins of schooling, Navajo teachers at Rough Rock and Yup'ik teachers and elders in southwestern Alaska are finding creative ways to use their culture, their knowledge, and their language in the construction of curriculum and pedagogy. These teacher groups have created zones of safety in which resistance to conventional practices can be expressed and innovative approaches to schooling investigated and practiced. The work of these teacher groups has theoretical implications for community‐based teacher preparation. The challenge remains in transferring these cultural creations to the wider institution of schooling.
And Marvin Raised His Hand: Practices That Encourage Children's Classroom Participation
Authors: Statzner Elsa L.
Published: May 2005

This article discusses teaching practices that foster student involvement. It highlights one marginalized child's transformation into a participant in a Spanish classroom in an urban, multiethnic school setting. Selected student experiences as well as the Spanish teacher's practices and beliefs are described and analyzed within a Freirean framework.
Consejos: The Power of Cultural Narratives
Authors: Delgado‐Gaitan Concha
Published: May 2005

Consejos, cultural narratives, conveys the Estrada family's feelings, perceptions, actions, and responses to the educational system. The Estrada family's story of is one of persistence and love when dealing with schools. Their practice of consejos represents an eight‐year span of time in which conversations with the Estradas illustrated the family's force in the power relations that exist between families and schools in Carpinteria. The concept of consejos spotlights how, in spite of the perceived powerlessness on the part of Mexican immigrant families against the schools, this cultural practice identifies the family's force and unity in support of one another while challenging the schools' notions of learning. The Estradas are empowered through their consejos, their collective work with other families, and school personnel advocates.
Beyond Language: The Many Dimensions of an ESL Program
Authors: Ernst Gisela
Published: May 2005

This ethnographic study investigated one English‐as‐a‐second‐language (ESL) program for elementary students with as many as 20 native languages represented. The article outlines different dimensions of this language program that are conducive to language‐minority students learning how to succeed in schools. Segments of conversations and narrative vignettes collected during a year‐long ethnographic study illustrate the pedagogical assumptions, instructional goals, and organizational arrangements of this ESL program.
Marginality, Cultural Brokerage, and School Aides: A Success Story in Education
Authors: Weiss Melford S.
Published: May 2005

This article will relate one of our more insightful interdisciplinary concepts—the marginal individual as cultural broker—to the world of public schooling and, in the process, allow us to better comprehend the contributions of a much maligned and misunderstood educational employee, the school aide.
African American Males and Learning: What Discourse in Sports Offers Schooling
Authors: Mahiri Jabari
Published: May 2005

This research investigates language use in a youth basketball program of a neighborhood‐based organization and compares it to features of classroom discourse. The central focus is on a key communicative event, the “coaches circle,” where significant verbal exchanges between children and adults occur. Coach‐player interactions are also contextualized in the mentoring perspective of the program's coaches council. Implications are drawn for extending the teacher‐as‐coach school‐reform model based on considerations of language development and learning in this community sports setting.
Mathematics Practice in Carpet Laying
Authors: Masingila Joanna O.
Published: May 2005

Building upon previous research concerning mathematics practice in everyday situations, this article studies the mathematical concepts and processes used in carpet laying. Mathematics practice in carpet laying is characterized through a discussion of the mathematics used by carpet layers in estimation and installation activities, in an effort to describe and detail how people actively give meaning to and use mathematics in the midst of ongoing activities in relevant settings.
Sense Making across Disciplines: The Spindlers, Adaptation, and the Self That Never Left
Authors: Schram Tom
Published: May 2005

The Psychoanalytic Study of Society, Volume 17: Essays in Honor of George D. and Louise S. Spindler

Edited by L. Bryce Boyer and Ruth Boyer
The Fax, the Jazz Player, and the Self‐Story Teller: How Do People Organize Culture?
Authors: Eisenhart Margaret
Published: May 2005

Theories of how culture affects socialization and the formation of persons have long been of interest to anthropologists of education. In most of these theories, individuals are defined, categorized, shaved, or determined by social practices that reflect cultural priorities. Until recently, few educational anthropologists have given serious consideration to conceptualizing how individuals actively and inventively contribute to cultural continuity or change. Using data collected during an 18‐month workplace ethnography, I suggest that one means by which individuals actively organize culture is through the “stories of self” that they express or enact when they join new social settings. These stories are conceived as devices that mediate changing forms of individual participation (i.e., learning) in context. As such, stories of self contribute to identity formation and affect culture.
Do Not Go Gentle into That Good Night. Rage, Rage, against the Dying of the Light
Authors: Blair Heather , Fredeen Shirley
Published: May 2005

The literature on obsolescent languages provides both helpful and discouraging perspectives. The authors place the circumstances surrounding and the condition of indigenous languages in Western Canada in relation to that found in other parts of the world. Based on sociolinguistic research in Saskatchewan, Canada, a reflection of the significance of language loss for indigenous communities is set forth.
Black University Students in South Africa: The Influence of Sociocultural Factors on Study and Performance
Authors: van Heerden Eulalie
Published: May 2005

Ethnographic research was undertaken to determine which, and how, sociocultural factors influence the academic performance of black students at a distance‐education university in South Africa. A contextual and individualistic‐holistic approach to case studies was applied. Performance was found to be related to various sociocultural and other factors that included: inadequate preparation for schooling, poor conditions and teaching in schools, unfamiliarity with the university's culture of learning, inefficient learning styles, problems with the organization of study and the use of available study time, language difficulties, economic, and physical environmental factors. Underlying these interlinked factors are the politics of apartheid and black cultural ideas and way of life.
“Two Worlds Together”: Contradiction and Curriculum in First Nations Adult Science Education
Authors: Haig‐Brown Celia
Published: May 2005

Examining the applicability of concepts such as cultural discontinuity, acculturation, and cultural therapy, drawn from existing anthropological literature on the process of education and minorities, this article traces the development and implementation of a postsecondary science curriculum for First Nations adult learners. Selected student and teacher responses to the curriculum, gathered as part of a two‐year ethnographic study, are presented. The article argues that an emergent notion of dialectical contradiction, both in the goals of the curriculum plan and in the lived experiences of the students participating with the curriculum, provides a dimension of analysis beyond unidirectional cultural change. Implications for others working in such areas are considered.
Navajo Mothers and Daughters: Schools, Jobs, and the Family
Authors: Deyhle Donna , Margonis Frank
Published: May 2005

Navajo women's historically problematic relation to public schools might be best understood by considering the role that matrilineal networks play in giving Navajo women a place of respect as mothers and daughters—a life course to which schools contribute little. Navajo women's commitment to cooperative family relations is sharply at odds with contemporary educational practice and much educational thought, which assumes the desirability of an individualistic lifestyle and is devoted to helping students adopt a middle‐class orientation.
Constructing and Staffing the Cultural Bridge: The School as Change Agent in Rural Appalachia
Authors: DeYoung Alan J.
Published: May 2005

Rural American schools still educate almost 28 percent of the nation's children, but only educational historians and rural sociologists have paid much attention to issues and dynamics of such places. Here, rural educators often intentionally teach and model national norms, values, expectations, and skills. Such teachings, they allege, are particularly critical to children's successful participation in the national culture, as rural communities typically do not have the types of complementary social or economic institutions that support metropolitan schooling aims. Meanwhile, these schools themselves often continue as targets of state and federal reform efforts since their local tax base often makes them particularly dependent upon outside funding sources. In the following essay I briefly develop a number of these themes. I then illustrate various rural school dynamics and issues with data from a West Virginia school system in which I have been involved in various research capacities during the past five years.
Growing Up Black, Female, and Working Class: A Teacher's Narrative
Authors: Henry Annette
Published: May 2005

This discussion contributes to emergent literature on teacher biographies and on the schooling of black girls. The author examines some childhood experiences of a contemporary woman African‐Caribbean Canadian teacher, Ese, who grew up in England. The author traces the development of Ese's present consciousness by examining how her experiences of marginality at the intersections of her race, gender, and class have informed her current practice in predominantly African Canadian, low‐income settings in southern Ontario. The data are drawn from a larger ethnographic study on black women teachers' lives and practices. Based on her findings, the author concludes with a discussion of future research agendas for young black girls.
Whales Tales, Dog Piles, and Beer Goggles: An Ethnographic Case Study of Fraternity Life
Authors: Rhoads Robert A.
Published: May 2005

Because women continue to be exploited and victimized in fraternity settings, understanding the culture of fraternity life is imperative. This study examines the culture of a fraternity situated at a large research university. Relying on critical views of culture and power, this article highlights how a fraternity continues to reproduce a culture of oppression despite elimination of the traditional pledge process.
Culture as Disability
Authors: McDermott Ray , Varenne Hervé
Published: May 2005

Common sense allows that persons unable to handle a difficult problem can be labeled “disabled.” Social analysis shows that being labeled often invites a public response that multiplies the difficulties facing the seemingly unable. Cultural analysis shows that disability refers most precisely to inadequate performances only on tasks that are arbitrarily circumscribed from daily life. Disabilities are less the property of persons than they are moments in a cultural focus. Everyone in any culture is subject to being labeled and disabled.
Teacher Self‐Identification in Culture from Vygotsky's Developmental Perspective
Authors: Shepel Elina N. Lempert
Published: May 2005

Major changes have taken place in Russian education during the past eight years: new openness, new approaches, new recognition of deficiencies and needs. As teachers sought to throw of the regimentation of the past, they turned to the newly republished works of L. S. Vygotsky and his followers for ideas. This article contrasts the differing perspectives on a number of critical issues in Vygotsky's cultural‐historical theory (zone of proximal development, action/act/activity, element/unit analysis, social situation of development/contextualism). The recent effort to design a teacher developmental education program based on the principles of Vygotsky's cultural‐historical concept put the concept itself in question. The principles of such a program will be discussed, particularly the idea of teacher self‐identification in culture. The aim of this article is to facilitate the debate about these important issues and to define the international perspectives in the development of the cultural‐historical concept.
Culture Revisited: Vygotsky's Ideas in Brazil
Authors: Lima Elvira Souza
Published: May 2005

This article discusses the confluence of the Vygotskian cultural‐historical psychology with the Brazilian school of critical pedagogy and the experiences of alternative schooling in Brazil. It examines the present reform of the public school system in the city of Belo Horizonte and the role of some of Vygotsky's ideas in complementing and expanding the theoretical basis of critical pedagogy and illuminating the historical praxis of the struggle for equity in education. The Brazilian experience of alternative schooling, which already has a long tradition and a wealth of accumulated experience in the 20th century, challenges the traditional notions of school and the narrow views of literacy and learning that lead to the instrumentalization of schooling. Building upon that experience, critical pedagogy developed a comprehensive view of the educational process as one of development and liberation of the total human being and of education for social participation and democratic development. Vygotsky's notions on human development and education bring a new theoretical contribution to the Brazilian experience, which in turn can provide a new perspective for the reading of some of the key concepts of cultural‐historical psychology.
Consensus Construction as a Collective Task in Mexican Science Classes
Authors: Candela Antonia
Published: May 2005

In this article, discourse analysis focuses on the orientation of teachers' and children's classroom discourse toward the construction of a consensual version of science knowledge, even though a consensus is not always reached. This orientation, in which children and teachers shared as active participants the activity's proposals, can be seen as a collective way of developing the zone of proximal development (ZPD) in a cooperative context where the ZPD is the social product of the interaction, rather than the individual effect of the action undertaken by an adult on a child. Discourse orientation toward consensus can be seen as a cultural feature of the interactional dynamics in some school classes in Mexico.
Medicaid Policy Statement
Authors:   Committee on Child Health Financing
Published: May 2005

Medicaid is a vital safety net for children that must be maintained. It is the largest single insurer of children, yet millions of children who are eligible remain unenrolled. Every effort should be made to implement expanded eligibility and streamlined enrollment procedures. Early and Periodic Screening, Diagnosis, and Treatment (EPSDT) benefits should be maintained for all eligible children. On average, Medicaid covers 30% of a pediatrician's patients, yet inadequate reimbursement affects children's access to care. States should increase reimbursement to at least parity with Medicare.
Studies of electron transfer dynamics in particle‐surface interactions
Authors: Esaulov Vladimir A.
Published: May 2005

A review of recent work on electron transfer processes leading to neutralization of positive ions and formation of negative ions is presented. Experiments were performed on simple jellium‐like metal surfaces, transition metals, and specific characteristics of electronic band structure were investigated for some cases, revealing differences in electron transfer processes between surfaces of the same element. It was shown that electronegative adsorbates like oxygen and chlorine provoke strong changes in electron transfer rates, which are akin to promotion and poisoning of reactions at surfaces. The results of experiments on Auger neutralization of He+ ions on Ag surfaces and H− and F− formation on Ag and Pd surfaces are presented and compared with recent theoretical treatments of these processes. The effect of adsorbates is illustrated by the example of chlorine adsorption on silver. Directions where further theoretical effort would considerably advance the understanding of these phenomena are delineated.
Adsorption and nonadiabatic processes in the photodesorption of molecular oxygen from the reduced TiO2 (110) surface
Authors: De Lara‐Castells María Pilar , Mitrushenkov Alexander O. , Roncero Octavio , Krause Jeffrey L.
Published: May 2005

We review the adsorption and desorption of molecular oxygen on a reduced TiO2 (110) surface. This system is known to play a fundamental role in heterogeneous photocatalysis. Periodic calculations are performed with the objective of characterizing the variety of stable species of O2 that are known to exist on the TiO2 surface. The implications of our results for recent experiments are discussed. We also consider a direct optical excitation mechanism for the ultraviolet (UV) light‐desorption process and model the most stable O2/TiO2‐x system as a cluster. High‐level ab initio calculations of the excited states and interaction matrix elements are performed using different orbitals, separately optimized for the target states. The nonadiabatic and dipole‐moment couplings are calculated directly from the correlated wave functions by a special transformation to bi‐orthonormal (dual) orbital sets to preserve their structure. The method used for the electronic structure calculations is described in detail. Finally, the effect of the electronic coupling in the UV‐photodesorption dynamics is analyzed in detail.
Mixed quantum—classical treatment of reactions at surfaces with electronic transitions
Authors: Bach Christian , Carbogno Christian , Gross Axel
Published: May 2005

The reliable high‐dimensional theoretical description of reactions at surfaces with electronic transitions still represents a considerable challenge since the electrons have to be treated quantum mechanically. A full quantum treatment of both electrons and nuclei is computationally not feasible at the moment. Therefore we propose a mixed quantum—classical approach for the simulation of reactions at surfaces with electronic transitions. In this method, the nuclear motion is described classically while the electrons are treated quantum mechanically. Still the feedback between nuclei and electrons is taken into account self‐consistently. The computational efficiency of this method allows a more realistic multidimensional treatment of electronically nonadiabatic processes at surfaces. We will discuss two recent applications of this approach. First we will address the charge transfer in the scattering of I2 from a diamond surface. As a second example we present dynamical simulations of the laser‐induced desorption of NO from NiO(100).
Movements of Lake Trout in U.S. Waters of Lake Superior, 1973–2001
Authors: Kapuscinski Kevin L. , Hansen Michael J. , Schram Stephen T.
Published: May 2005

We analyzed tag–recapture data for lake trout Salvelinus namaycush from the U.S. waters of Lake Superior to determine whether (1) mean movement distance varied among management units, (2) mean movement distance and recapture percentage differed between spawning and nonspawning recapture seasons, (3) percentages of movements to the east and west were similar, and (4) movement distance varied with body length, sex, origin, age, or time at liberty. Mean distance moved by lake trout varied among management units. Mean movement distance was lower for fish recaptured during the spawning season than for fish recaptured during the nonspawning season for three of four tagged populations, and the spatial distribution of recapture percentages differed between recapture seasons. On average, lake trout recaptured during the nonspawning season traveled 42 km while at liberty. Lake trout tagged in two of six management units emigrated to the east and west in equal percentages, but lake trout did not emigrate from the tagging unit to other management units at equal percentages. Movement distance varied significantly with time at liberty for lake trout tagged in one management unit, but did not vary significantly with length, age, time at liberty, sex, or origin for those tagged in other management units. Lake Superior fishery managers can use our results to account for lake trout movements between management units when calculating sustainable harvest levels with catch-at-age modeling.
Effects of the Extent and Duration of Seasonal Flood Pool Inundation on Recruitment of Threadfin Shad, White Crappies, and Largemouth Bass in Hugo Reservoir, Oklahoma
Authors: Boxrucker Jeff C. , Summers Greg L. , Gilliland Eugene R.
Published: May 2005

Our objective was to determine the effects of the extent and duration of seasonal flooding (meters above normal pool) on recruitment indices for threadfin shad Dorosoma petenense, white crappies Pomoxis annularis, and largemouth bass Micropterus salmoides in Hugo Reservoir, Oklahoma. We used simple linear regression to examine the relations between seasonal pool elevation exceedence duration (number of days for which elevation exceeded target values) and (1) mean monthly (June–September) estimates of age-0 threadfin shad abundance in midwater trawls; (2) white crappie abundance estimates from May and June trawl samples and November trap-net samples; and (3) fall electrofishing samples of age-0 largemouth bass. Due to the large number of relations tested, we could not discount the possibility that a significant positive relation between threadfin shad trawl catches in July–September and winter exceedence duration (≥123.8 m) occurred by chance. No relation was found between elevation and age-0 white crappie catch in trawls or trap nets. Summer exceedence duration (≥123.8 m) was positively related to largemouth bass recruitment. The results of this study indicated that a water level management plan that calls for holding water in the flood pool during summer would enhance recruitment of largemouth bass in Hugo Reservoir.
Movement of Black Crappies and Bluegills among Interconnected Lakes in Minnesota
Authors: Parsons Bradford G. , Reed Jeffrey R.
Published: May 2005

The movement of fish among interconnected lakes has been documented for highly mobile species; however, little information is available for black crappie Pomoxis nigromaculatus and bluegill Lepomis macrochirus. We assessed emigration of black crappies from 4 lakes and bluegills from 2 lakes within a chain of 16 lakes in west-central Minnesota by comparing the proportion of angler returns of T-bar anchor tags reported from lakes other than the one in which the fish were tagged. Over a 3-year period, black crappie angler tag returns from nonorigin lakes ranged from 6% to 23% in the four lakes. Annual emigration rates of black crappies ranged from 0% to 92%. For bluegills, the 3-year emigration rate was 9% from Le Homme Dieu Lake and 14% from Victoria Lake, with annual rates ranging from 3% to 36%. We found no evidence that the size of bluegills or black crappies at tagging affected the likelihood of emigration and no evidence that movement upstream or downstream was preferred. Fisheries managers should not consider bluegill and especially black crappie populations in connected lakes to be isolated.
Seasonally Dependent Movement of Lake Trout between Two Northern Idaho Lakes
Authors: Venard Jacob A. , Scarnecchia Dennis L.
Published: May 2005

The diel and seasonal movements of lake trout Salvelinus namaycush between Upper Priest Lake and Priest Lake, Idaho, were studied in 2000. Gill nets were used to capture and detect fish movements between the lakes. Lake trout were caught in the outlet of Upper Priest Lake and in the Thorofare (the narrow channel connecting the two lakes) primarily in the spring and fall, when water temperatures were cool. No lake trout were caught when the water temperature exceeded 15°C. Lake trout were primarily caught at night (94%). Multiple regression analysis indicated that nighttime lake trout catch per unit effort (CPUE) was significantly higher at lower lake surface water temperatures than at higher temperatures (P < 0.01). Daytime lake trout CPUE was significantly higher at low Priest Lake surface temperature than high temperature and at high Thorofare depth than at low depth (P < 0.01). Nighttime CPUE was significantly higher than daytime CPUE (P < 0.01). These results indicate that warm summer water temperatures function as a natural thermal barrier to movement between the lakes in July and August, and that it may be necessary to block lake trout movements between the two lakes at other times to effectively control the population in Upper Priest Lake.
Are Block Nets Necessary?: Movement of Stream-Dwelling Salmonids in Response to Three Common Survey Methods
Authors: Peterson James T. , Banish Nolan P. , Thurow Russell F.
Published: May 2005

Fish movement during sampling may negatively bias sample data and population estimates. We evaluated the short-term movements of stream-dwelling salmonids by recapture of marked individuals during day and night snorkeling and backpack electrofishing. Bull trout Salvelinus confluentus and rainbow trout Oncorhynchus mykiss were captured in sufficient numbers to evaluate instream movements and the influence of stream habitat on movement. Salmonids moved upstream more often than downstream, which suggests that fish fled in response to sampling procedures. Fish movement rates were related to sampling method and stream habitat characteristics. The proportion of bull trout (mean total length, 148 mm) moving upstream from a 50-m reach was 28% for day snorkeling, 25% for night snorkeling, and 18% for single-pass electrofishing. The likelihood of rainbow trout movement upstream during sampling declined as the percentage of rubble substrate increased. Rainbow trout (mean total length, 139 mm) traveled short distances; 67% of mobile rainbow trout traveled 25 m, whereas 59% of mobile bull trout traveled more than 50 m. Our results suggest that fish movement out of sample sites during sampling may negatively bias abundance estimates and positively bias estimates of detection probability. We suggest that block nets are necessary to ensure population closure when estimating population abundance for stream-dwelling salmonids. We further caution that, when fish flee in response to sampling, observations of habitat use may only apply to the proportion of fish that remained stationary and that were observed.
The Influence of Circle Hooks on the Capture Efficiency and Injury Rate of Walleyes
Authors: Jones Thomas S.
Published: May 2005

In fisheries managed with conservative regulations, catch-and-release mortality may contribute over one-half of the total fishing mortality. Popular angling literature suggests that circle hooks reduce hooking mortality by reducing the incidence of deep hooking. Anglers fished for walleyes Sander vitreus with circle hooks and octopus hooks (J-hooks) to explore differences in hook efficiency and injury rate. The strike-specific injury rate (SSIR) was defined as the product of four performance ratings: hooking efficiency (H), retention efficiency (R), deep-hooking rate (D), and internal injury rate (I). The H of circle hooks was significantly less than that of octopus hooks. Values of R, D, and I did not differ significantly between circle hooks and octopus hooks, although all three proportions were lower for circle hooks. The circle hook SSIR was 0.12 injuries/strike and was significantly lower than the octopus hook SSIR of 0.27 injuries/strike. Assuming that hooking mortality is proportional to the rate of internal injury of landed fish (D × I), fishing mortality for walleye fisheries could be lowered by the use of circle hooks. Hooking efficiency, which was important in reducing SSIR, is often overlooked in traditional hooking mortality studies that focus on the survival of released fish. Anglers may be unwilling to accept regulations requiring circle hooks if they perceive that the hooks reduce catch rates while not reducing D and I
Single- versus Multiple-Pass Boat Electrofishing for Assessing Smallmouth Bass Populations in Virginia Rivers
Authors: Odenkirk John , Smith Scott
Published: May 2005

A depletion electrofishing study was conducted on two Virginia rivers to estimate the density and biomass of smallmouth bass Micropterus dolomieu. Population estimates generated by a maximum likelihood analysis (MLM) were compared with those derived by the Leslie method. Also, population size structures from depletion samples were compared with those from single-pass surveys. Adult smallmouth bass were successfully depleted in three to five runs at most sites, and estimates averaged 386/km (SE = 132) and 47/ha (SE = 17) on the Rappahannock River and 265/km (SE = 90) and 38/ha (SE = 20) on the James River. Age-0 population estimates averaged 221/km (SE = 60) and 28/ha (SE = 14) on the Rappahannock River and 248/km (SE = 88) and 31/ha (SE = 14) on the James River. Capture probability was highest (mean = 0.40) for adult bass on the Rappahannock River and lowest (mean = 0.17) for age-0 bass on the James River. Population estimates based on the Leslie method, which regressed catch per effort on cumulative catch (lagged for one run), were greater than those generated by MLM, but the differences were relatively consistent and averaged 25%. Single-pass runs provided biased estimates of size structure at two of four Rappahannock River sites based on total length comparisons of stock size fish and structural indices (more large fish were captured by depletion electrofishing); however, little size selectivity bias existed between methods on the James River. This study suggests that smallmouth bass densities can be successfully estimated from sample reaches within large Virginia rivers and provides cautious optimism that single-pass electrofishing adequately describes smallmouth bass population size structure in some Virginia rivers.
Event or catastrophe in biogeosciences
Authors: Babin Claude
Published: May 2005

Catastrophism is back again into the biogeosciences since the recent hypotheses regarding the mass extinctions but its use has led to some immoderate language. So it would be better to use, according to H. Tintant, the word event. Catastrophe and catastrophism have an anthropocentric echo which doesn’t fit in with the scientific vocabulary.
Yield Response of Corn to Crowding Stress
Authors: Hashemi Abolhassan M. , Herbert Stephen J. , Putnam Daniel H.
Published: May 2005

Plants grown at noncompetitive densities (isolated plants) can be used to relate competitive pressure on yield and yield components at high plant densities. The main objective of this research was to quantify the sensitivity of grain yield and its components to manipulation of crowding stress in corn (Zea mays L.). The experiment was conducted in Deerfield, MA (1986, 1987, and 2000), and Shoush, Iran (1998 and 1999). Three single‐ear corn hybrids were planted at six densities (0.25, 3, 4.5, 6, 9, and 12 plants m−2), the lowest density being considered an isolated density. The higher three densities (6, 9, and 12 plants m−2) were combined with three removal treatments, consisting of removal of alternate plants in rows at different stages of growth. Intensity of competition was quantified by comparing grain yield and its components of plants in these densities with those of isolated plants. The highest grain yield in all experimental sites was obtained from 9 plants m−2 and for total biomass yield between 9 and 12 plants m−2. Kernel yield per plant decreased linearly in all hybrids as plant density intensified. All yield components had a linear decline in response to increased competition pressure. The reduction in kernel yield was attributed most to the reduction in number of kernels per row. Removal treatments indicated that early competition during vegetative growth had no or little effect on final grain yield. Plant competition between the vegetative stage and anthesis had a large effect on grain yield reduction, which ranged from 8 to 21% in different hybrids and experimental sites. Increased assimilate supply through plant removal again confirmed that adjustments in grain yield occurred primarily through kernel number per row.
Remote Sensing the Spatial Distribution of Crop Residues
Authors: Daughtry C. S. T. , Hunt E. R. , Doraiswamy P. C. , McMurtrey J. E.
Published: May 2005

Management of plant litter or crop residues in agricultural fields is an important consideration for reducing soil erosion and increasing soil organic C. Current methods of quantifying crop residue cover are inadequate for characterizing the spatial variability of residue cover within fields and across large regions. Our objectives were to evaluate several spectral indices for measuring crop residue cover using ground‐based and airborne hyperspectral data and to categorize soil tillage intensity in agricultural fields based on crop residue cover. Reflectance spectra of mixtures of crop residues, green vegetation, and soil were acquired over the 400‐ to 2500‐nm wavelength region. High‐altitude AVIRIS (Airborne Visible Infrared Imaging Spectrometer) data were also acquired near Beltsville, MD, in May 2000. Broad absorption features near 2100 and 2300 nm in the reflectance spectra of crop residues were associated with cellulose and lignin. These features were not evident in the spectra of green vegetation and soils. Crop residue cover was linearly related to the cellulose absorption index, which was defined as the relative depth of the 2100‐nm absorption feature. Other spectral indices for crop residue were calculated and evaluated. The best spectral indices were based on relatively narrow (10–50 nm) bands in the 2000‐ to 2400‐nm region, were linearly related to crop residue cover, and correctly identified tillage intensity classes in >90% of test agricultural fields. Regional surveys of soil management practices that affect soil conservation and soil C dynamics may be feasible using advanced multispectral or hyperspectral imaging systems.
Comparison of Phosphorus Uptake from Poultry Litter Compost with Triple Superphosphate in Codorus Soil
Authors: Sikora Lawrence J. , Enkiri Nancy K.
Published: May 2005

Nutrient management plans require that fertilizer equivalents of manures and composts be used in determining the total nutrient application to soils. The P nutrient content of manure composts has not been studied as extensively as N. In a growth chamber study using 15‐cm pots, a Codorus silt loam soil (Fluvaquentic dystrochrepts) with less than 10 mg kg−1. Mehlich‐3 extractable P was amended with poultry litter compost (PLC) or triple superphosphate (TSP) at rates of 0, 25, 50, 100, and 150 kg P ha−1. Nitrogen was supplied to be uniform across all treatments, taking into account the N mineralization rate of PLC. Fescue (Festuca arundinacea Schreb) was grown and harvested three times over 103 d. Yield of fescue was curvilinear related to rate of amendment, but yield was not affected by PLC or TSP. Models describing yield changes with rate were different for TSP and PLC. Phosphorus uptake was statistically the same for both treatments, and a single quadratic equation described P uptake with rate. These data indicate that PLC added to soils on a total P basis provided the same amount of fertilizer equivalents as TSP. The use of composted manure as a N source narrows further the plant available N/P ratio from that recorded in manures because N is immobilized and P is not. To use manure compost as source of P, more fertilizer N would be required to satisfy crops needs than if manure was used as a P source.
Photosynthesis and Nutritive Value in Leaves of Three Warm‐Season Grasses before and after Defoliation
Authors: Mehaffey M. H. , Fisher D. S. , Burns J. C.
Published: May 2005

Forage yields are influenced by plant response to defoliation. We examined the photosynthesis and nutritive value of first (first leaves) and third (third leaves) fully expanded leaves (numbered from the apex) in three warm‐season (C4) grasses. Net photosynthetic rates at uniform temperature and light both before and after a 2‐wk exposure to full sunlight and the effect of leaf position on nutritive value were determined on vegetative tillers in well‐established swards of bermudagrass [Cynodon dactylon L. (Per.) cv. Tifton 44], caucasian bluestem [Bothriochloa caucasica (Trin.) C.E. Hubb.], and Atlantic coastal panicgrass [Panicum amarum var. amarulum (Hitchcock and Chase) P.G. Palmer] growing on a Cecil clay loam (clayey, kaolinitic, thermic Typic Hapludults). Bermudagrass had the greatest level of crude protein (CP), followed by panicgrass and bluestem. Fiber was greater in the first leaves than in the third leaves for bermudagrass and panicgrass but not for bluestem. Photosynthetic rates of panicgrass and bluestem third leaves estimated 2 wk after defoliation of the surrounding canopy were less than estimates made before defoliation in the first leaves but were similar to the third leaves before canopy defoliation. The third leaves of bermudagrass 2 wk after defoliation had lesser photosynthetic rates per unit chlorophyll than the first or third leaves before defoliation. Photosynthetic rates were correlated with hemicellulose across leaf classes and species (r2 = 0.93). The photosynthetic decline observed in third leaves of bermudagrass compared with panicgrass and bluestem is evidence of variation in leaf response after defoliation among warm‐season grasses.
Impact of Tillage and Banded Starter Fertilizer on Maize Root Growth in the Top 25 Centimeters of the Soil
Authors: Qin Ruijun , Stamp Peter , Richner Walter
Published: May 2005

There is little information about root growth response to tillage and starter fertilization in cool temperate regions. Maize (Zea mays L.) root morphology and distribution at anthesis were studied in 1997 and 1999 at two sites in the Swiss Midlands on a loamy silt and a sandy loam soil. The effects of tillage system, conventional tillage (CT) vs. no‐tillage (NT), and starter fertilizer (SF) banded to one side of the seed row were evaluated. Roots were determined in soil cores taken 9.5 cm on each side of the seed row and 25 cm deep. The overall root length density (RLD) was significantly greater under CT than under NT on the loamy silt soil but not on the sandy loam soil. In NT, RLD tended to be greater than in CT in the uppermost 5 to 10 cm of the soil but less in deeper soil. Mean root diameter (MD) under CT was smaller than under NT for both years and sites. In 1997, banded SF (BSF) improved RLD in the SF bands compared with the opposite side of the seed row; in 1999, this effect happened only in the uppermost soil layers (0 to 5 cm) in NT. Banded SF tended to increase MD in three combinations of year and site and to decrease it in Schafisheim 1999. Overall, this research indicates that the effects of tillage and BSF on root growth of maize at flowering were in accordance with the previous findings on early root growth. However, root growth response to tillage and SF is complex and often a function of year, soil type, and depth.
Temporal Origin of Nitrogen in the Grain of Tropical Wet‐Season Rice
Authors: Sheehy J. E. , Mnzava M. , Cassman K. G. , Mitchell P. L. , Ferrer A. B. , Robles R. P. , Pablico P.
Published: May 2005

The total N in the grain is the integral of the product of the total N absorbed at any instant and the fraction of that N eventually allocated to the grain. We investigated the temporal origin of N in the grain of a wet season rice crop and tested the suitability of 15N nitrate (NH4
15NO3) as a label for that purpose. The total N content of rice (Oryza sativa L.) plants was measured by growth analysis throughout the duration of the crop and the measurements were used to calculate the rate of total N uptake. A point‐placement technique was used to deliver small amounts of 15N nitrate to roots of the rice plant and this enabled the eventual fate of the total N absorbed at any time to be determined. The rate at which N was acquired by the panicle exceeded that by the whole plant at 64 d after transplanting (DAT); thereafter, N was transferred from the leaves to the panicle. About 60% of N in the grain was acquired before panicle initiation and was transferred from leaves during grain filling. A comparison between the uptake and retention of labeled nitrate and urea applied separately at 35 DAT showed that 21 and 58% of the 15N nitrate and 15N urea, respectively, were recovered. There were no advantages of using 15N nitrate as opposed to 15N urea as a label in such research of irrigated rice.
Seeding Practices and Cultivar Maturity Effects on Simulated Dryland Grain Sorghum Yield
Authors: Baumhardt R. L. , Tolk J. A. , Winter S. R.
Published: May 2005

Typical planting recommendations for dryland grain sorghum [Sorghum bicolor (L.) Moench] in the southern High Plains are to delay until soil water is adequate for crop establishment, but no population or cultivar maturity class are specified. Our objectives were to use the SORKAM simulation model, long‐term (1958–1998) weather records at Bushland, TX, and known Pullman soil (fine, mixed, superactive, thermic Torrertic Paleustolls) properties to identify an optimum planting date, population, row spacing, and cultivar maturity combination to maximize dryland grain sorghum yield. We simulated sorghum grain yields for combinations of planting dates (15 May, 5 June, and 25 June), populations (3, 6, and 12 plants m−2), row spacings (0.38 and 0.76 m), and cultivar maturity class (early, medium, and late). SORKAM consistently (r
2 = 0.69, RMSE = 792 kg ha−1) simulated grain yields that averaged about 5% more than measured values and correctly simulated row width and population effects on yield. Simulated grain yields increased with narrow row‐spacing ∼9%, independent of planting date or cultivar. Increasing plant population significantly decreased panicle seed number, seed mass, and plant tillers; however, the simulated grain yield was unchanged (3996–4106 kg ha−1) by plant populations. Mean simulated grain yields were greatest for the 5 June planting dates with early and medium maturity cultivars that avoided late summer heat or water deficit stresses and matured before freezing weather. Our results show early or medium maturity cultivars, planted 5 June, in 0.38‐m row widths, using 3 or 6 plants m−2, achieve the greatest dryland grain yield on a southern High Plains clay loam soil.