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Full-Text Articles in Life Sciences

Dissociation Of The Hepatic Phenotype From Hnf4 And Hnf1x Expression, Gary A. Bulla, David M. Kraus Dec 2004

Dissociation Of The Hepatic Phenotype From Hnf4 And Hnf1x Expression, Gary A. Bulla, David M. Kraus

Gary A. Bulla

Dedifferentiated cells have served as tools to understand the molecular consequences of the loss of tissue-specific pathways. Here we report the characterization of one of these cell lines, M29, which lacks the liver-enriched HNF4-HNF1x pathway, in order to determine if this class of variant cell lines could provide additional information regarding requirements for tissue-type expression. We report that although the liver-specific x1-antitrypsin (a1AT) gene remains silent despite reactivation of the HNF4/HNF1x pathway in the M29 cells, the frequency of activation of an integrated x1AT-APRT transgene is increased 1000-fold in response to these transcription factors. The human x1AT locus (introduced via …


Renesting Decisions And Annual Fecundity Of Female Dickcissels (Spiza Americana) In Illinois, Jeffrey W. Walk, Kevin Wentworth, Eric L. Kershner, Eric K. Bollinger, Richard E. Warner Oct 2004

Renesting Decisions And Annual Fecundity Of Female Dickcissels (Spiza Americana) In Illinois, Jeffrey W. Walk, Kevin Wentworth, Eric L. Kershner, Eric K. Bollinger, Richard E. Warner

Eric K. Bollinger

ABSTRACT.-Renesting decisions and annual fecundity are crucial for interpreting other demographic information, yet are infrequently reported. We used radiotelemetry to monitor female Dickcissels (Spiza americana) throughout the 1999 and 2000 breeding seasons in southeastern Illinois. Overall fecundity (regardless of whether females remained in the study area throughout the breeding season) was 0.61 ± 0.13 female fledglings per year. Of females that remained within the study area, 94% fledged young (1.25 ± 0.15 female fledglings per year). Most females (62%) that experienced nest failure emigrated from the study area (moved >10 km) in 2.8 ± 0.6 days; others (36%) initiated subsequent …


Responses Of Nesting Bobolinks (Dolichonyx Oryzivorus) To Habitat Edges, Eric K. Bollinger, Thomas A. Gavin Jul 2004

Responses Of Nesting Bobolinks (Dolichonyx Oryzivorus) To Habitat Edges, Eric K. Bollinger, Thomas A. Gavin

Eric K. Bollinger

T.-Avoidance of habitat edges may be contributing to reduced densities of grass- land birds in small habitat patches. Nest densities for grassland-nesting Bobolinks (Dolichonyx oryzivorus) were much lower than expected within 25 m of forest edges at three sites in New York, and that pattern ("edge avoidance") extended to 100 m at one site. Nests located within 50 m of forest or wooded hedgerow edges had lower daily survival rates, compared with nests >100 m from any habitat edge. Bobolinks tended to move away from forest edges when renest- ing after nest failure; that pattern was especially evident in females …


Physiology Of The Thermophilic Acetogen Moorella Thermoacetica, Harold L. Drake, Steven L. Daniel Apr 2004

Physiology Of The Thermophilic Acetogen Moorella Thermoacetica, Harold L. Drake, Steven L. Daniel

Steven L. Daniel

Moorella thermoacetica (originally isolated as Clostridium thermoaceticum) has served as the primary acetogenic bacterium for the resolution of the acetyl coenzyme A (acetyl-CoA) orWood–Ljungdahl pathway, a metabolic pathway that (i) autotrophically assimilates CO2 and (ii) is centrally important to the turnover of carbon in many habitats. The purpose of this article is to highlight the diverse physiological features of this model acetogen and to examine some of the consequences of its metabolic capabilities.


Oxalate Metabolism By The Acetogenic Bacterium Moorella Thermoacetica, Steven L. Daniel, Christine Pilsl, Harold L. Drake Feb 2004

Oxalate Metabolism By The Acetogenic Bacterium Moorella Thermoacetica, Steven L. Daniel, Christine Pilsl, Harold L. Drake

Steven L. Daniel

Whole-cell and cell-extract experiments were performed to study the mechanism of oxalate metabolism in the acetogenic bacterium Moorella thermoacetica. In short-term, whole-cell assays, oxalate consumption was low unless cell suspensions were supplemented with CO2, KNO3, or Na2S2O3. Cell extracts catalyzed the oxalate-dependent reduction of benzyl viologen. Oxalate consumption occurred concomitant to benzyl viologen reduction; when benzyl viologen was omitted, oxalate was not appreciably consumed. Based on benzyl viologen reduction, specific activities of extracts averaged 0.6 μmol oxalate oxidized min−1 mg protein−1. Extracts also catalyzed the formate-dependent reduction of NADP+; however, oxalate-dependent reduction of NADP+ was negligible. Oxalate- or formate-dependent reduction …


Noteworthy Collections: Florida, Barbara S. Carlsward, J Richard Abbott Jan 2004

Noteworthy Collections: Florida, Barbara S. Carlsward, J Richard Abbott

Barbara S. Carlsward

No abstract provided.


Systematic And Comparative Anatomy Of Maxillarieae (Orchidaceae), Sans Oncidiinae, William Louis Stern, Walter S. Judd, Barbara S. Carlsward Jan 2004

Systematic And Comparative Anatomy Of Maxillarieae (Orchidaceae), Sans Oncidiinae, William Louis Stern, Walter S. Judd, Barbara S. Carlsward

Barbara S. Carlsward

On the basis of floral and vegetative morphology, 63 tropical American genera have been recognized within Maxillarieae. We were able to examine anatomical material of all subtribes, excluding Oncidiinae. Stegmata with conical silica bodies occur in leaves and stems of all subtribes excluding Ornithocephalinae, and pericyclic stegmata found in roots are characteristic of Lycastinae. Lycastinae and Maxillariinae are characterized by foliar glands, foliar fibre bundles and tilosomes. Endodermal cells are U-thickened in most Zygopetalinae; O-thickened in most Lycastinae, Ornithocephalinae and Telipogoninae; variously thickened in Maxillariinae; and thin-walled in Cryptarrhena lunata. Water-storage cells varied from thin-walled to variously banded throughout Maxillarieae. …


Growth Rates, Survivorship, And Sex Ratios Of Juniperus Virginiana On The New Jersey Piedmont From 1963 To 2000, James A. Quinn, Scott J. Meiners Jan 2004

Growth Rates, Survivorship, And Sex Ratios Of Juniperus Virginiana On The New Jersey Piedmont From 1963 To 2000, James A. Quinn, Scott J. Meiners

Scott J. Meiners

Growth rates, survivorship, and sex ratios of Juniperus virginiana on the New Jersey Piedmont from 1963 to 2000. J. Torrey Bot. Soc. XXX:000–000. 20XX.—Studies of the growth, survival, and sex ratios of dioecious species have been predominantly short-term. This research investigated growth rates, survivorship, and sex ratios among cohorts of Juniperus virginiana L. from 1963 through 2000. Males (M) and females (F) in six old-fields of different ages on the New Jersey Piedmont were analyzed, starting with the initial data on height and sex expression collected by John Small on labeled recruits from 1963 through 1976. These plants were relocated …


Renesting Decisions And Annual Fecundity Of Female Dickcissels (Spiza Americana) In Illinois, Jeffery W. Walk, Kevin Wentworth, Eric L. Kershner, Eric K. Bollinger, Richard E. Warner Jan 2004

Renesting Decisions And Annual Fecundity Of Female Dickcissels (Spiza Americana) In Illinois, Jeffery W. Walk, Kevin Wentworth, Eric L. Kershner, Eric K. Bollinger, Richard E. Warner

Eric K. Bollinger

T.-Renesting decisions and annual fecundity are crucial for interpreting other demographic information, yet are infrequently reported. We used radiotelemetry to monitor female Dickcissels (Spiza americana) throughout the 1999 and 2000 breeding seasons in south- eastern Illinois. Overall fecundity (regardless of whether females remained in the study area throughout the breeding season) was 0.61 ? 0.13 female fledglings per year. Of females that re- mained within the study area, 94% fledged young (1.25 ? 0.15 female fledglings per year). Most females (62%) that experienced nest failure emigrated from the study area (moved >10 km) in 2.8 ? 0.6 days; others (36%) …


Demographics And The Ecological Role Of The Channel Catfish (Ictalurus Punctatus) In Commercially Exploited And Unexploited Reaches Of The Wabash River With Implications For The Flathead Catfish (Pylodictis Olivaris), Robert E. Colombo Jan 2004

Demographics And The Ecological Role Of The Channel Catfish (Ictalurus Punctatus) In Commercially Exploited And Unexploited Reaches Of The Wabash River With Implications For The Flathead Catfish (Pylodictis Olivaris), Robert E. Colombo

Robert E. Colombo

Catfish are a major component of the Wabash River fish assemblage and are commercially fished below river kilometer (Rkm) 500. From Rkm 322 through 499 the commercial fishery is subjected only to Indiana fishing regulations. In this reach of river, there is a 254-mm minimum total length limit on both sport and commercially harvested catfish. Below RM 322, the Wabash River forms the state boundary of Indiana and Illinois. In this region of river there are two different length limits on commercially harvested catfish with Indiana having a 254-mm length limit and Illinois having a 381-mm length limit. There is …