bluuebunny/crossref_metadata_2025_split huggingface dataset:
Value of Social Capital to Mid‐Sized Northern Plains Farms
Authors: Gustafson Cole R. , Nganje William E. 
Published: August 2006

As farms increase in size, operators face the decision of remaining loyal to local retail merchants or obtaining volume discounts from distant wholesale input suppliers. When farmers bypass local merchants and buy inputs in volume, they often realize price discounts but forego many services including credit forbearance. When farmers buy locally, they pay higher prices, which decreases profits and increases financial risk, but generates social capital which can be drawn upon during periods of economic adversity. A theoretical model of farm financial risk evaluates borrower behavior in light of cash flow constraints, volume discounts, and social capital. Results delineate financial risks involved and value of social capital. When inputs are purchased locally and social capital is generated, the distribution of year‐end funds had a slightly lower mean and longer left tail. The longer left tail results from additional borrowing arising from credit forbearance. If this forbearance were not available, the firm would be bankrupt. À mesure que la taille des exploitations agricoles augmente, les producteurs doivent décider s'ils demeurent loyaux envers les détaillants locaux ou s'ils tentent d'obtenir des remises sur quantité auprès de fournisseurs d'intrants éloignés. Lorsque les producteurs contournent les marchands locaux et achètent des intrants en grande quantité, ils obtiennent souvent des rabais sur le prix, mais se privent de nombreux services y compris l'indulgence des créanciers. Lorsque les producteurs achètent localement, ils paient des prix plus élevés, ce qui diminue les profits et augmente le risque financier, mais crée du capital social qui peut être mis à contribution en périodes d'adversitééconomique. Un modèle théorique de risque financier agricole évalue le comportement de l'emprunteur en tenant compte des contraintes de liquidités, des remises sur quantité et du capital social. Les résultats présentent en détail les risques financiers en jeu et la valeur du capital social. Lorsque les intrants sont achetés localement et qu'il y a création de capital social, la queue gauche de la distribution des fonds de fin d'année est plus longue et la moyenne est légèrement plus faible. Cette queue gauche plus longue découle des emprunts supplémentaires résultant de l'indulgence des créanciers. Sans cette indulgence, l'entreprise serait en faillite.
A Mutation in the
luxS
Gene Influences
Listeria monocytogenes
Biofilm Formation
Authors: Sela Shlomo , Frank Shmulik , Belausov Eddy , Pinto Riky 
Published: August 2006

ABSTRACT

Using a
Vibrio harveyi
reporter strain, we demonstrated that
Listeria monocytogenes
secretes a functional autoinducer 2 (AI-2)-like signal. A
luxS
-deficient mutant produced a denser biofilm and attached to a glass surface 19-fold better than the parent strain. Exogenous AI-2 failed to restore the wild-type phenotype to the mutant. It seems that an intact
luxS
gene is associated with repression of components required for attachment and biofilm formation.
Intraspecific Genotypic Characterization of
Lactobacillus rhamnosus
Strains Intended for Probiotic Use and Isolates of Human Origin
Authors: Vancanneyt M. , Huys G. , Lefebvre K. , Vankerckhoven V. , Goossens H. , Swings J. 
Published: August 2006

ABSTRACT

A set of 118 strains of the species
Lactobacillus rhamnosus
was collected, including probiotic strains, research strains with potential probiotic properties, food starter cultures, and human isolates. The majority of the strains were collected from companies, hospitals, or culture collections or were obtained after contacting authors who reported clinical case studies in the literature. The present work aimed to reveal the genotypic relationships between strains of these diverse sources. All strains were initially investigated using fluorescent amplified fragment length polymorphism (FAFLP) with three different primer combinations. Numerical analysis of FAFLP data allowed (i) confirmation of the identification of all strains as members of
L. rhamnosus
and (ii) delineation of seven stable intraspecific FAFLP clusters. Most of these clusters contained both (potentially) probiotic strains and isolates of human origin. For each of the clusters, strains of different sources were selected for pulsed-field gel electrophoresis (PFGE) of macrorestriction fragments obtained with the enzymes NotI and AscI. Analysis of PFGE data indicated that (i) some (potentially) probiotic strains were indistinguishable from other probiotic strains, suggesting that several companies may use duplicate cultures of the same probiotic strain, and (ii) in a number of cases human isolates from sterile body sites were indistinguishable from a particular probiotic strain, suggesting that some of these isolates may be reisolations of commercial strains.
Impact of Protists on the Activity and Structure of the Bacterial Community in a Rice Field Soil
Authors: Murase Jun , Noll Matthias , Frenzel Peter 
Published: August 2006

ABSTRACTFlooded rice fields have become a model system for the study of soil microbial ecology. In Italian rice fields, in particular, aspects from biogeochemistry to molecular ecology have been studied, but the impact of protistan grazing on the structure and function of the prokaryotic community has not been examined yet. We compared an untreated control soil with a γ-radiation-sterilized soil that had been reinoculated with a natural bacterial assemblage. In order to verify that the observed effects were due to protistan grazing and did not result from sterilization, we set up a third set of microcosms containing sterilized soil that had been reinoculated with natural assemblage bacteria plus protists. The spatial and temporal changes in the protistan and prokaryotic communities were examined by denaturing gradient gel electrophoresis (DGGE) and terminal restriction fragment length polymorphism (T-RFLP) analysis, respectively, both based on the small-subunit gene. Sequences retrieved from DGGE bands were preferentially affiliated with Cercozoa and other bacteriovorous flagellates. Without protists, the level of total DNA increased with incubation time, indicating that the level of the microbial biomass was elevated.Betaproteobacteriawere preferentially preyed upon, while low-G+C-content gram-positive bacteria became more dominant under grazing pressure. The bacterial diversity detectable by T-RFLP analysis was greater in the presence of protists. The level of extractable NH4+was lower and the level of extractable SO42−was higher without protists, indicating that nitrogen mineralization and SO42−reduction were stimulated by protists. Most of these effects were more obvious in the partially oxic surface layer (0 to 3 mm), but they could also be detected in the anoxic subsurface layer (10 to 13 mm). Our observations fit well into the overall framework developed for protistan grazing, but with some modifications pertinent to the wetland situation: O2was a major control, and O2availability may have limited directly and indirectly the development of protists. Although detectable in the lower anoxic layer, grazing effects were much more obvious in the partially oxic surface layer.
Analyses of Cry1Ab Binding in Resistant and Susceptible Strains of the European Corn Borer,
Ostrinia nubilalis
(Hübner) (Lepidoptera: Crambidae)
Authors: Siqueira Herbert A. A. , González-Cabrera Joel , Ferré Juan , Flannagan Ronald , Siegfried Blair D. 
Published: August 2006

ABSTRACT

Cry1Ab toxin binding analysis was performed to determine whether resistance in laboratory-selected
Ostrinia nubilalis
strains is associated with target site alteration. Brush border membrane vesicles were prepared using dissected midguts from late instars of susceptible and resistant strains (Europe-R and RSTT) of
O. nubilalis
. Immunoblot analysis indicated that three different proteins bound to Cry1Ab toxin and were recognized by an anticadherin serum. In a comparison of resistant and susceptible strains, reduced Cry1Ab binding was apparent for all three bands corresponding to cadherin-like proteins in the Europe-R strain, while reduced binding was apparent in only one band for the RSTT strain. Real-time analysis of Cry1Ab binding to gut receptors using surface plasmon resonance suggested slight differences in affinity in both resistant strains. Additional binding analysis was conducted using
125
I-labeled Cry1Ab, Cry1Ac, and Cry1Aa. Slight differences were again observed between the resistant and susceptible strains for Cry1Ab binding. However, when binding of
125
I-labeled Cry1Aa was tested, a 10-fold reduction in the concentration of binding sites was observed in the Europe-R strain. Expression of the
O. nubilalis
cadherin gene was similar in both the resistant and susceptible strains and did not account for differences in binding. In combination, the results of the present work suggest that differences in susceptibility to Cry1A toxins in the Europe-R strain of
O. nubilalis
are associated with altered receptor binding, although the precise nature of this mechanism is still uncertain.
Metal Accumulation without Enhanced Oxalate Secretion in Wood Degraded by Brown Rot Fungi
Authors: Schilling Jonathan S. , Jellison Jody 
Published: August 2006

ABSTRACT
Brown rot fungi were incubated in agar and agar-wood microcosms containing metallic or hydroxide forms of Al, Cu, and Fe. Metal dissolution was associated with elevated oxalate concentrations in agar, but metals translocated into wood did not affect oxalate accumulation, crystal production, or decay rate, demonstrating a substrate-dependent oxalate dynamic.
Temporal Transcriptomic Analysis as
Desulfovibrio vulgaris
Hildenborough Transitions into Stationary Phase during Electron Donor Depletion
Authors: Clark M. E. , He Q. , He Z. , Huang K. H. , Alm E. J. , Wan X.-F. , Hazen T. C. , Arkin A. P. , Wall J. D. , Zhou J.-Z. , Fields M. W. 
Published: August 2006

ABSTRACT

Desulfovibrio vulgaris
was cultivated in a defined medium, and biomass was sampled for approximately 70 h to characterize the shifts in gene expression as cells transitioned from the exponential to the stationary phase during electron donor depletion. In addition to temporal transcriptomics, total protein, carbohydrate, lactate, acetate, and sulfate levels were measured. The microarray data were examined for statistically significant expression changes, hierarchical cluster analysis, and promoter element prediction and were validated by quantitative PCR. As the cells transitioned from the exponential phase to the stationary phase, a majority of the down-expressed genes were involved in translation and transcription, and this trend continued at the remaining times. There were general increases in relative expression for intracellular trafficking and secretion, ion transport, and coenzyme metabolism as the cells entered the stationary phase. As expected, the DNA replication machinery was down-expressed, and the expression of genes involved in DNA repair increased during the stationary phase. Genes involved in amino acid acquisition, carbohydrate metabolism, energy production, and cell envelope biogenesis did not exhibit uniform transcriptional responses. Interestingly, most phage-related genes were up-expressed at the onset of the stationary phase. This result suggested that nutrient depletion may affect community dynamics and DNA transfer mechanisms of sulfate-reducing bacteria via the phage cycle. The putative
feoAB
system (in addition to other presumptive iron metabolism genes) was significantly up-expressed, and this suggested the possible importance of Fe
2+
acquisition under metal-reducing conditions. The expression of a large subset of carbohydrate-related genes was altered, and the total cellular carbohydrate levels declined during the growth phase transition. Interestingly, the
D. vulgaris
genome does not contain a putative
rpoS
gene, a common attribute of the δ-
Proteobacteria
genomes sequenced to date, and the transcription profiles of other putative
rpo
genes were not significantly altered. Our results indicated that in addition to expected changes (e.g., energy conversion, protein turnover, translation, transcription, and DNA replication and repair), genes related to phage, stress response, carbohydrate flux, the outer envelope, and iron homeostasis played important roles as
D. vulgaris
cells experienced electron donor depletion.
Identification of Bacterial Micropredators Distinctively Active in a Soil Microbial Food Web
Authors: Lueders Tillmann , Kindler Reimo , Miltner Anja , Friedrich Michael W. , Kaestner Matthias 
Published: August 2006

ABSTRACT

The understanding of microbial interactions and trophic networks is a prerequisite for the elucidation of the turnover and transformation of organic materials in soils. To elucidate the incorporation of biomass carbon into a soil microbial food web, we added
13
C-labeled
Escherichia coli
biomass to an agricultural soil and identified those indigenous microbes that were specifically active in its mineralization and carbon sequestration. rRNA stable isotope probing (SIP) revealed that uncultivated relatives of distinct groups of gliding bacterial micropredators (
Lysobacter
spp.,
Myxococcales
, and the
Bacteroidetes
) lead carbon sequestration and mineralization from the added biomass. In addition, fungal populations within the
Microascaceae
were shown to respond to the added biomass after only 1 h of incubation and were thus surprisingly reactive to degradable labile carbon. This RNA-SIP study identifies indigenous microbes specifically active in the transformation of a nondefined complex carbon source, bacterial biomass, directly in a soil ecosystem.
Evidence for Geographic Isolation and Signs of Endemism within a Protistan Morphospecies
Authors: Boenigk Jens , Pfandl Karin , Garstecki Tobias , Harms Hauke , Novarino Gianfranco , Chatzinotas Antonis 
Published: August 2006

ABSTRACT

The possible existence of endemism among microorganisms resulting from and preserved by geographic isolation is one of the most controversial topics in microbial ecology. We isolated 31 strains of “
Spumella
-like” flagellates from remote sampling sites from all continents, including Antarctica. These and another 23 isolates from a former study were characterized morphologically and by small-subunit rRNA gene sequence analysis and tested for the maximum temperature tolerance. Only a minority of the
Spumella
morpho- and phylotypes from the geographically isolated Antarctic continent follow the worldwide trend of a linear correlation between ambient (air) temperature during strain isolation and heat tolerance of the isolates. A high percentage of the Antarctic isolates, but none of the isolates from locations on all other continents, were obligate psychrophilic, although some of the latter were isolated at low ambient temperatures. The drastic deviation of Antarctic representatives of
Spumella
from the global trend of temperature adaptation of this morphospecies provides strong evidence for geographic transport restriction of a microorganism; i.e., Antarctic protistan communities are less influenced by transport of protists to and from the Antarctic continent than by local adaptation, a subtle form of endemism.
Production of Resveratrol in Recombinant Microorganisms
Authors: Beekwilder Jules , Wolswinkel Rianne , Jonker Harry , Hall Robert , de Vos C. H. Ric , Bovy Arnaud 
Published: August 2006

ABSTRACT

Resveratrol production in
Saccharomyces cerevisiae
was compared to that in
Escherichia coli
. In both systems, 4-coumarate:coenzyme A ligase from tobacco and stilbene synthase from grapes were expressed. When
p
-coumaric acid was used as the precursor, resveratrol accumulations in the culture medium were observed to be comparable in
E. coli
(16 mg/liter) and yeast (6 mg/liter).
Survival ofLactobacillus caseiin the Human Digestive Tract after Consumption of Fermented Milk
Authors: Oozeer Raish , Leplingard Antony , Mater Denis D. G. , Mogenet Agnès , Michelin Rachel , Seksek Isabelle , Marteau Philippe , Doré Joël , Bresson Jean-Louis , Corthier Gérard 
Published: August 2006

ABSTRACTA human trial was carried out to assess the ileal and fecal survival ofLactobacillus caseiDN-114 001 ingested in fermented milk. Survival rates were up to 51.2% in the ileum and 28.4% in the feces. The probiotic bacterium has the capacity to survive during its transit through the human gut.
Real-Time Detection of Noroviruses in Surface Water by Use of a Broadly Reactive Nucleic Acid Sequence-Based Amplification Assay
Authors: Rutjes Saskia A. , van den Berg Harold H. J. L. , Lodder Willemijn J. , de Roda Husman Ana Maria 
Published: August 2006

ABSTRACT
Noroviruses are the most common agents causing outbreaks of viral gastroenteritis. Outbreaks originating from contaminated drinking water and from recreational waters have been described. Due to a lack of cell culture systems, noroviruses are detected mostly by molecular methods. Molecular detection assays for viruses in water are often repressed by inhibitory factors present in the environment, like humic acids and heavy metals. To study the effect of environmental inhibitors on the performance of nucleic acid sequence-based amplification (NASBA), we developed a real-time norovirus NASBA targeting part of the RNA-dependent RNA polymerase (RdRp) gene. Specificity of the assay was studied with 33 divergent clones that contained part of the targeted RdRp gene of noroviruses from 15 different genogroups. Viral RNA originated from commercial oysters, surface waters, and sewage treatment plants in The Netherlands. Ninety-seven percent of the clones derived from human noroviruses were detected by real-time NASBA. Two clones containing animal noroviruses were not detected by NASBA. We compared the norovirus detection by real-time NASBA with that by conventional reverse transcriptase PCR (RT-PCR) with large-volume river water samples and found that inhibitory factors of RT-PCR had little or no effect on the performance of the norovirus NASBA. This consequently resulted in a higher sensitivity of the NASBA assay than of the RT-PCR. We show that by combining an efficient RNA extraction method with real-time NASBA the sensitivity of norovirus detection in water samples increased at least 100 times, which consequently has implications for the outcome of the infectious risk assessment.
Phylogeny of 16S rRNA, Ribulose 1,5-Bisphosphate Carboxylase/Oxygenase, and Adenosine 5′-Phosphosulfate Reductase Genes from Gamma- and Alphaproteobacterial Symbionts in Gutless Marine Worms (Oligochaeta) from Bermuda and the Bahamas
Authors: Blazejak Anna , Kuever Jan , Erséus Christer , Amann Rudolf , Dubilier Nicole 
Published: August 2006

ABSTRACTGutless oligochaetes are small marine worms that live in obligate associations with bacterial endosymbionts. While symbionts from several host species belonging to the genusOlaviushave been described, little is known of the symbionts from the host genusInanidrilus. In this study, the diversity of bacterial endosymbionts inInanidrilus leukodermatusfrom Bermuda andInanidrilus makropetalosfrom the Bahamas was investigated using comparative sequence analysis of the 16S rRNA gene and fluorescence in situ hybridization. As in all other gutless oligochaetes examined to date,I. leukodermatusandI. makropetalosharbor large, oval bacteria identified as Gamma 1 symbionts. The presence of genes coding for ribulose-1,5-bisphosphate carboxylase/oxygenase form I (cbbL) and adenosine 5′-phosphosulfate reductase (aprA) supports earlier studies indicating that these symbionts are chemoautotrophic sulfur oxidizers. Alphaproteobacteria, previously identified only in the gutless oligochaeteOlavius loisaefrom the southwest Pacific Ocean, coexist with the Gamma 1 symbionts in bothI. leukodermatusandI. makropetalos, with the former harboring four and the latter two alphaproteobacterial phylotypes. The presence of these symbionts in hosts from such geographically distant oceans as the Atlantic and Pacific suggests that symbioses with alphaproteobacterial symbionts may be widespread in gutless oligochaetes. The high phylogenetic diversity of bacterial endosymbionts in two species of the genusInanidrilus, previously known only from members of the genusOlavius, shows that the stable coexistence of multiple symbionts is a common feature in gutless oligochaetes.
Parametric general variational-like inequality problem in uniformly smooth Banach space
Authors: Kazmi KR , Khan FA 
Published: August 2006

AbstractUsing the concept of "Equation missing"- "Equation missing"-proximal mapping, we study the existence and sensitivity analysis of solution of a parametric general variational-like inequality problem in uniformly smooth Banach space. The approach used may be treated as an extension and unification of approaches for studying sensitivity analysis for various important classes of variational inequalities given by many authors in this direction.
Approximation common fixed point of asymptotically quasi-nonexpansive-type mappings by the finite steps iterative sequences
Authors: Quan Jing , Chang Shih-Sen , Long Xian Jun 
Published: August 2006

AbstractThe purpose of this paper is to study sufficient and necessary conditions for finite-step iterative sequences with mean errors for a finite family of asymptotically quasi-nonexpansive and type mappings in Banach spaces to converge to a common fixed point. The results presented in this paper improve and extend the recent ones announced by Ghost-Debnath, Liu, Xu and Noor, Chang, Shahzad et al., Shahzad and Udomene, Chidume et al., and all the others.
The Aurora Kinase Inhibitor VX-680 Induces Endoreduplication and Apoptosis Preferentially in Cells with Compromised p53-Dependent Postmitotic Checkpoint Function
Authors: Gizatullin Farid , Yao Yao , Kung Victor , Harding Matthew W. , Loda Massimo , Shapiro Geoffrey I. 
Published: August 2006

AbstractVX-680 is a potent inhibitor of Aurora kinases that induces the accumulation of cells with ≥4N DNA content, followed by cell death. Here, we define the role of p53 and p21Waf1/Cip1 in cell cycle perturbations following exposure to VX-680. Endoreduplication and apoptosis in response to VX-680 are limited in A549 and MCF-7 cells expressing wild-type p53, and markedly enhanced in cells lacking p53, including those engineered to express the HPV16-E6 oncoprotein or short interfering RNA pools targeting p53. In contrast, endoreduplication and apoptosis occur in the p53 wild-type cell lines, RKO and U2OS. The difference in response to VX-680 among these cell lines correlates with the timing of induction of p21Waf1/Cip1 and its ability to inhibit cyclin E-cdk2 activity. In A549 cells, VX-680 induces the expression of p53 and p21Waf1/Cip1 within 24 hours, with consequent inhibition of cyclin E-cdk2, and reduction of retinoblastoma protein phosphorylation, limiting endoreduplication. In RKO and U2OS cells, the induction of p21Waf1/Cip1 is delayed and associated with higher residual cyclin E-cdk2 kinase activity and retinoblastoma protein phosphorylation, followed by progressive endoreduplication and apoptosis. Abrogation of p21Waf1/Cip1 expression by short interfering RNA targeting in A549 cells results in a substantial increase in the degree of endoreduplication, whereas inducible expression of p21Waf1/Cip1 in p53-negative NCI-H1299 cells inhibits VX-680-induced endoreduplication and cell death. These data suggest that the integrity of the p53-p21Waf1/Cip1–dependent postmitotic checkpoint governs the response to Aurora kinase inhibition. Although cells with intact checkpoint function arrest with 4N DNA content, those with compromised checkpoint function are more likely to undergo endoreduplication followed by eventual apoptosis. (Cancer Res 2006; 66(15): 7668-77)