bluuebunny/crossref_metadata_2025_split huggingface dataset:
Beringia as a glacial refugium for boreal trees and shrubs: new perspectives from mapped pollen data
Authors: Brubaker Linda B. , Anderson Patricia M. , Edwards Mary E. , Lozhkin Anatoly V. 
Published: April 2005

AbstractAim Beringia, far north‐eastern Siberia and north‐western North America, was largely unglaciated during the Pleistocene. Although this region has long been considered an ice‐age refugium for arctic herbs and shrubs, little is known about its role as a refugium for boreal trees and shrubs during the last glacial maximum (LGM,c. 28,000–15,000 calibrated years before present). We examine mapped patterns of pollen percentages to infer whether six boreal tree and shrub taxa (Populus,Larix,Picea,Pinus,Betula,Alnus/Duschekia) survived the harsh glacial conditions within Beringia.Methods Extensive networks of pollen records have the potential to reveal distinctive temporal–spatial patterns that discriminate between local‐ and long‐distance sources of pollen. We assembled pollen records for 149 lake, peat and alluvial sites from the Palaeoenvironmental Arctic Sciences database, plotting pollen percentages at 1000‐year time intervals from 21,000 to 6000 calibrated years before present. Pollen percentages are interpreted with an understanding of modern pollen representation and potential sources of long‐distance pollen during the glacial maximum. Inferences from pollen data are supplemented by published radiocarbon dates of identified macrofossils, where available.Results Pollen maps for individual taxa show unique temporal‐spatial patterns, but the data for each taxon argue more strongly for survival within Beringia than for immigration from outside regions. The first increase ofPopuluspollen percentages in the western Brooks Ranges is evidence thatPopulustrees survived the LGM in central Beringia. Both pollen and macrofossil evidence supportLarixsurvival in western Beringia (WB), but data forLarixin eastern Beringia (EB) are unclear. Given the similar distances of WB and EB to glacial‐age boreal forests in temperate latitudes of Asia and North America, the widespread presence ofPiceapollen in EB andPinuspollen in WB indicates thatPiceaandPinussurvived within these respective regions.Betulapollen is broadly distributed but highly variable in glacial‐maximum samples, suggesting thatBetulatrees or shrubs survived in restricted populations throughout Beringia.Alnus/Duschekiapercentages show complex patterns, but generally support a glacial refugium in WB.Main conclusions Our interpretations have several implications, including: (1) the rapid post‐glacial migration rate reported forPiceain western Canada may be over estimated, (2) the expansion of trees and shrubs within Beringia should have been nearly contemporaneous with climatic change, (3) boreal trees and shrubs are capable of surviving long periods in relatively small populations (at the lower limit of detection in pollen data) and (4) long‐distance migration may not have been the predominant mode of vegetation response to climatic change in Beringia.
Response of semi‐desert grasslands invaded by non‐native grasses to altered disturbance regimes
Authors: Geiger Erika L. , McPherson Guy R. 
Published: April 2005

AbstractAim  Using a long‐term data set we investigated the response of semi‐desert grasslands to altered disturbance regimes in conjunction with climate patterns. Specifically, we were interested in the response of a non‐native grass (Eragrostis lehmanniana), mesquite (Prosopis velutina), and native species to the reintroduction of fire and removal of livestock.Location  The study site is located on the 45,360‐ha Buenos Aires National Wildlife Refuge (31°32′ N, 110°30′ W) in southern Arizona, USA. In 1985, livestock were removed and prescribed fires were reintroduced to this semi‐desert grassland dominated by non‐native grasses and encroaching mesquite trees.Methods  Plant species cover was monitored along 38, 30‐m transects five times over a period of 15 years. Data were analysed using principal components analysis on the variance–covariance and correlation matrix, multivariate analysis of variance for changes over time in relation to environmental data, and analysis of variance for altered disturbance regimes.Results  Reintroduction of fire and removal of livestock have not led to an increase in native species diversity or a decrease in non‐native grasses or mesquite. The cover of non‐native grass was influenced by soil type in 1993.Main conclusions  Variability of plant community richness, diversity, and cover over time appear to be most closely linked to fluctuations in precipitation rather than human‐altered disturbance regimes. The effects of altered grazing and fire regimes are likely confounded by complex interactions with climatic factors in systems significantly altered from their original physiognomy.
Mutants in DEFECTIVE GLYCOSYLATION, an Arabidopsis homolog of an oligosaccharyltransferase complex subunit, show protein underglycosylation and defects in cell differentiation and growth
Authors: Lerouxel Olivier , Mouille Grégory , Andème‐Onzighi Christine , Bruyant Marie‐Pierre , Séveno Martial , Loutelier‐Bourhis Corinne , Driouich Azeddine , Höfte Herman , Lerouge Patrice 
Published: April 2005

SummaryA mutant called defective glycosylation1‐1 (dgl1‐1) was identified in Arabidopsis based on a growth defect of the dark‐grown hypocotyl and an abnormal composition of the non‐cellulosic cell wall polysaccharides. dgl1‐1 is altered in a protein ortholog of human OST48 or yeast WBP1, an essential protein subunit of the oligosaccharyltransferase (OST) complex, which is responsible for the transfer in the ER of the N‐linked glycan precursor onto Asn residues of candidate proteins. Consistent with the known function of the OST complex in eukaryotes, the dgl1‐1 mutation led to a reduced N‐linked glycosylation of the ER‐resident protein disulfide isomerase. A second more severe mutant (dgl1‐2) was embryo‐lethal. Microscopic analysis of dgl1‐1 revealed developmental defects including reduced cell elongation and the collapse and differentiation defects of cells in the central cylinder. These defects were accompanied by changes in the non‐cellulosic polysaccharide composition, including the accumulation of ectopic callose. Interestingly, in contrast to other dwarf mutants that are altered in early steps of the N‐glycan processing, dgl1‐1 did not exhibit a cellulose deficiency. Together, these results confirm the role of DGL1 in N‐linked glycosylation, cell growth and differentiation in plants.
Visualization of autophagy in Arabidopsis using the fluorescent dye monodansylcadaverine and a GFP‐AtATG8e fusion protein
Authors: Contento Anthony L. , Xiong Yan , Bassham Diane C. 
Published: April 2005

SummaryAutophagy is a process that is thought to occur in all eukaryotes in which cells recycle cytoplasmic contents when subjected to environmental stress conditions or during certain stages of development. Upon induction of autophagy, double membrane‐bound structures called autophagosomes engulf portions of the cytoplasm and transfer them to the vacuole or lysosome for degradation. In this study, we have characterized two potential markers for autophagy in plants, the fluorescent dye monodansylcadaverine (MDC) and a green fluorescent protein (GFP)‐AtATG8e fusion protein, and propose that they both label autophagosomes in Arabidopsis. Both markers label the same small, apparently membrane‐bound structures found in cells under conditions that are known to induce autophagy such as starvation and senescence. They are usually seen in the cytoplasm, but occasionally can be observed within the vacuole, consistent with a function in the transfer of cytoplasmic material into the vacuole for degradation. MDC‐staining and the GFP‐AtATG8e fusion protein can now be used as very effective tools to complement biochemical and genetic approaches to the study of autophagy in plant systems.
Arabidopsis mutants deregulated in RCI2A expression reveal new signaling pathways in abiotic stress responses
Authors: Medina Joaquín , Rodríguez‐Franco Marta , Peñalosa Andrés , Carrascosa María J. , Neuhaus Gunther , Salinas Julio 
Published: April 2005

SummaryTo uncover new pathways involved in low‐temperature signal transduction, we screened for mutants altered in cold‐induced expression of RCI2A, an Arabidopsis gene that is not a member of the CBF/DREB1 regulon and is induced not only by low temperature but also by abscisic acid (ABA), dehydration (DH) and NaCl. This was accomplished by generating a line of Arabidopsis carrying a transgene consisting of the RCI2A promoter fused to the firefly luciferase coding sequence. A number of mutants showing low or high RCI2A expression in response to low temperature were identified. These mutants also displayed deregulated RCI2A expression in response to ABA, DH or NaCl. Interestingly, however, they were not altered in stress‐induced expression of RD29A, a CBF/DREB1‐target gene, suggesting that the mutations affect signaling intermediates of CBF/DREB1‐independent regulatory pathways. Several mutants showed alterations in their tolerance to freezing, DH or salt stress, as well as in their ABA sensitivity, which indicates that the signaling intermediates defined by the corresponding mutations play an important role in Arabidopsis tolerance to abiotic stresses. Based on the mutants identified, we discuss the involvement of CBF/DREB1‐independent pathways in modulating stress signaling.
Safer injections, fewer infections: injection safety in rural north India
Authors: Kermode Michelle , Holmes Wendy , Langkham Biangtang , Thomas Mathew S. , Gifford Sandy 
Published: April 2005

SummaryBackground  Unsafe injection practices result in a substantial burden of preventable blood‐borne viral disease (BBV). The reasons are complex and include structural, economic and socio‐cultural factors.Objective  To describe injection‐related practices in two rural north Indian health settings including the contextual factor, highlight some of the challenges facing those endeavouring to translate injection safety policies into safe injection practice, and to identify appropriate intervention strategies.Method  Qualitative data collection (participant observation and in‐depth interviews) in two rural north Indian hospitals with affiliated community‐based programmes over a 4‐month period. A total of 130 h of observation took place in a range of clinical areas characterized by frequent use of needles and other sharps, and 40 healthcare workers were interviewed. Field notes and interview transcripts were thematically analysed.Results  Managers in these health settings were clearly endeavouring to promote injection safety by implementing the widespread use of disposable needles and syringes and attempting to address the difficult issue of safe healthcare waste management. However, some unsafe practices were still occurring: reuse of syringes (with and without sterilization) was relatively common, and use of multi‐dose vials, blood sampling, sterilization and disinfection, and healthcare waste management were sub‐optimal in some instances, placing both staff and patients at unnecessary risk of BBV infection.Conclusion  Strategies for promoting injection safety are necessary if the risk of nosocomial transmission of BBV diseases via unsafe injection practices in rural north India is to be minimized.
Exploring the decision‐making preferences of people with colorectal cancer
Authors: Beaver Kinta , Jones David , Susnerwala Shabbir , Craven Olive , Tomlinson Mary , Witham Gary , Luker Karen A 
Published: April 2005

AbstractObjectives  To explore patient views on participation in treatment, physical care and psychological care decisions and factors that facilitate and hinder patients from making decisions.Design  Qualitative study using semi‐structured interviews with patients.Setting and participants  Three NHS Trusts in the north‐west of England. Theoretical sampling including 41 patients who had been treated for colorectal cancer.Results  For patients, participation in the decision‐making process was about being informed and feeling involved in the consultation process, whether patients actually made decisions or not. The perceived availability of treatment choices (surgery, radiotherapy, chemotherapy) was related to type of treatment. Factors that impacted on whether patients wanted to make decisions included a lack of information, a lack of medical knowledge and trust in medical expertise. Patients perceived that they could have a more participatory role in decisions related to physical and psychological care.Conclusion  This study has implications for health professionals aiming to implement policy guidelines that promote patient participation and shared partnerships. Patients in this study wanted to be well informed and involved in the consultation process but did not necessarily want to use the information they received to make decisions. The presentation of choices and preferences for participation may be context specific and it cannot be assumed that patients who do not want to make decisions about one aspect of their care and treatment do not want to make decisions about other aspects of their care and treatment.
VISUAL IMPRINTS ON THE PRISON LANDSCAPE: A STUDY ON THE DECORATIONS IN PRISON CELLS
Authors: BAER LEONARD D. 
Published: April 2005

ABSTRACTWhile conducting my first research project on prisons, I noticed that some prisoners decorated their cells with massive quantities of bathing products and air freshener. I wondered why. This led to an impressionistic study that drew from visits to six young offender institutions and interviews with 11 prisoners in England. Prisoners and staff gave numerous explanations for such decorations, including: the commodification of everyday items, such as shower gels; social status; the creation of a home environment; the need to fill space; boredom; illegal activity; and the effect of sentence length on the personalisation of space. Michel de Certeau's idea of tactics is applied to the findings as mundane activities used by people in a position of weakness. Other visual imprints in the everyday surroundings of prisoners could also have numerous explanations. This study serves as a beginning for future research on the personalisation and meanings of prison spaces.
Binding and Internalization of C-Reactive Protein by Fcgamma Receptors on Human Aortic Endothelial Cells Mediates Biological Effects
Authors: Devaraj Sridevi , Du Clos Terry W. , Jialal Ishwarlal 
Published: April 2005

Objective—In addition to being a cardiovascular risk marker, recent studies support a role for CRP in atherothrombosis. Several investigators have reported that CRP binds to Fcgamma receptors on leukocytes. The aim of the study is to determine the processing of CRP by human aortic endothelial cells (HAECs).Methods and Results—Binding studies were performed by incubation of HAECs with biotinylated CRP (B-CRP, 25 to 200 μg/mL) for 30 to 180 minutes at 4°C. B-CRP binding was quantitated using streptavidin-fluorescein isothiocyanate followed by flow cytometry. Saturable binding of CRP was obtained at 60 minutes with a CRP concentration between 100 to 150 μg/mL and Kd of 88 nM. CRP binding was inhibited by 10× cold CRP (58%). CRP (100 μg/mL) significantly upregulated surface expression of Fcgamma receptors, CD32, as well as CD64 on HAECs (P<0.01). Also, preincubation with anti-CD32 and CD64 antibodies significantly inhibited maximal binding of CRP to HAECs 64% and 30%, respectively, whereas antibodies to CD16 had no effect. Internalization of CRP, as determined by loss of surface expression, was 50%. Also, binding and internalization of biotinylated CRP was confirmed by confocal microscopy and CRP colocalized with CD32 and CD64. Most importantly, the increase in interleukin-8, intercellular adhesion molecule 1, and vascular cell adhesion molecule-1 and the decrease in eNOS and prostacyclin induced by CRP was abrogated with antibodies to CD32 and CD64.Conclusions—We demonstrate that CRP mediates its biological effects on HAECs via binding and internalization through Fcgamma receptors, CD32 and CD64.
Rule-Based Category Learning is Impaired in Patients with Parkinson's Disease but not in Patients with Cerebellar Disorders
Authors: Maddox W. Todd , Aparicio Paul , Marchant Natalie L. , Ivry Richard B. 
Published: April 2005

Abstract
The basal ganglia and cerebellum have both been implicated in motor skill acquisition. Recent hypotheses concerning cognitive functions of the basal ganglia and cerebellum have emphasized that these subcortical structures may also contribute to nonmotor learning. To explore this issue, patients with Parkinson's disease (PD) and patients with cerebellar lesions (CB) were tested on two category-learning tasks. Identical stimulus displays were used for the two tasks, consisting of a reference line and target line. In the length task, the two categories were defined based on the length of the target line. In the distance task, the two categories were defined by the distance between the target and reference lines. Thus, both categories could be defined by a simple rule in which attention must be restricted to a single relevant dimension. Consistent with previous results, the patients with PD were impaired on both tasks compared with neurologically healthy controls. In contrast, the CB patients performed similar to the control participants. Model-based analyses indicate that the patients with PD were able to select the appropriate categorization rule, but that they adopted suboptimal category boundaries in both conditions and were more variable in the application of the selected rule. These results provide an important neuropsychological dissociation on a non-motor-learning task between the effects of basal ganglia and cerebellar lesions. Moreover, the modeling work suggests that at least part of the Parkinson patients' impairment on these tasks reflect a tendency to exhibit strong response biases.
An Electrophysiological Investigation of Factors Facilitating Strategic Recollection
Authors: Herron J. E. , Wilding E. L. 
Published: April 2005

Abstract
Episodic memory is thought to be mediated by executive processes that facilitate the retrieval of task-relevant information at the expense of irrelevant information. The exclusion task [A process dissociation framework: Separating automatic from intentional uses of memory.Journal of Memory and Language, 30, 513-541, 1991] can be used to explore these processes. In this task, studied items from one source (“targets”) are endorsed on one response key, whereas new and studied items from another source (“nontargets”) are rejected on another key. Herron and Rugg [Strategic influences on recollection in the exclusion task: Electrophysiological evidence.Psychonomic Bulletin and Review, 10, 703-710, 2003] reported that nontargets elicited the ERP correlate of recollection (the “left parietal old/new effect”) when target accuracy was low, but not when it was high. Their explanation for this was that participants only focused exclusively on the recollection of target information when the likelihood of target recollection was high, as under these conditions this strategy is one that that will give rise to accurate task performance. The fact, however, that targets were encoded in different tasks in the high-and low-accuracy groups means that the results can also be explained in terms of the encoding operations performed at study rather than in terms of target accuracy. This study was designed to distinguish between these competing accounts. All targets were encoded elaboratively. Target accuracy was reduced in one condition with a 40-min study-test interval. Nontargets elicited no left parietal effect in either condition, suggesting that target-specific strategic retrieval is facilitated by certain classes of encoding operations rather than simply high target accuracy per se.
Relating Eulerian and Lagrangian Statistics for the Turbulent Dispersion in the Atmospheric Convective Boundary Layer
Authors: Dosio Alessandro , Guerau de Arellano Jordi Vilá , Holtslag Albert A. M. , Builtjes Peter J. H. 
Published: April 2005

AbstractEulerian and Lagrangian statistics in the atmospheric convective boundary layer (CBL) are studied by means of large eddy simulation (LES). Spectra analysis is performed in both the Eulerian and Lagrangian frameworks, autocorrelations are calculated, and the integral length and time scales are derived. Eulerian statistics are calculated by means of spatial and temporal analysis in order to derive characteristic length and time scales. Taylor’s hypothesis of frozen turbulence is investigated, and it is found to be satisfied in the simulated flow.Lagrangian statistics are derived by tracking the trajectories of numerous particles released at different heights in the turbulent flow. The relationship between Lagrangian properties (autocorrelation functions) and dispersion characteristics (particles’ displacement) is studied through Taylor’s diffusion relationship, with special emphasis on the difference between horizontal and vertical motion. Results show that for the horizontal motion, Taylor’s relationship is satisfied. The vertical motion, however, is influenced by the inhomogeneity of the flow and limited by the ground and the capping inversion at the top of the CBL. The Lagrangian autocorrelation function, therefore, does not have an exponential shape, and consequently, the integral time scale is zero. If distinction is made between free and bounded motion, a better agreement between Taylor’s relationship and the particles’ vertical displacement is found.Relationships between Eulerian and Lagrangian frameworks are analyzed by calculating the ratio β between Lagrangian and Eulerian time scales. Results show that the integral time scales are mainly constant with height for z/zi &lt; 0.7. In the upper part of the CBL, the capping inversion transforms vertical motion into horizontal motion. As a result, the horizontal time scale increases with height, whereas the vertical one is reduced. Current parameterizations for the ratio between the Eulerian and Lagrangian time scales have been tested against the LES results showing satisfactory agreement at heights z/zi &lt; 0.7.