bluuebunny/crossref_metadata_2025 huggingface dataset:
Long‐term effects of mild salt stress on growth, ion accumulation and superoxide dismutase expression of Arabidopsis rosette leaves
Authors: Attia Houneida , Arnaud Nicolas , Karray Najoua , Lachaâl Mokhtar
Published: February 2008

Arabidopsis thaliana plants (wild‐type accessions Col and N1438) were submitted to a prolonged, mild salt stress using two types of protocols. These protocols allowed salt‐treated plants to absorb nutrients either through a part of their root system maintained in control medium (split‐rooted plants) or during episodes on control medium alternating with salt application (salt alternation experiment). Full‐salt treatments (salt applied continuously to whole root system) resulted in severe (but non‐lethal) growth inhibition. This effect was partly alleviated in split‐rooted plants on mixed salt–control medium and in plants submitted to salt–control medium alternation. The activity of the various isoforms of superoxide dismutases (SODs) did not appreciably change with the treatments. The abundance of the mRNAs of the seven SOD genes present in Arabidopsis genome was determined using real‐time polymerase chain reaction. The two protocols gave qualitatively identical results. The expression level was increased by full‐salt treatments for some genes and diminished for other genes. However, the nature of these genes differed according to the accessions: the responses to salt of FSD1 and MSD were opposite in Col and N1438. In Col, salt treatments inhibited the expression of FSD1 and strongly stimulated that of CSD1 and MSD. In N1438, the stimulation by salt concerned FSD1 and CSD1 and MSD expression being inhibited. In both accessions, the expression of CSD2 and CSD3 was lowered by salt. For all genes, the treatments that mitigated stress partially restored SOD expression to control level. Thus, the changes in SOD transcript abundance accurately reflected the severity of the salt stress.
Distribution, abundance, and growth of larval tautog, Tautoga onitis, in Buzzards Bay, Massachusetts, USA
Authors: Gauthier David A. , Lincoln Jean A. , Turner Jefferson T.
Published: February 2008

Tautog, Tautoga onitis, is an abundant species of fish in estuaries of the northeastern United States. Planktonic tautog larvae are abundant in summer in these estuaries, but there is little information on rates of growth of tautog larvae feeding on natural assemblages of food in the plankton. We examined abundance and growth of larval tautog and environmental factors during weekly sampling at three sites along a nearshore‐to‐offshore transect in Buzzards Bay, Massachusetts, USA during summer 1994. This is the first study of a robust sample size (336 larvae) to estimate growth rates of field‐caught planktonic tautog larvae feeding on natural diets, using the otolith daily‐growth‐increment method. The study was over the entire summer period when tautog larvae were in the plankton. The sampling sites contrasted in several environmental variables including temperature, dissolved oxygen (DO), and chlorophyll a concentration. There was a temporal progression in the abundance of tautog larvae over the summer, in relation to location and temperature. Tautog larvae were first present nearshore, with a pronounced peak in abundance occurring at the nearshore sites during the last 2 weeks in June. Larvae were absent at this time further offshore. From late June through August, larval abundance progressively decreased nearshore, but increased offshore although never approaching the abundance levels observed at the nearshore sites. The distribution and abundance of tautog larvae appeared to be related to a nearshore‐to‐offshore seasonal warming trend and a nearshore decrease in DO. Otoliths from 336 larvae ranging from 2.3 to 7.7 mm standard length had otolith increment counts ranging from 0 to 19 increments. Growth of larval tautog was estimated at 0.23 mm·day−1, and length of larvae prior to first increment formation was estimated at 2.8 mm indicating that first increment formation occurs 3–4 days after hatching at 2.2 mm. Despite spatial and temporal differences in environmental factors, there were no significant differences in growth rates at any of three given sites over time, or between sites. Because larval presence only occurred at a narrow range of temperature (17–23.5 °C) and DO (6.5–9.3 mg·l−1), in situ differences in growth did not appear to be because of differences in larval distribution and abundance patterns relative to these parameters.
The Determinants and Value Relevance of the Choice of Accounting for Research and Development Expenditures in the United Kingdom
Authors: Oswald Dennis R.
Published: February 2008

Abstract:  This paper investigates the determinants and value relevance implications of the accounting method choice for development expenditures for firms with research and development (R&D) programs in the United Kingdom (UK). Using a sample of 3,229 UK firm‐year observations over the period 1996–2004, I find that the decision to expense versus capitalize development expenditures is influenced by earnings variability, earnings sign, firm size, R&D intensity, leverage, steady‐state status of the firm's R&D program, and R&D program success. Additional results indicate that there is little difference in value relevance between reported and adjusted numbers for both the Expensers and the Capitalizers. The evidence in this paper suggests that managers choose the ‘correct’ method for accounting for R&D in order to best communicate the private information which they hold.
Large Shareholder Entrenchment and Performance: Empirical Evidence from Canada
Authors: Bozec Yves , Laurin Claude
Published: February 2008

Abstract:  Recent empirical evidence indicates that the largest publicly traded companies throughout the world have concentrated ownership. This is the case in Canada where voting rights are often concentrated in the hands of large shareholders, mostly wealthy families. Such concentrated ownership structures can generate specific agency problems, such as large shareholders expropriating wealth from minority shareholders. These costs are aggravated when large shareholders don't bear the full costs of their decisions because of the presence of mechanisms (dual class voting shares, pyramids) which lead to voting rights being greater than the cash flow rights (separation). We assess the impact of separation on various performance metrics while controlling for situations when the large shareholder has (1) the opportunity to expropriate (high free cash flows in the firm) and (2) the incentive to expropriate (low cash flow rights). We also control for when the large shareholder has the power to expropriate (high voting rights, outright control and insider management) and for the presence of family ownership. The results support our hypotheses and indicate that firm performance is lower when large shareholders have both the incentives and the opportunity to expropriate minority shareholders.
‘To make love to a Deformity’: praising ugliness in early modern England
Authors: Baker Naomi
Published: February 2008

This article discusses the fashion for witty celebrations of ugly women in early seventeenth‐century English literature. While apparently celebrating unconventional forms of beauty, texts ‘praising’ ugly women more accurately elevate masculine forms of artistic agency at the expense of the female body, which continues to be identified with ugly matter. Literary instances where ugliness is ‘celebrated’ work to contain the potentially threatening nature of the ugly female body. The article situates ‘deformed mistress’ texts in relation to wider early modern discourses of beauty and ugliness, discussing the extent to which categories of the artificial and the natural, in particular, are evaluated in gendered terms in this period.
Cortical auditory dysfunction in benign rolandic epilepsy
Authors: Boatman Dana F. , Trescher William H. , Smith Cynthia , Ewen Joshua , Los Jenna , Wied Heather M. , Gordon Barry , Kossoff Eric H. , Gao Qian , Vining Eileen P.
Published: February 2008

Summary

Purpose: To evaluate cortical auditory function, including speech recognition, in children with benign rolandic epilepsy (BRE).

Methods: Fourteen children, seven patients with BRE and seven matched controls, underwent audiometric and behavioral testing, simultaneous EEG recordings, and auditory‐evoked potential recordings with speech and tones. Speech recognition was tested under multiple listening conditions.

Results: All participants demonstrated normal speech recognition abilities in quiet, as well as normal peripheral and subcortical auditory function. BRE patients performed significantly worse than controls when speech recognition was tested under adverse listening conditions, including background noise. Five BRE patients who were impaired on two or more tests had centrotemporal spiking on awake EEG. There were no significant group differences in the latency or amplitude of early N100 cortical responses to speech or tones. Conversely, the mismatch negativity, a preattentive index of cortical processing that is elicited passively, was absent or prolonged for speech, but not tones, in BRE patients as compared to controls.

Discussion: Children with BRE demonstrated specific speech recognition impairments. Our evoked potential findings indicate that these behavioral impairments reflect dysfunction of nonprimary auditory cortex and cannot be attributed solely to attention difficulties. A possible association between auditory impairments and centrotemporal spiking (>1/min) on awake EEG was identified. The pattern of speech recognition impairments observed is a known risk factor for academic difficulties in school‐age children. Our results underscore the importance of comprehensive auditory testing, using behavioral and electrophysiological measures, in children with BRE.
When Can We Expect the Unexpected? Predicting Educational Attainment When it Differs from Previous Expectations
Authors: Messersmith Emily E. , Schulenberg John E.
Published: February 2008

Individuals' expectations are strong predictors of their behaviors; educational expectations predict enrollment in postsecondary education. Yet in many cases, a youth's previous educational expectations are not met or are exceeded. This study examines correlates of educational expectations and unexpected educational attainment using longitudinal data from Monitoring the Future, a U.S. national study. Demographic characteristics, educational experiences in high school, and other risk and protective factors were related to expectations for educational attainment during high school. Logistic regressions indicated that high school curriculum, average grades, educational aspirations, and parents' educational level were particularly strong indicators of youth not meeting their expectation to graduate from a 4‐year college, or graduating from college despite expecting not to graduate by age 25/26. We discuss the implications of unexpected pathways in terms of discontinuity during transitions and consider the implications for improved educational and career counseling during high school.
Voluntary Environmental Programs: A Canadian Perspective
Authors: Henriques Irene , Sadorsky Perry
Published: February 2008

In light of the increasing number of environmental problems necessitating government's attention and the limited scope and budget for addressing these issues, environmental protection has, and continues to evolve as more flexible approaches to regulation are being sought and embraced by governments throughout the world. Voluntary environmental programs (VEPs) are a pragmatic response by both governments and business to find a more flexible way to protect the environment. We discuss the theoretical motivations for firms to adopt VEPs in general and examine Canada's experience with three types of VEPs, public, negotiated, and unilateral agreements, to assess whether the motivating factors are present. We then argue that the institutional, political, and regulatory framework governing environmental policy in Canada does not provide the conditions necessary to effectively promote superior corporate environmental protection across jurisdictions. Despite the lack of government‐directed VEPs, there has been considerable interest by both the private sector and civil society who have taken the lead by developing unilateral agreements. Using existing literature and our current research, we examine the factors that motivate firms in Canada to participate in unilateral agreements and the characteristics of firms with the higher environmental performance and suggest some policy implications.
Intravital two‐photon microscopy: focus on speed and time resolved imaging modalities
Authors: Niesner Raluca A. , Andresen Volker , Gunzer Matthias
Published: February 2008

Summary: Initially used mainly in the neurosciences, two‐photon microscopy has become a powerful tool for the analysis of immunological processes. Here, we describe currently available two‐photon microscopy techniques with a focus on novel approaches that allow very high image acquisition rates compared with state‐of‐the‐art systems. This improvement is achieved through a parallelization of the excitation process: multiple beams scan the sample simultaneously, and the fluorescence is collected with sensitive charge‐coupled device (CCD)‐based line or field detectors. The new technique's performance is compared with conventional single beam laser‐scanning systems that detect signals by means of photomultipliers. We also discuss the use of time‐ and polarization‐resolved fluorescence detection, especially fluorescence lifetime imaging (FLIM), which goes beyond simple detection of cells and tissue structures and allows insight into cellular physiology. We focus on the analysis of endogenous fluorophores such as NAD(P)H as a way to analyze the redox status in cells with subcellular resolution. Here, high‐speed imaging setups in combination with novel ways of data analysis allow the generation of FLIM data sets almost in real time. The implications of this technology for the analysis of immune reactions and other cellular processes are discussed.
Signal initiation in T‐cell receptor microclusters
Authors: Seminario Maria‐Cristina , Bunnell Stephen C.
Published: February 2008

Summary: Although dynamic imaging technologies have provided important insights into the underlying processes responsible for T‐cell activation, the processes that link antigen recognition to downstream signaling remain poorly defined. Converging lines of inquiry indicate that T‐cell receptor (TCR) microclusters are the minimal structures capable of directing effective TCR signaling. Furthermore, imaging studies have determined that these structures trigger the assembly of oligomeric signaling scaffolds that contain the adapters and effectors required for T‐cell activation. Existing models of T‐cell activation accurately explain the sensitivity and selectivity of antigen recognition. However, these models do not account for important properties of microclusters, including their peripheral formation, size, and movement on the actin cytoskeleton. Here we examine how lipid rafts, galectin lattices, and protein scaffolds contribute to the assembly, function, and fate of TCR microclusters within immune synapses. Finally, we propose a ‘mechanical segregation’ model of signal initiation in which cytoskeletal forces contribute to the lateral segregation of molecules and cytoskeletal scaffolds provide a template for microcluster assembly.
Sleeping through the night: Are extended‐release formulations the answer?
Authors: Calamaro Christina
Published: February 2008

Purpose: To provide an overview of insomnia, including identification and current treatments, as well as review the efficacy and safety of extended‐release sleep medication.

Data sources: Published clinical research and review articles, DSM‐IV criteria, and clinical trials.

Conclusions: Insomnia is a highly prevalent and debilitating sleep disorder, which may present with one or more of the following symptoms: difficulty initiating sleep, difficulty maintaining sleep, or waking too early without being able to return to sleep. Difficulty maintaining sleep throughout the night is the most common symptom of insomnia. The recently approved nonbenzodiazepine hypnotic, zolpidem extended‐release, can be taken as long as medically necessary to improve sleep‐onset and reduce sleep‐maintenance difficulties in insomnia patients, without negatively affecting next‐day functioning.

Implications for practice: Insomnia continues to be an underdiagnosed and undertreated disorder. The nurse practitioner, through routine inquiry about patient sleep habits and consideration of the appropriate treatment of insomnia, can help restore the quality of life of patients experiencing the negative consequences of insomnia.
Posterior reversible encephalopathy syndrome: An emerging clinical entity in adult, pediatric, and obstetric critical care
Authors: McCoy Heather O’Hara
Published: February 2008

Purpose: To describe the signs, symptoms, causative factors, and treatment for posterior reversible encephalopathy syndrome (PRES), an emerging clinical neuroradiologic entity which may be encountered by nurse practitioners in almost any clinical setting.

Data sources: Extensive review of worldwide literature, including peer‐reviewed medical specialty journals, supplemented by an actual case study. Currently, a paucity of information exists in the nursing literature.

Conclusions: PRES occurs as a result of disordered cerebral circulatory autoregulation and/or endothelial dysfunction, usually as a result of acute, intermittent hypertension. Clinical manifestations include mental status change, headache, visual disturbance, and seizures. Characteristic abnormalities in the posterior cerebral white matter, seen best on diffusion‐weighted magnetic resonance imaging, confirm the presence of the syndrome. PRES has been documented worldwide among a diverse patient population, yet many clinicians are still unfamiliar with this diagnosis.

Implications for practice: PRES is a clinical‐radiographic diagnosis that requires close collaboration between the clinician and interpreting radiologist. Rapid identification and appropriate diagnostics are essential, as prompt treatment usually results in reversal of symptoms; permanent neurologic injury or death can occur with treatment delay.
Masowe Migration: A Quest for Liberation in the African Diaspora
Authors: Mukonyora Isabel
Published: February 2008

This article shows how the Shona‐speaking prophet Johane Masowe (1914–1973) adapted Christianity to the difficult human conditions that forced him and his followers to migrate from Zimbabwe during the economic depression of the 1930s. It suggests that the prophet Johane constructs a distinctly African theology of liberation by using the Exodus as symbolic language expressive of human suffering and hope for the redemption of African victims of oppression. The Exodus is used to legitimate Johane's migration from his rural home, Gandanzara, to Harare, Bulawayo and across the border to different cities in southern, central, and east Africa where Masowe Apostles are found today. This article goes beyond the analysis of texts that theologians traditionally use to explain Christianity, to the lived experiences of people addressing problems of displacement through migratory behavior.
The Social Ethic of Religiously Unaffiliated Spirituality
Authors: Chandler Siobhan
Published: February 2008

Today a growing percentage of Westerners are engaged in highly subjective, non‐religiously affiliated forms of spiritual seeking. Since its early beginnings in the 1970s, New Age movement, non‐institutionally mediated forms of spirituality, moved well beyond a restricted esoteric framework into the cultural mainstream. Here, they are more broadly supported and intensified by a robust cultural ethic of individualism and religious antiauthoritarianism. Despite clear indications that this type of spirituality is a religious adaptation or innovation to the ineluctable force of late modernity, many scholars and cultural observers continue to represent it as a weak, socially insignificant form of religious expression that is contributing to a crisis of civic engagement and community mindedness through its over‐emphasis on the self and its experiences. Claims that non‐institutional, non‐dogmatic forms of religiosity promote narcissism and social alienation are scattered throughout the social scientific literature. Yet, little empirical data support these contentions. Building on studies that demonstrate a positive correlation between individualism and civic engagement, this article suggests that future research may well discover that religiously unaffiliated spirituality is in fact a socially engaged religious expression.
Protective Effects of Cyclooxygenase‐2 Inhibitors on Narrow‐band Ultraviolet B‐irradiated Epidermal Ia+ Langerhans Cells and Thy‐1+ Dendritic Epidermal T Cells in Mice†
Authors: Wu Yan , Tai Chang‐Long , Wei Huachen , He Fang , Wang Yakun , Zhao Yuming , Chen Hong‐Duo
Published: February 2008

Cyclooxygenase (COX)‐2 inhibitors are known to be used as chemopreventative agents against certain malignancies. Thus far, there has been very limited information on whether COX‐2 inhibitors protect against chronic narrow‐band UVB (NB‐UVB)‐induced immunosuppression. The present study investigated the effect of nonselective and specific COX‐2 inhibitors, indomethacin and celecoxib, on epidermal Ia+ Langerhans cells (LCs) and Thy‐1+ dendritic epidermal T cells (DETCs) in mice irradiated with NB‐UVB. Sixty female BALB/c mice were divided randomly into the control group (sham) and the experimental groups (irradiated with NB‐UVB for 17 weeks, further divided into five groups according to the diets containing different concentrations of either COX‐2 inhibitors). Alterations in the density and morphology of epidermal Ia+ LCs and Thy‐1+ DETCs in mice were documented using fluorescence microscopy. Chronic NB‐UVB irradiation substantially decreased the density and altered the morphology of the epidermal Ia+ LCs and Thy‐1+ DETCs in control mice. The dietary supplementation of both COX‐2 inhibitors displayed a dosage‐dependent protective effect on the murine dendritic cells irradiated by NB‐UVB. In conclusion, COX‐2 inhibitors protected against chronic NB–UVB‐induced density and morphologic changes in epidermal Ia+ LCs and Thy‐1+ DETCs in mice.
Amino Acid Residues in GRK1/GRK7 Responsible for Interaction with S‐Modulin/Recoverin†
Authors: Torisawa Aya , Arinobu Daisuke , Tachibanaki Shuji , Kawamura Satoru
Published: February 2008

GRK1 is a visual pigment kinase in rods and is essential for inactivation of light‐activated rhodopsin. The GRK1 activity is inhibited by binding of the Ca2+‐bound form of S‐modulin/recoverin. We previously identified the S‐modulin/recoverin site to interact with GRK1. In the present study, we identified its counterpart in GRK1. We synthesized 29 of GRK1 or GRK7 partial peptides that cover the entire sequence of GRK1/GRK7, and examined whether these peptides inhibit S‐modulin/recoverin activity most probably by preoccupying the binding site for GRK1. The inhibition was the greatest with the N‐terminal peptide (p1, aa 3–23 in GRK7). On mutation of each of eight amino acid residues highly conserved in the p1 region of more than 10 orthologs, the inhibition was significantly reduced in the mutation of Leu6, Asn12 and Tyr15. We further examined the binding of the peptides, including mutated ones, to S‐modulin/recoverin with a resonance mirror biosensor. The binding correlated well with the degree of the inhibition by a peptide. The inhibition, therefore, seemed to be due to a direct binding of the kinase peptide to the binding site of active S‐modulin/recoverin. A GRK1 region close to its C‐terminus also seemed to be the binding site for S‐modulin/recoverin.
A prospective, quantitative study on the clinical outcome of inferior alveolar nerve decompression and neurolysis
Authors: Robinson P.P. , Yates J.M. , Smith K.G.
Published: February 2008

Aim:  The management of persistent anaesthesia or dysaesthesia following damage to the inferior alveolar nerve is difficult, and the benefit of interventions is often unclear. We have evaluated the outcome of inferior alveolar nerve decompression and neurolysis in a series of 25 patients, with injuries usually sustained during third molar removal, who had poor spontaneous recovery.

Materials and methods:  The mean age at surgery was 45 years, and most patients were female (21 patients). The mean period between the initial injury and decompression was 28 months, and we assessed the final outcome at 1 year or more after decompression. Assessment included the responses to a series of standard questions, completion of visual analogue scales (VAS) and sensory tests.

Results:  We found that after decompression fewer patients reported pain, and VAS scores were significantly reduced for the level of tingling. Patients also reported better subjective levels of sensation after decompression, and sensory tests confirmed small but significant improvements. The median subjective value of the operation was assessed by patients as 7 (range 0–10).

Conclusions:  These data show that inferior alveolar nerve decompression results in significant reductions in the level of dysaesthesia and improvements in sensation. However, as the overall level of improvement is small, and some patients do not improve, the procedure should only be offered to patients who are significantly affected by their symptoms.
Answering Essay Questions
Authors: DeBuvitz William
Published: February 2008

Most of the homework I have assigned in physics courses has been of the problem-solving type, although I do assign a few essay questions for most chapters. I have also taught qualitative science courses in which most of the homework and exams involved either multiple-choice or essay questions. What I find surprising is that all physics textbooks go into detail on how to solve physics problems (determining what is asked, choosing the proper formula, showing the work clearly, and checking the results) but never say anything about answering essay questions. Teachers and authors might answer my criticism by saying, “Isn't it obvious how to answer an essay question?” Based on my experiences, I do not think it is obvious to a good number of students.
Einstein in Hollywood: Capturing the Scientific Minds of Young Movie Buffs
Authors: Young Chad , Guillot Jamie
Published: February 2008

A number of TPT authors have presented creative uses of movies in physics classrooms.1–4 These authors present wonderful ways to engage students and cause them to look for physics in the movies they watch every week. To assist physics teachers, we have collected more than 60 movie clips and made them available on the Internet at http://www.nicholls.edu/phsc/physics/movies for use in their classrooms.
When Two Balls Are Just One
Authors: Kulp Christopher W. , Biermann Mark L. , Howard Timothy , Klingenberg Kurtis , Ramsey Paul
Published: February 2008

A camcorder can be a powerful tool in pedagogical settings, such as in an introductory physics course or in introducing undergraduates to data collection. In this paper, we discuss our experience using a Panasonic PV-GS150 digital camcorder to analyze the motion of a falling steel ball, with the goal of determining the acceleration due to gravity, g = 9.80 m/s2. When performing this simple experiment, an interesting technical issue arose that led to an excellent teaching opportunity that is based on an unexpected and intriguing method of computing g.
Thermal Patterns in the Snow: Icicles as Indicators of Heat Loss
Authors: Bartlett Albert A.
Published: February 2008

On Dec. 27, 2006, we drove with our children and their families to a cabin we rented on the grounds of the “YMCA of the Rockies” in Estes Park, CO, for a few days of winter relaxation and recreation. On the night of the 27th a snowstorm dropped over half a meter of new snow, creating a beautiful winter wonderland. For the next couple of days the Sun shone brightly but the temperatures stayed well below freezing, so the combination of time and temperature cooperated to produce some spectacular thermal patterns in the snow on the roofs of the buildings. In the following days I walked a great deal, using my new digital camera to photograph these evolving thermal patterns, a subject that first fascinated me more than 30 years ago.1,2 This time the thermal patterns were dramatically complemented by the presence of icicles.
Using Interactive Whiteboard to Enhance Student Learning
Authors: Blanton Patricia
Published: February 2008

Several years ago I became a member of a supportive group of physics teachers trained in the use of a physics teaching pedagogy we have come to call “modeling.” This approach began at Arizona State University under the direction of Dr. David Hestenes. One aspect of the program provides an active listserv for those teachers who are implementing the approach in their teaching of introductory physics. One current discussion topic deals with the use of interactive whiteboards, and I think several of the points that have been posted for discussion are important to make as you consider the use of this technology in your classroom.
Comment on "Clustering by Passing Messages Between Data Points"
Authors: Brusco Michael J. , Köhn Hans-Friedrich
Published: February 2008

Frey and Dueck (Reports, 16 February 2007, p. 972) described an algorithm termed “affinity propagation” (AP) as a promising alternative to traditional data clustering procedures. We demonstrate that a well-established heuristic for the
p
-median problem often obtains clustering solutions with lower error than AP and produces these solutions in comparable computation time.
A Heme Export Protein Is Required for Red Blood Cell Differentiation and Iron Homeostasis
Authors: Keel Siobán B. , Doty Raymond T. , Yang Zhantao , Quigley John G. , Chen Jing , Knoblaugh Sue , Kingsley Paul D. , De Domenico Ivana , Vaughn Michael B. , Kaplan Jerry , Palis James , Abkowitz Janis L.
Published: February 2008

Hemoproteins are critical for the function and integrity of aerobic cells. However, free heme is toxic. Therefore, cells must balance heme synthesis with its use. We previously demonstrated that the feline leukemia virus, subgroup C, receptor (FLVCR) exports cytoplasmic heme. Here, we show that FLVCR-null mice lack definitive erythropoiesis, have craniofacial and limb deformities resembling those of patients with Diamond-Blackfan anemia, and die in midgestation. Mice with FLVCR that is deleted neonatally develop a severe macrocytic anemia with proerythroblast maturation arrest, which suggests that erythroid precursors export excess heme to ensure survival. We further demonstrate that FLVCR mediates heme export from macrophages that ingest senescent red cells and regulates hepatic iron. Thus, the trafficking of heme, and not just elemental iron, facilitates erythropoiesis and systemic iron balance.
Development and Evaluation of Immunochromatographic Assay for Simple and Rapid Detection of
Campylobacter jejuni
and
Campylobacter coli
in Human Stool Specimens
Authors: Kawatsu Kentaro , Kumeda Yuko , Taguchi Masumi , Yamazaki-Matsune Wataru , Kanki Masashi , Inoue Kiyoshi
Published: February 2008

An immunochromatographic assay (Campy-ICA) using a newly generated single monoclonal antibody against a 15-kDa cell surface protein of
Campylobacter jejuni
was developed. When cell suspensions of 86
C. jejuni
strains and 27
Campylobacter coli
strains were treated with a commercially available bacterial protein extraction reagent and the resulting extracts were tested with the Campy-ICA, they all yielded positive results. The minimum detectable limits for the
C. jejuni
strains ranged from 1.8 × 10
4
to 8.2 × 10
5
CFU/ml of cell suspension, and those for the
C. coli
strains ranged from 1.4 × 10
5
to 4.6 × 10
6
CFU/ml of cell suspension. All 26 non-
Campylobacter
species tested yielded negative results with the Campy-ICA. To evaluate the ability of the Campy-ICA to detect
C. jejuni
and
C. coli
in human stool specimens, suspensions of 222 stool specimens from patients with acute gastroenteritis were treated with the bacterial protein extraction reagent, and the resulting extracts were tested with the Campy-ICA. The Campy-ICA results showed a sensitivity of 84.8% (28 of 33 specimens) and a specificity of 100% (189 of 189 specimens) compared to the results of isolation of
C. jejuni
and
C. coli
from the stool specimens by a bacterial culture test. The Campy-ICA was simple to perform and was able to detect
Campylobacter
antigen in a fecal extract within 15 min. These results suggest that Campy-ICA testing of fecal extracts may be useful as a simple and rapid adjunct to stool culture for detecting
C. jejuni
and
C. coli
in human stool specimens.
RespiFinder: a New Multiparameter Test To Differentially Identify Fifteen Respiratory Viruses
Authors: Reijans Martin , Dingemans Gijs , Klaassen Corné H. , Meis Jacques F. , Keijdener Judith , Mulders Brit , Eadie Kimberly , van Leeuwen Willem , van Belkum Alex , Horrevorts Alphons M. , Simons Guus
Published: February 2008

Broad-spectrum analysis for pathogens in patients with respiratory tract infections is becoming more relevant as the number of potential infectious agents is still increasing. Here we describe the new multiparameter RespiFinder assay, which is based on the multiplex ligation-dependent probe amplification (MLPA) technology. This assay detects 15 respiratory viruses in one reaction. The MLPA reaction is preceded by a preamplification step which ensures the detection of both RNA and DNA viruses with the same specificity and sensitivity as individual monoplex real-time reverse transcription-PCRs. The RespiFinder assay was validated with 144 clinical samples, and the results of the assay were compared to those of cell culture and a respiratory syncytial virus (RSV)-specific immunochromatography assay (ICA). Compared to the cell culture results, the RespiFinder assay showed specificities and sensitivities of 98.2% and 100%, respectively, for adenovirus; 96.4% and 100%, respectively, for human metapneumovirus; 98.2% and 100%, respectively, for influenza A virus (InfA); 99.1% and 100%, respectively, for parainfluenza virus type 1 (PIV-1); 99.1% and 80%, respectively, for PIV-3; 90.1% and 100%, respectively, for rhinovirus; and 94.6% and 100%, respectively, for RSV. Compared to the results of the RSV-specific ICA, the RespiFinder assay gave a specificity and a sensitivity of 82.4% and 80%, respectively. PIV-2, PIV-4, influenza B virus, InfA H5N1, and coronavirus 229E were not detected in the clinical specimens tested. The use of the RespiFinder assay resulted in an increase in the diagnostic yield compared to that obtained by cell culture (diagnostic yields, 60% and 35.5%, respectively). In conclusion, the RespiFinder assay provides a user-friendly and high-throughput tool for the simultaneous detection of 15 respiratory viruses with excellent overall performance statistics.
Higher-Order RNA Structural Requirements and Small-Molecule Induction of Tombusvirus Subgenomic mRNA Transcription
Authors: Wang Sheng , Mortazavi Leyla , White K. Andrew
Published: February 2008

Subgenomic (sg) mRNAs are small viral messages that are synthesized by polycistronic positive-strand RNA viruses to allow for the translation of certain viral proteins. Tombusviruses synthesize two such sg mRNAs via a premature termination mechanism. This transcriptional process involves the viral RNA-dependent RNA polymerase terminating minus-strand RNA synthesis prematurely at internal RNA signals during copying of the viral genome. The 3′-truncated minus-strand RNAs generated by the termination events then serve as templates for sg mRNA transcription. A higher-order RNA structure in the viral genome, located just upstream from the termination site, is a critical component of the RNA-based polymerase attenuation signal. Here, we have analyzed the role of this RNA structure in mediating efficient sg mRNA2 transcription. Our results include the following: (i) we define the minimum overall thermodynamic stability required for an operational higher-order RNA attenuation structure; (ii) we show that the distribution of stability within an attenuation structure affects its function; (iii) we establish that an RNA quadruplex structure can act as an effective attenuation structure; (iv) we prove that the higher-order RNA structure forms and functions in the plus strand; (v) we provide evidence that a specific attenuation structure-binding protein factor is not required for transcription; (vi) we demonstrate that sg mRNA transcription can be controlled artificially through small-molecule activation using RNA aptamer technology. These findings provide important new insights into the premature termination mechanism and present a novel approach to regulate the transcriptional process.
Fungi from decayed wood as ectomycorrhizal symbionts of western hemlock
Authors: Kropp Bradley R.
Published: February 2008

Four wood-inhabiting fungi, Byssoporiaterrestris, Cenococcumgeophilum, Pilodermabicolor, and an unidentified isolate, formed mycorrhizae with western hemlock (Tsugaheterophylla (Raf.) Sarg.) in pure culture. Field observations indicate that Cantharellusinfundibuliformis, Chroogomphustomentosus, Galerina sp., and Russula sp. are also mycorrhizal with hemlock growing in rotten wood.
Estimating production of paper birch and utilization by browsers
Authors: Oldemeyer John L.
Published: February 2008

A 4-year study was conducted to develop methods for estimating production and utilization of paper birch (Betulapapyrifera Marsh.) on the Kenai National Wildlife Refuge, Alaska. Twenty-four individual birch saplings were tagged in each of 101 stands. Fall estimates were made of annual production and spring estimates were made of utilization on each tagged sapling. Regression equations were developed from clipped-plant measurements and weights and used to estimate production of each tagged sapling. Diameters of browsed twigs on the tagged saplings were measured and regression equations were developed to estimate how much annual growth had been removed from each sapling. Three estimates of utilization were developed for each stand: percentage current annual growth (CAG) weight browsed, percentage CAG twigs browsed, and percentage birch saplings browsed. These were highly correlated. An estimate of percentage CAG weight browsed usually requires clipping studies; however, that value can be estimated reliably with either of the latter two estimators of use.
The pine wood nematode: a comparison of the situation in the United States and Japan
Authors: Wingfield M. J. , Blanchette R. A. , Nicholls T. H. , Robbins K.
Published: February 2008

The pine wood nematode, Bursaphelenchusxylophilus (Steiner and Buhrer) Nickle, causes a wilt of pines in Japan. Severe damage to forests in Japan have been occurring for the past 30 years. Recently, the nematode has been found on conifers throughout the United States. Little is known of the biology and etiology of the pine wood nematode in North America. At present, there appears to be little threat to native coniferous forests of the United States and Canada. This is indicated by the wide host range and extensive geographic distribution of the nematode, association of the nematode on trees severely weakened by insects and diseases, and presence of the nematode in the United States since the early part of this century. Monoculture of susceptible conifers, offsite plantings and the introduction of potentially more effective vectors could, however, result in an increased damage by the nematode.
A method for evaluating tree wound treatment materials
Authors: Leben Curt , Shigo Alex L. , Hall T. J.
Published: February 2008

Wound closure, discoloration, and decay are evaluated in one stem wound, which is separated into equal parts by a metal divider that provides treatment and control portions.
Forest ecosystems in an old-growth pine–mixed hardwood forest of the Changbai Shan Preserve in northeastern China
Authors: Barnes Burton V. , Xü Zhenbang , Zhao Shidong
Published: February 2008

Landscape ecosystems of a 60-ha area, representative of the pine–mixed hardwood forest of the Changbai Shan Preserve in Jilin Province of northeastern China, were identified, described, and contrasted. Site–species relationships and successional trends were examined together with a comparison of these ecosystems and species with those of northern hardwood forests of eastern North America. Ecosystem components of physiography, soil, and vegetation were used to distinguish two major ecosystem types. The more widespread ecosystem 1 differed from ecosystem 2 in having a flatter topography and more moist and nutrient-rich soil. The overstory of ecosystem 1 was dominated by Tiliaamurensis Rupr., Pinuskoraiensis Sieb. & Zucc, Quercusmongolica Fisch. & Turcz., and Fraxinusmandshurica L., whereas that of ecosystem 2 was dominated primarily by Pinuskoraiensis and Quercusmongolica. Understory species and ground-cover vegetation also reflected the difference in physiography and soil between the two ecosystem types. Six Acer species were recorded; they occurred primarily in the subdominant overstory and the understory of both ecosystems. Without catastrophic disturbance, succession favors the more shade tolerant species in all layers. Pinus and Quercus are rare in the ground cover and understory. Acermono Maxim, is much less dominant than its North American counterpart, Acersaccharum Marsh., in their respective mesic ecosystems in the Changbai Shan forest and forests of western upper Michigan. Fagus and Tsuga, characteristic dominants of northern hardwood forests of eastern North America, are absent. The establishment ecology of Pinuskoraiensis, a five-needled pine with wingless seeds, in the mixed hardwood forest is discussed.
Resistance, tolerance, and yield of western black cottonwood infected by Melampsora rust
Authors: Wang J. , Kamp B.J. van der
Published: February 2008

Potted ramets of 14 western black cottonwood (Populustrichocarpa Torr. & Gray) clones from southern British Columbia were inoculated with Melampsoraoccidentalis H. Jacks to produce a range of disease severities, and their size and dry weight were determined after 1 or 2 years. Response to inoculation varied significantly between clones. Clones from drier interior locations were less resistant than those from coastal or moister interior locations. Local- (within leaf) or systemic-induced resistance was not detected. Yield (total dry weight) decreased linearly with disease severity. Percent reduction in yield was greater than the cumulative percent leaf area infected for all clones. Yield losses were substantial: dry weights of ramets with disease severity levels similar to those experienced by natural cottonwood populations were about 75% of controls; heavily infected ramets were <50% of controls. Stem:root ratios increased rapidly with increasing disease severity in all clones, and at significantly different rates. Severe infection resulted in substantial mortality in the following winter and reduced initial stem volume growth in the following growing season. Tolerance, defined as the relationship between disease severity and yield, varied significantly between clones. The most significant discovery of this study was that tolerance and resistance were correlated, greater tolerance being associated with reduced resistance. The concepts of resistance, tolerance, and disease hazard, as quantified in this study, can be used to predict yield and to select the most appropriate clones for different disease hazard conditions.
Restriction fragment variation in the nuclear ribosomal DNA repeat unit within and between Picearubens and Piceamariana
Authors: Bobola Michael S. , Eckert Robert T. , Klein Anita S.
Published: February 2008

The frequencies of polymorphic restriction fragments for the nuclear ribosomal DNA repeat were compared for 12 provenances of red spruce (Picearubens Sarg.) and 34 provenances of black spruce (Piceamariana (Mill.) B.S.P.). Within an individual as many as five distinct ribosomal DNA repeat unit types could be distinguished. Canonical correlation analysis revealed significant variation of restriction fragment frequencies with a geographic variate comprising latitude and longitude of provenances. Geographic origins accounted for 24.7% of the variation in polymorphic restriction fragments in black spruce and 31.8% of the variation in polymorphic restriction fragments in red spruce. Discriminant analysis, using the restriction fragment frequencies for the ribosomal DNA, was used to develop a classification model for the two species. Tenfold verification of the model produced an average correct classification of 99% for black spruce and 96% for red spruce. Plots of canonical scores for the first and second canonical variâtes clearly separated red spruce from black spruce. This study presents a novel combination of restriction fragment frequency data and multivariate analysis to distinguish species that may not always be differentiated using morphological traits.
NT-pro-BNP during hypoglycemia and hypoxemia in normal subjects: impact of renin-angiotensin system activity
Authors: Due-Andersen R. , Pedersen-Bjergaard U. , Høi-Hansen T. , Olsen N. V. , Kistorp C. , Faber J. , Boomsma F. , Thorsteinsson B.
Published: February 2008

Brain-derived natriuretic peptide (BNP) is a cardioprotective peptide released, together with the inactive NH2-terminal part of its prohormone (NT-pro-BNP), in response to different kinds of myocardial stress. Hypoglycemia and hypoxemia are conditions that threaten cellular function and hence potentially stimulate BNP release. BNP interacts with the renin-angiotensin system (RAS). The aim of this study was, therefore, to explore if basal RAS activity has an impact on NT-pro-BNP concentrations during myocardial stress induced by hypoglycemia and hypoxemia. From a cohort of 303 healthy young men, 10 subjects with high-RAS activity and 10 subjects with low-RAS activity (age 26 ± 1 yr; mean ± SE) were studied in a single-blinded, randomized, counterbalanced, crossover study on three occasions separated by at least 3 wk: 1) hypoglycemia (mean nadir plasma glucose 2.7 ± 0.5 mmol/l), 2) hypoxemia (mean nadir Po2 5.8 ± 0.5 kPa), and 3) normoglycemic normoxia (control). NT-pro-BNP was measured at baseline, during the stimuli, and in the recovery phase. Hypoxemia was associated with a 9% increase in NT-pro-BNP from 2.2 ± 1.5 pmol/l at baseline to 2.4 ± 1.5 pmol/l during hypoxemia ( P < 0.001). Hypoglycemia did not affect the NT-pro-BNP level. RAS activity had no impact on NT-pro-BNP levels during hypoglycemia and hypoxemia. Hypoxemia, but not hypoglycemia, stimulates NT-pro-BNP. This indicates that cardiac defense mechanisms against hypoglycemia, if any, are probably different from those against hypoxemia. Basal RAS activity had no impact on NT-pro-BNP levels.
Phenotype Associated with the H626P Mutation and Other Changes in the TGFBI Gene in Czech Families
Authors: Liskova Petra , Klintworth Gordon K. , Bowling Brandy L. , Filipec Martin , Jirsova Katerina , Tuft Stephen J. , Bhattacharya Shomi S. , Hardcastle Alison J. , Ebenezer Neil D.
Published: February 2008

Aims: To evaluate mutations in the transforming-growth-factor-β-induced (TGFBI) gene in patients of Czech origin with autosomal dominant corneal dystrophies. Methods: The coding sequence of the TGFBI gene was analysed in 22 affected Czech individuals from 7 apparently unrelated families. Comparison of phenotype to genotype was performed. Results: A H626P mutation, previously only described in a family with a variant of lattice corneal dystrophy (LCD), was detected in one family with superficial geographic corneal opacities. Light microscopy of 2 samples obtained following either a prior superficial keratectomy or keratoplasty showed amyloid but no fuchsinophilic deposits. In a family with LCD type I, an R124C mutation was identified. The R124L mutation was shown to be causative of Reis-Bücklers corneal dystrophy in 2 families. A family with Thiel-Behnke corneal dystrophy exhibited an R555Q mutation. In 2 families with granular corneal dystrophy type I, the typical R555W change was identified. Conclusion: The phenotype of the family with the H626P mutation differed from the phenotype previously reported for this change.