bluuebunny/crossref_metadata_2025 huggingface dataset:
Work factors as predictors of intense or disabling low back pain; a prospective study of nurses’ aides
Authors: Eriksen W , Bruusgaard D , Knardahl S
Published: April 2004

Aims:To identify the work factors that predict intense low back pain (LBP) and LBP related sick leaves in nurses’ aides.

Methods:The sample comprised 4266 randomly selected Norwegian nurses’ aides, not bothered or only a little bothered by LBP during the previous three months, and not on sick leave when completing a mailed questionnaire in 1999. Of these, 3808 (89.3%) completed a second questionnaire 3 months later and 3651 (85.6%) completed a third questionnaire 15 months later. Intensity of low back symptoms and certified sick leaves attributed to LBP during the observation period were assessed by self reports at the follow ups.

Results:After adjustments for LBP during the three months prior to baseline, baseline health complaints, demographic and familial factors, and a series of physical, psychological, and social work factors, logistic regression analyses revealed the following associations: intense low back symptoms were predicted by frequent positioning of patients in bed, perceived lack of support from immediate superior, and perceived lack of pleasant and relaxing culture in the work unit. LBP related sick leaves were predicted by frequent handling of heavy objects, medium level of work demands, perceived lack of supportive and encouraging culture in the work unit, working night shifts, and working in a nursing home. Long term LBP related sick leaves were associated with changes of work or work tasks during the observation period that resulted in a perceived reduction of support and encouragement at work.

Conclusions:Not only frequent mechanical exposures, but also organisational, psychological, and social work factors, such as night shift work, perceived lack of support from superior, and perceived lack of a pleasant and relaxing or supporting and encouraging culture in the work unit, are associated with an increased risk of intense low back symptoms and LBP related sick leaves in nurses’ aides.
Prevalence of chronic fatigue syndrome-like caseness in the working population: results from the Maastricht cohort study: Table 1
Authors: Huibers M J H , Kant IJ , Swaen G M H , Kasl S V
Published: April 2004

Aim:To determine the prevalence of chronic fatigue syndrome (CFS)-like caseness in the working population.

Methods:Using data from the prospective Maastricht Cohort Study on Fatigue at Work, the prevalence and incidence of CFS-like cases (employees meeting research criteria for CFS) were determined among 5499 employees who responded to the follow up assessment 3 years and 8 months after baseline.

Results:Of the 5499 employees, 199 (3.6%) were identified as CFS-like cases. By deleting possible CFS-like cases at baseline, the annual incidence of CFS-like caseness was estimated to be 85 per 10 000. Twenty employees (0.36%) reported having been diagnosed with CFS by a physician.

Conclusions:The prevalence of CFS-like cases (3.6%) was considerably higher than the prevalence of CFS reported in previous studies (0.006–3%). These findings suggest that the CFS-like caseness may be underdetected in the working population and perhaps in other populations as well.
Perceived risk from occupational stress: a survey of 15 European countries: Table 1
Authors: Daniels K
Published: April 2004

Aims:To examine the ranking of workers in 15 European countries with respect to the extent that work is perceived to influence occupational stress.

Methods:International interviewer administered cross-sectional survey. Control variables included demographics, perceived job conditions, and job satisfaction. A sample of working adults (n = 11 054) from 15 European countries were studied.

Results:In three statistical models, the British sample ranked in the lower half of the distribution, where higher rankings indicated greater perceived risk of occupational stress. The Greek sample was ranked first in all models, and the Irish sample ranked last in all models.

Conclusions:Since there is sociocultural variation in the perceived risk from occupational stress, it is possible that sociocultural factors influence the accuracy of national monitoring systems and the success of occupational health policy in this area.
Cancer incidence and mortality of isocyanate exposed workers from the Swedish polyurethane foam industry: updated findings 1959–98
Authors: Mikoczy Z , Welinder H , Tinnerberg H , Hagmar L
Published: April 2004

Aims:To assess whether cancer incidence and mortality in chronic obstructive lung diseases were increased in the Swedish polyurethane foam industry cohort, updated with 11 more years of follow up.

Methods:The mortality and cancer incidence (1959–98) experienced by a cohort of 4175 male and female employees employed for at least one year in the period 1959–87 at one of nine Swedish polyurethane foaming plants were investigated. Comparisons were based on calendar year, sex, and five-year age group specific mortality and incidence rates for Sweden. Workplaces and job tasks were categorically assessed for exposure to toluene diisocyanate (TDI) and methylene diphenyldiisocyanate (MDI) by occupational hygienists.

Results:Fewer cancer cases than expected were observed, but the lung cancer incidence was enhanced in women. Women with “apparent exposure” to TDI or MDI did not, however, have a higher lung cancer incidence than those with “no or low exposure”. Moreover, a nested case referent study did not find that polyurethane dust exposure had been more prevalent among the female lung cancer cases than among referents. No increased mortality in chronic obstructive lung diseases was observed in the cohort.

Conclusions:Results support the findings from two other cohort studies of an increased lung cancer risk among female workers in the polyurethane foam manufacturing industry. Chance or confounding from smoking are not obvious explanations for the coherent findings. However, the study was not able to link isocyanate exposed employment with lung cancer risk.
Changing trends in US mesothelioma incidence
Authors: Weill H , Hughes J M , Churg A M
Published: April 2004

Aims:To report the temporal pattern and change in trend of mesothelioma incidence in the United States since 1973.

Methods:The Surveillance, Epidemiology, and End Results (SEER) programme of the National Cancer Institute has since 1973 provided annual age adjusted incidence for mesothelioma in representative cancer registries dispersed throughout the USA. SEER data are analysed to describe the trend of male mesothelioma incidence in the USA.

Results:The US male mesothelioma incidence data indicate that after two decades of increasing incidence, a likely decline has been observed since the early 1990s, when a highly significant change in the upward course occurred.

Conclusions:Increasing male mesothelioma incidence for many years was undoubtedly the result of exposure to asbestos. The high mesothelioma risk was prominently influenced by exposure to amphibole asbestos (crocidolite and amosite), which reached its peak usage in the 1960s and thereafter declined. A differing pattern in some other countries (continuing rise in incidence) may be related to their greater and later amphibole use, particularly crocidolite. The known latency period for the development of this tumour provides biological plausibility for the recent decline in mesothelioma incidence in the USA. This favourable finding is contrary to a widespread fear that asbestos related health effects will show an inevitable increase in coming years, or even decades.
Graffenrieda emarginata (Melastomataceae) forms mycorrhizas with Glomeromycota and with a member of the Hymenoscyphus ericae aggregate in the organic soil of a neotropical mountain rain forest
Authors: Haug Ingeborg , Lempe Johanne , Homeier Jürgen , Weiß Michael , Setaro Sabrina , Oberwinkler Franz , Kottke Ingrid
Published: April 2004

Graffenrieda emarginata (Ruiz & Pav.) Triana (Melastomataceae) was found to be the most frequent tree on the nutrient-poor organic soil in a species-rich tropical mountain rain forest of southern Ecuador. Our studies revealed that the rootlets are symbiotically associated with arbuscular mycorrhizal fungi and simultaneously form ectomy corrhizas displaying a superficial Hartig net but no hyphal mantle. Molecular phylogeny revealed a multitude of previously unknown glomeromycete sequence types. Ultrastructure of the ectomycorrhiza-forming fungus indicated an ascomycete, and molecular phylogenetic studies identified the fungal symbiont as a new taxon within the Hymenoscy phus ericae (Read) Korf & Kernan aggregate (Ascomycota). The mycorrhizal state of G. emarginata is considered crucial for its competitiveness and abundance in these sites.Key words: arbuscular mycorrhiza, ectomycorrhiza, Glomeromycota, Hymenoscyphus ericae aggregate, neotropical mountain rain forest, Ecuador.
Rules of crown development in the clonal shrub Vaccinium hirtum in a low-light understory: a quantitative analysis of architecture
Authors: Kawamura Koji , Takeda Hiroshi
Published: April 2004

The rules of crown development in the clonal shrub Vaccinium hirtum Thunb. in a low-light understory were identified by architectural analysis, and the structure and dynamics of current-year shoots were quantified. Development started from an initial orthotropic axis, which forked into plagiotropic axes; consequently, arched stems were formed. Subsequently, a new orthotropic shoot arose from the dormant meristem on the stem. The process from orthotrophy to plagiotrophy was then repeated. Ramets developed vertically as a result of the repeated formation of such orthotropic shoots and reached a maximum height of about 2 m. These processes were mainly characterized by the sequential change from orthotrophy to plagiotrophy in stem orientation and by a sequential reduction in shoot growth, in which a long shoot forked into shorter shoots with increasing allocation to leaves relative to stems. These rules may be adaptive for efficient light capture under conditions of low light availability, in terms of a low degree of self-shading and low cost of supporting tissue. Simultaneously, these rules worked to restrict the developmental potential of crowns, including the lateral expansion of crowns and the longevity of branch systems. This may be associated with a shrub-specific, throwaway design for stems that are expendable in high-stress environments.Key words: crown architecture, branching, leaf display, architectural unit, reiteration.
Effect of arbuscular mycorrhizal fungi and phosphorus fertilization on the post vitro growth and yield of micropropagated strawberry grown in a sandy loam soil
Authors: Sharma Mahaveer P , Adholeya Alok
Published: April 2004

Strawberries (Fragaria ×ananassa Duch.) grown in alfisols of semiarid areas in India results in suboptimal yields. Low organic carbon and low phosphorus (P) availability, in addition to high P fixation, affects P availability drastically, even when it is applied externally. The benefit to the yield of micropropagated strawberry Fragaria ×ana nassa 'Pajaro' through inoculation with arbuscular mycorrhizal (AM) fungi and P application was examined in a field experiment. AM response was evaluated at four doses of P (50, 100, 150, and 200 kg P·ha1) in a high P-fixing capacity and P-deficient alfisol. At harvest, all inoculated plants, except those at the highest level of applied P (200 kg·ha1), had larger fruit yields per plant, unit mass, number of runners, higher shoot dry matter, and shoot P content. However, the AM response as measured by yield varied with P concentration. Inoculated plants had a significantly greater fruit yield when grown at 150 kg P·ha1, and the yield was comparable with uninoculated plants grown at 200 kg P·ha1. The external P requirements were 71 kg·ha1 for mycorrhizal and 106 kg·ha1 for nonmycorrhizal strawberry plants to obtain 90% of the maximum fruit yield. In terms of P fertilization, this corresponds to a savings of 35 kg·ha1. The percent mycorrhizal root length colonization, both in inoculated and noninoculated plants, was not found to differ significantly with P application.Key words: strawberry, P fertilization, mycorrhizal dependency.
Developmental progression of photosystem II electron transport and CO2 uptake in Spartina alterniflora, a facultative halophyte, in a northern salt marsh
Authors: Baerlocher Mark O , Campbell Douglas A , Ireland Robert J
Published: April 2004

Leaves of Spartina alterniflora Loisel, a halophytic salt marsh grass, show rapid changes in photosynthetic performance and allocation of carbon and nitrogen resources to key macromolecules during the growing season. Photo system II (PSII) electron transport correlated primarily with the developmental state of the plants and less with the ambient temperature. The ratio of gross CO2 uptake to PSII electron transport showed high interleaf variation but rose steeply to about 0.22 mol CO2·mol PSII electrons1 through June to late July, with subsequent decline. Seasonal variation in CO2 per PSII electrons correlated with the pattern of maximum capacity for CO2 uptake. RuBisCO (ribulose-1,5-bisphosphate carboxylase-oxygenase) and chlorophyll (Chl) (µmol·m2) peaked in early June, before the period of maximum leaf elongation. RuBisCO then declined through net dilution as the leaves elongated to maximal length in mid-July. RuBisCO and Chl levels stabilized once leaf elongation stopped in mid-July, but from mid-August onward the leaves showed net loss of RuBisCO and Chl. The plants thus show a developmental program of early remobili zation of nitrogenous macromolecules from leaves even though the plants thereby forego maximal photo synthetic performance during 75 d in late summer and early autumn, when temperature and light are near optimal. Key words: electron transport, photosynthesis, PSII, RuBisCO, Spartina.
Phylogeny ofBrayaandNeotorularia(Brassicaceae) based on nuclear ribosomal internal transcribed spacer and chloroplasttrnL intron sequences
Authors: Warwick Suzanne I , Al-Shehbaz Ihsan A , Sauder Connie , Harris James G , Koch Marcus
Published: April 2004

Sequence data from the nuclear ribosomal internal transcribed spacer (ITS) region and the chloroplast trnL intron were used to examine the evolutionary relationships and generic delimitations of Braya, Neotorularia, Dichasianthus, and Sisymbriopsis. Several species, especially the North American - Asian Braya (= Neotorularia) humilis (C.A. Mey.) B.L. Rob., were previously assigned to more than one genus. Sequence data were obtained from all Braya species, except Braya pilosa Hook., seven species of Neotorularia, one of Dichasianthus, and two of Sisymbriopsis. Maximum parsimony analyses showed a poly phyletic origin for Neotorularia, with the genus split into three or four major clades. For both the ITS and trnL sequence data, three species (Neotorularia brachycarpa (Vassilcz.) Hedge & J. Léonard, Neotorularia gamosepala (Hedge) O'Kane & Al-Shehbaz, and Neotorularia humilis (C.A. Mey.) Hedge & J. Léonard) fell within the Braya clade; Neotorularia korolkowii (Regel & Schmalh.) Hedge & J. Léonard formed a separate clade with Dichasianthus subtilissimus (Popov) Ovcz. & Yunussov, while Neotorularia torulosa (Desf.) Hedge & J. Léonard, Neotorularia contor tuplicata (Stephan ex Willd.) Hedge & J. Léonard, Neotorularia dentata (Freyn & Sint.) Hedge & J. Léonard, and Neotorularia tetracmoides (Boiss. & Hausskn.) Hedge & J. Léonard formed either one clade (trnL data) or two clades (ITS data). Sisymbriopsis was not monophyletic, although ITS and trnL data showed a weakly supported relationship between Sisymbriopsis mollipila (Maxim.) Botsch. and one of the Neotorularia clades. Except for Braya forrestii W.W. Sm., which is well supported as sister to the remainder of the Braya clade (ITS data), ITS and trnL sequences showed poor resolution within Braya. Additive ITS sequences indicated allopolyploid origins for Braya fernaldii Abbe, Braya longii Fernald, and three accessions of Braya glabella Richardson (all species with 2n = 56). Morphology and molecular data strongly suggest expanding Braya to include N. humilis, N. brachycarpa, and N. gamosepala; delimiting Neotorularia to include N. torulosa, N. contortuplicata, N. dentata, N. korolkowii, N. tetracmoides, D. subtilissimus, and S. mollipila; and revising Sisymbriopsis.Key words: Braya, Neotorularia, Dichasianthus, Sisymbriopsis, ITS, trnL, Brassicaceae.
Modules of reproduction in females of the dioecious shrubOemleria cerasiformis
Authors: Mitchell Matthew GE , Antos Joseph A , Allen Geraldine A
Published: April 2004

Plants are composed of modules that may be integrated to varying degrees. To examine the extent of integration for photosynthate in female Oemleria cerasiformis (H. & A.) Landon at different times during reproduction, we defoliated terminal branch systems at two scales (0.25 and 1.0 m) just after flowering. Fruit set and mass in the current year were unaffected by defoliation, indicating that developing fruits were strong sinks that could effectively draw on photosynthate from leaves at least 1 m away. In the subsequent year, however, defoliated branches grew very little and produced few flowers and almost no fruits, indicating that storage, growth, and the initiation of flowers and fruit did not utilize carbon resources from leaves only 0.25 m away. Thus, there is no single module size for photosynthate in O. cerasiformis. Because fruits are a strong sink that can draw carbon resources from a considerable distance, high fruit set followed by adverse conditions can lead to generalized resource depletion within a plant, which may result in mortality and contribute to the male-biased sex ratios often observed in O. cerasiformis.Key words: costs of reproduction, defoliation, fruit set, fruit mass, integrated physiological units.
RESULTS ON THE CKM ANGLE ϕ1 (β)
Authors: BROWDER T. E.
Published: April 2004

I review results related to the CKM angle ϕ1 (β). These results include recent measurements of CP-violation from the BaBar and Belle experiments in [Formula: see text], [Formula: see text] and [Formula: see text] processes.
MIXINGS, LIFETIMES, SPECTROSCOPY AND PRODUCTION OF HEAVY FLAVOR AT THE TEVATRON
Authors: PITTS K. T.
Published: April 2004

The Fermilab Tevatron offers unique opportunities to perform measurements of the heavier B hadrons that are not accessible at the ϒ(4S) resonance. In this summary, we describe some recent heavy flavor results from the DØ and CDF collaborations and discuss prospects for future measurements.
QCD AND HEAVY HADRON DECAYS
Authors: BUCHALLA G.
Published: April 2004

We review recent developments in QCD pertaining to its application to weak decays of heavy hadrons. We concentrate on exclusive rare and nonleptonic B-meson decays, discussing both the theoretical framework and phenomenological issues of current interest.
MEASUREMENTS WITH POLARIZED HADRONS
Authors: SHIBATA T.-A.
Published: April 2004

Recent progress in physics with polarized hadrons is described with the emphasis on the spin structure of the nucleon. The nucleon spin problem, which was discovered by EMC in 1988, is now being studied in various experiments. Flavor separation of the quark helicity distributions has been made. Recent observations of asymmetries in deeply virtual Compton scattering (DVCS) and exclusive meson productions provide possibilities to access the total angluar momentum carried by quarks in the framework of generalized parton distributions. Single spin azimuthal asymmetries observed in semi-inclusive measurements provide a new handle to determine the transverse quark distributions which are basic but have never been measured so far.
RELATIVISTIC HEAVY-ION COLLISIONS: RECENT RESULTS FROM RHIC
Authors: HARDTKE D.
Published: April 2004

High energy collisions of heavy nuclei at the Relativistic Heavy-Ion Collider permit the study of nuclear matter at extreme densities and temperatures. Selected experimental highlights from the early RHIC program are presented. Measurements of the total multiplicity in heavy-ion collisions show a surprising similarity to measurements in e+e- collisions after nuclear geometry is taken into account. RHIC has sufficient center-of-mass energy to use large transverse momentum particles and jets as a probe of the nuclear medium. Signatures of "jet quenching" due to radiative gluon energy loss of fast partons in a dense medium are observed for the first time at RHIC. In order to account for this energy loss, initial energy densities of 30-100 times normal nuclear matter density are required.
WIMP/NEUTRALINO DIRECT DETECTION
Authors: DE JÉSUS M.
Published: April 2004

The most popular candidate for non-baryonic dark matter is the neutralino. More than twenty experiments are dedicated to its direct detection. This review describes the most competitive and promising experiments with different detection techniques. The most recent results are presented with some prospects for the near future.
ANISOTROPIC BRANE COSMOLOGIES WITH EXPONENTIAL POTENTIALS
Authors: AGUIRREGABIRIA J. M. , LAZKOZ RUTH
Published: April 2004

We study Bianchi I type brane cosmologies with scalar matter self-interacting through combinations of exponential potentials. Such models correspond in some cases to inflationary universes. We discuss in detail the conditions for accelerated expansion to occur: in particular, we show that the condition which is necessary and sufficient for inflation in the relativistic version of the models is not sufficient in the brane case. Another peculiar feature of the models is that the relationship between the value of the scale factor at the beginning of inflation and the equation of state is very different from what one finds in the relativistic framework. We also analyze the influence of the value of the anisotropy and the brane tension, and show that the associated effects become negligible in the late time limit, those related to the anisotropy disappearing earlier. This study focuses mainly on single field models, but we also consider a generalization yielding models with multiple non-interacting fields and examine their features briefly. We conclude that, in the brane scenario, an increase in the number of fields assists inflation, as happened in general relativity.
ANALYSIS OF THE STATIC AND SPHERICALLY-SYMMETRIC SOLUTION IN NDL THEORY OF GRAVITATION
Authors: NOVELLO M. , BERGLIAFFA S. E. PEREZ , HIBBERD K. E.
Published: April 2004

We investigate the static solution with spherical symmetry of a member of a recently proposed class of field theories of gravitation. In this so-called NDL theory, matter interacts with gravity in accordance with the Weak Equivalence Principle, while gravitons have a nonlinear self-interaction. It is shown that the predictions obtained from this solution agree with those of General Relativity in the three classic tests. There are potential differences in the strong-field limit, which we illustrate by proving that this theory does not allow the existence of static and spherically symmetric black holes.
IMPROVING LLR TESTS OF GRAVITATIONAL THEORY
Authors: WILLIAMS JAMES G. , TURYSHEV SLAVA G. , MURPHY THOMAS W.
Published: April 2004

Accurate analysis of precision ranges to the Moon has provided several tests of gravitational theory including the Equivalence Principle, geodetic precession, parameterized post-Newtonian (PPN) parameters γ and β, and the constancy of the gravitational constant G. Since the beginning of the experiment in 1969, the uncertainties of these tests have decreased considerably as data accuracies have improved and data time span has lengthened. We are exploring the modeling improvements necessary to proceed from cm to mm range accuracies enabled by the new Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) currently under development in New Mexico. This facility will be able to make a significant contribution to the solar system tests of fundamental and gravitational physics. In particular, the Weak and Strong Equivalence Principle tests would have a sensitivity approaching 10-14, yielding sensitivity for the SEP violation parameter η of ~3×10-5, v2/c2 general relativistic effects would be tested to better than 0.1%, and measurements of the relative change in the gravitational constant, Ġ/G, would be ~0.1% the inverse age of the universe. Having this expected accuracy in mind, we discusses the current techniques, methods and existing physical models used to process the LLR data. We also identify the challenges for modeling and data analysis that the LLR community faces today in order to take full advantage of the new APOLLO ranging station.
Nerve Injury about the Shoulder in Athletes, Part 1
Authors: Safran Marc R.
Published: April 2004

Nerve injuries about the shoulder in athletes are being recognized with increasing frequency. Prompt and correct diagnosis of these injuries is important to treat the patient and to understand the potential complications and natural history so as to appropriately counsel athletes. This 2-part article is a review and an overview of the current state of knowledge regarding some of the more common nerve injuries seen about the shoulder in athletes.
Live imaging of nuage and polar granules: evidence against a precursor-product relationship and a novel role for Oskar in stabilization of polar granule components
Authors: Snee Mark J. , Macdonald Paul M.
Published: April 2004

Nuage, a germ line specific organelle, is remarkably conserved between species, suggesting that it has an important germline cell function. Very little is known about the specific role of this organelle, but in Drosophila three nuage components have been identified, the Vasa, Tudor and Aubergine proteins. Each of these components is also present in polar granules, structures that are assembled in the oocyte and specify the formation of embryonic germ cells. We used GFP-tagged versions of Vasa and Aubergine to characterize and track nuage particles and polar granules in live preparations of ovaries and embryos. We found that perinuclear nuage is a stable structure that maintains size, seldom detaches from the nuclear envelope and exchanges protein components with the cytoplasm. Cytoplasmic nuage particles move rapidly in nurse cell cytoplasm and passage into the oocyte where their movements parallel that of the bulk cytoplasm. These particles do not appear to be anchored at the posterior or incorporated into polar granules, which argues for a model where nuage particles do not serve as the precursors of polar granules. Instead, Oskar protein nucleates the formation of polar granules from cytoplasmic pools of the components shared with nuage. Surprisingly, Oskar also appears to stabilize at least one shared component, Aubergine, and this property probably contributes to the Oskar-dependent formation of polar granules. We also find that Bruno, a translational control protein, is associated with nuage, which is consistent with a model in which nuage facilitates post transcriptional regulation by promoting the formation or reorganization of RNA-protein complexes.
Quantitative analysis of phagolysosome fusion in intact cells: inhibition by mycobacterial lipoarabinomannan and rescue by an 1α,25-dihydroxyvitamin D3–phosphoinositide 3-kinase pathway
Authors: Hmama Zakaria , Sendide Khalid , Talal Amina , Garcia Rosa , Dobos Karen , Reiner Neil E.
Published: April 2004

Macrophage cell membranes were labeled with PKH26 and subsequently incubated with latex beads to generate phagosomes surrounded by a red-fluorescent membrane suitable for flow cytometry. Following cell disruption and partial purification of phagosomes, these vesicles were readily distinguished from both cell debris and free beads released from disrupted vacuoles. Flow cytometry analysis of phagosomes stained with specific mAbs and FITC-labeled secondary antibodies showed progressive acquisition of both Rab7 and LAMP-1 consistent with movement along the endocytic pathway. Alternatively, macrophages were preloaded with the lysosomal tracer FITC-dextran before membrane labeling with PKH and incubation with latex beads. Phagosome-lysosome fusion was then quantified on the basis of the colocalization of red and green signals. Using these flow cytometry-based systems, we showed that co-internalization of beads with lysates of Mycobacterium tuberculosis, but not lysates from the nonpathogenic organism Mycobacterium smegmatis, markedly decreased phagosome acquisition of Rab7 and LAMP-1 and vesicle fusion with FITC-dextran-loaded lysosomes. Inhibition of phagolysosome fusion could be attributed, at least in part, to the mycobacterial cell wall glycolipid lipoarabinomannan, and further analysis showed complete rescue of phagosome maturation when cells were pretreated with vitamin D3 before exposure to lipoarabinomannan. Moreover, the ability of vitamin D3 to reverse the phenotype of phagosomes in the presence of the glycolipid was completely abrogated by LY-294002, suggesting that vitamin D3 promotes phagolysosome fusion via a phosphoinositide 3-kinase signaling pathway.

These findings establish a robust platform technology based on labeling of phagocyte cell membranes and flow cytometry capable of supporting broad-based screens to identify microbial and other bioactive compounds that influence phagosome biology.
Sticky worms: adhesion complexes inC. elegans
Authors: Cox Elisabeth A. , Hardin Jeff
Published: April 2004

Caenorhabditis elegans is a powerful model system for investigating the establishment, regulation and function of adhesive structures in vivo. C. elegans has several adhesion complexes related to those in vertebrates. These include: (1) epithelial apical junctions, which have features of both adherens and tight junctions; (2) dense bodies, which are muscle-attachment structures similar to focal adhesions; (3) fibrous organelles, which resemble hemidesmosomes and mediate mechanical coupling between tissues; and (4) a putative dystrophin-glycoprotein complex that has potential roles in muscle function and embryogenesis. Recent work has increased our understanding of these structures and has given new insights into the functions of their vertebrate counterparts.
Effect of Electronic ANR and Conventional Hearing Protectors on Vehicle Backup Alarm Detection in Noise
Authors: Casali John G. , Robinson Gary S. , Dabney Erika Christian , Gauger Dan
Published: April 2004

An experiment was conducted wherein masked thresholds (using ascending method of limits) for a backup alarm were obtained in pink and red noise at 85 and 100 dBA for 12 participants immersed in a probability monitoring task and wearing a conventional passive hearing protection device (HPD, an earmuff or a foam earplug), an active noise reduction (ANR) headset, or no HPD at all (only in 85 dBA noise). Results revealed statistically significant between-HPD differences in red noise (from 2.3 to 3.1 dB) and in the 100-dBA noise level (from 2.6 to 4.3 dB). An additional finding, which corroborates other studies using different protocols, was that masked thresholds in 85-dBA noise were significantly lower (from 3.2 to 4.4 dB) for the occluded conditions (wearing an HPD) than for the open-ear (unoccluded) condition. This result refutes the belief among many normal-hearing workers that the use of HPDs in relatively low levels of noise compromises their ability to hear necessary workplace sounds. Actual or potential applications of this research include (a) the selection of appropriate HPDs for low-frequency-biased noise exposures wherein signal detection is important and (b) gaining insight into the appropriateness of ANR-based HPDs for certain industrial noise environments.
Effects of Organizational Scheme and Labeling on Task Performance in Product-Centered and User-Centered Retail Web Sites
Authors: Resnick Marc L. , Sanchez Julian
Published: April 2004

As companies increase the quantity of information they provide through their Web sites, it is critical that content is structured with an appropriate architecture. However, resource constraints often limit the ability of companies to apply all Web design principles completely. This study quantifies the effects of two major information architecture principles in a controlled study that isolates the incremental effects of organizational scheme and labeling on user performance and satisfaction. Sixty participants with a wide range of Internet and on-line shopping experience were recruited to complete a series of shopping tasks on a prototype retail shopping Web site. User-centered labels provided a significant benefit in performance and satisfaction over labels obtained through company-centered methods. User-centered organization did not result in improved performance except when the label quality was poor. Significant interactions suggest specific guidelines for allocating resources in Web site design. Applications of this research include the design of Web sites for any commercial application, particularly E-commerce.
Linguistic and Location Effects in Compliance with Pesticide Warning Labels for Amateur and Professional Users
Authors: Edworthy Judy , Hellier Elizabeth , Morley Nicola , Grey Clare , Aldrich Kirsteen , Lee Andrew
Published: April 2004

Three studies explored amateur and professional users' compliance with pesticide warning labels. Professionals were classified as people working in a profession in which the use of pesticides is a necessary part of their job. Amateurs used pesticides only in their leisure time. The first study showed that the wording used affected perception of the appropriateness of hazard statements, one of the most effective variations being the use of the personal pronoun (statements beginning “You should...”). The location of warning information was also found to affect actual compliance: Compliance increased when warning information was presented in the directions for use section. A supplemental directive increased compliance only for professional users. In a final study, “best-case” and “worst-case” linguistic variations were combined with best-case and worst-case locations for safety information. Instruction statements using the personal pronoun and presented in the directions for use section resulted in the highest levels of compliance. The differences in compliance between amateur and professional users are interpreted within the framework of Rasmussen's (1986) distinction among skill-, rule-, and knowledgebased behavior. Actual or potential applications of this research include the design of warning labels and safety information.
Detection of Temporal Delays in Visual-Haptic Interfaces
Authors: Vogels Ingrid M. L. C.
Published: April 2004

This paper addresses the question of how large the temporal delay between a visual and a haptic stimulus may be such that the stimuli are still perceived as being synchronous. Participants had to judge whether the moment at which a graphical object collided with a virtual wall occurred simultaneously with the moment at which a force was felt through a force feedback joystick. Participants either moved the joystick to drive the object (active touch) or held the joystick in a steady position while the object moved by itself (passive touch). Participants were found to be very sensitive to visual-haptic time delays. Sensitivity was higher for passive touch than for active touch. The minimum delay at which participants judged the stimuli as asynchronous was on average 45 ms. The delay at which the proportion of synchronous judgments reached a maximum was on average close to zero. The results indicate that the temporal accuracy of visual-haptic interfaces has to meet stringent requirements in order to optimize the overall realism that users experience. Actual or potential applications of this research include teleoperation, medical training, computer-aided-design, and scientific visualization.
Foveal Task Complexity and Visual Funneling
Authors: Murata Atsuo
Published: April 2004

The current study was designed to examine whether increasing foveal task complexity would cause the functional field to shrink as a result of a visual funneling effect. Using 8 male participants, the study examined whether the effects of foveal task complexity on peripheral performance was most pronounced at the far periphery. The response time to an addition task using foveal vision tended to increase with the increase of the visual angle. The percentage correct, however, did not differ among 3 levels of task complexity or among 4 levels of visual angle. The miss rate in the peripheral vision task tended to increase with the increase in not only the complexity of the foveal task but also the visual angle. This is indicative of visual funneling. However, greater funneling was not necessarily observed for response time. In this study, response time was not a sensitive measure of visual funneling. Actual or potential applications of this research include safe driving and other vigilance tasks.
“Conflicting” Motion Cues to the Visual and Vestibular Self- Motion Systems Around 0.06 Hz Evoke Simulator Sickness
Authors: Duh Henry Been-Lirn , Parker Donald E. , Philips James O. , Furness Thomas A.
Published: April 2004

The basic question this research addressed was, how does simulator sickness vary with simulated motion frequency? Participants were 11 women and 19 men, 20 to 63 years of age. A visual self-motion frequency response curve was determined using a Chattecx posture platform with a VR4 head-mounted display (HMD) or a back-projected dome. That curve and one for vestibular self-motion specify a frequency range in which vestibular and visual motion stimuli could produce conflicting self-motion cues. Using a rotating chair and the HMD, a third experiment supported (p < .01) the hypothesis that conflicting cues at the frequency of maximum “crossover” between the curves (about 0.06 Hz) would be more likely to evoke simulator sickness than would conflicting cues at a higher frequency. Actual or potential applications of this work include a preliminary design guidance curve that indicates the frequency range of simulated motion that is likely to evoke simulator or virtual reality sickness; for simulators intended to operate in this frequency range, appropriate simulator sickness interventions should be considered during the design process.
Educational Interventions Successfully Reduce Pedestrians' Overestimates of Their Own Nighttime Visibility
Authors: Tyrrell Richard A. , Patton Chad W. , Brooks Johnell O.
Published: April 2004

Pedestrians dramatically overestimate their own visibility at night. This is likely to result in pedestrians unknowingly engaging in dangerous behavior. To determine the extent to which pedestrians' estimates of their own visibility are influenced by educational interventions, clothing reflectance, and headlamp beam setting, participants in 2 experiments estimated their own nighttime visibility by walking toward a stationary car to the point where they believed they were just recognizable as a pedestrian. In the first experiment 48 university students were tested and in the second experiment 9 high-school driver education students were tested. Overall, participants failed to appreciate the benefits of reflective clothing and of high-beam illumination. However, the participants in Experiment 1 who had heard a relevant lecture several weeks earlier gave estimates that were 10% shorter than did a control group. Participants in Experiment 2 heard a more focused and graphicintensive lecture and gave estimates that were 56% shorter than did a control group. Potential applications of this research include increasing pedestrian safety by designing and implementing research-based public education campaigns aimed at reducing pedestrians' overestimates of their own nighttime visibility.
The Use of Flight Progress Strips While Working Live Traffic: Frequencies, Importance, and Perceived Benefits
Authors: Durso Francis T. , Batsakes Peter J. , Crutchfield Jerry M. , Braden Justin B. , Manning Carol A.
Published: April 2004

The Federal Aviation Administration's effort to automate air traffic control (ATC) requires that the functionality provided today be captured in future systems. We report the first quantitative naturalistic observation of paper flight progress strip interactions during operational use. Strip use was similar in a variety of situations, but some uses varied as a function of altitude, staffing, or the cooperative style used by controller teams. Design of automation should proceed by prioritizing changes based on frequency of use and importance and should ensure that an effective method of interacting with flight information is incorporated. In addition to applied relevance to the ATC domain, the results touch on several theoretical concerns relevant to dynamic environments. Actual and potential applications of this research include the establishment of a database of strip activity and an arsenal of information valuable to system designers.
The Insulin Resistance Syndrome
Authors: Yki-Järvinen Hannele
Published: April 2004

Recognition of the insulin resistance syndrome is clinically important as it predicts both type 2 diabetes and cardiovascular disease. NCEP and WHO have recently published formal definitions that may help identification of the syndrome. Given the large variation of the prevalence and features of the insulin resistance syndrome, the definitions are oversimplifications as they attempt to define a biological continuous phenomenon by fixed numbers, which are unlikely to be equally useful in risk prediction in different ethnic groups. Clinical judgement therefore remains essential in assessing individuals at risk. Such risk assessment obviously also include cardiovascular risk factors such as gender, ethnicity, low‐density lipoprotein cholesterol, smoking, and family history of cardiovascular disease.
Glycated Hemoglobin and Serum Proteins as Tools for Monitoring
Authors: Goldstein Barry J. , Jabbour Serge , Ahmed Intekhab
Published: April 2004

Technological advances have greatly improved our ability to monitor glycemic control in patients with diabetes. To this end, one of the most important clinical advances that has improved modern diabetes care is the recognition that glucose undergoes nonenzymatic chemical reactions with various proteins in the blood, including hemoglobin, in a manner that allows the estimation of an integrated value of the glucose excursions over a period of weeks to months, providing a useful window for glucose monitoring using the hemoglobin A1c(HbA1c). The early 1980s also saw the emergence of a second group of tests, collectively called “fructosamine,” which were based on a determination of glycated serum proteins, especially albumin, and found to be useful for similar clinical purposes over a shorter time period (2–3 weeks) compared to the HbA1c. There has also been growing interest in utilizing measurement of advanced glycosylation end products (AGEs) in serum and in tissues as laboratory correlates of some of the chronic tissue damage observed in patients with diabetes. In the present chapter, starting from a chemical description of the glycation reactions, we will present the pathophysiological background necessary for an understanding of the variety of tests now used for glycated hemoglobin and albumin determination and their interpretation in different clinical encounters. Finally, we will describe AGEs and their potential relationship to the chronic complications of diabetes.
The Microcirculation in Diabetes Mellitus
Authors: Tooke John E.
Published: April 2004

Examination of human microvascular function in the two major forms of diabetes has revealed common abnormalities yet important differences in microvascular behavior. Early microvascular hypertension related to the degree of hyperglycemia appears to be fundamental to the expression of microangiopathy in type 1 diabetes millitus (T1DM), and although plausible biochemical explanations exist for this phenomenon, they remain to be verified in human diabetes. In type 2 diabetes millitus (T2DM) the interplay between preceding insulin resistance, hypertension, and vascular smooth muscle function modifies and confuses the pathophysiological findings, particularly in view of the fact that the emergence of hyperglycemia is difficult to date in this form of the disease. Unraveling of this puzzle may explain the subtle differences in the expression of microangiopathy in T1DM and T2DM, whereas primary manipulation of the hemodynamic and permeability changes may offer real therapeutic potential in the future.
The Diabetic Foot
Authors: Dinh Thanh L. , Veves Aristidis
Published: April 2004

Diabetic foot complications are common manifestations with potentially devastating consequences. Foot pathology encountered in the clinical setting ranges from benign skin and nail changes to the more severe and debilitating ulcerations and infections. Despite adequate therapy, these more serious ulcerations and infections may progress to extensive hospitalizations, lower extremity amputations, and premature death. Over the last decade, considerable strides have been gained in identifying the risk factors and causal pathways leading to diabetic foot problems. Major risk factors for the development of diabetic foot ulcers include peripheral neuropathy, peripheral vascular disease, and high foot pressures. These, along with other predisposing elements in the formation of diabetic foot complications, will be discussed in greater detail later in the chapter. With a greater understanding of the pathogenesis of diabetic foot complications, preventative strategies aimed at limb salvage have been met with greater success.
Gas mixing and modeling of secondary gas distribution in a bench‐scale fluidized bed
Authors: Al‐Sherehy Fahad , Grace John , Adris Alaa‐Eldin
Published: April 2004

The effect of distributing gaseous feed along a bubbling fluidized bed of diameter 152 mm was studied with fluid catalytic cracking particles. Steady‐ and unsteady‐state experiments show that the secondary gas concentration profile at the injection level was almost uniform for high secondary and low primary gas velocities. Secondary gas readily mixed within a short distance above the injection level. Backmixing was primarily influenced by the primary feed superficial gas velocity. Regardless of its injection velocity, secondary gas was barely detectable below the injection level at low primary superficial velocities. Axial dispersion and mass transfer decreased significantly when some gas was introduced at higher levels, compared with a bed where all gas entered through the windbox. Two two‐phase models are proposed to simulate gas mixing, the first with a step‐change in gas flow rate at the injection level, the second accounting for additional mixing in the jet region. © 2004 American Institute of Chemical Engineers AIChE J, 50: 922–936, 2004
Turbulence properties of the impeller stream of a Rushton turbine
Authors: Lee K. C. , Yianneskis M.
Published: April 2004

The structure of the flow in a vessel stirred by a Rushton turbine was investigated using laser Doppler anemometry measurement techniques. The time and length scales of turbulence were determined and used to estimate the dissipation rate of turbulence energy. The levels of turbulence energy and dissipation are high near the turbine and decrease rapidly with increasing distance from the turbine blades. The turbulence in the impeller stream is mostly anisotropic close to the blades. The results are compared with the findings of earlier investigations, and their implications for computational fluid dynamics (CFD) predictions of the flows are discussed.
Block‐oriented NARMAX models with output multiplicities
Authors: Pottmann Martin , Pearson Ronald K.
Published: April 2004

Block‐oriented modeling approaches to the development of NARMAX models for processes exhibiting output multiplicities are introduced. “Feedback block‐oriented” model structures are proposed that can force the resulting NARMAX model to have a particular steady‐state behavior and reduce the model‐identification problem to a constrained, linear model identification. These models are particularly suitable for gray‐box modeling approaches where it is assumed that the steady‐state behavior of the process is known and a NARMAX model is sought to approximate its dynamic response. The proposed approaches are applied to a CSTR model with three steady states to illustrate their peformance.