bluuebunny/crossref_metadata_2025 huggingface dataset:
An Endogenous Circadian Rhythm in Sleep Inertia Results in Greatest Cognitive Impairment upon Awakening during the Biological Night
Authors: Scheer Frank A. J. L. , Shea Thomas J. , Hilton Michael F. , Shea Steven A.
Published: July 2008

Sleep inertia is the impaired cognitive performance immediately upon awakening, which decays over tens of minutes. This phenomenon has relevance to people who need to make important decisions soon after awakening, such as on-call emergency workers. Such awakenings can occur at varied times of day or night, so the objective of the study was to determine whether or not the magnitude of sleep inertia varies according to the phase of the endogenous circadian cycle. Twelve adults (mean, 24 years; 7 men) with no medical disorders other than mild asthma were studied. Following 2 baseline days and nights, subjects underwent a forced desynchrony protocol composed of seven 28-h sleep/wake cycles, while maintaining a sleep/wakefulness ratio of 1:2 throughout. Subjects were awakened by a standardized auditory stimulus 3 times each sleep period for sleep inertia assessments. The magnitude of sleep inertia was quantified as the change in cognitive performance (number of correct additions in a 2-min serial addition test) across the first 20 min of wakefulness. Circadian phase was estimated from core body temperature (fitted temperature minimum assigned 0°). Data were segregated according to: (1) circadian phase (60° bins); (2) sleep stage; and (3) 3rd of the night after which awakenings occurred (i.e., tertiary 1, 2, or 3). To control for any effect of sleep stage, the circadian rhythm of sleep inertia was initially assessed following awakenings from Stage 2 (62% of awakening occurred from this stage; n = 110). This revealed a significant circadian rhythm in the sleep inertia of cognitive performance ( p = 0.007), which was 3.6 times larger during the biological night (circadian bin 300°, ~2300—0300 h in these subjects) than during the biological day (bin 180°, ~1500—1900 h). The circadian rhythm in sleep inertia was still present when awakenings from all sleep stages were included ( p = 0.004), and this rhythm could not be explained by changes in underlying sleep drive prior to awakening (changes in sleep efficiency across circadian phase or across the tertiaries), or by the proportion of the varied sleep stages prior to awakenings. This robust endogenous circadian rhythm in sleep inertia may have important implications for people who need to be alert soon after awakening.
Spatial and Circadian Regulation of cry in Drosophila
Authors: Hao Zheng  , Ng Fanny , Yixiao Liu  , Hardin Paul E.
Published: July 2008

In Drosophila, cryptochrome ( cry) encodes a blue-light photoreceptor that mediates light input to circadian oscillators and sustains oscillator function in peripheral tissues. The levels of cry mRNA cycle with a peak at ~ZT5, which is similar to the phase of Clock ( Clk) mRNA cycling in Drosophila. To understand how cry spatial and circadian expression is regulated, a series of cry-Gal4 trans-genes containing different portions of cry upstream and intron 1 sequences were tested for spatial and circadian expression. In fly heads, cry upstream sequences drive constitutive expression in brain oscillator neurons, a novel group of nonoscillator cells in the optic lobe, and peripheral oscillator cells in eyes and antennae. In contrast, cry intron 1 drives rhythmic expression in eyes and antennae, but not brain oscillator neurons. These results demonstrate that intron 1 is sufficient for high-amplitude cry mRNA cycling, show that cry upstream sequences are sufficient for expression in brain oscillator neurons, and suggest that cry spatial and circadian expression are regulated by different elements.
Taxonomic composition of the Holocene forests of the northern coast of Spain, as determined from their macroremains
Authors: Garcia-Amorena I. , Morla C. , Rubiales J.M. , Gomez Manzaneque F.
Published: July 2008

Eight sites distributed over a distance of some 400 km of the Cantabrian coast (northern Spain) provided 153 wood, 50 fruit and over 350 leaf remains belonging to the area's Holocene forests. The high taxonomic precision with which these macroremains were identified (in many cases at the species level), plus the accurate information available regarding the original growth locations of these plants, provide new geobotanical insights into the history of northern Spain's Atlantic forests. Radiocarbon dating of the wood samples showed the collected material to have lived between 8550 and 800 cal. BP. Analysis of the macroremains showed the deciduous mixed forests of the Holocene to contain a majority of Quercus robur and Corylus avellana, accompanied by Acer pseudoplatanus, Ulmus minor, Castanea sp., and hygro-thermophilous taxa (Arbutus, Laurus and Vitis vinifera). The remains of hygrophilous communities, dominated by Salix atrocinerea, Alnus glutinosa and Fraxinus sp., show these to have expanded during the Holocene. The absence of conifer macroremains is interpreted as reflecting the disappearance of Würmian conifer populations at the beginning of the Holocene. The different taxa (eg, Ilex spp. and V. vinifera) that survived the last glaciation in the refugia offered by Spain's northern coast persisted in the same areas during the Holocene. A leaf sample of Ulmus minor dating to 3950 ±120 cal. BP reveals for the first time the natural occurrence of this species on the northern coast of Spain.
Postglacial evolution and spatial differentiation of seasonal temperate rainforest in western Canada
Authors: Brown K.J. , Nielsen A.B. , Fitton R.J. , Hebda R.J.
Published: July 2008

Surface samples from Vancouver Island, Canada, were used to assess the relationship between discrete seasonal temperate rainforest (STR) plant communities and their corresponding pollen signatures. Pollen from ten sediment cores was further used to evaluate the postglacial development of these communities. Principal components analysis (PCA) of the surface data revealed the distinctiveness of the modern pollen rain, with samples from the Coastal Douglas Fir (CDF) zone, the dry Coastal Western Hemlock (CWH) zone, the wet CWH subzones and the Mountain Hemlock (MH) zone clustering distinctly. PCA of the fossil data revealed early-seral open canopy, wet rainforest, subalpine rainforest and Lateglacial plant associations and showed that the STR has changed markedly through time. Pinus woodlands with low palynological richness prevailed in the early Lateglacial period, only to be supplanted by mixed conifer forest with increased pollen richness. In the early Holocene, STR vegetation differentiated spatially as early-seral open canopy forests expanded, though a non-analogue Picea-dominated forest persisted on the moist outer coast. Generally high pollen richness is attributed to the expansion of dryland habitat coupled with the development of a fire-maintained vegetation mosaic. In the mid- and late-Holocene intervals, open canopy communities persisted in eastern areas, eventually developing into modern CDF and dry CWH forest. In contrast, moist and oceanic CWH rainforest developed on central and western Vancouver Island, whereas subalpine forest established at high elevation. Pollen richness declined in the mid Holocene concomitant with increased precipitation and a general reduction in the incidence of fire, though this trend was offset somewhat in the late Holocene by paludification.
Variability of subsurface denitrification and surface productivity in the coastal eastern Arabian Sea over the past seven centuries
Authors: Agnihotri Rajesh , Kurian Siby , Fernandes Michelle , Reshma K. , D'Souza W. , Naqvi S.W.A.
Published: July 2008

Temporal variations over the last ~700 years in surface productivity and subsurface denitrification in the coastal eastern Arabian Sea (off Goa), a hydrographically unique environment that experiences seasonal near-bottom anoxia, have been investigated using multiple geochemical and isotopic proxies. The results suggest that surface productivity was much lower than it is today during all major solar minima during this period, but subsurface denitrification appears to have weakened substantially only during ~AD 1650 to 1750, within the period of the `Little Ice Age' (LIA; from ~AD 1500 to 1750), most probably a result of a less vigorous upwelling associated with a decreased southwest monsoon strength. The proxy data indicate that the productivity during the last ~150 years (the Anthropocene) has been higher than ever before in the past 700 years, and water column measurements demonstrate that the region currently experiences extremely intense denitrification; yet, the nitrogen isotopic ratio in sedimentary organic matter (δ15N) exhibits a moderately declining trend during this period. This is ascribed to dilution by terrestrial sources and/or to small isotopic effect associated with vigorous denitrification that removes all nitrate, with possibly additional inputs of light nitrogen through fixation by the diazotrophs that is probably tightly coupled to denitrification. Thus, our results reveal limitation of sedimentary δ 15N as a proxy for palaeodenitrification despite excellent preservation of organic matter in coastal sediments.
The Mt Logan Holocene—late Wisconsinan isotope record: tropical Pacific—Yukon connections
Authors: Fisher David , Osterberg Erich , Dyke Art , Dahl-Jensen Dorthe , Demuth Mike , Zdanowicz Christian , Bourgeois Jocelyne , Koerner Roy M. , Mayewski Paul , Wake Cameron , Kreutz Karl , Steig Eric , Zheng James , Yalcin Kaplan , Goto-Azuma Kumiko , Luckman Brian , Rupper Summer
Published: July 2008

The ice core recovered from Prospector Russell Col on Mt Logan (5.4 km a.s.l.), in the Yukon spans over 20 000 years. This unique record offers a Pacific view of the stable isotope and chemical record from the Lateglacial to the present. The timescale is based on seasonal counted years, the largest known volcanic acid signatures and the major shift in stable isotopes and chemistry at the end of the Younger Dryas. There are large and sustained changes in the stable isotopic record that are anti-correlated with marine and continental chemistry series. The oxygen-18 in this area is not a proxy for palaeotemperature but rather for source region. The last major isotope shift in AD 1840 in δ(18O) and chemistry is compared with the Quinn's ENSO record. During periods of more frequent La Niña (stronger tropical easterlies) there is more zonal flow of water vapour transport to the Pacific Northwest, δ(18O) values are larger and the deuterium excess d smaller. These periods coincide with periods of lower accumulation/precipitation in southern Yukon. The Holocene δ(18O) record indicates many large shifts between the meridional (strong El Niño) and zonal (La Niña). Comparison of the Logan isotopic record and the moisture/temperature-sensitive time series of peat bog inception dates for the Northwest shows a strong correlation (0.36) that points to high accumulation rates coincident with low δ(18O) and enhanced meridional flow. Major changes in the core at 4200 BP and 7000—8000 BP point to enhanced meridional flow, which coincide with big changes in the Pacific palaeorecords of the balance between El Niño and La Niña. 4200 BP seems to have inaugurated the `modern' ENSO world.
Responses to light and radiation: a guide to units, conversion factors and computations
Authors: Preston J.S.
Published: July 2008

The paper gives explicit instruction on numerical procedures applicable in photometry and radiometry, for example in deriving the spectral power distribution of a source from spectrophotometric comparison with an existing standard, the luminous efficacy of a radiation, responses of detectors including the 'photometric eye', and in the various conversions of such responses from one basis to another. With an introduction on the relation between photometry and radiometry, particularly as regards units, and with mention of the special problems of biological and photographic responses, it is intended as a practical guide for those whose work overlaps these various fields or who may be unfamiliar with the basic radiometric concepts. It includes a table of values of K(x) and of the luminous efficacy of black-body radiations over the range 1800 to 3400 K.
Computerized Simulation in the Social Sciences
Authors: Garson G. David
Published: July 2008

After years at the periphery of the social sciences, simulation is now emerging as an important and widely used tool for understanding social phenomena. Through simulation, researchers can identify causal effects, specify critical parameter estimates, and clarify the state of the art with respect to what is understood about how processes evolve over time. Moreover, simulation methods are often the most time-effective and cost-effective means of doing so and sometimes are the only means. This essay outlines current developments in the four main branches of social science simulation: systems dynamics models, network models (including neural network models), spatial models, and agent-based models. The limitations of simulation modeling are also discussed, along with methods for evaluating the validity of social science computer simulations.
Computerization in the Strategic Management Course: Current Status and Future Directions
Authors: Morris Rebecca J. , Johnson Bradley R.
Published: July 2008

This article presents the findings of a survey of strategic management professors on the current status of computerization in strategic management courses. Through an analysis of the reported advantages or disadvantages of current tools, a conceptual model is developed that depicts key dimensions for optimal design of future instructional software. The authors conclude by describing ways in which pedagogical research can help focus the software development process on the techniques that hold the most promise for superior educational value.
Emotional and Behavioral Problems Reported in Child Welfare Over 3 Years
Authors: McCrae Julie S.
Published: July 2008

Child welfare agencies are required to provide services that ensure that children receive adequate mental health care. This study provides a comprehensive view of the emotional and behavioral problems of children who are referred to child welfare services, using nationally representative data. Bivariate analyses compare rates by child demographics, and conditional probability tables present changes in clinical status. Results show that 62% of children have at least one clinical-level score over 3 years. Rates are highest at baseline. Posttraumatic stress most frequently improves, whereas thought, attention, and aggressive/ delinquent behavior problems are most persistent. Sexualized behavior is more common among White and Hispanic children, and boys are reported with more internalizing problems than do girls. Targeted services are needed for young children who experience posttraumatic stress, as is treatment for attention problems that accounts for both biological and environmental components. Distinguishing the effects of age, environment, and assessment methods on boys' internalizing problems is also critical.
Understanding School Personnel's Resistance to Adopting Schoolwide Positive Behavior Support at a Universal Level of Intervention
Authors: Lohrmann Sharon , Forman Susan , Martin Stacy , Palmieri Mark
Published: July 2008

In recent years, a large number of schools around the country have implemented schoolwide positive behavior support (SWPBS; Sugai & Horner, 2006). Because of the increasing use of this model of support, research examining the factors associated with implementation is needed. The purpose of this investigation was to document and contextualize technical assistance providers' observations and perspectives about what factors influenced or explained school personnel's resistance toward implementing the universal level of SWPBS. Qualitative research methods were used to investigate the barrier conditions considered by technical assistance providers as influential on school personnel's resistance to adopting SWPBS at a universal level of intervention and the complementary strategies used to promote cooperation and commitment. Multiple interviews from 14 technical assistance providers suggest five barrier conditions that contribute to resistance and the complementary strategies used to promote cooperation and commitment. A detailed description of the five conditions and strategies is provided. Additionally, implications for practice and areas of future research are addressed.
Identification of FcγRIIa as the ITAM-bearing receptor mediating αIIbβ3 outside-in integrin signaling in human platelets
Authors: Boylan Brian , Gao Cunji , Rathore Vipul , Gill Joan C. , Newman Debra K. , Newman Peter J.
Published: July 2008

Immunoreceptor tyrosine-based activation motif (ITAM)–containing proteins have recently been demonstrated in macrophages and neutrophils to be required for cell surface integrins to transmit activation signals into the cell. To identify ITAM-bearing proteins that mediate signaling via the platelet-specific integrin αIIbβ3, fibrinogen binding was induced by (1) allowing platelets to spread directly on immobilized fibrinogen, or (2) activating the PAR1 thrombin receptor on platelets in suspension. Both initiated strong, ligand binding–dependent tyrosine phosphorylation of the ITAM-bearing platelet Fc receptor, FcγRIIa, as well as downstream phosphorylation of the protein tyrosine kinase Syk and activation of phospholipase Cγ2 (PLCγ2). Addition of Fab fragments of an FcγRIIa-specific monoclonal antibody strongly inhibited platelet spreading on immobilized fibrinogen, as well as downstream tyrosine phosphorylation of FcγRIIa, Syk, and PLCγ2, and platelets from a patient whose platelets express reduced levels of FcγRIIa exhibited markedly reduced spreading on immobilized fibrinogen. Finally, fibrinogen binding–induced FcγRIIa phosphorylation did not occur in human platelets expressing a truncated β3 cytoplasmic domain. Taken together, these data suggest that ligand binding to platelet αIIbβ3 induces integrin cytoplasmic domain–dependent phosphorylation of FcγRIIa, which then enlists selected components of the immunoreceptor signaling cascade to transmit amplification signals into the cell.
Enzymatic, immunological and phylogenetic characterization of Brucella suis urease
Authors: Contreras-Rodriguez Araceli , Quiroz-Limon Jose , Martins Ana M , Peralta Humberto , Avila-Calderon Eric , Sriranganathan Nammalwar , Boyle Stephen M , Lopez-Merino Ahide
Published: July 2008

Background

The sequenced genomes of the Brucella spp. have two urease operons, ure-1 and ure-2, but there is evidence that only one is responsible for encoding an active urease. The present work describes the purification and the enzymatic and phylogenomic characterization of urease from Brucella suis strain 1330. Additionally, the urease reactivity of sera from patients diagnosed with brucellosis was examined.

Results

Urease encoded by the ure-1 operon of Brucella suis strain 1330 was purified to homogeneity using ion exchange and hydrophobic interaction chromatographies. The urease was purified 51-fold with a recovery of 12% of the enzyme activity and 0.24% of the total protein. The enzyme had an isoelectric point of 5, and showed optimal activity at pH 7.0 and 28–35°C. The purified enzyme exhibited a Michaelis-Menten saturation kinetics with a K

m
of 5.60 ± 0.69 mM. Hydroxyurea and thiourea are competitive inhibitors of the enzyme with Ki of 1.04 ± 0.31 mM and 26.12 ± 2.30 mM, respectively. Acetohydroxamic acid also inhibits the enzyme in a competitive way. The molecular weight estimated for the native enzyme was between 130–135 kDa by gel filtration chromatography and 157 ± 7 kDa using 5–10% polyacrylamide gradient non-denaturing gel. Only three subunits in SDS-PAGE were identified: two small subunits of 14,000 Da and 15,500 Da, and a major subunit of 66,000 Da. The amino terminal sequence of the purified large subunit corresponded to the predicted amino acid sequence encoded by ureC1. The UreC1 subunit was recognized by sera from patients with acute and chronic brucellosis. By phylogenetic and cluster structure analyses, ureC1 was related to the ureC typically present in the Rhizobiales; in contrast, the ureC2 encoded in the ure-2 operon is more related to distant species.

Conclusion

We have for the first time purified and characterized an active urease from B. suis. The enzyme was characterized at the kinetic, immunological and phylogenetic levels. Our results confirm that the active urease of B. suis is a product of ure-1 operon.
A Novel Genetic Algorithm Based on Gene Therapy Theory
Authors: Wang Chao-Xue , Cui Du-Wu , Wan Ding-Sheng , Wang Lei
Published: July 2008

Based on the analyses of a genetic algorithm’s properties and shortages, a novel genetic algorithm (GTGA) is proposed with analogies to the concept and method of gene therapy theory. The core of GTGA lies on construction of a gene pool and a therapy operator. The gene pool, which is first created according to prior knowledge and then is updated according to posterior knowledge, contains eminent genes, morbid genes and their character istic information as well. The therapy operator consists of an insertion operation that inserts eminent genes into an individual and a removing operation that removes morbid genes from an individual. The methods of creation and updating of the gene pool and contruction of the therapy operator are given and demonstrated by the travelling salesman problem (TSP). To validate the superiority of the GTGA, a conventional genetic algorithm (GA), a novel genetic algorithm based on immunity (IGA) and the GTGA are compared as regards TSP. The simulation results show that the GTGA can restrain the premature convergence phenomenon effectively during the evolutionary process while greatly increasing the convergence speed.
A Fault Diagnosis Method for Transformer Integrating Rough Set with Fuzzy Rules
Authors: Wang Zhiyong , Guo Chuangxin , Jiang Quanyuan , Cao Yijia
Published: July 2008

Although the International Electrotechnical Commission (IEC) codes method has been widely used to interpret dissolved gas-in-oil analysis (DGA) results in the world, it sometimes fails to diagnose, especially when more than one fault exists in a transformer. This paper presents a rough set-based fuzzy logic technique, which can diagnose multiple faults in a transformer. By applying rough set theory to the IEC codes, the reduct of the decision table can be obtained. By using a fuzzy method, the fuzzy membership functions of each fault diagnosis decision rules are displayed, and finally the fault type of the transformer is diagnosed. The application of this method to some transformers has yielded promising results.
Estimation of Crowd Density Based on Wavelet and Support Vector Machine
Authors: Xiaohua Li , Lansun Shen , Huanqin Li
Published: July 2008

Automatic estimation of crowd density is very important for the safety management of the crowds. In particular, when the density of the crowds exceeds a critical level, the safety of people in the crowd may be compromised. This paper describes a novel method to estimate the crowd density based on the combination of multi-scale analysis and a support vector machine. The algorithm will first transform the crowd image into multi-scale formats using wavelet transform. The first-order and second-order statistical features at each scale of the transformed images are then extracted as density character vectors. Furthermore, a classifier based on a support vector machine is designed to classify the extracted density character vectors into different density levels. Compared with the conventional statistical techniques and wavelet energy techniques used in single-scale images, the test results of a set of 300 images show that the proposed algorithm can achieve much improved performance and more detailed information of the crowd density can be captured by the new feature extraction method.
Change in the iso-enzyme profiles of urinary N-acetyl-b-D-glucosoaminidase in workers exposed to mercury
Authors: Mandic Ljuba , Radmila Maksimovic , Jelena Acimovic , Dubravka Dobric
Published: July 2008

The iso-enzyme profiles of urinary N-acetyl-b-D-glucosoaminidase (NAG) were studied in the workers from a chloro-alkaline electrolysis plant that had been continuously exposed to elemental mercury. The same workers then had a work break of four months and were later re-exposed to mercury for another five months. The activities of urinary NAG in workers exposed to mercury before and after the work break and in the control group were 2.099 / 1.03 IU/L; 0.909 / 0.52 IU/L and 1.139 / 0.35 IU/L, respectively. The fraction of the dominant A form activity in the total activity, in the workers exposed to mercury after a work break (85.319 / 5.32%), was almost equal to the fraction of A in the control group (84.649 / 2.75%). The percent fraction of A forms (A and A2) during continuous exposure was almost equal to the sum of the fractions A and A2 in the control group and for exposure after the work break. The fraction of the B form activity in the total activity during exposure to elemental mercury for five months after the work break (7.419 / 3.45%) was lower (P B / 0.1) than the fraction of the B form in the control group (8.629 / 2.19%). The decrease in the fraction of the B form compared with the control group was more significant (P B / 0.001) in the case of continuously exposed workers (5.259 / 2.55%). Beside the major A and B iso-enzymes of NAG, the A2form was also isolated, and its fraction in the control group (6.739 / 2.15%) was not negligible. For workers exposed to mercury for five months, it was 7.289 / 3.52%. It is concluded that mercury affected the increased exocytosis of iso-enzyme A and the inhibition of B iso-enzyme of NAG. The increase in activity of urinary NAG in subjects exposed to mercury was a consequence of the increased excretion of A form. It was established also that the four months work break was sufficient for the repair of renal damages that occurred during continuous exposure, and which were monitored by the activity of NAG. Thus, the effects of mercury seem to have been reversible.
The dermal toxicity of cement
Authors: Winder Chris , Carmody Martin
Published: July 2008

Cement and concrete are products used widely in the construction sector, with a traditional perception that any hazards that they have are limited to dermatitis in a small number of workers. In some cases, employers and builders do not think that concrete is a chemical. However, contact dermatitis is one of the most frequently reported health problems among construction workers. A review of the available literature suggests that cement has constituents that produce both irritant contact dermatitis and corrosive effects (from alkaline ingredients such as lime) and sensitization, leading to allergic contact dermatitis (from ingredients such as chromium). These findings indicate that cement and concrete should be treated as hazardous materials, and that workers handling such products should reduce exposure wherever possible. Initiatives to reduce the chromium content of cement have been shown to be successful in reducing the incidence of allergic dermatitis, although the irritant form remains.
Mutagenic effects of cutting fluids and components in the Salmonella typhimurium mutagenicity assay
Authors: Kleber Marcus , Blaszkewicz Meinolf , Lucas Stephanie , Bolt Hermann M , Föllmann Wolfram
Published: July 2008

Emulsions of water-soluble cutting fluids (wsCF) are used in large quantities in the metal industry. In order to reduce the costs for use and disposal of these fluids, new technologies are being introduced. Minimist Lubricant Supply (MLS) uses only minimal amounts of cutting fluids. In contrast to conventional wsCF, which are complex multicompound mixtures, MLS cutting fluids are composed of one or two components only, like fatty alcohols and fatty acid esters. The aim of the study was to identify and compare the mutagenic potential of these cutting fluids as a first indicator of a possible hazard of systemic effects after inhalation or dermal absorption of the fluids at the workplace.

The Salmonella typhimurium assay (Ames assay) was used as a screening method to detect mutagenic effects of cutting fluids. Conventional wsCF and MLS cutting fluids were tested in the strains TA 98, TA 100, TA 102 and TA 104, in the presence and absence of an external metabolizing enzyme system (rat liver S9-mix), using a preincubation (20 min) test protocol.

For MLS fluids, no mutagenicity was found in a concentration range between 1 and 10 mg/plate in the Ames assay. Among five tested conventional wsCF, two were mutagenic in the Ames assay at concentration ranges between 2.5 and 15 mg/plate. In cooperation with the manufacturer, 18 defined components of cutting fluids were tested separately. The results revealed that formaldehyde generators, derivatives of oxazolidine and hexahydrotriazine used as biocides for preservation of the fluids, were mutagenic. Four components were nonmutagenic but cytotoxic, whereas the remaining components displayed no bacterial mutagenicity.

The present results show the potential hazard of biocides for workers handling these fluids. An exposure via inhalation and/or dermal absorption could cause an additional risk due to mutagenic ingredients. Under aspects of workers’ safety, a further discussion about the use of specific components in cutting fluids is recommended.
Fitting competing risks with an assumed copula
Authors: Escarela Gabriel , Carriere Jacques F.
Published: July 2008

We propose a fully parametric model for the analysis of competing risks data where the types of failure may not be independent. We show how the dependence between the cause-specific survival times can be modelled with a copula function. Features include: identifiability of the problem; accessible understanding of the dependence structures; and flexibility in choosing marginal survival functions. The model is constructed in such a way that it allows us to adjust for concomitant variables and for a dependence parameter to assess the effects of these on each marginal survival model and on the relationship between the causes of death. The methods are applied to a prostate cancer data set. We find that, with the copula model, more accurate inferences are obtained than with the use of a simpler model such as the independent competing risks approach.
Deviations from the population-averaged versus cluster-specific relationship for clustered binary data
Authors: Have Thomas R Ten , Ratcliffe Sarah J , Reboussin Beth A , Miller Michael E
Published: July 2008

There has been much debate about the relative merits of mixed effects and population-averaged logistic models. We present a different perspective on this issue by noting that the investigation of the relationship between these models for a given dataset offers a type of sensitivity analysis that may reveal problems with assumptions of the mixed effects and/or population-averaged models for clustered binary response data in general and longitudinal binary outcomes in particular. We present several datasets in which the following violations of assumptions are associated with departures from the expected theoretical relationship between these two models: 1) negative intra-cluster correlations; 2) confounding of the response-covariate relationship by cluster effects; and 3) confounding of autoregressive relationships by the link between baseline outcomes and subject effects. Under each of these conditions, the expected theoretical attenuation of the population-averaged odds ratio relative to the cluster-specific odds ratio does not necessarily occur. In all cases, the naive fltting of a random intercept logistic model appears to lead to bias. In response, the random intercept model is modified to accommodate negative intra-cluster correlations, confounding due to clusters, or baseline correlations with random effects. Comparisons are made with GEE estimation of population-averaged models and conditional likelihood estimation of cluster-specific models. Several examples, including a cross-over trial, a multicentre nonrandomized treatment study, and a longitudinal observational study are used to illustrate these modiflcations.
Brain death
Authors: Elliot JM
Published: July 2008

Since the Harvard report of 1968, the concept of brain death has become widely recognized throughout the world. Most developed countries have accepted brain death as constituting death of the individual, and allow such patients to be used as ‘heart-beating’ organ donors. Although the US and most other countries accept a ‘whole-brain’ definition of brain death, the concept of brainstem death has been adopted in the UK. This article describes the UK diagnostic criteria in detail, and compares these with the criteria used in other countries. Management of the brain dead organ donor is described, and controversies relating to the concept of brain death are also discussed.
Synthesis of specular reflectors for a finite size light source
Authors: Korobko AA , Kush OK
Published: July 2008

Finding a reflector shape to provide a required light distribution is a major problem in the design of luminaires. Most methods for solving the problem assume the light source is a point. However, this assumption leads to great discrepancies between the required and calculated luminous intensity. In addition, it gives no answer to the question of whether it is possible to provide any arbitrary light distribution. A method for computing the shape of a specular reflector, with cylindrical or axial symmetry, operating with a finite size light source and providing a required light distribution, is presented in this study. The luminance distribution of the surface of the light source is specified very close to reality. The method is based on solving a system of first-order differential equations that describe a pro-file curve of a reflector under specified initial conditions (Cauchy problem). The study defines under what conditions a required light distribution of a reflector can be realized. The mechanism (image transformation function) for finding the optimum geometrical parameters of a reflector for a given light distribution and for given initial conditions is described.
Variation of the luminous efficacy of direct, global and diffuse solar radiation with atmospheric parameters
Authors: Pons A , Barrio A , Campos J
Published: July 2008

A detailed study is presented of the relationship between the luminous efficacy of the three components of solar radiation (direct, global and diffuse) for a cloudless sky, and solar zenith angle, ozone content, water vapour content and turbidity. Aerosols and water vapour are found to be the most important factors. Other factors such as ozone or the aerosol downward scattered fraction are generally of secondary importance. Calculated luminous efficacies are based on a simple transmittance parameterization of the spectral irradiance model.
Reflectance distributions and vertical daylight illuminances in atria
Authors: Sharples S , Lash D
Published: July 2008

In this study parametric changes were made to the distribution of the reflectances of diffuse vertical surfaces in the wells of model square atria placed in an artificial sky. The effects of these changes on the vertical daylight levels at various heights for central positions were examined. Painting the atrium surfaces with alternating, equal width bands of white and black matt paint created the reflectance distribution variability. The widths of the bands were gradually reduced, although the 50:50 black to white ratio was kept constant. The different distributions of reflectances were found to have very little effect on vertical daylight factor and internally reflected component values low down in the atrium well. For some of the higher measurement locations large differences were observed between the different reflectance distributions. Generally, as the bands became narrower and more numerous the daylight levels converged towards values that would be predicted from standard formulae using the area-weighted reflectance of the atrium.
Bent Donor Molecules and Their Charge-transfer Salts with Magnetic FeIII and CuII Ions
Authors: Sugimoto Toyonari
Published: July 2008

New donor molecules with a bent molecular skeleton, tetrathiafulvalenoquinone(-thioquinone)-1,3-dithiole(-diselenole)methides are synthesized, which are used for the preparation of charge-transfer (CT) salts with magnetic FeIII and CuII ions. The CT salts with FeX4− (X = Cl and Br) ions have such crystal structures that are composed of alternating layers of the donor molecules and the FeX4− ions. On the other hand, for the CT salts with CuII ions the donor molecules or both the donor molecules and the CuII ions are stacked to each other to form one-dimensional channels, where the other CuI and/or CuII ions are included inside. Depending on the stacking structures of the donor molecules electrical conducting properties are metallic, semiconducting or insulating. The d spins of the FeIII and CuII ions interact by themselves and also with the conducting π electrons of the donor molecules, bringing about ferromagnetic, weak ferromagnetic, or antiferromagnetic orderings.
Synthesis and Characterization of Doped Rare Earth Oxides for Environmentally Benign Nontoxic Reddish-yellow Pigments
Authors: Sreeram Kalarical Janardhanan , Aby Chervathoor Poulose , Nair Balachandran Unni
Published: July 2008

Ce10PrxWyOz, where x and y varied from 0.075 to 0.6 solid solutions of oxides of Ce, Pr, and W have been synthesized by solid-state route with a goal of employing them as environmentally friendly reddish-yellow colorants. Pigments were highly crystalline, chemically stable and could be employed for surface coating.
A New Method for the Generation of Indole-2,3-quinodimethanes from Allenamides
Authors: Fuwa Haruhiko , Tako Tomomi , Ebine Makoto , Sasaki Makoto
Published: July 2008

A new method for the generation of indole-2,3-quinodimethanes based on a palladium-catalyzed cascade process starting from N-(o-iodophenyl)allenamides has been developed.
Redox Gradations in Ruthenium Porphycene Complexes and the Porphyrin Analogs: Axial and Macrocyclic Ligand Effects
Authors: Okawara Toru , Abe Masaaki , Shimakoshi Hisashi , Hisaeda Yoshio
Published: July 2008

This paper reports synthesis and electrochemistry of six-coordinate ruthenium porphyrin isomers including six novel porphycene complexes with substituted pyridines in the axial positions, in which redox potential control of reversible RuII/RuIII processes is successfully achieved over a 0.7-V potential region by varying the axial ligands and tetrapyrrole ligand structure and substituents.
Reliability of self-collected versus provider-collected vaginal swabs for the diagnosis of bacterial vaginosis
Authors: Kashyap Bineeta , Singh Ruchira , Bhalla Preena , Arora Raksha , Aggarwal Abha
Published: July 2008

Women reluctant to undergo a per-speculum examination consider self-sampling more acceptable. The aim of this study was to compare self-collected vaginal swabs for detection of bacterial vaginosis (BV), candidiasis and trichomoniasis, with vaginal specimens obtained by the gynaecologist at per-speculum examination. Self-collected and provider-collected vaginal swabs were obtained from 50 women attending the gynaecological outpatients department. The Gram-stained smears and saline wet mounts prepared from the provider-collected vaginal swabs were examined by a microbiologist and a gynaecologist. We determined the validity and the inter-rater reliability of the overall BV score and the morphotype specific score using Kappa statistics. When compared with the provider-collected smear, the ability of the self-collected smear to diagnose BV had a sensitivity of 70% and a specificity of 97%. With specific instructions to help assure the depth of sampling, self-collected swabs can reasonably approximate specimens obtained by clinicians during speculum examination for the diagnosis of BV.
Time to virological failure with atazanavir/ritonavir and lopinavir/ritonavir, with or without an H2-receptor blocker, not significantly different in HIV observational database study
Authors: Keiser Philip H , Nassar Naiel
Published: July 2008

A retrospective electronic database study was conducted to determine any differences in time to virological failure and percent of virological failure among HIV-infected patients concurrently receiving H2-blockers versus patients not receiving these agents while receiving atazanavir (ATV)/ritonavir (r) or lopinavir (LPV)/r-containing antiretroviral treatment regimens. Data were culled from October 2003 (when ATV became commercially available) through February 2006. Virological failure was defined as (1) two plasma HIV-1 RNA levels >400 copies/mL after at least one HIV-1 RNA level below the level of detection or (2) failure to achieve an HIV-1 RNA <400 copies/mL within 24 weeks. Data from 267 ATV/r-treated patients who met the case definition were compared with data from 670 LPV/r-treated patients. Approximately 10% of the ATV/r group received concurrent H2-blockers when compared with 20% of the LPV/r group. Multivariate analysis showed no statistically significant differences regarding time to virological failure between or among the four subgroups, adjusting for differences in baseline characteristics ( P = 0.79, log-rank test). At 750 days following treatment initiation, the proportion of patients not experiencing virological failure was 56% in the ATV/r-blocker subgroup, 48% in the ATV/r-alone subgroup, 45% in the LPV/r-alone subgroup and 42% in the LPV/r-blocker subgroup.
Referral of young people attending a sexual assault referral centre to mental health services
Authors: Sacks R J , Cybulska B A , Forster G E
Published: July 2008

Mental health issues following sexual assault in young people are common but early intervention may improve outcome. A retrospective case-note review of 58 female patients aged between 13 and 18 attending The Haven Whitechapel, a sexual assault referral centre, demonstrated past emotional problems in 72% of those seen, and current emotional problems in 95% of those being followed up. Fifteen percent were already involved with adolescent mental health services (AMHS). All patients requiring and not already receiving input were referred to AMHS or in-house. Of 23 patients referred to AMHS, eight (35%) were accepted and the patients attended, seven (30%) were accepted but did not attend, six (26%) were declined and the outcome of two referrals was unknown. The prevalence of emotional problems and inconsistent referral outcomes demonstrate a need for closer links with AMHS, clearer referral criteria and improved referral pathways.
Acceptability of chlamydia screening using self-taken vaginal swabs
Authors: Doshi J S , Power J , Allen E
Published: July 2008

In the first phase of the National Chlamydia Screening Programme (NCSP), the majority of sites involved offered testing with urine sample. Camden & Islington (C&l) were the first site to offer testing with self-taken vaginal swabs (SVS). SVS are appropriate specimens for diagnosing chlamydia by nucleic acid amplification tests. This study aimed to assess the uptake and acceptability of chlamydia screening using SVS within C&l contraceptive clinics. Data collected from women participating in the NCSP between June 2003 and April 2004 were analysed. Of the 3936 women who accepted screening, 90.4% provided a SVS and only 5.8% accepted the offer of providing a urine sample as an alternative to SVS. Women over 19 years and women from Asian ethnic groups were most likely to decline any screening. No woman stated a reluctance to provide a SVS as a reason for declining screening, confirming the acceptability of SVS for chlamydia screening.
Reinterpreting the Homeric Simile of Iliad 16.7–11: The Girl and Her Mother In Ancient Greek Warfare
Authors: Gaca Kathy L.
Published: July 2008

Though long regarded as a scene of mother-daughter domesticity during peacetime, Iliad 16.7–11 reveals the destruction of normal life for a daughter and her mother on the verge of being captured by ancient Greek warriors. As such it provides exemplary insight into this fundamental aspect of ancient warfare. Further, as reinterpreted here, the simile gains great dramatic and emotive power, strengthens the Homeric characterization of Achilles as a forthright speaker given to poetic realism, and heightens the tragedy of Patroclus by revealing how Achilles by his own admission fails to fulfill his protective role as Patroclus' warrior mother.
Aeschylus, Euripides, and Tragic Painting: Two Scenes from Agamemnon and Hecuba
Authors: O'Sullivan Patrick
Published: July 2008

Aeschylus' famous simile comparing Iphigeneia to a painting just before her sacrifice ( Ag . 239–42) rests not just on the girl's silence and unbroken gaze at her killers but also on the strikingly pitiable nature of her expression. The Euripidean Hecuba's plea to Agamemnon to pity her by gazing on her "like a painter" ( Hec . 807–8) develops this idea and comprises a parallel to aspects of ancient literary criticism that prescribe an emotive identity between poets and their works. The incorporation of painting into these highly charged moments focuses on its ability to arouse pity, a preeminent emotion of tragedy overall.
Ut Sculptura Poesis : Statius, Martial, and the Hercules Epitrapezios of Novius Vindex
Authors: McNelis Charles
Published: July 2008

Statius' Silvae 4.6 and Martial's Epigrams 9.43 and 9.44 concern a Greek statue that, after a storied history, has ended up in the hands of Novius Vindex, an otherwise obscure Roman of the early imperial period. While Vindex manifestly fits into the pattern of Romans who use Greek art to enhance their position and status, the two poets also use the statue to demonstrate their inheritance and control of the work of generic predecessors in order to underscore their own poetic accomplishments in an imperial Roman world.
Octavian and Egyptian Cults: Redrawing the Boundaries of Romanness
Authors: Orlin Eric M.
Published: July 2008

Octavian's decision in 28 B.C.E. to ban Egyptian cults from within the pomerium was not a sign of hostility to foreign cults, especially since the emperor himself arranged for the restoration of those shrines outside the city's religious boundary. Rather, his action served to reassert the Roman openness to foreign religions while at the same time underlining the distinctions between Roman and foreign religious practices. Using the pomerium to demarcate a clear boundary between Roman and non-Roman helped to reconstruct the sense of Roman identity that had been shattered by the civil wars of the previous fifty years.
Reining in the Passions: The Allegorical Interpretation of Parmenides B Fragment 1
Authors: Latona Max J.
Published: July 2008

This article attempts to determine whether Parmenides intended the chariot imagery of his poem to be construed allegorically, as argued by Sextus Empiricus. Modern interpreters have rejected the allegorical reading, arguing that Sextus was biased by Plato, the allegory's true author. There are, however, reasons to believe that a tradition (either native or imported) of employing the chariot image allegorically preexisted Plato and Parmenides. This article argues that Parmenides was drawing upon such a tradition and did portray mind as a charioteer upon a path of knowledge, and impulse as the horses, requiring guidance in order to reach the destination.
Spectacle, Exoticism, and Display in the Gentleman’s House: The Fonthill Auction of 1822
Authors: Richter Anne Nellis
Published: July 2008

This essay examines the reaction of the public and periodical press to the exhibition and sale of William Beckford’s country estate. The specific circumstances of Beckford’s notoriety and unconventional tastes, the conjunction of exhibition and sale, and the publicity surrounding the auction undermined the conventional ideology of the country house and transgressed categories of exhibiting, display, and viewing in a number of significant ways; by analyzing the points of friction characterizing the exhibition’s reception I will reveal what was at stake in the struggle for cultural authority, here manifested as public display and gentlemanly taste, in the early nineteenth century.