bluuebunny/crossref_metadata_2025 huggingface dataset:
Switching of Response Modalities
Authors: Philipp Andrea M. , Koch Iring
Published: March 2005

When participants perform a sequence of different tasks, it is assumed that the engagement in one task leads to the inhibition of the previous task. This inhibition persists and impairs performance when participants switch back to this (still inhibited) task after only one intermediate trial. Previous task-switching studies on this issue have defined different tasks at the level of stimulus categorization. In our experiments we used different response modalities to define tasks. Participants always used the same stimulus categorization (e.g., categorize a digit as odd vs. even), but had to give a vocal, finger, or foot response (A, B, or C). Our results showed a higher reaction time and error rate in ABA sequences than in CBA sequences, indicating n − 2 repetition cost as a marker for persisting task inhibition. We assume that different response modalities can define a task and are inhibited in a “task switch” in the same way as stimulus categories are inhibited.
Study and comparison of two polishing methods for platinum–iridium surfaces, by means of three characterization techniques
Authors: Haidar Y , Tollens E , Silvestri Z , de Fornel F , Zerrouki C , Picard A , Pinot P
Published: March 2005

Machining the surface of mass standards is still of great importance. This paper details a comparative study of the roughness of two plane surfaces of a platinum–iridium alloy (90% of platinum and 10% of iridium). Using the BIPM processes, the surfaces were initially machined on a lathe using diamond tools; in addition, one of these was manually polished with a diamond paste.

Three techniques for surface characterization are used: shear-force microscopy (ShFM), optical roughness-meter and x-ray reflectometer. The first technique uses the shear-force interaction between the probe and the sample. The ShFM is part of a scanning near-field optical microscope that has the advantage of providing two images simultaneously, a topographical one and a near-field optical one. Only the topographic images will be presented in this paper; the results obtained in optical near-field will be the subject of another publication. To avoid any confusion, we will speak here of ShFM. The topographic images and their associated statistical and physical parameters, such as power spectral densities (PSDs), root-mean-square height, etc, are discussed in this paper. The PSDs of the surface are also determined experimentally from x-ray and visible light scattering measurements using angle-resolved scattering theory. This theory, which is well adapted for visible radiation, is extended to x-rays. The measurements made with the three instruments demonstrate that the two surfaces present a roughness of the same order of magnitude. However, the defects that contribute in a preponderant manner to their roughness spectrum do not belong to the same spatial bandwidth but depend on the polishing process.
Homeostatic Adjustment and Metabolic Remodeling in Glucose-limited Yeast Cultures
Authors: Brauer Matthew J. , Saldanha Alok J. , Dolinski Kara , Botstein David
Published: March 2005

We studied the physiological response to glucose limitation in batch and steady-state (chemostat) cultures of Saccharomyces cerevisiae by following global patterns of gene expression. Glucose-limited batch cultures of yeast go through two sequential exponential growth phases, beginning with a largely fermentative phase, followed by an essentially completely aerobic use of residual glucose and evolved ethanol. Judging from the patterns of gene expression, the state of the cells growing at steady state in glucose-limited chemostats corresponds most closely with the state of cells in batch cultures just before they undergo this “diauxic shift.” Essentially the same pattern was found between chemostats having a fivefold difference in steady-state growth rate (the lower rate approximating that of the second phase respiratory growth rate in batch cultures). Although in both cases the cells in the chemostat consumed most of the glucose, in neither case did they seem to be metabolizing it primarily through respiration. Although there was some indication of a modest oxidative stress response, the chemostat cultures did not exhibit the massive environmental stress response associated with starvation that also is observed, at least in part, during the diauxic shift in batch cultures. We conclude that despite the theoretical possibility of a switch to fully aerobic metabolism of glucose in the chemostat under conditions of glucose scarcity, homeostatic mechanisms are able to carry out metabolic adjustment as if fermentation of the glucose is the preferred option until the glucose is entirely depleted. These results suggest that some aspect of actual starvation, possibly a component of the stress response, may be required for triggering the metabolic remodeling associated with the diauxic shift.
Reconciling Conflicting Gauss-Markov Conditions in the Classical Linear Regression Model
Authors: Larocca Roger
Published: March 2005

This article reconciles conflicting accounts of Gauss-Markov conditions, which specify when ordinary least squares (OLS) estimators are also best linear unbiased (BLU) estimators. We show that exogeneity constraints that are commonly assumed in econometric treatments of the Gauss-Markov theorem are unnecessary for OLS estimates of the classical linear regression model to be BLU. We also generalize a set of necessary and sufficient conditions first established by McElroy (1967,Journal of the American Statistical Association62:1302–1304), but not yet generally recognized in the econometric literature, that are appropriate for many political science applications. McElroy's conditions relax the traditional Gauss-Markov restriction on autocorrelation in the errors to allow a type of correlation, exchangeability, that has two desirable characteristics: (1) exchangeable data occur in a potentially important class of political science models, and (2) the form of autocorrelation that occurs in exchangeable data has a ready intuition. We thus show that a common class of sample selection models that does not satisfy the Gauss-Markov conditions specified in econometrics textbooks is, in fact, BLU under OLS estimation.
The vlhA loci of Mycoplasma synoviae are confined to a restricted region of the genome
Authors: Allen Joanne L. , Noormohammadi Amir H. , Browning Glenn F.
Published: March 2005

Mycoplasma synoviae, a major pathogen of poultry, contains a single expressed, full-length vlhA gene encoding its haemagglutinin, and a large number of vlhA pseudogenes that can be recruited by multiple site-specific recombination events to generate chimaeric variants of the expressed gene. The position and distribution of the vlhA pseudogene regions, and their relationship with the expressed gene, have not been investigated. To determine the relationship between these regions, a physical map of the M. synoviae genome was constructed using the restriction endonucleases SmaI, I-CeuI, BsiWI, ApaI and XhoI and radiolabelled probes for rrnA, recA and tufA. A cloned fragment encoding the unique portion of the expressed vlhA gene and two PCR products containing conserved regions of the ORF 3 and ORF 6 vlhA pseudogenes were used to locate the regions containing these genes on the map. The chromosome of M. synoviae was found to be 890·4 kb and the two rRNA operons were in the same orientation. Both the expressed vlhA gene and the vlhA pseudogenes were confined to the same 114 kb region of the chromosome. These findings indicate that, unlike Mycoplasma gallisepticum, in which the vlhA genes are located in several loci around the chromosome and in which antigenic variation is generated by alternating transcription of over 40 translationally competent genes, M. synoviae has all of the vlhA sequences clustered together, suggesting that close proximity is needed to facilitate the site-specific recombinations used to generate diversity in the expressed vlhA gene.
A new Stroop‐like measure of inhibitory function development: typical developmental trends
Authors: Wright Ingram , Waterman Mitch , Prescott Helen , Murdoch‐Eaton Debbie
Published: March 2005

Background:  Difficulties with inhibition are increasingly regarded as central to pathological behavioural and learning disorders in childhood. However, few measures are available to assist in the assessment of young children's inhibitory competence.

Method:  A new, Stroop‐like measure of inhibitory function is described which was designed to be appropriate for use with children from 3 years of age. One hundred and fifty‐five school children aged between 3 and 16 years took part in a study to examine the developmental characteristics and behavioural correlates of task performance.

Results:  The task appears to provide a robust measure of inhibitory function across the age range, 3 to 16 years. Furthermore, the animal‐stroop task appears to identify those at risk of hyperactive symptomatology within a school‐based sample.

Conclusions:  The clinical and developmental applications of this new measure are discussed.
Psychosocial correlates of depressive symptoms among 12–14‐year‐old Norwegian adolescents
Authors: Sund Anne Mari , Larsson Bo , Wichstrøm Lars
Published: March 2005

Background:  The aim of the study was to examine the relationships between various psychosocial factors and depressive symptoms in early adolescence.

Methods:  A representative sample of 2,465 12–14‐year‐old adolescents comprising 50.8% girls and 49.2% boys, with a mean age of 13.7 years, was recruited in two counties in Norway. The participation rate was 88.3%. Depressive symptoms were measured by the Mood and Feelings Questionnaire (MFQ).

Results:  Correlations between the total sum of stressful events/daily hassles and the total sum of MFQ were moderately high, rs=.49 and rs=.53, respectively. Depressive symptoms were more strongly correlated with school‐related stress among boys than girls, whereas the correlation between daily hassles and depressive symptoms was higher for girls than boys. The results of univariate analyses showed significantly higher mean total MFQ scores among adolescents not living with both natural parents, those who had moved more than twice and those with more than 3 siblings or having fewer than 2 close friends. Further, adolescents from Third World societies and adopted adolescents, those from lower SES groups, having unemployed parents or living in coastal areas had higher mean depressive symptom scores. The results of multiple regression analyses yielded the following six significant predictors of total MFQ scores in order of importance: Sum of daily hassles and sum of stressful life events, gender, number of friends, ethnicity and mother's employment status. Altogether, these variables accounted for 43% of the total variance in MFQ scores.

Conclusions:  It is concluded that these psychosocial predictors should be addressed when assessing depressive symptoms in early adolescence. The findings of the study are discussed in view of previous research in the field and their clinical significance.
Evaluation of the “safe nesting zone” hypothesis across an urban gradient: a multi‐scale study
Authors: Jokimäki Jukka , Kaisanlahti‐Jokimäki Marja‐Liisa , Sorace Alberto , Fernández‐Juricic Esteban , Rodriguez‐Prieto Iñaki , Jimenez Maria Dolores
Published: March 2005

Urban areas have been considered “safe zones” for nesting birds because of low abundance of predators, and consequently low predation pressure. We studied risk of artificial ground nest predation across an urban gradient at regional (100×100 km) and local scales (5×5 km, within town) in Finland, Italy, and Spain. Risk of nest predation differed between countries, being greatest in Spain (66%), intermediate in Finland (51%), and lowest in Italy (29%). At the regional scale, risk of nest predation in Finland was lower in small villages and in forest area than in more urbanized sites. In Spain, the risk of nest predation was lower in villages than in the other habitat types. No differences in nest predation risk among habitat types were observed in Italy. At the local level, the risk of nest predation in Finland was higher within the town than in the surrounding forest. In Spain, the risk of nest predation in the surrounding forest area was as high as in the most urbanized areas. No difference in nest predation risk was observed between study plots in Italy at the local level analysis. Our results indicate that nest predation in town centers and their residential areas is similar to or higher than in villages and forest areas refuting the safe nesting zone hypothesis. Risk of nest predation also differed between residential area types within towns. Moreover, the abundance of potential nest predators differed between countries. Magpies and crows were more abundant in Finland than in Italy and Spain, whereas cats, dogs and pedestrians were less abundant in Finland than in the other countries. In Finland, risk of nest predation increased with the abundance of magpies. In Italy and Spain, risk of nest predation increased with the number of pedestrians and in Italy also with the number of cats. In all countries, the risk of nest predation increased with the visibility of the nest. According to our results, urban areas cannot be seen as “safe nesting zones”. Actually, changes in nest predation pressure may cause changes in habitat selection patterns and affect bird community structure in urban environments.
Unusual feather structure allows partial plumage wettability in diving great cormorants Phalacrocorax carbo
Authors: Grémillet David , Chauvin Christophe , Wilson Rory P. , Le Maho Yvon , Wanless Sarah
Published: March 2005

The great cormorant Phalacrocorax carbo is thought to have a wettable plumage, providing low body insulation during foraging. Great cormorants should thus be constrained by water temperatures, and show high energy requirements. Surprisingly, this species has one of the widest breeding distributions of all diving birds, and does not require more food than these other species. We explored this apparent paradox by comparing the insulative properties of body plumage in four subspecies of great cormorants ranging from tropical to polar regions. We found that all subspecies retained an insulating air layer in their plumage, which was, however, much thinner than for other species of diving birds. Detailed examination of the plumage showed that each cormorant body feather has a loose, instantaneously wet, outer section and a highly waterproof central portion. This indicates that the plumage of great cormorants is only partly wettable, and that birds maintain a thin layer of air in their plumage. Our findings suggest an unusual morphological‐functional adaptation to diving which balances the antagonist constraints of thermoregulation and buoyancy.
Status of climacteric symptoms among middle‐aged to elderly Japanese women: Comparison of general healthy women with women presenting at a menopausal clinic
Authors: Ikeda Toshiyuki , Makita Kazuya , Ishitani Ken , Takamatsu Kiyoshi , Horiguchi Fumi , Nozawa Shiro
Published: March 2005

Aim: To examine the status and characteristics of climacteric symptoms reported by generally healthy middle‐aged to elderly women in Japan, those living in Saitama Prefecture were surveyed .

Methods: The subjects comprised 398 women ranging in age from 40 to <60 years (mean age, 50.5 years). Climacteric symptoms were objectively assessed using the Keio questionnaire. The total scores obtained for the 40 symptoms were used to calculate symptom prevalence and severity.

Results: (i) The most frequent symptom was poor memory, reported by 88.7% of the women. (ii) Lumbar‐sacral back pain was rated as a severe symptom by the highest percentage of women (15.3%). (iii) The prevalence and severity of poor memory and lumbar‐sacral back pain did not differ with menopausal status. (iv) Hot flashes and sweats were slightly higher in peri‐ and early postmenopausal women than in premenopausal women.

Conclusions: The present study showed that healthy women who do not consult physicians because of climacteric symptoms are primarily concerned with age‐related symptoms, such as poor memory, loss of hair, and forgetfulness.
Rapid incorporation of carbon from fresh residues into newly formed stable microaggregates within earthworm casts
Authors: Bossuyt H. , Six J. , Hendrix P. F.
Published: March 2005

Earthworms play an important role in protecting carbon in the soil, but the exact influence of their activity on the distribution and protection of C is still poorly understood. We investigated the effect of earthworms on the formation of stable microaggregates inside newly formed macroaggregates and the distribution of C in them. We crushed (< 250 µm) soil, and subjected it to three treatments: (i) soil + 13C‐labelled residue + earthworms (these added after 8 days' incubation), (ii) soil + 13C‐labelled residue, and (iii) control (no additions), and then incubated it for 20 days. At the end, we measured the aggregate size distribution, total C and 13C, and we isolated microaggregates (53–250 µm) from macroaggregates (> 250 µm) formed. The 13C in fine particulate organic matter between and within the microaggregates was determined. Earthworms helped to form large macroaggregates (> 2000 µm). These large macroaggregates contained four times more stable microaggregates than those from samples without earthworms. There was more particulate organic matter within and between microaggregates in macroaggregates in the presence of earthworms. The larger amounts of organic matter inside stable microaggregates in casts than in bulk soil after 12 days of incubation (140 mg 13C kg−1 soil compared with 20 mg 13C kg−1 soil) indicates that these microaggregates are formed rapidly around freshly incorporated residues within casts. In conclusion, earthworms have a direct impact on the formation of stable microaggregates and the incorporation of organic matter inside these microaggregates, and it seems likely that their activity is of great significance for the long‐term stabilization of organic matter in soils.
High‐dose vitamin E supplementation does not diminish ribavirin‐associated haemolysis in hepatitis C treatment with combination standard α‐interferon and ribavirin
Authors: Saeian K. , Bajaj J. S. , Franco J. , Knox J. F. , Daniel J. , Peine C. , McKee D. , Varma R. R. , Ho S. ,   Midwest Hepatitis Study Group
Published: March 2005

Background: Ribavirin is associated with haemolytic anaemia. Antioxidants have been reported to decrease severity of this anaemia.

Aim: To determine effect of vitamin E supplementation on ribavirin‐associated haemolysis in chronic hepatitis C treated with standardα‐interferon and ribavirin.

Methods: Fifty‐one naive chronic hepatitis C patients were randomized to receive eitherα‐interferon/ribavirin therapy (control) or therapy plus vitamin E 800 IU b.d. with 24‐week follow‐up. Alanine aminotransferase ALT, haemoglobin and reticulocyte percentage were monitored. Symptoms and health‐related quality of life were also monitored at each visit.

Results: Forty‐seven subjects were treated (27 vitamin E /20 controls). Thirteen withdrew because of adverse effects or non‐compliance. Groups were similar in demographics, genotype and baseline lab indices. Comparison with baseline, treatment and follow‐up values showed a significant haemoglobin and ALT reduction in both groups. There was no significant difference in haemoglobin and reticulocyte percentage between groups. Sustained viral response was not significantly different between vitamin E (11/18) and control (6/16) groups. Three patients required ribavirin dose‐reduction in the vitamin E group compared with two controls. Health‐related quality of life during and end‐of‐treatment was not different between groups.

Conclusions: Vitamin E supplementation alone during standardα‐interferon and ribavirin therapy does not appear to diminish ribavirin‐associated haemolysis.
Mobilization of dissolved organic matter, aluminium and iron in podzol eluvial horizons as affected by formation of metal‐organic complexes and interactions with solid soil material
Authors: Jansen B. , Nierop K. G. J. , Verstraten J. M.
Published: March 2005

Interactions with dissolved organic matter (DOM) are generally believed to play a crucial role in the translocation of Al and Fe in acid sandy soils. Binding of Al and Fe to DOM affects their mobility in soils by altering sorption equilibria of charged sites on solid soil material, inducing precipitation of organo‐metallic complexes and preventing the formation of inorganic Al and Fe phases. The relative importance of the different processes, especially with respect to the translocation of Al, Fe and organic matter in podzols, remains unresolved. We determined the effect of the presence of solid soil material from the eluvial (AhE and AE, respectively) horizons of a Fimic Anthrosol and a Haplic Podzol on the metal‐to‐organic carbon (M/C) ratio in solution and the formation of dissolved organic Al and Fe complexes. Furthermore, we assessed the resulting influence on the mobilization of Al, Fe and DOM. Even under considerable metal loading, the M/C ratios and ‘free’ metal fractions in solution remained low and relatively constant, due to an apparent buffering by the solid phase and the formation of organo‐metal complexes in solution. The M/C ratios remained so low that significant precipitation of organo‐metal complexes due to saturation with metals was not found. The apparent buffering by the solid phase can be explained by a strong release of organic matter from solid soil material and adsorption of non‐complexed Al and Fe on solid organic matter upon metal addition. Adsorption of organo‐metal complexes most likely played only a minor role. The observations confirm the expected mobilization of Al, Fe and DOM in eluvial horizons and seem to indicate that even under fluctuating input of Al, Fe and DOM the soil solution will have a constant composition with respect to M/C ratios and percentage of Al and Fe present in dissolved organo‐metal complexes.
Emissions of N2O from soils during cycles of freezing and thawing and the effects of soil water, texture and duration of freezing
Authors: Teepe R. , Vor A. , Beese F. , Ludwig B.
Published: March 2005

Freezing and thawing influence many physical, chemical and biological processes in soils, including the production of trace gases. We studied the effects of freezing and thawing on three soils, one sandy, one silty and one loamy, on the emissions of N2O and CO2. We also studied the effect of varying the water content, expressed as the percentage of the water‐filled pore space (WFPS). Emissions of N2O during thawing decreased in the order 64% > 55% > 42% WFPS, which suggests that the retardation of the denitrification was more pronounced than the acceleration of the nitrification with increasing oxygen concentration in the soil. However, emissions of N2O at 76% WFPS were less than at 55% WFPS, which might be caused by an increased ratio of N2/N2O in the very moist conditions. The emission of CO2 was related to the soil water, with the smallest emissions at 76% WFPS and largest at 42% WFPS. The emissions of CO2 during thawing exceeded the initial CO2 emissions before the soils were frozen, which suggests that the supply of nutrients was increased by freezing. Differences in soil texture had no marked effect on the N2O emissions during thawing. The duration of freezing, however, did affect the emissions from all three soils. Freezing the soil for less than 1 day had negligible effects, but freezing for longer caused concomitant increases in emissions. Evidently the duration of freezing and soil water content have important effects on the emission of N2O, whereas the effects of texture in the range we studied were small.
The influence of cultivar and cultivar‐aphid odours on the olfactory response of the parasitoid Aphidius colemani
Authors: Kalule T. , Wright D. J.
Published: March 2005

The olfactory response of the parasitoid Aphidius colemani (Viereck) (Hymenoptera: Braconidae) to odours in a tritrophic system involving three cultivars of common cabbage, Brassica oleracea var capitata, characterized by different levels of susceptibility to Myzus persicae (Sulzer) (Hemiptera: Aphididae) was studied in a four‐way olfactometer. Odours influenced A. colemani response in the olfactometer to varying degrees. The magnitude of parasitoid response to odours of uninfested cabbage depended on cultivar, with Derby Day [green‐leaved, susceptible to M. persicae and the crucifer specialist, Brevicoryne brassicae (Linnaeus) (Hemiptera: Aphididae)] and Minicole (green‐leaved, partially resistant with known antibiosis factors for B. brassicae) preferred over Ruby Ball (red‐leaved with antixenosis factors for M. persicae and B. brassicae). The odour of the cabbage cultivar on which the parasitoid had been reared was preferred over the other cultivars. However, when provided with a choice between odours of infested plants, parasitoids did not show a significant preference for the cultivar on which they were reared. Results from the study show that parasitioids differentiated between odour of the three cultivars in dependence of their rearing history when the plant is uninfested.
Mating disruption barriers in pome fruit for improved control of oriental fruit moth Grapholita molesta Busck (Lep., Tortricidae) in stone fruit under mating disruption
Authors: Il'ichev A. L. , Williams D. G. , Milner A. D.
Published: March 2005

Oriental fruit moth (OFM) Grapholita molesta Busck (Lep., Tortricidae) is a very important pest in commercial orchards in Victoria, Australia. Pheromone‐mediated mating disruption (MD) applied in stone fruit orchards successfully controlled OFM populations for many years, but damage to shoot tips and fruit at the edge of peach blocks located adjacent to pear blocks under insecticide treatments has become problematic. To improve protection of stone fruit against edge damage and outbreaks of OFM, all orchards were treated with sex pheromone dispensers for MD on an area‐wide basis. Area‐wide MD treatment, including all pome and stone fruit orchards in a discrete area, successfully controlled edge infestations of OFM, but was expensive. To reduce the cost of OFM control, sex pheromone dispensers for MD were applied as barrier treatments to 54–60 m of neighbouring pears adjacent to peaches under MD. Detailed monitoring of the OFM population, shoot tip and fruit damage assessments indicated that application of MD barriers on pears during two consecutive seasons provided sufficient control of OFM on peaches. This MD barrier treatment was able to reduce the number of OFM caught in all experimental peach blocks, with damage to shoot tips and fruit giving similar results to MD treatment of the whole neighbouring pear block. Extending the MD treatment area for 54–60 m into the neighbouring pear block significantly reduced the edge damage in MD‐treated peaches in the first season and almost eliminated OFM damage in the second season.
Functional and numerical responses of Propylea dissecta (Col., Coccinellidae)
Authors: Omkar  , Pervez A.
Published: March 2005

The functional response of a ladybeetle, Propylea dissecta, to increasing density of aphid, Aphis gossypii, was of the curvilinear shape depicting Holling's type II response with fourth instar larva being the most voracious stage when compared with adult male and female. Prey handling time by different predatory stages decreased from 65.45 to 8.72 min with increase in prey density from 25 to 800. The predator aggregation and high prey density reduces the searching efficiency of the predator. Area of discovery was highest (1.4437) when a single predator was searching at minimum aphid density (25) and lowest (0.0366) when eight predators were searching at a constant aphid density (200). Mutual interference and quest constants were 0.75 and 0.40, respectively. The reproductive numerical response, in terms of eggs laid, increased curvilinearly with prey density and female laid 70.5 ± 5.55 eggs when exposed to highest prey density (400) and 12.3 ± 0.79 eggs at lowest prey density (10). The similar shapes of both functional and reproductive responses indicate that both responses are interlinked and function simultaneously.
What is heterosexual coercion? Interpreting narratives from young people in Mexico City
Authors: Marston Cicely
Published: March 2005

Abstract Freedom from sexual coercion is frequently cited as essential for good sexual health. Sexual experiences cannot usually be observed directly, and interpretation of interview data is therefore crucial in our understanding of sexual behaviour. This paper explores the ways in which narratives can be used to understand sexual experiences, using coercion as a specific example. The narratives examined are from interviews with young people in low‐income areas of Mexico City. This study demonstrates that sexual coercion is impossible to define objectively. In addition, the concept of coercion is focused too much on women, excluding men's negative sexual experiences, and can include events that the ‘victims’ do not see as coercive. Coercion is a highly subjective and fluid concept, limiting its value as a defining element of sexual health. An alternative way of conceptualising coercive experiences is suggested.
Niche construction through phenological plasticity: life history dynamics and ecological consequences
Authors: Donohue Kathleen
Published: March 2005

The ability of an organism to alter the environment that it experiences has been termed ‘niche construction’. Plants have several ways whereby they can determine the environment to which they are exposed at different life stages. This paper discusses three of these: plasticity in dispersal, flowering timing and germination timing. It reviews pathways through which niche construction alters evolutionary and ecological trajectories by altering the selective environment to which organisms are exposed, the phenotypic expression of plastic characters, and the expression of genetic variation. It provides examples whereby niche construction creates positive or negative feedbacks between phenotypes and environments, which in turn cause novel evolutionary constraints and novel life‐history expression.
Mortality Benefit of Transfer to Level I versus Level II Trauma Centers for Head‐Injured Patients
Authors: McConnell K. John , Newgard Craig D. , Mullins Richard J. , Arthur Melanie , Hedges Jerris R.
Published: March 2005

Objective. To determine whether head‐injured patients transferred to level I trauma centers have reduced mortality relative to transfers to level II trauma centers.

Data Source/Study Setting. Retrospective cohort study of 542 patients with head injury who initially presented to 1 of 31 rural trauma centers in Oregon and Washington, and were transferred from the emergency department to 1 of 15 level I or level II trauma centers, between 1991 and 1994.

Study Design. A bivariate probit, instrumental variables model was used to estimate the effect of transfer to level I versus level II trauma centers on 30‐day postdischarge mortality. Independent variables included age, gender, Injury Severity Scale (ISS), other indicators of injury severity, and a dichotomous variable indicating transfer to a level I trauma center. The differential distance between the nearest level I and level II trauma centers was used as an instrument.

Principal Findings. Patients transferred to level I trauma centers differ in unmeasured ways from patients transferred to level II trauma centers, biasing estimates based on standard statistical methods. Transfer to a level I trauma center reduced absolute mortality risk by 10.1% (95% confidence interval 0.3%, 22.2%) compared with transfer to level II trauma centers.

Conclusions. Patients with severe head injuries transferred from rural trauma centers to level I centers are likely to have improved survival relative to transfer to level II centers.
The HemoCue®for point‐of‐care hemoglobin measurement and packed cell volume estimation in cats
Authors: Posner Lysa P. , Erb Hollis N. , Gleed Robin D.
Published: March 2005

Objective:To determine conversion formulas so that values from the HemoCue®hemoglobinometer (HbHQ) could be equated to hemoglobin concentrations measured by the gold‐standard cyanomethemoglobin (HbCY) method and used for estimation of packed cell volume (PCV) in cats.

Study design:Prospective,in vitro.

Animals:Twelve healthy, adult, client‐owned cats.

Interventions:The PCV of 12 parent blood samples was manipulated between ∼3 and ∼80% by removing or adding autologous plasma. Hemoglobin was measured by the HbCYmethod at a university clinical pathology laboratory and by the azidemethemoglobin method in a HbHQ. PCV was determined by micro‐centrifugation.

Measurements and main results:Hemoglobin varied from 1–26 g/dL. Repeated‐measures regression of HbCYon HbHQdemonstrated that theY‐intercept was not different from zero. When the regression was repeated, forcing the line through the origin the coefficient for converting HbHQto HbCYwas not significantly different from 1.0 (adjustedR2=99.7%). The conversion formula was HbCY=HbHQ. Using similar methods, the conversion formula for estimating PCV was PCV=3.1 HbHQ(adjustedR2=99.8%).

Conclusion:Hemoglobin concentration measured by the HemoCue®was indistinguishable from the (HbCY) method in feline blood over a wide range of hemoglobin concentrations. This study demonstrates that in cats PCV=3.1HbHQ.

Clinical relevance:The HemoCue®is useful for point‐of‐care hemoglobinometry and for estimating PCV in cats.
Role of Helicobacter pylori in Gastric Carcinogenesis: The Origin of Gastric Cancers and Heterotopic Proliferative Glands in Mongolian Gerbils
Authors: Tatematsu Masae , Tsukamoto Tetsuya , Mizoshita Tsutomu
Published: March 2005

Helicobacter pylori infection is well accepted to be a very important factor for the development of gastric carcinogenesis in the human stomach. In Mongolian gerbils treated with chemical carcinogens, H. pylori infection enhances glandular stomach carcinogenesis, and eradication of infection and results in curtailment of enhancing effects, particularly at early stages of associated inflammation. A high‐salt diet exacerbates the effects of H. pylori infection on gastric carcinogenesis, and these two factors act synergistically to promote the development of gastric cancers in this animal model. However, the bacterium exerts the greater effects. Early acquisition significantly increases gastric chemical carcinogenesis in Mongolian gerbils, as compared to later infection. While heterotopic proliferative glands, hyperplastic and dilated glands localized beneath the muscularis mucosae, frequently develop with H. pylori infection alone in this animal model, they obviously regress on eradication, suggesting a relation to severe gastritis, rather than a malignant character. Furthermore, endocrine cells, positive for chromogranin A, are observed in the heterotopic proliferative glands, in contrast to cancerous lesions which lack endocrine elements. In conclusion, H. pylori is not an initiator, but rather a strong promoter of gastric carcinogenesis, whose eradication, together with reduction in salt intake, might effectively prevent gastric cancer development.
Effect of the Carbonic Anhydrase Inhibitor, Acetazolamide, on Helicobacter pylori Infection in vivo: A Pilot Study
Authors: Shahidzadeh Rassa , Opekun Antone , Shiotani Akiko , Graham David Y.
Published: March 2005

Background.   Carbonic anhydrase inhibitors have been successfully used to treat peptic ulcers. Although carbonic anhydrase restriction does not inhibit Helicobacter pylori in vitro, recent studies suggest that carbonic anhydrase inhibition reduces the ability of H. pylori to survive in an acid environment as present in the stomach.

Methods.   In a pilot study, we examined the effect of acetazolamide 500 mg as twice a day for 4 days in volunteers with active H. pylori infection. Effectiveness was judged by changes in the results of the urea breath test.

Results.   Eight H. pylori infected volunteers completed the test. No urea breath test reverted to negative and there was a trend for the urea breath test value to increase [e.g. delta over baseline (DOB) mean ± SE increased from 50.9 ± 13 at baseline to 64.9 ± 13 at day 5] during treatment with acetazolamide.

Conclusion.   The potential effect of carbonic anhydrase inhibitors on acid secretion may prevent effect on H. pylori in vivo and/or the sites of infection at the surface of the stomach may have a pH higher for any postulated acid‐dependent effect to have an effect clinically.
Histological quantitation of tumour angiogenesis
Authors: FOX STEPHEN B. , HARRIS ADRIAN L.
Published: March 2005

Tumours establish their blood supply via a number of processes in addition to angiogenesis. These include vasculogenesis, vascular remodelling, intussusception and possibly vascular mimicry in certain tumours. The mainstay of the assessment of tumour vascularity has been counting the number of immunohistochemically identified microvessels in vascular hot spots. Nevertheless, several other techniques are available, including Chalkley counting, vascular grade and the use of image analysis systems. Angiogenic activity can furthermore be assessed in histological samples by measuring the molecules involved in the establishment of the tumour vasculature, including angiogenic growth factors and their receptors, cell adhesion molecules, proteases and markers of activated, proliferating, cytokine stimulated or angiogenic vessels, such as CD105. Measuring the maturity of vessels may give an indication of the proportion of the tumour vasculature that is functional. Other reagents that can identify hypoxia‐activated pathways are also being developed. The histological assessment of tumour vascularity is mainly used in the research setting but may also have applications in the clinic if appropriate methodology and trained observers perform the studies. Gene arrays may be able to provide an angiogenesis profile. Continued study into the processes involved in generating a tumour blood supply is likely to identify new markers that may be more accurate measures.
Mice Lacking the Major Adult GABAA Receptor Subtype Have Normal Number of Synapses, But Retain Juvenile IPSC Kinetics Until Adulthood
Authors: Bosman Laurens W. J. , Heinen Klaartje , Spijker Sabine , Brussaard Arjen B.
Published: March 2005

There is a large variation in structurally and functionally different GABAA receptor subtypes. The expression pattern of GABAA receptor subunits is highly regulated, both temporarily and spatially. Especially during development, profound changes in subunit expression have been described. In most brain areas, the GABAA receptor α1 subunit replaces the α2 and/or α3 subunit as major α subunit. This is accompanied by a marked decrease in the open time of GABAA receptors and hence in the duration of postsynaptic responses. We describe here the development of GABAergic, synaptic transmission in mice lacking the α1 subunit. We show that α1 is to a large extent—but not entirely—responsible for the relatively short duration of postsynaptic responses in the developing and the mature brain. However, α1 already affects GABAergic transmission in the neonatal cerebral cortex when it is only sparsely expressed. It appears that the α1 −/− mice do not show a large reduction in GABAergic synapses but do retain long-lasting postsynaptic currents into adulthood. Hence, they form a good model to study the functional role of developmental GABAA receptor subunit switching.
Regional and Laminar Differences in In Vivo Firing Patterns of Primate Cortical Neurons
Authors: Shinomoto Shigeru , Miyazaki Youichi , Tamura Hiroshi , Fujita Ichiro
Published: March 2005

The firing rates of cortical neurons change in time; yet, some aspects of their in vivo firing characteristics remain unchanged and are specific to individual neurons. A recent study has shown that neurons in the monkey medial motor areas can be grouped into 2 firing types, “likely random” and “quasi-regular,” according to a measure of local variation of interspike intervals. In the present study, we extended this analysis to area TE of the inferior temporal cortex and addressed whether this classification applies generally to different cortical areas and whether different types of neurons show different laminar distribution. We found that area TE did consist of 2 groups of neurons with different firing characteristics, one similar to the “likely random” type in the medial motor cortical areas, and the other exhibiting a “clumpy-bursty” firing pattern unique to TE. The quasi-regular type was rarely observed in area TE. The likely random firing type of neuron was more frequently found in layers V–VI than in layers II–III, whereas the opposite was true for the clumpy-bursty firing type. These results show that neocortical areas consist of heterogeneous neurons that differ from one area to another in their basic firing characteristics. Moreover, we show that spike trains obtained from a single cortical neuron can provide a clue that helps to identify its layer localization.
Global Capitalism and the Flow of Foreign Direct Investment to Non-Core Nations, 1980-1996: A Quantitative, Cross-National Analysis
Authors: Shandra John M. , Ross Robert J. S. , London Bruce
Published: March 2005

This paper updates an earlier quantitative cross-national study (London and Ross 1995) by examining a more recent time period and re-specifying the original model in a number of significant ways. These include the incorporation of measures of (a) International Monetary Fund penetration into non-core nations (demonstrating that IMF conditionality increases the flow of FDI), (b) the presence of “attractive investment opportunities” in nations (to incorporate a predictor suggested by neoclassical economic theory), and (c) an interaction term that points to the multiplicative significance of intranational and international factors. Our findings generally confirm those of the earlier study and produce some significant new results.
Journey into Nothingness: Structure of the Mental Entity—Shlomo Giora Shoham’s Personality Theory
Authors: Lev Yossi
Published: March 2005

Shoham’s theory of personality divides the entity of the mind into two main structures: The “self” and the “I.” While the “self” (which is the component in an entity that aspires to interact with the outside environment) appears in some form or other in all theories of personality, the “I” is unique to Shoham’s theory. This is the component that aspires to return to the undefined pre-existential state, to “nothingness.” This article discusses Shoham’s contribution to the theory of personality. It concludes that the “I” is an additional structure to the existing personality theories. Therefore an attempt is made to present a model that combines the “I” with the classical psychoanalytical theory, and to suggest three structures inside the “I”: The one, the being, and the nothingness.
Street Children and the Excluded Class
Authors: De Venanzi Augusto
Published: March 2005

Traditionally, the study of street children has proceeded by locating these kids in social categories such as the poor, the destitute, the vulnerable population or the population at risk. Other scholarly traditions have advanced the view that street children belong with the socially excluded groups. However, both approaches treat these children as if their life experiences are not linked to the general class structure and the State. The argument I advance in this article is that an improved understanding of street children’s everyday existence is to include them in a social class, namely: the socially excluded class. I argue that the class and exclusion paradigms are well suited to one another insofar as some excluded persons participate in the division of labor. The proposed approach leads us to focus upon a set of empirical dimensions related to the lives of street children: their commonality of experience, their exploitation of social capital as a means for survival, their participation in the division of labor, their relational experience and the nature of the collective action they engage in to defend their interests. I conclude by arguing that this approach constitutes a comprehensive analytical framework that allows us to better organize and obtain knowledge concerning the social life of street children.
A Silk Purse From the Sow's Ear: Retrieving Normative Information From Multidimensional Forced-Choice Items
Authors: McCloy Rodney A. , Heggestad Eric D. , Reeve Charlie L.
Published: March 2005

This article presents a psychometric approach for extracting normative information from multidimensional forced-choice (MFC) formats while retaining the method's faking-resistant property. The approach draws on concepts from Coombs's unfolding models and modern item response theory to develop a theoretical model of the judgment process used to answer MFC items, which is then used to develop a scoring system that provides estimates of normative trait standings.
A Taxonomic Search Engine: Federating taxonomic databases using web services
Authors: Page Roderic DM
Published: March 2005

Background

The taxonomic name of an organism is a key link between different databases that store information on that organism. However, in the absence of a single, comprehensive database of organism names, individual databases lack an easy means of checking the correctness of a name. Furthermore, the same organism may have more than one name, and the same name may apply to more than one organism.

Results

The Taxonomic Search Engine (TSE) is a web application written in PHP that queries multiple taxonomic databases (ITIS, Index Fungorum, IPNI, NCBI, and uBIO) and summarises the results in a consistent format. It supports "drill-down" queries to retrieve a specific record. The TSE can optionally suggest alternative spellings the user can try. It also acts as a Life Science Identifier (LSID) authority for the source taxonomic databases, providing globally unique identifiers (and associated metadata) for each name.

Conclusion

The Taxonomic Search Engine is available at http://darwin.zoology.gla.ac.uk/~rpage/portal/ and provides a simple demonstration of the potential of the federated approach to providing access to taxonomic names.
Interaction of Copper-Containing Preservatives with Wood. Part 1. Mechanism of the Interaction of Copper with Cellulose
Authors: Druz N. , Andersone I. , Andersons B.
Published: March 2005

In the present work, the state of the copper ions absorbed by cellulose from aqueous solutions with different
pH values has been studied by electron spin resonance (ESR), X-ray photoelectron spectroscopy
(XPS) and energy-dispersive X-ray analysis (EDXA) methods. It has been shown that the curve of
copper sorption has a S-like shape characteristic for weak acid sorbents. At all pH values in ESR-spectra,
an anisotropic Cu(II)-signal is registered. At pH > 4, the anisotropy of ESR-spectra decreases.
At pH = 10, complexes connected by exchange interactions and diamagnetic clusters are formed. After
the leaching of specimens, the ESR-signal practically disappeared. The decrease of the copper content
in cellulose did not correlate with the change of the integral intensity of the spectra. The changes in ESR-spectra
of copper-containing cellulose after leaching were explained by the formation of the Cu(II) diamagnetic
clusters.