bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gray Peril or Loyal Support? The Effects of the Elderly on Educational Expenditures*
Authors: Berkman Michael B. , Plutzer Eric 
Published: December 2004

Objectives. Do large concentrations of elderly represent a “gray peril” to maintaining adequate educational expenditures? The gray peril hypothesis is based on an assumption of instrumental self‐interest in political behavior. In contrast, we argue that loyalty to community schools competes with economic self‐interest and that older citizens are heterogeneous in their preferences.Methods. We test these arguments and their implications for public school finance using a data set of more than 9,000 school districts.Results. The data show that longstanding older residents represent a source of support for educational expenditures while elderly migrants lower spending. Further, this divide among the elderly and their impact on policy outputs depends on how states finance local public education and on aspects of state and local tax policy.Conclusions. Elderly concentrations are a financial asset for a school district unless the senior community includes a large number of new arrivals. The design of tax policy can have enormous impact on the depth of political cleavages and their ultimate impact on public policy. The results are consistent with the idea that loyalty—an emotional bond between residents and their community's institutions—competes with and often trumps instrumental self interest.
Family Resources, Gender, and Immigration: Changing Sources of Hong Kong Educational Inequality, 1971–2001*
Authors: Post David 
Published: December 2004

Objective.This study gauged the impact of government‐led educational expansion on Hong Kong's social stratification over a 30‐year period. The historically close state control over school supply in Hong Kong allows us to test the effectiveness of public policy in changing the transmission of advantages across generations.Methods.I analyzed household‐level census data from 1971, 1981, 1991, and 2001. Interviews and documents were also used to illuminate reasons for trends during this period.Results.There was a diminishing role of family resources and gender on access to all levels of schooling until 1991. From 1991 through 2001, however, there was a reversal of this trend at the postsecondary level, as access to university education became more dependent on family resources. In addition, new immigrants from mainland China were at an increased disadvantage.Conclusions.Hong Kong's current plan to create a second tier of self‐supporting postsecondary institutions will exacerbate the tendency toward unequal university access, and is also likely to segregate new arrivals from mainland China.
The Interplay Between Social and Cultural Determinants of School Effort and Success: An Investigation of Chinese‐Immigrant and Second‐Generation Chinese Students' Perceptions Toward School*
Authors: Kaufman Julia 
Published: December 2004

Objective. Educational research suggests that close‐knit, supportive immigrant communities can encourage students' school success; however, less agreement exists about why students outside of those communities—particularly in urban areas—do not always do as well in school, even when those students perceive themselves to be working as hard as their higher‐performing immigrant peers. This article explores the relationship between Chinese‐immigrant and second‐generation Chinese students' perceptions and social/cultural factors that influence their lives in a large urban school.Methods. Longitudinal interviews with students, as well as observations at the school, took place from September 2000 to May 2001.Results. Chinese immigrants in this study are motivated to work hard and value demanding teachers, difficult curriculum, and discipline more than their second‐generation Chinese peers; the second‐generation students talk of wanting more entertaining, knowledgeable teachers while not being willing or able to work as hard for school success.Conclusions. These findings indicate that differences in students' perceptions of their own effort and success in school may depend greatly on the social environment in which students find themselves, as well as the culturally‐driven actions available within those environments.
Low‐Income Students and College Attendance: An Exploration of Income Expectations*
Authors: Rouse Cecilia Elena 
Published: December 2004

Objectives. Some have hypothesized that unrealistic expectations regarding their futures may explain the weak link between expectations and realizations among low‐income (particularly minority) youth. Unfortunately, there is little evidence characterizing students' expectations around the time that they make college decisions that would allow one to study this hypothesis.Methods. In this exploratory article, I analyze data on income expectations from a small sample of low‐income minority high school seniors in Baltimore City, MD; and use data from Dominitz and Manski's sample of higher‐income white students in Madison, WI, and the NELS88 for comparisons.Results. I find little evidence that the income expectations of lower‐income minority students are so different from those of higher‐income students. Rather, the expected returns to postsecondary education appear similar between the two samples of high school seniors. Analysis of a nationally representative sample of high school seniors suggests that lower‐income students do not place less weight on expected economic returns to college when making their plans than do more advantaged students, although low‐income students are less able to translate their college plans into actual college attendance.Conclusions. These results suggest that differing income expectations do not explain the weaker relationship between expectations and educational attainment among low‐income students.
Effect of low‐dose warfarin on D‐dimer levels during sickle cell vaso‐occlusive crisis: a brief report
Authors: Ahmed Shahid , Siddiqui Anita K. , Iqbal Uzma , Sison Cristina P. , Shahid Rabia K. , Sheth Manish , Patel Dilip V. , Russo Linda A. 
Published: December 2004

Abstract:Objective : To evaluate the activation of clotting systems in patients with sickle cell disease (SCD) by measuring the plasma D‐dimer level and to determine the effect of low‐dose warfarin on D‐dimer level during vaso‐occlusive crisis.Methods : Plasma D‐dimer level was measured in 65 blood samples of 37 adult patients with SCD who were hospitalized for vaso‐occlusive painful crisis. D‐dimer level of patients who were on low‐dose warfarin was compared with those patients who were not on any anticoagulation treatment. Analysis of variance (anova) was carried out to determine factors significantly associated with low D‐dimer level in patients with SCD. The following factors were included in the anova model; warfarin, homozygous hemoglobin S, history of blood transfusion in past 3 months, hydroxyurea, hemoglobin S%, hemoglobin F%, white blood cell counts, hemoglobin level, platelet count, and plasma fibrinogen level.Results : Overall median D‐dimer level in 65 samples was 2.7 μg fibrinogen equivalent units (FEU)/mL (0.34–4). Patients who were on low‐dose warfarin had a median D‐dimer level of 0.81 μg FEU/mL (0.34–1.8) compared with 3.1 μg FEU/mL (0.94–4) in those patients who were not on anticoagulation treatment. Using anova to model D‐dimer levels, only warfarin was significantly correlated with low D‐dimer levels after controlling for other variables.Conclusions : Patients with SCD during vaso‐occulsive painful crisis have an elevated D‐dimer level. Low‐dose anticoagulation treatment is associated with a significant reduction in the D‐dimer levels.
Seed beetle survivorship, growth and egg size plasticity in a paloverde hybrid zone
Authors: FOX CHARLES , WADDELL KIM , DES LAURIES JAMES , MOUSSEAU TIMOTHY 
Published: December 2004

1. Although numerous studies have examined the ecology of plant resistance to herbivores and the distribution of herbivores within plant hybrid zones, few have examined how plant hybridization influences herbivore growth, development, or life history. The experiment reported here examines variation in survivorship, development time, and final adult body size of Stator limbatus reared on seeds of parental and hybrid Cercidium floridum‐×‐C. microphyllum trees from a paloverde hybrid zone in eastern California. Because S. limbatus exhibits egg size plasticity in response to host species, the size of eggs that females lay on hybrid and parental plants is also examined.2. The hypotheses (a) that seeds of hybrid trees are intermediate between those of the two parental species in their resistance to penetration by S. limbatus larvae; (b) that seeds of hybrid trees are intermediate in their suitability for the growth of larvae that successfully penetrate the seed‐coat; (c) that female S. limbatus can distinguish between hybrid trees and pure‐bred trees, as quantified by the size of eggs they lay on seeds of each taxon, and (d) that female S. limbatus can distinguish among individual hybrid trees, are tested.3. On average, S. limbatus survivorship was lower, development time longer, and emergence body mass lower on seeds of C. floridum than on seeds of C. microphyllum. Seeds of hybrid trees were, on average (across trees), intermediate between seeds of the parental species in the resistance of their seed‐coats to penetration by S. limbatus larvae and in their suitability for larval growth. Individual hybrid trees also varied in the resistance of their seeds to, and the suitability of their seeds for, S. limbatus larvae.4. Female S. limbatus laid significantly larger eggs on seeds of C. floridum than on seeds of C. microphyllum, and, on average, intermediate size eggs on hybrid trees. The size of eggs laid by females also varied among hybrid trees, with females laying C. floridum‐sized eggs on some trees, and C. microphyllum‐sized eggs on other trees. These results suggest that females have at least some ability to distinguish among hybrid trees, but there was no evidence that females laid larger eggs on poorer quality hybrid trees.
Oro‐cecal transit time: influence of a subsequent meal
Authors: Priebe M. G. , Wachters‐Hagedoorn R. E. , Stellaard F. , Heiner A. M. , Elzinga H. , Vonk R. J. 
Published: December 2004

AbstractBackground  Small intestinal and oro‐cecal transit time (OCTT) is determined for clinical diagnostics and research purposes. Experimental protocols used vary with respect to the inclusion of a subsequent meal during the test period. This study was conducted to elucidate whether the ingestion of a subsequent meal during the test period influences the OCTT of the test meal.Materials and methods  The OCTT of a liquid test meal, measured with the lactose‐[13C]ureide breath test, was compared between four groups of healthy volunteers (n = 36) who consumed the subsequent meal at different time points. Also, the OCTT was determined twice in eight subjects; a subsequent meal was ingested after 180 min (test A) and after 360 min (test B).Results  An apparently meal‐related increase in median OCTT was observed. The OCTT of the eight volunteers measured in test A (210; 210–349 median; quartiles) was significantly shorter than that found in test B (345; 300–375 min, P = 0·016). As result of the ingestion of the subsequent meal at 180 min the OCTT was shortened by 90; 64–116 min in 7/8 subjects.Conclusion  These data indicate that the ingestion of a subsequent meal affects the OCTT of a liquid test meal. This phenomenon could be explained by the increased intestinal motility in response to a meal, and should be taken into account when designing protocols for measurements of the OCTT and in the interpretation of small intestinal absorption studies.
A spatially explicit, individual‐based model to assess the role of estuarine nurseries in the early life history of North Sea herring,Clupea harengus
Authors: MAES JOACHIM , LIMBURG KARIN E. , VAN DE PUTTE ANTON , OLLEVIER FRANS 
Published: December 2004

AbstractHerring (Clupea harengus) enter and remain within North Sea estuaries during well‐defined periods of their early life history. The costs and benefits of the migrations between offshore spawning grounds and upper, low‐salinity zones of estuarine nurseries are identified using a dynamic state‐variable model, in which the fitness of an individual is maximized by selecting the most profitable habitat. Spatio‐temporal gradients in temperature, turbidity, food availability and predation risk simulate the environment. We modeled predation as a function of temperature, the optical properties of the ambient water, the time allocation of feeding and the abundance of whiting (Merlangius merlangus). Growth and metabolic costs were assessed using a bioenergetic model. Model runs using real input data for the Scheldt estuary (Belgium, The Netherlands) and the southern North Sea show that estuarine residence results in fitter individuals through a considerable increase in survival probability of age‐0 fish. Young herring pay for their migration into safer estuarine water by foregoing growth opportunities at sea. We suggest that temperature and, in particular, the time lag between estuarine and seawater temperatures, acts as a basic cue for herring to navigate in the heterogeneous space between the offshore spawning grounds at sea and the oligohaline nursery zone in estuaries.
Clupeoid larval growth and plankton production in the Benguela upwelling system
Authors: SKOGEN MORTEN D. 
Published: December 2004

AbstractUpwelling is a characteristic feature of the Benguela system. Strong upwelling leads to high primary production, which, in turn, supports large biomass of higher trophic levels. To analyse intra‐, interannual and decadal variability of fish recruitment, growth, and distribution, different methods to quantify this upwelling have been used. In the present work, an upwelling index, modelled diatom primary production, based on outputs from a numerical model for the Benguela upwelling system, is proposed. Upwelled water brings large amounts of nutrients into the euphotic zone and this supports primary productivity, which can be considered a preconditioner for the zooplankton that clupeoid larvae feed on. Therefore, it is assumed that high upwelling gives the potential for good feeding conditions for these larvae. This fact has motivated the use of the modelled index for upwelling intensity as a proxy for food availability and an investigation of the interannual variability of observed mean individual weight of Cape anchovy (Engraulis capensis) and sardine (Sardinops sagax) recruits. The study shows that the mean Cape anchovy recruit weight has a linear relationship with upwelling activity along the transport route (from the spawning to the nursery areas) and inside the nursery areas, while sardine have an Optimal Environmental Window (OEW) relationship to the upwelling on the transport route. A possible explanation for these observed differences is the prey the larvae feed on and the change in the plankton community as a function of upwelling activity.
Composition of fish communities in German lakes as related to lake morphology, trophic state, shore structure and human‐use intensity
Authors: Mehner Thomas , Diekmann Markus , Brämick Uwe , Lemcke Roland 
Published: December 2004

Summary1. Previous comparative analyses of fish communities in European lakes have mainly focused on the response of community composition to eutrophication. In addition, frequently only one or two lake habitats have been sampled.2. Here, we present fish community data from 67 lakes in north‐east Germany. Fish abundance was estimated in littoral, benthic and pelagic habitats from which a composite parameter indicating lake‐wide relative species abundances was derived. This parameter was used in group comparisons and non‐metric ordination procedures to explore, among 40 lake habitat descriptors sampled, those most important in structuring community composition.3. Fish community composition was mainly determined by maximum and mean depth, chlorophyll a content and lake volume. The impact of anthropogenic alterations of shore structure and human‐use intensity of lakes were of minor importance. The dominant fish species were vendace Coregonus albula, perch Perca fluviatilis, smelt Osmerus eperlanus and several cyprinids (roach Rutilus rutilus, bream Abramis brama, white bream Abramis bjoerkna and bleak Alburnus alburnus).4. A response of relative species abundance to lake productivity could be demonstrated for small perch, ruffe and bream. However, when the relationship between lake morphology and productivity was controlled for, differences in species abundances were not longer attributable to differences in productivity, but to maximum lake depth.5. This suggests that there are two distinct fish community types in Germany, namely the cold‐water community with vendace and perch inhabiting deeper lakes, and the warm‐water cyprinid community inhabiting more shallow lakes. The previously established conceptual model of a community succession from salmonids through perch to cyprinids with increasing eutrophication is hence not continous, but includes a switch between two lake and fish community types.
Comment on drag and reconfiguration of macrophytes
Authors: Sukhodolov Alexander 
Published: December 2004

Summary1. The experimental approach of Sand‐Jensen (2003), designed to examine quantitatively the response of freshwater macrophytes to physical forcing by moving water, is discussed. Specifically, it is emphasised that neglecting the principal difference between the wetted and the frontal area of the aquatic plants necessarily provides unacceptably large errors in estimates of drug coefficient.2. The empirical methodology employed in the study to generalise the data (Sand‐Jensen, 2003) suffers from a dimensional problem and can potentially lead to misleading conclusions. The methodology could be improved by using the relationship between dimensionless values of drag coefficient and dimensionless Reynolds number.
Plankton dynamics in a tropical floodplain lake: fish, nutrients, and the relative importance of bottom‐up and top‐down control
Authors: Rejas Danny , Declerck Steven , Auwerkerken Johan , Tak Paulus , Meester Luc De 
Published: December 2004

Summary1. Two enclosure experiments were carried out in Laguna Bufeos, a neotropical várzea lake located in the floodplain of River Ichilo (Bolivia). The experiments aimed (i) to assess the relative importance of bottom‐up and top‐down control on the plankton community, (ii) to assess the relative impact of direct and indirect effects of planktivorous fish on the zooplankton, and (iii) to attempt to identify the mechanisms responsible for these effects.2. During the first experiment, bottom‐up control seemed to dominate the planktonic food web. Compared with fishless enclosures, oxygen concentrations, chlorophyll a levels and the population densities of all cladoceran zooplankton taxa increased in enclosures with fish. Birth rates of Moina minuta, the dominant taxon, were substantially higher in the presence than in the absence of fish, whereas death rates did not differ between treatments. These results are the first to suggest that the positive effects of fish on crustacean zooplankton via effects on nutrient cycling and the enhancement of primary production can compensate for losses because of fish‐related mortality.3. During the second experiment, the direction of control appeared to vary between trophic levels: the phytoplankton appeared to be bottom‐up controlled whereas the zooplankton was mainly top‐down controlled. Chlorophyll a concentrations were enhanced by both fish and nutrient additions. The majority of the zooplankton taxa were reduced by the presence of fish. Birth rates of most cladoceran taxa did not differ between treatments, whereas death rates were higher in the enclosures with fish than in the fishless enclosures. Bosminopsis deitersi reached higher densities in the presence of fish, probably because of a release from predation by Chaoborus.4. We convincingly showed strong deviations from trophic cascade‐based expectations, supporting the idea that trophic cascades may be weak in tropical lakes.
Temporal stability of pond zooplankton assemblages
Authors: Steiner Christopher F. 
Published: December 2004

Summary1. A large body of recent theory has recently developed focused on the relationship between the species diversity of competitor assemblages and the temporal stability of total competitor biomass. Many of these models predict that stability can increase with increasing diversity.2. To explore natural relationships between zooplankton taxonomic diversity and temporal stability of total zooplankton biomass, 18 fishless, permanent ponds located in southern Michigan were surveyed over a 5 month period during a single growing season.3. Results showed that temporal variability in total zooplankton biomass (measured as the coefficient of variation or CV) decreased with increasing mean zooplankton taxonomic richness. Thus, temporal stability increased with increasing taxonomic richness, consistent with theoretical predictions.4. Decreases in the CV appeared to be because of portfolio effects (statistical averaging of species’ biomass fluctuations) rather than negative covariances among zooplankton taxa.5. The CV of zooplankton biomass was also related to several environmental variables, suggesting that taxonomic richness may not be the only mediator of biomass stability. The CV decreased with increasing relative abundance of grazer‐resistant algae (algae >35 μm in size) and the CV increased with increasing pond productivity.
The effect of support group on the mental health and quality of life for mothers with autistic children
Authors: Shu B.‐C. , Lung F.‐W. 
Published: December 2004

AbstractBackground  The purpose of this study was to explore the effect of support groups on the mental health and quality of life for mothers with autistic children.Method  A quasi‐experimental pre‐post control group design was used in this study. The mothers had children without chronic diseases diagnosed as autistic based on Diagnostic and Statistical Manual of Mental Disorder‐Fourth Edition (DSM‐IV) and were their primary caregivers. The mothers were assigned to control or intervention groups based on their willingness. The 10 weeks of the support group programme served as an intervention. There were three waves of data collection: pre‐test, post‐test, and after 1 month follow‐up. A total of 27 mothers with autistic children were assigned into experimental and control groups. In total, there were eight mothers in the experimental group and 19 mothers served as the control group.Results  The results of this study showed that mental health had not significantly improved in the intervention group compared to those in the control group at the end of the first month during follow‐up. However, the subjective well‐being and employment status had an effect on their mental health. Only the subjective well‐being had an effect on their quality of life.Conclusion  According to the results of this study, recommendations included (1) regularly promulgating a caregiver support group, (2) the advancement of training skills within the group, and (3) upgrading and promoting nurses’ ability to lead support groups in the future.